Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

29 files changed, 15900 insertions, 0 deletions

diff --git a/drivers/misc/mei/Kconfig b/drivers/misc/mei/Kconfig
new file mode 100644
index 000000000..f5fd5b786
--- /dev/null
+++ b/drivers/misc/mei/Kconfig
@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
+config INTEL_MEI
+	tristate "Intel Management Engine Interface"
+	depends on X86 && PCI
+	help
+	  The Intel Management Engine (Intel ME) provides Manageability,
+	  Security and Media services for system containing Intel chipsets.
+	  if selected /dev/mei misc device will be created.
+
+	  For more information see
+	  <https://software.intel.com/en-us/manageability/>
+
+config INTEL_MEI_ME
+	tristate "ME Enabled Intel Chipsets"
+	select INTEL_MEI
+	depends on X86 && PCI
+	help
+	  MEI support for ME Enabled Intel chipsets.
+
+	  Supported Chipsets are:
+	  7 Series Chipset Family
+	  6 Series Chipset Family
+	  5 Series Chipset Family
+	  4 Series Chipset Family
+	  Mobile 4 Series Chipset Family
+	  ICH9
+	  82946GZ/GL
+	  82G35 Express
+	  82Q963/Q965
+	  82P965/G965
+	  Mobile PM965/GM965
+	  Mobile GME965/GLE960
+	  82Q35 Express
+	  82G33/G31/P35/P31 Express
+	  82Q33 Express
+	  82X38/X48 Express
+
+config INTEL_MEI_TXE
+	tristate "Intel Trusted Execution Environment with ME Interface"
+	select INTEL_MEI
+	depends on X86 && PCI
+	help
+	  MEI Support for Trusted Execution Environment device on Intel SoCs
+
+	  Supported SoCs:
+	  Intel Bay Trail
+
+source "drivers/misc/mei/hdcp/Kconfig"
diff --git a/drivers/misc/mei/Makefile b/drivers/misc/mei/Makefile
new file mode 100644
index 000000000..f1c76f7ee
--- /dev/null
+++ b/drivers/misc/mei/Makefile
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) 2010-2019, Intel Corporation. All rights reserved.
+# Makefile - Intel Management Engine Interface (Intel MEI) Linux driver
+#
+obj-$(CONFIG_INTEL_MEI) += mei.o
+mei-objs := init.o
+mei-objs += hbm.o
+mei-objs += interrupt.o
+mei-objs += client.o
+mei-objs += main.o
+mei-objs += dma-ring.o
+mei-objs += bus.o
+mei-objs += bus-fixup.o
+mei-$(CONFIG_DEBUG_FS) += debugfs.o
+
+obj-$(CONFIG_INTEL_MEI_ME) += mei-me.o
+mei-me-objs := pci-me.o
+mei-me-objs += hw-me.o
+
+obj-$(CONFIG_INTEL_MEI_TXE) += mei-txe.o
+mei-txe-objs := pci-txe.o
+mei-txe-objs += hw-txe.o
+
+mei-$(CONFIG_EVENT_TRACING) += mei-trace.o
+CFLAGS_mei-trace.o = -I$(src)
+
+obj-$(CONFIG_INTEL_MEI_HDCP) += hdcp/
diff --git a/drivers/misc/mei/bus-fixup.c b/drivers/misc/mei/bus-fixup.c
new file mode 100644
index 000000000..c4c127558
--- /dev/null
+++ b/drivers/misc/mei/bus-fixup.c
@@ -0,0 +1,512 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2013-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+
+#include <linux/mei_cl_bus.h>
+
+#include "mei_dev.h"
+#include "client.h"
+
+#define MEI_UUID_NFC_INFO UUID_LE(0xd2de1625, 0x382d, 0x417d, \
+			0x48, 0xa4, 0xef, 0xab, 0xba, 0x8a, 0x12, 0x06)
+
+static const uuid_le mei_nfc_info_guid = MEI_UUID_NFC_INFO;
+
+#define MEI_UUID_NFC_HCI UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50, \
+			0x94, 0xd4, 0x50, 0x26, 0x67, 0x23, 0x77, 0x5c)
+
+#define MEI_UUID_WD UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, \
+			    0x89, 0x9D, 0xA9, 0x15, 0x14, 0xCB, 0x32, 0xAB)
+
+#define MEI_UUID_MKHIF_FIX UUID_LE(0x55213584, 0x9a29, 0x4916, \
+			0xba, 0xdf, 0xf, 0xb7, 0xed, 0x68, 0x2a, 0xeb)
+
+#define MEI_UUID_HDCP UUID_LE(0xB638AB7E, 0x94E2, 0x4EA2, \
+			      0xA5, 0x52, 0xD1, 0xC5, 0x4B, 0x62, 0x7F, 0x04)
+
+#define MEI_UUID_ANY NULL_UUID_LE
+
+/**
+ * number_of_connections - determine whether an client be on the bus
+ *    according number of connections
+ *    We support only clients:
+ *       1. with single connection
+ *       2. and fixed clients (max_number_of_connections == 0)
+ *
+ * @cldev: me clients device
+ */
+static void number_of_connections(struct mei_cl_device *cldev)
+{
+	if (cldev->me_cl->props.max_number_of_connections > 1)
+		cldev->do_match = 0;
+}
+
+/**
+ * blacklist - blacklist a client from the bus
+ *
+ * @cldev: me clients device
+ */
+static void blacklist(struct mei_cl_device *cldev)
+{
+	cldev->do_match = 0;
+}
+
+/**
+ * whitelist - forcefully whitelist client
+ *
+ * @cldev: me clients device
+ */
+static void whitelist(struct mei_cl_device *cldev)
+{
+	cldev->do_match = 1;
+}
+
+#define OSTYPE_LINUX    2
+struct mei_os_ver {
+	__le16 build;
+	__le16 reserved1;
+	u8  os_type;
+	u8  major;
+	u8  minor;
+	u8  reserved2;
+} __packed;
+
+#define MKHI_FEATURE_PTT 0x10
+
+struct mkhi_rule_id {
+	__le16 rule_type;
+	u8 feature_id;
+	u8 reserved;
+} __packed;
+
+struct mkhi_fwcaps {
+	struct mkhi_rule_id id;
+	u8 len;
+	u8 data[];
+} __packed;
+
+struct mkhi_fw_ver_block {
+	u16 minor;
+	u8 major;
+	u8 platform;
+	u16 buildno;
+	u16 hotfix;
+} __packed;
+
+struct mkhi_fw_ver {
+	struct mkhi_fw_ver_block ver[MEI_MAX_FW_VER_BLOCKS];
+} __packed;
+
+#define MKHI_FWCAPS_GROUP_ID 0x3
+#define MKHI_FWCAPS_SET_OS_VER_APP_RULE_CMD 6
+#define MKHI_GEN_GROUP_ID 0xFF
+#define MKHI_GEN_GET_FW_VERSION_CMD 0x2
+struct mkhi_msg_hdr {
+	u8  group_id;
+	u8  command;
+	u8  reserved;
+	u8  result;
+} __packed;
+
+struct mkhi_msg {
+	struct mkhi_msg_hdr hdr;
+	u8 data[];
+} __packed;
+
+#define MKHI_OSVER_BUF_LEN (sizeof(struct mkhi_msg_hdr) + \
+			    sizeof(struct mkhi_fwcaps) + \
+			    sizeof(struct mei_os_ver))
+static int mei_osver(struct mei_cl_device *cldev)
+{
+	const size_t size = MKHI_OSVER_BUF_LEN;
+	char buf[MKHI_OSVER_BUF_LEN];
+	struct mkhi_msg *req;
+	struct mkhi_fwcaps *fwcaps;
+	struct mei_os_ver *os_ver;
+	unsigned int mode = MEI_CL_IO_TX_BLOCKING | MEI_CL_IO_TX_INTERNAL;
+
+	memset(buf, 0, size);
+
+	req = (struct mkhi_msg *)buf;
+	req->hdr.group_id = MKHI_FWCAPS_GROUP_ID;
+	req->hdr.command = MKHI_FWCAPS_SET_OS_VER_APP_RULE_CMD;
+
+	fwcaps = (struct mkhi_fwcaps *)req->data;
+
+	fwcaps->id.rule_type = 0x0;
+	fwcaps->id.feature_id = MKHI_FEATURE_PTT;
+	fwcaps->len = sizeof(*os_ver);
+	os_ver = (struct mei_os_ver *)fwcaps->data;
+	os_ver->os_type = OSTYPE_LINUX;
+
+	return __mei_cl_send(cldev->cl, buf, size, mode);
+}
+
+#define MKHI_FWVER_BUF_LEN (sizeof(struct mkhi_msg_hdr) + \
+			    sizeof(struct mkhi_fw_ver))
+#define MKHI_FWVER_LEN(__num) (sizeof(struct mkhi_msg_hdr) + \
+			       sizeof(struct mkhi_fw_ver_block) * (__num))
+#define MKHI_RCV_TIMEOUT 500 /* receive timeout in msec */
+static int mei_fwver(struct mei_cl_device *cldev)
+{
+	char buf[MKHI_FWVER_BUF_LEN];
+	struct mkhi_msg req;
+	struct mkhi_msg *rsp;
+	struct mkhi_fw_ver *fwver;
+	int bytes_recv, ret, i;
+
+	memset(buf, 0, sizeof(buf));
+
+	req.hdr.group_id = MKHI_GEN_GROUP_ID;
+	req.hdr.command = MKHI_GEN_GET_FW_VERSION_CMD;
+
+	ret = __mei_cl_send(cldev->cl, (u8 *)&req, sizeof(req),
+			    MEI_CL_IO_TX_BLOCKING);
+	if (ret < 0) {
+		dev_err(&cldev->dev, "Could not send ReqFWVersion cmd ret = %d\n", ret);
+		return ret;
+	}
+
+	ret = 0;
+	bytes_recv = __mei_cl_recv(cldev->cl, buf, sizeof(buf), 0,
+				   MKHI_RCV_TIMEOUT);
+	if (bytes_recv < 0 || (size_t)bytes_recv < MKHI_FWVER_LEN(1)) {
+		/*
+		 * Should be at least one version block,
+		 * error out if nothing found
+		 */
+		dev_err(&cldev->dev, "Could not read FW version ret = %d\n", bytes_recv);
+		return -EIO;
+	}
+
+	rsp = (struct mkhi_msg *)buf;
+	fwver = (struct mkhi_fw_ver *)rsp->data;
+	memset(cldev->bus->fw_ver, 0, sizeof(cldev->bus->fw_ver));
+	for (i = 0; i < MEI_MAX_FW_VER_BLOCKS; i++) {
+		if ((size_t)bytes_recv < MKHI_FWVER_LEN(i + 1))
+			break;
+		dev_dbg(&cldev->dev, "FW version%d %d:%d.%d.%d.%d\n",
+			i, fwver->ver[i].platform,
+			fwver->ver[i].major, fwver->ver[i].minor,
+			fwver->ver[i].hotfix, fwver->ver[i].buildno);
+
+		cldev->bus->fw_ver[i].platform = fwver->ver[i].platform;
+		cldev->bus->fw_ver[i].major = fwver->ver[i].major;
+		cldev->bus->fw_ver[i].minor = fwver->ver[i].minor;
+		cldev->bus->fw_ver[i].hotfix = fwver->ver[i].hotfix;
+		cldev->bus->fw_ver[i].buildno = fwver->ver[i].buildno;
+	}
+
+	return ret;
+}
+
+static void mei_mkhi_fix(struct mei_cl_device *cldev)
+{
+	int ret;
+
+	/* No need to enable the client if nothing is needed from it */
+	if (!cldev->bus->fw_f_fw_ver_supported &&
+	    !cldev->bus->hbm_f_os_supported)
+		return;
+
+	ret = mei_cldev_enable(cldev);
+	if (ret)
+		return;
+
+	if (cldev->bus->fw_f_fw_ver_supported) {
+		ret = mei_fwver(cldev);
+		if (ret < 0)
+			dev_err(&cldev->dev, "FW version command failed %d\n",
+				ret);
+	}
+
+	if (cldev->bus->hbm_f_os_supported) {
+		ret = mei_osver(cldev);
+		if (ret < 0)
+			dev_err(&cldev->dev, "OS version command failed %d\n",
+				ret);
+	}
+	mei_cldev_disable(cldev);
+}
+
+/**
+ * mei_wd - wd client on the bus, change protocol version
+ *   as the API has changed.
+ *
+ * @cldev: me clients device
+ */
+#if IS_ENABLED(CONFIG_INTEL_MEI_ME)
+#include <linux/pci.h>
+#include "hw-me-regs.h"
+static void mei_wd(struct mei_cl_device *cldev)
+{
+	struct pci_dev *pdev = to_pci_dev(cldev->dev.parent);
+
+	if (pdev->device == MEI_DEV_ID_WPT_LP ||
+	    pdev->device == MEI_DEV_ID_SPT ||
+	    pdev->device == MEI_DEV_ID_SPT_H)
+		cldev->me_cl->props.protocol_version = 0x2;
+
+	cldev->do_match = 1;
+}
+#else
+static inline void mei_wd(struct mei_cl_device *cldev) {}
+#endif /* CONFIG_INTEL_MEI_ME */
+
+struct mei_nfc_cmd {
+	u8 command;
+	u8 status;
+	u16 req_id;
+	u32 reserved;
+	u16 data_size;
+	u8 sub_command;
+	u8 data[];
+} __packed;
+
+struct mei_nfc_reply {
+	u8 command;
+	u8 status;
+	u16 req_id;
+	u32 reserved;
+	u16 data_size;
+	u8 sub_command;
+	u8 reply_status;
+	u8 data[];
+} __packed;
+
+struct mei_nfc_if_version {
+	u8 radio_version_sw[3];
+	u8 reserved[3];
+	u8 radio_version_hw[3];
+	u8 i2c_addr;
+	u8 fw_ivn;
+	u8 vendor_id;
+	u8 radio_type;
+} __packed;
+
+
+#define MEI_NFC_CMD_MAINTENANCE 0x00
+#define MEI_NFC_SUBCMD_IF_VERSION 0x01
+
+/* Vendors */
+#define MEI_NFC_VENDOR_INSIDE 0x00
+#define MEI_NFC_VENDOR_NXP    0x01
+
+/* Radio types */
+#define MEI_NFC_VENDOR_INSIDE_UREAD 0x00
+#define MEI_NFC_VENDOR_NXP_PN544    0x01
+
+/**
+ * mei_nfc_if_version - get NFC interface version
+ *
+ * @cl: host client (nfc info)
+ * @ver: NFC interface version to be filled in
+ *
+ * Return: 0 on success; < 0 otherwise
+ */
+static int mei_nfc_if_version(struct mei_cl *cl,
+			      struct mei_nfc_if_version *ver)
+{
+	struct mei_device *bus;
+	struct mei_nfc_cmd cmd = {
+		.command = MEI_NFC_CMD_MAINTENANCE,
+		.data_size = 1,
+		.sub_command = MEI_NFC_SUBCMD_IF_VERSION,
+	};
+	struct mei_nfc_reply *reply = NULL;
+	size_t if_version_length;
+	int bytes_recv, ret;
+
+	bus = cl->dev;
+
+	WARN_ON(mutex_is_locked(&bus->device_lock));
+
+	ret = __mei_cl_send(cl, (u8 *)&cmd, sizeof(cmd), MEI_CL_IO_TX_BLOCKING);
+	if (ret < 0) {
+		dev_err(bus->dev, "Could not send IF version cmd ret = %d\n", ret);
+		return ret;
+	}
+
+	/* to be sure on the stack we alloc memory */
+	if_version_length = sizeof(*reply) + sizeof(*ver);
+
+	reply = kzalloc(if_version_length, GFP_KERNEL);
+	if (!reply)
+		return -ENOMEM;
+
+	ret = 0;
+	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length, 0, 0);
+	if (bytes_recv < 0 || (size_t)bytes_recv < if_version_length) {
+		dev_err(bus->dev, "Could not read IF version ret = %d\n", bytes_recv);
+		ret = -EIO;
+		goto err;
+	}
+
+	memcpy(ver, reply->data, sizeof(*ver));
+
+	dev_info(bus->dev, "NFC MEI VERSION: IVN 0x%x Vendor ID 0x%x Type 0x%x\n",
+		ver->fw_ivn, ver->vendor_id, ver->radio_type);
+
+err:
+	kfree(reply);
+	return ret;
+}
+
+/**
+ * mei_nfc_radio_name - derive nfc radio name from the interface version
+ *
+ * @ver: NFC radio version
+ *
+ * Return: radio name string
+ */
+static const char *mei_nfc_radio_name(struct mei_nfc_if_version *ver)
+{
+
+	if (ver->vendor_id == MEI_NFC_VENDOR_INSIDE) {
+		if (ver->radio_type == MEI_NFC_VENDOR_INSIDE_UREAD)
+			return "microread";
+	}
+
+	if (ver->vendor_id == MEI_NFC_VENDOR_NXP) {
+		if (ver->radio_type == MEI_NFC_VENDOR_NXP_PN544)
+			return "pn544";
+	}
+
+	return NULL;
+}
+
+/**
+ * mei_nfc - The nfc fixup function. The function retrieves nfc radio
+ *    name and set is as device attribute so we can load
+ *    the proper device driver for it
+ *
+ * @cldev: me client device (nfc)
+ */
+static void mei_nfc(struct mei_cl_device *cldev)
+{
+	struct mei_device *bus;
+	struct mei_cl *cl;
+	struct mei_me_client *me_cl = NULL;
+	struct mei_nfc_if_version ver;
+	const char *radio_name = NULL;
+	int ret;
+
+	bus = cldev->bus;
+
+	mutex_lock(&bus->device_lock);
+	/* we need to connect to INFO GUID */
+	cl = mei_cl_alloc_linked(bus);
+	if (IS_ERR(cl)) {
+		ret = PTR_ERR(cl);
+		cl = NULL;
+		dev_err(bus->dev, "nfc hook alloc failed %d\n", ret);
+		goto out;
+	}
+
+	me_cl = mei_me_cl_by_uuid(bus, &mei_nfc_info_guid);
+	if (!me_cl) {
+		ret = -ENOTTY;
+		dev_err(bus->dev, "Cannot find nfc info %d\n", ret);
+		goto out;
+	}
+
+	ret = mei_cl_connect(cl, me_cl, NULL);
+	if (ret < 0) {
+		dev_err(&cldev->dev, "Can't connect to the NFC INFO ME ret = %d\n",
+			ret);
+		goto out;
+	}
+
+	mutex_unlock(&bus->device_lock);
+
+	ret = mei_nfc_if_version(cl, &ver);
+	if (ret)
+		goto disconnect;
+
+	radio_name = mei_nfc_radio_name(&ver);
+
+	if (!radio_name) {
+		ret = -ENOENT;
+		dev_err(&cldev->dev, "Can't get the NFC interface version ret = %d\n",
+			ret);
+		goto disconnect;
+	}
+
+	dev_dbg(bus->dev, "nfc radio %s\n", radio_name);
+	strlcpy(cldev->name, radio_name, sizeof(cldev->name));
+
+disconnect:
+	mutex_lock(&bus->device_lock);
+	if (mei_cl_disconnect(cl) < 0)
+		dev_err(bus->dev, "Can't disconnect the NFC INFO ME\n");
+
+	mei_cl_flush_queues(cl, NULL);
+
+out:
+	mei_cl_unlink(cl);
+	mutex_unlock(&bus->device_lock);
+	mei_me_cl_put(me_cl);
+	kfree(cl);
+
+	if (ret)
+		cldev->do_match = 0;
+
+	dev_dbg(bus->dev, "end of fixup match = %d\n", cldev->do_match);
+}
+
+/**
+ * vt_support - enable on bus clients with vtag support
+ *
+ * @cldev: me clients device
+ */
+static void vt_support(struct mei_cl_device *cldev)
+{
+	if (cldev->me_cl->props.vt_supported == 1)
+		cldev->do_match = 1;
+}
+
+#define MEI_FIXUP(_uuid, _hook) { _uuid, _hook }
+
+static struct mei_fixup {
+
+	const uuid_le uuid;
+	void (*hook)(struct mei_cl_device *cldev);
+} mei_fixups[] = {
+	MEI_FIXUP(MEI_UUID_ANY, number_of_connections),
+	MEI_FIXUP(MEI_UUID_NFC_INFO, blacklist),
+	MEI_FIXUP(MEI_UUID_NFC_HCI, mei_nfc),
+	MEI_FIXUP(MEI_UUID_WD, mei_wd),
+	MEI_FIXUP(MEI_UUID_MKHIF_FIX, mei_mkhi_fix),
+	MEI_FIXUP(MEI_UUID_HDCP, whitelist),
+	MEI_FIXUP(MEI_UUID_ANY, vt_support),
+};
+
+/**
+ * mei_cldev_fixup - run fixup handlers
+ *
+ * @cldev: me client device
+ */
+void mei_cl_bus_dev_fixup(struct mei_cl_device *cldev)
+{
+	struct mei_fixup *f;
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(mei_fixups); i++) {
+
+		f = &mei_fixups[i];
+		if (uuid_le_cmp(f->uuid, MEI_UUID_ANY) == 0 ||
+		    uuid_le_cmp(f->uuid, *uuid) == 0)
+			f->hook(cldev);
+	}
+}
+
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
new file mode 100644
index 000000000..9cdaa7f3a
--- /dev/null
+++ b/drivers/misc/mei/bus.c
@@ -0,0 +1,1257 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2019, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/mei_cl_bus.h>
+
+#include "mei_dev.h"
+#include "client.h"
+
+#define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
+
+/**
+ * __mei_cl_send - internal client send (write)
+ *
+ * @cl: host client
+ * @buf: buffer to send
+ * @length: buffer length
+ * @mode: sending mode
+ *
+ * Return: written size bytes or < 0 on error
+ */
+ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+		      unsigned int mode)
+{
+	struct mei_device *bus;
+	struct mei_cl_cb *cb;
+	ssize_t rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	bus = cl->dev;
+
+	mutex_lock(&bus->device_lock);
+	if (bus->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	if (!mei_cl_is_connected(cl)) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	/* Check if we have an ME client device */
+	if (!mei_me_cl_is_active(cl->me_cl)) {
+		rets = -ENOTTY;
+		goto out;
+	}
+
+	if (length > mei_cl_mtu(cl)) {
+		rets = -EFBIG;
+		goto out;
+	}
+
+	while (cl->tx_cb_queued >= bus->tx_queue_limit) {
+		mutex_unlock(&bus->device_lock);
+		rets = wait_event_interruptible(cl->tx_wait,
+				cl->writing_state == MEI_WRITE_COMPLETE ||
+				(!mei_cl_is_connected(cl)));
+		mutex_lock(&bus->device_lock);
+		if (rets) {
+			if (signal_pending(current))
+				rets = -EINTR;
+			goto out;
+		}
+		if (!mei_cl_is_connected(cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+	}
+
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
+
+	cb->internal = !!(mode & MEI_CL_IO_TX_INTERNAL);
+	cb->blocking = !!(mode & MEI_CL_IO_TX_BLOCKING);
+	memcpy(cb->buf.data, buf, length);
+
+	rets = mei_cl_write(cl, cb);
+
+out:
+	mutex_unlock(&bus->device_lock);
+
+	return rets;
+}
+
+/**
+ * __mei_cl_recv - internal client receive (read)
+ *
+ * @cl: host client
+ * @buf: buffer to receive
+ * @length: buffer length
+ * @mode: io mode
+ * @timeout: recv timeout, 0 for infinite timeout
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
+		      unsigned int mode, unsigned long timeout)
+{
+	struct mei_device *bus;
+	struct mei_cl_cb *cb;
+	size_t r_length;
+	ssize_t rets;
+	bool nonblock = !!(mode & MEI_CL_IO_RX_NONBLOCK);
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	bus = cl->dev;
+
+	mutex_lock(&bus->device_lock);
+	if (bus->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	cb = mei_cl_read_cb(cl, NULL);
+	if (cb)
+		goto copy;
+
+	rets = mei_cl_read_start(cl, length, NULL);
+	if (rets && rets != -EBUSY)
+		goto out;
+
+	if (nonblock) {
+		rets = -EAGAIN;
+		goto out;
+	}
+
+	/* wait on event only if there is no other waiter */
+	/* synchronized under device mutex */
+	if (!waitqueue_active(&cl->rx_wait)) {
+
+		mutex_unlock(&bus->device_lock);
+
+		if (timeout) {
+			rets = wait_event_interruptible_timeout
+					(cl->rx_wait,
+					mei_cl_read_cb(cl, NULL) ||
+					(!mei_cl_is_connected(cl)),
+					msecs_to_jiffies(timeout));
+			if (rets == 0)
+				return -ETIME;
+			if (rets < 0) {
+				if (signal_pending(current))
+					return -EINTR;
+				return -ERESTARTSYS;
+			}
+		} else {
+			if (wait_event_interruptible
+					(cl->rx_wait,
+					mei_cl_read_cb(cl, NULL) ||
+					(!mei_cl_is_connected(cl)))) {
+				if (signal_pending(current))
+					return -EINTR;
+				return -ERESTARTSYS;
+			}
+		}
+
+		mutex_lock(&bus->device_lock);
+
+		if (!mei_cl_is_connected(cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+	}
+
+	cb = mei_cl_read_cb(cl, NULL);
+	if (!cb) {
+		rets = 0;
+		goto out;
+	}
+
+copy:
+	if (cb->status) {
+		rets = cb->status;
+		goto free;
+	}
+
+	r_length = min_t(size_t, length, cb->buf_idx);
+	memcpy(buf, cb->buf.data, r_length);
+	rets = r_length;
+
+free:
+	mei_cl_del_rd_completed(cl, cb);
+out:
+	mutex_unlock(&bus->device_lock);
+
+	return rets;
+}
+
+/**
+ * mei_cldev_send - me device send  (write)
+ *
+ * @cldev: me client device
+ * @buf: buffer to send
+ * @length: buffer length
+ *
+ * Return: written size in bytes or < 0 on error
+ */
+ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
+{
+	struct mei_cl *cl = cldev->cl;
+
+	return __mei_cl_send(cl, buf, length, MEI_CL_IO_TX_BLOCKING);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_send);
+
+/**
+ * mei_cldev_recv_nonblock - non block client receive (read)
+ *
+ * @cldev: me client device
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ *         -EAGAIN if function will block.
+ */
+ssize_t mei_cldev_recv_nonblock(struct mei_cl_device *cldev, u8 *buf,
+				size_t length)
+{
+	struct mei_cl *cl = cldev->cl;
+
+	return __mei_cl_recv(cl, buf, length, MEI_CL_IO_RX_NONBLOCK, 0);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_recv_nonblock);
+
+/**
+ * mei_cldev_recv - client receive (read)
+ *
+ * @cldev: me client device
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
+{
+	struct mei_cl *cl = cldev->cl;
+
+	return __mei_cl_recv(cl, buf, length, 0, 0);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_recv);
+
+/**
+ * mei_cl_bus_rx_work - dispatch rx event for a bus device
+ *
+ * @work: work
+ */
+static void mei_cl_bus_rx_work(struct work_struct *work)
+{
+	struct mei_cl_device *cldev;
+	struct mei_device *bus;
+
+	cldev = container_of(work, struct mei_cl_device, rx_work);
+
+	bus = cldev->bus;
+
+	if (cldev->rx_cb)
+		cldev->rx_cb(cldev);
+
+	mutex_lock(&bus->device_lock);
+	mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL);
+	mutex_unlock(&bus->device_lock);
+}
+
+/**
+ * mei_cl_bus_notif_work - dispatch FW notif event for a bus device
+ *
+ * @work: work
+ */
+static void mei_cl_bus_notif_work(struct work_struct *work)
+{
+	struct mei_cl_device *cldev;
+
+	cldev = container_of(work, struct mei_cl_device, notif_work);
+
+	if (cldev->notif_cb)
+		cldev->notif_cb(cldev);
+}
+
+/**
+ * mei_cl_bus_notify_event - schedule notify cb on bus client
+ *
+ * @cl: host client
+ *
+ * Return: true if event was scheduled
+ *         false if the client is not waiting for event
+ */
+bool mei_cl_bus_notify_event(struct mei_cl *cl)
+{
+	struct mei_cl_device *cldev = cl->cldev;
+
+	if (!cldev || !cldev->notif_cb)
+		return false;
+
+	if (!cl->notify_ev)
+		return false;
+
+	schedule_work(&cldev->notif_work);
+
+	cl->notify_ev = false;
+
+	return true;
+}
+
+/**
+ * mei_cl_bus_rx_event - schedule rx event
+ *
+ * @cl: host client
+ *
+ * Return: true if event was scheduled
+ *         false if the client is not waiting for event
+ */
+bool mei_cl_bus_rx_event(struct mei_cl *cl)
+{
+	struct mei_cl_device *cldev = cl->cldev;
+
+	if (!cldev || !cldev->rx_cb)
+		return false;
+
+	schedule_work(&cldev->rx_work);
+
+	return true;
+}
+
+/**
+ * mei_cldev_register_rx_cb - register Rx event callback
+ *
+ * @cldev: me client devices
+ * @rx_cb: callback function
+ *
+ * Return: 0 on success
+ *         -EALREADY if an callback is already registered
+ *         <0 on other errors
+ */
+int mei_cldev_register_rx_cb(struct mei_cl_device *cldev, mei_cldev_cb_t rx_cb)
+{
+	struct mei_device *bus = cldev->bus;
+	int ret;
+
+	if (!rx_cb)
+		return -EINVAL;
+	if (cldev->rx_cb)
+		return -EALREADY;
+
+	cldev->rx_cb = rx_cb;
+	INIT_WORK(&cldev->rx_work, mei_cl_bus_rx_work);
+
+	mutex_lock(&bus->device_lock);
+	ret = mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL);
+	mutex_unlock(&bus->device_lock);
+	if (ret && ret != -EBUSY)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_register_rx_cb);
+
+/**
+ * mei_cldev_register_notif_cb - register FW notification event callback
+ *
+ * @cldev: me client devices
+ * @notif_cb: callback function
+ *
+ * Return: 0 on success
+ *         -EALREADY if an callback is already registered
+ *         <0 on other errors
+ */
+int mei_cldev_register_notif_cb(struct mei_cl_device *cldev,
+				mei_cldev_cb_t notif_cb)
+{
+	struct mei_device *bus = cldev->bus;
+	int ret;
+
+	if (!notif_cb)
+		return -EINVAL;
+
+	if (cldev->notif_cb)
+		return -EALREADY;
+
+	cldev->notif_cb = notif_cb;
+	INIT_WORK(&cldev->notif_work, mei_cl_bus_notif_work);
+
+	mutex_lock(&bus->device_lock);
+	ret = mei_cl_notify_request(cldev->cl, NULL, 1);
+	mutex_unlock(&bus->device_lock);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_register_notif_cb);
+
+/**
+ * mei_cldev_get_drvdata - driver data getter
+ *
+ * @cldev: mei client device
+ *
+ * Return: driver private data
+ */
+void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev)
+{
+	return dev_get_drvdata(&cldev->dev);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata);
+
+/**
+ * mei_cldev_set_drvdata - driver data setter
+ *
+ * @cldev: mei client device
+ * @data: data to store
+ */
+void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data)
+{
+	dev_set_drvdata(&cldev->dev, data);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata);
+
+/**
+ * mei_cldev_uuid - return uuid of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client uuid
+ */
+const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev)
+{
+	return mei_me_cl_uuid(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_uuid);
+
+/**
+ * mei_cldev_ver - return protocol version of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client protocol version
+ */
+u8 mei_cldev_ver(const struct mei_cl_device *cldev)
+{
+	return mei_me_cl_ver(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_ver);
+
+/**
+ * mei_cldev_enabled - check whether the device is enabled
+ *
+ * @cldev: mei client device
+ *
+ * Return: true if me client is initialized and connected
+ */
+bool mei_cldev_enabled(struct mei_cl_device *cldev)
+{
+	return mei_cl_is_connected(cldev->cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_enabled);
+
+/**
+ * mei_cl_bus_module_get - acquire module of the underlying
+ *    hw driver.
+ *
+ * @cldev: mei client device
+ *
+ * Return: true on success; false if the module was removed.
+ */
+static bool mei_cl_bus_module_get(struct mei_cl_device *cldev)
+{
+	return try_module_get(cldev->bus->dev->driver->owner);
+}
+
+/**
+ * mei_cl_bus_module_put -  release the underlying hw module.
+ *
+ * @cldev: mei client device
+ */
+static void mei_cl_bus_module_put(struct mei_cl_device *cldev)
+{
+	module_put(cldev->bus->dev->driver->owner);
+}
+
+/**
+ * mei_cl_bus_vtag - get bus vtag entry wrapper
+ *     The tag for bus client is always first.
+ *
+ * @cl: host client
+ *
+ * Return: bus vtag or NULL
+ */
+static inline struct mei_cl_vtag *mei_cl_bus_vtag(struct mei_cl *cl)
+{
+	return list_first_entry_or_null(&cl->vtag_map,
+					struct mei_cl_vtag, list);
+}
+
+/**
+ * mei_cl_bus_vtag_alloc - add bus client entry to vtag map
+ *
+ * @cldev: me client device
+ *
+ * Return:
+ * * 0 on success
+ * * -ENOMEM if memory allocation failed
+ */
+static int mei_cl_bus_vtag_alloc(struct mei_cl_device *cldev)
+{
+	struct mei_cl *cl = cldev->cl;
+	struct mei_cl_vtag *cl_vtag;
+
+	/*
+	 * Bail out if the client does not supports vtags
+	 * or has already allocated one
+	 */
+	if (mei_cl_vt_support_check(cl) || mei_cl_bus_vtag(cl))
+		return 0;
+
+	cl_vtag = mei_cl_vtag_alloc(NULL, 0);
+	if (IS_ERR(cl_vtag))
+		return -ENOMEM;
+
+	list_add_tail(&cl_vtag->list, &cl->vtag_map);
+
+	return 0;
+}
+
+/**
+ * mei_cl_bus_vtag_free - remove the bus entry from vtag map
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_vtag_free(struct mei_cl_device *cldev)
+{
+	struct mei_cl *cl = cldev->cl;
+	struct mei_cl_vtag *cl_vtag;
+
+	cl_vtag = mei_cl_bus_vtag(cl);
+	if (!cl_vtag)
+		return;
+
+	list_del(&cl_vtag->list);
+	kfree(cl_vtag);
+}
+
+/**
+ * mei_cldev_enable - enable me client device
+ *     create connection with me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_enable(struct mei_cl_device *cldev)
+{
+	struct mei_device *bus = cldev->bus;
+	struct mei_cl *cl;
+	int ret;
+
+	cl = cldev->cl;
+
+	mutex_lock(&bus->device_lock);
+	if (cl->state == MEI_FILE_UNINITIALIZED) {
+		ret = mei_cl_link(cl);
+		if (ret)
+			goto out;
+		/* update pointers */
+		cl->cldev = cldev;
+	}
+
+	if (mei_cl_is_connected(cl)) {
+		ret = 0;
+		goto out;
+	}
+
+	if (!mei_me_cl_is_active(cldev->me_cl)) {
+		dev_err(&cldev->dev, "me client is not active\n");
+		ret = -ENOTTY;
+		goto out;
+	}
+
+	ret = mei_cl_bus_vtag_alloc(cldev);
+	if (ret)
+		goto out;
+
+	ret = mei_cl_connect(cl, cldev->me_cl, NULL);
+	if (ret < 0) {
+		dev_err(&cldev->dev, "cannot connect\n");
+		mei_cl_bus_vtag_free(cldev);
+	}
+
+out:
+	mutex_unlock(&bus->device_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_enable);
+
+/**
+ * mei_cldev_unregister_callbacks - internal wrapper for unregistering
+ *  callbacks.
+ *
+ * @cldev: client device
+ */
+static void mei_cldev_unregister_callbacks(struct mei_cl_device *cldev)
+{
+	if (cldev->rx_cb) {
+		cancel_work_sync(&cldev->rx_work);
+		cldev->rx_cb = NULL;
+	}
+
+	if (cldev->notif_cb) {
+		cancel_work_sync(&cldev->notif_work);
+		cldev->notif_cb = NULL;
+	}
+}
+
+/**
+ * mei_cldev_disable - disable me client device
+ *     disconnect form the me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_disable(struct mei_cl_device *cldev)
+{
+	struct mei_device *bus;
+	struct mei_cl *cl;
+	int err;
+
+	if (!cldev)
+		return -ENODEV;
+
+	cl = cldev->cl;
+
+	bus = cldev->bus;
+
+	mei_cldev_unregister_callbacks(cldev);
+
+	mutex_lock(&bus->device_lock);
+
+	mei_cl_bus_vtag_free(cldev);
+
+	if (!mei_cl_is_connected(cl)) {
+		dev_dbg(bus->dev, "Already disconnected\n");
+		err = 0;
+		goto out;
+	}
+
+	err = mei_cl_disconnect(cl);
+	if (err < 0)
+		dev_err(bus->dev, "Could not disconnect from the ME client\n");
+
+out:
+	/* Flush queues and remove any pending read */
+	mei_cl_flush_queues(cl, NULL);
+	mei_cl_unlink(cl);
+
+	mutex_unlock(&bus->device_lock);
+	return err;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_disable);
+
+/**
+ * mei_cl_device_find - find matching entry in the driver id table
+ *
+ * @cldev: me client device
+ * @cldrv: me client driver
+ *
+ * Return: id on success; NULL if no id is matching
+ */
+static const
+struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev,
+					    struct mei_cl_driver *cldrv)
+{
+	const struct mei_cl_device_id *id;
+	const uuid_le *uuid;
+	u8 version;
+	bool match;
+
+	uuid = mei_me_cl_uuid(cldev->me_cl);
+	version = mei_me_cl_ver(cldev->me_cl);
+
+	id = cldrv->id_table;
+	while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) {
+		if (!uuid_le_cmp(*uuid, id->uuid)) {
+			match = true;
+
+			if (cldev->name[0])
+				if (strncmp(cldev->name, id->name,
+					    sizeof(id->name)))
+					match = false;
+
+			if (id->version != MEI_CL_VERSION_ANY)
+				if (id->version != version)
+					match = false;
+			if (match)
+				return id;
+		}
+
+		id++;
+	}
+
+	return NULL;
+}
+
+/**
+ * mei_cl_device_match  - device match function
+ *
+ * @dev: device
+ * @drv: driver
+ *
+ * Return:  1 if matching device was found 0 otherwise
+ */
+static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct mei_cl_driver *cldrv = to_mei_cl_driver(drv);
+	const struct mei_cl_device_id *found_id;
+
+	if (!cldev)
+		return 0;
+
+	if (!cldev->do_match)
+		return 0;
+
+	if (!cldrv || !cldrv->id_table)
+		return 0;
+
+	found_id = mei_cl_device_find(cldev, cldrv);
+	if (found_id)
+		return 1;
+
+	return 0;
+}
+
+/**
+ * mei_cl_device_probe - bus probe function
+ *
+ * @dev: device
+ *
+ * Return:  0 on success; < 0 otherwise
+ */
+static int mei_cl_device_probe(struct device *dev)
+{
+	struct mei_cl_device *cldev;
+	struct mei_cl_driver *cldrv;
+	const struct mei_cl_device_id *id;
+	int ret;
+
+	cldev = to_mei_cl_device(dev);
+	cldrv = to_mei_cl_driver(dev->driver);
+
+	if (!cldev)
+		return 0;
+
+	if (!cldrv || !cldrv->probe)
+		return -ENODEV;
+
+	id = mei_cl_device_find(cldev, cldrv);
+	if (!id)
+		return -ENODEV;
+
+	if (!mei_cl_bus_module_get(cldev)) {
+		dev_err(&cldev->dev, "get hw module failed");
+		return -ENODEV;
+	}
+
+	ret = cldrv->probe(cldev, id);
+	if (ret) {
+		mei_cl_bus_module_put(cldev);
+		return ret;
+	}
+
+	__module_get(THIS_MODULE);
+	return 0;
+}
+
+/**
+ * mei_cl_device_remove - remove device from the bus
+ *
+ * @dev: device
+ *
+ * Return:  0 on success; < 0 otherwise
+ */
+static int mei_cl_device_remove(struct device *dev)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct mei_cl_driver *cldrv;
+	int ret = 0;
+
+	if (!cldev || !dev->driver)
+		return 0;
+
+	cldrv = to_mei_cl_driver(dev->driver);
+	if (cldrv->remove)
+		ret = cldrv->remove(cldev);
+
+	mei_cldev_unregister_callbacks(cldev);
+
+	mei_cl_bus_module_put(cldev);
+	module_put(THIS_MODULE);
+
+	return ret;
+}
+
+static ssize_t name_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s", cldev->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t uuid_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+
+	return sprintf(buf, "%pUl", uuid);
+}
+static DEVICE_ATTR_RO(uuid);
+
+static ssize_t version_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	u8 version = mei_me_cl_ver(cldev->me_cl);
+
+	return sprintf(buf, "%02X", version);
+}
+static DEVICE_ATTR_RO(version);
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	u8 version = mei_me_cl_ver(cldev->me_cl);
+
+	return scnprintf(buf, PAGE_SIZE, "mei:%s:%pUl:%02X:",
+			 cldev->name, uuid, version);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t max_conn_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	u8 maxconn = mei_me_cl_max_conn(cldev->me_cl);
+
+	return sprintf(buf, "%d", maxconn);
+}
+static DEVICE_ATTR_RO(max_conn);
+
+static ssize_t fixed_show(struct device *dev, struct device_attribute *a,
+			  char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	u8 fixed = mei_me_cl_fixed(cldev->me_cl);
+
+	return sprintf(buf, "%d", fixed);
+}
+static DEVICE_ATTR_RO(fixed);
+
+static ssize_t vtag_show(struct device *dev, struct device_attribute *a,
+			 char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	bool vt = mei_me_cl_vt(cldev->me_cl);
+
+	return sprintf(buf, "%d", vt);
+}
+static DEVICE_ATTR_RO(vtag);
+
+static ssize_t max_len_show(struct device *dev, struct device_attribute *a,
+			    char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	u32 maxlen = mei_me_cl_max_len(cldev->me_cl);
+
+	return sprintf(buf, "%u", maxlen);
+}
+static DEVICE_ATTR_RO(max_len);
+
+static struct attribute *mei_cldev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_uuid.attr,
+	&dev_attr_version.attr,
+	&dev_attr_modalias.attr,
+	&dev_attr_max_conn.attr,
+	&dev_attr_fixed.attr,
+	&dev_attr_vtag.attr,
+	&dev_attr_max_len.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(mei_cldev);
+
+/**
+ * mei_cl_device_uevent - me client bus uevent handler
+ *
+ * @dev: device
+ * @env: uevent kobject
+ *
+ * Return: 0 on success -ENOMEM on when add_uevent_var fails
+ */
+static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	u8 version = mei_me_cl_ver(cldev->me_cl);
+
+	if (add_uevent_var(env, "MEI_CL_VERSION=%d", version))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:",
+			   cldev->name, uuid, version))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static struct bus_type mei_cl_bus_type = {
+	.name		= "mei",
+	.dev_groups	= mei_cldev_groups,
+	.match		= mei_cl_device_match,
+	.probe		= mei_cl_device_probe,
+	.remove		= mei_cl_device_remove,
+	.uevent		= mei_cl_device_uevent,
+};
+
+static struct mei_device *mei_dev_bus_get(struct mei_device *bus)
+{
+	if (bus)
+		get_device(bus->dev);
+
+	return bus;
+}
+
+static void mei_dev_bus_put(struct mei_device *bus)
+{
+	if (bus)
+		put_device(bus->dev);
+}
+
+static void mei_cl_bus_dev_release(struct device *dev)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+
+	if (!cldev)
+		return;
+
+	mei_me_cl_put(cldev->me_cl);
+	mei_dev_bus_put(cldev->bus);
+	mei_cl_unlink(cldev->cl);
+	kfree(cldev->cl);
+	kfree(cldev);
+}
+
+static const struct device_type mei_cl_device_type = {
+	.release = mei_cl_bus_dev_release,
+};
+
+/**
+ * mei_cl_bus_set_name - set device name for me client device
+ *  <controller>-<client device>
+ *  Example: 0000:00:16.0-55213584-9a29-4916-badf-0fb7ed682aeb
+ *
+ * @cldev: me client device
+ */
+static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev)
+{
+	dev_set_name(&cldev->dev, "%s-%pUl",
+		     dev_name(cldev->bus->dev),
+		     mei_me_cl_uuid(cldev->me_cl));
+}
+
+/**
+ * mei_cl_bus_dev_alloc - initialize and allocate mei client device
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Return: allocated device structur or NULL on allocation failure
+ */
+static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus,
+						  struct mei_me_client *me_cl)
+{
+	struct mei_cl_device *cldev;
+	struct mei_cl *cl;
+
+	cldev = kzalloc(sizeof(*cldev), GFP_KERNEL);
+	if (!cldev)
+		return NULL;
+
+	cl = mei_cl_allocate(bus);
+	if (!cl) {
+		kfree(cldev);
+		return NULL;
+	}
+
+	device_initialize(&cldev->dev);
+	cldev->dev.parent = bus->dev;
+	cldev->dev.bus    = &mei_cl_bus_type;
+	cldev->dev.type   = &mei_cl_device_type;
+	cldev->bus        = mei_dev_bus_get(bus);
+	cldev->me_cl      = mei_me_cl_get(me_cl);
+	cldev->cl         = cl;
+	mei_cl_bus_set_name(cldev);
+	cldev->is_added   = 0;
+	INIT_LIST_HEAD(&cldev->bus_list);
+
+	return cldev;
+}
+
+/**
+ * mei_cl_dev_setup - setup me client device
+ *    run fix up routines and set the device name
+ *
+ * @bus: mei device
+ * @cldev: me client device
+ *
+ * Return: true if the device is eligible for enumeration
+ */
+static bool mei_cl_bus_dev_setup(struct mei_device *bus,
+				 struct mei_cl_device *cldev)
+{
+	cldev->do_match = 1;
+	mei_cl_bus_dev_fixup(cldev);
+
+	/* the device name can change during fix up */
+	if (cldev->do_match)
+		mei_cl_bus_set_name(cldev);
+
+	return cldev->do_match == 1;
+}
+
+/**
+ * mei_cl_bus_dev_add - add me client devices
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success; < 0 on failre
+ */
+static int mei_cl_bus_dev_add(struct mei_cl_device *cldev)
+{
+	int ret;
+
+	dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n",
+		mei_me_cl_uuid(cldev->me_cl),
+		mei_me_cl_ver(cldev->me_cl));
+	ret = device_add(&cldev->dev);
+	if (!ret)
+		cldev->is_added = 1;
+
+	return ret;
+}
+
+/**
+ * mei_cl_bus_dev_stop - stop the driver
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev)
+{
+	if (cldev->is_added)
+		device_release_driver(&cldev->dev);
+}
+
+/**
+ * mei_cl_bus_dev_destroy - destroy me client devices object
+ *
+ * @cldev: me client device
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev)
+{
+
+	WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock));
+
+	if (!cldev->is_added)
+		return;
+
+	device_del(&cldev->dev);
+
+	list_del_init(&cldev->bus_list);
+
+	cldev->is_added = 0;
+	put_device(&cldev->dev);
+}
+
+/**
+ * mei_cl_bus_remove_device - remove a devices form the bus
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_remove_device(struct mei_cl_device *cldev)
+{
+	mei_cl_bus_dev_stop(cldev);
+	mei_cl_bus_dev_destroy(cldev);
+}
+
+/**
+ * mei_cl_bus_remove_devices - remove all devices form the bus
+ *
+ * @bus: mei device
+ */
+void mei_cl_bus_remove_devices(struct mei_device *bus)
+{
+	struct mei_cl_device *cldev, *next;
+
+	mutex_lock(&bus->cl_bus_lock);
+	list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list)
+		mei_cl_bus_remove_device(cldev);
+	mutex_unlock(&bus->cl_bus_lock);
+}
+
+
+/**
+ * mei_cl_bus_dev_init - allocate and initializes an mei client devices
+ *     based on me client
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_init(struct mei_device *bus,
+				struct mei_me_client *me_cl)
+{
+	struct mei_cl_device *cldev;
+
+	WARN_ON(!mutex_is_locked(&bus->cl_bus_lock));
+
+	dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl));
+
+	if (me_cl->bus_added)
+		return;
+
+	cldev = mei_cl_bus_dev_alloc(bus, me_cl);
+	if (!cldev)
+		return;
+
+	me_cl->bus_added = true;
+	list_add_tail(&cldev->bus_list, &bus->device_list);
+
+}
+
+/**
+ * mei_cl_bus_rescan - scan me clients list and add create
+ *    devices for eligible clients
+ *
+ * @bus: mei device
+ */
+static void mei_cl_bus_rescan(struct mei_device *bus)
+{
+	struct mei_cl_device *cldev, *n;
+	struct mei_me_client *me_cl;
+
+	mutex_lock(&bus->cl_bus_lock);
+
+	down_read(&bus->me_clients_rwsem);
+	list_for_each_entry(me_cl, &bus->me_clients, list)
+		mei_cl_bus_dev_init(bus, me_cl);
+	up_read(&bus->me_clients_rwsem);
+
+	list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) {
+
+		if (!mei_me_cl_is_active(cldev->me_cl)) {
+			mei_cl_bus_remove_device(cldev);
+			continue;
+		}
+
+		if (cldev->is_added)
+			continue;
+
+		if (mei_cl_bus_dev_setup(bus, cldev))
+			mei_cl_bus_dev_add(cldev);
+		else {
+			list_del_init(&cldev->bus_list);
+			put_device(&cldev->dev);
+		}
+	}
+	mutex_unlock(&bus->cl_bus_lock);
+
+	dev_dbg(bus->dev, "rescan end");
+}
+
+void mei_cl_bus_rescan_work(struct work_struct *work)
+{
+	struct mei_device *bus =
+		container_of(work, struct mei_device, bus_rescan_work);
+
+	mei_cl_bus_rescan(bus);
+}
+
+int __mei_cldev_driver_register(struct mei_cl_driver *cldrv,
+				struct module *owner)
+{
+	int err;
+
+	cldrv->driver.name = cldrv->name;
+	cldrv->driver.owner = owner;
+	cldrv->driver.bus = &mei_cl_bus_type;
+
+	err = driver_register(&cldrv->driver);
+	if (err)
+		return err;
+
+	pr_debug("mei: driver [%s] registered\n", cldrv->driver.name);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__mei_cldev_driver_register);
+
+void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv)
+{
+	driver_unregister(&cldrv->driver);
+
+	pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister);
+
+
+int __init mei_cl_bus_init(void)
+{
+	return bus_register(&mei_cl_bus_type);
+}
+
+void __exit mei_cl_bus_exit(void)
+{
+	bus_unregister(&mei_cl_bus_type);
+}
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
new file mode 100644
index 000000000..aa87542f1
--- /dev/null
+++ b/drivers/misc/mei/client.c
@@ -0,0 +1,2139 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/sched/signal.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+/**
+ * mei_me_cl_init - initialize me client
+ *
+ * @me_cl: me client
+ */
+void mei_me_cl_init(struct mei_me_client *me_cl)
+{
+	INIT_LIST_HEAD(&me_cl->list);
+	kref_init(&me_cl->refcnt);
+}
+
+/**
+ * mei_me_cl_get - increases me client refcount
+ *
+ * @me_cl: me client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: me client or NULL
+ */
+struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
+{
+	if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
+		return me_cl;
+
+	return NULL;
+}
+
+/**
+ * mei_me_cl_release - free me client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @ref: me_client refcount
+ */
+static void mei_me_cl_release(struct kref *ref)
+{
+	struct mei_me_client *me_cl =
+		container_of(ref, struct mei_me_client, refcnt);
+
+	kfree(me_cl);
+}
+
+/**
+ * mei_me_cl_put - decrease me client refcount and free client if necessary
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @me_cl: me client
+ */
+void mei_me_cl_put(struct mei_me_client *me_cl)
+{
+	if (me_cl)
+		kref_put(&me_cl->refcnt, mei_me_cl_release);
+}
+
+/**
+ * __mei_me_cl_del  - delete me client from the list and decrease
+ *     reference counter
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+	if (!me_cl)
+		return;
+
+	list_del_init(&me_cl->list);
+	mei_me_cl_put(me_cl);
+}
+
+/**
+ * mei_me_cl_del - delete me client from the list and decrease
+ *     reference counter
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ */
+void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+	down_write(&dev->me_clients_rwsem);
+	__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_me_cl_add - add me client to the list
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ */
+void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+	down_write(&dev->me_clients_rwsem);
+	list_add(&me_cl->list, &dev->me_clients);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * __mei_me_cl_by_uuid - locate me client by uuid
+ *	increases ref count
+ *
+ * @dev: mei device
+ * @uuid: me client uuid
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *pn;
+
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0)
+			return mei_me_cl_get(me_cl);
+	}
+
+	return NULL;
+}
+
+/**
+ * mei_me_cl_by_uuid - locate me client by uuid
+ *	increases ref count
+ *
+ * @dev: mei device
+ * @uuid: me client uuid
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * mei_me_cl_by_id - locate me client by client id
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @client_id: me client id
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
+{
+
+	struct mei_me_client *__me_cl, *me_cl = NULL;
+
+	down_read(&dev->me_clients_rwsem);
+	list_for_each_entry(__me_cl, &dev->me_clients, list) {
+		if (__me_cl->client_id == client_id) {
+			me_cl = mei_me_cl_get(__me_cl);
+			break;
+		}
+	}
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @client_id: me client id
+ *
+ * Return: me client or null if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *pn;
+
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0 &&
+		    me_cl->client_id == client_id)
+			return mei_me_cl_get(me_cl);
+	}
+
+	return NULL;
+}
+
+
+/**
+ * mei_me_cl_by_uuid_id - locate me client by client id and uuid
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @client_id: me client id
+ *
+ * Return: me client or null if not found
+ */
+struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id)
+{
+	struct mei_me_client *me_cl;
+
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * mei_me_cl_rm_by_uuid - remove all me clients matching uuid
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+
+	dev_dbg(dev->dev, "remove %pUl\n", uuid);
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	__mei_me_cl_del(dev, me_cl);
+	mei_me_cl_put(me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @id: me client id
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
+{
+	struct mei_me_client *me_cl;
+
+	dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
+	__mei_me_cl_del(dev, me_cl);
+	mei_me_cl_put(me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_me_cl_rm_all - remove all me clients
+ *
+ * @dev: the device structure
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_all(struct mei_device *dev)
+{
+	struct mei_me_client *me_cl, *next;
+
+	down_write(&dev->me_clients_rwsem);
+	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
+		__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_io_cb_free - free mei_cb_private related memory
+ *
+ * @cb: mei callback struct
+ */
+void mei_io_cb_free(struct mei_cl_cb *cb)
+{
+	if (cb == NULL)
+		return;
+
+	list_del(&cb->list);
+	kfree(cb->buf.data);
+	kfree(cb);
+}
+
+/**
+ * mei_tx_cb_queue - queue tx callback
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cb: mei callback struct
+ * @head: an instance of list to queue on
+ */
+static inline void mei_tx_cb_enqueue(struct mei_cl_cb *cb,
+				     struct list_head *head)
+{
+	list_add_tail(&cb->list, head);
+	cb->cl->tx_cb_queued++;
+}
+
+/**
+ * mei_tx_cb_dequeue - dequeue tx callback
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cb: mei callback struct to dequeue and free
+ */
+static inline void mei_tx_cb_dequeue(struct mei_cl_cb *cb)
+{
+	if (!WARN_ON(cb->cl->tx_cb_queued == 0))
+		cb->cl->tx_cb_queued--;
+
+	mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_set_read_by_fp - set pending_read flag to vtag struct for given fp
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cl: mei client
+ * @fp: pointer to file structure
+ */
+static void mei_cl_set_read_by_fp(const struct mei_cl *cl,
+				  const struct file *fp)
+{
+	struct mei_cl_vtag *cl_vtag;
+
+	list_for_each_entry(cl_vtag, &cl->vtag_map, list) {
+		if (cl_vtag->fp == fp) {
+			cl_vtag->pending_read = true;
+			return;
+		}
+	}
+}
+
+/**
+ * mei_io_cb_init - allocate and initialize io callback
+ *
+ * @cl: mei client
+ * @type: operation type
+ * @fp: pointer to file structure
+ *
+ * Return: mei_cl_cb pointer or NULL;
+ */
+static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
+					enum mei_cb_file_ops type,
+					const struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	cb = kzalloc(sizeof(*cb), GFP_KERNEL);
+	if (!cb)
+		return NULL;
+
+	INIT_LIST_HEAD(&cb->list);
+	cb->fp = fp;
+	cb->cl = cl;
+	cb->buf_idx = 0;
+	cb->fop_type = type;
+	cb->vtag = 0;
+
+	return cb;
+}
+
+/**
+ * mei_io_list_flush_cl - removes cbs belonging to the cl.
