Adding upstream version 6.1.76.upstream/6.1.76upstream

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

9 files changed, 7055 insertions, 0 deletions

diff --git a/drivers/bus/mhi/host/Kconfig b/drivers/bus/mhi/host/Kconfig
new file mode 100644
index 000000000..da5cd0c9f
--- /dev/null
+++ b/drivers/bus/mhi/host/Kconfig
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# MHI bus
+#
+# Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+#
+
+config MHI_BUS
+	tristate "Modem Host Interface (MHI) bus"
+	help
+	  Bus driver for MHI protocol. Modem Host Interface (MHI) is a
+	  communication protocol used by the host processors to control
+	  and communicate with modem devices over a high speed peripheral
+	  bus or shared memory.
+
+config MHI_BUS_DEBUG
+	bool "Debugfs support for the MHI bus"
+	depends on MHI_BUS && DEBUG_FS
+	help
+	  Enable debugfs support for use with the MHI transport. Allows
+	  reading and/or modifying some values within the MHI controller
+	  for debug and test purposes.
+
+config MHI_BUS_PCI_GENERIC
+	tristate "MHI PCI controller driver"
+	depends on MHI_BUS
+	depends on PCI
+	help
+	  This driver provides MHI PCI controller driver for devices such as
+	  Qualcomm SDX55 based PCIe modems.
+
diff --git a/drivers/bus/mhi/host/Makefile b/drivers/bus/mhi/host/Makefile
new file mode 100644
index 000000000..859c2f384
--- /dev/null
+++ b/drivers/bus/mhi/host/Makefile
@@ -0,0 +1,6 @@
+obj-$(CONFIG_MHI_BUS) += mhi.o
+mhi-y := init.o main.o pm.o boot.o
+mhi-$(CONFIG_MHI_BUS_DEBUG) += debugfs.o
+
+obj-$(CONFIG_MHI_BUS_PCI_GENERIC) += mhi_pci_generic.o
+mhi_pci_generic-y += pci_generic.o
diff --git a/drivers/bus/mhi/host/boot.c b/drivers/bus/mhi/host/boot.c
new file mode 100644
index 000000000..55e909f8c
--- /dev/null
+++ b/drivers/bus/mhi/host/boot.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/firmware.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include "internal.h"
+
+/* Setup RDDM vector table for RDDM transfer and program RXVEC */
+int mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
+		     struct image_info *img_info)
+{
+	struct mhi_buf *mhi_buf = img_info->mhi_buf;
+	struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
+	void __iomem *base = mhi_cntrl->bhie;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 sequence_id;
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < img_info->entries - 1; i++, mhi_buf++, bhi_vec++) {
+		bhi_vec->dma_addr = mhi_buf->dma_addr;
+		bhi_vec->size = mhi_buf->len;
+	}
+
+	dev_dbg(dev, "BHIe programming for RDDM\n");
+
+	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_HIGH_OFFS,
+		      upper_32_bits(mhi_buf->dma_addr));
+
+	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECADDR_LOW_OFFS,
+		      lower_32_bits(mhi_buf->dma_addr));
+
+	mhi_write_reg(mhi_cntrl, base, BHIE_RXVECSIZE_OFFS, mhi_buf->len);
+	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_RXVECSTATUS_SEQNUM_BMSK);
+
+	ret = mhi_write_reg_field(mhi_cntrl, base, BHIE_RXVECDB_OFFS,
+				  BHIE_RXVECDB_SEQNUM_BMSK, sequence_id);
+	if (ret) {
+		dev_err(dev, "Failed to write sequence ID for BHIE_RXVECDB\n");
+		return ret;
+	}
+
+	dev_dbg(dev, "Address: %p and len: 0x%zx sequence: %u\n",
+		&mhi_buf->dma_addr, mhi_buf->len, sequence_id);
+
+	return 0;
+}
+
+/* Collect RDDM buffer during kernel panic */
+static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
+{
+	int ret;
+	u32 rx_status;
+	enum mhi_ee_type ee;
+	const u32 delayus = 2000;
+	u32 retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
+	const u32 rddm_timeout_us = 200000;
+	int rddm_retry = rddm_timeout_us / delayus;
+	void __iomem *base = mhi_cntrl->bhie;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	dev_dbg(dev, "Entered with pm_state:%s dev_state:%s ee:%s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		mhi_state_str(mhi_cntrl->dev_state),
+		TO_MHI_EXEC_STR(mhi_cntrl->ee));
+
+	/*
+	 * This should only be executing during a kernel panic, we expect all
+	 * other cores to shutdown while we're collecting RDDM buffer. After
+	 * returning from this function, we expect the device to reset.
+	 *
+	 * Normaly, we read/write pm_state only after grabbing the
+	 * pm_lock, since we're in a panic, skipping it. Also there is no
+	 * gurantee that this state change would take effect since
+	 * we're setting it w/o grabbing pm_lock
+	 */
+	mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+	/* update should take the effect immediately */
+	smp_wmb();
+
+	/*
+	 * Make sure device is not already in RDDM. In case the device asserts
+	 * and a kernel panic follows, device will already be in RDDM.
+	 * Do not trigger SYS ERR again and proceed with waiting for
+	 * image download completion.
+	 */
+	ee = mhi_get_exec_env(mhi_cntrl);
+	if (ee == MHI_EE_MAX)
+		goto error_exit_rddm;
+
+	if (ee != MHI_EE_RDDM) {
+		dev_dbg(dev, "Trigger device into RDDM mode using SYS ERR\n");
+		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
+
+		dev_dbg(dev, "Waiting for device to enter RDDM\n");
+		while (rddm_retry--) {
+			ee = mhi_get_exec_env(mhi_cntrl);
+			if (ee == MHI_EE_RDDM)
+				break;
+
+			udelay(delayus);
+		}
+
+		if (rddm_retry <= 0) {
+			/* Hardware reset so force device to enter RDDM */
+			dev_dbg(dev,
+				"Did not enter RDDM, do a host req reset\n");
+			mhi_write_reg(mhi_cntrl, mhi_cntrl->regs,
+				      MHI_SOC_RESET_REQ_OFFSET,
+				      MHI_SOC_RESET_REQ);
+			udelay(delayus);
+		}
+
+		ee = mhi_get_exec_env(mhi_cntrl);
+	}
+
+	dev_dbg(dev,
+		"Waiting for RDDM image download via BHIe, current EE:%s\n",
+		TO_MHI_EXEC_STR(ee));
+
+	while (retry--) {
+		ret = mhi_read_reg_field(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS,
+					 BHIE_RXVECSTATUS_STATUS_BMSK, &rx_status);
+		if (ret)
+			return -EIO;
+
+		if (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL)
+			return 0;
+
+		udelay(delayus);
+	}
+
+	ee = mhi_get_exec_env(mhi_cntrl);
+	ret = mhi_read_reg(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS, &rx_status);
+
+	dev_err(dev, "RXVEC_STATUS: 0x%x\n", rx_status);
+
+error_exit_rddm:
+	dev_err(dev, "RDDM transfer failed. Current EE: %s\n",
+		TO_MHI_EXEC_STR(ee));
+
+	return -EIO;
+}
+
+/* Download RDDM image from device */
+int mhi_download_rddm_image(struct mhi_controller *mhi_cntrl, bool in_panic)
+{
+	void __iomem *base = mhi_cntrl->bhie;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 rx_status;
+
+	if (in_panic)
+		return __mhi_download_rddm_in_panic(mhi_cntrl);
+
+	dev_dbg(dev, "Waiting for RDDM image download via BHIe\n");
+
+	/* Wait for the image download to complete */
+	wait_event_timeout(mhi_cntrl->state_event,
+			   mhi_read_reg_field(mhi_cntrl, base,
+					      BHIE_RXVECSTATUS_OFFS,
+					      BHIE_RXVECSTATUS_STATUS_BMSK,
+					      &rx_status) || rx_status,
+			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	return (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL) ? 0 : -EIO;
+}