+ *
+ * @head:  an instance of our list structure
+ * @cl:    host client
+ */
+static void mei_io_list_flush_cl(struct list_head *head,
+				 const struct mei_cl *cl)
+{
+	struct mei_cl_cb *cb, *next;
+
+	list_for_each_entry_safe(cb, next, head, list) {
+		if (cl == cb->cl) {
+			list_del_init(&cb->list);
+			if (cb->fop_type == MEI_FOP_READ)
+				mei_io_cb_free(cb);
+		}
+	}
+}
+
+/**
+ * mei_io_tx_list_free_cl - removes cb belonging to the cl and free them
+ *
+ * @head: An instance of our list structure
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ */
+static void mei_io_tx_list_free_cl(struct list_head *head,
+				   const struct mei_cl *cl,
+				   const struct file *fp)
+{
+	struct mei_cl_cb *cb, *next;
+
+	list_for_each_entry_safe(cb, next, head, list) {
+		if (cl == cb->cl && (!fp || fp == cb->fp))
+			mei_tx_cb_dequeue(cb);
+	}
+}
+
+/**
+ * mei_io_list_free_fp - free cb from a list that matches file pointer
+ *
+ * @head: io list
+ * @fp: file pointer (matching cb file object), may be NULL
+ */
+static void mei_io_list_free_fp(struct list_head *head, const struct file *fp)
+{
+	struct mei_cl_cb *cb, *next;
+
+	list_for_each_entry_safe(cb, next, head, list)
+		if (!fp || fp == cb->fp)
+			mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_free_pending - free pending cb
+ *
+ * @cl: host client
+ */
+static void mei_cl_free_pending(struct mei_cl *cl)
+{
+	struct mei_cl_cb *cb;
+
+	cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
+	mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
+ *
+ * @cl: host client
+ * @length: size of the buffer
+ * @fop_type: operation type
+ * @fp: associated file pointer (might be NULL)
+ *
+ * Return: cb on success and NULL on failure
+ */
+struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
+				  enum mei_cb_file_ops fop_type,
+				  const struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	cb = mei_io_cb_init(cl, fop_type, fp);
+	if (!cb)
+		return NULL;
+
+	if (length == 0)
+		return cb;
+
+	cb->buf.data = kmalloc(roundup(length, MEI_SLOT_SIZE), GFP_KERNEL);
+	if (!cb->buf.data) {
+		mei_io_cb_free(cb);
+		return NULL;
+	}
+	cb->buf.size = length;
+
+	return cb;
+}
+
+/**
+ * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
+ *     and enqueuing of the control commands cb
+ *
+ * @cl: host client
+ * @length: size of the buffer
+ * @fop_type: operation type
+ * @fp: associated file pointer (might be NULL)
+ *
+ * Return: cb on success and NULL on failure
+ * Locking: called under "dev->device_lock" lock
+ */
+struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
+					    enum mei_cb_file_ops fop_type,
+					    const struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	/* for RX always allocate at least client's mtu */
+	if (length)
+		length = max_t(size_t, length, mei_cl_mtu(cl));
+
+	cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
+	if (!cb)
+		return NULL;
+
+	list_add_tail(&cb->list, &cl->dev->ctrl_wr_list);
+	return cb;
+}
+
+/**
+ * mei_cl_read_cb - find this cl's callback in the read list
+ *     for a specific file
+ *
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ *
+ * Return: cb on success, NULL if cb is not found
+ */
+struct mei_cl_cb *mei_cl_read_cb(struct mei_cl *cl, const struct file *fp)
+{
+	struct mei_cl_cb *cb;
+	struct mei_cl_cb *ret_cb = NULL;
+
+	spin_lock(&cl->rd_completed_lock);
+	list_for_each_entry(cb, &cl->rd_completed, list)
+		if (!fp || fp == cb->fp) {
+			ret_cb = cb;
+			break;
+		}
+	spin_unlock(&cl->rd_completed_lock);
+	return ret_cb;
+}
+
+/**
+ * mei_cl_flush_queues - flushes queue lists belonging to cl.
+ *
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ *
+ * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
+ */
+int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
+{
+	struct mei_device *dev;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "remove list entry belonging to cl\n");
+	mei_io_tx_list_free_cl(&cl->dev->write_list, cl, fp);
+	mei_io_tx_list_free_cl(&cl->dev->write_waiting_list, cl, fp);
+	/* free pending and control cb only in final flush */
+	if (!fp) {
+		mei_io_list_flush_cl(&cl->dev->ctrl_wr_list, cl);
+		mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl);
+		mei_cl_free_pending(cl);
+	}
+	spin_lock(&cl->rd_completed_lock);
+	mei_io_list_free_fp(&cl->rd_completed, fp);
+	spin_unlock(&cl->rd_completed_lock);
+
+	return 0;
+}
+
+/**
+ * mei_cl_init - initializes cl.
+ *
+ * @cl: host client to be initialized
+ * @dev: mei device
+ */
+static void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
+{
+	memset(cl, 0, sizeof(*cl));
+	init_waitqueue_head(&cl->wait);
+	init_waitqueue_head(&cl->rx_wait);
+	init_waitqueue_head(&cl->tx_wait);
+	init_waitqueue_head(&cl->ev_wait);
+	INIT_LIST_HEAD(&cl->vtag_map);
+	spin_lock_init(&cl->rd_completed_lock);
+	INIT_LIST_HEAD(&cl->rd_completed);
+	INIT_LIST_HEAD(&cl->rd_pending);
+	INIT_LIST_HEAD(&cl->link);
+	cl->writing_state = MEI_IDLE;
+	cl->state = MEI_FILE_UNINITIALIZED;
+	cl->dev = dev;
+}
+
+/**
+ * mei_cl_allocate - allocates cl  structure and sets it up.
+ *
+ * @dev: mei device
+ * Return:  The allocated file or NULL on failure
+ */
+struct mei_cl *mei_cl_allocate(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	cl = kmalloc(sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return NULL;
+
+	mei_cl_init(cl, dev);
+
+	return cl;
+}
+
+/**
+ * mei_cl_link - allocate host id in the host map
+ *
+ * @cl: host client
+ *
+ * Return: 0 on success
+ *	-EINVAL on incorrect values
+ *	-EMFILE if open count exceeded.
+ */
+int mei_cl_link(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	int id;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
+	if (id >= MEI_CLIENTS_MAX) {
+		dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
+		return -EMFILE;
+	}
+
+	if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
+		dev_err(dev->dev, "open_handle_count exceeded %d",
+			MEI_MAX_OPEN_HANDLE_COUNT);
+		return -EMFILE;
+	}
+
+	dev->open_handle_count++;
+
+	cl->host_client_id = id;
+	list_add_tail(&cl->link, &dev->file_list);
+
+	set_bit(id, dev->host_clients_map);
+
+	cl->state = MEI_FILE_INITIALIZING;
+
+	cl_dbg(dev, cl, "link cl\n");
+	return 0;
+}
+
+/**
+ * mei_cl_unlink - remove host client from the list
+ *
+ * @cl: host client
+ *
+ * Return: always 0
+ */
+int mei_cl_unlink(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+
+	/* don't shout on error exit path */
+	if (!cl)
+		return 0;
+
+	if (WARN_ON(!cl->dev))
+		return 0;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "unlink client");
+
+	if (dev->open_handle_count > 0)
+		dev->open_handle_count--;
+
+	/* never clear the 0 bit */
+	if (cl->host_client_id)
+		clear_bit(cl->host_client_id, dev->host_clients_map);
+
+	list_del_init(&cl->link);
+
+	cl->state = MEI_FILE_UNINITIALIZED;
+	cl->writing_state = MEI_IDLE;
+
+	WARN_ON(!list_empty(&cl->rd_completed) ||
+		!list_empty(&cl->rd_pending) ||
+		!list_empty(&cl->link));
+
+	return 0;
+}
+
+void mei_host_client_init(struct mei_device *dev)
+{
+	mei_set_devstate(dev, MEI_DEV_ENABLED);
+	dev->reset_count = 0;
+
+	schedule_work(&dev->bus_rescan_work);
+
+	pm_runtime_mark_last_busy(dev->dev);
+	dev_dbg(dev->dev, "rpm: autosuspend\n");
+	pm_request_autosuspend(dev->dev);
+}
+
+/**
+ * mei_hbuf_acquire - try to acquire host buffer
+ *
+ * @dev: the device structure
+ * Return: true if host buffer was acquired
+ */
+bool mei_hbuf_acquire(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) == MEI_PG_ON ||
+	    mei_pg_in_transition(dev)) {
+		dev_dbg(dev->dev, "device is in pg\n");
+		return false;
+	}
+
+	if (!dev->hbuf_is_ready) {
+		dev_dbg(dev->dev, "hbuf is not ready\n");
+		return false;
+	}
+
+	dev->hbuf_is_ready = false;
+
+	return true;
+}
+
+/**
+ * mei_cl_wake_all - wake up readers, writers and event waiters so
+ *                 they can be interrupted
+ *
+ * @cl: host client
+ */
+static void mei_cl_wake_all(struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+
+	/* synchronized under device mutex */
+	if (waitqueue_active(&cl->rx_wait)) {
+		cl_dbg(dev, cl, "Waking up reading client!\n");
+		wake_up_interruptible(&cl->rx_wait);
+	}
+	/* synchronized under device mutex */
+	if (waitqueue_active(&cl->tx_wait)) {
+		cl_dbg(dev, cl, "Waking up writing client!\n");
+		wake_up_interruptible(&cl->tx_wait);
+	}
+	/* synchronized under device mutex */
+	if (waitqueue_active(&cl->ev_wait)) {
+		cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
+		wake_up_interruptible(&cl->ev_wait);
+	}
+	/* synchronized under device mutex */
+	if (waitqueue_active(&cl->wait)) {
+		cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
+		wake_up(&cl->wait);
+	}
+}
+
+/**
+ * mei_cl_set_disconnected - set disconnected state and clear
+ *   associated states and resources
+ *
+ * @cl: host client
+ */
+static void mei_cl_set_disconnected(struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+
+	if (cl->state == MEI_FILE_DISCONNECTED ||
+	    cl->state <= MEI_FILE_INITIALIZING)
+		return;
+
+	cl->state = MEI_FILE_DISCONNECTED;
+	mei_io_tx_list_free_cl(&dev->write_list, cl, NULL);
+	mei_io_tx_list_free_cl(&dev->write_waiting_list, cl, NULL);
+	mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
+	mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
+	mei_cl_wake_all(cl);
+	cl->rx_flow_ctrl_creds = 0;
+	cl->tx_flow_ctrl_creds = 0;
+	cl->timer_count = 0;
+
+	if (!cl->me_cl)
+		return;
+
+	if (!WARN_ON(cl->me_cl->connect_count == 0))
+		cl->me_cl->connect_count--;
+
+	if (cl->me_cl->connect_count == 0)
+		cl->me_cl->tx_flow_ctrl_creds = 0;
+
+	mei_me_cl_put(cl->me_cl);
+	cl->me_cl = NULL;
+}
+
+static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
+{
+	if (!mei_me_cl_get(me_cl))
+		return -ENOENT;
+
+	/* only one connection is allowed for fixed address clients */
+	if (me_cl->props.fixed_address) {
+		if (me_cl->connect_count) {
+			mei_me_cl_put(me_cl);
+			return -EBUSY;
+		}
+	}
+
+	cl->me_cl = me_cl;
+	cl->state = MEI_FILE_CONNECTING;
+	cl->me_cl->connect_count++;
+
+	return 0;
+}
+
+/*
+ * mei_cl_send_disconnect - send disconnect request
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev = cl->dev;
+
+	ret = mei_hbm_cl_disconnect_req(dev, cl);
+	cl->status = ret;
+	if (ret) {
+		cl->state = MEI_FILE_DISCONNECT_REPLY;
+		return ret;
+	}
+
+	list_move_tail(&cb->list, &dev->ctrl_rd_list);
+	cl->timer_count = MEI_CONNECT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+
+	return 0;
+}
+
+/**
+ * mei_cl_irq_disconnect - processes close related operation from
+ *	interrupt thread context - send disconnect request
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
+			  struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	ret = mei_cl_send_disconnect(cl, cb);
+	if (ret)
+		list_move_tail(&cb->list, cmpl_list);
+
+	return ret;
+}
+
+/**
+ * __mei_cl_disconnect - disconnect host client from the me one
+ *     internal function runtime pm has to be already acquired
+ *
+ * @cl: host client
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int __mei_cl_disconnect(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	int rets;
+
+	dev = cl->dev;
+
+	cl->state = MEI_FILE_DISCONNECTING;
+
+	cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
+
+	if (mei_hbuf_acquire(dev)) {
+		rets = mei_cl_send_disconnect(cl, cb);
+		if (rets) {
+			cl_err(dev, cl, "failed to disconnect.\n");
+			goto out;
+		}
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(cl->wait,
+			   cl->state == MEI_FILE_DISCONNECT_REPLY ||
+			   cl->state == MEI_FILE_DISCONNECTED,
+			   mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	rets = cl->status;
+	if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
+	    cl->state != MEI_FILE_DISCONNECTED) {
+		cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
+		rets = -ETIME;
+	}
+
+out:
+	/* we disconnect also on error */
+	mei_cl_set_disconnected(cl);
+	if (!rets)
+		cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
+
+	mei_io_cb_free(cb);
+	return rets;
+}
+
+/**
+ * mei_cl_disconnect - disconnect host client from the me one
+ *
+ * @cl: host client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_disconnect(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "disconnecting");
+
+	if (!mei_cl_is_connected(cl))
+		return 0;
+
+	if (mei_cl_is_fixed_address(cl)) {
+		mei_cl_set_disconnected(cl);
+		return 0;
+	}
+
+	if (dev->dev_state == MEI_DEV_POWER_DOWN) {
+		cl_dbg(dev, cl, "Device is powering down, don't bother with disconnection\n");
+		mei_cl_set_disconnected(cl);
+		return 0;
+	}
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	rets = __mei_cl_disconnect(cl);
+
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	return rets;
+}
+
+
+/**
+ * mei_cl_is_other_connecting - checks if other
+ *    client with the same me client id is connecting
+ *
+ * @cl: private data of the file object
+ *
+ * Return: true if other client is connected, false - otherwise.
+ */
+static bool mei_cl_is_other_connecting(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+
+	dev = cl->dev;
+
+	list_for_each_entry(cb, &dev->ctrl_rd_list, list) {
+		if (cb->fop_type == MEI_FOP_CONNECT &&
+		    mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * mei_cl_send_connect - send connect request
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev = cl->dev;
+
+	ret = mei_hbm_cl_connect_req(dev, cl);
+	cl->status = ret;
+	if (ret) {
+		cl->state = MEI_FILE_DISCONNECT_REPLY;
+		return ret;
+	}
+
+	list_move_tail(&cb->list, &dev->ctrl_rd_list);
+	cl->timer_count = MEI_CONNECT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_cl_irq_connect - send connect request in irq_thread context
+ *
+ * @cl: host client
+ * @cb: callback block
+ * @cmpl_list: complete list
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
+		       struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int rets;
+
+	if (mei_cl_is_other_connecting(cl))
+		return 0;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	rets = mei_cl_send_connect(cl, cb);
+	if (rets)
+		list_move_tail(&cb->list, cmpl_list);
+
+	return rets;
+}
+
+/**
+ * mei_cl_connect - connect host client to the me one
+ *
+ * @cl: host client
+ * @me_cl: me client
+ * @fp: pointer to file structure
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
+		   const struct file *fp)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev || !me_cl))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	rets = mei_cl_set_connecting(cl, me_cl);
+	if (rets)
+		goto nortpm;
+
+	if (mei_cl_is_fixed_address(cl)) {
+		cl->state = MEI_FILE_CONNECTED;
+		rets = 0;
+		goto nortpm;
+	}
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		goto nortpm;
+	}
+
+	cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
+
+	/* run hbuf acquire last so we don't have to undo */
+	if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
+		rets = mei_cl_send_connect(cl, cb);
+		if (rets)
+			goto out;
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(cl->wait,
+			(cl->state == MEI_FILE_CONNECTED ||
+			 cl->state == MEI_FILE_DISCONNECTED ||
+			 cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
+			 cl->state == MEI_FILE_DISCONNECT_REPLY),
+			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	if (!mei_cl_is_connected(cl)) {
+		if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
+			mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
+			mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
+			 /* ignore disconnect return valuue;
+			  * in case of failure reset will be invoked
+			  */
+			__mei_cl_disconnect(cl);
+			rets = -EFAULT;
+			goto out;
+		}
+
+		/* timeout or something went really wrong */
+		if (!cl->status)
+			cl->status = -EFAULT;
+	}
+
+	rets = cl->status;
+out:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	mei_io_cb_free(cb);
+
+nortpm:
+	if (!mei_cl_is_connected(cl))
+		mei_cl_set_disconnected(cl);
+
+	return rets;
+}
+
+/**
+ * mei_cl_alloc_linked - allocate and link host client
+ *
+ * @dev: the device structure
+ *
+ * Return: cl on success ERR_PTR on failure
+ */
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+	int ret;
+
+	cl = mei_cl_allocate(dev);
+	if (!cl) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ret = mei_cl_link(cl);
+	if (ret)
+		goto err;
+
+	return cl;
+err:
+	kfree(cl);
+	return ERR_PTR(ret);
+}
+
+/**
+ * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
+ *
+ * @cl: host client
+ *
+ * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
+ */
+static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
+{
+	if (WARN_ON(!cl || !cl->me_cl))
+		return -EINVAL;
+
+	if (cl->tx_flow_ctrl_creds > 0)
+		return 1;
+
+	if (mei_cl_is_fixed_address(cl))
+		return 1;
+
+	if (mei_cl_is_single_recv_buf(cl)) {
+		if (cl->me_cl->tx_flow_ctrl_creds > 0)
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
+ *   for a client
+ *
+ * @cl: host client
+ *
+ * Return:
+ *	0 on success
+ *	-EINVAL when ctrl credits are <= 0
+ */
+static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
+{
+	if (WARN_ON(!cl || !cl->me_cl))
+		return -EINVAL;
+
+	if (mei_cl_is_fixed_address(cl))
+		return 0;
+
+	if (mei_cl_is_single_recv_buf(cl)) {
+		if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
+			return -EINVAL;
+		cl->me_cl->tx_flow_ctrl_creds--;
+	} else {
+		if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
+			return -EINVAL;
+		cl->tx_flow_ctrl_creds--;
+	}
+	return 0;
+}
+
+/**
+ * mei_cl_vtag_alloc - allocate and fill the vtag structure
+ *
+ * @fp: pointer to file structure
+ * @vtag: vm tag
+ *
+ * Return:
+ * * Pointer to allocated struct - on success
+ * * ERR_PTR(-ENOMEM) on memory allocation failure
+ */
+struct mei_cl_vtag *mei_cl_vtag_alloc(struct file *fp, u8 vtag)
+{
+	struct mei_cl_vtag *cl_vtag;
+
+	cl_vtag = kzalloc(sizeof(*cl_vtag), GFP_KERNEL);
+	if (!cl_vtag)
+		return ERR_PTR(-ENOMEM);
+
+	INIT_LIST_HEAD(&cl_vtag->list);
+	cl_vtag->vtag = vtag;
+	cl_vtag->fp = fp;
+
+	return cl_vtag;
+}
+
+/**
+ * mei_cl_fp_by_vtag - obtain the file pointer by vtag
+ *
+ * @cl: host client
+ * @vtag: vm tag
+ *
+ * Return:
+ * * A file pointer - on success
+ * * ERR_PTR(-ENOENT) if vtag is not found in the client vtag list
+ */
+const struct file *mei_cl_fp_by_vtag(const struct mei_cl *cl, u8 vtag)
+{
+	struct mei_cl_vtag *vtag_l;
+
+	list_for_each_entry(vtag_l, &cl->vtag_map, list)
+		if (vtag_l->vtag == vtag)
+			return vtag_l->fp;
+
+	return ERR_PTR(-ENOENT);
+}
+
+/**
+ * mei_cl_reset_read_by_vtag - reset pending_read flag by given vtag
+ *
+ * @cl: host client
+ * @vtag: vm tag
+ */
+static void mei_cl_reset_read_by_vtag(const struct mei_cl *cl, u8 vtag)
+{
+	struct mei_cl_vtag *vtag_l;
+
+	list_for_each_entry(vtag_l, &cl->vtag_map, list) {
+		if (vtag_l->vtag == vtag) {
+			vtag_l->pending_read = false;
+			break;
+		}
+	}
+}
+
+/**
+ * mei_cl_read_vtag_add_fc - add flow control for next pending reader
+ *                           in the vtag list
+ *
+ * @cl: host client
+ */
+static void mei_cl_read_vtag_add_fc(struct mei_cl *cl)
+{
+	struct mei_cl_vtag *cl_vtag;
+
+	list_for_each_entry(cl_vtag, &cl->vtag_map, list) {
+		if (cl_vtag->pending_read) {
+			if (mei_cl_enqueue_ctrl_wr_cb(cl,
+						      mei_cl_mtu(cl),
+						      MEI_FOP_READ,
+						      cl_vtag->fp))
+				cl->rx_flow_ctrl_creds++;
+			break;
+		}
+	}
+}
+
+/**
+ * mei_cl_vt_support_check - check if client support vtags
+ *
+ * @cl: host client
+ *
+ * Return:
+ * * 0 - supported, or not connected at all
+ * * -EOPNOTSUPP - vtags are not supported by client
+ */
+int mei_cl_vt_support_check(const struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+
+	if (!dev->hbm_f_vt_supported)
+		return -EOPNOTSUPP;
+
+	if (!cl->me_cl)
+		return 0;
+
+	return cl->me_cl->props.vt_supported ? 0 : -EOPNOTSUPP;
+}
+
+/**
+ * mei_cl_add_rd_completed - add read completed callback to list with lock
+ *                           and vtag check
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ */
+void mei_cl_add_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	const struct file *fp;
+
+	if (!mei_cl_vt_support_check(cl)) {
+		fp = mei_cl_fp_by_vtag(cl, cb->vtag);
+		if (IS_ERR(fp)) {
+			/* client already disconnected, discarding */
+			mei_io_cb_free(cb);
+			return;
+		}
+		cb->fp = fp;
+		mei_cl_reset_read_by_vtag(cl, cb->vtag);
+		mei_cl_read_vtag_add_fc(cl);
+	}
+
+	spin_lock(&cl->rd_completed_lock);
+	list_add_tail(&cb->list, &cl->rd_completed);
+	spin_unlock(&cl->rd_completed_lock);
+}
+
+/**
+ * mei_cl_del_rd_completed - free read completed callback with lock
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ */
+void mei_cl_del_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	spin_lock(&cl->rd_completed_lock);
+	mei_io_cb_free(cb);
+	spin_unlock(&cl->rd_completed_lock);
+}
+
+/**
+ *  mei_cl_notify_fop2req - convert fop to proper request
+ *
+ * @fop: client notification start response command
+ *
+ * Return:  MEI_HBM_NOTIFICATION_START/STOP
+ */
+u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
+{
+	if (fop == MEI_FOP_NOTIFY_START)
+		return MEI_HBM_NOTIFICATION_START;
+	else
+		return MEI_HBM_NOTIFICATION_STOP;
+}
+
+/**
+ *  mei_cl_notify_req2fop - convert notification request top file operation type
+ *
+ * @req: hbm notification request type
+ *
+ * Return:  MEI_FOP_NOTIFY_START/STOP
+ */
+enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
+{
+	if (req == MEI_HBM_NOTIFICATION_START)
+		return MEI_FOP_NOTIFY_START;
+	else
+		return MEI_FOP_NOTIFY_STOP;
+}
+
+/**
+ * mei_cl_irq_notify - send notification request in irq_thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
+		      struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+	bool request;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	request = mei_cl_notify_fop2req(cb->fop_type);
+	ret = mei_hbm_cl_notify_req(dev, cl, request);
+	if (ret) {
+		cl->status = ret;
+		list_move_tail(&cb->list, cmpl_list);
+		return ret;
+	}
+
+	list_move_tail(&cb->list, &dev->ctrl_rd_list);
+	return 0;
+}
+
+/**
+ * mei_cl_notify_request - send notification stop/start request
+ *
+ * @cl: host client
+ * @fp: associate request with file
+ * @request: 1 for start or 0 for stop
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_notify_request(struct mei_cl *cl,
+			  const struct file *fp, u8 request)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	enum mei_cb_file_ops fop_type;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	if (!dev->hbm_f_ev_supported) {
+		cl_dbg(dev, cl, "notifications not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (!mei_cl_is_connected(cl))
+		return -ENODEV;
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	fop_type = mei_cl_notify_req2fop(request);
+	cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
+
+	if (mei_hbuf_acquire(dev)) {
+		if (mei_hbm_cl_notify_req(dev, cl, request)) {
+			rets = -ENODEV;
+			goto out;
+		}
+		list_move_tail(&cb->list, &dev->ctrl_rd_list);
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(cl->wait,
+			   cl->notify_en == request ||
+			   cl->status ||
+			   !mei_cl_is_connected(cl),
+			   mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	if (cl->notify_en != request && !cl->status)
+		cl->status = -EFAULT;
+
+	rets = cl->status;
+
+out:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	mei_io_cb_free(cb);
+	return rets;
+}
+
+/**
+ * mei_cl_notify - raise notification
+ *
+ * @cl: host client
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_cl_notify(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+
+	if (!cl || !cl->dev)
+		return;
+
+	dev = cl->dev;
+
+	if (!cl->notify_en)
+		return;
+
+	cl_dbg(dev, cl, "notify event");
+	cl->notify_ev = true;
+	if (!mei_cl_bus_notify_event(cl))
+		wake_up_interruptible(&cl->ev_wait);
+
+	if (cl->ev_async)
+		kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
+
+}
+
+/**
+ * mei_cl_notify_get - get or wait for notification event
+ *
+ * @cl: host client
+ * @block: this request is blocking
+ * @notify_ev: true if notification event was received
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
+{
+	struct mei_device *dev;
+	int rets;
+
+	*notify_ev = false;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	if (!dev->hbm_f_ev_supported) {
+		cl_dbg(dev, cl, "notifications not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (!mei_cl_is_connected(cl))
+		return -ENODEV;
+
+	if (cl->notify_ev)
+		goto out;
+
+	if (!block)
+		return -EAGAIN;
+
+	mutex_unlock(&dev->device_lock);
+	rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
+	mutex_lock(&dev->device_lock);
+
+	if (rets < 0)
+		return rets;
+
+out:
+	*notify_ev = cl->notify_ev;
+	cl->notify_ev = false;
+	return 0;
+}
+
+/**
+ * mei_cl_read_start - the start read client message function.
+ *
+ * @cl: host client
+ * @length: number of bytes to read
+ * @fp: pointer to file structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	if (!mei_cl_is_connected(cl))
+		return -ENODEV;
+
+	if (!mei_me_cl_is_active(cl->me_cl)) {
+		cl_err(dev, cl, "no such me client\n");
+		return  -ENOTTY;
+	}
+
+	if (mei_cl_is_fixed_address(cl))
+		return 0;
+
+	/* HW currently supports only one pending read */
+	if (cl->rx_flow_ctrl_creds) {
+		mei_cl_set_read_by_fp(cl, fp);
+		return -EBUSY;
+	}
+
+	cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
+	if (!cb)
+		return -ENOMEM;
+
+	mei_cl_set_read_by_fp(cl, fp);
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		goto nortpm;
+	}
+
+	rets = 0;
+	if (mei_hbuf_acquire(dev)) {
+		rets = mei_hbm_cl_flow_control_req(dev, cl);
+		if (rets < 0)
+			goto out;
+
+		list_move_tail(&cb->list, &cl->rd_pending);
+	}
+	cl->rx_flow_ctrl_creds++;
+
+out:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+nortpm:
+	if (rets)
+		mei_io_cb_free(cb);
+
+	return rets;
+}
+
+static inline u8 mei_ext_hdr_set_vtag(struct mei_ext_hdr *ext, u8 vtag)
+{
+	ext->type = MEI_EXT_HDR_VTAG;
+	ext->ext_payload[0] = vtag;
+	ext->length = mei_data2slots(sizeof(*ext));
+	return ext->length;
+}
+
+/**
+ * mei_msg_hdr_init - allocate and initialize mei message header
+ *
+ * @cb: message callback structure
+ *
+ * Return: a pointer to initialized header
+ */
+static struct mei_msg_hdr *mei_msg_hdr_init(const struct mei_cl_cb *cb)
+{
+	size_t hdr_len;
+	struct mei_ext_meta_hdr *meta;
+	struct mei_ext_hdr *ext;
+	struct mei_msg_hdr *mei_hdr;
+	bool is_ext, is_vtag;
+
+	if (!cb)
+		return ERR_PTR(-EINVAL);
+
+	/* Extended header for vtag is attached only on the first fragment */
+	is_vtag = (cb->vtag && cb->buf_idx == 0);
+	is_ext = is_vtag;
+
+	/* Compute extended header size */
+	hdr_len = sizeof(*mei_hdr);
+
+	if (!is_ext)
+		goto setup_hdr;
+
+	hdr_len += sizeof(*meta);
+	if (is_vtag)
+		hdr_len += sizeof(*ext);
+
+setup_hdr:
+	mei_hdr = kzalloc(hdr_len, GFP_KERNEL);
+	if (!mei_hdr)
+		return ERR_PTR(-ENOMEM);
+
+	mei_hdr->host_addr = mei_cl_host_addr(cb->cl);
+	mei_hdr->me_addr = mei_cl_me_id(cb->cl);
+	mei_hdr->internal = cb->internal;
+	mei_hdr->extended = is_ext;
+
+	if (!is_ext)
+		goto out;
+
+	meta = (struct mei_ext_meta_hdr *)mei_hdr->extension;
+	if (is_vtag) {
+		meta->count++;
+		meta->size += mei_ext_hdr_set_vtag(meta->hdrs, cb->vtag);
+	}
+out:
+	mei_hdr->length = hdr_len - sizeof(*mei_hdr);
+	return mei_hdr;
+}
+
+/**
+ * mei_cl_irq_write - write a message to device
+ *	from the interrupt thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise error.
+ */
+int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
+		     struct list_head *cmpl_list)
+{
+	struct mei_device *dev;
+	struct mei_msg_data *buf;
+	struct mei_msg_hdr *mei_hdr = NULL;
+	size_t hdr_len;
+	size_t hbuf_len, dr_len;
+	size_t buf_len;
+	size_t data_len;
+	int hbuf_slots;
+	u32 dr_slots;
+	u32 dma_len;
+	int rets;
+	bool first_chunk;
+	const void *data;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	buf = &cb->buf;
+
+	first_chunk = cb->buf_idx == 0;
+
+	rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
+	if (rets < 0)
+		goto err;
+
+	if (rets == 0) {
+		cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
+		return 0;
+	}
+
+	buf_len = buf->size - cb->buf_idx;
+	data = buf->data + cb->buf_idx;
+	hbuf_slots = mei_hbuf_empty_slots(dev);
+	if (hbuf_slots < 0) {
+		rets = -EOVERFLOW;
+		goto err;
+	}
+
+	hbuf_len = mei_slots2data(hbuf_slots) & MEI_MSG_MAX_LEN_MASK;
+	dr_slots = mei_dma_ring_empty_slots(dev);
+	dr_len = mei_slots2data(dr_slots);
+
+	mei_hdr = mei_msg_hdr_init(cb);
+	if (IS_ERR(mei_hdr)) {
+		rets = PTR_ERR(mei_hdr);
+		mei_hdr = NULL;
+		goto err;
+	}
+
+	cl_dbg(dev, cl, "Extended Header %d vtag = %d\n",
+	       mei_hdr->extended, cb->vtag);
+
+	hdr_len = sizeof(*mei_hdr) + mei_hdr->length;
+
+	/**
+	 * Split the message only if we can write the whole host buffer
+	 * otherwise wait for next time the host buffer is empty.
+	 */
+	if (hdr_len + buf_len <= hbuf_len) {
+		data_len = buf_len;
+		mei_hdr->msg_complete = 1;
+	} else if (dr_slots && hbuf_len >= hdr_len + sizeof(dma_len)) {
+		mei_hdr->dma_ring = 1;
+		if (buf_len > dr_len)
+			buf_len = dr_len;
+		else
+			mei_hdr->msg_complete = 1;
+
+		data_len = sizeof(dma_len);
+		dma_len = buf_len;
+		data = &dma_len;
+	} else if ((u32)hbuf_slots == mei_hbuf_depth(dev)) {
+		buf_len = hbuf_len - hdr_len;
+		data_len = buf_len;
+	} else {
+		kfree(mei_hdr);
+		return 0;
+	}
+	mei_hdr->length += data_len;
+
+	if (mei_hdr->dma_ring)
+		mei_dma_ring_write(dev, buf->data + cb->buf_idx, buf_len);
+	rets = mei_write_message(dev, mei_hdr, hdr_len, data, data_len);
+
+	if (rets)
+		goto err;
+
+	cl->status = 0;
+	cl->writing_state = MEI_WRITING;
+	cb->buf_idx += buf_len;
+
+	if (first_chunk) {
+		if (mei_cl_tx_flow_ctrl_creds_reduce(cl)) {
+			rets = -EIO;
+			goto err;
+		}
+	}
+
+	if (mei_hdr->msg_complete)
+		list_move_tail(&cb->list, &dev->write_waiting_list);
+
+	kfree(mei_hdr);
+	return 0;
+
+err:
+	kfree(mei_hdr);
+	cl->status = rets;
+	list_move_tail(&cb->list, cmpl_list);
+	return rets;
+}
+
+/**
+ * mei_cl_write - submit a write cb to mei device
+ *	assumes device_lock is locked
+ *
+ * @cl: host client
+ * @cb: write callback with filled data
+ *
+ * Return: number of bytes sent on success, <0 on failure.
+ */
+ssize_t mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	struct mei_device *dev;
+	struct mei_msg_data *buf;
+	struct mei_msg_hdr *mei_hdr = NULL;
+	size_t hdr_len;
+	size_t hbuf_len, dr_len;
+	size_t buf_len;
+	size_t data_len;
+	int hbuf_slots;
+	u32 dr_slots;
+	u32 dma_len;
+	ssize_t rets;
+	bool blocking;
+	const void *data;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	if (WARN_ON(!cb))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	buf = &cb->buf;
+	buf_len = buf->size;
+
+	cl_dbg(dev, cl, "buf_len=%zd\n", buf_len);
+
+	blocking = cb->blocking;
+	data = buf->data;
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %zd\n", rets);
+		goto free;
+	}
+
+	cb->buf_idx = 0;
+	cl->writing_state = MEI_IDLE;
+
+
+	rets = mei_cl_tx_flow_ctrl_creds(cl);
+	if (rets < 0)
+		goto err;
+
+	mei_hdr = mei_msg_hdr_init(cb);
+	if (IS_ERR(mei_hdr)) {
+		rets = PTR_ERR(mei_hdr);
+		mei_hdr = NULL;
+		goto err;
+	}
+
+	cl_dbg(dev, cl, "Extended Header %d vtag = %d\n",
+	       mei_hdr->extended, cb->vtag);
+
+	hdr_len = sizeof(*mei_hdr) + mei_hdr->length;
+
+	if (rets == 0) {
+		cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
+		rets = buf_len;
+		goto out;
+	}
+
+	if (!mei_hbuf_acquire(dev)) {
+		cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
+		rets = buf_len;
+		goto out;
+	}
+
+	hbuf_slots = mei_hbuf_empty_slots(dev);
+	if (hbuf_slots < 0) {
+		buf_len = -EOVERFLOW;
+		goto out;
+	}
+
+	hbuf_len = mei_slots2data(hbuf_slots) & MEI_MSG_MAX_LEN_MASK;
+	dr_slots = mei_dma_ring_empty_slots(dev);
+	dr_len =  mei_slots2data(dr_slots);
+
+	if (hdr_len + buf_len <= hbuf_len) {
+		data_len = buf_len;
+		mei_hdr->msg_complete = 1;
+	} else if (dr_slots && hbuf_len >= hdr_len + sizeof(dma_len)) {
+		mei_hdr->dma_ring = 1;
+		if (buf_len > dr_len)
+			buf_len = dr_len;
+		else
+			mei_hdr->msg_complete = 1;
+
+		data_len = sizeof(dma_len);
+		dma_len = buf_len;
+		data = &dma_len;
+	} else {
+		buf_len = hbuf_len - hdr_len;
+		data_len = buf_len;
+	}
+
+	mei_hdr->length += data_len;
+
+	if (mei_hdr->dma_ring)
+		mei_dma_ring_write(dev, buf->data, buf_len);
+	rets = mei_write_message(dev, mei_hdr, hdr_len, data, data_len);
+
+	if (rets)
+		goto err;
+
+	rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
+	if (rets)
+		goto err;
+
+	cl->writing_state = MEI_WRITING;
+	cb->buf_idx = buf_len;
+	/* restore return value */
+	buf_len = buf->size;
+
+out:
+	if (mei_hdr->msg_complete)
+		mei_tx_cb_enqueue(cb, &dev->write_waiting_list);
+	else
+		mei_tx_cb_enqueue(cb, &dev->write_list);
+
+	cb = NULL;
+	if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
+
+		mutex_unlock(&dev->device_lock);
+		rets = wait_event_interruptible(cl->tx_wait,
+				cl->writing_state == MEI_WRITE_COMPLETE ||
+				(!mei_cl_is_connected(cl)));
+		mutex_lock(&dev->device_lock);
+		/* wait_event_interruptible returns -ERESTARTSYS */
+		if (rets) {
+			if (signal_pending(current))
+				rets = -EINTR;
+			goto err;
+		}
+		if (cl->writing_state != MEI_WRITE_COMPLETE) {
+			rets = -EFAULT;
+			goto err;
+		}
+	}
+
+	rets = buf_len;
+err:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+free:
+	mei_io_cb_free(cb);
+
+	kfree(mei_hdr);
+
+	return rets;
+}
+
+/**
+ * mei_cl_complete - processes completed operation for a client
+ *
+ * @cl: private data of the file object.
+ * @cb: callback block.
+ */
+void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	struct mei_device *dev = cl->dev;
+
+	switch (cb->fop_type) {
+	case MEI_FOP_WRITE:
+		mei_tx_cb_dequeue(cb);
+		cl->writing_state = MEI_WRITE_COMPLETE;
+		if (waitqueue_active(&cl->tx_wait)) {
+			wake_up_interruptible(&cl->tx_wait);
+		} else {
+			pm_runtime_mark_last_busy(dev->dev);
+			pm_request_autosuspend(dev->dev);
+		}
+		break;
+
+	case MEI_FOP_READ:
+		mei_cl_add_rd_completed(cl, cb);
+		if (!mei_cl_is_fixed_address(cl) &&
+		    !WARN_ON(!cl->rx_flow_ctrl_creds))
+			cl->rx_flow_ctrl_creds--;
+		if (!mei_cl_bus_rx_event(cl))
+			wake_up_interruptible(&cl->rx_wait);
+		break;
+
+	case MEI_FOP_CONNECT:
+	case MEI_FOP_DISCONNECT:
+	case MEI_FOP_NOTIFY_STOP:
+	case MEI_FOP_NOTIFY_START:
+		if (waitqueue_active(&cl->wait))
+			wake_up(&cl->wait);
+
+		break;
+	case MEI_FOP_DISCONNECT_RSP:
+		mei_io_cb_free(cb);
+		mei_cl_set_disconnected(cl);
+		break;
+	default:
+		BUG_ON(0);
+	}
+}
+
+
+/**
+ * mei_cl_all_disconnect - disconnect forcefully all connected clients
+ *
+ * @dev: mei device
+ */
+void mei_cl_all_disconnect(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->file_list, link)
+		mei_cl_set_disconnected(cl);
+}
diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h
new file mode 100644
index 000000000..9e08a9843
--- /dev/null
+++ b/drivers/misc/mei/client.h
@@ -0,0 +1,280 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_CLIENT_H_
+#define _MEI_CLIENT_H_
+
+#include <linux/types.h>
+#include <linux/poll.h>
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+
+/*
+ * reference counting base function
+ */
+void mei_me_cl_init(struct mei_me_client *me_cl);
+void mei_me_cl_put(struct mei_me_client *me_cl);
+struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl);
+
+void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl);
+void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl);
+
+struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid);
+struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id);
+struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id);
+void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid);
+void mei_me_cl_rm_by_uuid_id(struct mei_device *dev,
+			     const uuid_le *uuid, u8 id);
+void mei_me_cl_rm_all(struct mei_device *dev);
+
+/**
+ * mei_me_cl_is_active - check whether me client is active in the fw
+ *
+ * @me_cl: me client
+ *
+ * Return: true if the me client is active in the firmware
+ */
+static inline bool mei_me_cl_is_active(const struct mei_me_client *me_cl)
+{
+	return !list_empty_careful(&me_cl->list);
+}
+
+/**
+ * mei_me_cl_uuid - return me client protocol name (uuid)
+ *
+ * @me_cl: me client
+ *
+ * Return: me client protocol name
+ */
+static inline const uuid_le *mei_me_cl_uuid(const struct mei_me_client *me_cl)
+{
+	return &me_cl->props.protocol_name;
+}
+
+/**
+ * mei_me_cl_ver - return me client protocol version
+ *
+ * @me_cl: me client
+ *
+ * Return: me client protocol version
+ */
+static inline u8 mei_me_cl_ver(const struct mei_me_client *me_cl)
+{
+	return me_cl->props.protocol_version;
+}
+
+/**
+ * mei_me_cl_max_conn - return me client max number of connections
+ *
+ * @me_cl: me client
+ *
+ * Return: me client max number of connections
+ */
+static inline u8 mei_me_cl_max_conn(const struct mei_me_client *me_cl)
+{
+	return me_cl->props.max_number_of_connections;
+}
+
+/**
+ * mei_me_cl_fixed - return me client fixed address, if any
+ *
+ * @me_cl: me client
+ *
+ * Return: me client fixed address
+ */
+static inline u8 mei_me_cl_fixed(const struct mei_me_client *me_cl)
+{
+	return me_cl->props.fixed_address;
+}
+
+/**
+ * mei_me_cl_vt - return me client vtag supported status
+ *
+ * @me_cl: me client
+ *
+ * Return: true if me client supports vt tagging
+ */
+static inline bool mei_me_cl_vt(const struct mei_me_client *me_cl)
+{
+	return me_cl->props.vt_supported == 1;
+}
+
+/**
+ * mei_me_cl_max_len - return me client max msg length
+ *
+ * @me_cl: me client
+ *
+ * Return: me client max msg length
+ */
+static inline u32 mei_me_cl_max_len(const struct mei_me_client *me_cl)
+{
+	return me_cl->props.max_msg_length;
+}
+
+/*
+ * MEI IO Functions
+ */
+void mei_io_cb_free(struct mei_cl_cb *priv_cb);
+
+/*
+ * MEI Host Client Functions
+ */
+
+struct mei_cl *mei_cl_allocate(struct mei_device *dev);
+
+int mei_cl_link(struct mei_cl *cl);
+int mei_cl_unlink(struct mei_cl *cl);
+
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev);
+
+struct mei_cl_cb *mei_cl_read_cb(struct mei_cl *cl, const struct file *fp);
+
+void mei_cl_add_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb);
+void mei_cl_del_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb);
+
+struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
+				  enum mei_cb_file_ops type,
+				  const struct file *fp);
+struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
+					    enum mei_cb_file_ops type,
+					    const struct file *fp);
+int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp);
+
+struct mei_cl_vtag *mei_cl_vtag_alloc(struct file *fp, u8 vtag);
+const struct file *mei_cl_fp_by_vtag(const struct mei_cl *cl, u8 vtag);
+int mei_cl_vt_support_check(const struct mei_cl *cl);
+/*
+ *  MEI input output function prototype
+ */
+
+/**
+ * mei_cl_is_connected - host client is connected
+ *
+ * @cl: host client
+ *
+ * Return: true if the host client is connected
+ */
+static inline bool mei_cl_is_connected(struct mei_cl *cl)
+{
+	return  cl->state == MEI_FILE_CONNECTED;
+}
+
+/**
+ * mei_cl_me_id - me client id
+ *
+ * @cl: host client
+ *
+ * Return: me client id or 0 if client is not connected
+ */
+static inline u8 mei_cl_me_id(const struct mei_cl *cl)
+{
+	return cl->me_cl ? cl->me_cl->client_id : 0;
+}
+
+/**
+ * mei_cl_mtu - maximal message that client can send and receive
+ *
+ * @cl: host client
+ *
+ * Return: mtu or 0 if client is not connected
+ */
+static inline size_t mei_cl_mtu(const struct mei_cl *cl)
+{
+	return cl->me_cl ? cl->me_cl->props.max_msg_length : 0;
+}
+
+/**
+ * mei_cl_is_fixed_address - check whether the me client uses fixed address
+ *
+ * @cl: host client
+ *
+ * Return: true if the client is connected and it has fixed me address
+ */
+static inline bool mei_cl_is_fixed_address(const struct mei_cl *cl)
+{
+	return cl->me_cl && cl->me_cl->props.fixed_address;
+}
+
+/**
+ * mei_cl_is_single_recv_buf- check whether the me client
+ *       uses single receiving buffer
+ *
+ * @cl: host client
+ *
+ * Return: true if single_recv_buf == 1; 0 otherwise
+ */
+static inline bool mei_cl_is_single_recv_buf(const struct mei_cl *cl)
+{
+	return cl->me_cl->props.single_recv_buf;
+}
+
+/**
+ * mei_cl_uuid -  client's uuid
+ *
+ * @cl: host client
+ *
+ * Return: return uuid of connected me client
+ */
+static inline const uuid_le *mei_cl_uuid(const struct mei_cl *cl)
+{
+	return mei_me_cl_uuid(cl->me_cl);
+}
+
+/**
+ * mei_cl_host_addr - client's host address
+ *
+ * @cl: host client
+ *
+ * Return: 0 for fixed address client, host address for dynamic client
+ */
+static inline u8 mei_cl_host_addr(const struct mei_cl *cl)
+{
+	return  mei_cl_is_fixed_address(cl) ? 0 : cl->host_client_id;
+}
+
+int mei_cl_disconnect(struct mei_cl *cl);
+int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
+			  struct list_head *cmpl_list);
+int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
+		   const struct file *file);
+int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
+		       struct list_head *cmpl_list);
+int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp);
+ssize_t mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb);
+int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
+		     struct list_head *cmpl_list);
+
+void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb);
+
+void mei_host_client_init(struct mei_device *dev);
+
+u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop);
+enum mei_cb_file_ops mei_cl_notify_req2fop(u8 request);
+int mei_cl_notify_request(struct mei_cl *cl,
+			  const struct file *file, u8 request);
+int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
+		      struct list_head *cmpl_list);
+int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev);
+void mei_cl_notify(struct mei_cl *cl);
+
+void mei_cl_all_disconnect(struct mei_device *dev);
+
+#define MEI_CL_FMT "cl:host=%02d me=%02d "
+#define MEI_CL_PRM(cl) (cl)->host_client_id, mei_cl_me_id(cl)
+
+#define cl_dbg(dev, cl, format, arg...) \
+	dev_dbg((dev)->dev, MEI_CL_FMT format, MEI_CL_PRM(cl), ##arg)
+
+#define cl_warn(dev, cl, format, arg...) \
+	dev_warn((dev)->dev, MEI_CL_FMT format, MEI_CL_PRM(cl), ##arg)
+
+#define cl_err(dev, cl, format, arg...) \
+	dev_err((dev)->dev, MEI_CL_FMT format, MEI_CL_PRM(cl), ##arg)
+
+#endif /* _MEI_CLIENT_H_ */
diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
new file mode 100644
index 000000000..3ab1a431d
--- /dev/null
+++ b/drivers/misc/mei/debugfs.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2016, Intel Corporation. All rights reserved
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "client.h"
+#include "hw.h"
+
+static int mei_dbgfs_meclients_show(struct seq_file *m, void *unused)
+{
+	struct mei_device *dev = m->private;
+	struct mei_me_client *me_cl;
+	int i = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	down_read(&dev->me_clients_rwsem);
+
+	seq_puts(m, "  |id|fix|         UUID                       |con|msg len|sb|refc|vt|\n");
+
+	/*  if the driver is not enabled the list won't be consistent */
+	if (dev->dev_state != MEI_DEV_ENABLED)
+		goto out;
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		if (!mei_me_cl_get(me_cl))
+			continue;
+
+		seq_printf(m, "%2d|%2d|%3d|%pUl|%3d|%7d|%2d|%4d|%2d|\n",
+			   i++, me_cl->client_id,
+			   me_cl->props.fixed_address,
+			   &me_cl->props.protocol_name,
+			   me_cl->props.max_number_of_connections,
+			   me_cl->props.max_msg_length,
+			   me_cl->props.single_recv_buf,
+			   kref_read(&me_cl->refcnt),
+			   me_cl->props.vt_supported);
+		mei_me_cl_put(me_cl);
+	}
+
+out:
+	up_read(&dev->me_clients_rwsem);
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(mei_dbgfs_meclients);
+
+static int mei_dbgfs_active_show(struct seq_file *m, void *unused)
+{
+	struct mei_device *dev = m->private;
+	struct mei_cl *cl;
+	int i = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	seq_puts(m, "   |me|host|state|rd|wr|wrq\n");
+
+	/*  if the driver is not enabled the list won't be consistent */
+	if (dev->dev_state != MEI_DEV_ENABLED)
+		goto out;
+
+	list_for_each_entry(cl, &dev->file_list, link) {
+
+		seq_printf(m, "%3d|%2d|%4d|%5d|%2d|%2d|%3u\n",
+			   i, mei_cl_me_id(cl), cl->host_client_id, cl->state,
+			   !list_empty(&cl->rd_completed), cl->writing_state,
+			   cl->tx_cb_queued);
+		i++;
+	}
+out:
+	mutex_unlock(&dev->device_lock);
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(mei_dbgfs_active);
+
+static int mei_dbgfs_devstate_show(struct seq_file *m, void *unused)
+{
+	struct mei_device *dev = m->private;
+
+	seq_printf(m, "dev: %s\n", mei_dev_state_str(dev->dev_state));
+	seq_printf(m, "hbm: %s\n", mei_hbm_state_str(dev->hbm_state));
+
+	if (dev->hbm_state >= MEI_HBM_ENUM_CLIENTS &&
+	    dev->hbm_state <= MEI_HBM_STARTED) {
+		seq_puts(m, "hbm features:\n");
+		seq_printf(m, "\tPG: %01d\n", dev->hbm_f_pg_supported);
+		seq_printf(m, "\tDC: %01d\n", dev->hbm_f_dc_supported);
+		seq_printf(m, "\tIE: %01d\n", dev->hbm_f_ie_supported);
+		seq_printf(m, "\tDOT: %01d\n", dev->hbm_f_dot_supported);
+		seq_printf(m, "\tEV: %01d\n", dev->hbm_f_ev_supported);
+		seq_printf(m, "\tFA: %01d\n", dev->hbm_f_fa_supported);
+		seq_printf(m, "\tOS: %01d\n", dev->hbm_f_os_supported);
+		seq_printf(m, "\tDR: %01d\n", dev->hbm_f_dr_supported);
+		seq_printf(m, "\tVT: %01d\n", dev->hbm_f_vt_supported);
+		seq_printf(m, "\tCAP: %01d\n", dev->hbm_f_cap_supported);
+	}
+
+	seq_printf(m, "pg:  %s, %s\n",
+		   mei_pg_is_enabled(dev) ? "ENABLED" : "DISABLED",
+		   mei_pg_state_str(mei_pg_state(dev)));
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(mei_dbgfs_devstate);
+
+static ssize_t mei_dbgfs_write_allow_fa(struct file *file,
+					const char __user *user_buf,
+					size_t count, loff_t *ppos)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev = container_of(file->private_data,
+			   struct mei_device, allow_fixed_address);
+
+	ret = debugfs_write_file_bool(file, user_buf, count, ppos);
+	if (ret < 0)
+		return ret;
+	dev->override_fixed_address = true;
+	return ret;
+}
+
+static const struct file_operations mei_dbgfs_allow_fa_fops = {
+	.open = simple_open,
+	.read = debugfs_read_file_bool,
+	.write = mei_dbgfs_write_allow_fa,
+	.llseek = generic_file_llseek,
+};
+
+/**
+ * mei_dbgfs_deregister - Remove the debugfs files and directories
+ *
+ * @dev: the mei device structure
+ */
+void mei_dbgfs_deregister(struct mei_device *dev)
+{
+	if (!dev->dbgfs_dir)
+		return;
+	debugfs_remove_recursive(dev->dbgfs_dir);
+	dev->dbgfs_dir = NULL;
+}
+
+/**
+ * mei_dbgfs_register - Add the debugfs files
+ *
+ * @dev: the mei device structure
+ * @name: the mei device name
+ */
+void mei_dbgfs_register(struct mei_device *dev, const char *name)
+{
+	struct dentry *dir;
+
+	dir = debugfs_create_dir(name, NULL);
+	dev->dbgfs_dir = dir;
+
+	debugfs_create_file("meclients", S_IRUSR, dir, dev,
+			    &mei_dbgfs_meclients_fops);
+	debugfs_create_file("active", S_IRUSR, dir, dev,
+			    &mei_dbgfs_active_fops);
+	debugfs_create_file("devstate", S_IRUSR, dir, dev,
+			    &mei_dbgfs_devstate_fops);
+	debugfs_create_file("allow_fixed_address", S_IRUSR | S_IWUSR, dir,
+			    &dev->allow_fixed_address,
+			    &mei_dbgfs_allow_fa_fops);
+}
diff --git a/drivers/misc/mei/dma-ring.c b/drivers/misc/mei/dma-ring.c
new file mode 100644
index 000000000..ef56f849b
--- /dev/null
+++ b/drivers/misc/mei/dma-ring.c
@@ -0,0 +1,269 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(c) 2016-2018 Intel Corporation. All rights reserved.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+
+/**
+ * mei_dmam_dscr_alloc() - allocate a managed coherent buffer
+ *     for the dma descriptor
+ * @dev: mei_device
+ * @dscr: dma descriptor
+ *
+ * Return:
+ * * 0       - on success or zero allocation request
+ * * -EINVAL - if size is not power of 2
+ * * -ENOMEM - of allocation has failed
+ */
+static int mei_dmam_dscr_alloc(struct mei_device *dev,
+			       struct mei_dma_dscr *dscr)
+{
+	if (!dscr->size)
+		return 0;
+
+	if (WARN_ON(!is_power_of_2(dscr->size)))
+		return -EINVAL;
+
+	if (dscr->vaddr)
+		return 0;
+
+	dscr->vaddr = dmam_alloc_coherent(dev->dev, dscr->size, &dscr->daddr,
+					  GFP_KERNEL);
+	if (!dscr->vaddr)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/**
+ * mei_dmam_dscr_free() - free a managed coherent buffer
+ *     from the dma descriptor
+ * @dev: mei_device
+ * @dscr: dma descriptor
+ */
+static void mei_dmam_dscr_free(struct mei_device *dev,
+			       struct mei_dma_dscr *dscr)
+{
+	if (!dscr->vaddr)
+		return;
+
+	dmam_free_coherent(dev->dev, dscr->size, dscr->vaddr, dscr->daddr);
+	dscr->vaddr = NULL;
+}
+
+/**
+ * mei_dmam_ring_free() - free dma ring buffers
+ * @dev: mei device
+ */
+void mei_dmam_ring_free(struct mei_device *dev)
+{
+	int i;
+
+	for (i = 0; i < DMA_DSCR_NUM; i++)
+		mei_dmam_dscr_free(dev, &dev->dr_dscr[i]);
+}
+
+/**
+ * mei_dmam_ring_alloc() - allocate dma ring buffers
+ * @dev: mei device
+ *
+ * Return: -ENOMEM on allocation failure 0 otherwise
+ */
+int mei_dmam_ring_alloc(struct mei_device *dev)
+{
+	int i;
+
+	for (i = 0; i < DMA_DSCR_NUM; i++)
+		if (mei_dmam_dscr_alloc(dev, &dev->dr_dscr[i]))
+			goto err;
+
+	return 0;
+
+err:
+	mei_dmam_ring_free(dev);
+	return -ENOMEM;
+}
+
+/**
+ * mei_dma_ring_is_allocated() - check if dma ring is allocated
+ * @dev: mei device
+ *
+ * Return: true if dma ring is allocated
+ */
+bool mei_dma_ring_is_allocated(struct mei_device *dev)
+{
+	return !!dev->dr_dscr[DMA_DSCR_HOST].vaddr;
+}
+
+static inline
+struct hbm_dma_ring_ctrl *mei_dma_ring_ctrl(struct mei_device *dev)
+{
+	return (struct hbm_dma_ring_ctrl *)dev->dr_dscr[DMA_DSCR_CTRL].vaddr;
+}
+
+/**
+ * mei_dma_ring_reset() - reset the dma control block
+ * @dev: mei device
+ */
+void mei_dma_ring_reset(struct mei_device *dev)
+{
+	struct hbm_dma_ring_ctrl *ctrl = mei_dma_ring_ctrl(dev);
+
+	if (!ctrl)
+		return;
+
+	memset(ctrl, 0, sizeof(*ctrl));
+}
+
+/**
+ * mei_dma_copy_from() - copy from dma ring into buffer
+ * @dev: mei device
+ * @buf: data buffer
+ * @offset: offset in slots.