+EXPORT_SYMBOL_GPL(mhi_download_rddm_image);
+
+static int mhi_fw_load_bhie(struct mhi_controller *mhi_cntrl,
+			    const struct mhi_buf *mhi_buf)
+{
+	void __iomem *base = mhi_cntrl->bhie;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
+	u32 tx_status, sequence_id;
+	int ret;
+
+	read_lock_bh(pm_lock);
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+		read_unlock_bh(pm_lock);
+		return -EIO;
+	}
+
+	sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_TXVECSTATUS_SEQNUM_BMSK);
+	dev_dbg(dev, "Starting image download via BHIe. Sequence ID: %u\n",
+		sequence_id);
+	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_HIGH_OFFS,
+		      upper_32_bits(mhi_buf->dma_addr));
+
+	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_LOW_OFFS,
+		      lower_32_bits(mhi_buf->dma_addr));
+
+	mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len);
+
+	ret = mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS,
+				  BHIE_TXVECDB_SEQNUM_BMSK, sequence_id);
+	read_unlock_bh(pm_lock);
+
+	if (ret)
+		return ret;
+
+	/* Wait for the image download to complete */
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
+				 mhi_read_reg_field(mhi_cntrl, base,
+						   BHIE_TXVECSTATUS_OFFS,
+						   BHIE_TXVECSTATUS_STATUS_BMSK,
+						   &tx_status) || tx_status,
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
+	    tx_status != BHIE_TXVECSTATUS_STATUS_XFER_COMPL)
+		return -EIO;
+
+	return (!ret) ? -ETIMEDOUT : 0;
+}
+
+static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl,
+			   dma_addr_t dma_addr,
+			   size_t size)
+{
+	u32 tx_status, val, session_id;
+	int i, ret;
+	void __iomem *base = mhi_cntrl->bhi;
+	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	struct {
+		char *name;
+		u32 offset;
+	} error_reg[] = {
+		{ "ERROR_CODE", BHI_ERRCODE },
+		{ "ERROR_DBG1", BHI_ERRDBG1 },
+		{ "ERROR_DBG2", BHI_ERRDBG2 },
+		{ "ERROR_DBG3", BHI_ERRDBG3 },
+		{ NULL },
+	};
+
+	read_lock_bh(pm_lock);
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+		read_unlock_bh(pm_lock);
+		goto invalid_pm_state;
+	}
+
+	session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
+	dev_dbg(dev, "Starting image download via BHI. Session ID: %u\n",
+		session_id);
+	mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
+	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
+		      upper_32_bits(dma_addr));
+	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
+		      lower_32_bits(dma_addr));
+	mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
+	mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
+	read_unlock_bh(pm_lock);
+
+	/* Wait for the image download to complete */
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+			   MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state) ||
+			   mhi_read_reg_field(mhi_cntrl, base, BHI_STATUS,
+					      BHI_STATUS_MASK, &tx_status) || tx_status,
+			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+		goto invalid_pm_state;
+
+	if (tx_status == BHI_STATUS_ERROR) {
+		dev_err(dev, "Image transfer failed\n");
+		read_lock_bh(pm_lock);
+		if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+			for (i = 0; error_reg[i].name; i++) {
+				ret = mhi_read_reg(mhi_cntrl, base,
+						   error_reg[i].offset, &val);
+				if (ret)
+					break;
+				dev_err(dev, "Reg: %s value: 0x%x\n",
+					error_reg[i].name, val);
+			}
+		}
+		read_unlock_bh(pm_lock);
+		goto invalid_pm_state;
+	}
+
+	return (!ret) ? -ETIMEDOUT : 0;
+
+invalid_pm_state:
+
+	return -EIO;
+}
+
+void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl,
+			 struct image_info *image_info)
+{
+	int i;
+	struct mhi_buf *mhi_buf = image_info->mhi_buf;
+
+	for (i = 0; i < image_info->entries; i++, mhi_buf++)
+		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
+				  mhi_buf->buf, mhi_buf->dma_addr);
+
+	kfree(image_info->mhi_buf);
+	kfree(image_info);
+}
+
+int mhi_alloc_bhie_table(struct mhi_controller *mhi_cntrl,
+			 struct image_info **image_info,
+			 size_t alloc_size)
+{
+	size_t seg_size = mhi_cntrl->seg_len;
+	int segments = DIV_ROUND_UP(alloc_size, seg_size) + 1;
+	int i;
+	struct image_info *img_info;
+	struct mhi_buf *mhi_buf;
+
+	img_info = kzalloc(sizeof(*img_info), GFP_KERNEL);
+	if (!img_info)
+		return -ENOMEM;
+
+	/* Allocate memory for entries */
+	img_info->mhi_buf = kcalloc(segments, sizeof(*img_info->mhi_buf),
+				    GFP_KERNEL);
+	if (!img_info->mhi_buf)
+		goto error_alloc_mhi_buf;
+
+	/* Allocate and populate vector table */
+	mhi_buf = img_info->mhi_buf;
+	for (i = 0; i < segments; i++, mhi_buf++) {
+		size_t vec_size = seg_size;
+
+		/* Vector table is the last entry */
+		if (i == segments - 1)
+			vec_size = sizeof(struct bhi_vec_entry) * i;
+
+		mhi_buf->len = vec_size;
+		mhi_buf->buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
+						  vec_size, &mhi_buf->dma_addr,
+						  GFP_KERNEL);
+		if (!mhi_buf->buf)
+			goto error_alloc_segment;
+	}
+
+	img_info->bhi_vec = img_info->mhi_buf[segments - 1].buf;
+	img_info->entries = segments;
+	*image_info = img_info;
+
+	return 0;
+
+error_alloc_segment:
+	for (--i, --mhi_buf; i >= 0; i--, mhi_buf--)
+		dma_free_coherent(mhi_cntrl->cntrl_dev, mhi_buf->len,
+				  mhi_buf->buf, mhi_buf->dma_addr);
+
+error_alloc_mhi_buf:
+	kfree(img_info);
+
+	return -ENOMEM;
+}
+
+static void mhi_firmware_copy(struct mhi_controller *mhi_cntrl,
+			      const struct firmware *firmware,
+			      struct image_info *img_info)
+{
+	size_t remainder = firmware->size;
+	size_t to_cpy;
+	const u8 *buf = firmware->data;
+	struct mhi_buf *mhi_buf = img_info->mhi_buf;
+	struct bhi_vec_entry *bhi_vec = img_info->bhi_vec;
+
+	while (remainder) {
+		to_cpy = min(remainder, mhi_buf->len);
+		memcpy(mhi_buf->buf, buf, to_cpy);
+		bhi_vec->dma_addr = mhi_buf->dma_addr;
+		bhi_vec->size = to_cpy;
+
+		buf += to_cpy;
+		remainder -= to_cpy;
+		bhi_vec++;
+		mhi_buf++;
+	}
+}
+
+void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
+{
+	const struct firmware *firmware = NULL;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_pm_state new_state;
+	const char *fw_name;
+	void *buf;
+	dma_addr_t dma_addr;
+	size_t size;
+	int i, ret;
+
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		dev_err(dev, "Device MHI is not in valid state\n");
+		return;
+	}
+
+	/* save hardware info from BHI */
+	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_SERIALNU,
+			   &mhi_cntrl->serial_number);
+	if (ret)
+		dev_err(dev, "Could not capture serial number via BHI\n");
+
+	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++) {
+		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_OEMPKHASH(i),
+				   &mhi_cntrl->oem_pk_hash[i]);
+		if (ret) {
+			dev_err(dev, "Could not capture OEM PK HASH via BHI\n");
+			break;
+		}
+	}
+
+	/* wait for ready on pass through or any other execution environment */
+	if (!MHI_FW_LOAD_CAPABLE(mhi_cntrl->ee))
+		goto fw_load_ready_state;
+
+	fw_name = (mhi_cntrl->ee == MHI_EE_EDL) ?