+ * @n: number of slots to copy.
+ */
+static size_t mei_dma_copy_from(struct mei_device *dev, unsigned char *buf,
+				u32 offset, u32 n)
+{
+	unsigned char *dbuf = dev->dr_dscr[DMA_DSCR_DEVICE].vaddr;
+
+	size_t b_offset = offset << 2;
+	size_t b_n = n << 2;
+
+	memcpy(buf, dbuf + b_offset, b_n);
+
+	return b_n;
+}
+
+/**
+ * mei_dma_copy_to() - copy to a buffer to the dma ring
+ * @dev: mei device
+ * @buf: data buffer
+ * @offset: offset in slots.
+ * @n: number of slots to copy.
+ */
+static size_t mei_dma_copy_to(struct mei_device *dev, unsigned char *buf,
+			      u32 offset, u32 n)
+{
+	unsigned char *hbuf = dev->dr_dscr[DMA_DSCR_HOST].vaddr;
+
+	size_t b_offset = offset << 2;
+	size_t b_n = n << 2;
+
+	memcpy(hbuf + b_offset, buf, b_n);
+
+	return b_n;
+}
+
+/**
+ * mei_dma_ring_read() - read data from the ring
+ * @dev: mei device
+ * @buf: buffer to read into: may be NULL in case of droping the data.
+ * @len: length to read.
+ */
+void mei_dma_ring_read(struct mei_device *dev, unsigned char *buf, u32 len)
+{
+	struct hbm_dma_ring_ctrl *ctrl = mei_dma_ring_ctrl(dev);
+	u32 dbuf_depth;
+	u32 rd_idx, rem, slots;
+
+	if (WARN_ON(!ctrl))
+		return;
+
+	dev_dbg(dev->dev, "reading from dma %u bytes\n", len);
+
+	if (!len)
+		return;
+
+	dbuf_depth = dev->dr_dscr[DMA_DSCR_DEVICE].size >> 2;
+	rd_idx = READ_ONCE(ctrl->dbuf_rd_idx) & (dbuf_depth - 1);
+	slots = mei_data2slots(len);
+
+	/* if buf is NULL we drop the packet by advancing the pointer.*/
+	if (!buf)
+		goto out;
+
+	if (rd_idx + slots > dbuf_depth) {
+		buf += mei_dma_copy_from(dev, buf, rd_idx, dbuf_depth - rd_idx);
+		rem = slots - (dbuf_depth - rd_idx);
+		rd_idx = 0;
+	} else {
+		rem = slots;
+	}
+
+	mei_dma_copy_from(dev, buf, rd_idx, rem);
+out:
+	WRITE_ONCE(ctrl->dbuf_rd_idx, ctrl->dbuf_rd_idx + slots);
+}
+
+static inline u32 mei_dma_ring_hbuf_depth(struct mei_device *dev)
+{
+	return dev->dr_dscr[DMA_DSCR_HOST].size >> 2;
+}
+
+/**
+ * mei_dma_ring_empty_slots() - calaculate number of empty slots in dma ring
+ * @dev: mei_device
+ *
+ * Return: number of empty slots
+ */
+u32 mei_dma_ring_empty_slots(struct mei_device *dev)
+{
+	struct hbm_dma_ring_ctrl *ctrl = mei_dma_ring_ctrl(dev);
+	u32 wr_idx, rd_idx, hbuf_depth, empty;
+
+	if (!mei_dma_ring_is_allocated(dev))
+		return 0;
+
+	if (WARN_ON(!ctrl))
+		return 0;
+
+	/* easier to work in slots */
+	hbuf_depth = mei_dma_ring_hbuf_depth(dev);
+	rd_idx = READ_ONCE(ctrl->hbuf_rd_idx);
+	wr_idx = READ_ONCE(ctrl->hbuf_wr_idx);
+
+	if (rd_idx > wr_idx)
+		empty = rd_idx - wr_idx;
+	else
+		empty = hbuf_depth - (wr_idx - rd_idx);
+
+	return empty;
+}
+
+/**
+ * mei_dma_ring_write - write data to dma ring host buffer
+ *
+ * @dev: mei_device
+ * @buf: data will be written
+ * @len: data length
+ */
+void mei_dma_ring_write(struct mei_device *dev, unsigned char *buf, u32 len)
+{
+	struct hbm_dma_ring_ctrl *ctrl = mei_dma_ring_ctrl(dev);
+	u32 hbuf_depth;
+	u32 wr_idx, rem, slots;
+
+	if (WARN_ON(!ctrl))
+		return;
+
+	dev_dbg(dev->dev, "writing to dma %u bytes\n", len);
+	hbuf_depth = mei_dma_ring_hbuf_depth(dev);
+	wr_idx = READ_ONCE(ctrl->hbuf_wr_idx) & (hbuf_depth - 1);
+	slots = mei_data2slots(len);
+
+	if (wr_idx + slots > hbuf_depth) {
+		buf += mei_dma_copy_to(dev, buf, wr_idx, hbuf_depth - wr_idx);
+		rem = slots - (hbuf_depth - wr_idx);
+		wr_idx = 0;
+	} else {
+		rem = slots;
+	}
+
+	mei_dma_copy_to(dev, buf, wr_idx, rem);
+
+	WRITE_ONCE(ctrl->hbuf_wr_idx, ctrl->hbuf_wr_idx + slots);
+}
diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
new file mode 100644
index 000000000..33579d979
--- /dev/null
+++ b/drivers/misc/mei/hbm.c
@@ -0,0 +1,1437 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+static const char *mei_hbm_status_str(enum mei_hbm_status status)
+{
+#define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
+	switch (status) {
+	MEI_HBM_STATUS(SUCCESS);
+	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
+	MEI_HBM_STATUS(ALREADY_EXISTS);
+	MEI_HBM_STATUS(REJECTED);
+	MEI_HBM_STATUS(INVALID_PARAMETER);
+	MEI_HBM_STATUS(NOT_ALLOWED);
+	MEI_HBM_STATUS(ALREADY_STARTED);
+	MEI_HBM_STATUS(NOT_STARTED);
+	default: return "unknown";
+	}
+#undef MEI_HBM_STATUS
+};
+
+static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
+{
+#define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
+	switch (status) {
+	MEI_CL_CS(SUCCESS);
+	MEI_CL_CS(NOT_FOUND);
+	MEI_CL_CS(ALREADY_STARTED);
+	MEI_CL_CS(OUT_OF_RESOURCES);
+	MEI_CL_CS(MESSAGE_SMALL);
+	MEI_CL_CS(NOT_ALLOWED);
+	default: return "unknown";
+	}
+#undef MEI_CL_CCS
+}
+
+const char *mei_hbm_state_str(enum mei_hbm_state state)
+{
+#define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
+	switch (state) {
+	MEI_HBM_STATE(IDLE);
+	MEI_HBM_STATE(STARTING);
+	MEI_HBM_STATE(STARTED);
+	MEI_HBM_STATE(DR_SETUP);
+	MEI_HBM_STATE(ENUM_CLIENTS);
+	MEI_HBM_STATE(CLIENT_PROPERTIES);
+	MEI_HBM_STATE(STOPPED);
+	default:
+		return "unknown";
+	}
+#undef MEI_HBM_STATE
+}
+
+/**
+ * mei_cl_conn_status_to_errno - convert client connect response
+ * status to error code
+ *
+ * @status: client connect response status
+ *
+ * Return: corresponding error code
+ */
+static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
+{
+	switch (status) {
+	case MEI_CL_CONN_SUCCESS:          return 0;
+	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
+	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
+	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
+	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
+	case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
+	default:                           return -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_write_message - wrapper for sending hbm messages.
+ *
+ * @dev: mei device
+ * @hdr: mei header
+ * @data: payload
+ */
+static inline int mei_hbm_write_message(struct mei_device *dev,
+					struct mei_msg_hdr *hdr,
+					const void *data)
+{
+	return mei_write_message(dev, hdr, sizeof(*hdr), data, hdr->length);
+}
+
+/**
+ * mei_hbm_idle - set hbm to idle state
+ *
+ * @dev: the device structure
+ */
+void mei_hbm_idle(struct mei_device *dev)
+{
+	dev->init_clients_timer = 0;
+	dev->hbm_state = MEI_HBM_IDLE;
+}
+
+/**
+ * mei_hbm_reset - reset hbm counters and book keeping data structurs
+ *
+ * @dev: the device structure
+ */
+void mei_hbm_reset(struct mei_device *dev)
+{
+	mei_me_cl_rm_all(dev);
+
+	mei_hbm_idle(dev);
+}
+
+/**
+ * mei_hbm_hdr - construct hbm header
+ *
+ * @mei_hdr: hbm header
+ * @length: payload length
+ */
+
+static inline void mei_hbm_hdr(struct mei_msg_hdr *mei_hdr, size_t length)
+{
+	memset(mei_hdr, 0, sizeof(*mei_hdr));
+	mei_hdr->length = length;
+	mei_hdr->msg_complete = 1;
+}
+
+/**
+ * mei_hbm_cl_hdr - construct client hbm header
+ *
+ * @cl: client
+ * @hbm_cmd: host bus message command
+ * @buf: buffer for cl header
+ * @len: buffer length
+ */
+static inline
+void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
+{
+	struct mei_hbm_cl_cmd *cmd = buf;
+
+	memset(cmd, 0, len);
+
+	cmd->hbm_cmd = hbm_cmd;
+	cmd->host_addr = mei_cl_host_addr(cl);
+	cmd->me_addr = mei_cl_me_id(cl);
+}
+
+/**
+ * mei_hbm_cl_write - write simple hbm client message
+ *
+ * @dev: the device structure
+ * @cl: client
+ * @hbm_cmd: host bus message command
+ * @buf: message buffer
+ * @len: buffer length
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static inline int mei_hbm_cl_write(struct mei_device *dev, struct mei_cl *cl,
+				   u8 hbm_cmd, void *buf, size_t len)
+{
+	struct mei_msg_hdr mei_hdr;
+
+	mei_hbm_hdr(&mei_hdr, len);
+	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
+
+	return mei_hbm_write_message(dev, &mei_hdr, buf);
+}
+
+/**
+ * mei_hbm_cl_addr_equal - check if the client's and
+ *	the message address match
+ *
+ * @cl: client
+ * @cmd: hbm client message
+ *
+ * Return: true if addresses are the same
+ */
+static inline
+bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
+{
+	return  mei_cl_host_addr(cl) == cmd->host_addr &&
+		mei_cl_me_id(cl) == cmd->me_addr;
+}
+
+/**
+ * mei_hbm_cl_find_by_cmd - find recipient client
+ *
+ * @dev: the device structure
+ * @buf: a buffer with hbm cl command
+ *
+ * Return: the recipient client or NULL if not found
+ */
+static inline
+struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
+{
+	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->file_list, link)
+		if (mei_hbm_cl_addr_equal(cl, cmd))
+			return cl;
+	return NULL;
+}
+
+
+/**
+ * mei_hbm_start_wait - wait for start response message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_start_wait(struct mei_device *dev)
+{
+	int ret;
+
+	if (dev->hbm_state > MEI_HBM_STARTING)
+		return 0;
+
+	mutex_unlock(&dev->device_lock);
+	ret = wait_event_timeout(dev->wait_hbm_start,
+			dev->hbm_state != MEI_HBM_STARTING,
+			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
+		dev->hbm_state = MEI_HBM_IDLE;
+		dev_err(dev->dev, "waiting for mei start failed\n");
+		return -ETIME;
+	}
+	return 0;
+}
+
+/**
+ * mei_hbm_start_req - sends start request message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_start_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_host_version_request req;
+	int ret;
+
+	mei_hbm_reset(dev);
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	/* host start message */
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_START_REQ_CMD;
+	req.host_version.major_version = HBM_MAJOR_VERSION;
+	req.host_version.minor_version = HBM_MINOR_VERSION;
+
+	dev->hbm_state = MEI_HBM_IDLE;
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "version message write failed: ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_STARTING;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_dma_setup_req() - setup DMA request
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_dma_setup_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_dma_setup_request req;
+	unsigned int i;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
+	for (i = 0; i < DMA_DSCR_NUM; i++) {
+		phys_addr_t paddr;
+
+		paddr = dev->dr_dscr[i].daddr;
+		req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
+		req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
+		req.dma_dscr[i].size = dev->dr_dscr[i].size;
+	}
+
+	mei_dma_ring_reset(dev);
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
+			ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_DR_SETUP;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_capabilities_req - request capabilities
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_capabilities_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_capability_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = MEI_HBM_CAPABILITIES_REQ_CMD;
+	if (dev->hbm_f_vt_supported)
+		req.capability_requested[0] = HBM_CAP_VT;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev,
+			"capabilities request write failed: ret = %d.\n", ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_CAP_SETUP;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_enum_clients_req - sends enumeration client request message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_enum_clients_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_host_enum_request req;
+	int ret;
+
+	/* enumerate clients */
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_ENUM_REQ_CMD;
+	req.flags |= dev->hbm_f_dc_supported ? MEI_HBM_ENUM_F_ALLOW_ADD : 0;
+	req.flags |= dev->hbm_f_ie_supported ?
+			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
+			ret);
+		return ret;
+	}
+	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_me_cl_add - add new me client to the list
+ *
+ * @dev: the device structure
+ * @res: hbm property response
+ *
+ * Return: 0 on success and -ENOMEM on allocation failure
+ */
+
+static int mei_hbm_me_cl_add(struct mei_device *dev,
+			     struct hbm_props_response *res)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *uuid = &res->client_properties.protocol_name;
+
+	mei_me_cl_rm_by_uuid(dev, uuid);
+
+	me_cl = kzalloc(sizeof(*me_cl), GFP_KERNEL);
+	if (!me_cl)
+		return -ENOMEM;
+
+	mei_me_cl_init(me_cl);
+
+	me_cl->props = res->client_properties;
+	me_cl->client_id = res->me_addr;
+	me_cl->tx_flow_ctrl_creds = 0;
+
+	mei_me_cl_add(dev, me_cl);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_add_cl_resp - send response to fw on client add request
+ *
+ * @dev: the device structure
+ * @addr: me address
+ * @status: response status
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_add_client_response resp;
+	int ret;
+
+	dev_dbg(dev->dev, "adding client response\n");
+
+	mei_hbm_hdr(&mei_hdr, sizeof(resp));
+
+	memset(&resp, 0, sizeof(resp));
+	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
+	resp.me_addr = addr;
+	resp.status  = status;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &resp);
+	if (ret)
+		dev_err(dev->dev, "add client response write failed: ret = %d\n",
+			ret);
+	return ret;
+}
+
+/**
+ * mei_hbm_fw_add_cl_req - request from the fw to add a client
+ *
+ * @dev: the device structure
+ * @req: add client request
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
+			      struct hbm_add_client_request *req)
+{
+	int ret;
+	u8 status = MEI_HBMS_SUCCESS;
+
+	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
+			sizeof(struct hbm_props_response));
+
+	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
+	if (ret)
+		status = !MEI_HBMS_SUCCESS;
+
+	if (dev->dev_state == MEI_DEV_ENABLED)
+		schedule_work(&dev->bus_rescan_work);
+
+	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
+}
+
+/**
+ * mei_hbm_cl_notify_req - send notification request
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ * @start: true for start false for stop
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_notify_req(struct mei_device *dev,
+			  struct mei_cl *cl, u8 start)
+{
+
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_notification_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, sizeof(req));
+
+	req.start = start;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+/**
+ *  notify_res_to_fop - convert notification response to the proper
+ *      notification FOP
+ *
+ * @cmd: client notification start response command
+ *
+ * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
+ */
+static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	return mei_cl_notify_req2fop(rs->start);
+}
+
+/**
+ * mei_hbm_cl_notify_start_res - update the client state according
+ *       notify start response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: client notification start response command
+ */
+static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
+					struct mei_cl *cl,
+					struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
+
+	if (rs->status == MEI_HBMS_SUCCESS ||
+	    rs->status == MEI_HBMS_ALREADY_STARTED) {
+		cl->notify_en = true;
+		cl->status = 0;
+	} else {
+		cl->status = -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_cl_notify_stop_res - update the client state according
+ *       notify stop response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: client notification stop response command
+ */
+static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
+				       struct mei_cl *cl,
+				       struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
+
+	if (rs->status == MEI_HBMS_SUCCESS ||
+	    rs->status == MEI_HBMS_NOT_STARTED) {
+		cl->notify_en = false;
+		cl->status = 0;
+	} else {
+		/* TODO: spec is not clear yet about other possible issues */
+		cl->status = -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_cl_notify - signal notification event
+ *
+ * @dev: the device structure
+ * @cmd: notification client message
+ */
+static void mei_hbm_cl_notify(struct mei_device *dev,
+			      struct mei_hbm_cl_cmd *cmd)
+{
+	struct mei_cl *cl;
+
+	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
+	if (cl)
+		mei_cl_notify(cl);
+}
+
+/**
+ * mei_hbm_prop_req - request property for a single client
+ *
+ * @dev: the device structure
+ * @start_idx: client index to start search
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_props_request req;
+	unsigned long addr;
+	int ret;
+
+	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
+
+	/* We got all client properties */
+	if (addr == MEI_CLIENTS_MAX) {
+		dev->hbm_state = MEI_HBM_STARTED;
+		mei_host_client_init(dev);
+		return 0;
+	}
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
+	req.me_addr = addr;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "properties request write failed: ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	mei_schedule_stall_timer(dev);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_pg - sends pg command
+ *
+ * @dev: the device structure
+ * @pg_cmd: the pg command code
+ *
+ * Return: -EIO on write failure
+ *         -EOPNOTSUPP if the operation is not supported by the protocol
+ */
+int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_power_gate req;
+	int ret;
+
+	if (!dev->hbm_f_pg_supported)
+		return -EOPNOTSUPP;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = pg_cmd;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "power gate command write failed.\n");
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_hbm_pg);
+
+/**
+ * mei_hbm_stop_req - send stop request message
+ *
+ * @dev: mei device
+ *
+ * Return: -EIO on write failure
+ */
+static int mei_hbm_stop_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_host_stop_request req;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_STOP_REQ_CMD;
+	req.reason = DRIVER_STOP_REQUEST;
+
+	return mei_hbm_write_message(dev, &mei_hdr, &req);
+}
+
+/**
+ * mei_hbm_cl_flow_control_req - sends flow control request.
+ *
+ * @dev: the device structure
+ * @cl: client info
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct hbm_flow_control req;
+
+	cl_dbg(dev, cl, "sending flow control\n");
+	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
+ *
+ * @dev: the device structure
+ * @fctrl: flow control response bus message
+ *
+ * Return: 0 on success, < 0 otherwise
+ */
+static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
+						 struct hbm_flow_control *fctrl)
+{
+	struct mei_me_client *me_cl;
+	int rets;
+
+	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
+	if (!me_cl) {
+		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
+		return -ENOENT;
+	}
+
+	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
+		rets = -EINVAL;
+		goto out;
+	}
+
+	me_cl->tx_flow_ctrl_creds++;
+	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
+		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
+
+	rets = 0;
+out:
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_hbm_cl_flow_control_res - flow control response from me
+ *
+ * @dev: the device structure
+ * @fctrl: flow control response bus message
+ */
+static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
+					       struct hbm_flow_control *fctrl)
+{
+	struct mei_cl *cl;
+
+	if (!fctrl->host_addr) {
+		/* single receive buffer */
+		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
+		return;
+	}
+
+	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
+	if (cl) {
+		cl->tx_flow_ctrl_creds++;
+		cl_dbg(dev, cl, "flow control creds = %d.\n",
+				cl->tx_flow_ctrl_creds);
+	}
+}
+
+
+/**
+ * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct hbm_client_connect_request req;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct hbm_client_connect_response resp;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
+				&resp, sizeof(resp));
+}
+
+/**
+ * mei_hbm_cl_disconnect_res - update the client state according
+ *       disconnect response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: disconnect client response host bus message
+ */
+static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
+				      struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_client_connect_response *rs =
+		(struct hbm_client_connect_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
+
+	if (rs->status == MEI_CL_DISCONN_SUCCESS)
+		cl->state = MEI_FILE_DISCONNECT_REPLY;
+	cl->status = 0;
+}
+
+/**
+ * mei_hbm_cl_connect_req - send connection request to specific me client
+ *
+ * @dev: the device structure
+ * @cl: a client to connect to
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct hbm_client_connect_request req;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * mei_hbm_cl_connect_res - update the client state according
+ *        connection response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: connect client response host bus message
+ */
+static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
+				   struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_client_connect_response *rs =
+		(struct hbm_client_connect_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
+			mei_cl_conn_status_str(rs->status));
+
+	if (rs->status == MEI_CL_CONN_SUCCESS)
+		cl->state = MEI_FILE_CONNECTED;
+	else {
+		cl->state = MEI_FILE_DISCONNECT_REPLY;
+		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
+			mei_me_cl_del(dev, cl->me_cl);
+			if (dev->dev_state == MEI_DEV_ENABLED)
+				schedule_work(&dev->bus_rescan_work);
+		}
+	}
+	cl->status = mei_cl_conn_status_to_errno(rs->status);
+}
+
+/**
+ * mei_hbm_cl_res - process hbm response received on behalf
+ *         an client
+ *
+ * @dev: the device structure
+ * @rs:  hbm client message
+ * @fop_type: file operation type
+ */
+static void mei_hbm_cl_res(struct mei_device *dev,
+			   struct mei_hbm_cl_cmd *rs,
+			   enum mei_cb_file_ops fop_type)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
+
+		cl = cb->cl;
+
+		if (cb->fop_type != fop_type)
+			continue;
+
+		if (mei_hbm_cl_addr_equal(cl, rs)) {
+			list_del_init(&cb->list);
+			break;
+		}
+	}
+
+	if (!cl)
+		return;
+
+	switch (fop_type) {
+	case MEI_FOP_CONNECT:
+		mei_hbm_cl_connect_res(dev, cl, rs);
+		break;
+	case MEI_FOP_DISCONNECT:
+		mei_hbm_cl_disconnect_res(dev, cl, rs);
+		break;
+	case MEI_FOP_NOTIFY_START:
+		mei_hbm_cl_notify_start_res(dev, cl, rs);
+		break;
+	case MEI_FOP_NOTIFY_STOP:
+		mei_hbm_cl_notify_stop_res(dev, cl, rs);
+		break;
+	default:
+		return;
+	}
+
+	cl->timer_count = 0;
+	wake_up(&cl->wait);
+}
+
+
+/**
+ * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
+ *  host sends disconnect response
+ *
+ * @dev: the device structure.
+ * @disconnect_req: disconnect request bus message from the me
+ *
+ * Return: -ENOMEM on allocation failure
+ */
+static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
+		struct hbm_client_connect_request *disconnect_req)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb;
+
+	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
+	if (cl) {
+		cl_warn(dev, cl, "fw disconnect request received\n");
+		cl->state = MEI_FILE_DISCONNECTING;
+		cl->timer_count = 0;
+
+		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
+					       NULL);
+		if (!cb)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+/**
+ * mei_hbm_pg_enter_res - PG enter response received
+ *
+ * @dev: the device structure.
+ *
+ * Return: 0 on success, -EPROTO on state mismatch
+ */
+static int mei_hbm_pg_enter_res(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) != MEI_PG_OFF ||
+	    dev->pg_event != MEI_PG_EVENT_WAIT) {
+		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
+			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
+		return -EPROTO;
+	}
+
+	dev->pg_event = MEI_PG_EVENT_RECEIVED;
+	wake_up(&dev->wait_pg);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_pg_resume - process with PG resume
+ *
+ * @dev: the device structure.
+ */
+void mei_hbm_pg_resume(struct mei_device *dev)
+{
+	pm_request_resume(dev->dev);
+}
+EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
+
+/**
+ * mei_hbm_pg_exit_res - PG exit response received
+ *
+ * @dev: the device structure.
+ *
+ * Return: 0 on success, -EPROTO on state mismatch
+ */
+static int mei_hbm_pg_exit_res(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) != MEI_PG_ON ||
+	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
+	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
+		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
+			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
+		return -EPROTO;
+	}
+
+	switch (dev->pg_event) {
+	case MEI_PG_EVENT_WAIT:
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		wake_up(&dev->wait_pg);
+		break;
+	case MEI_PG_EVENT_IDLE:
+		/*
+		* If the driver is not waiting on this then
+		* this is HW initiated exit from PG.
+		* Start runtime pm resume sequence to exit from PG.
+		*/
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		mei_hbm_pg_resume(dev);
+		break;
+	default:
+		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
+		     dev->pg_event);
+		return -EPROTO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hbm_config_features - check what hbm features and commands
+ *        are supported by the fw
+ *
+ * @dev: the device structure
+ */
+static void mei_hbm_config_features(struct mei_device *dev)
+{
+	/* Power Gating Isolation Support */
+	dev->hbm_f_pg_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
+		dev->hbm_f_pg_supported = 1;
+
+	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
+	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
+		dev->hbm_f_pg_supported = 1;
+
+	dev->hbm_f_dc_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
+		dev->hbm_f_dc_supported = 1;
+
+	dev->hbm_f_ie_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
+		dev->hbm_f_ie_supported = 1;
+
+	/* disconnect on connect timeout instead of link reset */
+	dev->hbm_f_dot_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
+		dev->hbm_f_dot_supported = 1;
+
+	/* Notification Event Support */
+	dev->hbm_f_ev_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
+		dev->hbm_f_ev_supported = 1;
+
+	/* Fixed Address Client Support */
+	dev->hbm_f_fa_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
+		dev->hbm_f_fa_supported = 1;
+
+	/* OS ver message Support */
+	dev->hbm_f_os_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
+		dev->hbm_f_os_supported = 1;
+
+	/* DMA Ring Support */
+	dev->hbm_f_dr_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_DR ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_DR &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_DR))
+		dev->hbm_f_dr_supported = 1;
+
+	/* VTag Support */
+	dev->hbm_f_vt_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_VT ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_VT &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_VT))
+		dev->hbm_f_vt_supported = 1;
+
+	/* Capability message Support */
+	dev->hbm_f_cap_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_CAP ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_CAP &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_CAP))
+		dev->hbm_f_cap_supported = 1;
+}
+
+/**
+ * mei_hbm_version_is_supported - checks whether the driver can
+ *     support the hbm version of the device
+ *
+ * @dev: the device structure
+ * Return: true if driver can support hbm version of the device
+ */
+bool mei_hbm_version_is_supported(struct mei_device *dev)
+{
+	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
+		(dev->version.major_version == HBM_MAJOR_VERSION &&
+		 dev->version.minor_version <= HBM_MINOR_VERSION);
+}
+
+/**
+ * mei_hbm_dispatch - bottom half read routine after ISR to
+ * handle the read bus message cmd processing.
+ *
+ * @dev: the device structure
+ * @hdr: header of bus message
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
+{
+	struct mei_bus_message *mei_msg;
+	struct hbm_host_version_response *version_res;
+	struct hbm_props_response *props_res;
+	struct hbm_host_enum_response *enum_res;
+	struct hbm_dma_setup_response *dma_setup_res;
+	struct hbm_add_client_request *add_cl_req;
+	struct hbm_capability_response *capability_res;
+	int ret;
+
+	struct mei_hbm_cl_cmd *cl_cmd;
+	struct hbm_client_connect_request *disconnect_req;
+	struct hbm_flow_control *fctrl;
+
+	/* read the message to our buffer */
+	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
+	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
+	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
+	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
+
+	/* ignore spurious message and prevent reset nesting
+	 * hbm is put to idle during system reset
+	 */
+	if (dev->hbm_state == MEI_HBM_IDLE) {
+		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
+		return 0;
+	}
+
+	switch (mei_msg->hbm_cmd) {
+	case HOST_START_RES_CMD:
+		dev_dbg(dev->dev, "hbm: start: response message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		version_res = (struct hbm_host_version_response *)mei_msg;
+
+		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
+				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
+				version_res->me_max_version.major_version,
+				version_res->me_max_version.minor_version);
+
+		if (version_res->host_version_supported) {
+			dev->version.major_version = HBM_MAJOR_VERSION;
+			dev->version.minor_version = HBM_MINOR_VERSION;
+		} else {
+			dev->version.major_version =
+				version_res->me_max_version.major_version;
+			dev->version.minor_version =
+				version_res->me_max_version.minor_version;
+		}
+
+		if (!mei_hbm_version_is_supported(dev)) {
+			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
+
+			dev->hbm_state = MEI_HBM_STOPPED;
+			if (mei_hbm_stop_req(dev)) {
+				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
+				return -EIO;
+			}
+			break;
+		}
+
+		mei_hbm_config_features(dev);
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_STARTING) {
+			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		if (dev->hbm_f_cap_supported) {
+			if (mei_hbm_capabilities_req(dev))
+				return -EIO;
+			wake_up(&dev->wait_hbm_start);
+			break;
+		}
+
+		if (dev->hbm_f_dr_supported) {
+			if (mei_dmam_ring_alloc(dev))
+				dev_info(dev->dev, "running w/o dma ring\n");
+			if (mei_dma_ring_is_allocated(dev)) {
+				if (mei_hbm_dma_setup_req(dev))
+					return -EIO;
+
+				wake_up(&dev->wait_hbm_start);
+				break;
+			}
+		}
+
+		dev->hbm_f_dr_supported = 0;
+		mei_dmam_ring_free(dev);
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+
+		wake_up(&dev->wait_hbm_start);
+		break;
+
+	case MEI_HBM_CAPABILITIES_RES_CMD:
+		dev_dbg(dev->dev, "hbm: capabilities response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->hbm_state != MEI_HBM_CAP_SETUP) {
+			dev_err(dev->dev, "hbm: capabilities response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		capability_res = (struct hbm_capability_response *)mei_msg;
+		if (!(capability_res->capability_granted[0] & HBM_CAP_VT))
+			dev->hbm_f_vt_supported = 0;
+
+		if (dev->hbm_f_dr_supported) {
+			if (mei_dmam_ring_alloc(dev))
+				dev_info(dev->dev, "running w/o dma ring\n");
+			if (mei_dma_ring_is_allocated(dev)) {
+				if (mei_hbm_dma_setup_req(dev))
+					return -EIO;
+				break;
+			}
+		}
+
+		dev->hbm_f_dr_supported = 0;
+		mei_dmam_ring_free(dev);
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+		break;
+
+	case MEI_HBM_DMA_SETUP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->hbm_state != MEI_HBM_DR_SETUP) {
+			dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
+
+		if (dma_setup_res->status) {
+			u8 status = dma_setup_res->status;
+
+			if (status == MEI_HBMS_NOT_ALLOWED) {
+				dev_dbg(dev->dev, "hbm: dma setup not allowed\n");
+			} else {
+				dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
+					 status,
+					 mei_hbm_status_str(status));
+			}
+			dev->hbm_f_dr_supported = 0;
+			mei_dmam_ring_free(dev);
+		}
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+		break;
+
+	case CLIENT_CONNECT_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
+		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
+		break;
+
+	case CLIENT_DISCONNECT_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
+		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
+		break;
+
+	case MEI_FLOW_CONTROL_CMD:
+		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
+
+		fctrl = (struct hbm_flow_control *)mei_msg;
+		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
+		break;
+
+	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
+		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
+		ret = mei_hbm_pg_enter_res(dev);
+		if (ret)
+			return ret;
+		break;
+
+	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
+		ret = mei_hbm_pg_exit_res(dev);
+		if (ret)
+			return ret;
+		break;
+
+	case HOST_CLIENT_PROPERTIES_RES_CMD:
+		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
+			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		props_res = (struct hbm_props_response *)mei_msg;
+
+		if (props_res->status == MEI_HBMS_CLIENT_NOT_FOUND) {
+			dev_dbg(dev->dev, "hbm: properties response: %d CLIENT_NOT_FOUND\n",
+				props_res->me_addr);
+		} else if (props_res->status) {
+			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
+				props_res->status,
+				mei_hbm_status_str(props_res->status));
+			return -EPROTO;
+		} else {
+			mei_hbm_me_cl_add(dev, props_res);
+		}
+
+		/* request property for the next client */
+		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
+			return -EIO;
+
+		break;
+
+	case HOST_ENUM_RES_CMD:
+		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
+
+		dev->init_clients_timer = 0;
+
+		enum_res = (struct hbm_host_enum_response *) mei_msg;
+		BUILD_BUG_ON(sizeof(dev->me_clients_map)
+				< sizeof(enum_res->valid_addresses));
+		memcpy(dev->me_clients_map, enum_res->valid_addresses,
+				sizeof(enum_res->valid_addresses));
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
+			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
+
+		/* first property request */
+		if (mei_hbm_prop_req(dev, 0))
+			return -EIO;
+
+		break;
+
+	case HOST_STOP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: stop response: message received\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->hbm_state != MEI_HBM_STOPPED) {
+			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
+		dev_info(dev->dev, "hbm: stop response: resetting.\n");
+		/* force the reset */
+		return -EPROTO;
+		break;
+
+	case CLIENT_DISCONNECT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
+
+		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
+		mei_hbm_fw_disconnect_req(dev, disconnect_req);
+		break;
+
+	case ME_STOP_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: stop request: message received\n");
+		dev->hbm_state = MEI_HBM_STOPPED;
+		if (mei_hbm_stop_req(dev)) {
+			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
+			return -EIO;
+		}
+		break;
+
+	case MEI_HBM_ADD_CLIENT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: add client request received\n");
+		/*
+		 * after the host receives the enum_resp
+		 * message clients may be added or removed
+		 */
+		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
+		    dev->hbm_state >= MEI_HBM_STOPPED) {
+			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+		add_cl_req = (struct hbm_add_client_request *)mei_msg;
+		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
+		if (ret) {
+			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
+				ret);
+			return -EIO;
+		}
+		dev_dbg(dev->dev, "hbm: add client request processed\n");
+		break;
+
+	case MEI_HBM_NOTIFY_RES_CMD:
+		dev_dbg(dev->dev, "hbm: notify response received\n");
+		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
+		break;
+
+	case MEI_HBM_NOTIFICATION_CMD:
+		dev_dbg(dev->dev, "hbm: notification\n");
+		mei_hbm_cl_notify(dev, cl_cmd);
+		break;
+
+	default:
+		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
+		return -EPROTO;
+
+	}
+	return 0;
+}
+
diff --git a/drivers/misc/mei/hbm.h b/drivers/misc/mei/hbm.h
new file mode 100644
index 000000000..4d95e38e4
--- /dev/null
+++ b/drivers/misc/mei/hbm.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_HBM_H_
+#define _MEI_HBM_H_
+
+struct mei_device;
+struct mei_msg_hdr;
+struct mei_cl;
+
+/**
+ * enum mei_hbm_state - host bus message protocol state
+ *
+ * @MEI_HBM_IDLE : protocol not started
+ * @MEI_HBM_STARTING : start request message was sent
+ * @MEI_HBM_CAP_SETUP : capabilities request message was sent
+ * @MEI_HBM_DR_SETUP : dma ring setup request message was sent
+ * @MEI_HBM_ENUM_CLIENTS : enumeration request was sent
+ * @MEI_HBM_CLIENT_PROPERTIES : acquiring clients properties
+ * @MEI_HBM_STARTED : enumeration was completed
+ * @MEI_HBM_STOPPED : stopping exchange
+ */
+enum mei_hbm_state {
+	MEI_HBM_IDLE = 0,
+	MEI_HBM_STARTING,
+	MEI_HBM_CAP_SETUP,
+	MEI_HBM_DR_SETUP,
+	MEI_HBM_ENUM_CLIENTS,
+	MEI_HBM_CLIENT_PROPERTIES,
+	MEI_HBM_STARTED,
+	MEI_HBM_STOPPED,
+};
+
+const char *mei_hbm_state_str(enum mei_hbm_state state);
+
+int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr);
+
+void mei_hbm_idle(struct mei_device *dev);
+void mei_hbm_reset(struct mei_device *dev);
+int mei_hbm_start_req(struct mei_device *dev);
+int mei_hbm_start_wait(struct mei_device *dev);
+int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl);
+int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl);
+int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl);
+int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl);
+bool mei_hbm_version_is_supported(struct mei_device *dev);
+int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd);
+void mei_hbm_pg_resume(struct mei_device *dev);
+int mei_hbm_cl_notify_req(struct mei_device *dev,
+			  struct mei_cl *cl, u8 request);
+
+#endif /* _MEI_HBM_H_ */
+
diff --git a/drivers/misc/mei/hdcp/Kconfig b/drivers/misc/mei/hdcp/Kconfig
new file mode 100644
index 000000000..95b2d6d37
--- /dev/null
+++ b/drivers/misc/mei/hdcp/Kconfig
@@ -0,0 +1,13 @@
+
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2019, Intel Corporation. All rights reserved.
+#
+config INTEL_MEI_HDCP
+	tristate "Intel HDCP2.2 services of ME Interface"
+	select INTEL_MEI_ME
+	depends on DRM_I915
+	help
+	  MEI Support for HDCP2.2 Services on Intel platforms.
+
+	  Enables the ME FW services required for HDCP2.2 support through
+	  I915 display driver of Intel.
diff --git a/drivers/misc/mei/hdcp/Makefile b/drivers/misc/mei/hdcp/Makefile
new file mode 100644
index 000000000..3fbb56485
--- /dev/null
+++ b/drivers/misc/mei/hdcp/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) 2019, Intel Corporation. All rights reserved.
+#
+# Makefile - HDCP client driver for Intel MEI Bus Driver.
+
+obj-$(CONFIG_INTEL_MEI_HDCP) += mei_hdcp.o
diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
new file mode 100644
index 000000000..9ae9669e4
--- /dev/null
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -0,0 +1,880 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright © 2019 Intel Corporation
+ *
+ * mei_hdcp.c: HDCP client driver for mei bus
+ *
+ * Author:
+ * Ramalingam C <ramalingam.c@intel.com>
+ */
+
+/**
+ * DOC: MEI_HDCP Client Driver
+ *
+ * The mei_hdcp driver acts as a translation layer between HDCP 2.2
+ * protocol  implementer (I915) and ME FW by translating HDCP2.2
+ * negotiation messages to ME FW command payloads and vice versa.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/mei_cl_bus.h>
+#include <linux/component.h>
+#include <drm/drm_connector.h>
+#include <drm/i915_component.h>
+#include <drm/i915_mei_hdcp_interface.h>
+
+#include "mei_hdcp.h"
+
+/**
+ * mei_hdcp_initiate_session() - Initiate a Wired HDCP2.2 Tx Session in ME FW
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @ake_data: AKE_Init msg output.
+ *
+ * Return:  0 on Success, <0 on Failure.
+ */
+static int
+mei_hdcp_initiate_session(struct device *dev, struct hdcp_port_data *data,
+			  struct hdcp2_ake_init *ake_data)
+{
+	struct wired_cmd_initiate_hdcp2_session_in session_init_in = { { 0 } };
+	struct wired_cmd_initiate_hdcp2_session_out
+						session_init_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !ake_data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	session_init_in.header.api_version = HDCP_API_VERSION;
+	session_init_in.header.command_id = WIRED_INITIATE_HDCP2_SESSION;
+	session_init_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	session_init_in.header.buffer_len =
+				WIRED_CMD_BUF_LEN_INITIATE_HDCP2_SESSION_IN;
+
+	session_init_in.port.integrated_port_type = data->port_type;
+	session_init_in.port.physical_port = (u8)data->fw_ddi;
+	session_init_in.port.attached_transcoder = (u8)data->fw_tc;
+	session_init_in.protocol = data->protocol;
+
+	byte = mei_cldev_send(cldev, (u8 *)&session_init_in,
+			      sizeof(session_init_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&session_init_out,
+			      sizeof(session_init_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (session_init_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
+			WIRED_INITIATE_HDCP2_SESSION,
+			session_init_out.header.status);
+		return -EIO;
+	}
+
+	ake_data->msg_id = HDCP_2_2_AKE_INIT;
+	ake_data->tx_caps = session_init_out.tx_caps;
+	memcpy(ake_data->r_tx, session_init_out.r_tx, HDCP_2_2_RTX_LEN);
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_verify_receiver_cert_prepare_km() - Verify the Receiver Certificate
+ * AKE_Send_Cert and prepare AKE_Stored_Km/AKE_No_Stored_Km
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @rx_cert: AKE_Send_Cert for verification
+ * @km_stored: Pairing status flag output
+ * @ek_pub_km: AKE_Stored_Km/AKE_No_Stored_Km output msg
+ * @msg_sz : size of AKE_XXXXX_Km output msg
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_verify_receiver_cert_prepare_km(struct device *dev,
+					 struct hdcp_port_data *data,
+					 struct hdcp2_ake_send_cert *rx_cert,
+					 bool *km_stored,
+					 struct hdcp2_ake_no_stored_km
+								*ek_pub_km,
+					 size_t *msg_sz)
+{
+	struct wired_cmd_verify_receiver_cert_in verify_rxcert_in = { { 0 } };
+	struct wired_cmd_verify_receiver_cert_out verify_rxcert_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	verify_rxcert_in.header.api_version = HDCP_API_VERSION;
+	verify_rxcert_in.header.command_id = WIRED_VERIFY_RECEIVER_CERT;
+	verify_rxcert_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_rxcert_in.header.buffer_len =
+				WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_IN;
+
+	verify_rxcert_in.port.integrated_port_type = data->port_type;
+	verify_rxcert_in.port.physical_port = (u8)data->fw_ddi;
+	verify_rxcert_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	verify_rxcert_in.cert_rx = rx_cert->cert_rx;
+	memcpy(verify_rxcert_in.r_rx, &rx_cert->r_rx, HDCP_2_2_RRX_LEN);
+	memcpy(verify_rxcert_in.rx_caps, rx_cert->rx_caps, HDCP_2_2_RXCAPS_LEN);
+
+	byte = mei_cldev_send(cldev, (u8 *)&verify_rxcert_in,
+			      sizeof(verify_rxcert_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed: %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_rxcert_out,
+			      sizeof(verify_rxcert_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed: %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_rxcert_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
+			WIRED_VERIFY_RECEIVER_CERT,
+			verify_rxcert_out.header.status);
+		return -EIO;
+	}
+
+	*km_stored = !!verify_rxcert_out.km_stored;
+	if (verify_rxcert_out.km_stored) {
+		ek_pub_km->msg_id = HDCP_2_2_AKE_STORED_KM;
+		*msg_sz = sizeof(struct hdcp2_ake_stored_km);
+	} else {
+		ek_pub_km->msg_id = HDCP_2_2_AKE_NO_STORED_KM;
+		*msg_sz = sizeof(struct hdcp2_ake_no_stored_km);
+	}
+
+	memcpy(ek_pub_km->e_kpub_km, &verify_rxcert_out.ekm_buff,
+	       sizeof(verify_rxcert_out.ekm_buff));
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_verify_hprime() - Verify AKE_Send_H_prime at ME FW.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @rx_hprime: AKE_Send_H_prime msg for ME FW verification
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_verify_hprime(struct device *dev, struct hdcp_port_data *data,
+		       struct hdcp2_ake_send_hprime *rx_hprime)
+{
+	struct wired_cmd_ake_send_hprime_in send_hprime_in = { { 0 } };
+	struct wired_cmd_ake_send_hprime_out send_hprime_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !rx_hprime)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	send_hprime_in.header.api_version = HDCP_API_VERSION;
+	send_hprime_in.header.command_id = WIRED_AKE_SEND_HPRIME;
+	send_hprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	send_hprime_in.header.buffer_len = WIRED_CMD_BUF_LEN_AKE_SEND_HPRIME_IN;
+
+	send_hprime_in.port.integrated_port_type = data->port_type;
+	send_hprime_in.port.physical_port = (u8)data->fw_ddi;
+	send_hprime_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	memcpy(send_hprime_in.h_prime, rx_hprime->h_prime,
+	       HDCP_2_2_H_PRIME_LEN);
+
+	byte = mei_cldev_send(cldev, (u8 *)&send_hprime_in,
+			      sizeof(send_hprime_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&send_hprime_out,
+			      sizeof(send_hprime_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (send_hprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
+			WIRED_AKE_SEND_HPRIME, send_hprime_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_store_pairing_info() - Store pairing info received at ME FW
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @pairing_info: AKE_Send_Pairing_Info msg input to ME FW
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_store_pairing_info(struct device *dev, struct hdcp_port_data *data,
+			    struct hdcp2_ake_send_pairing_info *pairing_info)
+{
+	struct wired_cmd_ake_send_pairing_info_in pairing_info_in = { { 0 } };
+	struct wired_cmd_ake_send_pairing_info_out pairing_info_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !pairing_info)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	pairing_info_in.header.api_version = HDCP_API_VERSION;
+	pairing_info_in.header.command_id = WIRED_AKE_SEND_PAIRING_INFO;
+	pairing_info_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	pairing_info_in.header.buffer_len =
+					WIRED_CMD_BUF_LEN_SEND_PAIRING_INFO_IN;
+
+	pairing_info_in.port.integrated_port_type = data->port_type;
+	pairing_info_in.port.physical_port = (u8)data->fw_ddi;
+	pairing_info_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	memcpy(pairing_info_in.e_kh_km, pairing_info->e_kh_km,
+	       HDCP_2_2_E_KH_KM_LEN);
+
+	byte = mei_cldev_send(cldev, (u8 *)&pairing_info_in,
+			      sizeof(pairing_info_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&pairing_info_out,
+			      sizeof(pairing_info_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (pairing_info_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. Status: 0x%X\n",
+			WIRED_AKE_SEND_PAIRING_INFO,
+			pairing_info_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_initiate_locality_check() - Prepare LC_Init
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @lc_init_data: LC_Init msg output
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_initiate_locality_check(struct device *dev,
+				 struct hdcp_port_data *data,
+				 struct hdcp2_lc_init *lc_init_data)
+{
+	struct wired_cmd_init_locality_check_in lc_init_in = { { 0 } };
+	struct wired_cmd_init_locality_check_out lc_init_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !lc_init_data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	lc_init_in.header.api_version = HDCP_API_VERSION;
+	lc_init_in.header.command_id = WIRED_INIT_LOCALITY_CHECK;
+	lc_init_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	lc_init_in.header.buffer_len = WIRED_CMD_BUF_LEN_INIT_LOCALITY_CHECK_IN;
+
+	lc_init_in.port.integrated_port_type = data->port_type;
+	lc_init_in.port.physical_port = (u8)data->fw_ddi;
+	lc_init_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	byte = mei_cldev_send(cldev, (u8 *)&lc_init_in, sizeof(lc_init_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&lc_init_out, sizeof(lc_init_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (lc_init_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. status: 0x%X\n",
+			WIRED_INIT_LOCALITY_CHECK, lc_init_out.header.status);
+		return -EIO;
+	}
+
+	lc_init_data->msg_id = HDCP_2_2_LC_INIT;
+	memcpy(lc_init_data->r_n, lc_init_out.r_n, HDCP_2_2_RN_LEN);
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_verify_lprime() - Verify lprime.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @rx_lprime: LC_Send_L_prime msg for ME FW verification
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_verify_lprime(struct device *dev, struct hdcp_port_data *data,
+		       struct hdcp2_lc_send_lprime *rx_lprime)
+{
+	struct wired_cmd_validate_locality_in verify_lprime_in = { { 0 } };
+	struct wired_cmd_validate_locality_out verify_lprime_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !rx_lprime)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	verify_lprime_in.header.api_version = HDCP_API_VERSION;
+	verify_lprime_in.header.command_id = WIRED_VALIDATE_LOCALITY;
+	verify_lprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_lprime_in.header.buffer_len =
+					WIRED_CMD_BUF_LEN_VALIDATE_LOCALITY_IN;
+
+	verify_lprime_in.port.integrated_port_type = data->port_type;
+	verify_lprime_in.port.physical_port = (u8)data->fw_ddi;
+	verify_lprime_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	memcpy(verify_lprime_in.l_prime, rx_lprime->l_prime,
+	       HDCP_2_2_L_PRIME_LEN);
+
+	byte = mei_cldev_send(cldev, (u8 *)&verify_lprime_in,
+			      sizeof(verify_lprime_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_lprime_out,
+			      sizeof(verify_lprime_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_lprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_VALIDATE_LOCALITY,
+			verify_lprime_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_get_session_key() - Prepare SKE_Send_Eks.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @ske_data: SKE_Send_Eks msg output from ME FW.
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int mei_hdcp_get_session_key(struct device *dev,
+				    struct hdcp_port_data *data,
+				    struct hdcp2_ske_send_eks *ske_data)
+{
+	struct wired_cmd_get_session_key_in get_skey_in = { { 0 } };
+	struct wired_cmd_get_session_key_out get_skey_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data || !ske_data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	get_skey_in.header.api_version = HDCP_API_VERSION;
+	get_skey_in.header.command_id = WIRED_GET_SESSION_KEY;
+	get_skey_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	get_skey_in.header.buffer_len = WIRED_CMD_BUF_LEN_GET_SESSION_KEY_IN;
+
+	get_skey_in.port.integrated_port_type = data->port_type;
+	get_skey_in.port.physical_port = (u8)data->fw_ddi;
+	get_skey_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	byte = mei_cldev_send(cldev, (u8 *)&get_skey_in, sizeof(get_skey_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&get_skey_out, sizeof(get_skey_out));
+
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (get_skey_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_GET_SESSION_KEY, get_skey_out.header.status);
+		return -EIO;
+	}
+
+	ske_data->msg_id = HDCP_2_2_SKE_SEND_EKS;
+	memcpy(ske_data->e_dkey_ks, get_skey_out.e_dkey_ks,
+	       HDCP_2_2_E_DKEY_KS_LEN);
+	memcpy(ske_data->riv, get_skey_out.r_iv, HDCP_2_2_RIV_LEN);
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_repeater_check_flow_prepare_ack() - Validate the Downstream topology
+ * and prepare rep_ack.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @rep_topology: Receiver ID List to be validated
+ * @rep_send_ack : repeater ack from ME FW.
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_repeater_check_flow_prepare_ack(struct device *dev,
+					 struct hdcp_port_data *data,
+					 struct hdcp2_rep_send_receiverid_list
+							*rep_topology,
+					 struct hdcp2_rep_send_ack
+							*rep_send_ack)
+{
+	struct wired_cmd_verify_repeater_in verify_repeater_in = { { 0 } };
+	struct wired_cmd_verify_repeater_out verify_repeater_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !rep_topology || !rep_send_ack || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	verify_repeater_in.header.api_version = HDCP_API_VERSION;
+	verify_repeater_in.header.command_id = WIRED_VERIFY_REPEATER;
+	verify_repeater_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_repeater_in.header.buffer_len =
+					WIRED_CMD_BUF_LEN_VERIFY_REPEATER_IN;
+
+	verify_repeater_in.port.integrated_port_type = data->port_type;
+	verify_repeater_in.port.physical_port = (u8)data->fw_ddi;
+	verify_repeater_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	memcpy(verify_repeater_in.rx_info, rep_topology->rx_info,
+	       HDCP_2_2_RXINFO_LEN);
+	memcpy(verify_repeater_in.seq_num_v, rep_topology->seq_num_v,
+	       HDCP_2_2_SEQ_NUM_LEN);
+	memcpy(verify_repeater_in.v_prime, rep_topology->v_prime,
+	       HDCP_2_2_V_PRIME_HALF_LEN);
+	memcpy(verify_repeater_in.receiver_ids, rep_topology->receiver_ids,
+	       HDCP_2_2_RECEIVER_IDS_MAX_LEN);
+
+	byte = mei_cldev_send(cldev, (u8 *)&verify_repeater_in,
+			      sizeof(verify_repeater_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_repeater_out,
+			      sizeof(verify_repeater_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_repeater_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_VERIFY_REPEATER,
+			verify_repeater_out.header.status);
+		return -EIO;
+	}
+
+	memcpy(rep_send_ack->v, verify_repeater_out.v,
+	       HDCP_2_2_V_PRIME_HALF_LEN);
+	rep_send_ack->msg_id = HDCP_2_2_REP_SEND_ACK;
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_verify_mprime() - Verify mprime.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ * @stream_ready: RepeaterAuth_Stream_Ready msg for ME FW verification.
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int mei_hdcp_verify_mprime(struct device *dev,
+				  struct hdcp_port_data *data,
+				  struct hdcp2_rep_stream_ready *stream_ready)
+{
+	struct wired_cmd_repeater_auth_stream_req_in *verify_mprime_in;
+	struct wired_cmd_repeater_auth_stream_req_out
+					verify_mprime_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+	size_t cmd_size;
+
+	if (!dev || !stream_ready || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	cmd_size = struct_size(verify_mprime_in, streams, data->k);
+	if (cmd_size == SIZE_MAX)
+		return -EINVAL;
+
+	verify_mprime_in = kzalloc(cmd_size, GFP_KERNEL);
+	if (!verify_mprime_in)
+		return -ENOMEM;
+
+	verify_mprime_in->header.api_version = HDCP_API_VERSION;
+	verify_mprime_in->header.command_id = WIRED_REPEATER_AUTH_STREAM_REQ;
+	verify_mprime_in->header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_mprime_in->header.buffer_len =
+			WIRED_CMD_BUF_LEN_REPEATER_AUTH_STREAM_REQ_MIN_IN;
+
+	verify_mprime_in->port.integrated_port_type = data->port_type;
+	verify_mprime_in->port.physical_port = (u8)data->fw_ddi;
+	verify_mprime_in->port.attached_transcoder = (u8)data->fw_tc;
+
+	memcpy(verify_mprime_in->m_prime, stream_ready->m_prime, HDCP_2_2_MPRIME_LEN);
+	drm_hdcp_cpu_to_be24(verify_mprime_in->seq_num_m, data->seq_num_m);
+
+	memcpy(verify_mprime_in->streams, data->streams,
+	       array_size(data->k, sizeof(*data->streams)));
+
+	verify_mprime_in->k = cpu_to_be16(data->k);
+
+	byte = mei_cldev_send(cldev, (u8 *)verify_mprime_in, cmd_size);
+	kfree(verify_mprime_in);
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_mprime_out,
+			      sizeof(verify_mprime_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_mprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_REPEATER_AUTH_STREAM_REQ,
+			verify_mprime_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_enable_authentication() - Mark a port as authenticated
+ * through ME FW
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int mei_hdcp_enable_authentication(struct device *dev,
+					  struct hdcp_port_data *data)
+{
+	struct wired_cmd_enable_auth_in enable_auth_in = { { 0 } };
+	struct wired_cmd_enable_auth_out enable_auth_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	enable_auth_in.header.api_version = HDCP_API_VERSION;
+	enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
+	enable_auth_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	enable_auth_in.header.buffer_len = WIRED_CMD_BUF_LEN_ENABLE_AUTH_IN;
+
+	enable_auth_in.port.integrated_port_type = data->port_type;
+	enable_auth_in.port.physical_port = (u8)data->fw_ddi;
+	enable_auth_in.port.attached_transcoder = (u8)data->fw_tc;
+	enable_auth_in.stream_type = data->streams[0].stream_type;
+
+	byte = mei_cldev_send(cldev, (u8 *)&enable_auth_in,
+			      sizeof(enable_auth_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&enable_auth_out,
+			      sizeof(enable_auth_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (enable_auth_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_ENABLE_AUTH, enable_auth_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_hdcp_close_session() - Close the Wired HDCP Tx session of ME FW per port.
+ * This also disables the authenticated state of the port.
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int
+mei_hdcp_close_session(struct device *dev, struct hdcp_port_data *data)
+{
+	struct wired_cmd_close_session_in session_close_in = { { 0 } };
+	struct wired_cmd_close_session_out session_close_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	session_close_in.header.api_version = HDCP_API_VERSION;
+	session_close_in.header.command_id = WIRED_CLOSE_SESSION;
+	session_close_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	session_close_in.header.buffer_len =
+				WIRED_CMD_BUF_LEN_CLOSE_SESSION_IN;
+
+	session_close_in.port.integrated_port_type = data->port_type;
+	session_close_in.port.physical_port = (u8)data->fw_ddi;
+	session_close_in.port.attached_transcoder = (u8)data->fw_tc;
+
+	byte = mei_cldev_send(cldev, (u8 *)&session_close_in,
+			      sizeof(session_close_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&session_close_out,
+			      sizeof(session_close_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (session_close_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "Session Close Failed. status: 0x%X\n",
+			session_close_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static const struct i915_hdcp_component_ops mei_hdcp_ops = {
+	.owner = THIS_MODULE,
+	.initiate_hdcp2_session = mei_hdcp_initiate_session,
+	.verify_receiver_cert_prepare_km =
+				mei_hdcp_verify_receiver_cert_prepare_km,
+	.verify_hprime = mei_hdcp_verify_hprime,
+	.store_pairing_info = mei_hdcp_store_pairing_info,
+	.initiate_locality_check = mei_hdcp_initiate_locality_check,
+	.verify_lprime = mei_hdcp_verify_lprime,
+	.get_session_key = mei_hdcp_get_session_key,
+	.repeater_check_flow_prepare_ack =
+				mei_hdcp_repeater_check_flow_prepare_ack,
+	.verify_mprime = mei_hdcp_verify_mprime,
+	.enable_hdcp_authentication = mei_hdcp_enable_authentication,
+	.close_hdcp_session = mei_hdcp_close_session,
+};
+
+static int mei_component_master_bind(struct device *dev)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct i915_hdcp_comp_master *comp_master =
+						mei_cldev_get_drvdata(cldev);
+	int ret;
+
+	dev_dbg(dev, "%s\n", __func__);
+	comp_master->ops = &mei_hdcp_ops;
+	comp_master->mei_dev = dev;
+	ret = component_bind_all(dev, comp_master);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void mei_component_master_unbind(struct device *dev)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct i915_hdcp_comp_master *comp_master =
+						mei_cldev_get_drvdata(cldev);
+
+	dev_dbg(dev, "%s\n", __func__);
+	component_unbind_all(dev, comp_master);
+}
+
+static const struct component_master_ops mei_component_master_ops = {
+	.bind = mei_component_master_bind,
+	.unbind = mei_component_master_unbind,
+};
+
+/**
+ * mei_hdcp_component_match - compare function for matching mei hdcp.
+ *
+ *    The function checks if the driver is i915, the subcomponent is HDCP
+ *    and the grand parent of hdcp and the parent of i915 are the same
+ *    PCH device.
+ *
+ * @dev: master device
+ * @subcomponent: subcomponent to match (I915_COMPONENT_HDCP)
+ * @data: compare data (mei hdcp device)
+ *
+ * Return:
+ * * 1 - if components match
+ * * 0 - otherwise
+ */
+static int mei_hdcp_component_match(struct device *dev, int subcomponent,
+				    void *data)
+{
+	struct device *base = data;
+
+	if (strcmp(dev->driver->name, "i915") ||
+	    subcomponent != I915_COMPONENT_HDCP)
+		return 0;
+
+	base = base->parent;
+	if (!base)
+		return 0;
+
+	base = base->parent;
+	dev = dev->parent;
+
+	return (base && dev && dev == base);
+}
+
+static int mei_hdcp_probe(struct mei_cl_device *cldev,
+			  const struct mei_cl_device_id *id)
+{
+	struct i915_hdcp_comp_master *comp_master;
+	struct component_match *master_match;
+	int ret;
+
+	ret = mei_cldev_enable(cldev);
+	if (ret < 0) {
+		dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret);
+		goto enable_err_exit;
+	}
+
+	comp_master = kzalloc(sizeof(*comp_master), GFP_KERNEL);
+	if (!comp_master) {
+		ret = -ENOMEM;
+		goto err_exit;
+	}
+
+	master_match = NULL;
+	component_match_add_typed(&cldev->dev, &master_match,
+				  mei_hdcp_component_match, &cldev->dev);
+	if (IS_ERR_OR_NULL(master_match)) {
+		ret = -ENOMEM;
+		goto err_exit;
+	}
+
+	mei_cldev_set_drvdata(cldev, comp_master);
+	ret = component_master_add_with_match(&cldev->dev,
+					      &mei_component_master_ops,
+					      master_match);
+	if (ret < 0) {
+		dev_err(&cldev->dev, "Master comp add failed %d\n", ret);
+		goto err_exit;
+	}
+
+	return 0;
+
+err_exit:
+	mei_cldev_set_drvdata(cldev, NULL);
+	kfree(comp_master);
+	mei_cldev_disable(cldev);
+enable_err_exit:
+	return ret;
+}
+
+static int mei_hdcp_remove(struct mei_cl_device *cldev)
+{
+	struct i915_hdcp_comp_master *comp_master =
+						mei_cldev_get_drvdata(cldev);
+
+	component_master_del(&cldev->dev, &mei_component_master_ops);
+	kfree(comp_master);
+	mei_cldev_set_drvdata(cldev, NULL);
+
+	return mei_cldev_disable(cldev);
+}
+
+#define MEI_UUID_HDCP GUID_INIT(0xB638AB7E, 0x94E2, 0x4EA2, 0xA5, \
+				0x52, 0xD1, 0xC5, 0x4B, 0x62, 0x7F, 0x04)
+
+static const struct mei_cl_device_id mei_hdcp_tbl[] = {
+	{ .uuid = MEI_UUID_HDCP, .version = MEI_CL_VERSION_ANY },
+	{ }
+};
+MODULE_DEVICE_TABLE(mei, mei_hdcp_tbl);
+
+static struct mei_cl_driver mei_hdcp_driver = {
+	.id_table = mei_hdcp_tbl,
+	.name = KBUILD_MODNAME,
+	.probe = mei_hdcp_probe,
+	.remove	= mei_hdcp_remove,
+};
+
+module_mei_cl_driver(mei_hdcp_driver);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("MEI HDCP");
diff --git a/drivers/misc/mei/hdcp/mei_hdcp.h b/drivers/misc/mei/hdcp/mei_hdcp.h
new file mode 100644
index 000000000..834757f5e
--- /dev/null
+++ b/drivers/misc/mei/hdcp/mei_hdcp.h
@@ -0,0 +1,368 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright © 2019 Intel Corporation
+ *
+ * Authors:
+ * Ramalingam C <ramalingam.c@intel.com>
+ */
+
+#ifndef __MEI_HDCP_H__
+#define __MEI_HDCP_H__
+
+#include <drm/drm_hdcp.h>
+
+/* me_hdcp_status: Enumeration of all HDCP Status Codes */
+enum me_hdcp_status {
+	ME_HDCP_STATUS_SUCCESS			= 0x0000,
+
+	/* WiDi Generic Status Codes */
+	ME_HDCP_STATUS_INTERNAL_ERROR		= 0x1000,
+	ME_HDCP_STATUS_UNKNOWN_ERROR		= 0x1001,
+	ME_HDCP_STATUS_INCORRECT_API_VERSION	= 0x1002,
+	ME_HDCP_STATUS_INVALID_FUNCTION		= 0x1003,
+	ME_HDCP_STATUS_INVALID_BUFFER_LENGTH	= 0x1004,
+	ME_HDCP_STATUS_INVALID_PARAMS		= 0x1005,
+	ME_HDCP_STATUS_AUTHENTICATION_FAILED	= 0x1006,
+
+	/* WiDi Status Codes */
+	ME_HDCP_INVALID_SESSION_STATE		= 0x6000,
+	ME_HDCP_SRM_FRAGMENT_UNEXPECTED		= 0x6001,
+	ME_HDCP_SRM_INVALID_LENGTH		= 0x6002,
+	ME_HDCP_SRM_FRAGMENT_OFFSET_INVALID	= 0x6003,
+	ME_HDCP_SRM_VERIFICATION_FAILED		= 0x6004,
+	ME_HDCP_SRM_VERSION_TOO_OLD		= 0x6005,
+	ME_HDCP_RX_CERT_VERIFICATION_FAILED	= 0x6006,
+	ME_HDCP_RX_REVOKED			= 0x6007,
+	ME_HDCP_H_VERIFICATION_FAILED		= 0x6008,
+	ME_HDCP_REPEATER_CHECK_UNEXPECTED	= 0x6009,
+	ME_HDCP_TOPOLOGY_MAX_EXCEEDED		= 0x600A,
+	ME_HDCP_V_VERIFICATION_FAILED		= 0x600B,
+	ME_HDCP_L_VERIFICATION_FAILED		= 0x600C,
+	ME_HDCP_STREAM_KEY_ALLOC_FAILED		= 0x600D,
+	ME_HDCP_BASE_KEY_RESET_FAILED		= 0x600E,
+	ME_HDCP_NONCE_GENERATION_FAILED		= 0x600F,
+	ME_HDCP_STATUS_INVALID_E_KEY_STATE	= 0x6010,
+	ME_HDCP_STATUS_INVALID_CS_ICV		= 0x6011,
+	ME_HDCP_STATUS_INVALID_KB_KEY_STATE	= 0x6012,
+	ME_HDCP_STATUS_INVALID_PAVP_MODE_ICV	= 0x6013,
+	ME_HDCP_STATUS_INVALID_PAVP_MODE	= 0x6014,
+	ME_HDCP_STATUS_LC_MAX_ATTEMPTS		= 0x6015,
+
+	/* New status for HDCP 2.1 */
+	ME_HDCP_STATUS_MISMATCH_IN_M		= 0x6016,
+
+	/* New status code for HDCP 2.2 Rx */
+	ME_HDCP_STATUS_RX_PROV_NOT_ALLOWED	= 0x6017,
+	ME_HDCP_STATUS_RX_PROV_WRONG_SUBJECT	= 0x6018,
+	ME_HDCP_RX_NEEDS_PROVISIONING		= 0x6019,
+	ME_HDCP_BKSV_ICV_AUTH_FAILED		= 0x6020,
+	ME_HDCP_STATUS_INVALID_STREAM_ID	= 0x6021,
+	ME_HDCP_STATUS_CHAIN_NOT_INITIALIZED	= 0x6022,
+	ME_HDCP_FAIL_NOT_EXPECTED		= 0x6023,
+	ME_HDCP_FAIL_HDCP_OFF			= 0x6024,
+	ME_HDCP_FAIL_INVALID_PAVP_MEMORY_MODE	= 0x6025,
+	ME_HDCP_FAIL_AES_ECB_FAILURE		= 0x6026,
+	ME_HDCP_FEATURE_NOT_SUPPORTED		= 0x6027,
+	ME_HDCP_DMA_READ_ERROR			= 0x6028,
+	ME_HDCP_DMA_WRITE_ERROR			= 0x6029,
+	ME_HDCP_FAIL_INVALID_PACKET_SIZE	= 0x6030,
+	ME_HDCP_H264_PARSING_ERROR		= 0x6031,
+	ME_HDCP_HDCP2_ERRATA_VIDEO_VIOLATION	= 0x6032,
+	ME_HDCP_HDCP2_ERRATA_AUDIO_VIOLATION	= 0x6033,
+	ME_HDCP_TX_ACTIVE_ERROR			= 0x6034,
+	ME_HDCP_MODE_CHANGE_ERROR		= 0x6035,
+	ME_HDCP_STREAM_TYPE_ERROR		= 0x6036,
+	ME_HDCP_STREAM_MANAGE_NOT_POSSIBLE	= 0x6037,
+
+	ME_HDCP_STATUS_PORT_INVALID_COMMAND	= 0x6038,
+	ME_HDCP_STATUS_UNSUPPORTED_PROTOCOL	= 0x6039,
+	ME_HDCP_STATUS_INVALID_PORT_INDEX	= 0x603a,
+	ME_HDCP_STATUS_TX_AUTH_NEEDED		= 0x603b,
+	ME_HDCP_STATUS_NOT_INTEGRATED_PORT	= 0x603c,
+	ME_HDCP_STATUS_SESSION_MAX_REACHED	= 0x603d,
+
+	/* hdcp capable bit is not set in rx_caps(error is unique to DP) */
+	ME_HDCP_STATUS_NOT_HDCP_CAPABLE		= 0x6041,
+
+	ME_HDCP_STATUS_INVALID_STREAM_COUNT	= 0x6042,
+};
+
+#define HDCP_API_VERSION				0x00010000
+
+#define HDCP_M_LEN					16
+#define HDCP_KH_LEN					16
+
+/* Payload Buffer size(Excluding Header) for CMDs and corresponding response */
+/* Wired_Tx_AKE  */
+#define	WIRED_CMD_BUF_LEN_INITIATE_HDCP2_SESSION_IN	(4 + 1)
+#define	WIRED_CMD_BUF_LEN_INITIATE_HDCP2_SESSION_OUT	(4 + 8 + 3)
+
+#define	WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_IN	(4 + 522 + 8 + 3)
+#define	WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_MIN_OUT	(4 + 1 + 3 + 16 + 16)
+#define	WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_MAX_OUT	(4 + 1 + 3 + 128)
+
+#define	WIRED_CMD_BUF_LEN_AKE_SEND_HPRIME_IN		(4 + 32)
+#define	WIRED_CMD_BUF_LEN_AKE_SEND_HPRIME_OUT		(4)
+
+#define	WIRED_CMD_BUF_LEN_SEND_PAIRING_INFO_IN		(4 + 16)
+#define	WIRED_CMD_BUF_LEN_SEND_PAIRING_INFO_OUT		(4)
+
+#define	WIRED_CMD_BUF_LEN_CLOSE_SESSION_IN		(4)
+#define	WIRED_CMD_BUF_LEN_CLOSE_SESSION_OUT		(4)
+
+/* Wired_Tx_LC */
+#define	WIRED_CMD_BUF_LEN_INIT_LOCALITY_CHECK_IN	(4)
+#define	WIRED_CMD_BUF_LEN_INIT_LOCALITY_CHECK_OUT	(4 + 8)
+
+#define	WIRED_CMD_BUF_LEN_VALIDATE_LOCALITY_IN		(4 + 32)
+#define	WIRED_CMD_BUF_LEN_VALIDATE_LOCALITY_OUT		(4)
+
+/* Wired_Tx_SKE */
+#define	WIRED_CMD_BUF_LEN_GET_SESSION_KEY_IN		(4)
+#define	WIRED_CMD_BUF_LEN_GET_SESSION_KEY_OUT		(4 + 16 + 8)
+
+/* Wired_Tx_SKE */
+#define	WIRED_CMD_BUF_LEN_ENABLE_AUTH_IN		(4 + 1)
+#define	WIRED_CMD_BUF_LEN_ENABLE_AUTH_OUT		(4)
+
+/* Wired_Tx_Repeater */
+#define	WIRED_CMD_BUF_LEN_VERIFY_REPEATER_IN		(4 + 2 + 3 + 16 + 155)
+#define	WIRED_CMD_BUF_LEN_VERIFY_REPEATER_OUT		(4 + 1 + 16)
+
+#define	WIRED_CMD_BUF_LEN_REPEATER_AUTH_STREAM_REQ_MIN_IN	(4 + 3 + \
+								32 + 2 + 2)
+
+#define	WIRED_CMD_BUF_LEN_REPEATER_AUTH_STREAM_REQ_OUT		(4)
+
+/* hdcp_command_id: Enumeration of all WIRED HDCP Command IDs */
+enum hdcp_command_id {
+	_WIDI_COMMAND_BASE		= 0x00030000,
+	WIDI_INITIATE_HDCP2_SESSION	= _WIDI_COMMAND_BASE,
+	HDCP_GET_SRM_STATUS,
+	HDCP_SEND_SRM_FRAGMENT,
+
+	/* The wired HDCP Tx commands */
+	_WIRED_COMMAND_BASE		= 0x00031000,
+	WIRED_INITIATE_HDCP2_SESSION	= _WIRED_COMMAND_BASE,
+	WIRED_VERIFY_RECEIVER_CERT,
+	WIRED_AKE_SEND_HPRIME,
+	WIRED_AKE_SEND_PAIRING_INFO,
+	WIRED_INIT_LOCALITY_CHECK,
+	WIRED_VALIDATE_LOCALITY,
+	WIRED_GET_SESSION_KEY,
+	WIRED_ENABLE_AUTH,
+	WIRED_VERIFY_REPEATER,
+	WIRED_REPEATER_AUTH_STREAM_REQ,
+	WIRED_CLOSE_SESSION,
+
+	_WIRED_COMMANDS_COUNT,
+};
+
+union encrypted_buff {
+	u8		e_kpub_km[HDCP_2_2_E_KPUB_KM_LEN];
+	u8		e_kh_km_m[HDCP_2_2_E_KH_KM_M_LEN];
+	struct {
+		u8	e_kh_km[HDCP_KH_LEN];
+		u8	m[HDCP_M_LEN];
+	} __packed;
+};
+
+/* HDCP HECI message header. All header values are little endian. */
+struct hdcp_cmd_header {
+	u32			api_version;
+	u32			command_id;
+	enum me_hdcp_status	status;
+	/* Length of the HECI message (excluding the header) */
+	u32			buffer_len;
+} __packed;
+
+/* Empty command request or response. No data follows the header. */
+struct hdcp_cmd_no_data {
+	struct hdcp_cmd_header header;
+} __packed;
+
+/* Uniquely identifies the hdcp port being addressed for a given command. */
+struct hdcp_port_id {
+	u8	integrated_port_type;
+	/* physical_port is used until Gen11.5. Must be zero for Gen11.5+ */
+	u8	physical_port;
+	/* attached_transcoder is for Gen11.5+. Set to zero for <Gen11.5 */
+	u8	attached_transcoder;
+	u8	reserved;
+} __packed;
+
+/*
+ * Data structures for integrated wired HDCP2 Tx in
+ * support of the AKE protocol
+ */
+/* HECI struct for integrated wired HDCP Tx session initiation. */
+struct wired_cmd_initiate_hdcp2_session_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			protocol; /* for HDMI vs DP */
+} __packed;
+
+struct wired_cmd_initiate_hdcp2_session_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			r_tx[HDCP_2_2_RTX_LEN];
+	struct hdcp2_tx_caps	tx_caps;
+} __packed;
+
+/* HECI struct for ending an integrated wired HDCP Tx session. */
+struct wired_cmd_close_session_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+struct wired_cmd_close_session_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+/* HECI struct for integrated wired HDCP Tx Rx Cert verification. */
+struct wired_cmd_verify_receiver_cert_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	struct hdcp2_cert_rx	cert_rx;
+	u8			r_rx[HDCP_2_2_RRX_LEN];
+	u8			rx_caps[HDCP_2_2_RXCAPS_LEN];
+} __packed;
+
+struct wired_cmd_verify_receiver_cert_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			km_stored;
+	u8			reserved[3];
+	union encrypted_buff	ekm_buff;
+} __packed;
+
+/* HECI struct for verification of Rx's Hprime in a HDCP Tx session */
+struct wired_cmd_ake_send_hprime_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			h_prime[HDCP_2_2_H_PRIME_LEN];
+} __packed;
+
+struct wired_cmd_ake_send_hprime_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+/*
+ * HECI struct for sending in AKE pairing data generated by the Rx in an
+ * integrated wired HDCP Tx session.
+ */
+struct wired_cmd_ake_send_pairing_info_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			e_kh_km[HDCP_2_2_E_KH_KM_LEN];
+} __packed;
+
+struct wired_cmd_ake_send_pairing_info_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+/* Data structures for integrated wired HDCP2 Tx in support of the LC protocol*/
+/*
+ * HECI struct for initiating locality check with an
+ * integrated wired HDCP Tx session.
+ */
+struct wired_cmd_init_locality_check_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+struct wired_cmd_init_locality_check_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			r_n[HDCP_2_2_RN_LEN];
+} __packed;
+
+/*
+ * HECI struct for validating an Rx's LPrime value in an
+ * integrated wired HDCP Tx session.
+ */
+struct wired_cmd_validate_locality_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			l_prime[HDCP_2_2_L_PRIME_LEN];
+} __packed;
+
+struct wired_cmd_validate_locality_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+/*
+ * Data structures for integrated wired HDCP2 Tx in support of the
+ * SKE protocol
+ */
+/* HECI struct for creating session key */
+struct wired_cmd_get_session_key_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+struct wired_cmd_get_session_key_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			e_dkey_ks[HDCP_2_2_E_DKEY_KS_LEN];
+	u8			r_iv[HDCP_2_2_RIV_LEN];
+} __packed;
+
+/* HECI struct for the Tx enable authentication command */
+struct wired_cmd_enable_auth_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			stream_type;
+} __packed;
+
+struct wired_cmd_enable_auth_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+
+/*
+ * Data structures for integrated wired HDCP2 Tx in support of
+ * the repeater protocols
+ */
+/*
+ * HECI struct for verifying the downstream repeater's HDCP topology in an
+ * integrated wired HDCP Tx session.
+ */
+struct wired_cmd_verify_repeater_in {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			rx_info[HDCP_2_2_RXINFO_LEN];
+	u8			seq_num_v[HDCP_2_2_SEQ_NUM_LEN];
+	u8			v_prime[HDCP_2_2_V_PRIME_HALF_LEN];
+	u8			receiver_ids[HDCP_2_2_RECEIVER_IDS_MAX_LEN];
+} __packed;
+
+struct wired_cmd_verify_repeater_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+	u8			content_type_supported;
+	u8			v[HDCP_2_2_V_PRIME_HALF_LEN];
+} __packed;
+
+/*
+ * HECI struct in support of stream management in an
+ * integrated wired HDCP Tx session.
+ */
+struct wired_cmd_repeater_auth_stream_req_in {
+	struct hdcp_cmd_header		header;
+	struct hdcp_port_id		port;
+	u8				seq_num_m[HDCP_2_2_SEQ_NUM_LEN];
+	u8				m_prime[HDCP_2_2_MPRIME_LEN];
+	__be16				k;
+	struct hdcp2_streamid_type	streams[];
+} __packed;
+
+struct wired_cmd_repeater_auth_stream_req_out {
+	struct hdcp_cmd_header	header;
+	struct hdcp_port_id	port;
+} __packed;
+#endif /* __MEI_HDCP_H__ */
diff --git a/drivers/misc/mei/hw-me-regs.h b/drivers/misc/mei/hw-me-regs.h
new file mode 100644
index 000000000..eabbdf17b
--- /dev/null
+++ b/drivers/misc/mei/hw-me-regs.h
@@ -0,0 +1,206 @@
+/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
+/*
+ * Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+#ifndef _MEI_HW_MEI_REGS_H_
+#define _MEI_HW_MEI_REGS_H_
+
+/*
+ * MEI device IDs
+ */
+#define MEI_DEV_ID_82946GZ    0x2974  /* 82946GZ/GL */
+#define MEI_DEV_ID_82G35      0x2984  /* 82G35 Express */
+#define MEI_DEV_ID_82Q965     0x2994  /* 82Q963/Q965 */
+#define MEI_DEV_ID_82G965     0x29A4  /* 82P965/G965 */
+
+#define MEI_DEV_ID_82GM965    0x2A04  /* Mobile PM965/GM965 */
+#define MEI_DEV_ID_82GME965   0x2A14  /* Mobile GME965/GLE960 */
+
+#define MEI_DEV_ID_ICH9_82Q35 0x29B4  /* 82Q35 Express */
+#define MEI_DEV_ID_ICH9_82G33 0x29C4  /* 82G33/G31/P35/P31 Express */
+#define MEI_DEV_ID_ICH9_82Q33 0x29D4  /* 82Q33 Express */
+#define MEI_DEV_ID_ICH9_82X38 0x29E4  /* 82X38/X48 Express */
+#define MEI_DEV_ID_ICH9_3200  0x29F4  /* 3200/3210 Server */
+
+#define MEI_DEV_ID_ICH9_6     0x28B4  /* Bearlake */
+#define MEI_DEV_ID_ICH9_7     0x28C4  /* Bearlake */
+#define MEI_DEV_ID_ICH9_8     0x28D4  /* Bearlake */
+#define MEI_DEV_ID_ICH9_9     0x28E4  /* Bearlake */
+#define MEI_DEV_ID_ICH9_10    0x28F4  /* Bearlake */
+
+#define MEI_DEV_ID_ICH9M_1    0x2A44  /* Cantiga */
+#define MEI_DEV_ID_ICH9M_2    0x2A54  /* Cantiga */
+#define MEI_DEV_ID_ICH9M_3    0x2A64  /* Cantiga */
+#define MEI_DEV_ID_ICH9M_4    0x2A74  /* Cantiga */
+
+#define MEI_DEV_ID_ICH10_1    0x2E04  /* Eaglelake */
+#define MEI_DEV_ID_ICH10_2    0x2E14  /* Eaglelake */
+#define MEI_DEV_ID_ICH10_3    0x2E24  /* Eaglelake */
+#define MEI_DEV_ID_ICH10_4    0x2E34  /* Eaglelake */
+
+#define MEI_DEV_ID_IBXPK_1    0x3B64  /* Calpella */
+#define MEI_DEV_ID_IBXPK_2    0x3B65  /* Calpella */
+
+#define MEI_DEV_ID_CPT_1      0x1C3A  /* Couger Point */
+#define MEI_DEV_ID_PBG_1      0x1D3A  /* C600/X79 Patsburg */
+
+#define MEI_DEV_ID_PPT_1      0x1E3A  /* Panther Point */
+#define MEI_DEV_ID_PPT_2      0x1CBA  /* Panther Point */
+#define MEI_DEV_ID_PPT_3      0x1DBA  /* Panther Point */
+
+#define MEI_DEV_ID_LPT_H      0x8C3A  /* Lynx Point H */
+#define MEI_DEV_ID_LPT_W      0x8D3A  /* Lynx Point - Wellsburg */
+#define MEI_DEV_ID_LPT_LP     0x9C3A  /* Lynx Point LP */
+#define MEI_DEV_ID_LPT_HR     0x8CBA  /* Lynx Point H Refresh */
+
+#define MEI_DEV_ID_WPT_LP     0x9CBA  /* Wildcat Point LP */
+#define MEI_DEV_ID_WPT_LP_2   0x9CBB  /* Wildcat Point LP 2 */
+
+#define MEI_DEV_ID_SPT        0x9D3A  /* Sunrise Point */
+#define MEI_DEV_ID_SPT_2      0x9D3B  /* Sunrise Point 2 */
+#define MEI_DEV_ID_SPT_3      0x9D3E  /* Sunrise Point 3 (iToutch) */
+#define MEI_DEV_ID_SPT_H      0xA13A  /* Sunrise Point H */
+#define MEI_DEV_ID_SPT_H_2    0xA13B  /* Sunrise Point H 2 */
+
+#define MEI_DEV_ID_LBG        0xA1BA  /* Lewisburg (SPT) */
+
+#define MEI_DEV_ID_BXT_M      0x1A9A  /* Broxton M */
+#define MEI_DEV_ID_APL_I      0x5A9A  /* Apollo Lake I */
+
+#define MEI_DEV_ID_DNV_IE     0x19E5  /* Denverton IE */
+
+#define MEI_DEV_ID_GLK        0x319A  /* Gemini Lake */
+
+#define MEI_DEV_ID_KBP        0xA2BA  /* Kaby Point */
+#define MEI_DEV_ID_KBP_2      0xA2BB  /* Kaby Point 2 */
+#define MEI_DEV_ID_KBP_3      0xA2BE  /* Kaby Point 3 (iTouch) */
+
+#define MEI_DEV_ID_CNP_LP     0x9DE0  /* Cannon Point LP */
+#define MEI_DEV_ID_CNP_LP_3   0x9DE4  /* Cannon Point LP 3 (iTouch) */
+#define MEI_DEV_ID_CNP_H      0xA360  /* Cannon Point H */
+#define MEI_DEV_ID_CNP_H_3    0xA364  /* Cannon Point H 3 (iTouch) */
+
+#define MEI_DEV_ID_CMP_LP     0x02e0  /* Comet Point LP */
+#define MEI_DEV_ID_CMP_LP_3   0x02e4  /* Comet Point LP 3 (iTouch) */
+
+#define MEI_DEV_ID_CMP_V      0xA3BA  /* Comet Point Lake V */
+
+#define MEI_DEV_ID_CMP_H      0x06e0  /* Comet Lake H */
+#define MEI_DEV_ID_CMP_H_3    0x06e4  /* Comet Lake H 3 (iTouch) */
+
+#define MEI_DEV_ID_CDF        0x18D3  /* Cedar Fork */
+
+#define MEI_DEV_ID_ICP_LP     0x34E0  /* Ice Lake Point LP */
+#define MEI_DEV_ID_ICP_N      0x38E0  /* Ice Lake Point N */
+
+#define MEI_DEV_ID_JSP_N      0x4DE0  /* Jasper Lake Point N */
+
+#define MEI_DEV_ID_TGP_LP     0xA0E0  /* Tiger Lake Point LP */
+#define MEI_DEV_ID_TGP_H      0x43E0  /* Tiger Lake Point H */
+
+#define MEI_DEV_ID_MCC        0x4B70  /* Mule Creek Canyon (EHL) */
+#define MEI_DEV_ID_MCC_4      0x4B75  /* Mule Creek Canyon 4 (EHL) */
+
+#define MEI_DEV_ID_EBG        0x1BE0  /* Emmitsburg WS */
+
+#define MEI_DEV_ID_ADP_S      0x7AE8  /* Alder Lake Point S */
+#define MEI_DEV_ID_ADP_LP     0x7A60  /* Alder Lake Point LP */
+#define MEI_DEV_ID_ADP_P      0x51E0  /* Alder Lake Point P */
+#define MEI_DEV_ID_ADP_N      0x54E0  /* Alder Lake Point N */
+
+#define MEI_DEV_ID_RPL_S      0x7A68  /* Raptor Lake Point S */
+
+#define MEI_DEV_ID_MTL_M      0x7E70  /* Meteor Lake Point M */
+
+/*
+ * MEI HW Section
+ */
+
+/* Host Firmware Status Registers in PCI Config Space */
+#define PCI_CFG_HFS_1         0x40
+#  define PCI_CFG_HFS_1_D0I3_MSK     0x80000000
+#  define PCI_CFG_HFS_1_OPMODE_MSK 0xf0000 /* OP MODE Mask: SPS <= 4.0 */
+#  define PCI_CFG_HFS_1_OPMODE_SPS 0xf0000 /* SPS SKU : SPS <= 4.0 */
+#define PCI_CFG_HFS_2         0x48
+#define PCI_CFG_HFS_3         0x60
+#  define PCI_CFG_HFS_3_FW_SKU_MSK   0x00000070
+#  define PCI_CFG_HFS_3_FW_SKU_SPS   0x00000060
+#define PCI_CFG_HFS_4         0x64
+#define PCI_CFG_HFS_5         0x68
+#define PCI_CFG_HFS_6         0x6C
+
+/* MEI registers */
+/* H_CB_WW - Host Circular Buffer (CB) Write Window register */
+#define H_CB_WW    0
+/* H_CSR - Host Control Status register */
+#define H_CSR      4
+/* ME_CB_RW - ME Circular Buffer Read Window register (read only) */
+#define ME_CB_RW   8
+/* ME_CSR_HA - ME Control Status Host Access register (read only) */
+#define ME_CSR_HA  0xC
+/* H_HGC_CSR - PGI register */
+#define H_HPG_CSR  0x10
+/* H_D0I3C - D0I3 Control  */
+#define H_D0I3C    0x800
+
+/* register bits of H_CSR (Host Control Status register) */
+/* Host Circular Buffer Depth - maximum number of 32-bit entries in CB */
+#define H_CBD             0xFF000000
+/* Host Circular Buffer Write Pointer */
+#define H_CBWP            0x00FF0000
+/* Host Circular Buffer Read Pointer */
+#define H_CBRP            0x0000FF00
+/* Host Reset */
+#define H_RST             0x00000010
+/* Host Ready */
+#define H_RDY             0x00000008
+/* Host Interrupt Generate */
+#define H_IG              0x00000004
+/* Host Interrupt Status */
+#define H_IS              0x00000002
+/* Host Interrupt Enable */
+#define H_IE              0x00000001
+/* Host D0I3 Interrupt Enable */
+#define H_D0I3C_IE        0x00000020
+/* Host D0I3 Interrupt Status */
+#define H_D0I3C_IS        0x00000040
+
+/* H_CSR masks */
+#define H_CSR_IE_MASK     (H_IE | H_D0I3C_IE)
+#define H_CSR_IS_MASK     (H_IS | H_D0I3C_IS)
+
+/* register bits of ME_CSR_HA (ME Control Status Host Access register) */
+/* ME CB (Circular Buffer) Depth HRA (Host Read Access) - host read only
+access to ME_CBD */
+#define ME_CBD_HRA        0xFF000000
+/* ME CB Write Pointer HRA - host read only access to ME_CBWP */
+#define ME_CBWP_HRA       0x00FF0000
+/* ME CB Read Pointer HRA - host read only access to ME_CBRP */
+#define ME_CBRP_HRA       0x0000FF00
+/* ME Power Gate Isolation Capability HRA  - host ready only access */
+#define ME_PGIC_HRA       0x00000040
+/* ME Reset HRA - host read only access to ME_RST */
+#define ME_RST_HRA        0x00000010
+/* ME Ready HRA - host read only access to ME_RDY */
+#define ME_RDY_HRA        0x00000008
+/* ME Interrupt Generate HRA - host read only access to ME_IG */
+#define ME_IG_HRA         0x00000004
+/* ME Interrupt Status HRA - host read only access to ME_IS */
+#define ME_IS_HRA         0x00000002
+/* ME Interrupt Enable HRA - host read only access to ME_IE */
+#define ME_IE_HRA         0x00000001
+/* TRC control shadow register */
+#define ME_TRC            0x00000030
+
+/* H_HPG_CSR register bits */
+#define H_HPG_CSR_PGIHEXR 0x00000001
+#define H_HPG_CSR_PGI     0x00000002
+
+/* H_D0I3C register bits */
+#define H_D0I3C_CIP      0x00000001
+#define H_D0I3C_IR       0x00000002
+#define H_D0I3C_I3       0x00000004
+#define H_D0I3C_RR       0x00000008
+
+#endif /* _MEI_HW_MEI_REGS_H_ */
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
new file mode 100644
index 000000000..cda0829ac
--- /dev/null
+++ b/drivers/misc/mei/hw-me.c
@@ -0,0 +1,1633 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/pci.h>
+
+#include <linux/kthread.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/sizes.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+
+#include "hw-me.h"
+#include "hw-me-regs.h"
+
+#include "mei-trace.h"
+
+/**
+ * mei_me_reg_read - Reads 32bit data from the mei device
+ *
+ * @hw: the me hardware structure
+ * @offset: offset from which to read the data
+ *
+ * Return: register value (u32)
+ */
+static inline u32 mei_me_reg_read(const struct mei_me_hw *hw,
+			       unsigned long offset)
+{
+	return ioread32(hw->mem_addr + offset);
+}
+
+
+/**
+ * mei_me_reg_write - Writes 32bit data to the mei device
+ *
+ * @hw: the me hardware structure
+ * @offset: offset from which to write the data
+ * @value: register value to write (u32)
+ */
+static inline void mei_me_reg_write(const struct mei_me_hw *hw,
+				 unsigned long offset, u32 value)
+{
+	iowrite32(value, hw->mem_addr + offset);
+}
+
+/**
+ * mei_me_mecbrw_read - Reads 32bit data from ME circular buffer
+ *  read window register
+ *
+ * @dev: the device structure
+ *
+ * Return: ME_CB_RW register value (u32)
+ */
+static inline u32 mei_me_mecbrw_read(const struct mei_device *dev)
+{
+	return mei_me_reg_read(to_me_hw(dev), ME_CB_RW);
+}
+
+/**
+ * mei_me_hcbww_write - write 32bit data to the host circular buffer
+ *
+ * @dev: the device structure
+ * @data: 32bit data to be written to the host circular buffer
+ */
+static inline void mei_me_hcbww_write(struct mei_device *dev, u32 data)
+{
+	mei_me_reg_write(to_me_hw(dev), H_CB_WW, data);
+}
+
+/**
+ * mei_me_mecsr_read - Reads 32bit data from the ME CSR
+ *
+ * @dev: the device structure
+ *
+ * Return: ME_CSR_HA register value (u32)
+ */
+static inline u32 mei_me_mecsr_read(const struct mei_device *dev)
+{
+	u32 reg;
+
+	reg = mei_me_reg_read(to_me_hw(dev), ME_CSR_HA);
+	trace_mei_reg_read(dev->dev, "ME_CSR_HA", ME_CSR_HA, reg);
+
+	return reg;
+}
+
+/**
+ * mei_hcsr_read - Reads 32bit data from the host CSR
+ *
+ * @dev: the device structure
+ *
+ * Return: H_CSR register value (u32)
+ */
+static inline u32 mei_hcsr_read(const struct mei_device *dev)
+{
+	u32 reg;
+
+	reg = mei_me_reg_read(to_me_hw(dev), H_CSR);
+	trace_mei_reg_read(dev->dev, "H_CSR", H_CSR, reg);
+
+	return reg;
+}
+
+/**
+ * mei_hcsr_write - writes H_CSR register to the mei device
+ *
+ * @dev: the device structure
+ * @reg: new register value
+ */
+static inline void mei_hcsr_write(struct mei_device *dev, u32 reg)
+{
+	trace_mei_reg_write(dev->dev, "H_CSR", H_CSR, reg);
+	mei_me_reg_write(to_me_hw(dev), H_CSR, reg);
+}
+
+/**
+ * mei_hcsr_set - writes H_CSR register to the mei device,
+ * and ignores the H_IS bit for it is write-one-to-zero.
+ *
+ * @dev: the device structure
+ * @reg: new register value
+ */
+static inline void mei_hcsr_set(struct mei_device *dev, u32 reg)
+{
+	reg &= ~H_CSR_IS_MASK;
+	mei_hcsr_write(dev, reg);
+}
+
+/**
+ * mei_hcsr_set_hig - set host interrupt (set H_IG)
+ *
+ * @dev: the device structure
+ */
+static inline void mei_hcsr_set_hig(struct mei_device *dev)
+{
+	u32 hcsr;
+
+	hcsr = mei_hcsr_read(dev) | H_IG;
+	mei_hcsr_set(dev, hcsr);
+}
+
+/**
+ * mei_me_d0i3c_read - Reads 32bit data from the D0I3C register
+ *
+ * @dev: the device structure
+ *
+ * Return: H_D0I3C register value (u32)
+ */
+static inline u32 mei_me_d0i3c_read(const struct mei_device *dev)
+{
+	u32 reg;
+
+	reg = mei_me_reg_read(to_me_hw(dev), H_D0I3C);
+	trace_mei_reg_read(dev->dev, "H_D0I3C", H_D0I3C, reg);
+
+	return reg;
+}
+
+/**
+ * mei_me_d0i3c_write - writes H_D0I3C register to device
+ *
+ * @dev: the device structure
+ * @reg: new register value
+ */
+static inline void mei_me_d0i3c_write(struct mei_device *dev, u32 reg)
+{
+	trace_mei_reg_write(dev->dev, "H_D0I3C", H_D0I3C, reg);
+	mei_me_reg_write(to_me_hw(dev), H_D0I3C, reg);
+}
+
+/**
+ * mei_me_trc_status - read trc status register
+ *
+ * @dev: mei device
+ * @trc: trc status register value
+ *
+ * Return: 0 on success, error otherwise
+ */
+static int mei_me_trc_status(struct mei_device *dev, u32 *trc)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (!hw->cfg->hw_trc_supported)
+		return -EOPNOTSUPP;
+
+	*trc = mei_me_reg_read(hw, ME_TRC);
+	trace_mei_reg_read(dev->dev, "ME_TRC", ME_TRC, *trc);
+
+	return 0;
+}
+
+/**
+ * mei_me_fw_status - read fw status register from pci config space
+ *
+ * @dev: mei device
+ * @fw_status: fw status register values
+ *
+ * Return: 0 on success, error otherwise
+ */
+static int mei_me_fw_status(struct mei_device *dev,
+			    struct mei_fw_status *fw_status)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	const struct mei_fw_status *fw_src = &hw->cfg->fw_status;
+	int ret;
+	int i;
+
+	if (!fw_status || !hw->read_fws)
+		return -EINVAL;
+
+	fw_status->count = fw_src->count;
+	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
+		ret = hw->read_fws(dev, fw_src->status[i],
+				   &fw_status->status[i]);
+		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_X",
+				       fw_src->status[i],
+				       fw_status->status[i]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_me_hw_config - configure hw dependent settings
+ *
+ * @dev: mei device
+ *
+ * Return:
+ *  * -EINVAL when read_fws is not set
+ *  * 0 on success
+ *
+ */
+static int mei_me_hw_config(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 hcsr, reg;
+
+	if (WARN_ON(!hw->read_fws))
+		return -EINVAL;
+
+	/* Doesn't change in runtime */
+	hcsr = mei_hcsr_read(dev);
+	hw->hbuf_depth = (hcsr & H_CBD) >> 24;
+
+	reg = 0;
+	hw->read_fws(dev, PCI_CFG_HFS_1, &reg);
+	trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
+	hw->d0i3_supported =
+		((reg & PCI_CFG_HFS_1_D0I3_MSK) == PCI_CFG_HFS_1_D0I3_MSK);
+
+	hw->pg_state = MEI_PG_OFF;
+	if (hw->d0i3_supported) {
+		reg = mei_me_d0i3c_read(dev);
+		if (reg & H_D0I3C_I3)
+			hw->pg_state = MEI_PG_ON;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_me_pg_state  - translate internal pg state
+ *   to the mei power gating state
+ *
+ * @dev:  mei device
+ *
+ * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
+ */
+static inline enum mei_pg_state mei_me_pg_state(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	return hw->pg_state;
+}
+
+static inline u32 me_intr_src(u32 hcsr)
+{
+	return hcsr & H_CSR_IS_MASK;
+}
+
+/**
+ * me_intr_disable - disables mei device interrupts
+ *      using supplied hcsr register value.
+ *
+ * @dev: the device structure
+ * @hcsr: supplied hcsr register value
+ */
+static inline void me_intr_disable(struct mei_device *dev, u32 hcsr)
+{
+	hcsr &= ~H_CSR_IE_MASK;
+	mei_hcsr_set(dev, hcsr);
+}
+
+/**
+ * me_intr_clear - clear and stop interrupts
+ *
+ * @dev: the device structure
+ * @hcsr: supplied hcsr register value
+ */
+static inline void me_intr_clear(struct mei_device *dev, u32 hcsr)
+{
+	if (me_intr_src(hcsr))
+		mei_hcsr_write(dev, hcsr);
+}
+
+/**
+ * mei_me_intr_clear - clear and stop interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_clear(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	me_intr_clear(dev, hcsr);
+}
+/**
+ * mei_me_intr_enable - enables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_enable(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	hcsr |= H_CSR_IE_MASK;
+	mei_hcsr_set(dev, hcsr);
+}
+
+/**
+ * mei_me_intr_disable - disables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_disable(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	me_intr_disable(dev, hcsr);
+}
+
+/**
+ * mei_me_synchronize_irq - wait for pending IRQ handlers
+ *
+ * @dev: the device structure
+ */
+static void mei_me_synchronize_irq(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	synchronize_irq(hw->irq);
+}
+
+/**
+ * mei_me_hw_reset_release - release device from the reset
+ *
+ * @dev: the device structure
+ */
+static void mei_me_hw_reset_release(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	hcsr |= H_IG;
+	hcsr &= ~H_RST;
+	mei_hcsr_set(dev, hcsr);
+}
+
+/**
+ * mei_me_host_set_ready - enable device
+ *
+ * @dev: mei device
+ */
+static void mei_me_host_set_ready(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	hcsr |= H_CSR_IE_MASK | H_IG | H_RDY;
+	mei_hcsr_set(dev, hcsr);
+}
+
+/**
+ * mei_me_host_is_ready - check whether the host has turned ready
+ *
+ * @dev: mei device
+ * Return: bool
+ */
+static bool mei_me_host_is_ready(struct mei_device *dev)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	return (hcsr & H_RDY) == H_RDY;
+}
+
+/**
+ * mei_me_hw_is_ready - check whether the me(hw) has turned ready
+ *
+ * @dev: mei device
+ * Return: bool
+ */
+static bool mei_me_hw_is_ready(struct mei_device *dev)
+{
+	u32 mecsr = mei_me_mecsr_read(dev);
+
+	return (mecsr & ME_RDY_HRA) == ME_RDY_HRA;
+}
+
+/**
+ * mei_me_hw_is_resetting - check whether the me(hw) is in reset
+ *
+ * @dev: mei device
+ * Return: bool
+ */
+static bool mei_me_hw_is_resetting(struct mei_device *dev)
+{
+	u32 mecsr = mei_me_mecsr_read(dev);
+
+	return (mecsr & ME_RST_HRA) == ME_RST_HRA;
+}
+
+/**
+ * mei_me_hw_ready_wait - wait until the me(hw) has turned ready
+ *  or timeout is reached
+ *
+ * @dev: mei device
+ * Return: 0 on success, error otherwise
+ */
+static int mei_me_hw_ready_wait(struct mei_device *dev)
+{
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_hw_ready,
+			dev->recvd_hw_ready,
+			mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+	if (!dev->recvd_hw_ready) {
+		dev_err(dev->dev, "wait hw ready failed\n");
+		return -ETIME;
+	}
+
+	mei_me_hw_reset_release(dev);
+	dev->recvd_hw_ready = false;
+	return 0;
+}
+
+/**
+ * mei_me_hw_start - hw start routine
+ *
+ * @dev: mei device
+ * Return: 0 on success, error otherwise
+ */
+static int mei_me_hw_start(struct mei_device *dev)
+{
+	int ret = mei_me_hw_ready_wait(dev);
+
+	if (ret)
+		return ret;
+	dev_dbg(dev->dev, "hw is ready\n");
+
+	mei_me_host_set_ready(dev);
+	return ret;
+}
+
+
+/**
+ * mei_hbuf_filled_slots - gets number of device filled buffer slots
+ *
+ * @dev: the device structure
+ *
+ * Return: number of filled slots
+ */
+static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
+{
+	u32 hcsr;
+	char read_ptr, write_ptr;
+
+	hcsr = mei_hcsr_read(dev);
+
+	read_ptr = (char) ((hcsr & H_CBRP) >> 8);
+	write_ptr = (char) ((hcsr & H_CBWP) >> 16);
+
+	return (unsigned char) (write_ptr - read_ptr);
+}
+
+/**
+ * mei_me_hbuf_is_empty - checks if host buffer is empty.
+ *
+ * @dev: the device structure
+ *
+ * Return: true if empty, false - otherwise.
+ */
+static bool mei_me_hbuf_is_empty(struct mei_device *dev)
+{
+	return mei_hbuf_filled_slots(dev) == 0;
+}
+
+/**
+ * mei_me_hbuf_empty_slots - counts write empty slots.