+		mhi_cntrl->edl_image : mhi_cntrl->fw_image;
+
+	if (!fw_name || (mhi_cntrl->fbc_download && (!mhi_cntrl->sbl_size ||
+						     !mhi_cntrl->seg_len))) {
+		dev_err(dev,
+			"No firmware image defined or !sbl_size || !seg_len\n");
+		goto error_fw_load;
+	}
+
+	ret = request_firmware(&firmware, fw_name, dev);
+	if (ret) {
+		dev_err(dev, "Error loading firmware: %d\n", ret);
+		goto error_fw_load;
+	}
+
+	size = (mhi_cntrl->fbc_download) ? mhi_cntrl->sbl_size : firmware->size;
+
+	/* SBL size provided is maximum size, not necessarily the image size */
+	if (size > firmware->size)
+		size = firmware->size;
+
+	buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev, size, &dma_addr,
+				 GFP_KERNEL);
+	if (!buf) {
+		release_firmware(firmware);
+		goto error_fw_load;
+	}
+
+	/* Download image using BHI */
+	memcpy(buf, firmware->data, size);
+	ret = mhi_fw_load_bhi(mhi_cntrl, dma_addr, size);
+	dma_free_coherent(mhi_cntrl->cntrl_dev, size, buf, dma_addr);
+
+	/* Error or in EDL mode, we're done */
+	if (ret) {
+		dev_err(dev, "MHI did not load image over BHI, ret: %d\n", ret);
+		release_firmware(firmware);
+		goto error_fw_load;
+	}
+
+	/* Wait for ready since EDL image was loaded */
+	if (fw_name == mhi_cntrl->edl_image) {
+		release_firmware(firmware);
+		goto fw_load_ready_state;
+	}
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	mhi_cntrl->dev_state = MHI_STATE_RESET;
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	/*
+	 * If we're doing fbc, populate vector tables while
+	 * device transitioning into MHI READY state
+	 */
+	if (mhi_cntrl->fbc_download) {
+		ret = mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->fbc_image,
+					   firmware->size);
+		if (ret) {
+			release_firmware(firmware);
+			goto error_fw_load;
+		}
+
+		/* Load the firmware into BHIE vec table */
+		mhi_firmware_copy(mhi_cntrl, firmware, mhi_cntrl->fbc_image);
+	}
+
+	release_firmware(firmware);
+
+fw_load_ready_state:
+	/* Transitioning into MHI RESET->READY state */
+	ret = mhi_ready_state_transition(mhi_cntrl);
+	if (ret) {
+		dev_err(dev, "MHI did not enter READY state\n");
+		goto error_ready_state;
+	}
+
+	dev_info(dev, "Wait for device to enter SBL or Mission mode\n");
+	return;
+
+error_ready_state:
+	if (mhi_cntrl->fbc_download) {
+		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
+		mhi_cntrl->fbc_image = NULL;
+	}
+
+error_fw_load:
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_FW_DL_ERR);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	if (new_state == MHI_PM_FW_DL_ERR)
+		wake_up_all(&mhi_cntrl->state_event);
+}
+
+int mhi_download_amss_image(struct mhi_controller *mhi_cntrl)
+{
+	struct image_info *image_info = mhi_cntrl->fbc_image;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_pm_state new_state;
+	int ret;
+
+	if (!image_info)
+		return -EIO;
+
+	ret = mhi_fw_load_bhie(mhi_cntrl,
+			       /* Vector table is the last entry */
+			       &image_info->mhi_buf[image_info->entries - 1]);
+	if (ret) {
+		dev_err(dev, "MHI did not load AMSS, ret:%d\n", ret);
+		write_lock_irq(&mhi_cntrl->pm_lock);
+		new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_FW_DL_ERR);
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		if (new_state == MHI_PM_FW_DL_ERR)
+			wake_up_all(&mhi_cntrl->state_event);
+	}
+
+	return ret;
+}
diff --git a/drivers/bus/mhi/host/debugfs.c b/drivers/bus/mhi/host/debugfs.c
new file mode 100644
index 000000000..cfec7811d
--- /dev/null
+++ b/drivers/bus/mhi/host/debugfs.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include "internal.h"
+
+static int mhi_debugfs_states_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+
+	/* states */
+	seq_printf(m, "PM state: %s Device: %s MHI state: %s EE: %s wake: %s\n",
+		   to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		   mhi_is_active(mhi_cntrl) ? "Active" : "Inactive",
+		   mhi_state_str(mhi_cntrl->dev_state),
+		   TO_MHI_EXEC_STR(mhi_cntrl->ee),
+		   mhi_cntrl->wake_set ? "true" : "false");
+
+	/* counters */
+	seq_printf(m, "M0: %u M2: %u M3: %u", mhi_cntrl->M0, mhi_cntrl->M2,
+		   mhi_cntrl->M3);
+
+	seq_printf(m, " device wake: %u pending packets: %u\n",
+		   atomic_read(&mhi_cntrl->dev_wake),
+		   atomic_read(&mhi_cntrl->pending_pkts));
+
+	return 0;
+}
+
+static int mhi_debugfs_events_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+	struct mhi_event *mhi_event;
+	struct mhi_event_ctxt *er_ctxt;
+	int i;
+
+	if (!mhi_is_active(mhi_cntrl)) {
+		seq_puts(m, "Device not ready\n");
+		return -ENODEV;
+	}
+
+	er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings;
+						i++, er_ctxt++, mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		if (mhi_event->offload_ev) {
+			seq_printf(m, "Index: %d is an offload event ring\n",
+				   i);
+			continue;
+		}
+
+		seq_printf(m, "Index: %d intmod count: %lu time: %lu",
+			   i, (le32_to_cpu(er_ctxt->intmod) & EV_CTX_INTMODC_MASK) >>
+			   __ffs(EV_CTX_INTMODC_MASK),
+			   (le32_to_cpu(er_ctxt->intmod) & EV_CTX_INTMODT_MASK) >>
+			   __ffs(EV_CTX_INTMODT_MASK));
+
+		seq_printf(m, " base: 0x%0llx len: 0x%llx", le64_to_cpu(er_ctxt->rbase),
+			   le64_to_cpu(er_ctxt->rlen));
+
+		seq_printf(m, " rp: 0x%llx wp: 0x%llx", le64_to_cpu(er_ctxt->rp),
+			   le64_to_cpu(er_ctxt->wp));
+
+		seq_printf(m, " local rp: 0x%pK db: 0x%pad\n", ring->rp,
+			   &mhi_event->db_cfg.db_val);
+	}
+
+	return 0;
+}
+
+static int mhi_debugfs_channels_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+	struct mhi_chan *mhi_chan;
+	struct mhi_chan_ctxt *chan_ctxt;
+	int i;
+
+	if (!mhi_is_active(mhi_cntrl)) {
+		seq_puts(m, "Device not ready\n");
+		return -ENODEV;
+	}
+
+	mhi_chan = mhi_cntrl->mhi_chan;
+	chan_ctxt = mhi_cntrl->mhi_ctxt->chan_ctxt;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, chan_ctxt++, mhi_chan++) {
+		struct mhi_ring *ring = &mhi_chan->tre_ring;
+
+		if (mhi_chan->offload_ch) {
+			seq_printf(m, "%s(%u) is an offload channel\n",
+				   mhi_chan->name, mhi_chan->chan);
+			continue;
+		}
+
+		if (!mhi_chan->mhi_dev)
+			continue;
+
+		seq_printf(m,
+			   "%s(%u) state: 0x%lx brstmode: 0x%lx pollcfg: 0x%lx",
+			   mhi_chan->name, mhi_chan->chan, (le32_to_cpu(chan_ctxt->chcfg) &
+			   CHAN_CTX_CHSTATE_MASK) >> __ffs(CHAN_CTX_CHSTATE_MASK),
+			   (le32_to_cpu(chan_ctxt->chcfg) & CHAN_CTX_BRSTMODE_MASK) >>
+			   __ffs(CHAN_CTX_BRSTMODE_MASK), (le32_to_cpu(chan_ctxt->chcfg) &
+			   CHAN_CTX_POLLCFG_MASK) >> __ffs(CHAN_CTX_POLLCFG_MASK));
+
+		seq_printf(m, " type: 0x%x event ring: %u", le32_to_cpu(chan_ctxt->chtype),
+			   le32_to_cpu(chan_ctxt->erindex));
+
+		seq_printf(m, " base: 0x%llx len: 0x%llx rp: 0x%llx wp: 0x%llx",
+			   le64_to_cpu(chan_ctxt->rbase), le64_to_cpu(chan_ctxt->rlen),
+			   le64_to_cpu(chan_ctxt->rp), le64_to_cpu(chan_ctxt->wp));
+
+		seq_printf(m, " local rp: 0x%pK local wp: 0x%pK db: 0x%pad\n",
+			   ring->rp, ring->wp,
+			   &mhi_chan->db_cfg.db_val);
+	}
+
+	return 0;
+}
+
+static int mhi_device_info_show(struct device *dev, void *data)
+{
+	struct mhi_device *mhi_dev;
+
+	if (dev->bus != &mhi_bus_type)
+		return 0;
+
+	mhi_dev = to_mhi_device(dev);
+
+	seq_printf((struct seq_file *)data, "%s: type: %s dev_wake: %u",
+		   mhi_dev->name, mhi_dev->dev_type ? "Controller" : "Transfer",
+		   mhi_dev->dev_wake);
+
+	/* for transfer device types only */
+	if (mhi_dev->dev_type == MHI_DEVICE_XFER)
+		seq_printf((struct seq_file *)data, " channels: %u(UL)/%u(DL)",
+			   mhi_dev->ul_chan_id, mhi_dev->dl_chan_id);
+
+	seq_puts((struct seq_file *)data, "\n");
+
+	return 0;
+}
+
+static int mhi_debugfs_devices_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+