+ *
+ * @dev: the device structure
+ *
+ * Return: -EOVERFLOW if overflow, otherwise empty slots count
+ */
+static int mei_me_hbuf_empty_slots(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	unsigned char filled_slots, empty_slots;
+
+	filled_slots = mei_hbuf_filled_slots(dev);
+	empty_slots = hw->hbuf_depth - filled_slots;
+
+	/* check for overflow */
+	if (filled_slots > hw->hbuf_depth)
+		return -EOVERFLOW;
+
+	return empty_slots;
+}
+
+/**
+ * mei_me_hbuf_depth - returns depth of the hw buffer.
+ *
+ * @dev: the device structure
+ *
+ * Return: size of hw buffer in slots
+ */
+static u32 mei_me_hbuf_depth(const struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	return hw->hbuf_depth;
+}
+
+/**
+ * mei_me_hbuf_write - writes a message to host hw buffer.
+ *
+ * @dev: the device structure
+ * @hdr: header of message
+ * @hdr_len: header length in bytes: must be multiplication of a slot (4bytes)
+ * @data: payload
+ * @data_len: payload length in bytes
+ *
+ * Return: 0 if success, < 0 - otherwise.
+ */
+static int mei_me_hbuf_write(struct mei_device *dev,
+			     const void *hdr, size_t hdr_len,
+			     const void *data, size_t data_len)
+{
+	unsigned long rem;
+	unsigned long i;
+	const u32 *reg_buf;
+	u32 dw_cnt;
+	int empty_slots;
+
+	if (WARN_ON(!hdr || !data || hdr_len & 0x3))
+		return -EINVAL;
+
+	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
+
+	empty_slots = mei_hbuf_empty_slots(dev);
+	dev_dbg(dev->dev, "empty slots = %hu.\n", empty_slots);
+
+	if (empty_slots < 0)
+		return -EOVERFLOW;
+
+	dw_cnt = mei_data2slots(hdr_len + data_len);
+	if (dw_cnt > (u32)empty_slots)
+		return -EMSGSIZE;
+
+	reg_buf = hdr;
+	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
+		mei_me_hcbww_write(dev, reg_buf[i]);
+
+	reg_buf = data;
+	for (i = 0; i < data_len / MEI_SLOT_SIZE; i++)
+		mei_me_hcbww_write(dev, reg_buf[i]);
+
+	rem = data_len & 0x3;
+	if (rem > 0) {
+		u32 reg = 0;
+
+		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
+		mei_me_hcbww_write(dev, reg);
+	}
+
+	mei_hcsr_set_hig(dev);
+	if (!mei_me_hw_is_ready(dev))
+		return -EIO;
+
+	return 0;
+}
+
+/**
+ * mei_me_count_full_read_slots - counts read full slots.
+ *
+ * @dev: the device structure
+ *
+ * Return: -EOVERFLOW if overflow, otherwise filled slots count
+ */
+static int mei_me_count_full_read_slots(struct mei_device *dev)
+{
+	u32 me_csr;
+	char read_ptr, write_ptr;
+	unsigned char buffer_depth, filled_slots;
+
+	me_csr = mei_me_mecsr_read(dev);
+	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
+	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
+	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
+	filled_slots = (unsigned char) (write_ptr - read_ptr);
+
+	/* check for overflow */
+	if (filled_slots > buffer_depth)
+		return -EOVERFLOW;
+
+	dev_dbg(dev->dev, "filled_slots =%08x\n", filled_slots);
+	return (int)filled_slots;
+}
+
+/**
+ * mei_me_read_slots - reads a message from mei device.
+ *
+ * @dev: the device structure
+ * @buffer: message buffer will be written
+ * @buffer_length: message size will be read
+ *
+ * Return: always 0
+ */
+static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
+			     unsigned long buffer_length)
+{
+	u32 *reg_buf = (u32 *)buffer;
+
+	for (; buffer_length >= MEI_SLOT_SIZE; buffer_length -= MEI_SLOT_SIZE)
+		*reg_buf++ = mei_me_mecbrw_read(dev);
+
+	if (buffer_length > 0) {
+		u32 reg = mei_me_mecbrw_read(dev);
+
+		memcpy(reg_buf, &reg, buffer_length);
+	}
+
+	mei_hcsr_set_hig(dev);
+	return 0;
+}
+
+/**
+ * mei_me_pg_set - write pg enter register
+ *
+ * @dev: the device structure
+ */
+static void mei_me_pg_set(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 reg;
+
+	reg = mei_me_reg_read(hw, H_HPG_CSR);
+	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
+
+	reg |= H_HPG_CSR_PGI;
+
+	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
+	mei_me_reg_write(hw, H_HPG_CSR, reg);
+}
+
+/**
+ * mei_me_pg_unset - write pg exit register
+ *
+ * @dev: the device structure
+ */
+static void mei_me_pg_unset(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 reg;
+
+	reg = mei_me_reg_read(hw, H_HPG_CSR);
+	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
+
+	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
+
+	reg |= H_HPG_CSR_PGIHEXR;
+
+	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
+	mei_me_reg_write(hw, H_HPG_CSR, reg);
+}
+
+/**
+ * mei_me_pg_legacy_enter_sync - perform legacy pg entry procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_pg_legacy_enter_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
+	int ret;
+
+	dev->pg_event = MEI_PG_EVENT_WAIT;
+
+	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
+	if (ret)
+		return ret;
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
+	mutex_lock(&dev->device_lock);
+
+	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
+		mei_me_pg_set(dev);
+		ret = 0;
+	} else {
+		ret = -ETIME;
+	}
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	hw->pg_state = MEI_PG_ON;
+
+	return ret;
+}
+
+/**
+ * mei_me_pg_legacy_exit_sync - perform legacy pg exit procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_pg_legacy_exit_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
+	int ret;
+
+	if (dev->pg_event == MEI_PG_EVENT_RECEIVED)
+		goto reply;
+
+	dev->pg_event = MEI_PG_EVENT_WAIT;
+
+	mei_me_pg_unset(dev);
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
+	mutex_lock(&dev->device_lock);
+
+reply:
+	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
+		ret = -ETIME;
+		goto out;
+	}
+
+	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
+	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD);
+	if (ret)
+		return ret;
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, timeout);
+	mutex_lock(&dev->device_lock);
+
+	if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED)
+		ret = 0;
+	else
+		ret = -ETIME;
+
+out:
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	hw->pg_state = MEI_PG_OFF;
+
+	return ret;
+}
+
+/**
+ * mei_me_pg_in_transition - is device now in pg transition
+ *
+ * @dev: the device structure
+ *
+ * Return: true if in pg transition, false otherwise
+ */
+static bool mei_me_pg_in_transition(struct mei_device *dev)
+{
+	return dev->pg_event >= MEI_PG_EVENT_WAIT &&
+	       dev->pg_event <= MEI_PG_EVENT_INTR_WAIT;
+}
+
+/**
+ * mei_me_pg_is_enabled - detect if PG is supported by HW
+ *
+ * @dev: the device structure
+ *
+ * Return: true is pg supported, false otherwise
+ */
+static bool mei_me_pg_is_enabled(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 reg = mei_me_mecsr_read(dev);
+
+	if (hw->d0i3_supported)
+		return true;
+
+	if ((reg & ME_PGIC_HRA) == 0)
+		goto notsupported;
+
+	if (!dev->hbm_f_pg_supported)
+		goto notsupported;
+
+	return true;
+
+notsupported:
+	dev_dbg(dev->dev, "pg: not supported: d0i3 = %d HGP = %d hbm version %d.%d ?= %d.%d\n",
+		hw->d0i3_supported,
+		!!(reg & ME_PGIC_HRA),
+		dev->version.major_version,
+		dev->version.minor_version,
+		HBM_MAJOR_VERSION_PGI,
+		HBM_MINOR_VERSION_PGI);
+
+	return false;
+}
+
+/**
+ * mei_me_d0i3_set - write d0i3 register bit on mei device.
+ *
+ * @dev: the device structure
+ * @intr: ask for interrupt
+ *
+ * Return: D0I3C register value
+ */
+static u32 mei_me_d0i3_set(struct mei_device *dev, bool intr)
+{
+	u32 reg = mei_me_d0i3c_read(dev);
+
+	reg |= H_D0I3C_I3;
+	if (intr)
+		reg |= H_D0I3C_IR;
+	else
+		reg &= ~H_D0I3C_IR;
+	mei_me_d0i3c_write(dev, reg);
+	/* read it to ensure HW consistency */
+	reg = mei_me_d0i3c_read(dev);
+	return reg;
+}
+
+/**
+ * mei_me_d0i3_unset - clean d0i3 register bit on mei device.
+ *
+ * @dev: the device structure
+ *
+ * Return: D0I3C register value
+ */
+static u32 mei_me_d0i3_unset(struct mei_device *dev)
+{
+	u32 reg = mei_me_d0i3c_read(dev);
+
+	reg &= ~H_D0I3C_I3;
+	reg |= H_D0I3C_IR;
+	mei_me_d0i3c_write(dev, reg);
+	/* read it to ensure HW consistency */
+	reg = mei_me_d0i3c_read(dev);
+	return reg;
+}
+
+/**
+ * mei_me_d0i3_enter_sync - perform d0i3 entry procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_d0i3_enter_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	unsigned long d0i3_timeout = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
+	unsigned long pgi_timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
+	int ret;
+	u32 reg;
+
+	reg = mei_me_d0i3c_read(dev);
+	if (reg & H_D0I3C_I3) {
+		/* we are in d0i3, nothing to do */
+		dev_dbg(dev->dev, "d0i3 set not needed\n");
+		ret = 0;
+		goto on;
+	}
+
+	/* PGI entry procedure */
+	dev->pg_event = MEI_PG_EVENT_WAIT;
+
+	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
+	if (ret)
+		/* FIXME: should we reset here? */
+		goto out;
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_RECEIVED, pgi_timeout);
+	mutex_lock(&dev->device_lock);
+
+	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
+		ret = -ETIME;
+		goto out;
+	}
+	/* end PGI entry procedure */
+
+	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
+
+	reg = mei_me_d0i3_set(dev, true);
+	if (!(reg & H_D0I3C_CIP)) {
+		dev_dbg(dev->dev, "d0i3 enter wait not needed\n");
+		ret = 0;
+		goto on;
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, d0i3_timeout);
+	mutex_lock(&dev->device_lock);
+
+	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
+		reg = mei_me_d0i3c_read(dev);
+		if (!(reg & H_D0I3C_I3)) {
+			ret = -ETIME;
+			goto out;
+		}
+	}
+
+	ret = 0;
+on:
+	hw->pg_state = MEI_PG_ON;
+out:
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev_dbg(dev->dev, "d0i3 enter ret = %d\n", ret);
+	return ret;
+}
+
+/**
+ * mei_me_d0i3_enter - perform d0i3 entry procedure
+ *   no hbm PG handshake
+ *   no waiting for confirmation; runs with interrupts
+ *   disabled
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_d0i3_enter(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 reg;
+
+	reg = mei_me_d0i3c_read(dev);
+	if (reg & H_D0I3C_I3) {
+		/* we are in d0i3, nothing to do */
+		dev_dbg(dev->dev, "already d0i3 : set not needed\n");
+		goto on;
+	}
+
+	mei_me_d0i3_set(dev, false);
+on:
+	hw->pg_state = MEI_PG_ON;
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev_dbg(dev->dev, "d0i3 enter\n");
+	return 0;
+}
+
+/**
+ * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_d0i3_exit_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	unsigned long timeout = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
+	int ret;
+	u32 reg;
+
+	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
+
+	reg = mei_me_d0i3c_read(dev);
+	if (!(reg & H_D0I3C_I3)) {
+		/* we are not in d0i3, nothing to do */
+		dev_dbg(dev->dev, "d0i3 exit not needed\n");
+		ret = 0;
+		goto off;
+	}
+
+	reg = mei_me_d0i3_unset(dev);
+	if (!(reg & H_D0I3C_CIP)) {
+		dev_dbg(dev->dev, "d0i3 exit wait not needed\n");
+		ret = 0;
+		goto off;
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_pg,
+		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, timeout);
+	mutex_lock(&dev->device_lock);
+
+	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
+		reg = mei_me_d0i3c_read(dev);
+		if (reg & H_D0I3C_I3) {
+			ret = -ETIME;
+			goto out;
+		}
+	}
+
+	ret = 0;
+off:
+	hw->pg_state = MEI_PG_OFF;
+out:
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+
+	dev_dbg(dev->dev, "d0i3 exit ret = %d\n", ret);
+	return ret;
+}
+
+/**
+ * mei_me_pg_legacy_intr - perform legacy pg processing
+ *			   in interrupt thread handler
+ *
+ * @dev: the device structure
+ */
+static void mei_me_pg_legacy_intr(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT)
+		return;
+
+	dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
+	hw->pg_state = MEI_PG_OFF;
+	if (waitqueue_active(&dev->wait_pg))
+		wake_up(&dev->wait_pg);
+}
+
+/**
+ * mei_me_d0i3_intr - perform d0i3 processing in interrupt thread handler
+ *
+ * @dev: the device structure
+ * @intr_source: interrupt source
+ */
+static void mei_me_d0i3_intr(struct mei_device *dev, u32 intr_source)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (dev->pg_event == MEI_PG_EVENT_INTR_WAIT &&
+	    (intr_source & H_D0I3C_IS)) {
+		dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
+		if (hw->pg_state == MEI_PG_ON) {
+			hw->pg_state = MEI_PG_OFF;
+			if (dev->hbm_state != MEI_HBM_IDLE) {
+				/*
+				 * force H_RDY because it could be
+				 * wiped off during PG
+				 */
+				dev_dbg(dev->dev, "d0i3 set host ready\n");
+				mei_me_host_set_ready(dev);
+			}
+		} else {
+			hw->pg_state = MEI_PG_ON;
+		}
+
+		wake_up(&dev->wait_pg);
+	}
+
+	if (hw->pg_state == MEI_PG_ON && (intr_source & H_IS)) {
+		/*
+		 * HW sent some data and we are in D0i3, so
+		 * we got here because of HW initiated exit from D0i3.
+		 * Start runtime pm resume sequence to exit low power state.
+		 */
+		dev_dbg(dev->dev, "d0i3 want resume\n");
+		mei_hbm_pg_resume(dev);
+	}
+}
+
+/**
+ * mei_me_pg_intr - perform pg processing in interrupt thread handler
+ *
+ * @dev: the device structure
+ * @intr_source: interrupt source
+ */
+static void mei_me_pg_intr(struct mei_device *dev, u32 intr_source)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (hw->d0i3_supported)
+		mei_me_d0i3_intr(dev, intr_source);
+	else
+		mei_me_pg_legacy_intr(dev);
+}
+
+/**
+ * mei_me_pg_enter_sync - perform runtime pm entry procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+int mei_me_pg_enter_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (hw->d0i3_supported)
+		return mei_me_d0i3_enter_sync(dev);
+	else
+		return mei_me_pg_legacy_enter_sync(dev);
+}
+
+/**
+ * mei_me_pg_exit_sync - perform runtime pm exit procedure
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+int mei_me_pg_exit_sync(struct mei_device *dev)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+
+	if (hw->d0i3_supported)
+		return mei_me_d0i3_exit_sync(dev);
+	else
+		return mei_me_pg_legacy_exit_sync(dev);
+}
+
+/**
+ * mei_me_hw_reset - resets fw via mei csr register.
+ *
+ * @dev: the device structure
+ * @intr_enable: if interrupt should be enabled after reset.
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
+{
+	struct mei_me_hw *hw = to_me_hw(dev);
+	int ret;
+	u32 hcsr;
+
+	if (intr_enable) {
+		mei_me_intr_enable(dev);
+		if (hw->d0i3_supported) {
+			ret = mei_me_d0i3_exit_sync(dev);
+			if (ret)
+				return ret;
+		}
+	}
+
+	pm_runtime_set_active(dev->dev);
+
+	hcsr = mei_hcsr_read(dev);
+	/* H_RST may be found lit before reset is started,
+	 * for example if preceding reset flow hasn't completed.
+	 * In that case asserting H_RST will be ignored, therefore
+	 * we need to clean H_RST bit to start a successful reset sequence.
+	 */
+	if ((hcsr & H_RST) == H_RST) {
+		dev_warn(dev->dev, "H_RST is set = 0x%08X", hcsr);
+		hcsr &= ~H_RST;
+		mei_hcsr_set(dev, hcsr);
+		hcsr = mei_hcsr_read(dev);
+	}
+
+	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
+
+	if (!intr_enable)
+		hcsr &= ~H_CSR_IE_MASK;
+
+	dev->recvd_hw_ready = false;
+	mei_hcsr_write(dev, hcsr);
+
+	/*
+	 * Host reads the H_CSR once to ensure that the
+	 * posted write to H_CSR completes.
+	 */
+	hcsr = mei_hcsr_read(dev);
+
+	if ((hcsr & H_RST) == 0)
+		dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr);
+
+	if ((hcsr & H_RDY) == H_RDY)
+		dev_warn(dev->dev, "H_RDY is not cleared 0x%08X", hcsr);
+
+	if (!intr_enable) {
+		mei_me_hw_reset_release(dev);
+		if (hw->d0i3_supported) {
+			ret = mei_me_d0i3_enter(dev);
+			if (ret)
+				return ret;
+		}
+	}
+	return 0;
+}
+
+/**
+ * mei_me_irq_quick_handler - The ISR of the MEI device
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * Return: irqreturn_t
+ */
+irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
+{
+	struct mei_device *dev = (struct mei_device *)dev_id;
+	u32 hcsr;
+
+	hcsr = mei_hcsr_read(dev);
+	if (!me_intr_src(hcsr))
+		return IRQ_NONE;
+
+	dev_dbg(dev->dev, "interrupt source 0x%08X\n", me_intr_src(hcsr));
+
+	/* disable interrupts on device */
+	me_intr_disable(dev, hcsr);
+	return IRQ_WAKE_THREAD;
+}
+
+/**
+ * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
+ * processing.
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * Return: irqreturn_t
+ *
+ */
+irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
+{
+	struct mei_device *dev = (struct mei_device *) dev_id;
+	struct list_head cmpl_list;
+	s32 slots;
+	u32 hcsr;
+	int rets = 0;
+
+	dev_dbg(dev->dev, "function called after ISR to handle the interrupt processing.\n");
+	/* initialize our complete list */
+	mutex_lock(&dev->device_lock);
+
+	hcsr = mei_hcsr_read(dev);
+	me_intr_clear(dev, hcsr);
+
+	INIT_LIST_HEAD(&cmpl_list);
+
+	/* check if ME wants a reset */
+	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
+		dev_warn(dev->dev, "FW not ready: resetting.\n");
+		schedule_work(&dev->reset_work);
+		goto end;
+	}
+
+	if (mei_me_hw_is_resetting(dev))
+		mei_hcsr_set_hig(dev);
+
+	mei_me_pg_intr(dev, me_intr_src(hcsr));
+
+	/*  check if we need to start the dev */
+	if (!mei_host_is_ready(dev)) {
+		if (mei_hw_is_ready(dev)) {
+			dev_dbg(dev->dev, "we need to start the dev.\n");
+			dev->recvd_hw_ready = true;
+			wake_up(&dev->wait_hw_ready);
+		} else {
+			dev_dbg(dev->dev, "Spurious Interrupt\n");
+		}
+		goto end;
+	}
+	/* check slots available for reading */
+	slots = mei_count_full_read_slots(dev);
+	while (slots > 0) {
+		dev_dbg(dev->dev, "slots to read = %08x\n", slots);
+		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
+		/* There is a race between ME write and interrupt delivery:
+		 * Not all data is always available immediately after the
+		 * interrupt, so try to read again on the next interrupt.
+		 */
+		if (rets == -ENODATA)
+			break;
+
+		if (rets &&
+		    (dev->dev_state != MEI_DEV_RESETTING &&
+		     dev->dev_state != MEI_DEV_POWER_DOWN)) {
+			dev_err(dev->dev, "mei_irq_read_handler ret = %d.\n",
+						rets);
+			schedule_work(&dev->reset_work);
+			goto end;
+		}
+	}
+
+	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
+
+	/*
+	 * During PG handshake only allowed write is the replay to the
+	 * PG exit message, so block calling write function
+	 * if the pg event is in PG handshake
+	 */
+	if (dev->pg_event != MEI_PG_EVENT_WAIT &&
+	    dev->pg_event != MEI_PG_EVENT_RECEIVED) {
+		rets = mei_irq_write_handler(dev, &cmpl_list);
+		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
+	}
+
+	mei_irq_compl_handler(dev, &cmpl_list);
+
+end:
+	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
+	mei_me_intr_enable(dev);
+	mutex_unlock(&dev->device_lock);
+	return IRQ_HANDLED;
+}
+
+static const struct mei_hw_ops mei_me_hw_ops = {
+
+	.trc_status = mei_me_trc_status,
+	.fw_status = mei_me_fw_status,
+	.pg_state  = mei_me_pg_state,
+
+	.host_is_ready = mei_me_host_is_ready,
+
+	.hw_is_ready = mei_me_hw_is_ready,
+	.hw_reset = mei_me_hw_reset,
+	.hw_config = mei_me_hw_config,
+	.hw_start = mei_me_hw_start,
+
+	.pg_in_transition = mei_me_pg_in_transition,
+	.pg_is_enabled = mei_me_pg_is_enabled,
+
+	.intr_clear = mei_me_intr_clear,
+	.intr_enable = mei_me_intr_enable,
+	.intr_disable = mei_me_intr_disable,
+	.synchronize_irq = mei_me_synchronize_irq,
+
+	.hbuf_free_slots = mei_me_hbuf_empty_slots,
+	.hbuf_is_ready = mei_me_hbuf_is_empty,
+	.hbuf_depth = mei_me_hbuf_depth,
+
+	.write = mei_me_hbuf_write,
+
+	.rdbuf_full_slots = mei_me_count_full_read_slots,
+	.read_hdr = mei_me_mecbrw_read,
+	.read = mei_me_read_slots
+};
+
+/**
+ * mei_me_fw_type_nm() - check for nm sku
+ *
+ * Read ME FW Status register to check for the Node Manager (NM) Firmware.
+ * The NM FW is only signaled in PCI function 0.
+ * __Note__: Deprecated by PCH8 and newer.
+ *
+ * @pdev: pci device
+ *
+ * Return: true in case of NM firmware
+ */
+static bool mei_me_fw_type_nm(const struct pci_dev *pdev)
+{
+	u32 reg;
+	unsigned int devfn;
+
+	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
+	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_2, &reg);
+	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_2", PCI_CFG_HFS_2, reg);
+	/* make sure that bit 9 (NM) is up and bit 10 (DM) is down */
+	return (reg & 0x600) == 0x200;
+}
+
+#define MEI_CFG_FW_NM                           \
+	.quirk_probe = mei_me_fw_type_nm
+
+/**
+ * mei_me_fw_sku_sps_4() - check for sps 4.0 sku
+ *
+ * Read ME FW Status register to check for SPS Firmware.
+ * The SPS FW is only signaled in the PCI function 0.
+ * __Note__: Deprecated by SPS 5.0 and newer.
+ *
+ * @pdev: pci device
+ *
+ * Return: true in case of SPS firmware
+ */
+static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
+{
+	u32 reg;
+	unsigned int devfn;
+
+	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
+	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
+	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
+	return (reg & PCI_CFG_HFS_1_OPMODE_MSK) == PCI_CFG_HFS_1_OPMODE_SPS;
+}
+
+#define MEI_CFG_FW_SPS_4                          \
+	.quirk_probe = mei_me_fw_type_sps_4
+
+/**
+ * mei_me_fw_sku_sps() - check for sps sku
+ *
+ * Read ME FW Status register to check for SPS Firmware.
+ * The SPS FW is only signaled in pci function 0
+ *
+ * @pdev: pci device
+ *
+ * Return: true in case of SPS firmware
+ */
+static bool mei_me_fw_type_sps(const struct pci_dev *pdev)
+{
+	u32 reg;
+	u32 fw_type;
+	unsigned int devfn;
+
+	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
+	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_3, &reg);
+	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_3", PCI_CFG_HFS_3, reg);
+	fw_type = (reg & PCI_CFG_HFS_3_FW_SKU_MSK);
+
+	dev_dbg(&pdev->dev, "fw type is %d\n", fw_type);
+
+	return fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
+}
+
+#define MEI_CFG_KIND_ITOUCH                     \
+	.kind = "itouch"
+
+#define MEI_CFG_FW_SPS                          \
+	.quirk_probe = mei_me_fw_type_sps
+
+#define MEI_CFG_FW_VER_SUPP                     \
+	.fw_ver_supported = 1
+
+#define MEI_CFG_ICH_HFS                      \
+	.fw_status.count = 0
+
+#define MEI_CFG_ICH10_HFS                        \
+	.fw_status.count = 1,                   \
+	.fw_status.status[0] = PCI_CFG_HFS_1
+
+#define MEI_CFG_PCH_HFS                         \
+	.fw_status.count = 2,                   \
+	.fw_status.status[0] = PCI_CFG_HFS_1,   \
+	.fw_status.status[1] = PCI_CFG_HFS_2
+
+#define MEI_CFG_PCH8_HFS                        \
+	.fw_status.count = 6,                   \
+	.fw_status.status[0] = PCI_CFG_HFS_1,   \
+	.fw_status.status[1] = PCI_CFG_HFS_2,   \
+	.fw_status.status[2] = PCI_CFG_HFS_3,   \
+	.fw_status.status[3] = PCI_CFG_HFS_4,   \
+	.fw_status.status[4] = PCI_CFG_HFS_5,   \
+	.fw_status.status[5] = PCI_CFG_HFS_6
+
+#define MEI_CFG_DMA_128 \
+	.dma_size[DMA_DSCR_HOST] = SZ_128K, \
+	.dma_size[DMA_DSCR_DEVICE] = SZ_128K, \
+	.dma_size[DMA_DSCR_CTRL] = PAGE_SIZE
+
+#define MEI_CFG_TRC \
+	.hw_trc_supported = 1
+
+/* ICH Legacy devices */
+static const struct mei_cfg mei_me_ich_cfg = {
+	MEI_CFG_ICH_HFS,
+};
+
+/* ICH devices */
+static const struct mei_cfg mei_me_ich10_cfg = {
+	MEI_CFG_ICH10_HFS,
+};
+
+/* PCH6 devices */
+static const struct mei_cfg mei_me_pch6_cfg = {
+	MEI_CFG_PCH_HFS,
+};
+
+/* PCH7 devices */
+static const struct mei_cfg mei_me_pch7_cfg = {
+	MEI_CFG_PCH_HFS,
+	MEI_CFG_FW_VER_SUPP,
+};
+
+/* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */
+static const struct mei_cfg mei_me_pch_cpt_pbg_cfg = {
+	MEI_CFG_PCH_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_FW_NM,
+};
+
+/* PCH8 Lynx Point and newer devices */
+static const struct mei_cfg mei_me_pch8_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+};
+
+/* PCH8 Lynx Point and newer devices - iTouch */
+static const struct mei_cfg mei_me_pch8_itouch_cfg = {
+	MEI_CFG_KIND_ITOUCH,
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+};
+
+/* PCH8 Lynx Point with quirk for SPS Firmware exclusion */
+static const struct mei_cfg mei_me_pch8_sps_4_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_FW_SPS_4,
+};
+
+/* LBG with quirk for SPS (4.0) Firmware exclusion */
+static const struct mei_cfg mei_me_pch12_sps_4_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_FW_SPS_4,
+};
+
+/* Cannon Lake and newer devices */
+static const struct mei_cfg mei_me_pch12_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_DMA_128,
+};
+
+/* Cannon Lake with quirk for SPS 5.0 and newer Firmware exclusion */
+static const struct mei_cfg mei_me_pch12_sps_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_DMA_128,
+	MEI_CFG_FW_SPS,
+};
+
+/* Cannon Lake itouch with quirk for SPS 5.0 and newer Firmware exclusion
+ * w/o DMA support.
+ */
+static const struct mei_cfg mei_me_pch12_itouch_sps_cfg = {
+	MEI_CFG_KIND_ITOUCH,
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_FW_SPS,
+};
+
+/* Tiger Lake and newer devices */
+static const struct mei_cfg mei_me_pch15_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_DMA_128,
+	MEI_CFG_TRC,
+};
+
+/* Tiger Lake with quirk for SPS 5.0 and newer Firmware exclusion */
+static const struct mei_cfg mei_me_pch15_sps_cfg = {
+	MEI_CFG_PCH8_HFS,
+	MEI_CFG_FW_VER_SUPP,
+	MEI_CFG_DMA_128,
+	MEI_CFG_TRC,
+	MEI_CFG_FW_SPS,
+};
+
+/*
+ * mei_cfg_list - A list of platform platform specific configurations.
+ * Note: has to be synchronized with  enum mei_cfg_idx.
+ */
+static const struct mei_cfg *const mei_cfg_list[] = {
+	[MEI_ME_UNDEF_CFG] = NULL,
+	[MEI_ME_ICH_CFG] = &mei_me_ich_cfg,
+	[MEI_ME_ICH10_CFG] = &mei_me_ich10_cfg,
+	[MEI_ME_PCH6_CFG] = &mei_me_pch6_cfg,
+	[MEI_ME_PCH7_CFG] = &mei_me_pch7_cfg,
+	[MEI_ME_PCH_CPT_PBG_CFG] = &mei_me_pch_cpt_pbg_cfg,
+	[MEI_ME_PCH8_CFG] = &mei_me_pch8_cfg,
+	[MEI_ME_PCH8_ITOUCH_CFG] = &mei_me_pch8_itouch_cfg,
+	[MEI_ME_PCH8_SPS_4_CFG] = &mei_me_pch8_sps_4_cfg,
+	[MEI_ME_PCH12_CFG] = &mei_me_pch12_cfg,
+	[MEI_ME_PCH12_SPS_4_CFG] = &mei_me_pch12_sps_4_cfg,
+	[MEI_ME_PCH12_SPS_CFG] = &mei_me_pch12_sps_cfg,
+	[MEI_ME_PCH12_SPS_ITOUCH_CFG] = &mei_me_pch12_itouch_sps_cfg,
+	[MEI_ME_PCH15_CFG] = &mei_me_pch15_cfg,
+	[MEI_ME_PCH15_SPS_CFG] = &mei_me_pch15_sps_cfg,
+};
+
+const struct mei_cfg *mei_me_get_cfg(kernel_ulong_t idx)
+{
+	BUILD_BUG_ON(ARRAY_SIZE(mei_cfg_list) != MEI_ME_NUM_CFG);
+
+	if (idx >= MEI_ME_NUM_CFG)
+		return NULL;
+
+	return mei_cfg_list[idx];
+};
+
+/**
+ * mei_me_dev_init - allocates and initializes the mei device structure
+ *
+ * @parent: device associated with physical device (pci/platform)
+ * @cfg: per device generation config
+ *
+ * Return: The mei_device pointer on success, NULL on failure.
+ */
+struct mei_device *mei_me_dev_init(struct device *parent,
+				   const struct mei_cfg *cfg)
+{
+	struct mei_device *dev;
+	struct mei_me_hw *hw;
+	int i;
+
+	dev = devm_kzalloc(parent, sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	hw = to_me_hw(dev);
+
+	for (i = 0; i < DMA_DSCR_NUM; i++)
+		dev->dr_dscr[i].size = cfg->dma_size[i];
+
+	mei_device_init(dev, parent, &mei_me_hw_ops);
+	hw->cfg = cfg;
+
+	dev->fw_f_fw_ver_supported = cfg->fw_ver_supported;
+
+	dev->kind = cfg->kind;
+
+	return dev;
+}
+
diff --git a/drivers/misc/mei/hw-me.h b/drivers/misc/mei/hw-me.h
new file mode 100644
index 000000000..00a7132ac
--- /dev/null
+++ b/drivers/misc/mei/hw-me.h
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2012-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_INTERFACE_H_
+#define _MEI_INTERFACE_H_
+
+#include <linux/irqreturn.h>
+#include <linux/pci.h>
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "client.h"
+
+/*
+ * mei_cfg - mei device configuration
+ *
+ * @fw_status: FW status
+ * @quirk_probe: device exclusion quirk
+ * @kind: MEI head kind
+ * @dma_size: device DMA buffers size
+ * @fw_ver_supported: is fw version retrievable from FW
+ * @hw_trc_supported: does the hw support trc register
+ */
+struct mei_cfg {
+	const struct mei_fw_status fw_status;
+	bool (*quirk_probe)(const struct pci_dev *pdev);
+	const char *kind;
+	size_t dma_size[DMA_DSCR_NUM];
+	u32 fw_ver_supported:1;
+	u32 hw_trc_supported:1;
+};
+
+
+#define MEI_PCI_DEVICE(dev, cfg) \
+	.vendor = PCI_VENDOR_ID_INTEL, .device = (dev), \
+	.subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID, \
+	.driver_data = (kernel_ulong_t)(cfg),
+
+#define MEI_ME_RPM_TIMEOUT    500 /* ms */
+
+/**
+ * struct mei_me_hw - me hw specific data
+ *
+ * @cfg: per device generation config and ops
+ * @mem_addr: io memory address
+ * @irq: irq number
+ * @pg_state: power gating state
+ * @d0i3_supported: di03 support
+ * @hbuf_depth: depth of hardware host/write buffer in slots
+ * @read_fws: read FW status register handler
+ */
+struct mei_me_hw {
+	const struct mei_cfg *cfg;
+	void __iomem *mem_addr;
+	int irq;
+	enum mei_pg_state pg_state;
+	bool d0i3_supported;
+	u8 hbuf_depth;
+	int (*read_fws)(const struct mei_device *dev, int where, u32 *val);
+};
+
+#define to_me_hw(dev) (struct mei_me_hw *)((dev)->hw)
+
+/**
+ * enum mei_cfg_idx - indices to platform specific configurations.
+ *
+ * Note: has to be synchronized with mei_cfg_list[]
+ *
+ * @MEI_ME_UNDEF_CFG:      Lower sentinel.
+ * @MEI_ME_ICH_CFG:        I/O Controller Hub legacy devices.
+ * @MEI_ME_ICH10_CFG:      I/O Controller Hub platforms Gen10
+ * @MEI_ME_PCH6_CFG:       Platform Controller Hub platforms (Gen6).
+ * @MEI_ME_PCH7_CFG:       Platform Controller Hub platforms (Gen7).
+ * @MEI_ME_PCH_CPT_PBG_CFG:Platform Controller Hub workstations
+ *                         with quirk for Node Manager exclusion.
+ * @MEI_ME_PCH8_CFG:       Platform Controller Hub Gen8 and newer
+ *                         client platforms.
+ * @MEI_ME_PCH8_ITOUCH_CFG:Platform Controller Hub Gen8 and newer
+ *                         client platforms (iTouch).
+ * @MEI_ME_PCH8_SPS_4_CFG: Platform Controller Hub Gen8 and newer
+ *                         servers platforms with quirk for
+ *                         SPS firmware exclusion.
+ * @MEI_ME_PCH12_CFG:      Platform Controller Hub Gen12 and newer
+ * @MEI_ME_PCH12_SPS_4_CFG:Platform Controller Hub Gen12 up to 4.0
+ *                         servers platforms with quirk for
+ *                         SPS firmware exclusion.
+ * @MEI_ME_PCH12_SPS_CFG:  Platform Controller Hub Gen12 5.0 and newer
+ *                         servers platforms with quirk for
+ *                         SPS firmware exclusion.
+ * @MEI_ME_PCH15_CFG:      Platform Controller Hub Gen15 and newer
+ * @MEI_ME_PCH15_SPS_CFG:  Platform Controller Hub Gen15 and newer
+ *                         servers platforms with quirk for
+ *                         SPS firmware exclusion.
+ * @MEI_ME_NUM_CFG:        Upper Sentinel.
+ */
+enum mei_cfg_idx {
+	MEI_ME_UNDEF_CFG,
+	MEI_ME_ICH_CFG,
+	MEI_ME_ICH10_CFG,
+	MEI_ME_PCH6_CFG,
+	MEI_ME_PCH7_CFG,
+	MEI_ME_PCH_CPT_PBG_CFG,
+	MEI_ME_PCH8_CFG,
+	MEI_ME_PCH8_ITOUCH_CFG,
+	MEI_ME_PCH8_SPS_4_CFG,
+	MEI_ME_PCH12_CFG,
+	MEI_ME_PCH12_SPS_4_CFG,
+	MEI_ME_PCH12_SPS_CFG,
+	MEI_ME_PCH12_SPS_ITOUCH_CFG,
+	MEI_ME_PCH15_CFG,
+	MEI_ME_PCH15_SPS_CFG,
+	MEI_ME_NUM_CFG,
+};
+
+const struct mei_cfg *mei_me_get_cfg(kernel_ulong_t idx);
+
+struct mei_device *mei_me_dev_init(struct device *parent,
+				   const struct mei_cfg *cfg);
+
+int mei_me_pg_enter_sync(struct mei_device *dev);
+int mei_me_pg_exit_sync(struct mei_device *dev);
+
+irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id);
+irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id);
+
+#endif /* _MEI_INTERFACE_H_ */
diff --git a/drivers/misc/mei/hw-txe-regs.h b/drivers/misc/mei/hw-txe-regs.h
new file mode 100644
index 000000000..a92b306da
--- /dev/null
+++ b/drivers/misc/mei/hw-txe-regs.h
@@ -0,0 +1,239 @@
+/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
+/*
+ * Copyright (c) 2013-2014, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+#ifndef _MEI_HW_TXE_REGS_H_
+#define _MEI_HW_TXE_REGS_H_
+
+#include "hw.h"
+
+#define SEC_ALIVENESS_TIMER_TIMEOUT        (5 * MSEC_PER_SEC)
+#define SEC_ALIVENESS_WAIT_TIMEOUT         (1 * MSEC_PER_SEC)
+#define SEC_RESET_WAIT_TIMEOUT             (1 * MSEC_PER_SEC)
+#define SEC_READY_WAIT_TIMEOUT             (5 * MSEC_PER_SEC)
+#define START_MESSAGE_RESPONSE_WAIT_TIMEOUT (5 * MSEC_PER_SEC)
+#define RESET_CANCEL_WAIT_TIMEOUT          (1 * MSEC_PER_SEC)
+
+enum {
+	SEC_BAR,
+	BRIDGE_BAR,
+
+	NUM_OF_MEM_BARS
+};
+
+/* SeC FW Status Register
+ *
+ * FW uses this register in order to report its status to host.
+ * This register resides in PCI-E config space.
+ */
+#define PCI_CFG_TXE_FW_STS0   0x40
+#  define PCI_CFG_TXE_FW_STS0_WRK_ST_MSK    0x0000000F
+#  define PCI_CFG_TXE_FW_STS0_OP_ST_MSK     0x000001C0
+#  define PCI_CFG_TXE_FW_STS0_FW_INIT_CMPLT 0x00000200
+#  define PCI_CFG_TXE_FW_STS0_ERR_CODE_MSK  0x0000F000
+#  define PCI_CFG_TXE_FW_STS0_OP_MODE_MSK   0x000F0000
+#  define PCI_CFG_TXE_FW_STS0_RST_CNT_MSK   0x00F00000
+#define PCI_CFG_TXE_FW_STS1   0x48
+
+#define IPC_BASE_ADDR	0x80400 /* SeC IPC Base Address */
+
+/* IPC Input Doorbell Register */
+#define SEC_IPC_INPUT_DOORBELL_REG       (0x0000 + IPC_BASE_ADDR)
+
+/* IPC Input Status Register
+ * This register indicates whether or not processing of
+ * the most recent command has been completed by the SEC
+ * New commands and payloads should not be written by the Host
+ * until this indicates that the previous command has been processed.
+ */
+#define SEC_IPC_INPUT_STATUS_REG         (0x0008 + IPC_BASE_ADDR)
+#  define SEC_IPC_INPUT_STATUS_RDY    BIT(0)
+
+/* IPC Host Interrupt Status Register */
+#define SEC_IPC_HOST_INT_STATUS_REG      (0x0010 + IPC_BASE_ADDR)
+#define   SEC_IPC_HOST_INT_STATUS_OUT_DB             BIT(0)
+#define   SEC_IPC_HOST_INT_STATUS_IN_RDY             BIT(1)
+#define   SEC_IPC_HOST_INT_STATUS_HDCP_M0_RCVD       BIT(5)
+#define   SEC_IPC_HOST_INT_STATUS_ILL_MEM_ACCESS     BIT(17)
+#define   SEC_IPC_HOST_INT_STATUS_AES_HKEY_ERR       BIT(18)
+#define   SEC_IPC_HOST_INT_STATUS_DES_HKEY_ERR       BIT(19)
+#define   SEC_IPC_HOST_INT_STATUS_TMRMTB_OVERFLOW    BIT(21)
+
+/* Convenient mask for pending interrupts */
+#define   SEC_IPC_HOST_INT_STATUS_PENDING \
+		(SEC_IPC_HOST_INT_STATUS_OUT_DB| \
+		SEC_IPC_HOST_INT_STATUS_IN_RDY)
+
+/* IPC Host Interrupt Mask Register */
+#define SEC_IPC_HOST_INT_MASK_REG        (0x0014 + IPC_BASE_ADDR)
+
+#  define SEC_IPC_HOST_INT_MASK_OUT_DB	BIT(0) /* Output Doorbell Int Mask */
+#  define SEC_IPC_HOST_INT_MASK_IN_RDY	BIT(1) /* Input Ready Int Mask */
+
+/* IPC Input Payload RAM */
+#define SEC_IPC_INPUT_PAYLOAD_REG        (0x0100 + IPC_BASE_ADDR)
+/* IPC Shared Payload RAM */
+#define IPC_SHARED_PAYLOAD_REG           (0x0200 + IPC_BASE_ADDR)
+
+/* SeC Address Translation Table Entry 2 - Ctrl
+ *
+ * This register resides also in SeC's PCI-E Memory space.
+ */
+#define SATT2_CTRL_REG                   0x1040
+#  define SATT2_CTRL_VALID_MSK            BIT(0)
+#  define SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT 8
+#  define SATT2_CTRL_BRIDGE_HOST_EN_MSK   BIT(12)
+
+/* SATT Table Entry 2 SAP Base Address Register */
+#define SATT2_SAP_BA_REG                 0x1044
+/* SATT Table Entry 2 SAP Size Register. */
+#define SATT2_SAP_SIZE_REG               0x1048
+ /* SATT Table Entry 2 SAP Bridge Address - LSB Register */
+#define SATT2_BRG_BA_LSB_REG             0x104C
+
+/* Host High-level Interrupt Status Register */
+#define HHISR_REG                        0x2020
+/* Host High-level Interrupt Enable Register
+ *
+ * Resides in PCI memory space. This is the top hierarchy for
+ * interrupts from SeC to host, aggregating both interrupts that
+ * arrive through HICR registers as well as interrupts
+ * that arrive via IPC.
+ */
+#define HHIER_REG                        0x2024
+#define   IPC_HHIER_SEC	BIT(0)
+#define   IPC_HHIER_BRIDGE	BIT(1)
+#define   IPC_HHIER_MSK	(IPC_HHIER_SEC | IPC_HHIER_BRIDGE)
+
+/* Host High-level Interrupt Mask Register.
+ *
+ * Resides in PCI memory space.
+ * This is the top hierarchy for masking interrupts from SeC to host.
+ */
+#define HHIMR_REG                        0x2028
+#define   IPC_HHIMR_SEC       BIT(0)
+#define   IPC_HHIMR_BRIDGE    BIT(1)
+
+/* Host High-level IRQ Status Register */
+#define HHIRQSR_REG                      0x202C
+
+/* Host Interrupt Cause Register 0 - SeC IPC Readiness
+ *
+ * This register is both an ICR to Host from PCI Memory Space
+ * and it is also exposed in the SeC memory space.
+ * This register is used by SeC's IPC driver in order
+ * to synchronize with host about IPC interface state.
+ */
+#define HICR_SEC_IPC_READINESS_REG       0x2040
+#define   HICR_SEC_IPC_READINESS_HOST_RDY  BIT(0)
+#define   HICR_SEC_IPC_READINESS_SEC_RDY   BIT(1)
+#define   HICR_SEC_IPC_READINESS_SYS_RDY     \
+	  (HICR_SEC_IPC_READINESS_HOST_RDY | \
+	   HICR_SEC_IPC_READINESS_SEC_RDY)
+#define   HICR_SEC_IPC_READINESS_RDY_CLR   BIT(2)
+
+/* Host Interrupt Cause Register 1 - Aliveness Response */
+/* This register is both an ICR to Host from PCI Memory Space
+ * and it is also exposed in the SeC memory space.
+ * The register may be used by SeC to ACK a host request for aliveness.
+ */
+#define HICR_HOST_ALIVENESS_RESP_REG     0x2044
+#define   HICR_HOST_ALIVENESS_RESP_ACK    BIT(0)
+
+/* Host Interrupt Cause Register 2 - SeC IPC Output Doorbell */
+#define HICR_SEC_IPC_OUTPUT_DOORBELL_REG 0x2048
+
+/* Host Interrupt Status Register.
+ *
+ * Resides in PCI memory space.
+ * This is the main register involved in generating interrupts
+ * from SeC to host via HICRs.
+ * The interrupt generation rules are as follows:
+ * An interrupt will be generated whenever for any i,
+ * there is a transition from a state where at least one of
+ * the following conditions did not hold, to a state where
+ * ALL the following conditions hold:
+ * A) HISR.INT[i]_STS == 1.
+ * B) HIER.INT[i]_EN == 1.
+ */
+#define HISR_REG                         0x2060
+#define   HISR_INT_0_STS      BIT(0)
+#define   HISR_INT_1_STS      BIT(1)
+#define   HISR_INT_2_STS      BIT(2)
+#define   HISR_INT_3_STS      BIT(3)
+#define   HISR_INT_4_STS      BIT(4)
+#define   HISR_INT_5_STS      BIT(5)
+#define   HISR_INT_6_STS      BIT(6)
+#define   HISR_INT_7_STS      BIT(7)
+#define   HISR_INT_STS_MSK \
+	(HISR_INT_0_STS | HISR_INT_1_STS | HISR_INT_2_STS)
+
+/* Host Interrupt Enable Register. Resides in PCI memory space. */
+#define HIER_REG                         0x2064
+#define   HIER_INT_0_EN      BIT(0)
+#define   HIER_INT_1_EN      BIT(1)
+#define   HIER_INT_2_EN      BIT(2)
+#define   HIER_INT_3_EN      BIT(3)
+#define   HIER_INT_4_EN      BIT(4)
+#define   HIER_INT_5_EN      BIT(5)
+#define   HIER_INT_6_EN      BIT(6)
+#define   HIER_INT_7_EN      BIT(7)
+
+#define   HIER_INT_EN_MSK \
+	 (HIER_INT_0_EN | HIER_INT_1_EN | HIER_INT_2_EN)
+
+
+/* SEC Memory Space IPC output payload.
+ *
+ * This register is part of the output payload which SEC provides to host.
+ */
+#define BRIDGE_IPC_OUTPUT_PAYLOAD_REG    0x20C0
+
+/* SeC Interrupt Cause Register - Host Aliveness Request
+ * This register is both an ICR to SeC and it is also exposed
+ * in the host-visible PCI memory space.
+ * The register is used by host to request SeC aliveness.
+ */
+#define SICR_HOST_ALIVENESS_REQ_REG      0x214C
+#define   SICR_HOST_ALIVENESS_REQ_REQUESTED    BIT(0)
+
+
+/* SeC Interrupt Cause Register - Host IPC Readiness
+ *
+ * This register is both an ICR to SeC and it is also exposed
+ * in the host-visible PCI memory space.
+ * This register is used by the host's SeC driver uses in order
+ * to synchronize with SeC about IPC interface state.
+ */
+#define SICR_HOST_IPC_READINESS_REQ_REG  0x2150
+
+
+#define SICR_HOST_IPC_READINESS_HOST_RDY  BIT(0)
+#define SICR_HOST_IPC_READINESS_SEC_RDY   BIT(1)
+#define SICR_HOST_IPC_READINESS_SYS_RDY     \
+	(SICR_HOST_IPC_READINESS_HOST_RDY | \
+	 SICR_HOST_IPC_READINESS_SEC_RDY)
+#define SICR_HOST_IPC_READINESS_RDY_CLR   BIT(2)
+
+/* SeC Interrupt Cause Register - SeC IPC Output Status
+ *
+ * This register indicates whether or not processing of the most recent
+ * command has been completed by the Host.
+ * New commands and payloads should not be written by SeC until this
+ * register indicates that the previous command has been processed.
+ */
+#define SICR_SEC_IPC_OUTPUT_STATUS_REG   0x2154
+#  define SEC_IPC_OUTPUT_STATUS_RDY BIT(0)
+
+
+
+/*  MEI IPC Message payload size 64 bytes */
+#define PAYLOAD_SIZE        64
+
+/* MAX size for SATT range 32MB */
+#define SATT_RANGE_MAX     (32 << 20)
+
+
+#endif /* _MEI_HW_TXE_REGS_H_ */
+
diff --git a/drivers/misc/mei/hw-txe.c b/drivers/misc/mei/hw-txe.c
new file mode 100644
index 000000000..a4e854b9b
--- /dev/null
+++ b/drivers/misc/mei/hw-txe.c
@@ -0,0 +1,1260 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2013-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/pci.h>
+#include <linux/jiffies.h>
+#include <linux/ktime.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hw-txe.h"
+#include "client.h"
+#include "hbm.h"
+
+#include "mei-trace.h"
+
+#define TXE_HBUF_DEPTH (PAYLOAD_SIZE / MEI_SLOT_SIZE)
+
+/**
+ * mei_txe_reg_read - Reads 32bit data from the txe device
+ *
+ * @base_addr: registers base address
+ * @offset: register offset
+ *
+ * Return: register value
+ */
+static inline u32 mei_txe_reg_read(void __iomem *base_addr,
+					unsigned long offset)
+{
+	return ioread32(base_addr + offset);
+}
+
+/**
+ * mei_txe_reg_write - Writes 32bit data to the txe device
+ *
+ * @base_addr: registers base address
+ * @offset: register offset
+ * @value: the value to write
+ */
+static inline void mei_txe_reg_write(void __iomem *base_addr,
+				unsigned long offset, u32 value)
+{
+	iowrite32(value, base_addr + offset);
+}
+
+/**
+ * mei_txe_sec_reg_read_silent - Reads 32bit data from the SeC BAR
+ *
+ * @hw: the txe hardware structure
+ * @offset: register offset
+ *
+ * Doesn't check for aliveness while Reads 32bit data from the SeC BAR
+ *
+ * Return: register value
+ */
+static inline u32 mei_txe_sec_reg_read_silent(struct mei_txe_hw *hw,
+				unsigned long offset)
+{
+	return mei_txe_reg_read(hw->mem_addr[SEC_BAR], offset);
+}
+
+/**
+ * mei_txe_sec_reg_read - Reads 32bit data from the SeC BAR
+ *
+ * @hw: the txe hardware structure
+ * @offset: register offset
+ *
+ * Reads 32bit data from the SeC BAR and shout loud if aliveness is not set
+ *
+ * Return: register value
+ */
+static inline u32 mei_txe_sec_reg_read(struct mei_txe_hw *hw,
+				unsigned long offset)
+{
+	WARN(!hw->aliveness, "sec read: aliveness not asserted\n");
+	return mei_txe_sec_reg_read_silent(hw, offset);
+}
+/**
+ * mei_txe_sec_reg_write_silent - Writes 32bit data to the SeC BAR
+ *   doesn't check for aliveness
+ *
+ * @hw: the txe hardware structure
+ * @offset: register offset
+ * @value: value to write
+ *
+ * Doesn't check for aliveness while writes 32bit data from to the SeC BAR
+ */
+static inline void mei_txe_sec_reg_write_silent(struct mei_txe_hw *hw,
+				unsigned long offset, u32 value)
+{
+	mei_txe_reg_write(hw->mem_addr[SEC_BAR], offset, value);
+}
+
+/**
+ * mei_txe_sec_reg_write - Writes 32bit data to the SeC BAR
+ *
+ * @hw: the txe hardware structure
+ * @offset: register offset
+ * @value: value to write
+ *
+ * Writes 32bit data from the SeC BAR and shout loud if aliveness is not set
+ */
+static inline void mei_txe_sec_reg_write(struct mei_txe_hw *hw,
+				unsigned long offset, u32 value)
+{
+	WARN(!hw->aliveness, "sec write: aliveness not asserted\n");
+	mei_txe_sec_reg_write_silent(hw, offset, value);
+}
+/**
+ * mei_txe_br_reg_read - Reads 32bit data from the Bridge BAR
+ *
+ * @hw: the txe hardware structure
+ * @offset: offset from which to read the data
+ *
+ * Return: the byte read.