+	if (!mhi_is_active(mhi_cntrl)) {
+		seq_puts(m, "Device not ready\n");
+		return -ENODEV;
+	}
+
+	/* Show controller and client(s) info */
+	mhi_device_info_show(&mhi_cntrl->mhi_dev->dev, m);
+	device_for_each_child(&mhi_cntrl->mhi_dev->dev, m, mhi_device_info_show);
+
+	return 0;
+}
+
+static int mhi_debugfs_regdump_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+	enum mhi_state state;
+	enum mhi_ee_type ee;
+	int i, ret = -EIO;
+	u32 val;
+	void __iomem *mhi_base = mhi_cntrl->regs;
+	void __iomem *bhi_base = mhi_cntrl->bhi;
+	void __iomem *bhie_base = mhi_cntrl->bhie;
+	void __iomem *wake_db = mhi_cntrl->wake_db;
+	struct {
+		const char *name;
+		int offset;
+		void __iomem *base;
+	} regs[] = {
+		{ "MHI_REGLEN", MHIREGLEN, mhi_base},
+		{ "MHI_VER", MHIVER, mhi_base},
+		{ "MHI_CFG", MHICFG, mhi_base},
+		{ "MHI_CTRL", MHICTRL, mhi_base},
+		{ "MHI_STATUS", MHISTATUS, mhi_base},
+		{ "MHI_WAKE_DB", 0, wake_db},
+		{ "BHI_EXECENV", BHI_EXECENV, bhi_base},
+		{ "BHI_STATUS", BHI_STATUS, bhi_base},
+		{ "BHI_ERRCODE", BHI_ERRCODE, bhi_base},
+		{ "BHI_ERRDBG1", BHI_ERRDBG1, bhi_base},
+		{ "BHI_ERRDBG2", BHI_ERRDBG2, bhi_base},
+		{ "BHI_ERRDBG3", BHI_ERRDBG3, bhi_base},
+		{ "BHIE_TXVEC_DB", BHIE_TXVECDB_OFFS, bhie_base},
+		{ "BHIE_TXVEC_STATUS", BHIE_TXVECSTATUS_OFFS, bhie_base},
+		{ "BHIE_RXVEC_DB", BHIE_RXVECDB_OFFS, bhie_base},
+		{ "BHIE_RXVEC_STATUS", BHIE_RXVECSTATUS_OFFS, bhie_base},
+		{ NULL },
+	};
+
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+		return ret;
+
+	seq_printf(m, "Host PM state: %s Device state: %s EE: %s\n",
+		   to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		   mhi_state_str(mhi_cntrl->dev_state),
+		   TO_MHI_EXEC_STR(mhi_cntrl->ee));
+
+	state = mhi_get_mhi_state(mhi_cntrl);
+	ee = mhi_get_exec_env(mhi_cntrl);
+	seq_printf(m, "Device EE: %s state: %s\n", TO_MHI_EXEC_STR(ee),
+		   mhi_state_str(state));
+
+	for (i = 0; regs[i].name; i++) {
+		if (!regs[i].base)
+			continue;
+		ret = mhi_read_reg(mhi_cntrl, regs[i].base, regs[i].offset,
+				   &val);
+		if (ret)
+			continue;
+
+		seq_printf(m, "%s: 0x%x\n", regs[i].name, val);
+	}
+
+	return 0;
+}
+
+static int mhi_debugfs_device_wake_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+	struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
+
+	if (!mhi_is_active(mhi_cntrl)) {
+		seq_puts(m, "Device not ready\n");
+		return -ENODEV;
+	}
+
+	seq_printf(m,
+		   "Wake count: %d\n%s\n", mhi_dev->dev_wake,
+		   "Usage: echo get/put > device_wake to vote/unvote for M0");
+
+	return 0;
+}
+
+static ssize_t mhi_debugfs_device_wake_write(struct file *file,
+					     const char __user *ubuf,
+					     size_t count, loff_t *ppos)
+{
+	struct seq_file	*m = file->private_data;
+	struct mhi_controller *mhi_cntrl = m->private;
+	struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
+	char buf[16];
+	int ret = -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+		return -EFAULT;
+
+	if (!strncmp(buf, "get", 3)) {
+		ret = mhi_device_get_sync(mhi_dev);
+	} else if (!strncmp(buf, "put", 3)) {
+		mhi_device_put(mhi_dev);
+		ret = 0;
+	}
+
+	return ret ? ret : count;
+}
+
+static int mhi_debugfs_timeout_ms_show(struct seq_file *m, void *d)
+{
+	struct mhi_controller *mhi_cntrl = m->private;
+
+	seq_printf(m, "%u ms\n", mhi_cntrl->timeout_ms);
+
+	return 0;
+}
+
+static ssize_t mhi_debugfs_timeout_ms_write(struct file *file,
+					    const char __user *ubuf,
+					    size_t count, loff_t *ppos)
+{
+	struct seq_file	*m = file->private_data;
+	struct mhi_controller *mhi_cntrl = m->private;
+	u32 timeout_ms;
+
+	if (kstrtou32_from_user(ubuf, count, 0, &timeout_ms))
+		return -EINVAL;
+
+	mhi_cntrl->timeout_ms = timeout_ms;
+
+	return count;
+}
+
+static int mhi_debugfs_states_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_states_show, inode->i_private);
+}
+
+static int mhi_debugfs_events_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_events_show, inode->i_private);
+}
+
+static int mhi_debugfs_channels_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_channels_show, inode->i_private);
+}
+
+static int mhi_debugfs_devices_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_devices_show, inode->i_private);
+}
+
+static int mhi_debugfs_regdump_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_regdump_show, inode->i_private);
+}
+
+static int mhi_debugfs_device_wake_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_device_wake_show, inode->i_private);
+}
+
+static int mhi_debugfs_timeout_ms_open(struct inode *inode, struct file *fp)
+{
+	return single_open(fp, mhi_debugfs_timeout_ms_show, inode->i_private);
+}
+
+static const struct file_operations debugfs_states_fops = {
+	.open = mhi_debugfs_states_open,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_events_fops = {
+	.open = mhi_debugfs_events_open,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_channels_fops = {
+	.open = mhi_debugfs_channels_open,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_devices_fops = {
+	.open = mhi_debugfs_devices_open,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_regdump_fops = {
+	.open = mhi_debugfs_regdump_open,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_device_wake_fops = {
+	.open = mhi_debugfs_device_wake_open,
+	.write = mhi_debugfs_device_wake_write,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static const struct file_operations debugfs_timeout_ms_fops = {
+	.open = mhi_debugfs_timeout_ms_open,
+	.write = mhi_debugfs_timeout_ms_write,
+	.release = single_release,
+	.read = seq_read,
+};
+
+static struct dentry *mhi_debugfs_root;
+
+void mhi_create_debugfs(struct mhi_controller *mhi_cntrl)
+{
+	mhi_cntrl->debugfs_dentry =
+			debugfs_create_dir(dev_name(&mhi_cntrl->mhi_dev->dev),
+					   mhi_debugfs_root);
+
+	debugfs_create_file("states", 0444, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_states_fops);
+	debugfs_create_file("events", 0444, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_events_fops);
+	debugfs_create_file("channels", 0444, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_channels_fops);
+	debugfs_create_file("devices", 0444, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_devices_fops);
+	debugfs_create_file("regdump", 0444, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_regdump_fops);
+	debugfs_create_file("device_wake", 0644, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_device_wake_fops);
+	debugfs_create_file("timeout_ms", 0644, mhi_cntrl->debugfs_dentry,
+			    mhi_cntrl, &debugfs_timeout_ms_fops);
+}
+
+void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl)
+{
+	debugfs_remove_recursive(mhi_cntrl->debugfs_dentry);
+	mhi_cntrl->debugfs_dentry = NULL;
+}
+
+void mhi_debugfs_init(void)
+{
+	mhi_debugfs_root = debugfs_create_dir(mhi_bus_type.name, NULL);
+}
+
+void mhi_debugfs_exit(void)
+{
+	debugfs_remove_recursive(mhi_debugfs_root);
+}
diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
new file mode 100644
index 000000000..04fbccff6
--- /dev/null
+++ b/drivers/bus/mhi/host/init.c
@@ -0,0 +1,1464 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/bitfield.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include "internal.h"
+
+static DEFINE_IDA(mhi_controller_ida);
+
+const char * const mhi_ee_str[MHI_EE_MAX] = {
+	[MHI_EE_PBL] = "PRIMARY BOOTLOADER",
+	[MHI_EE_SBL] = "SECONDARY BOOTLOADER",
+	[MHI_EE_AMSS] = "MISSION MODE",
+	[MHI_EE_RDDM] = "RAMDUMP DOWNLOAD MODE",
+	[MHI_EE_WFW] = "WLAN FIRMWARE",
+	[MHI_EE_PTHRU] = "PASS THROUGH",
+	[MHI_EE_EDL] = "EMERGENCY DOWNLOAD",