+ */
+static inline u32 mei_txe_br_reg_read(struct mei_txe_hw *hw,
+				unsigned long offset)
+{
+	return mei_txe_reg_read(hw->mem_addr[BRIDGE_BAR], offset);
+}
+
+/**
+ * mei_txe_br_reg_write - Writes 32bit data to the Bridge BAR
+ *
+ * @hw: the txe hardware structure
+ * @offset: offset from which to write the data
+ * @value: the byte to write
+ */
+static inline void mei_txe_br_reg_write(struct mei_txe_hw *hw,
+				unsigned long offset, u32 value)
+{
+	mei_txe_reg_write(hw->mem_addr[BRIDGE_BAR], offset, value);
+}
+
+/**
+ * mei_txe_aliveness_set - request for aliveness change
+ *
+ * @dev: the device structure
+ * @req: requested aliveness value
+ *
+ * Request for aliveness change and returns true if the change is
+ *   really needed and false if aliveness is already
+ *   in the requested state
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: true if request was send
+ */
+static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
+{
+
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	bool do_req = hw->aliveness != req;
+
+	dev_dbg(dev->dev, "Aliveness current=%d request=%d\n",
+				hw->aliveness, req);
+	if (do_req) {
+		dev->pg_event = MEI_PG_EVENT_WAIT;
+		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
+	}
+	return do_req;
+}
+
+
+/**
+ * mei_txe_aliveness_req_get - get aliveness requested register value
+ *
+ * @dev: the device structure
+ *
+ * Extract HICR_HOST_ALIVENESS_RESP_ACK bit from
+ * from HICR_HOST_ALIVENESS_REQ register value
+ *
+ * Return: SICR_HOST_ALIVENESS_REQ_REQUESTED bit value
+ */
+static u32 mei_txe_aliveness_req_get(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 reg;
+
+	reg = mei_txe_br_reg_read(hw, SICR_HOST_ALIVENESS_REQ_REG);
+	return reg & SICR_HOST_ALIVENESS_REQ_REQUESTED;
+}
+
+/**
+ * mei_txe_aliveness_get - get aliveness response register value
+ *
+ * @dev: the device structure
+ *
+ * Return: HICR_HOST_ALIVENESS_RESP_ACK bit from HICR_HOST_ALIVENESS_RESP
+ *         register
+ */
+static u32 mei_txe_aliveness_get(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 reg;
+
+	reg = mei_txe_br_reg_read(hw, HICR_HOST_ALIVENESS_RESP_REG);
+	return reg & HICR_HOST_ALIVENESS_RESP_ACK;
+}
+
+/**
+ * mei_txe_aliveness_poll - waits for aliveness to settle
+ *
+ * @dev: the device structure
+ * @expected: expected aliveness value
+ *
+ * Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
+ *
+ * Return: 0 if the expected value was received, -ETIME otherwise
+ */
+static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	ktime_t stop, start;
+
+	start = ktime_get();
+	stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
+	do {
+		hw->aliveness = mei_txe_aliveness_get(dev);
+		if (hw->aliveness == expected) {
+			dev->pg_event = MEI_PG_EVENT_IDLE;
+			dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
+				ktime_to_us(ktime_sub(ktime_get(), start)));
+			return 0;
+		}
+		usleep_range(20, 50);
+	} while (ktime_before(ktime_get(), stop));
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev_err(dev->dev, "aliveness timed out\n");
+	return -ETIME;
+}
+
+/**
+ * mei_txe_aliveness_wait - waits for aliveness to settle
+ *
+ * @dev: the device structure
+ * @expected: expected aliveness value
+ *
+ * Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
+ *
+ * Return: 0 on success and < 0 otherwise
+ */
+static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	const unsigned long timeout =
+			msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
+	long err;
+	int ret;
+
+	hw->aliveness = mei_txe_aliveness_get(dev);
+	if (hw->aliveness == expected)
+		return 0;
+
+	mutex_unlock(&dev->device_lock);
+	err = wait_event_timeout(hw->wait_aliveness_resp,
+			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
+	mutex_lock(&dev->device_lock);
+
+	hw->aliveness = mei_txe_aliveness_get(dev);
+	ret = hw->aliveness == expected ? 0 : -ETIME;
+
+	if (ret)
+		dev_warn(dev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
+			err, hw->aliveness, dev->pg_event);
+	else
+		dev_dbg(dev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
+			jiffies_to_msecs(timeout - err),
+			hw->aliveness, dev->pg_event);
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	return ret;
+}
+
+/**
+ * mei_txe_aliveness_set_sync - sets an wait for aliveness to complete
+ *
+ * @dev: the device structure
+ * @req: requested aliveness value
+ *
+ * Return: 0 on success and < 0 otherwise
+ */
+int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req)
+{
+	if (mei_txe_aliveness_set(dev, req))
+		return mei_txe_aliveness_wait(dev, req);
+	return 0;
+}
+
+/**
+ * mei_txe_pg_in_transition - is device now in pg transition
+ *
+ * @dev: the device structure
+ *
+ * Return: true if in pg transition, false otherwise
+ */
+static bool mei_txe_pg_in_transition(struct mei_device *dev)
+{
+	return dev->pg_event == MEI_PG_EVENT_WAIT;
+}
+
+/**
+ * mei_txe_pg_is_enabled - detect if PG is supported by HW
+ *
+ * @dev: the device structure
+ *
+ * Return: true is pg supported, false otherwise
+ */
+static bool mei_txe_pg_is_enabled(struct mei_device *dev)
+{
+	return true;
+}
+
+/**
+ * mei_txe_pg_state  - translate aliveness register value
+ *   to the mei power gating state
+ *
+ * @dev: the device structure
+ *
+ * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
+ */
+static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
+}
+
+/**
+ * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_input_ready_interrupt_enable(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 hintmsk;
+	/* Enable the SEC_IPC_HOST_INT_MASK_IN_RDY interrupt */
+	hintmsk = mei_txe_sec_reg_read(hw, SEC_IPC_HOST_INT_MASK_REG);
+	hintmsk |= SEC_IPC_HOST_INT_MASK_IN_RDY;
+	mei_txe_sec_reg_write(hw, SEC_IPC_HOST_INT_MASK_REG, hintmsk);
+}
+
+/**
+ * mei_txe_input_doorbell_set - sets bit 0 in
+ *    SEC_IPC_INPUT_DOORBELL.IPC_INPUT_DOORBELL.
+ *
+ * @hw: the txe hardware structure
+ */
+static void mei_txe_input_doorbell_set(struct mei_txe_hw *hw)
+{
+	/* Clear the interrupt cause */
+	clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause);
+	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_DOORBELL_REG, 1);
+}
+
+/**
+ * mei_txe_output_ready_set - Sets the SICR_SEC_IPC_OUTPUT_STATUS bit to 1
+ *
+ * @hw: the txe hardware structure
+ */
+static void mei_txe_output_ready_set(struct mei_txe_hw *hw)
+{
+	mei_txe_br_reg_write(hw,
+			SICR_SEC_IPC_OUTPUT_STATUS_REG,
+			SEC_IPC_OUTPUT_STATUS_RDY);
+}
+
+/**
+ * mei_txe_is_input_ready - check if TXE is ready for receiving data
+ *
+ * @dev: the device structure
+ *
+ * Return: true if INPUT STATUS READY bit is set
+ */
+static bool mei_txe_is_input_ready(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 status;
+
+	status = mei_txe_sec_reg_read(hw, SEC_IPC_INPUT_STATUS_REG);
+	return !!(SEC_IPC_INPUT_STATUS_RDY & status);
+}
+
+/**
+ * mei_txe_intr_clear - clear all interrupts
+ *
+ * @dev: the device structure
+ */
+static inline void mei_txe_intr_clear(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_sec_reg_write_silent(hw, SEC_IPC_HOST_INT_STATUS_REG,
+		SEC_IPC_HOST_INT_STATUS_PENDING);
+	mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_STS_MSK);
+	mei_txe_br_reg_write(hw, HHISR_REG, IPC_HHIER_MSK);
+}
+
+/**
+ * mei_txe_intr_disable - disable all interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_intr_disable(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_br_reg_write(hw, HHIER_REG, 0);
+	mei_txe_br_reg_write(hw, HIER_REG, 0);
+}
+/**
+ * mei_txe_intr_enable - enable all interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_intr_enable(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_br_reg_write(hw, HHIER_REG, IPC_HHIER_MSK);
+	mei_txe_br_reg_write(hw, HIER_REG, HIER_INT_EN_MSK);
+}
+
+/**
+ * mei_txe_synchronize_irq - wait for pending IRQ handlers
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_synchronize_irq(struct mei_device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	synchronize_irq(pdev->irq);
+}
+
+/**
+ * mei_txe_pending_interrupts - check if there are pending interrupts
+ *	only Aliveness, Input ready, and output doorbell are of relevance
+ *
+ * @dev: the device structure
+ *
+ * Checks if there are pending interrupts
+ * only Aliveness, Readiness, Input ready, and Output doorbell are relevant
+ *
+ * Return: true if there are pending interrupts
+ */
+static bool mei_txe_pending_interrupts(struct mei_device *dev)
+{
+
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	bool ret = (hw->intr_cause & (TXE_INTR_READINESS |
+				      TXE_INTR_ALIVENESS |
+				      TXE_INTR_IN_READY  |
+				      TXE_INTR_OUT_DB));
+
+	if (ret) {
+		dev_dbg(dev->dev,
+			"Pending Interrupts InReady=%01d Readiness=%01d, Aliveness=%01d, OutDoor=%01d\n",
+			!!(hw->intr_cause & TXE_INTR_IN_READY),
+			!!(hw->intr_cause & TXE_INTR_READINESS),
+			!!(hw->intr_cause & TXE_INTR_ALIVENESS),
+			!!(hw->intr_cause & TXE_INTR_OUT_DB));
+	}
+	return ret;
+}
+
+/**
+ * mei_txe_input_payload_write - write a dword to the host buffer
+ *	at offset idx
+ *
+ * @dev: the device structure
+ * @idx: index in the host buffer
+ * @value: value
+ */
+static void mei_txe_input_payload_write(struct mei_device *dev,
+			unsigned long idx, u32 value)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_PAYLOAD_REG +
+			(idx * sizeof(u32)), value);
+}
+
+/**
+ * mei_txe_out_data_read - read dword from the device buffer
+ *	at offset idx
+ *
+ * @dev: the device structure
+ * @idx: index in the device buffer
+ *
+ * Return: register value at index
+ */
+static u32 mei_txe_out_data_read(const struct mei_device *dev,
+					unsigned long idx)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	return mei_txe_br_reg_read(hw,
+		BRIDGE_IPC_OUTPUT_PAYLOAD_REG + (idx * sizeof(u32)));
+}
+
+/* Readiness */
+
+/**
+ * mei_txe_readiness_set_host_rdy - set host readiness bit
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_readiness_set_host_rdy(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_br_reg_write(hw,
+		SICR_HOST_IPC_READINESS_REQ_REG,
+		SICR_HOST_IPC_READINESS_HOST_RDY);
+}
+
+/**
+ * mei_txe_readiness_clear - clear host readiness bit
+ *
+ * @dev: the device structure
+ */
+static void mei_txe_readiness_clear(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	mei_txe_br_reg_write(hw, SICR_HOST_IPC_READINESS_REQ_REG,
+				SICR_HOST_IPC_READINESS_RDY_CLR);
+}
+/**
+ * mei_txe_readiness_get - Reads and returns
+ *	the HICR_SEC_IPC_READINESS register value
+ *
+ * @dev: the device structure
+ *
+ * Return: the HICR_SEC_IPC_READINESS register value
+ */
+static u32 mei_txe_readiness_get(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	return mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
+}
+
+
+/**
+ * mei_txe_readiness_is_sec_rdy - check readiness
+ *  for HICR_SEC_IPC_READINESS_SEC_RDY
+ *
+ * @readiness: cached readiness state
+ *
+ * Return: true if readiness bit is set
+ */
+static inline bool mei_txe_readiness_is_sec_rdy(u32 readiness)
+{
+	return !!(readiness & HICR_SEC_IPC_READINESS_SEC_RDY);
+}
+
+/**
+ * mei_txe_hw_is_ready - check if the hw is ready
+ *
+ * @dev: the device structure
+ *
+ * Return: true if sec is ready
+ */
+static bool mei_txe_hw_is_ready(struct mei_device *dev)
+{
+	u32 readiness =  mei_txe_readiness_get(dev);
+
+	return mei_txe_readiness_is_sec_rdy(readiness);
+}
+
+/**
+ * mei_txe_host_is_ready - check if the host is ready
+ *
+ * @dev: the device structure
+ *
+ * Return: true if host is ready
+ */
+static inline bool mei_txe_host_is_ready(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 reg = mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
+
+	return !!(reg & HICR_SEC_IPC_READINESS_HOST_RDY);
+}
+
+/**
+ * mei_txe_readiness_wait - wait till readiness settles
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and -ETIME on timeout
+ */
+static int mei_txe_readiness_wait(struct mei_device *dev)
+{
+	if (mei_txe_hw_is_ready(dev))
+		return 0;
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready,
+			msecs_to_jiffies(SEC_RESET_WAIT_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+	if (!dev->recvd_hw_ready) {
+		dev_err(dev->dev, "wait for readiness failed\n");
+		return -ETIME;
+	}
+
+	dev->recvd_hw_ready = false;
+	return 0;
+}
+
+static const struct mei_fw_status mei_txe_fw_sts = {
+	.count = 2,
+	.status[0] = PCI_CFG_TXE_FW_STS0,
+	.status[1] = PCI_CFG_TXE_FW_STS1
+};
+
+/**
+ * mei_txe_fw_status - read fw status register from pci config space
+ *
+ * @dev: mei device
+ * @fw_status: fw status register values
+ *
+ * Return: 0 on success, error otherwise
+ */
+static int mei_txe_fw_status(struct mei_device *dev,
+			     struct mei_fw_status *fw_status)
+{
+	const struct mei_fw_status *fw_src = &mei_txe_fw_sts;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	int ret;
+	int i;
+
+	if (!fw_status)
+		return -EINVAL;
+
+	fw_status->count = fw_src->count;
+	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
+		ret = pci_read_config_dword(pdev, fw_src->status[i],
+					    &fw_status->status[i]);
+		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HSF_X",
+				       fw_src->status[i],
+				       fw_status->status[i]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_txe_hw_config - configure hardware at the start of the devices
+ *
+ * @dev: the device structure
+ *
+ * Configure hardware at the start of the device should be done only
+ *   once at the device probe time
+ *
+ * Return: always 0
+ */
+static int mei_txe_hw_config(struct mei_device *dev)
+{
+
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	hw->aliveness = mei_txe_aliveness_get(dev);
+	hw->readiness = mei_txe_readiness_get(dev);
+
+	dev_dbg(dev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
+		hw->aliveness, hw->readiness);
+
+	return 0;
+}
+
+/**
+ * mei_txe_write - writes a message to device.
+ *
+ * @dev: the device structure
+ * @hdr: header of message
+ * @hdr_len: header length in bytes - must multiplication of a slot (4bytes)
+ * @data: payload
+ * @data_len: paylead length in bytes
+ *
+ * Return: 0 if success, < 0 - otherwise.
+ */
+static int mei_txe_write(struct mei_device *dev,
+			 const void *hdr, size_t hdr_len,
+			 const void *data, size_t data_len)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	unsigned long rem;
+	const u32 *reg_buf;
+	u32 slots = TXE_HBUF_DEPTH;
+	u32 dw_cnt;
+	unsigned long i, j;
+
+	if (WARN_ON(!hdr || !data || hdr_len & 0x3))
+		return -EINVAL;
+
+	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
+
+	dw_cnt = mei_data2slots(hdr_len + data_len);
+	if (dw_cnt > slots)
+		return -EMSGSIZE;
+
+	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
+		return -EAGAIN;
+
+	/* Enable Input Ready Interrupt. */
+	mei_txe_input_ready_interrupt_enable(dev);
+
+	if (!mei_txe_is_input_ready(dev)) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		dev_err(dev->dev, "Input is not ready %s\n", fw_sts_str);
+		return -EAGAIN;
+	}
+
+	reg_buf = hdr;
+	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
+		mei_txe_input_payload_write(dev, i, reg_buf[i]);
+
+	reg_buf = data;
+	for (j = 0; j < data_len / MEI_SLOT_SIZE; j++)
+		mei_txe_input_payload_write(dev, i + j, reg_buf[j]);
+
+	rem = data_len & 0x3;
+	if (rem > 0) {
+		u32 reg = 0;
+
+		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
+		mei_txe_input_payload_write(dev, i + j, reg);
+	}
+
+	/* after each write the whole buffer is consumed */
+	hw->slots = 0;
+
+	/* Set Input-Doorbell */
+	mei_txe_input_doorbell_set(hw);
+
+	return 0;
+}
+
+/**
+ * mei_txe_hbuf_depth - mimics the me hbuf circular buffer
+ *
+ * @dev: the device structure
+ *
+ * Return: the TXE_HBUF_DEPTH
+ */
+static u32 mei_txe_hbuf_depth(const struct mei_device *dev)
+{
+	return TXE_HBUF_DEPTH;
+}
+
+/**
+ * mei_txe_hbuf_empty_slots - mimics the me hbuf circular buffer
+ *
+ * @dev: the device structure
+ *
+ * Return: always TXE_HBUF_DEPTH
+ */
+static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	return hw->slots;
+}
+
+/**
+ * mei_txe_count_full_read_slots - mimics the me device circular buffer
+ *
+ * @dev: the device structure
+ *
+ * Return: always buffer size in dwords count
+ */
+static int mei_txe_count_full_read_slots(struct mei_device *dev)
+{
+	/* read buffers has static size */
+	return TXE_HBUF_DEPTH;
+}
+
+/**
+ * mei_txe_read_hdr - read message header which is always in 4 first bytes
+ *
+ * @dev: the device structure
+ *
+ * Return: mei message header
+ */
+
+static u32 mei_txe_read_hdr(const struct mei_device *dev)
+{
+	return mei_txe_out_data_read(dev, 0);
+}
+/**
+ * mei_txe_read - reads a message from the txe device.
+ *
+ * @dev: the device structure
+ * @buf: message buffer will be written
+ * @len: message size will be read
+ *
+ * Return: -EINVAL on error wrong argument and 0 on success
+ */
+static int mei_txe_read(struct mei_device *dev,
+		unsigned char *buf, unsigned long len)
+{
+
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 *reg_buf, reg;
+	u32 rem;
+	u32 i;
+
+	if (WARN_ON(!buf || !len))
+		return -EINVAL;
+
+	reg_buf = (u32 *)buf;
+	rem = len & 0x3;
+
+	dev_dbg(dev->dev, "buffer-length = %lu buf[0]0x%08X\n",
+		len, mei_txe_out_data_read(dev, 0));
+
+	for (i = 0; i < len / MEI_SLOT_SIZE; i++) {
+		/* skip header: index starts from 1 */
+		reg = mei_txe_out_data_read(dev, i + 1);
+		dev_dbg(dev->dev, "buf[%d] = 0x%08X\n", i, reg);
+		*reg_buf++ = reg;
+	}
+
+	if (rem) {
+		reg = mei_txe_out_data_read(dev, i + 1);
+		memcpy(reg_buf, &reg, rem);
+	}
+
+	mei_txe_output_ready_set(hw);
+	return 0;
+}
+
+/**
+ * mei_txe_hw_reset - resets host and fw.
+ *
+ * @dev: the device structure
+ * @intr_enable: if interrupt should be enabled after reset.
+ *
+ * Return: 0 on success and < 0 in case of error
+ */
+static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	u32 aliveness_req;
+	/*
+	 * read input doorbell to ensure consistency between  Bridge and SeC
+	 * return value might be garbage return
+	 */
+	(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
+
+	aliveness_req = mei_txe_aliveness_req_get(dev);
+	hw->aliveness = mei_txe_aliveness_get(dev);
+
+	/* Disable interrupts in this stage we will poll */
+	mei_txe_intr_disable(dev);
+
+	/*
+	 * If Aliveness Request and Aliveness Response are not equal then
+	 * wait for them to be equal
+	 * Since we might have interrupts disabled - poll for it
+	 */
+	if (aliveness_req != hw->aliveness)
+		if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
+			dev_err(dev->dev, "wait for aliveness settle failed ... bailing out\n");
+			return -EIO;
+		}
+
+	/*
+	 * If Aliveness Request and Aliveness Response are set then clear them
+	 */
+	if (aliveness_req) {
+		mei_txe_aliveness_set(dev, 0);
+		if (mei_txe_aliveness_poll(dev, 0) < 0) {
+			dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
+			return -EIO;
+		}
+	}
+
+	/*
+	 * Set readiness RDY_CLR bit
+	 */
+	mei_txe_readiness_clear(dev);
+
+	return 0;
+}
+
+/**
+ * mei_txe_hw_start - start the hardware after reset
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success an error code otherwise
+ */
+static int mei_txe_hw_start(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	int ret;
+
+	u32 hisr;
+
+	/* bring back interrupts */
+	mei_txe_intr_enable(dev);
+
+	ret = mei_txe_readiness_wait(dev);
+	if (ret < 0) {
+		dev_err(dev->dev, "waiting for readiness failed\n");
+		return ret;
+	}
+
+	/*
+	 * If HISR.INT2_STS interrupt status bit is set then clear it.
+	 */
+	hisr = mei_txe_br_reg_read(hw, HISR_REG);
+	if (hisr & HISR_INT_2_STS)
+		mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_2_STS);
+
+	/* Clear the interrupt cause of OutputDoorbell */
+	clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause);
+
+	ret = mei_txe_aliveness_set_sync(dev, 1);
+	if (ret < 0) {
+		dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
+		return ret;
+	}
+
+	pm_runtime_set_active(dev->dev);
+
+	/* enable input ready interrupts:
+	 * SEC_IPC_HOST_INT_MASK.IPC_INPUT_READY_INT_MASK
+	 */
+	mei_txe_input_ready_interrupt_enable(dev);
+
+
+	/*  Set the SICR_SEC_IPC_OUTPUT_STATUS.IPC_OUTPUT_READY bit */
+	mei_txe_output_ready_set(hw);
+
+	/* Set bit SICR_HOST_IPC_READINESS.HOST_RDY
+	 */
+	mei_txe_readiness_set_host_rdy(dev);
+
+	return 0;
+}
+
+/**
+ * mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
+ *  single bit mask and acknowledge the interrupts
+ *
+ * @dev: the device structure
+ * @do_ack: acknowledge interrupts
+ *
+ * Return: true if found interrupts to process.
+ */
+static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	u32 hisr;
+	u32 hhisr;
+	u32 ipc_isr;
+	u32 aliveness;
+	bool generated;
+
+	/* read interrupt registers */
+	hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
+	generated = (hhisr & IPC_HHIER_MSK);
+	if (!generated)
+		goto out;
+
+	hisr = mei_txe_br_reg_read(hw, HISR_REG);
+
+	aliveness = mei_txe_aliveness_get(dev);
+	if (hhisr & IPC_HHIER_SEC && aliveness) {
+		ipc_isr = mei_txe_sec_reg_read_silent(hw,
+				SEC_IPC_HOST_INT_STATUS_REG);
+	} else {
+		ipc_isr = 0;
+		hhisr &= ~IPC_HHIER_SEC;
+	}
+
+	generated = generated ||
+		(hisr & HISR_INT_STS_MSK) ||
+		(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
+
+	if (generated && do_ack) {
+		/* Save the interrupt causes */
+		hw->intr_cause |= hisr & HISR_INT_STS_MSK;
+		if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
+			hw->intr_cause |= TXE_INTR_IN_READY;
+
+
+		mei_txe_intr_disable(dev);
+		/* Clear the interrupts in hierarchy:
+		 * IPC and Bridge, than the High Level */
+		mei_txe_sec_reg_write_silent(hw,
+			SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
+		mei_txe_br_reg_write(hw, HISR_REG, hisr);
+		mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
+	}
+
+out:
+	return generated;
+}
+
+/**
+ * mei_txe_irq_quick_handler - The ISR of the MEI device
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * Return: IRQ_WAKE_THREAD if interrupt is designed for the device
+ *         IRQ_NONE otherwise
+ */
+irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id)
+{
+	struct mei_device *dev = dev_id;
+
+	if (mei_txe_check_and_ack_intrs(dev, true))
+		return IRQ_WAKE_THREAD;
+	return IRQ_NONE;
+}
+
+
+/**
+ * mei_txe_irq_thread_handler - txe interrupt thread
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * Return: IRQ_HANDLED
+ */
+irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
+{
+	struct mei_device *dev = (struct mei_device *) dev_id;
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	struct list_head cmpl_list;
+	s32 slots;
+	int rets = 0;
+
+	dev_dbg(dev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
+		mei_txe_br_reg_read(hw, HHISR_REG),
+		mei_txe_br_reg_read(hw, HISR_REG),
+		mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
+
+
+	/* initialize our complete list */
+	mutex_lock(&dev->device_lock);
+	INIT_LIST_HEAD(&cmpl_list);
+
+	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
+		mei_txe_check_and_ack_intrs(dev, true);
+
+	/* show irq events */
+	mei_txe_pending_interrupts(dev);
+
+	hw->aliveness = mei_txe_aliveness_get(dev);
+	hw->readiness = mei_txe_readiness_get(dev);
+
+	/* Readiness:
+	 * Detection of TXE driver going through reset
+	 * or TXE driver resetting the HECI interface.
+	 */
+	if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
+		dev_dbg(dev->dev, "Readiness Interrupt was received...\n");
+
+		/* Check if SeC is going through reset */
+		if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
+			dev_dbg(dev->dev, "we need to start the dev.\n");
+			dev->recvd_hw_ready = true;
+		} else {
+			dev->recvd_hw_ready = false;
+			if (dev->dev_state != MEI_DEV_RESETTING) {
+
+				dev_warn(dev->dev, "FW not ready: resetting.\n");
+				schedule_work(&dev->reset_work);
+				goto end;
+
+			}
+		}
+		wake_up(&dev->wait_hw_ready);
+	}
+
+	/************************************************************/
+	/* Check interrupt cause:
+	 * Aliveness: Detection of SeC acknowledge of host request that
+	 * it remain alive or host cancellation of that request.
+	 */
+
+	if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
+		/* Clear the interrupt cause */
+		dev_dbg(dev->dev,
+			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		if (waitqueue_active(&hw->wait_aliveness_resp))
+			wake_up(&hw->wait_aliveness_resp);
+	}
+
+
+	/* Output Doorbell:
+	 * Detection of SeC having sent output to host
+	 */
+	slots = mei_count_full_read_slots(dev);
+	if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
+		/* Read from TXE */
+		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
+		if (rets &&
+		    (dev->dev_state != MEI_DEV_RESETTING &&
+		     dev->dev_state != MEI_DEV_POWER_DOWN)) {
+			dev_err(dev->dev,
+				"mei_irq_read_handler ret = %d.\n", rets);
+
+			schedule_work(&dev->reset_work);
+			goto end;
+		}
+	}
+	/* Input Ready: Detection if host can write to SeC */
+	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
+		dev->hbuf_is_ready = true;
+		hw->slots = TXE_HBUF_DEPTH;
+	}
+
+	if (hw->aliveness && dev->hbuf_is_ready) {
+		/* get the real register value */
+		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
+		rets = mei_irq_write_handler(dev, &cmpl_list);
+		if (rets && rets != -EMSGSIZE)
+			dev_err(dev->dev, "mei_irq_write_handler ret = %d.\n",
+				rets);
+		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
+	}
+
+	mei_irq_compl_handler(dev, &cmpl_list);
+
+end:
+	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
+
+	mutex_unlock(&dev->device_lock);
+
+	mei_enable_interrupts(dev);
+	return IRQ_HANDLED;
+}
+
+static const struct mei_hw_ops mei_txe_hw_ops = {
+
+	.host_is_ready = mei_txe_host_is_ready,
+
+	.fw_status = mei_txe_fw_status,
+	.pg_state = mei_txe_pg_state,
+
+	.hw_is_ready = mei_txe_hw_is_ready,
+	.hw_reset = mei_txe_hw_reset,
+	.hw_config = mei_txe_hw_config,
+	.hw_start = mei_txe_hw_start,
+
+	.pg_in_transition = mei_txe_pg_in_transition,
+	.pg_is_enabled = mei_txe_pg_is_enabled,
+
+	.intr_clear = mei_txe_intr_clear,
+	.intr_enable = mei_txe_intr_enable,
+	.intr_disable = mei_txe_intr_disable,
+	.synchronize_irq = mei_txe_synchronize_irq,
+
+	.hbuf_free_slots = mei_txe_hbuf_empty_slots,
+	.hbuf_is_ready = mei_txe_is_input_ready,
+	.hbuf_depth = mei_txe_hbuf_depth,
+
+	.write = mei_txe_write,
+
+	.rdbuf_full_slots = mei_txe_count_full_read_slots,
+	.read_hdr = mei_txe_read_hdr,
+
+	.read = mei_txe_read,
+
+};
+
+/**
+ * mei_txe_dev_init - allocates and initializes txe hardware specific structure
+ *
+ * @pdev: pci device
+ *
+ * Return: struct mei_device * on success or NULL
+ */
+struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+	struct mei_txe_hw *hw;
+
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	mei_device_init(dev, &pdev->dev, &mei_txe_hw_ops);
+
+	hw = to_txe_hw(dev);
+
+	init_waitqueue_head(&hw->wait_aliveness_resp);
+
+	return dev;
+}
+
+/**
+ * mei_txe_setup_satt2 - SATT2 configuration for DMA support.
+ *
+ * @dev:   the device structure
+ * @addr:  physical address start of the range
+ * @range: physical range size
+ *
+ * Return: 0 on success an error code otherwise
+ */
+int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+
+	u32 lo32 = lower_32_bits(addr);
+	u32 hi32 = upper_32_bits(addr);
+	u32 ctrl;
+
+	/* SATT is limited to 36 Bits */
+	if (hi32 & ~0xF)
+		return -EINVAL;
+
+	/* SATT has to be 16Byte aligned */
+	if (lo32 & 0xF)
+		return -EINVAL;
+
+	/* SATT range has to be 4Bytes aligned */
+	if (range & 0x4)
+		return -EINVAL;
+
+	/* SATT is limited to 32 MB range*/
+	if (range > SATT_RANGE_MAX)
+		return -EINVAL;
+
+	ctrl = SATT2_CTRL_VALID_MSK;
+	ctrl |= hi32  << SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT;
+
+	mei_txe_br_reg_write(hw, SATT2_SAP_SIZE_REG, range);
+	mei_txe_br_reg_write(hw, SATT2_BRG_BA_LSB_REG, lo32);
+	mei_txe_br_reg_write(hw, SATT2_CTRL_REG, ctrl);
+	dev_dbg(dev->dev, "SATT2: SAP_SIZE_OFFSET=0x%08X, BRG_BA_LSB_OFFSET=0x%08X, CTRL_OFFSET=0x%08X\n",
+		range, lo32, ctrl);
+
+	return 0;
+}
diff --git a/drivers/misc/mei/hw-txe.h b/drivers/misc/mei/hw-txe.h
new file mode 100644
index 000000000..96511b04b
--- /dev/null
+++ b/drivers/misc/mei/hw-txe.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2013-2016, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_HW_TXE_H_
+#define _MEI_HW_TXE_H_
+
+#include <linux/irqreturn.h>
+
+#include "hw.h"
+#include "hw-txe-regs.h"
+
+#define MEI_TXI_RPM_TIMEOUT    500 /* ms */
+
+/* Flatten Hierarchy interrupt cause */
+#define TXE_INTR_READINESS_BIT  0 /* HISR_INT_0_STS */
+#define TXE_INTR_READINESS      HISR_INT_0_STS
+#define TXE_INTR_ALIVENESS_BIT  1 /* HISR_INT_1_STS */
+#define TXE_INTR_ALIVENESS      HISR_INT_1_STS
+#define TXE_INTR_OUT_DB_BIT     2 /* HISR_INT_2_STS */
+#define TXE_INTR_OUT_DB         HISR_INT_2_STS
+#define TXE_INTR_IN_READY_BIT   8 /* beyond HISR */
+#define TXE_INTR_IN_READY       BIT(8)
+
+/**
+ * struct mei_txe_hw - txe hardware specifics
+ *
+ * @mem_addr:            SeC and BRIDGE bars
+ * @aliveness:           aliveness (power gating) state of the hardware
+ * @readiness:           readiness state of the hardware
+ * @slots:               number of empty slots
+ * @wait_aliveness_resp: aliveness wait queue
+ * @intr_cause:          translated interrupt cause
+ */
+struct mei_txe_hw {
+	void __iomem * const *mem_addr;
+	u32 aliveness;
+	u32 readiness;
+	u32 slots;
+
+	wait_queue_head_t wait_aliveness_resp;
+
+	unsigned long intr_cause;
+};
+
+#define to_txe_hw(dev) (struct mei_txe_hw *)((dev)->hw)
+
+static inline struct mei_device *hw_txe_to_mei(struct mei_txe_hw *hw)
+{
+	return container_of((void *)hw, struct mei_device, hw);
+}
+
+struct mei_device *mei_txe_dev_init(struct pci_dev *pdev);
+
+irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id);
+irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id);
+
+int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req);
+
+int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range);
+
+
+#endif /* _MEI_HW_TXE_H_ */
diff --git a/drivers/misc/mei/hw.h b/drivers/misc/mei/hw.h
new file mode 100644
index 000000000..df2fb9520
--- /dev/null
+++ b/drivers/misc/mei/hw.h
@@ -0,0 +1,674 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_HW_TYPES_H_
+#define _MEI_HW_TYPES_H_
+
+#include <linux/uuid.h>
+
+/*
+ * Timeouts in Seconds
+ */
+#define MEI_HW_READY_TIMEOUT        2  /* Timeout on ready message */
+#define MEI_CONNECT_TIMEOUT         3  /* HPS: at least 2 seconds */
+
+#define MEI_CL_CONNECT_TIMEOUT     15  /* HPS: Client Connect Timeout */
+#define MEI_CLIENTS_INIT_TIMEOUT   15  /* HPS: Clients Enumeration Timeout */
+
+#define MEI_PGI_TIMEOUT             1  /* PG Isolation time response 1 sec */
+#define MEI_D0I3_TIMEOUT            5  /* D0i3 set/unset max response time */
+#define MEI_HBM_TIMEOUT             1  /* 1 second */
+
+/*
+ * MEI Version
+ */
+#define HBM_MINOR_VERSION                   2
+#define HBM_MAJOR_VERSION                   2
+
+/*
+ * MEI version with PGI support
+ */
+#define HBM_MINOR_VERSION_PGI               1
+#define HBM_MAJOR_VERSION_PGI               1
+
+/*
+ * MEI version with Dynamic clients support
+ */
+#define HBM_MINOR_VERSION_DC               0
+#define HBM_MAJOR_VERSION_DC               2
+
+/*
+ * MEI version with immediate reply to enum request support
+ */
+#define HBM_MINOR_VERSION_IE               0
+#define HBM_MAJOR_VERSION_IE               2
+
+/*
+ * MEI version with disconnect on connection timeout support
+ */
+#define HBM_MINOR_VERSION_DOT              0
+#define HBM_MAJOR_VERSION_DOT              2
+
+/*
+ * MEI version with notification support
+ */
+#define HBM_MINOR_VERSION_EV               0
+#define HBM_MAJOR_VERSION_EV               2
+
+/*
+ * MEI version with fixed address client support
+ */
+#define HBM_MINOR_VERSION_FA               0
+#define HBM_MAJOR_VERSION_FA               2
+
+/*
+ * MEI version with OS ver message support
+ */
+#define HBM_MINOR_VERSION_OS               0
+#define HBM_MAJOR_VERSION_OS               2
+
+/*
+ * MEI version with dma ring support
+ */
+#define HBM_MINOR_VERSION_DR               1
+#define HBM_MAJOR_VERSION_DR               2
+
+/*
+ * MEI version with vm tag support
+ */
+#define HBM_MINOR_VERSION_VT               2
+#define HBM_MAJOR_VERSION_VT               2
+
+/*
+ * MEI version with capabilities message support
+ */
+#define HBM_MINOR_VERSION_CAP              2
+#define HBM_MAJOR_VERSION_CAP              2
+
+/* Host bus message command opcode */
+#define MEI_HBM_CMD_OP_MSK                  0x7f
+/* Host bus message command RESPONSE */
+#define MEI_HBM_CMD_RES_MSK                 0x80
+
+/*
+ * MEI Bus Message Command IDs
+ */
+#define HOST_START_REQ_CMD                  0x01
+#define HOST_START_RES_CMD                  0x81
+
+#define HOST_STOP_REQ_CMD                   0x02
+#define HOST_STOP_RES_CMD                   0x82
+
+#define ME_STOP_REQ_CMD                     0x03
+
+#define HOST_ENUM_REQ_CMD                   0x04
+#define HOST_ENUM_RES_CMD                   0x84
+
+#define HOST_CLIENT_PROPERTIES_REQ_CMD      0x05
+#define HOST_CLIENT_PROPERTIES_RES_CMD      0x85
+
+#define CLIENT_CONNECT_REQ_CMD              0x06
+#define CLIENT_CONNECT_RES_CMD              0x86
+
+#define CLIENT_DISCONNECT_REQ_CMD           0x07
+#define CLIENT_DISCONNECT_RES_CMD           0x87
+
+#define MEI_FLOW_CONTROL_CMD                0x08
+
+#define MEI_PG_ISOLATION_ENTRY_REQ_CMD      0x0a
+#define MEI_PG_ISOLATION_ENTRY_RES_CMD      0x8a
+#define MEI_PG_ISOLATION_EXIT_REQ_CMD       0x0b
+#define MEI_PG_ISOLATION_EXIT_RES_CMD       0x8b
+
+#define MEI_HBM_ADD_CLIENT_REQ_CMD          0x0f
+#define MEI_HBM_ADD_CLIENT_RES_CMD          0x8f
+
+#define MEI_HBM_NOTIFY_REQ_CMD              0x10
+#define MEI_HBM_NOTIFY_RES_CMD              0x90
+#define MEI_HBM_NOTIFICATION_CMD            0x11
+
+#define MEI_HBM_DMA_SETUP_REQ_CMD           0x12
+#define MEI_HBM_DMA_SETUP_RES_CMD           0x92
+
+#define MEI_HBM_CAPABILITIES_REQ_CMD        0x13
+#define MEI_HBM_CAPABILITIES_RES_CMD        0x93
+
+/*
+ * MEI Stop Reason
+ * used by hbm_host_stop_request.reason
+ */
+enum mei_stop_reason_types {
+	DRIVER_STOP_REQUEST = 0x00,
+	DEVICE_D1_ENTRY = 0x01,
+	DEVICE_D2_ENTRY = 0x02,
+	DEVICE_D3_ENTRY = 0x03,
+	SYSTEM_S1_ENTRY = 0x04,
+	SYSTEM_S2_ENTRY = 0x05,
+	SYSTEM_S3_ENTRY = 0x06,
+	SYSTEM_S4_ENTRY = 0x07,
+	SYSTEM_S5_ENTRY = 0x08
+};
+
+
+/**
+ * enum mei_hbm_status  - mei host bus messages return values
+ *
+ * @MEI_HBMS_SUCCESS           : status success
+ * @MEI_HBMS_CLIENT_NOT_FOUND  : client not found
+ * @MEI_HBMS_ALREADY_EXISTS    : connection already established
+ * @MEI_HBMS_REJECTED          : connection is rejected
+ * @MEI_HBMS_INVALID_PARAMETER : invalid parameter
+ * @MEI_HBMS_NOT_ALLOWED       : operation not allowed
+ * @MEI_HBMS_ALREADY_STARTED   : system is already started
+ * @MEI_HBMS_NOT_STARTED       : system not started
+ *
+ * @MEI_HBMS_MAX               : sentinel
+ */
+enum mei_hbm_status {
+	MEI_HBMS_SUCCESS           = 0,
+	MEI_HBMS_CLIENT_NOT_FOUND  = 1,
+	MEI_HBMS_ALREADY_EXISTS    = 2,
+	MEI_HBMS_REJECTED          = 3,
+	MEI_HBMS_INVALID_PARAMETER = 4,
+	MEI_HBMS_NOT_ALLOWED       = 5,
+	MEI_HBMS_ALREADY_STARTED   = 6,
+	MEI_HBMS_NOT_STARTED       = 7,
+
+	MEI_HBMS_MAX
+};
+
+
+/*
+ * Client Connect Status
+ * used by hbm_client_connect_response.status
+ */
+enum mei_cl_connect_status {
+	MEI_CL_CONN_SUCCESS          = MEI_HBMS_SUCCESS,
+	MEI_CL_CONN_NOT_FOUND        = MEI_HBMS_CLIENT_NOT_FOUND,
+	MEI_CL_CONN_ALREADY_STARTED  = MEI_HBMS_ALREADY_EXISTS,
+	MEI_CL_CONN_OUT_OF_RESOURCES = MEI_HBMS_REJECTED,
+	MEI_CL_CONN_MESSAGE_SMALL    = MEI_HBMS_INVALID_PARAMETER,
+	MEI_CL_CONN_NOT_ALLOWED      = MEI_HBMS_NOT_ALLOWED,
+};
+
+/*
+ * Client Disconnect Status
+ */
+enum mei_cl_disconnect_status {
+	MEI_CL_DISCONN_SUCCESS = MEI_HBMS_SUCCESS
+};
+
+/**
+ * enum mei_ext_hdr_type - extended header type used in
+ *    extended header TLV
+ *
+ * @MEI_EXT_HDR_NONE: sentinel
+ * @MEI_EXT_HDR_VTAG: vtag header
+ */
+enum mei_ext_hdr_type {
+	MEI_EXT_HDR_NONE = 0,
+	MEI_EXT_HDR_VTAG = 1,
+};
+
+/**
+ * struct mei_ext_hdr - extend header descriptor (TLV)
+ * @type: enum mei_ext_hdr_type
+ * @length: length excluding descriptor
+ * @ext_payload: payload of the specific extended header
+ * @hdr: place holder for actual header
+ */
+struct mei_ext_hdr {
+	u8 type;
+	u8 length;
+	u8 ext_payload[2];
+	u8 hdr[];
+};
+
+/**
+ * struct mei_ext_meta_hdr - extend header meta data
+ * @count: number of headers
+ * @size: total size of the extended header list excluding meta header
+ * @reserved: reserved
+ * @hdrs: extended headers TLV list
+ */
+struct mei_ext_meta_hdr {
+	u8 count;
+	u8 size;
+	u8 reserved[2];
+	struct mei_ext_hdr hdrs[];
+};
+
+/*
+ * Extended header iterator functions
+ */
+/**
+ * mei_ext_hdr - extended header iterator begin
+ *
+ * @meta: meta header of the extended header list
+ *
+ * Return:
+ *     The first extended header
+ */
+static inline struct mei_ext_hdr *mei_ext_begin(struct mei_ext_meta_hdr *meta)
+{
+	return meta->hdrs;
+}
+
+/**
+ * mei_ext_last - check if the ext is the last one in the TLV list
+ *
+ * @meta: meta header of the extended header list
+ * @ext: a meta header on the list
+ *
+ * Return: true if ext is the last header on the list
+ */
+static inline bool mei_ext_last(struct mei_ext_meta_hdr *meta,
+				struct mei_ext_hdr *ext)
+{
+	return (u8 *)ext >= (u8 *)meta + sizeof(*meta) + (meta->size * 4);
+}
+
+/**
+ *mei_ext_next - following extended header on the TLV list
+ *
+ * @ext: current extend header
+ *
+ * Context: The function does not check for the overflows,
+ *          one should call mei_ext_last before.
+ *
+ * Return: The following extend header after @ext
+ */
+static inline struct mei_ext_hdr *mei_ext_next(struct mei_ext_hdr *ext)
+{
+	return (struct mei_ext_hdr *)(ext->hdr + (ext->length * 4));
+}
+
+/**
+ * struct mei_msg_hdr - MEI BUS Interface Section
+ *
+ * @me_addr: device address
+ * @host_addr: host address
+ * @length: message length
+ * @reserved: reserved
+ * @extended: message has extended header
+ * @dma_ring: message is on dma ring
+ * @internal: message is internal
+ * @msg_complete: last packet of the message
+ * @extension: extension of the header
+ */
+struct mei_msg_hdr {
+	u32 me_addr:8;
+	u32 host_addr:8;
+	u32 length:9;
+	u32 reserved:3;
+	u32 extended:1;
+	u32 dma_ring:1;
+	u32 internal:1;
+	u32 msg_complete:1;
+	u32 extension[];
+} __packed;
+
+/* The length is up to 9 bits */
+#define MEI_MSG_MAX_LEN_MASK GENMASK(9, 0)
+
+struct mei_bus_message {
+	u8 hbm_cmd;
+	u8 data[];
+} __packed;
+
+/**
+ * struct hbm_cl_cmd - client specific host bus command
+ *	CONNECT, DISCONNECT, and FlOW CONTROL
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @host_addr: address of the client in the driver
+ * @data: generic data
+ */
+struct mei_hbm_cl_cmd {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 data;
+};
+
+struct hbm_version {
+	u8 minor_version;
+	u8 major_version;
+} __packed;
+
+struct hbm_host_version_request {
+	u8 hbm_cmd;
+	u8 reserved;
+	struct hbm_version host_version;
+} __packed;
+
+struct hbm_host_version_response {
+	u8 hbm_cmd;
+	u8 host_version_supported;
+	struct hbm_version me_max_version;
+} __packed;
+
+struct hbm_host_stop_request {
+	u8 hbm_cmd;
+	u8 reason;
+	u8 reserved[2];
+} __packed;
+
+struct hbm_host_stop_response {
+	u8 hbm_cmd;
+	u8 reserved[3];
+} __packed;
+
+struct hbm_me_stop_request {
+	u8 hbm_cmd;
+	u8 reason;
+	u8 reserved[2];
+} __packed;
+
+/**
+ * enum hbm_host_enum_flags - enumeration request flags (HBM version >= 2.0)
+ *
+ * @MEI_HBM_ENUM_F_ALLOW_ADD: allow dynamic clients add
+ * @MEI_HBM_ENUM_F_IMMEDIATE_ENUM: allow FW to send answer immediately
+ */
+enum hbm_host_enum_flags {
+	MEI_HBM_ENUM_F_ALLOW_ADD = BIT(0),
+	MEI_HBM_ENUM_F_IMMEDIATE_ENUM = BIT(1),
+};
+
+/**
+ * struct hbm_host_enum_request - enumeration request from host to fw
+ *
+ * @hbm_cmd : bus message command header
+ * @flags   : request flags
+ * @reserved: reserved
+ */
+struct hbm_host_enum_request {
+	u8 hbm_cmd;
+	u8 flags;
+	u8 reserved[2];
+} __packed;
+
+struct hbm_host_enum_response {
+	u8 hbm_cmd;
+	u8 reserved[3];
+	u8 valid_addresses[32];
+} __packed;
+
+/**
+ * struct mei_client_properties - mei client properties
+ *
+ * @protocol_name: guid of the client
+ * @protocol_version: client protocol version
+ * @max_number_of_connections: number of possible connections.
+ * @fixed_address: fixed me address (0 if the client is dynamic)
+ * @single_recv_buf: 1 if all connections share a single receive buffer.
+ * @vt_supported: the client support vtag
+ * @reserved: reserved
+ * @max_msg_length: MTU of the client
+ */
+struct mei_client_properties {
+	uuid_le protocol_name;
+	u8 protocol_version;
+	u8 max_number_of_connections;
+	u8 fixed_address;
+	u8 single_recv_buf:1;
+	u8 vt_supported:1;
+	u8 reserved:6;
+	u32 max_msg_length;
+} __packed;
+
+struct hbm_props_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 reserved[2];
+} __packed;
+
+struct hbm_props_response {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 status;
+	u8 reserved;
+	struct mei_client_properties client_properties;
+} __packed;
+
+/**
+ * struct hbm_add_client_request - request to add a client
+ *     might be sent by fw after enumeration has already completed
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @reserved: reserved
+ * @client_properties: client properties
+ */
+struct hbm_add_client_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 reserved[2];
+	struct mei_client_properties client_properties;
+} __packed;
+
+/**
+ * struct hbm_add_client_response - response to add a client
+ *     sent by the host to report client addition status to fw
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @status: if HBMS_SUCCESS then the client can now accept connections.
+ * @reserved: reserved
+ */
+struct hbm_add_client_response {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 status;
+	u8 reserved;
+} __packed;
+
+/**
+ * struct hbm_power_gate - power gate request/response
+ *
+ * @hbm_cmd: bus message command header
+ * @reserved: reserved
+ */
+struct hbm_power_gate {
+	u8 hbm_cmd;
+	u8 reserved[3];
+} __packed;
+
+/**
+ * struct hbm_client_connect_request - connect/disconnect request
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @host_addr: address of the client in the driver
+ * @reserved: reserved
+ */
+struct hbm_client_connect_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved;
+} __packed;
+
+/**
+ * struct hbm_client_connect_response - connect/disconnect response
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @host_addr: address of the client in the driver
+ * @status: status of the request
+ */
+struct hbm_client_connect_response {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 status;
+} __packed;
+
+
+#define MEI_FC_MESSAGE_RESERVED_LENGTH           5
+
+struct hbm_flow_control {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved[MEI_FC_MESSAGE_RESERVED_LENGTH];
+} __packed;
+
+#define MEI_HBM_NOTIFICATION_START 1
+#define MEI_HBM_NOTIFICATION_STOP  0
+/**
+ * struct hbm_notification_request - start/stop notification request
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @host_addr: address of the client in the driver
+ * @start:  start = 1 or stop = 0 asynchronous notifications
+ */
+struct hbm_notification_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 start;
+} __packed;
+
+/**
+ * struct hbm_notification_response - start/stop notification response
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr: address of the client in ME
+ * @host_addr: - address of the client in the driver
+ * @status: (mei_hbm_status) response status for the request
+ *  - MEI_HBMS_SUCCESS: successful stop/start
+ *  - MEI_HBMS_CLIENT_NOT_FOUND: if the connection could not be found.
+ *  - MEI_HBMS_ALREADY_STARTED: for start requests for a previously
+ *                         started notification.
+ *  - MEI_HBMS_NOT_STARTED: for stop request for a connected client for whom
+ *                         asynchronous notifications are currently disabled.
+ *
+ * @start:  start = 1 or stop = 0 asynchronous notifications
+ * @reserved: reserved
+ */
+struct hbm_notification_response {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 status;
+	u8 start;
+	u8 reserved[3];
+} __packed;
+
+/**
+ * struct hbm_notification - notification event
+ *
+ * @hbm_cmd: bus message command header
+ * @me_addr:  address of the client in ME
+ * @host_addr:  address of the client in the driver
+ * @reserved: reserved for alignment
+ */
+struct hbm_notification {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved;
+} __packed;
+
+/**
+ * struct hbm_dma_mem_dscr - dma ring
+ *
+ * @addr_hi: the high 32bits of 64 bit address
+ * @addr_lo: the low  32bits of 64 bit address
+ * @size   : size in bytes (must be power of 2)
+ */
+struct hbm_dma_mem_dscr {
+	u32 addr_hi;
+	u32 addr_lo;
+	u32 size;
+} __packed;
+
+enum {
+	DMA_DSCR_HOST = 0,
+	DMA_DSCR_DEVICE = 1,
+	DMA_DSCR_CTRL = 2,
+	DMA_DSCR_NUM,
+};
+
+/**
+ * struct hbm_dma_setup_request - dma setup request
+ *
+ * @hbm_cmd: bus message command header
+ * @reserved: reserved for alignment
+ * @dma_dscr: dma descriptor for HOST, DEVICE, and CTRL
+ */
+struct hbm_dma_setup_request {
+	u8 hbm_cmd;
+	u8 reserved[3];
+	struct hbm_dma_mem_dscr dma_dscr[DMA_DSCR_NUM];
+} __packed;
+
+/**
+ * struct hbm_dma_setup_response - dma setup response
+ *
+ * @hbm_cmd: bus message command header
+ * @status: 0 on success; otherwise DMA setup failed.