+	[MHI_EE_FP] = "FLASH PROGRAMMER",
+	[MHI_EE_DISABLE_TRANSITION] = "DISABLE",
+	[MHI_EE_NOT_SUPPORTED] = "NOT SUPPORTED",
+};
+
+const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
+	[DEV_ST_TRANSITION_PBL] = "PBL",
+	[DEV_ST_TRANSITION_READY] = "READY",
+	[DEV_ST_TRANSITION_SBL] = "SBL",
+	[DEV_ST_TRANSITION_MISSION_MODE] = "MISSION MODE",
+	[DEV_ST_TRANSITION_FP] = "FLASH PROGRAMMER",
+	[DEV_ST_TRANSITION_SYS_ERR] = "SYS ERROR",
+	[DEV_ST_TRANSITION_DISABLE] = "DISABLE",
+};
+
+const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX] = {
+	[MHI_CH_STATE_TYPE_RESET] = "RESET",
+	[MHI_CH_STATE_TYPE_STOP] = "STOP",
+	[MHI_CH_STATE_TYPE_START] = "START",
+};
+
+static const char * const mhi_pm_state_str[] = {
+	[MHI_PM_STATE_DISABLE] = "DISABLE",
+	[MHI_PM_STATE_POR] = "POWER ON RESET",
+	[MHI_PM_STATE_M0] = "M0",
+	[MHI_PM_STATE_M2] = "M2",
+	[MHI_PM_STATE_M3_ENTER] = "M?->M3",
+	[MHI_PM_STATE_M3] = "M3",
+	[MHI_PM_STATE_M3_EXIT] = "M3->M0",
+	[MHI_PM_STATE_FW_DL_ERR] = "Firmware Download Error",
+	[MHI_PM_STATE_SYS_ERR_DETECT] = "SYS ERROR Detect",
+	[MHI_PM_STATE_SYS_ERR_PROCESS] = "SYS ERROR Process",
+	[MHI_PM_STATE_SHUTDOWN_PROCESS] = "SHUTDOWN Process",
+	[MHI_PM_STATE_LD_ERR_FATAL_DETECT] = "Linkdown or Error Fatal Detect",
+};
+
+const char *to_mhi_pm_state_str(u32 state)
+{
+	int index;
+
+	if (state)
+		index = __fls(state);
+
+	if (!state || index >= ARRAY_SIZE(mhi_pm_state_str))
+		return "Invalid State";
+
+	return mhi_pm_state_str[index];
+}
+
+static ssize_t serial_number_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+	return sysfs_emit(buf, "Serial Number: %u\n",
+			mhi_cntrl->serial_number);
+}
+static DEVICE_ATTR_RO(serial_number);
+
+static ssize_t oem_pk_hash_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	int i, cnt = 0;
+
+	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++)
+		cnt += sysfs_emit_at(buf, cnt, "OEMPKHASH[%d]: 0x%x\n",
+				i, mhi_cntrl->oem_pk_hash[i]);
+
+	return cnt;
+}
+static DEVICE_ATTR_RO(oem_pk_hash);
+
+static ssize_t soc_reset_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf,
+			       size_t count)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+	mhi_soc_reset(mhi_cntrl);
+	return count;
+}
+static DEVICE_ATTR_WO(soc_reset);
+
+static struct attribute *mhi_dev_attrs[] = {
+	&dev_attr_serial_number.attr,
+	&dev_attr_oem_pk_hash.attr,
+	&dev_attr_soc_reset.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(mhi_dev);
+
+/* MHI protocol requires the transfer ring to be aligned with ring length */
+static int mhi_alloc_aligned_ring(struct mhi_controller *mhi_cntrl,
+				  struct mhi_ring *ring,
+				  u64 len)
+{
+	ring->alloc_size = len + (len - 1);
+	ring->pre_aligned = dma_alloc_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
+					       &ring->dma_handle, GFP_KERNEL);
+	if (!ring->pre_aligned)
+		return -ENOMEM;
+
+	ring->iommu_base = (ring->dma_handle + (len - 1)) & ~(len - 1);
+	ring->base = ring->pre_aligned + (ring->iommu_base - ring->dma_handle);
+
+	return 0;
+}
+
+void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl)
+{
+	int i;
+	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
+	}
+
+	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
+}
+
+int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	unsigned long irq_flags = IRQF_SHARED | IRQF_NO_SUSPEND;
+	int i, ret;
+
+	/* if controller driver has set irq_flags, use it */
+	if (mhi_cntrl->irq_flags)
+		irq_flags = mhi_cntrl->irq_flags;
+
+	/* Setup BHI_INTVEC IRQ */
+	ret = request_threaded_irq(mhi_cntrl->irq[0], mhi_intvec_handler,
+				   mhi_intvec_threaded_handler,
+				   irq_flags,
+				   "bhi", mhi_cntrl);
+	if (ret)
+		return ret;
+	/*
+	 * IRQs should be enabled during mhi_async_power_up(), so disable them explicitly here.
+	 * Due to the use of IRQF_SHARED flag as default while requesting IRQs, we assume that
+	 * IRQ_NOAUTOEN is not applicable.
+	 */
+	disable_irq(mhi_cntrl->irq[0]);
+
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		if (mhi_event->irq >= mhi_cntrl->nr_irqs) {
+			dev_err(dev, "irq %d not available for event ring\n",
+				mhi_event->irq);
+			ret = -EINVAL;
+			goto error_request;
+		}
+
+		ret = request_irq(mhi_cntrl->irq[mhi_event->irq],
+				  mhi_irq_handler,
+				  irq_flags,
+				  "mhi", mhi_event);
+		if (ret) {
+			dev_err(dev, "Error requesting irq:%d for ev:%d\n",
+				mhi_cntrl->irq[mhi_event->irq], i);
+			goto error_request;
+		}
+
+		disable_irq(mhi_cntrl->irq[mhi_event->irq]);
+	}
+
+	return 0;
+
+error_request:
+	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
+	}
+	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
+
+	return ret;
+}
+
+void mhi_deinit_dev_ctxt(struct mhi_controller *mhi_cntrl)
+{
+	int i;
+	struct mhi_ctxt *mhi_ctxt = mhi_cntrl->mhi_ctxt;
+	struct mhi_cmd *mhi_cmd;
+	struct mhi_event *mhi_event;
+	struct mhi_ring *ring;
+
+	mhi_cmd = mhi_cntrl->mhi_cmd;
+	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++) {
+		ring = &mhi_cmd->ring;
+		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
+				  ring->pre_aligned, ring->dma_handle);
+		ring->base = NULL;
+		ring->iommu_base = 0;
+	}
+
+	dma_free_coherent(mhi_cntrl->cntrl_dev,
+			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
+			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
+
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		ring = &mhi_event->ring;
+		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
+				  ring->pre_aligned, ring->dma_handle);
+		ring->base = NULL;
+		ring->iommu_base = 0;
+	}
+
+	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
+			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
+			  mhi_ctxt->er_ctxt_addr);
+
+	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
+			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
+			  mhi_ctxt->chan_ctxt_addr);
+
+	kfree(mhi_ctxt);
+	mhi_cntrl->mhi_ctxt = NULL;
+}
+
+int mhi_init_dev_ctxt(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_ctxt *mhi_ctxt;
+	struct mhi_chan_ctxt *chan_ctxt;
+	struct mhi_event_ctxt *er_ctxt;
+	struct mhi_cmd_ctxt *cmd_ctxt;
+	struct mhi_chan *mhi_chan;
+	struct mhi_event *mhi_event;
+	struct mhi_cmd *mhi_cmd;
+	u32 tmp;
+	int ret = -ENOMEM, i;
+
+	atomic_set(&mhi_cntrl->dev_wake, 0);
+	atomic_set(&mhi_cntrl->pending_pkts, 0);
+
+	mhi_ctxt = kzalloc(sizeof(*mhi_ctxt), GFP_KERNEL);
+	if (!mhi_ctxt)
+		return -ENOMEM;
+
+	/* Setup channel ctxt */
+	mhi_ctxt->chan_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
+						 sizeof(*mhi_ctxt->chan_ctxt) *
+						 mhi_cntrl->max_chan,
+						 &mhi_ctxt->chan_ctxt_addr,
+						 GFP_KERNEL);
+	if (!mhi_ctxt->chan_ctxt)
+		goto error_alloc_chan_ctxt;
+
+	mhi_chan = mhi_cntrl->mhi_chan;
+	chan_ctxt = mhi_ctxt->chan_ctxt;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, chan_ctxt++, mhi_chan++) {
+		/* Skip if it is an offload channel */
+		if (mhi_chan->offload_ch)
+			continue;
+
+		tmp = le32_to_cpu(chan_ctxt->chcfg);
+		tmp &= ~CHAN_CTX_CHSTATE_MASK;
+		tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED);
+		tmp &= ~CHAN_CTX_BRSTMODE_MASK;
+		tmp |= FIELD_PREP(CHAN_CTX_BRSTMODE_MASK, mhi_chan->db_cfg.brstmode);
+		tmp &= ~CHAN_CTX_POLLCFG_MASK;
+		tmp |= FIELD_PREP(CHAN_CTX_POLLCFG_MASK, mhi_chan->db_cfg.pollcfg);
+		chan_ctxt->chcfg = cpu_to_le32(tmp);
+
+		chan_ctxt->chtype = cpu_to_le32(mhi_chan->type);
+		chan_ctxt->erindex = cpu_to_le32(mhi_chan->er_index);
+
+		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
+		mhi_chan->tre_ring.db_addr = (void __iomem *)&chan_ctxt->wp;
+	}
+
+	/* Setup event context */
+	mhi_ctxt->er_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
+					       sizeof(*mhi_ctxt->er_ctxt) *
+					       mhi_cntrl->total_ev_rings,
+					       &mhi_ctxt->er_ctxt_addr,
+					       GFP_KERNEL);
+	if (!mhi_ctxt->er_ctxt)
+		goto error_alloc_er_ctxt;
+
+	er_ctxt = mhi_ctxt->er_ctxt;
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
+		     mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		/* Skip if it is an offload event */
+		if (mhi_event->offload_ev)
+			continue;
+
+		tmp = le32_to_cpu(er_ctxt->intmod);
+		tmp &= ~EV_CTX_INTMODC_MASK;
+		tmp &= ~EV_CTX_INTMODT_MASK;
+		tmp |= FIELD_PREP(EV_CTX_INTMODT_MASK, mhi_event->intmod);
+		er_ctxt->intmod = cpu_to_le32(tmp);
+
+		er_ctxt->ertype = cpu_to_le32(MHI_ER_TYPE_VALID);
+		er_ctxt->msivec = cpu_to_le32(mhi_event->irq);
+		mhi_event->db_cfg.db_mode = true;
+
+		ring->el_size = sizeof(struct mhi_ring_element);
+		ring->len = ring->el_size * ring->elements;
+		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
+		if (ret)
+			goto error_alloc_er;
+
+		/*
+		 * If the read pointer equals to the write pointer, then the
+		 * ring is empty
+		 */
+		ring->rp = ring->wp = ring->base;
+		er_ctxt->rbase = cpu_to_le64(ring->iommu_base);
+		er_ctxt->rp = er_ctxt->wp = er_ctxt->rbase;
+		er_ctxt->rlen = cpu_to_le64(ring->len);
+		ring->ctxt_wp = &er_ctxt->wp;
+	}
+
+	/* Setup cmd context */
+	ret = -ENOMEM;
+	mhi_ctxt->cmd_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
+						sizeof(*mhi_ctxt->cmd_ctxt) *
+						NR_OF_CMD_RINGS,
+						&mhi_ctxt->cmd_ctxt_addr,
+						GFP_KERNEL);
+	if (!mhi_ctxt->cmd_ctxt)
+		goto error_alloc_er;
+
+	mhi_cmd = mhi_cntrl->mhi_cmd;
+	cmd_ctxt = mhi_ctxt->cmd_ctxt;
+	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
+		struct mhi_ring *ring = &mhi_cmd->ring;
+
+		ring->el_size = sizeof(struct mhi_ring_element);
+		ring->elements = CMD_EL_PER_RING;
+		ring->len = ring->el_size * ring->elements;
+		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
+		if (ret)
+			goto error_alloc_cmd;
+
+		ring->rp = ring->wp = ring->base;
+		cmd_ctxt->rbase = cpu_to_le64(ring->iommu_base);
+		cmd_ctxt->rp = cmd_ctxt->wp = cmd_ctxt->rbase;
+		cmd_ctxt->rlen = cpu_to_le64(ring->len);
+		ring->ctxt_wp = &cmd_ctxt->wp;
+	}
+
+	mhi_cntrl->mhi_ctxt = mhi_ctxt;
+
+	return 0;
+
+error_alloc_cmd:
+	for (--i, --mhi_cmd; i >= 0; i--, mhi_cmd--) {
+		struct mhi_ring *ring = &mhi_cmd->ring;
+
+		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
+				  ring->pre_aligned, ring->dma_handle);
+	}
+	dma_free_coherent(mhi_cntrl->cntrl_dev,
+			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
+			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
+	i = mhi_cntrl->total_ev_rings;
+	mhi_event = mhi_cntrl->mhi_event + i;
+
+error_alloc_er:
+	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		if (mhi_event->offload_ev)
+			continue;
+
+		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
+				  ring->pre_aligned, ring->dma_handle);
+	}
+	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
+			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
+			  mhi_ctxt->er_ctxt_addr);
+
+error_alloc_er_ctxt:
+	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
+			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
+			  mhi_ctxt->chan_ctxt_addr);
+
+error_alloc_chan_ctxt:
+	kfree(mhi_ctxt);
+
+	return ret;
+}
+
+int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
+{
+	u32 val;
+	int i, ret;
+	struct mhi_chan *mhi_chan;
+	struct mhi_event *mhi_event;
+	void __iomem *base = mhi_cntrl->regs;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	struct {
+		u32 offset;
+		u32 val;
+	} reg_info[] = {
+		{
+			CCABAP_HIGHER,
+			upper_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
+		},
+		{
+			CCABAP_LOWER,
+			lower_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
+		},
+		{
+			ECABAP_HIGHER,
+			upper_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
+		},
+		{
+			ECABAP_LOWER,
+			lower_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
+		},
+		{
+			CRCBAP_HIGHER,
+			upper_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
+		},
+		{
+			CRCBAP_LOWER,
+			lower_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
+		},
+		{
+			MHICTRLBASE_HIGHER,
+			upper_32_bits(mhi_cntrl->iova_start),
+		},
+		{
+			MHICTRLBASE_LOWER,
+			lower_32_bits(mhi_cntrl->iova_start),
+		},
+		{
+			MHIDATABASE_HIGHER,
+			upper_32_bits(mhi_cntrl->iova_start),
+		},
+		{
+			MHIDATABASE_LOWER,
+			lower_32_bits(mhi_cntrl->iova_start),
+		},
+		{
+			MHICTRLLIMIT_HIGHER,
+			upper_32_bits(mhi_cntrl->iova_stop),
+		},
+		{
+			MHICTRLLIMIT_LOWER,
+			lower_32_bits(mhi_cntrl->iova_stop),
+		},
+		{
+			MHIDATALIMIT_HIGHER,
+			upper_32_bits(mhi_cntrl->iova_stop),
+		},
+		{
+			MHIDATALIMIT_LOWER,
+			lower_32_bits(mhi_cntrl->iova_stop),
+		},
+		{0, 0}
+	};
+
+	dev_dbg(dev, "Initializing MHI registers\n");
+
+	/* Read channel db offset */
+	ret = mhi_read_reg(mhi_cntrl, base, CHDBOFF, &val);
+	if (ret) {
+		dev_err(dev, "Unable to read CHDBOFF register\n");
+		return -EIO;
+	}
+
+	if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
+		dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
+			val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
+		return -ERANGE;
+	}
+
+	/* Setup wake db */
+	mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
+	mhi_cntrl->wake_set = false;
+
+	/* Setup channel db address for each channel in tre_ring */
+	mhi_chan = mhi_cntrl->mhi_chan;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, val += 8, mhi_chan++)
+		mhi_chan->tre_ring.db_addr = base + val;
+
+	/* Read event ring db offset */
+	ret = mhi_read_reg(mhi_cntrl, base, ERDBOFF, &val);
+	if (ret) {
+		dev_err(dev, "Unable to read ERDBOFF register\n");
+		return -EIO;
+	}
+
+	if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
+		dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
+			val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
+		return -ERANGE;
+	}
+
+	/* Setup event db address for each ev_ring */
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		mhi_event->ring.db_addr = base + val;
+	}
+
+	/* Setup DB register for primary CMD rings */
+	mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING].ring.db_addr = base + CRDB_LOWER;
+
+	/* Write to MMIO registers */
+	for (i = 0; reg_info[i].offset; i++)
+		mhi_write_reg(mhi_cntrl, base, reg_info[i].offset,
+			      reg_info[i].val);
+
+	ret = mhi_write_reg_field(mhi_cntrl, base, MHICFG, MHICFG_NER_MASK,
+				  mhi_cntrl->total_ev_rings);
+	if (ret) {
+		dev_err(dev, "Unable to write MHICFG register\n");
+		return ret;
+	}
+
+	ret = mhi_write_reg_field(mhi_cntrl, base, MHICFG, MHICFG_NHWER_MASK,
+				  mhi_cntrl->hw_ev_rings);
+	if (ret) {
+		dev_err(dev, "Unable to write MHICFG register\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
+			  struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *buf_ring;
+	struct mhi_ring *tre_ring;
+	struct mhi_chan_ctxt *chan_ctxt;
+	u32 tmp;
+
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
+
+	if (!chan_ctxt->rbase) /* Already uninitialized */
+		return;
+
+	dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
+			  tre_ring->pre_aligned, tre_ring->dma_handle);
+	vfree(buf_ring->base);
+
+	buf_ring->base = tre_ring->base = NULL;
+	tre_ring->ctxt_wp = NULL;
+	chan_ctxt->rbase = 0;
+	chan_ctxt->rlen = 0;
+	chan_ctxt->rp = 0;
+	chan_ctxt->wp = 0;
+
+	tmp = le32_to_cpu(chan_ctxt->chcfg);
+	tmp &= ~CHAN_CTX_CHSTATE_MASK;
+	tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED);
+	chan_ctxt->chcfg = cpu_to_le32(tmp);
+
+	/* Update to all cores */