+ * @reserved: reserved for alignment
+ */
+struct hbm_dma_setup_response {
+	u8 hbm_cmd;
+	u8 status;
+	u8 reserved[2];
+} __packed;
+
+/**
+ * struct mei_dma_ring_ctrl - dma ring control block
+ *
+ * @hbuf_wr_idx: host circular buffer write index in slots
+ * @reserved1: reserved for alignment
+ * @hbuf_rd_idx: host circular buffer read index in slots
+ * @reserved2: reserved for alignment
+ * @dbuf_wr_idx: device circular buffer write index in slots
+ * @reserved3: reserved for alignment
+ * @dbuf_rd_idx: device circular buffer read index in slots
+ * @reserved4: reserved for alignment
+ */
+struct hbm_dma_ring_ctrl {
+	u32 hbuf_wr_idx;
+	u32 reserved1;
+	u32 hbuf_rd_idx;
+	u32 reserved2;
+	u32 dbuf_wr_idx;
+	u32 reserved3;
+	u32 dbuf_rd_idx;
+	u32 reserved4;
+} __packed;
+
+/* virtual tag supported */
+#define HBM_CAP_VT BIT(0)
+
+/**
+ * struct hbm_capability_request - capability request from host to fw
+ *
+ * @hbm_cmd : bus message command header
+ * @capability_requested: bitmask of capabilities requested by host
+ */
+struct hbm_capability_request {
+	u8 hbm_cmd;
+	u8 capability_requested[3];
+} __packed;
+
+/**
+ * struct hbm_capability_response - capability response from fw to host
+ *
+ * @hbm_cmd : bus message command header
+ * @capability_granted: bitmask of capabilities granted by FW
+ */
+struct hbm_capability_response {
+	u8 hbm_cmd;
+	u8 capability_granted[3];
+} __packed;
+
+#endif
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
new file mode 100644
index 000000000..bcee77768
--- /dev/null
+++ b/drivers/misc/mei/init.c
@@ -0,0 +1,398 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2019, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+const char *mei_dev_state_str(int state)
+{
+#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
+	switch (state) {
+	MEI_DEV_STATE(INITIALIZING);
+	MEI_DEV_STATE(INIT_CLIENTS);
+	MEI_DEV_STATE(ENABLED);
+	MEI_DEV_STATE(RESETTING);
+	MEI_DEV_STATE(DISABLED);
+	MEI_DEV_STATE(POWER_DOWN);
+	MEI_DEV_STATE(POWER_UP);
+	default:
+		return "unknown";
+	}
+#undef MEI_DEV_STATE
+}
+
+const char *mei_pg_state_str(enum mei_pg_state state)
+{
+#define MEI_PG_STATE(state) case MEI_PG_##state: return #state
+	switch (state) {
+	MEI_PG_STATE(OFF);
+	MEI_PG_STATE(ON);
+	default:
+		return "unknown";
+	}
+#undef MEI_PG_STATE
+}
+
+/**
+ * mei_fw_status2str - convert fw status registers to printable string
+ *
+ * @fw_status:  firmware status
+ * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
+ * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
+ *
+ * Return: number of bytes written or -EINVAL if buffer is to small
+ */
+ssize_t mei_fw_status2str(struct mei_fw_status *fw_status,
+			  char *buf, size_t len)
+{
+	ssize_t cnt = 0;
+	int i;
+
+	buf[0] = '\0';
+
+	if (len < MEI_FW_STATUS_STR_SZ)
+		return -EINVAL;
+
+	for (i = 0; i < fw_status->count; i++)
+		cnt += scnprintf(buf + cnt, len - cnt, "%08X ",
+				fw_status->status[i]);
+
+	/* drop last space */
+	buf[cnt] = '\0';
+	return cnt;
+}
+EXPORT_SYMBOL_GPL(mei_fw_status2str);
+
+/**
+ * mei_cancel_work - Cancel mei background jobs
+ *
+ * @dev: the device structure
+ */
+void mei_cancel_work(struct mei_device *dev)
+{
+	cancel_work_sync(&dev->reset_work);
+	cancel_work_sync(&dev->bus_rescan_work);
+
+	cancel_delayed_work_sync(&dev->timer_work);
+}
+EXPORT_SYMBOL_GPL(mei_cancel_work);
+
+/**
+ * mei_reset - resets host and fw.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success or < 0 if the reset hasn't succeeded
+ */
+int mei_reset(struct mei_device *dev)
+{
+	enum mei_dev_state state = dev->dev_state;
+	bool interrupts_enabled;
+	int ret;
+
+	if (state != MEI_DEV_INITIALIZING &&
+	    state != MEI_DEV_DISABLED &&
+	    state != MEI_DEV_POWER_DOWN &&
+	    state != MEI_DEV_POWER_UP) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		dev_warn(dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
+			 mei_dev_state_str(state), fw_sts_str);
+	}
+
+	mei_clear_interrupts(dev);
+
+	/* we're already in reset, cancel the init timer
+	 * if the reset was called due the hbm protocol error
+	 * we need to call it before hw start
+	 * so the hbm watchdog won't kick in
+	 */
+	mei_hbm_idle(dev);
+
+	/* enter reset flow */
+	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
+	mei_set_devstate(dev, MEI_DEV_RESETTING);
+
+	dev->reset_count++;
+	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
+		dev_err(dev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return -ENODEV;
+	}
+
+	ret = mei_hw_reset(dev, interrupts_enabled);
+	/* fall through and remove the sw state even if hw reset has failed */
+
+	/* no need to clean up software state in case of power up */
+	if (state != MEI_DEV_INITIALIZING && state != MEI_DEV_POWER_UP)
+		mei_cl_all_disconnect(dev);
+
+	mei_hbm_reset(dev);
+
+	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+
+	if (ret) {
+		dev_err(dev->dev, "hw_reset failed ret = %d\n", ret);
+		return ret;
+	}
+
+	if (state == MEI_DEV_POWER_DOWN) {
+		dev_dbg(dev->dev, "powering down: end of reset\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return 0;
+	}
+
+	ret = mei_hw_start(dev);
+	if (ret) {
+		dev_err(dev->dev, "hw_start failed ret = %d\n", ret);
+		return ret;
+	}
+
+	dev_dbg(dev->dev, "link is established start sending messages.\n");
+
+	mei_set_devstate(dev, MEI_DEV_INIT_CLIENTS);
+	ret = mei_hbm_start_req(dev);
+	if (ret) {
+		dev_err(dev->dev, "hbm_start failed ret = %d\n", ret);
+		mei_set_devstate(dev, MEI_DEV_RESETTING);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_reset);
+
+/**
+ * mei_start - initializes host and fw to start work.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_start(struct mei_device *dev)
+{
+	int ret;
+
+	mutex_lock(&dev->device_lock);
+
+	/* acknowledge interrupt and stop interrupts */
+	mei_clear_interrupts(dev);
+
+	ret = mei_hw_config(dev);
+	if (ret)
+		goto err;
+
+	dev_dbg(dev->dev, "reset in start the mei device.\n");
+
+	dev->reset_count = 0;
+	do {
+		mei_set_devstate(dev, MEI_DEV_INITIALIZING);
+		ret = mei_reset(dev);
+
+		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+			dev_err(dev->dev, "reset failed ret = %d", ret);
+			goto err;
+		}
+	} while (ret);
+
+	if (mei_hbm_start_wait(dev)) {
+		dev_err(dev->dev, "HBM haven't started");
+		goto err;
+	}
+
+	if (!mei_host_is_ready(dev)) {
+		dev_err(dev->dev, "host is not ready.\n");
+		goto err;
+	}
+
+	if (!mei_hw_is_ready(dev)) {
+		dev_err(dev->dev, "ME is not ready.\n");
+		goto err;
+	}
+
+	if (!mei_hbm_version_is_supported(dev)) {
+		dev_dbg(dev->dev, "MEI start failed.\n");
+		goto err;
+	}
+
+	dev_dbg(dev->dev, "link layer has been established.\n");
+
+	mutex_unlock(&dev->device_lock);
+	return 0;
+err:
+	dev_err(dev->dev, "link layer initialization failed.\n");
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
+	mutex_unlock(&dev->device_lock);
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(mei_start);
+
+/**
+ * mei_restart - restart device after suspend
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success or -ENODEV if the restart hasn't succeeded
+ */
+int mei_restart(struct mei_device *dev)
+{
+	int err;
+
+	mutex_lock(&dev->device_lock);
+
+	mei_set_devstate(dev, MEI_DEV_POWER_UP);
+	dev->reset_count = 0;
+
+	err = mei_reset(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(dev->dev, "device disabled = %d\n", err);
+		return -ENODEV;
+	}
+
+	/* try to start again */
+	if (err)
+		schedule_work(&dev->reset_work);
+
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_restart);
+
+static void mei_reset_work(struct work_struct *work)
+{
+	struct mei_device *dev =
+		container_of(work, struct mei_device,  reset_work);
+	int ret;
+
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
+
+	mutex_lock(&dev->device_lock);
+
+	ret = mei_reset(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(dev->dev, "device disabled = %d\n", ret);
+		return;
+	}
+
+	/* retry reset in case of failure */
+	if (ret)
+		schedule_work(&dev->reset_work);
+}
+
+void mei_stop(struct mei_device *dev)
+{
+	dev_dbg(dev->dev, "stopping the device.\n");
+
+	mutex_lock(&dev->device_lock);
+	mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
+	mutex_unlock(&dev->device_lock);
+	mei_cl_bus_remove_devices(dev);
+
+	mei_cancel_work(dev);
+
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
+
+	mutex_lock(&dev->device_lock);
+
+	mei_reset(dev);
+	/* move device to disabled state unconditionally */
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
+
+	mutex_unlock(&dev->device_lock);
+}
+EXPORT_SYMBOL_GPL(mei_stop);
+
+/**
+ * mei_write_is_idle - check if the write queues are idle
+ *
+ * @dev: the device structure
+ *
+ * Return: true of there is no pending write
+ */
+bool mei_write_is_idle(struct mei_device *dev)
+{
+	bool idle = (dev->dev_state == MEI_DEV_ENABLED &&
+		list_empty(&dev->ctrl_wr_list) &&
+		list_empty(&dev->write_list)   &&
+		list_empty(&dev->write_waiting_list));
+
+	dev_dbg(dev->dev, "write pg: is idle[%d] state=%s ctrl=%01d write=%01d wwait=%01d\n",
+		idle,
+		mei_dev_state_str(dev->dev_state),
+		list_empty(&dev->ctrl_wr_list),
+		list_empty(&dev->write_list),
+		list_empty(&dev->write_waiting_list));
+
+	return idle;
+}
+EXPORT_SYMBOL_GPL(mei_write_is_idle);
+
+/**
+ * mei_device_init  -- initialize mei_device structure
+ *
+ * @dev: the mei device
+ * @device: the device structure
+ * @hw_ops: hw operations
+ */
+void mei_device_init(struct mei_device *dev,
+		     struct device *device,
+		     const struct mei_hw_ops *hw_ops)
+{
+	/* setup our list array */
+	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->device_list);
+	INIT_LIST_HEAD(&dev->me_clients);
+	mutex_init(&dev->device_lock);
+	init_rwsem(&dev->me_clients_rwsem);
+	mutex_init(&dev->cl_bus_lock);
+	init_waitqueue_head(&dev->wait_hw_ready);
+	init_waitqueue_head(&dev->wait_pg);
+	init_waitqueue_head(&dev->wait_hbm_start);
+	dev->dev_state = MEI_DEV_INITIALIZING;
+	dev->reset_count = 0;
+
+	INIT_LIST_HEAD(&dev->write_list);
+	INIT_LIST_HEAD(&dev->write_waiting_list);
+	INIT_LIST_HEAD(&dev->ctrl_wr_list);
+	INIT_LIST_HEAD(&dev->ctrl_rd_list);
+	dev->tx_queue_limit = MEI_TX_QUEUE_LIMIT_DEFAULT;
+
+	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
+	INIT_WORK(&dev->reset_work, mei_reset_work);
+	INIT_WORK(&dev->bus_rescan_work, mei_cl_bus_rescan_work);
+
+	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
+	dev->open_handle_count = 0;
+
+	/*
+	 * Reserving the first client ID
+	 * 0: Reserved for MEI Bus Message communications
+	 */
+	bitmap_set(dev->host_clients_map, 0, 1);
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev->ops      = hw_ops;
+	dev->dev      = device;
+}
+EXPORT_SYMBOL_GPL(mei_device_init);
+
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
new file mode 100644
index 000000000..ca3067fa6
--- /dev/null
+++ b/drivers/misc/mei/interrupt.c
@@ -0,0 +1,648 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/export.h>
+#include <linux/kthread.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+
+/**
+ * mei_irq_compl_handler - dispatch complete handlers
+ *	for the completed callbacks
+ *
+ * @dev: mei device
+ * @cmpl_list: list of completed cbs
+ */
+void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list)
+{
+	struct mei_cl_cb *cb, *next;
+	struct mei_cl *cl;
+
+	list_for_each_entry_safe(cb, next, cmpl_list, list) {
+		cl = cb->cl;
+		list_del_init(&cb->list);
+
+		dev_dbg(dev->dev, "completing call back.\n");
+		mei_cl_complete(cl, cb);
+	}
+}
+EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
+
+/**
+ * mei_cl_hbm_equal - check if hbm is addressed to the client
+ *
+ * @cl: host client
+ * @mei_hdr: header of mei client message
+ *
+ * Return: true if matches, false otherwise
+ */
+static inline int mei_cl_hbm_equal(struct mei_cl *cl,
+			struct mei_msg_hdr *mei_hdr)
+{
+	return  mei_cl_host_addr(cl) == mei_hdr->host_addr &&
+		mei_cl_me_id(cl) == mei_hdr->me_addr;
+}
+
+/**
+ * mei_irq_discard_msg  - discard received message
+ *
+ * @dev: mei device
+ * @hdr: message header
+ * @discard_len: the length of the message to discard (excluding header)
+ */
+static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr,
+				size_t discard_len)
+{
+	if (hdr->dma_ring) {
+		mei_dma_ring_read(dev, NULL,
+				  hdr->extension[dev->rd_msg_hdr_count - 2]);
+		discard_len = 0;
+	}
+	/*
+	 * no need to check for size as it is guarantied
+	 * that length fits into rd_msg_buf
+	 */
+	mei_read_slots(dev, dev->rd_msg_buf, discard_len);
+	dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
+		MEI_HDR_PRM(hdr));
+}
+
+/**
+ * mei_cl_irq_read_msg - process client message
+ *
+ * @cl: reading client
+ * @mei_hdr: header of mei client message
+ * @meta: extend meta header
+ * @cmpl_list: completion list
+ *
+ * Return: always 0
+ */
+static int mei_cl_irq_read_msg(struct mei_cl *cl,
+			       struct mei_msg_hdr *mei_hdr,
+			       struct mei_ext_meta_hdr *meta,
+			       struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	struct mei_cl_cb *cb;
+
+	size_t buf_sz;
+	u32 length;
+	int ext_len;
+
+	length = mei_hdr->length;
+	ext_len = 0;
+	if (mei_hdr->extended) {
+		ext_len = sizeof(*meta) + mei_slots2data(meta->size);
+		length -= ext_len;
+	}
+
+	cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
+	if (!cb) {
+		if (!mei_cl_is_fixed_address(cl)) {
+			cl_err(dev, cl, "pending read cb not found\n");
+			goto discard;
+		}
+		cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp);
+		if (!cb)
+			goto discard;
+		list_add_tail(&cb->list, &cl->rd_pending);
+	}
+
+	if (mei_hdr->extended) {
+		struct mei_ext_hdr *ext;
+		struct mei_ext_hdr *vtag = NULL;
+
+		ext = mei_ext_begin(meta);
+		do {
+			switch (ext->type) {
+			case MEI_EXT_HDR_VTAG:
+				vtag = ext;
+				break;
+			case MEI_EXT_HDR_NONE:
+				fallthrough;
+			default:
+				cb->status = -EPROTO;
+				break;
+			}
+
+			ext = mei_ext_next(ext);
+		} while (!mei_ext_last(meta, ext));
+
+		if (!vtag) {
+			cl_dbg(dev, cl, "vtag not found in extended header.\n");
+			cb->status = -EPROTO;
+			goto discard;
+		}
+
+		cl_dbg(dev, cl, "vtag: %d\n", vtag->ext_payload[0]);
+		if (cb->vtag && cb->vtag != vtag->ext_payload[0]) {
+			cl_err(dev, cl, "mismatched tag: %d != %d\n",
+			       cb->vtag, vtag->ext_payload[0]);
+			cb->status = -EPROTO;
+			goto discard;
+		}
+		cb->vtag = vtag->ext_payload[0];
+	}
+
+	if (!mei_cl_is_connected(cl)) {
+		cl_dbg(dev, cl, "not connected\n");
+		cb->status = -ENODEV;
+		goto discard;
+	}
+
+	if (mei_hdr->dma_ring)
+		length = mei_hdr->extension[mei_data2slots(ext_len)];
+
+	buf_sz = length + cb->buf_idx;
+	/* catch for integer overflow */
+	if (buf_sz < cb->buf_idx) {
+		cl_err(dev, cl, "message is too big len %d idx %zu\n",
+		       length, cb->buf_idx);
+		cb->status = -EMSGSIZE;
+		goto discard;
+	}
+
+	if (cb->buf.size < buf_sz) {
+		cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
+			cb->buf.size, length, cb->buf_idx);
+		cb->status = -EMSGSIZE;
+		goto discard;
+	}
+
+	if (mei_hdr->dma_ring) {
+		mei_dma_ring_read(dev, cb->buf.data + cb->buf_idx, length);
+		/*  for DMA read 0 length to generate interrupt to the device */
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, 0);
+	} else {
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, length);
+	}
+
+	cb->buf_idx += length;
+
+	if (mei_hdr->msg_complete) {
+		cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
+		list_move_tail(&cb->list, cmpl_list);
+	} else {
+		pm_runtime_mark_last_busy(dev->dev);
+		pm_request_autosuspend(dev->dev);
+	}
+
+	return 0;
+
+discard:
+	if (cb)
+		list_move_tail(&cb->list, cmpl_list);
+	mei_irq_discard_msg(dev, mei_hdr, length);
+	return 0;
+}
+
+/**
+ * mei_cl_irq_disconnect_rsp - send disconnection response message
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
+				     struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_response));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	ret = mei_hbm_cl_disconnect_rsp(dev, cl);
+	list_move_tail(&cb->list, cmpl_list);
+
+	return ret;
+}
+
+/**
+ * mei_cl_irq_read - processes client read related operation from the
+ *	interrupt thread context - request for flow control credits
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
+			   struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+
+	if (!list_empty(&cl->rd_pending))
+		return 0;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_flow_control));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	ret = mei_hbm_cl_flow_control_req(dev, cl);
+	if (ret) {
+		cl->status = ret;
+		cb->buf_idx = 0;
+		list_move_tail(&cb->list, cmpl_list);
+		return ret;
+	}
+
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_request_autosuspend(dev->dev);
+
+	list_move_tail(&cb->list, &cl->rd_pending);
+
+	return 0;
+}
+
+static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
+{
+	return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
+}
+
+static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
+{
+	return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
+}
+
+static inline int hdr_is_valid(u32 msg_hdr)
+{
+	struct mei_msg_hdr *mei_hdr;
+	u32 expected_len = 0;
+
+	mei_hdr = (struct mei_msg_hdr *)&msg_hdr;
+	if (!msg_hdr || mei_hdr->reserved)
+		return -EBADMSG;
+
+	if (mei_hdr->dma_ring)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->extended)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->length < expected_len)
+		return -EBADMSG;
+
+	return 0;
+}
+
+/**
+ * mei_irq_read_handler - bottom half read routine after ISR to
+ * handle the read processing.
+ *
+ * @dev: the device structure
+ * @cmpl_list: An instance of our list structure
+ * @slots: slots to read.
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_irq_read_handler(struct mei_device *dev,
+			 struct list_head *cmpl_list, s32 *slots)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct mei_ext_meta_hdr *meta_hdr = NULL;
+	struct mei_cl *cl;
+	int ret;
+	u32 ext_meta_hdr_u32;
+	u32 hdr_size_left;
+	u32 hdr_size_ext;
+	int i;
+	int ext_hdr_end;
+
+	if (!dev->rd_msg_hdr[0]) {
+		dev->rd_msg_hdr[0] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count = 1;
+		(*slots)--;
+		dev_dbg(dev->dev, "slots =%08x.\n", *slots);
+
+		ret = hdr_is_valid(dev->rd_msg_hdr[0]);
+		if (ret) {
+			dev_err(dev->dev, "corrupted message header 0x%08X\n",
+				dev->rd_msg_hdr[0]);
+			goto end;
+		}
+	}
+
+	mei_hdr = (struct mei_msg_hdr *)dev->rd_msg_hdr;
+	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
+
+	if (mei_slots2data(*slots) < mei_hdr->length) {
+		dev_err(dev->dev, "less data available than length=%08x.\n",
+				*slots);
+		/* we can't read the message */
+		ret = -ENODATA;
+		goto end;
+	}
+
+	ext_hdr_end = 1;
+	hdr_size_left = mei_hdr->length;
+
+	if (mei_hdr->extended) {
+		if (!dev->rd_msg_hdr[1]) {
+			ext_meta_hdr_u32 = mei_read_hdr(dev);
+			dev->rd_msg_hdr[1] = ext_meta_hdr_u32;
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+			dev_dbg(dev->dev, "extended header is %08x\n",
+				ext_meta_hdr_u32);
+		}
+		meta_hdr = ((struct mei_ext_meta_hdr *)dev->rd_msg_hdr + 1);
+		if (check_add_overflow((u32)sizeof(*meta_hdr),
+				       mei_slots2data(meta_hdr->size),
+				       &hdr_size_ext)) {
+			dev_err(dev->dev, "extended message size too big %d\n",
+				meta_hdr->size);
+			return -EBADMSG;
+		}
+		if (hdr_size_left < hdr_size_ext) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+		hdr_size_left -= hdr_size_ext;
+
+		ext_hdr_end = meta_hdr->size + 2;
+		for (i = dev->rd_msg_hdr_count; i < ext_hdr_end; i++) {
+			dev->rd_msg_hdr[i] = mei_read_hdr(dev);
+			dev_dbg(dev->dev, "extended header %d is %08x\n", i,
+				dev->rd_msg_hdr[i]);
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+		}
+	}
+
+	if (mei_hdr->dma_ring) {
+		if (hdr_size_left != sizeof(dev->rd_msg_hdr[ext_hdr_end])) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+
+		dev->rd_msg_hdr[ext_hdr_end] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count++;
+		(*slots)--;
+		mei_hdr->length -= sizeof(dev->rd_msg_hdr[ext_hdr_end]);
+	}
+
+	/*  HBM message */
+	if (hdr_is_hbm(mei_hdr)) {
+		ret = mei_hbm_dispatch(dev, mei_hdr);
+		if (ret) {
+			dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
+					ret);
+			goto end;
+		}
+		goto reset_slots;
+	}
+
+	/* find recipient cl */
+	list_for_each_entry(cl, &dev->file_list, link) {
+		if (mei_cl_hbm_equal(cl, mei_hdr)) {
+			cl_dbg(dev, cl, "got a message\n");
+			ret = mei_cl_irq_read_msg(cl, mei_hdr, meta_hdr, cmpl_list);
+			goto reset_slots;
+		}
+	}
+
+	/* if no recipient cl was found we assume corrupted header */
+	/* A message for not connected fixed address clients
+	 * should be silently discarded
+	 * On power down client may be force cleaned,
+	 * silently discard such messages
+	 */
+	if (hdr_is_fixed(mei_hdr) ||
+	    dev->dev_state == MEI_DEV_POWER_DOWN) {
+		mei_irq_discard_msg(dev, mei_hdr, mei_hdr->length);
+		ret = 0;
+		goto reset_slots;
+	}
+	dev_err(dev->dev, "no destination client found 0x%08X\n", dev->rd_msg_hdr[0]);
+	ret = -EBADMSG;
+	goto end;
+
+reset_slots:
+	/* reset the number of slots and header */
+	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+	dev->rd_msg_hdr_count = 0;
+	*slots = mei_count_full_read_slots(dev);
+	if (*slots == -EOVERFLOW) {
+		/* overflow - reset */
+		dev_err(dev->dev, "resetting due to slots overflow.\n");
+		/* set the event since message has been read */
+		ret = -ERANGE;
+		goto end;
+	}
+end:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_irq_read_handler);
+
+
+/**
+ * mei_irq_write_handler -  dispatch write requests
+ *  after irq received
+ *
+ * @dev: the device structure
+ * @cmpl_list: An instance of our list structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list)
+{
+
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+	s32 slots;
+	int ret;
+
+
+	if (!mei_hbuf_acquire(dev))
+		return 0;
+
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if (slots == 0)
+		return -EMSGSIZE;
+
+	/* complete all waiting for write CB */
+	dev_dbg(dev->dev, "complete all waiting for write cb.\n");
+
+	list_for_each_entry_safe(cb, next, &dev->write_waiting_list, list) {
+		cl = cb->cl;
+
+		cl->status = 0;
+		cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
+		cl->writing_state = MEI_WRITE_COMPLETE;
+		list_move_tail(&cb->list, cmpl_list);
+	}
+
+	/* complete control write list CB */
+	dev_dbg(dev->dev, "complete control write list cb.\n");
+	list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list, list) {
+		cl = cb->cl;
+		switch (cb->fop_type) {
+		case MEI_FOP_DISCONNECT:
+			/* send disconnect message */
+			ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_READ:
+			/* send flow control message */
+			ret = mei_cl_irq_read(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_CONNECT:
+			/* connect message */
+			ret = mei_cl_irq_connect(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_DISCONNECT_RSP:
+			/* send disconnect resp */
+			ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+
+		case MEI_FOP_NOTIFY_START:
+		case MEI_FOP_NOTIFY_STOP:
+			ret = mei_cl_irq_notify(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+		default:
+			BUG();
+		}
+
+	}
+	/* complete  write list CB */
+	dev_dbg(dev->dev, "complete write list cb.\n");
+	list_for_each_entry_safe(cb, next, &dev->write_list, list) {
+		cl = cb->cl;
+		ret = mei_cl_irq_write(cl, cb, cmpl_list);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_irq_write_handler);
+
+
+/**
+ * mei_connect_timeout  - connect/disconnect timeouts
+ *
+ * @cl: host client
+ */
+static void mei_connect_timeout(struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+
+	if (cl->state == MEI_FILE_CONNECTING) {
+		if (dev->hbm_f_dot_supported) {
+			cl->state = MEI_FILE_DISCONNECT_REQUIRED;
+			wake_up(&cl->wait);
+			return;
+		}
+	}
+	mei_reset(dev);
+}
+
+#define MEI_STALL_TIMER_FREQ (2 * HZ)
+/**
+ * mei_schedule_stall_timer - re-arm stall_timer work
+ *
+ * Schedule stall timer
+ *
+ * @dev: the device structure
+ */
+void mei_schedule_stall_timer(struct mei_device *dev)
+{
+	schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ);
+}
+
+/**
+ * mei_timer - timer function.
+ *
+ * @work: pointer to the work_struct structure
+ *
+ */
+void mei_timer(struct work_struct *work)
+{
+	struct mei_cl *cl;
+	struct mei_device *dev = container_of(work,
+					struct mei_device, timer_work.work);
+	bool reschedule_timer = false;
+
+	mutex_lock(&dev->device_lock);
+
+	/* Catch interrupt stalls during HBM init handshake */
+	if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
+	    dev->hbm_state != MEI_HBM_IDLE) {
+
+		if (dev->init_clients_timer) {
+			if (--dev->init_clients_timer == 0) {
+				dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
+					dev->hbm_state);
+				mei_reset(dev);
+				goto out;
+			}
+			reschedule_timer = true;
+		}
+	}
+
+	if (dev->dev_state != MEI_DEV_ENABLED)
+		goto out;
+
+	/*** connect/disconnect timeouts ***/
+	list_for_each_entry(cl, &dev->file_list, link) {
+		if (cl->timer_count) {
+			if (--cl->timer_count == 0) {
+				dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
+				mei_connect_timeout(cl);
+				goto out;
+			}
+			reschedule_timer = true;
+		}
+	}
+
+out:
+	if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer)
+		mei_schedule_stall_timer(dev);
+
+	mutex_unlock(&dev->device_lock);
+}
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
new file mode 100644
index 000000000..9f6682033
--- /dev/null
+++ b/drivers/misc/mei/main.c
@@ -0,0 +1,1322 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/sched/signal.h>
+#include <linux/uuid.h>
+#include <linux/compat.h>
+#include <linux/jiffies.h>
+#include <linux/interrupt.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "client.h"
+
+static struct class *mei_class;
+static dev_t mei_devt;
+#define MEI_MAX_DEVS  MINORMASK
+static DEFINE_MUTEX(mei_minor_lock);
+static DEFINE_IDR(mei_idr);
+
+/**
+ * mei_open - the open function
+ *
+ * @inode: pointer to inode structure
+ * @file: pointer to file structure
+ *
+ * Return: 0 on success, <0 on error
+ */
+static int mei_open(struct inode *inode, struct file *file)
+{
+	struct mei_device *dev;
+	struct mei_cl *cl;
+
+	int err;
+
+	dev = container_of(inode->i_cdev, struct mei_device, cdev);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (dev->dev_state != MEI_DEV_ENABLED) {
+		dev_dbg(dev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
+		    mei_dev_state_str(dev->dev_state));
+		err = -ENODEV;
+		goto err_unlock;
+	}
+
+	cl = mei_cl_alloc_linked(dev);
+	if (IS_ERR(cl)) {
+		err = PTR_ERR(cl);
+		goto err_unlock;
+	}
+
+	cl->fp = file;
+	file->private_data = cl;
+
+	mutex_unlock(&dev->device_lock);
+
+	return nonseekable_open(inode, file);
+
+err_unlock:
+	mutex_unlock(&dev->device_lock);
+	return err;
+}
+
+/**
+ * mei_cl_vtag_remove_by_fp - remove vtag that corresponds to fp from list
+ *
+ * @cl: host client
+ * @fp: pointer to file structure
+ *
+ */
+static void mei_cl_vtag_remove_by_fp(const struct mei_cl *cl,
+				     const struct file *fp)
+{
+	struct mei_cl_vtag *vtag_l, *next;
+
+	list_for_each_entry_safe(vtag_l, next, &cl->vtag_map, list) {
+		if (vtag_l->fp == fp) {
+			list_del(&vtag_l->list);
+			kfree(vtag_l);
+			return;
+		}
+	}
+}
+
+/**
+ * mei_release - the release function
+ *
+ * @inode: pointer to inode structure
+ * @file: pointer to file structure
+ *
+ * Return: 0 on success, <0 on error
+ */
+static int mei_release(struct inode *inode, struct file *file)
+{
+	struct mei_cl *cl = file->private_data;
+	struct mei_device *dev;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->device_lock);
+
+	mei_cl_vtag_remove_by_fp(cl, file);
+
+	if (!list_empty(&cl->vtag_map)) {
+		cl_dbg(dev, cl, "not the last vtag\n");
+		mei_cl_flush_queues(cl, file);
+		rets = 0;
+		goto out;
+	}
+
+	rets = mei_cl_disconnect(cl);
+	/*
+	 * Check again: This is necessary since disconnect releases the lock
+	 * and another client can connect in the meantime.
+	 */
+	if (!list_empty(&cl->vtag_map)) {
+		cl_dbg(dev, cl, "not the last vtag after disconnect\n");
+		mei_cl_flush_queues(cl, file);
+		goto out;
+	}
+
+	mei_cl_flush_queues(cl, NULL);
+	cl_dbg(dev, cl, "removing\n");
+
+	mei_cl_unlink(cl);
+	kfree(cl);
+
+out:
+	file->private_data = NULL;
+
+	mutex_unlock(&dev->device_lock);
+	return rets;
+}
+
+
+/**
+ * mei_read - the read function.
+ *
+ * @file: pointer to file structure
+ * @ubuf: pointer to user buffer
+ * @length: buffer length
+ * @offset: data offset in buffer
+ *
+ * Return: >=0 data length on success , <0 on error
+ */
+static ssize_t mei_read(struct file *file, char __user *ubuf,
+			size_t length, loff_t *offset)
+{
+	struct mei_cl *cl = file->private_data;
+	struct mei_device *dev;
+	struct mei_cl_cb *cb = NULL;
+	bool nonblock = !!(file->f_flags & O_NONBLOCK);
+	ssize_t rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+
+	mutex_lock(&dev->device_lock);
+	if (dev->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	if (length == 0) {
+		rets = 0;
+		goto out;
+	}
+
+	if (ubuf == NULL) {
+		rets = -EMSGSIZE;
+		goto out;
+	}
+
+	cb = mei_cl_read_cb(cl, file);
+	if (cb)
+		goto copy_buffer;
+
+	if (*offset > 0)
+		*offset = 0;
+
+	rets = mei_cl_read_start(cl, length, file);
+	if (rets && rets != -EBUSY) {
+		cl_dbg(dev, cl, "mei start read failure status = %zd\n", rets);
+		goto out;
+	}
+
+	if (nonblock) {
+		rets = -EAGAIN;
+		goto out;
+	}
+
+	mutex_unlock(&dev->device_lock);
+	if (wait_event_interruptible(cl->rx_wait,
+				     mei_cl_read_cb(cl, file) ||
+				     !mei_cl_is_connected(cl))) {
+		if (signal_pending(current))
+			return -EINTR;
+		return -ERESTARTSYS;
+	}
+	mutex_lock(&dev->device_lock);
+
+	if (!mei_cl_is_connected(cl)) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	cb = mei_cl_read_cb(cl, file);
+	if (!cb) {
+		rets = 0;
+		goto out;
+	}
+
+copy_buffer:
+	/* now copy the data to user space */
+	if (cb->status) {
+		rets = cb->status;
+		cl_dbg(dev, cl, "read operation failed %zd\n", rets);
+		goto free;
+	}
+
+	cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n",
+	       cb->buf.size, cb->buf_idx, *offset);
+	if (*offset >= cb->buf_idx) {
+		rets = 0;
+		goto free;
+	}
+
+	/* length is being truncated to PAGE_SIZE,
+	 * however buf_idx may point beyond that */
+	length = min_t(size_t, length, cb->buf_idx - *offset);
+
+	if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
+		dev_dbg(dev->dev, "failed to copy data to userland\n");
+		rets = -EFAULT;
+		goto free;
+	}
+
+	rets = length;
+	*offset += length;
+	/* not all data was read, keep the cb */
+	if (*offset < cb->buf_idx)
+		goto out;
+
+free:
+	mei_cl_del_rd_completed(cl, cb);
+	*offset = 0;
+
+out:
+	cl_dbg(dev, cl, "end mei read rets = %zd\n", rets);
+	mutex_unlock(&dev->device_lock);
+	return rets;
+}
+
+/**
+ * mei_cl_vtag_by_fp - obtain the vtag by file pointer
+ *
+ * @cl: host client
+ * @fp: pointer to file structure
+ *
+ * Return: vtag value on success, otherwise 0
+ */
+static u8 mei_cl_vtag_by_fp(const struct mei_cl *cl, const struct file *fp)
+{
+	struct mei_cl_vtag *cl_vtag;
+
+	if (!fp)
+		return 0;
+
+	list_for_each_entry(cl_vtag, &cl->vtag_map, list)
+		if (cl_vtag->fp == fp)
+			return cl_vtag->vtag;
+	return 0;
+}
+
+/**
+ * mei_write - the write function.
+ *
+ * @file: pointer to file structure
+ * @ubuf: pointer to user buffer
+ * @length: buffer length
+ * @offset: data offset in buffer
+ *
+ * Return: >=0 data length on success , <0 on error
+ */
+static ssize_t mei_write(struct file *file, const char __user *ubuf,
+			 size_t length, loff_t *offset)
+{
+	struct mei_cl *cl = file->private_data;
+	struct mei_cl_cb *cb;
+	struct mei_device *dev;
+	ssize_t rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->device_lock);
+
+	if (dev->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	if (!mei_cl_is_connected(cl)) {
+		cl_err(dev, cl, "is not connected");
+		rets = -ENODEV;
+		goto out;
+	}
+
+	if (!mei_me_cl_is_active(cl->me_cl)) {
+		rets = -ENOTTY;
+		goto out;
+	}
+
+	if (length > mei_cl_mtu(cl)) {
+		rets = -EFBIG;
+		goto out;
+	}
+
+	if (length == 0) {
+		rets = 0;
+		goto out;
+	}
+
+	while (cl->tx_cb_queued >= dev->tx_queue_limit) {
+		if (file->f_flags & O_NONBLOCK) {
+			rets = -EAGAIN;
+			goto out;
+		}
+		mutex_unlock(&dev->device_lock);
+		rets = wait_event_interruptible(cl->tx_wait,
+				cl->writing_state == MEI_WRITE_COMPLETE ||
+				(!mei_cl_is_connected(cl)));
+		mutex_lock(&dev->device_lock);
+		if (rets) {
+			if (signal_pending(current))
+				rets = -EINTR;
+			goto out;
+		}
+		if (!mei_cl_is_connected(cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+	}
+
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
+	cb->vtag = mei_cl_vtag_by_fp(cl, file);
+
+	rets = copy_from_user(cb->buf.data, ubuf, length);
+	if (rets) {
+		dev_dbg(dev->dev, "failed to copy data from userland\n");
+		rets = -EFAULT;
+		mei_io_cb_free(cb);
+		goto out;
+	}
+
+	rets = mei_cl_write(cl, cb);
+out:
+	mutex_unlock(&dev->device_lock);
+	return rets;
+}
+
+/**
+ * mei_ioctl_connect_client - the connect to fw client IOCTL function
+ *
+ * @file: private data of the file object
+ * @in_client_uuid: requested UUID for connection
+ * @client: IOCTL connect data, output parameters
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int mei_ioctl_connect_client(struct file *file,
+				    const uuid_le *in_client_uuid,
+				    struct mei_client *client)
+{
+	struct mei_device *dev;
+	struct mei_me_client *me_cl;
+	struct mei_cl *cl;
+	int rets;
+
+	cl = file->private_data;
+	dev = cl->dev;
+
+	if (cl->state != MEI_FILE_INITIALIZING &&
+	    cl->state != MEI_FILE_DISCONNECTED)
+		return  -EBUSY;
+
+	/* find ME client we're trying to connect to */
+	me_cl = mei_me_cl_by_uuid(dev, in_client_uuid);
+	if (!me_cl) {
+		dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
+			in_client_uuid);
+		rets = -ENOTTY;
+		goto end;
+	}
+
+	if (me_cl->props.fixed_address) {
+		bool forbidden = dev->override_fixed_address ?
+			 !dev->allow_fixed_address : !dev->hbm_f_fa_supported;
+		if (forbidden) {
+			dev_dbg(dev->dev, "Connection forbidden to FW Client UUID = %pUl\n",
+				in_client_uuid);
+			rets = -ENOTTY;
+			goto end;
+		}
+	}
+
+	dev_dbg(dev->dev, "Connect to FW Client ID = %d\n",
+			me_cl->client_id);
+	dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n",
+			me_cl->props.protocol_version);
+	dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n",
+			me_cl->props.max_msg_length);
+
+	/* prepare the output buffer */
+	client->max_msg_length = me_cl->props.max_msg_length;
+	client->protocol_version = me_cl->props.protocol_version;
+	dev_dbg(dev->dev, "Can connect?\n");
+
+	rets = mei_cl_connect(cl, me_cl, file);
+
+end:
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_vt_support_check - check if client support vtags
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @dev: mei_device
+ * @uuid: client UUID
+ *
+ * Return:
+ *	0 - supported
+ *	-ENOTTY - no such client
+ *	-EOPNOTSUPP - vtags are not supported by client
+ */
+static int mei_vt_support_check(struct mei_device *dev, const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+	int ret;
+
+	if (!dev->hbm_f_vt_supported)
+		return -EOPNOTSUPP;
+
+	me_cl = mei_me_cl_by_uuid(dev, uuid);
+	if (!me_cl) {
+		dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
+			uuid);
+		return -ENOTTY;
+	}
+	ret = me_cl->props.vt_supported ? 0 : -EOPNOTSUPP;
+	mei_me_cl_put(me_cl);
+
+	return ret;
+}
+
+/**
+ * mei_ioctl_connect_vtag - connect to fw client with vtag IOCTL function
+ *
+ * @file: private data of the file object
+ * @in_client_uuid: requested UUID for connection
+ * @client: IOCTL connect data, output parameters
+ * @vtag: vm tag
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int mei_ioctl_connect_vtag(struct file *file,
+				  const uuid_le *in_client_uuid,
+				  struct mei_client *client,
+				  u8 vtag)
+{
+	struct mei_device *dev;
+	struct mei_cl *cl;
+	struct mei_cl *pos;
+	struct mei_cl_vtag *cl_vtag;
+
+	cl = file->private_data;
+	dev = cl->dev;
+
+	dev_dbg(dev->dev, "FW Client %pUl vtag %d\n", in_client_uuid, vtag);
+
+	switch (cl->state) {
+	case MEI_FILE_DISCONNECTED:
+		if (mei_cl_vtag_by_fp(cl, file) != vtag) {
+			dev_err(dev->dev, "reconnect with different vtag\n");
+			return -EINVAL;
+		}
+		break;
+	case MEI_FILE_INITIALIZING:
+		/* malicious connect from another thread may push vtag */
+		if (!IS_ERR(mei_cl_fp_by_vtag(cl, vtag))) {
+			dev_err(dev->dev, "vtag already filled\n");
+			return -EINVAL;
+		}
+
+		list_for_each_entry(pos, &dev->file_list, link) {
+			if (pos == cl)
+				continue;
+			if (!pos->me_cl)
+				continue;
+
+			/* only search for same UUID */
+			if (uuid_le_cmp(*mei_cl_uuid(pos), *in_client_uuid))
+				continue;
+
+			/* if tag already exist try another fp */
+			if (!IS_ERR(mei_cl_fp_by_vtag(pos, vtag)))
+				continue;
+
+			/* replace cl with acquired one */
+			dev_dbg(dev->dev, "replacing with existing cl\n");
+			mei_cl_unlink(cl);
+			kfree(cl);
+			file->private_data = pos;
+			cl = pos;
+			break;
+		}
+
+		cl_vtag = mei_cl_vtag_alloc(file, vtag);
+		if (IS_ERR(cl_vtag))
+			return -ENOMEM;
+
+		list_add_tail(&cl_vtag->list, &cl->vtag_map);
+		break;
+	default:
+		return -EBUSY;
+	}
+
+	while (cl->state != MEI_FILE_INITIALIZING &&
+	       cl->state != MEI_FILE_DISCONNECTED &&
+	       cl->state != MEI_FILE_CONNECTED) {
+		mutex_unlock(&dev->device_lock);
+		wait_event_timeout(cl->wait,
+				   (cl->state == MEI_FILE_CONNECTED ||
+				    cl->state == MEI_FILE_DISCONNECTED ||
+				    cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
+				    cl->state == MEI_FILE_DISCONNECT_REPLY),
+				   mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+		mutex_lock(&dev->device_lock);
+	}
+
+	if (!mei_cl_is_connected(cl))
+		return mei_ioctl_connect_client(file, in_client_uuid, client);
+
+	client->max_msg_length = cl->me_cl->props.max_msg_length;
+	client->protocol_version = cl->me_cl->props.protocol_version;
+
+	return 0;
+}
+
+/**
+ * mei_ioctl_client_notify_request -
+ *     propagate event notification request to client
+ *
+ * @file: pointer to file structure
+ * @request: 0 - disable, 1 - enable
+ *
+ * Return: 0 on success , <0 on error
+ */
+static int mei_ioctl_client_notify_request(const struct file *file, u32 request)
+{
+	struct mei_cl *cl = file->private_data;
+
+	if (request != MEI_HBM_NOTIFICATION_START &&
+	    request != MEI_HBM_NOTIFICATION_STOP)
+		return -EINVAL;
+
+	return mei_cl_notify_request(cl, file, (u8)request);
+}
+
+/**
+ * mei_ioctl_client_notify_get -  wait for notification request
+ *
+ * @file: pointer to file structure
+ * @notify_get: 0 - disable, 1 - enable
+ *
+ * Return: 0 on success , <0 on error
+ */
+static int mei_ioctl_client_notify_get(const struct file *file, u32 *notify_get)
+{
+	struct mei_cl *cl = file->private_data;
+	bool notify_ev;
+	bool block = (file->f_flags & O_NONBLOCK) == 0;
+	int rets;
+
+	rets = mei_cl_notify_get(cl, block, &notify_ev);
+	if (rets)
+		return rets;
+
+	*notify_get = notify_ev ? 1 : 0;
+	return 0;
+}
+
+/**
+ * mei_ioctl - the IOCTL function
+ *
+ * @file: pointer to file structure
+ * @cmd: ioctl command
+ * @data: pointer to mei message structure
+ *
+ * Return: 0 on success , <0 on error
+ */
+static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
+{
+	struct mei_device *dev;
+	struct mei_cl *cl = file->private_data;
+	struct mei_connect_client_data conn;
+	struct mei_connect_client_data_vtag conn_vtag;
+	const uuid_le *cl_uuid;
+	struct mei_client *props;
+	u8 vtag;
+	u32 notify_get, notify_req;
+	int rets;
+
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd);
+
+	mutex_lock(&dev->device_lock);
+	if (dev->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	switch (cmd) {
+	case IOCTL_MEI_CONNECT_CLIENT:
+		dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
+		if (copy_from_user(&conn, (char __user *)data, sizeof(conn))) {
+			dev_dbg(dev->dev, "failed to copy data from userland\n");
+			rets = -EFAULT;
+			goto out;
+		}
+		cl_uuid = &conn.in_client_uuid;
+		props = &conn.out_client_properties;
+		vtag = 0;
+
+		rets = mei_vt_support_check(dev, cl_uuid);
+		if (rets == -ENOTTY)
+			goto out;
+		if (!rets)
+			rets = mei_ioctl_connect_vtag(file, cl_uuid, props,
+						      vtag);
+		else
+			rets = mei_ioctl_connect_client(file, cl_uuid, props);
+		if (rets)
+			goto out;
+
+		/* if all is ok, copying the data back to user. */
+		if (copy_to_user((char __user *)data, &conn, sizeof(conn))) {
+			dev_dbg(dev->dev, "failed to copy data to userland\n");
+			rets = -EFAULT;
+			goto out;
+		}
+
+		break;
+
+	case IOCTL_MEI_CONNECT_CLIENT_VTAG:
+		dev_dbg(dev->dev, "IOCTL_MEI_CONNECT_CLIENT_VTAG\n");
+		if (copy_from_user(&conn_vtag, (char __user *)data,
+				   sizeof(conn_vtag))) {
+			dev_dbg(dev->dev, "failed to copy data from userland\n");
+			rets = -EFAULT;
+			goto out;
+		}
+
+		cl_uuid = &conn_vtag.connect.in_client_uuid;
+		props = &conn_vtag.out_client_properties;
+		vtag = conn_vtag.connect.vtag;
+
+		rets = mei_vt_support_check(dev, cl_uuid);
+		if (rets == -EOPNOTSUPP)
+			dev_dbg(dev->dev, "FW Client %pUl does not support vtags\n",
+				cl_uuid);
+		if (rets)
+			goto out;
+
+		if (!vtag) {
+			dev_dbg(dev->dev, "vtag can't be zero\n");
+			rets = -EINVAL;
+			goto out;
+		}
+
+		rets = mei_ioctl_connect_vtag(file, cl_uuid, props, vtag);
+		if (rets)
+			goto out;
+
+		/* if all is ok, copying the data back to user. */
+		if (copy_to_user((char __user *)data, &conn_vtag,
+				 sizeof(conn_vtag))) {
+			dev_dbg(dev->dev, "failed to copy data to userland\n");
+			rets = -EFAULT;
+			goto out;
+		}
+
+		break;
+
+	case IOCTL_MEI_NOTIFY_SET:
+		dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n");
+		if (copy_from_user(&notify_req,
+				   (char __user *)data, sizeof(notify_req))) {
+			dev_dbg(dev->dev, "failed to copy data from userland\n");
+			rets = -EFAULT;
+			goto out;
+		}
+		rets = mei_ioctl_client_notify_request(file, notify_req);
+		break;
+
+	case IOCTL_MEI_NOTIFY_GET:
+		dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n");
+		rets = mei_ioctl_client_notify_get(file, &notify_get);
+		if (rets)
+			goto out;
+
+		dev_dbg(dev->dev, "copy connect data to user\n");
+		if (copy_to_user((char __user *)data,
+				&notify_get, sizeof(notify_get))) {
+			dev_dbg(dev->dev, "failed to copy data to userland\n");
+			rets = -EFAULT;
+			goto out;
+
+		}
+		break;
+
+	default:
+		rets = -ENOIOCTLCMD;
+	}
+
+out:
+	mutex_unlock(&dev->device_lock);
+	return rets;
+}
+
+/**
+ * mei_poll - the poll function
+ *
+ * @file: pointer to file structure
+ * @wait: pointer to poll_table structure
+ *
+ * Return: poll mask
+ */
+static __poll_t mei_poll(struct file *file, poll_table *wait)
+{
+	__poll_t req_events = poll_requested_events(wait);
+	struct mei_cl *cl = file->private_data;
+	struct mei_device *dev;
+	__poll_t mask = 0;
+	bool notify_en;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return EPOLLERR;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->device_lock);
+
+	notify_en = cl->notify_en && (req_events & EPOLLPRI);
+
+	if (dev->dev_state != MEI_DEV_ENABLED ||
+	    !mei_cl_is_connected(cl)) {
+		mask = EPOLLERR;
+		goto out;
+	}
+
+	if (notify_en) {
+		poll_wait(file, &cl->ev_wait, wait);
+		if (cl->notify_ev)
+			mask |= EPOLLPRI;
+	}
+
+	if (req_events & (EPOLLIN | EPOLLRDNORM)) {
+		poll_wait(file, &cl->rx_wait, wait);
+
+		if (mei_cl_read_cb(cl, file))
+			mask |= EPOLLIN | EPOLLRDNORM;
+		else
+			mei_cl_read_start(cl, mei_cl_mtu(cl), file);
+	}
+
+	if (req_events & (EPOLLOUT | EPOLLWRNORM)) {
+		poll_wait(file, &cl->tx_wait, wait);
+		if (cl->tx_cb_queued < dev->tx_queue_limit)
+			mask |= EPOLLOUT | EPOLLWRNORM;
+	}
+
+out:
+	mutex_unlock(&dev->device_lock);
+	return mask;
+}
+
+/**
+ * mei_cl_is_write_queued - check if the client has pending writes.
+ *
+ * @cl: writing host client
+ *
+ * Return: true if client is writing, false otherwise.
+ */
+static bool mei_cl_is_write_queued(struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+	struct mei_cl_cb *cb;
+
+	list_for_each_entry(cb, &dev->write_list, list)
+		if (cb->cl == cl)
+			return true;
+	list_for_each_entry(cb, &dev->write_waiting_list, list)
+		if (cb->cl == cl)
+			return true;
+	return false;
+}
+
+/**
+ * mei_fsync - the fsync handler
+ *
+ * @fp:       pointer to file structure
+ * @start:    unused
+ * @end:      unused
+ * @datasync: unused
+ *
+ * Return: 0 on success, -ENODEV if client is not connected
+ */
+static int mei_fsync(struct file *fp, loff_t start, loff_t end, int datasync)
+{
+	struct mei_cl *cl = fp->private_data;
+	struct mei_device *dev;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->device_lock);
+
+	if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	while (mei_cl_is_write_queued(cl)) {
+		mutex_unlock(&dev->device_lock);
+		rets = wait_event_interruptible(cl->tx_wait,
+				cl->writing_state == MEI_WRITE_COMPLETE ||
+				!mei_cl_is_connected(cl));
+		mutex_lock(&dev->device_lock);
+		if (rets) {
+			if (signal_pending(current))
+				rets = -EINTR;
+			goto out;
+		}
+		if (!mei_cl_is_connected(cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+	}
+	rets = 0;
+out:
+	mutex_unlock(&dev->device_lock);
+	return rets;
+}
+
+/**
+ * mei_fasync - asynchronous io support
+ *
+ * @fd: file descriptor
+ * @file: pointer to file structure
+ * @band: band bitmap
+ *
+ * Return: negative on error,
+ *         0 if it did no changes,
+ *         and positive a process was added or deleted
+ */
+static int mei_fasync(int fd, struct file *file, int band)
+{
+
+	struct mei_cl *cl = file->private_data;
+
+	if (!mei_cl_is_connected(cl))
+		return -ENODEV;
+
+	return fasync_helper(fd, file, band, &cl->ev_async);
+}
+
+/**
+ * trc_show - mei device trc attribute show method
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t trc_show(struct device *device,
+			struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	u32 trc;
+	int ret;
+
+	ret = mei_trc_status(dev, &trc);
+	if (ret)
+		return ret;
+	return sprintf(buf, "%08X\n", trc);
+}
+static DEVICE_ATTR_RO(trc);
+
+/**
+ * fw_status_show - mei device fw_status attribute show method
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t fw_status_show(struct device *device,
+		struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	struct mei_fw_status fw_status;
+	int err, i;
+	ssize_t cnt = 0;
+
+	mutex_lock(&dev->device_lock);
+	err = mei_fw_status(dev, &fw_status);
+	mutex_unlock(&dev->device_lock);
+	if (err) {
+		dev_err(device, "read fw_status error = %d\n", err);
+		return err;
+	}
+
+	for (i = 0; i < fw_status.count; i++)
+		cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n",
+				fw_status.status[i]);
+	return cnt;
+}
+static DEVICE_ATTR_RO(fw_status);
+
+/**
+ * hbm_ver_show - display HBM protocol version negotiated with FW
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t hbm_ver_show(struct device *device,
+			    struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	struct hbm_version ver;
+
+	mutex_lock(&dev->device_lock);
+	ver = dev->version;
+	mutex_unlock(&dev->device_lock);
+
+	return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version);
+}
+static DEVICE_ATTR_RO(hbm_ver);
+
+/**
+ * hbm_ver_drv_show - display HBM protocol version advertised by driver
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t hbm_ver_drv_show(struct device *device,
+				struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION);
+}
+static DEVICE_ATTR_RO(hbm_ver_drv);
+
+static ssize_t tx_queue_limit_show(struct device *device,
+				   struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	u8 size = 0;
+
+	mutex_lock(&dev->device_lock);
+	size = dev->tx_queue_limit;
+	mutex_unlock(&dev->device_lock);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", size);
+}
+
+static ssize_t tx_queue_limit_store(struct device *device,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	u8 limit;
+	unsigned int inp;
+	int err;
+
+	err = kstrtouint(buf, 10, &inp);
+	if (err)
+		return err;
+	if (inp > MEI_TX_QUEUE_LIMIT_MAX || inp < MEI_TX_QUEUE_LIMIT_MIN)
+		return -EINVAL;
+	limit = inp;
+
+	mutex_lock(&dev->device_lock);
+	dev->tx_queue_limit = limit;
+	mutex_unlock(&dev->device_lock);
+
+	return count;
+}
+static DEVICE_ATTR_RW(tx_queue_limit);
+
+/**
+ * fw_ver_show - display ME FW version
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t fw_ver_show(struct device *device,
+			   struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	struct mei_fw_version *ver;
+	ssize_t cnt = 0;
+	int i;
+
+	ver = dev->fw_ver;
+
+	for (i = 0; i < MEI_MAX_FW_VER_BLOCKS; i++)
+		cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%u:%u.%u.%u.%u\n",
+				 ver[i].platform, ver[i].major, ver[i].minor,
+				 ver[i].hotfix, ver[i].buildno);
+	return cnt;
+}
+static DEVICE_ATTR_RO(fw_ver);
+
+/**
+ * dev_state_show - display device state
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t dev_state_show(struct device *device,
+			      struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	enum mei_dev_state dev_state;
+
+	mutex_lock(&dev->device_lock);
+	dev_state = dev->dev_state;
+	mutex_unlock(&dev->device_lock);
+
+	return sprintf(buf, "%s", mei_dev_state_str(dev_state));
+}
+static DEVICE_ATTR_RO(dev_state);
+
+/**
+ * dev_set_devstate: set to new device state and notify sysfs file.
+ *
+ * @dev: mei_device
+ * @state: new device state
+ */
+void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state)
+{
+	struct device *clsdev;
+
+	if (dev->dev_state == state)
+		return;
+
+	dev->dev_state = state;
+
+	clsdev = class_find_device_by_devt(mei_class, dev->cdev.dev);
+	if (clsdev) {
+		sysfs_notify(&clsdev->kobj, NULL, "dev_state");
+		put_device(clsdev);
+	}
+}
+
+/**
+ * kind_show - display device kind
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf: char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t kind_show(struct device *device,
+			 struct device_attribute *attr, char *buf)
+{
+	struct mei_device *dev = dev_get_drvdata(device);
+	ssize_t ret;
+
+	if (dev->kind)
+		ret = sprintf(buf, "%s\n", dev->kind);
+	else
+		ret = sprintf(buf, "%s\n", "mei");
+
+	return ret;
+}
+static DEVICE_ATTR_RO(kind);
+
+static struct attribute *mei_attrs[] = {
+	&dev_attr_fw_status.attr,
+	&dev_attr_hbm_ver.attr,
+	&dev_attr_hbm_ver_drv.attr,
+	&dev_attr_tx_queue_limit.attr,
+	&dev_attr_fw_ver.attr,
+	&dev_attr_dev_state.attr,
+	&dev_attr_trc.attr,
+	&dev_attr_kind.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(mei);
+
+/*
+ * file operations structure will be used for mei char device.