+	smp_wmb();
+}
+
+int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
+		       struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *buf_ring;
+	struct mhi_ring *tre_ring;
+	struct mhi_chan_ctxt *chan_ctxt;
+	u32 tmp;
+	int ret;
+
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+	tre_ring->el_size = sizeof(struct mhi_ring_element);
+	tre_ring->len = tre_ring->el_size * tre_ring->elements;
+	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
+	ret = mhi_alloc_aligned_ring(mhi_cntrl, tre_ring, tre_ring->len);
+	if (ret)
+		return -ENOMEM;
+
+	buf_ring->el_size = sizeof(struct mhi_buf_info);
+	buf_ring->len = buf_ring->el_size * buf_ring->elements;
+	buf_ring->base = vzalloc(buf_ring->len);
+
+	if (!buf_ring->base) {
+		dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
+				  tre_ring->pre_aligned, tre_ring->dma_handle);
+		return -ENOMEM;
+	}
+
+	tmp = le32_to_cpu(chan_ctxt->chcfg);
+	tmp &= ~CHAN_CTX_CHSTATE_MASK;
+	tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_ENABLED);
+	chan_ctxt->chcfg = cpu_to_le32(tmp);
+
+	chan_ctxt->rbase = cpu_to_le64(tre_ring->iommu_base);
+	chan_ctxt->rp = chan_ctxt->wp = chan_ctxt->rbase;
+	chan_ctxt->rlen = cpu_to_le64(tre_ring->len);
+	tre_ring->ctxt_wp = &chan_ctxt->wp;
+
+	tre_ring->rp = tre_ring->wp = tre_ring->base;
+	buf_ring->rp = buf_ring->wp = buf_ring->base;
+	mhi_chan->db_cfg.db_mode = 1;
+
+	/* Update to all cores */
+	smp_wmb();
+
+	return 0;
+}
+
+static int parse_ev_cfg(struct mhi_controller *mhi_cntrl,
+			const struct mhi_controller_config *config)
+{
+	struct mhi_event *mhi_event;
+	const struct mhi_event_config *event_cfg;
+	struct device *dev = mhi_cntrl->cntrl_dev;
+	int i, num;
+
+	num = config->num_events;
+	mhi_cntrl->total_ev_rings = num;
+	mhi_cntrl->mhi_event = kcalloc(num, sizeof(*mhi_cntrl->mhi_event),
+				       GFP_KERNEL);
+	if (!mhi_cntrl->mhi_event)
+		return -ENOMEM;
+
+	/* Populate event ring */
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < num; i++) {
+		event_cfg = &config->event_cfg[i];
+
+		mhi_event->er_index = i;
+		mhi_event->ring.elements = event_cfg->num_elements;
+		mhi_event->intmod = event_cfg->irq_moderation_ms;
+		mhi_event->irq = event_cfg->irq;
+
+		if (event_cfg->channel != U32_MAX) {
+			/* This event ring has a dedicated channel */
+			mhi_event->chan = event_cfg->channel;
+			if (mhi_event->chan >= mhi_cntrl->max_chan) {
+				dev_err(dev,
+					"Event Ring channel not available\n");
+				goto error_ev_cfg;
+			}
+
+			mhi_event->mhi_chan =
+				&mhi_cntrl->mhi_chan[mhi_event->chan];
+		}
+
+		/* Priority is fixed to 1 for now */
+		mhi_event->priority = 1;
+
+		mhi_event->db_cfg.brstmode = event_cfg->mode;
+		if (MHI_INVALID_BRSTMODE(mhi_event->db_cfg.brstmode))
+			goto error_ev_cfg;
+
+		if (mhi_event->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
+			mhi_event->db_cfg.process_db = mhi_db_brstmode;
+		else
+			mhi_event->db_cfg.process_db = mhi_db_brstmode_disable;
+
+		mhi_event->data_type = event_cfg->data_type;
+
+		switch (mhi_event->data_type) {
+		case MHI_ER_DATA:
+			mhi_event->process_event = mhi_process_data_event_ring;
+			break;
+		case MHI_ER_CTRL:
+			mhi_event->process_event = mhi_process_ctrl_ev_ring;
+			break;
+		default:
+			dev_err(dev, "Event Ring type not supported\n");
+			goto error_ev_cfg;
+		}
+
+		mhi_event->hw_ring = event_cfg->hardware_event;
+		if (mhi_event->hw_ring)
+			mhi_cntrl->hw_ev_rings++;
+		else
+			mhi_cntrl->sw_ev_rings++;
+
+		mhi_event->cl_manage = event_cfg->client_managed;
+		mhi_event->offload_ev = event_cfg->offload_channel;
+		mhi_event++;
+	}
+
+	return 0;
+
+error_ev_cfg:
+
+	kfree(mhi_cntrl->mhi_event);
+	return -EINVAL;
+}
+
+static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
+			const struct mhi_controller_config *config)
+{
+	const struct mhi_channel_config *ch_cfg;
+	struct device *dev = mhi_cntrl->cntrl_dev;
+	int i;
+	u32 chan;
+
+	mhi_cntrl->max_chan = config->max_channels;
+
+	/*
+	 * The allocation of MHI channels can exceed 32KB in some scenarios,
+	 * so to avoid any memory possible allocation failures, vzalloc is
+	 * used here
+	 */
+	mhi_cntrl->mhi_chan = vzalloc(mhi_cntrl->max_chan *
+				      sizeof(*mhi_cntrl->mhi_chan));
+	if (!mhi_cntrl->mhi_chan)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&mhi_cntrl->lpm_chans);
+
+	/* Populate channel configurations */
+	for (i = 0; i < config->num_channels; i++) {
+		struct mhi_chan *mhi_chan;
+
+		ch_cfg = &config->ch_cfg[i];
+
+		chan = ch_cfg->num;
+		if (chan >= mhi_cntrl->max_chan) {
+			dev_err(dev, "Channel %d not available\n", chan);
+			goto error_chan_cfg;
+		}
+
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		mhi_chan->name = ch_cfg->name;
+		mhi_chan->chan = chan;
+
+		mhi_chan->tre_ring.elements = ch_cfg->num_elements;
+		if (!mhi_chan->tre_ring.elements)
+			goto error_chan_cfg;
+
+		/*
+		 * For some channels, local ring length should be bigger than
+		 * the transfer ring length due to internal logical channels
+		 * in device. So host can queue much more buffers than transfer
+		 * ring length. Example, RSC channels should have a larger local
+		 * channel length than transfer ring length.
+		 */
+		mhi_chan->buf_ring.elements = ch_cfg->local_elements;
+		if (!mhi_chan->buf_ring.elements)
+			mhi_chan->buf_ring.elements = mhi_chan->tre_ring.elements;
+		mhi_chan->er_index = ch_cfg->event_ring;
+		mhi_chan->dir = ch_cfg->dir;
+
+		/*
+		 * For most channels, chtype is identical to channel directions.
+		 * So, if it is not defined then assign channel direction to
+		 * chtype
+		 */
+		mhi_chan->type = ch_cfg->type;
+		if (!mhi_chan->type)
+			mhi_chan->type = (enum mhi_ch_type)mhi_chan->dir;
+
+		mhi_chan->ee_mask = ch_cfg->ee_mask;
+		mhi_chan->db_cfg.pollcfg = ch_cfg->pollcfg;
+		mhi_chan->lpm_notify = ch_cfg->lpm_notify;
+		mhi_chan->offload_ch = ch_cfg->offload_channel;
+		mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
+		mhi_chan->pre_alloc = ch_cfg->auto_queue;
+		mhi_chan->wake_capable = ch_cfg->wake_capable;
+
+		/*
+		 * If MHI host allocates buffers, then the channel direction
+		 * should be DMA_FROM_DEVICE
+		 */
+		if (mhi_chan->pre_alloc && mhi_chan->dir != DMA_FROM_DEVICE) {
+			dev_err(dev, "Invalid channel configuration\n");
+			goto error_chan_cfg;
+		}
+
+		/*
+		 * Bi-directional and direction less channel must be an
+		 * offload channel
+		 */
+		if ((mhi_chan->dir == DMA_BIDIRECTIONAL ||
+		     mhi_chan->dir == DMA_NONE) && !mhi_chan->offload_ch) {
+			dev_err(dev, "Invalid channel configuration\n");
+			goto error_chan_cfg;
+		}
+
+		if (!mhi_chan->offload_ch) {
+			mhi_chan->db_cfg.brstmode = ch_cfg->doorbell;
+			if (MHI_INVALID_BRSTMODE(mhi_chan->db_cfg.brstmode)) {
+				dev_err(dev, "Invalid Door bell mode\n");
+				goto error_chan_cfg;
+			}
+		}
+
+		if (mhi_chan->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
+			mhi_chan->db_cfg.process_db = mhi_db_brstmode;
+		else
+			mhi_chan->db_cfg.process_db = mhi_db_brstmode_disable;
+
+		mhi_chan->configured = true;
+
+		if (mhi_chan->lpm_notify)
+			list_add_tail(&mhi_chan->node, &mhi_cntrl->lpm_chans);
+	}
+
+	return 0;
+
+error_chan_cfg:
+	vfree(mhi_cntrl->mhi_chan);
+
+	return -EINVAL;
+}
+
+static int parse_config(struct mhi_controller *mhi_cntrl,
+			const struct mhi_controller_config *config)
+{
+	int ret;
+
+	/* Parse MHI channel configuration */
+	ret = parse_ch_cfg(mhi_cntrl, config);
+	if (ret)
+		return ret;
+
+	/* Parse MHI event configuration */
+	ret = parse_ev_cfg(mhi_cntrl, config);
+	if (ret)
+		goto error_ev_cfg;
+
+	mhi_cntrl->timeout_ms = config->timeout_ms;