+ */
+static const struct file_operations mei_fops = {
+	.owner = THIS_MODULE,
+	.read = mei_read,
+	.unlocked_ioctl = mei_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+	.open = mei_open,
+	.release = mei_release,
+	.write = mei_write,
+	.poll = mei_poll,
+	.fsync = mei_fsync,
+	.fasync = mei_fasync,
+	.llseek = no_llseek
+};
+
+/**
+ * mei_minor_get - obtain next free device minor number
+ *
+ * @dev:  device pointer
+ *
+ * Return: allocated minor, or -ENOSPC if no free minor left
+ */
+static int mei_minor_get(struct mei_device *dev)
+{
+	int ret;
+
+	mutex_lock(&mei_minor_lock);
+	ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL);
+	if (ret >= 0)
+		dev->minor = ret;
+	else if (ret == -ENOSPC)
+		dev_err(dev->dev, "too many mei devices\n");
+
+	mutex_unlock(&mei_minor_lock);
+	return ret;
+}
+
+/**
+ * mei_minor_free - mark device minor number as free
+ *
+ * @dev:  device pointer
+ */
+static void mei_minor_free(struct mei_device *dev)
+{
+	mutex_lock(&mei_minor_lock);
+	idr_remove(&mei_idr, dev->minor);
+	mutex_unlock(&mei_minor_lock);
+}
+
+int mei_register(struct mei_device *dev, struct device *parent)
+{
+	struct device *clsdev; /* class device */
+	int ret, devno;
+
+	ret = mei_minor_get(dev);
+	if (ret < 0)
+		return ret;
+
+	/* Fill in the data structures */
+	devno = MKDEV(MAJOR(mei_devt), dev->minor);
+	cdev_init(&dev->cdev, &mei_fops);
+	dev->cdev.owner = parent->driver->owner;
+
+	/* Add the device */
+	ret = cdev_add(&dev->cdev, devno, 1);
+	if (ret) {
+		dev_err(parent, "unable to add device %d:%d\n",
+			MAJOR(mei_devt), dev->minor);
+		goto err_dev_add;
+	}
+
+	clsdev = device_create_with_groups(mei_class, parent, devno,
+					   dev, mei_groups,
+					   "mei%d", dev->minor);
+
+	if (IS_ERR(clsdev)) {
+		dev_err(parent, "unable to create device %d:%d\n",
+			MAJOR(mei_devt), dev->minor);
+		ret = PTR_ERR(clsdev);
+		goto err_dev_create;
+	}
+
+	mei_dbgfs_register(dev, dev_name(clsdev));
+
+	return 0;
+
+err_dev_create:
+	cdev_del(&dev->cdev);
+err_dev_add:
+	mei_minor_free(dev);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_register);
+
+void mei_deregister(struct mei_device *dev)
+{
+	int devno;
+
+	devno = dev->cdev.dev;
+	cdev_del(&dev->cdev);
+
+	mei_dbgfs_deregister(dev);
+
+	device_destroy(mei_class, devno);
+
+	mei_minor_free(dev);
+}
+EXPORT_SYMBOL_GPL(mei_deregister);
+
+static int __init mei_init(void)
+{
+	int ret;
+
+	mei_class = class_create(THIS_MODULE, "mei");
+	if (IS_ERR(mei_class)) {
+		pr_err("couldn't create class\n");
+		ret = PTR_ERR(mei_class);
+		goto err;
+	}
+
+	ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei");
+	if (ret < 0) {
+		pr_err("unable to allocate char dev region\n");
+		goto err_class;
+	}
+
+	ret = mei_cl_bus_init();
+	if (ret < 0) {
+		pr_err("unable to initialize bus\n");
+		goto err_chrdev;
+	}
+
+	return 0;
+
+err_chrdev:
+	unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
+err_class:
+	class_destroy(mei_class);
+err:
+	return ret;
+}
+
+static void __exit mei_exit(void)
+{
+	unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
+	class_destroy(mei_class);
+	mei_cl_bus_exit();
+}
+
+module_init(mei_init);
+module_exit(mei_exit);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
+MODULE_LICENSE("GPL v2");
+
diff --git a/drivers/misc/mei/mei-trace.c b/drivers/misc/mei/mei-trace.c
new file mode 100644
index 000000000..48d4c4fce
--- /dev/null
+++ b/drivers/misc/mei/mei-trace.c
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2015-2016, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+#include <linux/module.h>
+
+/* sparse doesn't like tracepoint macros */
+#ifndef __CHECKER__
+#define CREATE_TRACE_POINTS
+#include "mei-trace.h"
+
+EXPORT_TRACEPOINT_SYMBOL(mei_reg_read);
+EXPORT_TRACEPOINT_SYMBOL(mei_reg_write);
+EXPORT_TRACEPOINT_SYMBOL(mei_pci_cfg_read);
+#endif /* __CHECKER__ */
diff --git a/drivers/misc/mei/mei-trace.h b/drivers/misc/mei/mei-trace.h
new file mode 100644
index 000000000..df758033d
--- /dev/null
+++ b/drivers/misc/mei/mei-trace.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2015-2016, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#if !defined(_MEI_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
+#define _MEI_TRACE_H_
+
+#include <linux/stringify.h>
+#include <linux/types.h>
+#include <linux/tracepoint.h>
+
+#include <linux/device.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mei
+
+TRACE_EVENT(mei_reg_read,
+	TP_PROTO(const struct device *dev, const char *reg, u32 offs, u32 val),
+	TP_ARGS(dev, reg, offs, val),
+	TP_STRUCT__entry(
+		__string(dev, dev_name(dev))
+		__field(const char *, reg)
+		__field(u32, offs)
+		__field(u32, val)
+	),
+	TP_fast_assign(
+		__assign_str(dev, dev_name(dev))
+		__entry->reg  = reg;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%s] read %s:[%#x] = %#x",
+		  __get_str(dev), __entry->reg, __entry->offs, __entry->val)
+);
+
+TRACE_EVENT(mei_reg_write,
+	TP_PROTO(const struct device *dev, const char *reg, u32 offs, u32 val),
+	TP_ARGS(dev, reg, offs, val),
+	TP_STRUCT__entry(
+		__string(dev, dev_name(dev))
+		__field(const char *, reg)
+		__field(u32, offs)
+		__field(u32, val)
+	),
+	TP_fast_assign(
+		__assign_str(dev, dev_name(dev))
+		__entry->reg = reg;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%s] write %s[%#x] = %#x",
+		  __get_str(dev), __entry->reg,  __entry->offs, __entry->val)
+);
+
+TRACE_EVENT(mei_pci_cfg_read,
+	TP_PROTO(const struct device *dev, const char *reg, u32 offs, u32 val),
+	TP_ARGS(dev, reg, offs, val),
+	TP_STRUCT__entry(
+		__string(dev, dev_name(dev))
+		__field(const char *, reg)
+		__field(u32, offs)
+		__field(u32, val)
+	),
+	TP_fast_assign(
+		__assign_str(dev, dev_name(dev))
+		__entry->reg  = reg;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%s] pci cfg read %s:[%#x] = %#x",
+		  __get_str(dev), __entry->reg, __entry->offs, __entry->val)
+);
+
+#endif /* _MEI_TRACE_H_ */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE mei-trace
+#include <trace/define_trace.h>
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
new file mode 100644
index 000000000..2f4cc1a8a
--- /dev/null
+++ b/drivers/misc/mei/mei_dev.h
@@ -0,0 +1,810 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#ifndef _MEI_DEV_H_
+#define _MEI_DEV_H_
+
+#include <linux/types.h>
+#include <linux/cdev.h>
+#include <linux/poll.h>
+#include <linux/mei.h>
+#include <linux/mei_cl_bus.h>
+
+#include "hw.h"
+#include "hbm.h"
+
+#define MEI_SLOT_SIZE             sizeof(u32)
+#define MEI_RD_MSG_BUF_SIZE       (128 * MEI_SLOT_SIZE)
+
+/*
+ * Number of Maximum MEI Clients
+ */
+#define MEI_CLIENTS_MAX 256
+
+/*
+ * maximum number of consecutive resets
+ */
+#define MEI_MAX_CONSEC_RESET  3
+
+/*
+ * Number of File descriptors/handles
+ * that can be opened to the driver.
+ *
+ * Limit to 255: 256 Total Clients
+ * minus internal client for MEI Bus Messages
+ */
+#define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
+
+/* File state */
+enum file_state {
+	MEI_FILE_UNINITIALIZED = 0,
+	MEI_FILE_INITIALIZING,
+	MEI_FILE_CONNECTING,
+	MEI_FILE_CONNECTED,
+	MEI_FILE_DISCONNECTING,
+	MEI_FILE_DISCONNECT_REPLY,
+	MEI_FILE_DISCONNECT_REQUIRED,
+	MEI_FILE_DISCONNECTED,
+};
+
+/* MEI device states */
+enum mei_dev_state {
+	MEI_DEV_INITIALIZING = 0,
+	MEI_DEV_INIT_CLIENTS,
+	MEI_DEV_ENABLED,
+	MEI_DEV_RESETTING,
+	MEI_DEV_DISABLED,
+	MEI_DEV_POWER_DOWN,
+	MEI_DEV_POWER_UP
+};
+
+const char *mei_dev_state_str(int state);
+
+enum mei_file_transaction_states {
+	MEI_IDLE,
+	MEI_WRITING,
+	MEI_WRITE_COMPLETE,
+};
+
+/**
+ * enum mei_cb_file_ops  - file operation associated with the callback
+ * @MEI_FOP_READ:       read
+ * @MEI_FOP_WRITE:      write
+ * @MEI_FOP_CONNECT:    connect
+ * @MEI_FOP_DISCONNECT: disconnect
+ * @MEI_FOP_DISCONNECT_RSP: disconnect response
+ * @MEI_FOP_NOTIFY_START:   start notification
+ * @MEI_FOP_NOTIFY_STOP:    stop notification
+ */
+enum mei_cb_file_ops {
+	MEI_FOP_READ = 0,
+	MEI_FOP_WRITE,
+	MEI_FOP_CONNECT,
+	MEI_FOP_DISCONNECT,
+	MEI_FOP_DISCONNECT_RSP,
+	MEI_FOP_NOTIFY_START,
+	MEI_FOP_NOTIFY_STOP,
+};
+
+/**
+ * enum mei_cl_io_mode - io mode between driver and fw
+ *
+ * @MEI_CL_IO_TX_BLOCKING: send is blocking
+ * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
+ *
+ * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
+ */
+enum mei_cl_io_mode {
+	MEI_CL_IO_TX_BLOCKING = BIT(0),
+	MEI_CL_IO_TX_INTERNAL = BIT(1),
+
+	MEI_CL_IO_RX_NONBLOCK = BIT(2),
+};
+
+/*
+ * Intel MEI message data struct
+ */
+struct mei_msg_data {
+	size_t size;
+	unsigned char *data;
+};
+
+/**
+ * struct mei_dma_dscr - dma address descriptor
+ *
+ * @vaddr: dma buffer virtual address
+ * @daddr: dma buffer physical address
+ * @size : dma buffer size
+ */
+struct mei_dma_dscr {
+	void *vaddr;
+	dma_addr_t daddr;
+	size_t size;
+};
+
+/* Maximum number of processed FW status registers */
+#define MEI_FW_STATUS_MAX 6
+/* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
+#define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
+
+
+/*
+ * struct mei_fw_status - storage of FW status data
+ *
+ * @count: number of actually available elements in array
+ * @status: FW status registers
+ */
+struct mei_fw_status {
+	int count;
+	u32 status[MEI_FW_STATUS_MAX];
+};
+
+/**
+ * struct mei_me_client - representation of me (fw) client
+ *
+ * @list: link in me client list
+ * @refcnt: struct reference count
+ * @props: client properties
+ * @client_id: me client id
+ * @tx_flow_ctrl_creds: flow control credits
+ * @connect_count: number connections to this client
+ * @bus_added: added to bus
+ */
+struct mei_me_client {
+	struct list_head list;
+	struct kref refcnt;
+	struct mei_client_properties props;
+	u8 client_id;
+	u8 tx_flow_ctrl_creds;
+	u8 connect_count;
+	u8 bus_added;
+};
+
+
+struct mei_cl;
+
+/**
+ * struct mei_cl_cb - file operation callback structure
+ *
+ * @list: link in callback queue
+ * @cl: file client who is running this operation
+ * @fop_type: file operation type
+ * @buf: buffer for data associated with the callback
+ * @buf_idx: last read index
+ * @vtag: virtual tag
+ * @fp: pointer to file structure
+ * @status: io status of the cb
+ * @internal: communication between driver and FW flag
+ * @blocking: transmission blocking mode
+ */
+struct mei_cl_cb {
+	struct list_head list;
+	struct mei_cl *cl;
+	enum mei_cb_file_ops fop_type;
+	struct mei_msg_data buf;
+	size_t buf_idx;
+	u8 vtag;
+	const struct file *fp;
+	int status;
+	u32 internal:1;
+	u32 blocking:1;
+};
+
+/**
+ * struct mei_cl_vtag - file pointer to vtag mapping structure
+ *
+ * @list: link in map queue
+ * @fp: file pointer
+ * @vtag: corresponding vtag
+ * @pending_read: the read is pending on this file
+ */
+struct mei_cl_vtag {
+	struct list_head list;
+	const struct file *fp;
+	u8 vtag;
+	u8 pending_read:1;
+};
+
+/**
+ * struct mei_cl - me client host representation
+ *    carried in file->private_data
+ *
+ * @link: link in the clients list
+ * @dev: mei parent device
+ * @state: file operation state
+ * @tx_wait: wait queue for tx completion
+ * @rx_wait: wait queue for rx completion
+ * @wait:  wait queue for management operation
+ * @ev_wait: notification wait queue
+ * @ev_async: event async notification
+ * @status: connection status
+ * @me_cl: fw client connected
+ * @fp: file associated with client
+ * @host_client_id: host id
+ * @vtag_map: vtag map
+ * @tx_flow_ctrl_creds: transmit flow credentials
+ * @rx_flow_ctrl_creds: receive flow credentials
+ * @timer_count:  watchdog timer for operation completion
+ * @notify_en: notification - enabled/disabled
+ * @notify_ev: pending notification event
+ * @tx_cb_queued: number of tx callbacks in queue
+ * @writing_state: state of the tx
+ * @rd_pending: pending read credits
+ * @rd_completed_lock: protects rd_completed queue
+ * @rd_completed: completed read
+ *
+ * @cldev: device on the mei client bus
+ */
+struct mei_cl {
+	struct list_head link;
+	struct mei_device *dev;
+	enum file_state state;
+	wait_queue_head_t tx_wait;
+	wait_queue_head_t rx_wait;
+	wait_queue_head_t wait;
+	wait_queue_head_t ev_wait;
+	struct fasync_struct *ev_async;
+	int status;
+	struct mei_me_client *me_cl;
+	const struct file *fp;
+	u8 host_client_id;
+	struct list_head vtag_map;
+	u8 tx_flow_ctrl_creds;
+	u8 rx_flow_ctrl_creds;
+	u8 timer_count;
+	u8 notify_en;
+	u8 notify_ev;
+	u8 tx_cb_queued;
+	enum mei_file_transaction_states writing_state;
+	struct list_head rd_pending;
+	spinlock_t rd_completed_lock; /* protects rd_completed queue */
+	struct list_head rd_completed;
+
+	struct mei_cl_device *cldev;
+};
+
+#define MEI_TX_QUEUE_LIMIT_DEFAULT 50
+#define MEI_TX_QUEUE_LIMIT_MAX 255
+#define MEI_TX_QUEUE_LIMIT_MIN 30
+
+/**
+ * struct mei_hw_ops - hw specific ops
+ *
+ * @host_is_ready    : query for host readiness
+ *
+ * @hw_is_ready      : query if hw is ready
+ * @hw_reset         : reset hw
+ * @hw_start         : start hw after reset
+ * @hw_config        : configure hw
+ *
+ * @fw_status        : get fw status registers
+ * @trc_status       : get trc status register
+ * @pg_state         : power gating state of the device
+ * @pg_in_transition : is device now in pg transition
+ * @pg_is_enabled    : is power gating enabled
+ *
+ * @intr_clear       : clear pending interrupts
+ * @intr_enable      : enable interrupts
+ * @intr_disable     : disable interrupts
+ * @synchronize_irq  : synchronize irqs
+ *
+ * @hbuf_free_slots  : query for write buffer empty slots
+ * @hbuf_is_ready    : query if write buffer is empty
+ * @hbuf_depth       : query for write buffer depth
+ *
+ * @write            : write a message to FW
+ *
+ * @rdbuf_full_slots : query how many slots are filled
+ *
+ * @read_hdr         : get first 4 bytes (header)
+ * @read             : read a buffer from the FW
+ */
+struct mei_hw_ops {
+
+	bool (*host_is_ready)(struct mei_device *dev);
+
+	bool (*hw_is_ready)(struct mei_device *dev);
+	int (*hw_reset)(struct mei_device *dev, bool enable);
+	int (*hw_start)(struct mei_device *dev);
+	int (*hw_config)(struct mei_device *dev);
+
+	int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
+	int (*trc_status)(struct mei_device *dev, u32 *trc);
+
+	enum mei_pg_state (*pg_state)(struct mei_device *dev);
+	bool (*pg_in_transition)(struct mei_device *dev);
+	bool (*pg_is_enabled)(struct mei_device *dev);
+
+	void (*intr_clear)(struct mei_device *dev);
+	void (*intr_enable)(struct mei_device *dev);
+	void (*intr_disable)(struct mei_device *dev);
+	void (*synchronize_irq)(struct mei_device *dev);
+
+	int (*hbuf_free_slots)(struct mei_device *dev);
+	bool (*hbuf_is_ready)(struct mei_device *dev);
+	u32 (*hbuf_depth)(const struct mei_device *dev);
+	int (*write)(struct mei_device *dev,
+		     const void *hdr, size_t hdr_len,
+		     const void *data, size_t data_len);
+
+	int (*rdbuf_full_slots)(struct mei_device *dev);
+
+	u32 (*read_hdr)(const struct mei_device *dev);
+	int (*read)(struct mei_device *dev,
+		     unsigned char *buf, unsigned long len);
+};
+
+/* MEI bus API*/
+void mei_cl_bus_rescan_work(struct work_struct *work);
+void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
+ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+		      unsigned int mode);
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
+		      unsigned int mode, unsigned long timeout);
+bool mei_cl_bus_rx_event(struct mei_cl *cl);
+bool mei_cl_bus_notify_event(struct mei_cl *cl);
+void mei_cl_bus_remove_devices(struct mei_device *bus);
+int mei_cl_bus_init(void);
+void mei_cl_bus_exit(void);
+
+/**
+ * enum mei_pg_event - power gating transition events
+ *
+ * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
+ * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
+ * @MEI_PG_EVENT_RECEIVED: the driver received pg event
+ * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
+ * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
+ */
+enum mei_pg_event {
+	MEI_PG_EVENT_IDLE,
+	MEI_PG_EVENT_WAIT,
+	MEI_PG_EVENT_RECEIVED,
+	MEI_PG_EVENT_INTR_WAIT,
+	MEI_PG_EVENT_INTR_RECEIVED,
+};
+
+/**
+ * enum mei_pg_state - device internal power gating state
+ *
+ * @MEI_PG_OFF: device is not power gated - it is active
+ * @MEI_PG_ON:  device is power gated - it is in lower power state
+ */
+enum mei_pg_state {
+	MEI_PG_OFF = 0,
+	MEI_PG_ON =  1,
+};
+
+const char *mei_pg_state_str(enum mei_pg_state state);
+
+/**
+ * struct mei_fw_version - MEI FW version struct
+ *
+ * @platform: platform identifier
+ * @major: major version field
+ * @minor: minor version field
+ * @buildno: build number version field
+ * @hotfix: hotfix number version field
+ */
+struct mei_fw_version {
+	u8 platform;
+	u8 major;
+	u16 minor;
+	u16 buildno;
+	u16 hotfix;
+};
+
+#define MEI_MAX_FW_VER_BLOCKS 3
+
+/**
+ * struct mei_device -  MEI private device struct
+ *
+ * @dev         : device on a bus
+ * @cdev        : character device
+ * @minor       : minor number allocated for device
+ *
+ * @write_list  : write pending list
+ * @write_waiting_list : write completion list
+ * @ctrl_wr_list : pending control write list
+ * @ctrl_rd_list : pending control read list
+ * @tx_queue_limit: tx queues per client linit
+ *
+ * @file_list   : list of opened handles
+ * @open_handle_count: number of opened handles
+ *
+ * @device_lock : big device lock
+ * @timer_work  : MEI timer delayed work (timeouts)
+ *
+ * @recvd_hw_ready : hw ready message received flag
+ *
+ * @wait_hw_ready : wait queue for receive HW ready message form FW
+ * @wait_pg     : wait queue for receive PG message from FW
+ * @wait_hbm_start : wait queue for receive HBM start message from FW
+ *
+ * @reset_count : number of consecutive resets
+ * @dev_state   : device state
+ * @hbm_state   : state of host bus message protocol
+ * @init_clients_timer : HBM init handshake timeout
+ *
+ * @pg_event    : power gating event
+ * @pg_domain   : runtime PM domain
+ *
+ * @rd_msg_buf  : control messages buffer
+ * @rd_msg_hdr  : read message header storage
+ * @rd_msg_hdr_count : how many dwords were already read from header
+ *
+ * @hbuf_is_ready : query if the host host/write buffer is ready
+ * @dr_dscr: DMA ring descriptors: TX, RX, and CTRL
+ *
+ * @version     : HBM protocol version in use
+ * @hbm_f_pg_supported  : hbm feature pgi protocol
+ * @hbm_f_dc_supported  : hbm feature dynamic clients
+ * @hbm_f_dot_supported : hbm feature disconnect on timeout
+ * @hbm_f_ev_supported  : hbm feature event notification
+ * @hbm_f_fa_supported  : hbm feature fixed address client
+ * @hbm_f_ie_supported  : hbm feature immediate reply to enum request
+ * @hbm_f_os_supported  : hbm feature support OS ver message
+ * @hbm_f_dr_supported  : hbm feature dma ring supported
+ * @hbm_f_vt_supported  : hbm feature vtag supported
+ * @hbm_f_cap_supported : hbm feature capabilities message supported
+ *
+ * @fw_ver : FW versions
+ *
+ * @fw_f_fw_ver_supported : fw feature: fw version supported
+ *
+ * @me_clients_rwsem: rw lock over me_clients list
+ * @me_clients  : list of FW clients
+ * @me_clients_map : FW clients bit map
+ * @host_clients_map : host clients id pool
+ *
+ * @allow_fixed_address: allow user space to connect a fixed client
+ * @override_fixed_address: force allow fixed address behavior
+ *
+ * @reset_work  : work item for the device reset
+ * @bus_rescan_work : work item for the bus rescan
+ *
+ * @device_list : mei client bus list
+ * @cl_bus_lock : client bus list lock
+ *
+ * @kind        : kind of mei device
+ *
+ * @dbgfs_dir   : debugfs mei root directory
+ *
+ * @ops:        : hw specific operations
+ * @hw          : hw specific data
+ */
+struct mei_device {
+	struct device *dev;
+	struct cdev cdev;
+	int minor;
+
+	struct list_head write_list;
+	struct list_head write_waiting_list;
+	struct list_head ctrl_wr_list;
+	struct list_head ctrl_rd_list;
+	u8 tx_queue_limit;
+
+	struct list_head file_list;
+	long open_handle_count;
+
+	struct mutex device_lock;
+	struct delayed_work timer_work;
+
+	bool recvd_hw_ready;
+	/*
+	 * waiting queue for receive message from FW
+	 */
+	wait_queue_head_t wait_hw_ready;
+	wait_queue_head_t wait_pg;
+	wait_queue_head_t wait_hbm_start;
+
+	/*
+	 * mei device  states
+	 */
+	unsigned long reset_count;
+	enum mei_dev_state dev_state;
+	enum mei_hbm_state hbm_state;
+	u16 init_clients_timer;
+
+	/*
+	 * Power Gating support
+	 */
+	enum mei_pg_event pg_event;
+#ifdef CONFIG_PM
+	struct dev_pm_domain pg_domain;
+#endif /* CONFIG_PM */
+
+	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
+	u32 rd_msg_hdr[MEI_RD_MSG_BUF_SIZE];
+	int rd_msg_hdr_count;
+
+	/* write buffer */
+	bool hbuf_is_ready;
+
+	struct mei_dma_dscr dr_dscr[DMA_DSCR_NUM];
+
+	struct hbm_version version;
+	unsigned int hbm_f_pg_supported:1;
+	unsigned int hbm_f_dc_supported:1;
+	unsigned int hbm_f_dot_supported:1;
+	unsigned int hbm_f_ev_supported:1;
+	unsigned int hbm_f_fa_supported:1;
+	unsigned int hbm_f_ie_supported:1;
+	unsigned int hbm_f_os_supported:1;
+	unsigned int hbm_f_dr_supported:1;
+	unsigned int hbm_f_vt_supported:1;
+	unsigned int hbm_f_cap_supported:1;
+
+	struct mei_fw_version fw_ver[MEI_MAX_FW_VER_BLOCKS];
+
+	unsigned int fw_f_fw_ver_supported:1;
+
+	struct rw_semaphore me_clients_rwsem;
+	struct list_head me_clients;
+	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
+	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
+
+	bool allow_fixed_address;
+	bool override_fixed_address;
+
+	struct work_struct reset_work;
+	struct work_struct bus_rescan_work;
+
+	/* List of bus devices */
+	struct list_head device_list;
+	struct mutex cl_bus_lock;
+
+	const char *kind;
+
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	struct dentry *dbgfs_dir;
+#endif /* CONFIG_DEBUG_FS */
+
+	const struct mei_hw_ops *ops;
+	char hw[] __aligned(sizeof(void *));
+};
+
+static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
+{
+	return msecs_to_jiffies(sec * MSEC_PER_SEC);
+}
+
+/**
+ * mei_data2slots - get slots number from a message length
+ *
+ * @length: size of the messages in bytes
+ *
+ * Return: number of slots
+ */
+static inline u32 mei_data2slots(size_t length)
+{
+	return DIV_ROUND_UP(length, MEI_SLOT_SIZE);
+}
+
+/**
+ * mei_hbm2slots - get slots number from a hbm message length
+ *                 length + size of the mei message header
+ *
+ * @length: size of the messages in bytes
+ *
+ * Return: number of slots
+ */
+static inline u32 mei_hbm2slots(size_t length)
+{
+	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, MEI_SLOT_SIZE);
+}
+
+/**
+ * mei_slots2data - get data in slots - bytes from slots
+ *
+ * @slots: number of available slots
+ *
+ * Return: number of bytes in slots
+ */
+static inline u32 mei_slots2data(int slots)
+{
+	return slots * MEI_SLOT_SIZE;
+}
+
+/*
+ * mei init function prototypes
+ */
+void mei_device_init(struct mei_device *dev,
+		     struct device *device,
+		     const struct mei_hw_ops *hw_ops);
+int mei_reset(struct mei_device *dev);
+int mei_start(struct mei_device *dev);
+int mei_restart(struct mei_device *dev);
+void mei_stop(struct mei_device *dev);
+void mei_cancel_work(struct mei_device *dev);
+
+void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state);
+
+int mei_dmam_ring_alloc(struct mei_device *dev);
+void mei_dmam_ring_free(struct mei_device *dev);
+bool mei_dma_ring_is_allocated(struct mei_device *dev);
+void mei_dma_ring_reset(struct mei_device *dev);
+void mei_dma_ring_read(struct mei_device *dev, unsigned char *buf, u32 len);
+void mei_dma_ring_write(struct mei_device *dev, unsigned char *buf, u32 len);
+u32 mei_dma_ring_empty_slots(struct mei_device *dev);
+
+/*
+ *  MEI interrupt functions prototype
+ */
+
+void mei_timer(struct work_struct *work);
+void mei_schedule_stall_timer(struct mei_device *dev);
+int mei_irq_read_handler(struct mei_device *dev,
+			 struct list_head *cmpl_list, s32 *slots);
+
+int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list);
+void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list);
+
+/*
+ * Register Access Function
+ */
+
+
+static inline int mei_hw_config(struct mei_device *dev)
+{
+	return dev->ops->hw_config(dev);
+}
+
+static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
+{
+	return dev->ops->pg_state(dev);
+}
+
+static inline bool mei_pg_in_transition(struct mei_device *dev)
+{
+	return dev->ops->pg_in_transition(dev);
+}
+
+static inline bool mei_pg_is_enabled(struct mei_device *dev)
+{
+	return dev->ops->pg_is_enabled(dev);
+}
+
+static inline int mei_hw_reset(struct mei_device *dev, bool enable)
+{
+	return dev->ops->hw_reset(dev, enable);
+}
+
+static inline int mei_hw_start(struct mei_device *dev)
+{
+	return dev->ops->hw_start(dev);
+}
+
+static inline void mei_clear_interrupts(struct mei_device *dev)
+{
+	dev->ops->intr_clear(dev);
+}
+
+static inline void mei_enable_interrupts(struct mei_device *dev)
+{
+	dev->ops->intr_enable(dev);
+}
+
+static inline void mei_disable_interrupts(struct mei_device *dev)
+{
+	dev->ops->intr_disable(dev);
+}
+
+static inline void mei_synchronize_irq(struct mei_device *dev)
+{
+	dev->ops->synchronize_irq(dev);
+}
+
+static inline bool mei_host_is_ready(struct mei_device *dev)
+{
+	return dev->ops->host_is_ready(dev);
+}
+static inline bool mei_hw_is_ready(struct mei_device *dev)
+{
+	return dev->ops->hw_is_ready(dev);
+}
+
+static inline bool mei_hbuf_is_ready(struct mei_device *dev)
+{
+	return dev->ops->hbuf_is_ready(dev);
+}
+
+static inline int mei_hbuf_empty_slots(struct mei_device *dev)
+{
+	return dev->ops->hbuf_free_slots(dev);
+}
+
+static inline u32 mei_hbuf_depth(const struct mei_device *dev)
+{
+	return dev->ops->hbuf_depth(dev);
+}
+
+static inline int mei_write_message(struct mei_device *dev,
+				    const void *hdr, size_t hdr_len,
+				    const void *data, size_t data_len)
+{
+	return dev->ops->write(dev, hdr, hdr_len, data, data_len);
+}
+
+static inline u32 mei_read_hdr(const struct mei_device *dev)
+{
+	return dev->ops->read_hdr(dev);
+}
+
+static inline void mei_read_slots(struct mei_device *dev,
+		     unsigned char *buf, unsigned long len)
+{
+	dev->ops->read(dev, buf, len);
+}
+
+static inline int mei_count_full_read_slots(struct mei_device *dev)
+{
+	return dev->ops->rdbuf_full_slots(dev);
+}
+
+static inline int mei_trc_status(struct mei_device *dev, u32 *trc)
+{
+	if (dev->ops->trc_status)
+		return dev->ops->trc_status(dev, trc);
+	return -EOPNOTSUPP;
+}
+
+static inline int mei_fw_status(struct mei_device *dev,
+				struct mei_fw_status *fw_status)
+{
+	return dev->ops->fw_status(dev, fw_status);
+}
+
+bool mei_hbuf_acquire(struct mei_device *dev);
+
+bool mei_write_is_idle(struct mei_device *dev);
+
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+void mei_dbgfs_register(struct mei_device *dev, const char *name);
+void mei_dbgfs_deregister(struct mei_device *dev);
+#else
+static inline void mei_dbgfs_register(struct mei_device *dev, const char *name) {}
+static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
+#endif /* CONFIG_DEBUG_FS */
+
+int mei_register(struct mei_device *dev, struct device *parent);
+void mei_deregister(struct mei_device *dev);
+
+#define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d dma=%1d ext=%1d internal=%1d comp=%1d"
+#define MEI_HDR_PRM(hdr)                  \
+	(hdr)->host_addr, (hdr)->me_addr, \
+	(hdr)->length, (hdr)->dma_ring, (hdr)->extended, \
+	(hdr)->internal, (hdr)->msg_complete
+
+ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
+/**
+ * mei_fw_status_str - fetch and convert fw status registers to printable string
+ *
+ * @dev: the device structure
+ * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
+ * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
+ *
+ * Return: number of bytes written or < 0 on failure
+ */
+static inline ssize_t mei_fw_status_str(struct mei_device *dev,
+					char *buf, size_t len)
+{
+	struct mei_fw_status fw_status;
+	int ret;
+
+	buf[0] = '\0';
+
+	ret = mei_fw_status(dev, &fw_status);
+	if (ret)
+		return ret;
+
+	ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);
+
+	return ret;
+}
+
+
+#endif
diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c
new file mode 100644
index 000000000..f2765d6b8
--- /dev/null
+++ b/drivers/misc/mei/pci-me.c
@@ -0,0 +1,539 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "client.h"
+#include "hw-me-regs.h"
+#include "hw-me.h"
+
+/* mei_pci_tbl - PCI Device ID Table */
+static const struct pci_device_id mei_me_pci_tbl[] = {
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82946GZ, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82G35, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82Q965, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82G965, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82GM965, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_82GME965, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_82Q35, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_82G33, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_82Q33, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_82X38, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_3200, MEI_ME_ICH_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_6, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_7, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_8, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_9, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9_10, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9M_1, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9M_2, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9M_3, MEI_ME_ICH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH9M_4, MEI_ME_ICH_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH10_1, MEI_ME_ICH10_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH10_2, MEI_ME_ICH10_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH10_3, MEI_ME_ICH10_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICH10_4, MEI_ME_ICH10_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_IBXPK_1, MEI_ME_PCH6_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_IBXPK_2, MEI_ME_PCH6_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CPT_1, MEI_ME_PCH_CPT_PBG_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_PBG_1, MEI_ME_PCH_CPT_PBG_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_PPT_1, MEI_ME_PCH7_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_PPT_2, MEI_ME_PCH7_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_PPT_3, MEI_ME_PCH7_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_LPT_H, MEI_ME_PCH8_SPS_4_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_LPT_W, MEI_ME_PCH8_SPS_4_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_LPT_LP, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_LPT_HR, MEI_ME_PCH8_SPS_4_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_WPT_LP, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_WPT_LP_2, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_2, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_3, MEI_ME_PCH8_ITOUCH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H, MEI_ME_PCH8_SPS_4_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_SPT_H_2, MEI_ME_PCH8_SPS_4_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_LBG, MEI_ME_PCH12_SPS_4_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_BXT_M, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_APL_I, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_DNV_IE, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_GLK, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_KBP, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_KBP_2, MEI_ME_PCH8_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_KBP_3, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CNP_LP, MEI_ME_PCH12_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CNP_LP_3, MEI_ME_PCH8_ITOUCH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CNP_H, MEI_ME_PCH12_SPS_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CNP_H_3, MEI_ME_PCH12_SPS_ITOUCH_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CMP_LP, MEI_ME_PCH12_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CMP_LP_3, MEI_ME_PCH8_ITOUCH_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CMP_V, MEI_ME_PCH12_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CMP_H, MEI_ME_PCH12_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CMP_H_3, MEI_ME_PCH8_ITOUCH_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICP_LP, MEI_ME_PCH12_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ICP_N, MEI_ME_PCH12_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_TGP_LP, MEI_ME_PCH15_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_TGP_H, MEI_ME_PCH15_SPS_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_JSP_N, MEI_ME_PCH15_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_MCC, MEI_ME_PCH15_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_MCC_4, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_CDF, MEI_ME_PCH8_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_EBG, MEI_ME_PCH15_SPS_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ADP_S, MEI_ME_PCH15_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ADP_LP, MEI_ME_PCH15_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ADP_P, MEI_ME_PCH15_CFG)},
+	{MEI_PCI_DEVICE(MEI_DEV_ID_ADP_N, MEI_ME_PCH15_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_RPL_S, MEI_ME_PCH15_CFG)},
+
+	{MEI_PCI_DEVICE(MEI_DEV_ID_MTL_M, MEI_ME_PCH15_CFG)},
+
+	/* required last entry */
+	{0, }
+};
+
+MODULE_DEVICE_TABLE(pci, mei_me_pci_tbl);
+
+#ifdef CONFIG_PM
+static inline void mei_me_set_pm_domain(struct mei_device *dev);
+static inline void mei_me_unset_pm_domain(struct mei_device *dev);
+#else
+static inline void mei_me_set_pm_domain(struct mei_device *dev) {}
+static inline void mei_me_unset_pm_domain(struct mei_device *dev) {}
+#endif /* CONFIG_PM */
+
+static int mei_me_read_fws(const struct mei_device *dev, int where, u32 *val)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	return pci_read_config_dword(pdev, where, val);
+}
+
+/**
+ * mei_me_quirk_probe - probe for devices that doesn't valid ME interface
+ *
+ * @pdev: PCI device structure
+ * @cfg: per generation config
+ *
+ * Return: true if ME Interface is valid, false otherwise
+ */
+static bool mei_me_quirk_probe(struct pci_dev *pdev,
+				const struct mei_cfg *cfg)
+{
+	if (cfg->quirk_probe && cfg->quirk_probe(pdev)) {
+		dev_info(&pdev->dev, "Device doesn't have valid ME Interface\n");
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * mei_me_probe - Device Initialization Routine
+ *
+ * @pdev: PCI device structure
+ * @ent: entry in kcs_pci_tbl
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	const struct mei_cfg *cfg;
+	struct mei_device *dev;
+	struct mei_me_hw *hw;
+	unsigned int irqflags;
+	int err;
+
+	cfg = mei_me_get_cfg(ent->driver_data);
+	if (!cfg)
+		return -ENODEV;
+
+	if (!mei_me_quirk_probe(pdev, cfg))
+		return -ENODEV;
+
+	/* enable pci dev */
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable pci device.\n");
+		goto end;
+	}
+	/* set PCI host mastering  */
+	pci_set_master(pdev);
+	/* pci request regions and mapping IO device memory for mei driver */
+	err = pcim_iomap_regions(pdev, BIT(0), KBUILD_MODNAME);
+	if (err) {
+		dev_err(&pdev->dev, "failed to get pci regions.\n");
+		goto end;
+	}
+
+	if (dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)) ||
+	    dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64))) {
+
+		err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
+		if (err)
+			err = dma_set_coherent_mask(&pdev->dev,
+						    DMA_BIT_MASK(32));
+	}
+	if (err) {
+		dev_err(&pdev->dev, "No usable DMA configuration, aborting\n");
+		goto end;
+	}
+
+	/* allocates and initializes the mei dev structure */
+	dev = mei_me_dev_init(&pdev->dev, cfg);
+	if (!dev) {
+		err = -ENOMEM;
+		goto end;
+	}
+	hw = to_me_hw(dev);
+	hw->mem_addr = pcim_iomap_table(pdev)[0];
+	hw->read_fws = mei_me_read_fws;
+
+	pci_enable_msi(pdev);
+
+	hw->irq = pdev->irq;
+
+	 /* request and enable interrupt */
+	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_ONESHOT : IRQF_SHARED;
+
+	err = request_threaded_irq(pdev->irq,
+			mei_me_irq_quick_handler,
+			mei_me_irq_thread_handler,
+			irqflags, KBUILD_MODNAME, dev);
+	if (err) {
+		dev_err(&pdev->dev, "request_threaded_irq failure. irq = %d\n",
+		       pdev->irq);
+		goto end;
+	}
+
+	if (mei_start(dev)) {
+		dev_err(&pdev->dev, "init hw failure.\n");
+		err = -ENODEV;
+		goto release_irq;
+	}
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_ME_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+
+	err = mei_register(dev, &pdev->dev);
+	if (err)
+		goto stop;
+
+	pci_set_drvdata(pdev, dev);
+
+	/*
+	 * MEI requires to resume from runtime suspend mode
+	 * in order to perform link reset flow upon system suspend.
+	 */
+	dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE);
+
+	/*
+	 * ME maps runtime suspend/resume to D0i states,
+	 * hence we need to go around native PCI runtime service which
+	 * eventually brings the device into D3cold/hot state,
+	 * but the mei device cannot wake up from D3 unlike from D0i3.
+	 * To get around the PCI device native runtime pm,
+	 * ME uses runtime pm domain handlers which take precedence
+	 * over the driver's pm handlers.
+	 */
+	mei_me_set_pm_domain(dev);
+
+	if (mei_pg_is_enabled(dev)) {
+		pm_runtime_put_noidle(&pdev->dev);
+		if (hw->d0i3_supported)
+			pm_runtime_allow(&pdev->dev);
+	}
+
+	dev_dbg(&pdev->dev, "initialization successful.\n");
+
+	return 0;
+
+stop:
+	mei_stop(dev);
+release_irq:
+	mei_cancel_work(dev);
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+end:
+	dev_err(&pdev->dev, "initialization failed.\n");
+	return err;
+}
+
+/**
+ * mei_me_shutdown - Device Removal Routine
+ *
+ * @pdev: PCI device structure
+ *
+ * mei_me_shutdown is called from the reboot notifier
+ * it's a simplified version of remove so we go down
+ * faster.
+ */
+static void mei_me_shutdown(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return;
+
+	dev_dbg(&pdev->dev, "shutdown\n");
+	mei_stop(dev);
+
+	mei_me_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+}
+
+/**
+ * mei_me_remove - Device Removal Routine
+ *
+ * @pdev: PCI device structure
+ *
+ * mei_me_remove is called by the PCI subsystem to alert the driver
+ * that it should release a PCI device.
+ */
+static void mei_me_remove(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return;
+
+	if (mei_pg_is_enabled(dev))
+		pm_runtime_get_noresume(&pdev->dev);
+
+	dev_dbg(&pdev->dev, "stop\n");
+	mei_stop(dev);
+
+	mei_me_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+
+	free_irq(pdev->irq, dev);
+
+	mei_deregister(dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mei_me_pci_suspend(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev = pci_get_drvdata(pdev);
+
+	if (!dev)
+		return -ENODEV;
+
+	dev_dbg(&pdev->dev, "suspend\n");
+
+	mei_stop(dev);
+
+	mei_disable_interrupts(dev);
+
+	free_irq(pdev->irq, dev);
+	pci_disable_msi(pdev);
+
+	return 0;
+}
+
+static int mei_me_pci_resume(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	unsigned int irqflags;
+	int err;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	pci_enable_msi(pdev);
+
+	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_ONESHOT : IRQF_SHARED;
+
+	/* request and enable interrupt */
+	err = request_threaded_irq(pdev->irq,
+			mei_me_irq_quick_handler,
+			mei_me_irq_thread_handler,
+			irqflags, KBUILD_MODNAME, dev);
+
+	if (err) {
+		dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
+				pdev->irq);
+		return err;
+	}
+
+	err = mei_restart(dev);
+	if (err)
+		return err;
+
+	/* Start timer if stopped in suspend */
+	schedule_delayed_work(&dev->timer_work, HZ);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int mei_me_pm_runtime_idle(struct device *device)
+{
+	struct mei_device *dev;
+
+	dev_dbg(device, "rpm: me: runtime_idle\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+	if (mei_write_is_idle(dev))
+		pm_runtime_autosuspend(device);
+
+	return -EBUSY;
+}
+
+static int mei_me_pm_runtime_suspend(struct device *device)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(device, "rpm: me: runtime suspend\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (mei_write_is_idle(dev))
+		ret = mei_me_pg_enter_sync(dev);
+	else
+		ret = -EAGAIN;
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(device, "rpm: me: runtime suspend ret=%d\n", ret);
+
+	if (ret && ret != -EAGAIN)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+static int mei_me_pm_runtime_resume(struct device *device)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(device, "rpm: me: runtime resume\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	ret = mei_me_pg_exit_sync(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(device, "rpm: me: runtime resume ret = %d\n", ret);
+
+	if (ret)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+/**
+ * mei_me_set_pm_domain - fill and set pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_me_set_pm_domain(struct mei_device *dev)
+{
+	struct pci_dev *pdev  = to_pci_dev(dev->dev);
+
+	if (pdev->dev.bus && pdev->dev.bus->pm) {
+		dev->pg_domain.ops = *pdev->dev.bus->pm;
+
+		dev->pg_domain.ops.runtime_suspend = mei_me_pm_runtime_suspend;
+		dev->pg_domain.ops.runtime_resume = mei_me_pm_runtime_resume;
+		dev->pg_domain.ops.runtime_idle = mei_me_pm_runtime_idle;
+
+		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
+	}
+}
+
+/**
+ * mei_me_unset_pm_domain - clean pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_me_unset_pm_domain(struct mei_device *dev)
+{
+	/* stop using pm callbacks if any */
+	dev_pm_domain_set(dev->dev, NULL);
+}
+
+static const struct dev_pm_ops mei_me_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mei_me_pci_suspend,
+				mei_me_pci_resume)
+	SET_RUNTIME_PM_OPS(
+		mei_me_pm_runtime_suspend,
+		mei_me_pm_runtime_resume,
+		mei_me_pm_runtime_idle)
+};
+
+#define MEI_ME_PM_OPS	(&mei_me_pm_ops)
+#else
+#define MEI_ME_PM_OPS	NULL
+#endif /* CONFIG_PM */
+/*
+ *  PCI driver structure
+ */
+static struct pci_driver mei_me_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = mei_me_pci_tbl,
+	.probe = mei_me_probe,
+	.remove = mei_me_remove,
+	.shutdown = mei_me_shutdown,
+	.driver.pm = MEI_ME_PM_OPS,
+	.driver.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+};
+
+module_pci_driver(mei_me_driver);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/misc/mei/pci-txe.c b/drivers/misc/mei/pci-txe.c
new file mode 100644
index 000000000..4bf26ce61
--- /dev/null
+++ b/drivers/misc/mei/pci-txe.c
@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2013-2020, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+
+#include "mei_dev.h"
+#include "hw-txe.h"
+
+static const struct pci_device_id mei_txe_pci_tbl[] = {
+	{PCI_VDEVICE(INTEL, 0x0F18)}, /* Baytrail */
+	{PCI_VDEVICE(INTEL, 0x2298)}, /* Cherrytrail */
+
+	{0, }
+};
+MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl);
+
+#ifdef CONFIG_PM
+static inline void mei_txe_set_pm_domain(struct mei_device *dev);
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev);
+#else
+static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev) {}
+#endif /* CONFIG_PM */
+
+/**
+ * mei_txe_probe - Device Initialization Routine
+ *
+ * @pdev: PCI device structure
+ * @ent: entry in mei_txe_pci_tbl
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	struct mei_device *dev;
+	struct mei_txe_hw *hw;
+	const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR);
+	int err;
+
+	/* enable pci dev */
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable pci device.\n");
+		goto end;
+	}
+	/* set PCI host mastering  */
+	pci_set_master(pdev);
+	/* pci request regions and mapping IO device memory for mei driver */
+	err = pcim_iomap_regions(pdev, mask, KBUILD_MODNAME);
+	if (err) {
+		dev_err(&pdev->dev, "failed to get pci regions.\n");
+		goto end;
+	}
+
+	err = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
+	if (err) {
+		err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+		if (err) {
+			dev_err(&pdev->dev, "No suitable DMA available.\n");
+			goto end;
+		}
+	}
+
+	/* allocates and initializes the mei dev structure */
+	dev = mei_txe_dev_init(pdev);
+	if (!dev) {
+		err = -ENOMEM;
+		goto end;
+	}
+	hw = to_txe_hw(dev);
+	hw->mem_addr = pcim_iomap_table(pdev);
+
+	pci_enable_msi(pdev);
+
+	/* clear spurious interrupts */
+	mei_clear_interrupts(dev);
+
+	/* request and enable interrupt  */
+	if (pci_dev_msi_enabled(pdev))
+		err = request_threaded_irq(pdev->irq,
+			NULL,
+			mei_txe_irq_thread_handler,
+			IRQF_ONESHOT, KBUILD_MODNAME, dev);
+	else
+		err = request_threaded_irq(pdev->irq,
+			mei_txe_irq_quick_handler,
+			mei_txe_irq_thread_handler,
+			IRQF_SHARED, KBUILD_MODNAME, dev);
+	if (err) {
+		dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n",
+			pdev->irq);
+		goto end;
+	}
+
+	if (mei_start(dev)) {
+		dev_err(&pdev->dev, "init hw failure.\n");
+		err = -ENODEV;
+		goto release_irq;
+	}
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+
+	err = mei_register(dev, &pdev->dev);
+	if (err)
+		goto stop;
+
+	pci_set_drvdata(pdev, dev);
+
+	/*
+	 * MEI requires to resume from runtime suspend mode
+	 * in order to perform link reset flow upon system suspend.
+	 */
+	dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE);
+
+	/*
+	 * TXE maps runtime suspend/resume to own power gating states,
+	 * hence we need to go around native PCI runtime service which
+	 * eventually brings the device into D3cold/hot state.
+	 * But the TXE device cannot wake up from D3 unlike from own
+	 * power gating. To get around PCI device native runtime pm,
+	 * TXE uses runtime pm domain handlers which take precedence.
+	 */
+	mei_txe_set_pm_domain(dev);
+
+	pm_runtime_put_noidle(&pdev->dev);
+
+	return 0;
+
+stop:
+	mei_stop(dev);
+release_irq:
+	mei_cancel_work(dev);
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+end:
+	dev_err(&pdev->dev, "initialization failed.\n");
+	return err;
+}
+
+/**
+ * mei_txe_remove - Device Shutdown Routine
+ *
+ * @pdev: PCI device structure
+ *
+ *  mei_txe_shutdown is called from the reboot notifier
+ *  it's a simplified version of remove so we go down
+ *  faster.
+ */
+static void mei_txe_shutdown(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return;
+
+	dev_dbg(&pdev->dev, "shutdown\n");
+	mei_stop(dev);
+
+	mei_txe_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+}
+
+/**
+ * mei_txe_remove - Device Removal Routine
+ *
+ * @pdev: PCI device structure
+ *
+ * mei_remove is called by the PCI subsystem to alert the driver
+ * that it should release a PCI device.
+ */
+static void mei_txe_remove(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev) {
+		dev_err(&pdev->dev, "mei: dev == NULL\n");
+		return;
+	}
+
+	pm_runtime_get_noresume(&pdev->dev);
+
+	mei_stop(dev);
+
+	mei_txe_unset_pm_domain(dev);
+
+	mei_disable_interrupts(dev);
+	free_irq(pdev->irq, dev);
+
+	mei_deregister(dev);
+}
+
+
+#ifdef CONFIG_PM_SLEEP
+static int mei_txe_pci_suspend(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev = pci_get_drvdata(pdev);
+
+	if (!dev)
+		return -ENODEV;
+
+	dev_dbg(&pdev->dev, "suspend\n");
+
+	mei_stop(dev);
+
+	mei_disable_interrupts(dev);
+
+	free_irq(pdev->irq, dev);
+	pci_disable_msi(pdev);
+
+	return 0;
+}
+
+static int mei_txe_pci_resume(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int err;
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	pci_enable_msi(pdev);
+
+	mei_clear_interrupts(dev);
+
+	/* request and enable interrupt */
+	if (pci_dev_msi_enabled(pdev))
+		err = request_threaded_irq(pdev->irq,
+			NULL,
+			mei_txe_irq_thread_handler,
+			IRQF_ONESHOT, KBUILD_MODNAME, dev);
+	else
+		err = request_threaded_irq(pdev->irq,
+			mei_txe_irq_quick_handler,
+			mei_txe_irq_thread_handler,
+			IRQF_SHARED, KBUILD_MODNAME, dev);
+	if (err) {
+		dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
+				pdev->irq);
+		return err;
+	}
+
+	err = mei_restart(dev);
+
+	return err;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int mei_txe_pm_runtime_idle(struct device *device)
+{
+	struct mei_device *dev;
+
+	dev_dbg(device, "rpm: txe: runtime_idle\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+	if (mei_write_is_idle(dev))
+		pm_runtime_autosuspend(device);
+
+	return -EBUSY;
+}
+static int mei_txe_pm_runtime_suspend(struct device *device)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(device, "rpm: txe: runtime suspend\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (mei_write_is_idle(dev))
+		ret = mei_txe_aliveness_set_sync(dev, 0);
+	else
+		ret = -EAGAIN;
+
+	/* keep irq on we are staying in D0 */
+
+	dev_dbg(device, "rpm: txe: runtime suspend ret=%d\n", ret);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (ret && ret != -EAGAIN)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+static int mei_txe_pm_runtime_resume(struct device *device)
+{
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(device, "rpm: txe: runtime resume\n");
+
+	dev = dev_get_drvdata(device);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	mei_enable_interrupts(dev);
+
+	ret = mei_txe_aliveness_set_sync(dev, 1);
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(device, "rpm: txe: runtime resume ret = %d\n", ret);
+
+	if (ret)
+		schedule_work(&dev->reset_work);
+
+	return ret;
+}
+
+/**
+ * mei_txe_set_pm_domain - fill and set pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_txe_set_pm_domain(struct mei_device *dev)
+{
+	struct pci_dev *pdev  = to_pci_dev(dev->dev);
+
+	if (pdev->dev.bus && pdev->dev.bus->pm) {
+		dev->pg_domain.ops = *pdev->dev.bus->pm;
+
+		dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
+		dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
+		dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
+
+		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
+	}
+}
+
+/**
+ * mei_txe_unset_pm_domain - clean pm domain structure for device
+ *
+ * @dev: mei_device
+ */
+static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
+{
+	/* stop using pm callbacks if any */
+	dev_pm_domain_set(dev->dev, NULL);
+}
+
+static const struct dev_pm_ops mei_txe_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
+				mei_txe_pci_resume)
+	SET_RUNTIME_PM_OPS(
+		mei_txe_pm_runtime_suspend,
+		mei_txe_pm_runtime_resume,
+		mei_txe_pm_runtime_idle)
+};
+
+#define MEI_TXE_PM_OPS	(&mei_txe_pm_ops)
+#else
+#define MEI_TXE_PM_OPS	NULL
+#endif /* CONFIG_PM */
+
+/*
+ *  PCI driver structure
+ */
+static struct pci_driver mei_txe_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = mei_txe_pci_tbl,
+	.probe = mei_txe_probe,
+	.remove = mei_txe_remove,
+	.shutdown = mei_txe_shutdown,
+	.driver.pm = MEI_TXE_PM_OPS,
+};
+
+module_pci_driver(mei_txe_driver);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
+MODULE_LICENSE("GPL v2");