+	if (!mhi_cntrl->timeout_ms)
+		mhi_cntrl->timeout_ms = MHI_TIMEOUT_MS;
+
+	mhi_cntrl->bounce_buf = config->use_bounce_buf;
+	mhi_cntrl->buffer_len = config->buf_len;
+	if (!mhi_cntrl->buffer_len)
+		mhi_cntrl->buffer_len = MHI_MAX_MTU;
+
+	/* By default, host is allowed to ring DB in both M0 and M2 states */
+	mhi_cntrl->db_access = MHI_PM_M0 | MHI_PM_M2;
+	if (config->m2_no_db)
+		mhi_cntrl->db_access &= ~MHI_PM_M2;
+
+	return 0;
+
+error_ev_cfg:
+	vfree(mhi_cntrl->mhi_chan);
+
+	return ret;
+}
+
+int mhi_register_controller(struct mhi_controller *mhi_cntrl,
+			    const struct mhi_controller_config *config)
+{
+	struct mhi_event *mhi_event;
+	struct mhi_chan *mhi_chan;
+	struct mhi_cmd *mhi_cmd;
+	struct mhi_device *mhi_dev;
+	u32 soc_info;
+	int ret, i;
+
+	if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->regs ||
+	    !mhi_cntrl->runtime_get || !mhi_cntrl->runtime_put ||
+	    !mhi_cntrl->status_cb || !mhi_cntrl->read_reg ||
+	    !mhi_cntrl->write_reg || !mhi_cntrl->nr_irqs ||
+	    !mhi_cntrl->irq || !mhi_cntrl->reg_len)
+		return -EINVAL;
+
+	ret = parse_config(mhi_cntrl, config);
+	if (ret)
+		return -EINVAL;
+
+	mhi_cntrl->mhi_cmd = kcalloc(NR_OF_CMD_RINGS,
+				     sizeof(*mhi_cntrl->mhi_cmd), GFP_KERNEL);
+	if (!mhi_cntrl->mhi_cmd) {
+		ret = -ENOMEM;
+		goto err_free_event;
+	}
+
+	INIT_LIST_HEAD(&mhi_cntrl->transition_list);
+	mutex_init(&mhi_cntrl->pm_mutex);
+	rwlock_init(&mhi_cntrl->pm_lock);
+	spin_lock_init(&mhi_cntrl->transition_lock);
+	spin_lock_init(&mhi_cntrl->wlock);
+	INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
+	init_waitqueue_head(&mhi_cntrl->state_event);
+
+	mhi_cntrl->hiprio_wq = alloc_ordered_workqueue("mhi_hiprio_wq", WQ_HIGHPRI);
+	if (!mhi_cntrl->hiprio_wq) {
+		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate workqueue\n");
+		ret = -ENOMEM;
+		goto err_free_cmd;
+	}
+
+	mhi_cmd = mhi_cntrl->mhi_cmd;
+	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++)
+		spin_lock_init(&mhi_cmd->lock);
+
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		/* Skip for offload events */
+		if (mhi_event->offload_ev)
+			continue;
+
+		mhi_event->mhi_cntrl = mhi_cntrl;
+		spin_lock_init(&mhi_event->lock);
+		if (mhi_event->data_type == MHI_ER_CTRL)
+			tasklet_init(&mhi_event->task, mhi_ctrl_ev_task,
+				     (ulong)mhi_event);
+		else
+			tasklet_init(&mhi_event->task, mhi_ev_task,
+				     (ulong)mhi_event);
+	}
+
+	mhi_chan = mhi_cntrl->mhi_chan;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
+		mutex_init(&mhi_chan->mutex);
+		init_completion(&mhi_chan->completion);
+		rwlock_init(&mhi_chan->lock);
+
+		/* used in setting bei field of TRE */
+		mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index];
+		mhi_chan->intmod = mhi_event->intmod;
+	}
+
+	if (mhi_cntrl->bounce_buf) {
+		mhi_cntrl->map_single = mhi_map_single_use_bb;
+		mhi_cntrl->unmap_single = mhi_unmap_single_use_bb;
+	} else {
+		mhi_cntrl->map_single = mhi_map_single_no_bb;
+		mhi_cntrl->unmap_single = mhi_unmap_single_no_bb;
+	}
+
+	/* Read the MHI device info */
+	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs,
+			   SOC_HW_VERSION_OFFS, &soc_info);
+	if (ret)
+		goto err_destroy_wq;
+
+	mhi_cntrl->family_number = FIELD_GET(SOC_HW_VERSION_FAM_NUM_BMSK, soc_info);
+	mhi_cntrl->device_number = FIELD_GET(SOC_HW_VERSION_DEV_NUM_BMSK, soc_info);
+	mhi_cntrl->major_version = FIELD_GET(SOC_HW_VERSION_MAJOR_VER_BMSK, soc_info);
+	mhi_cntrl->minor_version = FIELD_GET(SOC_HW_VERSION_MINOR_VER_BMSK, soc_info);
+
+	mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL);
+	if (mhi_cntrl->index < 0) {
+		ret = mhi_cntrl->index;
+		goto err_destroy_wq;
+	}
+
+	ret = mhi_init_irq_setup(mhi_cntrl);
+	if (ret)
+		goto err_ida_free;
+
+	/* Register controller with MHI bus */
+	mhi_dev = mhi_alloc_device(mhi_cntrl);
+	if (IS_ERR(mhi_dev)) {
+		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate MHI device\n");
+		ret = PTR_ERR(mhi_dev);
+		goto error_setup_irq;
+	}
+
+	mhi_dev->dev_type = MHI_DEVICE_CONTROLLER;
+	mhi_dev->mhi_cntrl = mhi_cntrl;
+	dev_set_name(&mhi_dev->dev, "mhi%d", mhi_cntrl->index);
+	mhi_dev->name = dev_name(&mhi_dev->dev);
+
+	/* Init wakeup source */
+	device_init_wakeup(&mhi_dev->dev, true);
+
+	ret = device_add(&mhi_dev->dev);
+	if (ret)
+		goto err_release_dev;
+
+	mhi_cntrl->mhi_dev = mhi_dev;
+
+	mhi_create_debugfs(mhi_cntrl);
+
+	return 0;
+
+err_release_dev:
+	put_device(&mhi_dev->dev);
+error_setup_irq:
+	mhi_deinit_free_irq(mhi_cntrl);
+err_ida_free:
+	ida_free(&mhi_controller_ida, mhi_cntrl->index);
+err_destroy_wq:
+	destroy_workqueue(mhi_cntrl->hiprio_wq);
+err_free_cmd:
+	kfree(mhi_cntrl->mhi_cmd);
+err_free_event:
+	kfree(mhi_cntrl->mhi_event);
+	vfree(mhi_cntrl->mhi_chan);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_register_controller);
+
+void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
+	struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan;
+	unsigned int i;
+
+	mhi_deinit_free_irq(mhi_cntrl);
+	mhi_destroy_debugfs(mhi_cntrl);
+
+	destroy_workqueue(mhi_cntrl->hiprio_wq);
+	kfree(mhi_cntrl->mhi_cmd);
+	kfree(mhi_cntrl->mhi_event);
+
+	/* Drop the references to MHI devices created for channels */
+	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
+		if (!mhi_chan->mhi_dev)
+			continue;
+
+		put_device(&mhi_chan->mhi_dev->dev);
+	}
+	vfree(mhi_cntrl->mhi_chan);
+
+	device_del(&mhi_dev->dev);
+	put_device(&mhi_dev->dev);
+
+	ida_free(&mhi_controller_ida, mhi_cntrl->index);
+}
+EXPORT_SYMBOL_GPL(mhi_unregister_controller);
+
+struct mhi_controller *mhi_alloc_controller(void)
+{
+	struct mhi_controller *mhi_cntrl;
+
+	mhi_cntrl = kzalloc(sizeof(*mhi_cntrl), GFP_KERNEL);
+
+	return mhi_cntrl;
+}
+EXPORT_SYMBOL_GPL(mhi_alloc_controller);
+
+void mhi_free_controller(struct mhi_controller *mhi_cntrl)
+{
+	kfree(mhi_cntrl);
+}
+EXPORT_SYMBOL_GPL(mhi_free_controller);
+
+int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
+{
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 bhi_off, bhie_off;
+	int ret;
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+
+	ret = mhi_init_dev_ctxt(mhi_cntrl);
+	if (ret)
+		goto error_dev_ctxt;
+
+	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIOFF, &bhi_off);
+	if (ret) {
+		dev_err(dev, "Error getting BHI offset\n");
+		goto error_reg_offset;
+	}
+
+	if (bhi_off >= mhi_cntrl->reg_len) {
+		dev_err(dev, "BHI offset: 0x%x is out of range: 0x%zx\n",
+			bhi_off, mhi_cntrl->reg_len);
+		ret = -EINVAL;
+		goto error_reg_offset;
+	}
+	mhi_cntrl->bhi = mhi_cntrl->regs + bhi_off;
+
+	if (mhi_cntrl->fbc_download || mhi_cntrl->rddm_size) {
+		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIEOFF,
+				   &bhie_off);
+		if (ret) {
+			dev_err(dev, "Error getting BHIE offset\n");
+			goto error_reg_offset;
+		}
+
+		if (bhie_off >= mhi_cntrl->reg_len) {
+			dev_err(dev,
+				"BHIe offset: 0x%x is out of range: 0x%zx\n",
+				bhie_off, mhi_cntrl->reg_len);
+			ret = -EINVAL;
+			goto error_reg_offset;
+		}
+		mhi_cntrl->bhie = mhi_cntrl->regs + bhie_off;
+	}
+
+	if (mhi_cntrl->rddm_size) {
+		/*
+		 * This controller supports RDDM, so we need to manually clear
+		 * BHIE RX registers since POR values are undefined.
+		 */
+		memset_io(mhi_cntrl->bhie + BHIE_RXVECADDR_LOW_OFFS,
+			  0, BHIE_RXVECSTATUS_OFFS - BHIE_RXVECADDR_LOW_OFFS +
+			  4);
+		/*
+		 * Allocate RDDM table for debugging purpose if specified
+		 */
+		mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
+				     mhi_cntrl->rddm_size);
+		if (mhi_cntrl->rddm_image) {
+			ret = mhi_rddm_prepare(mhi_cntrl,
+					       mhi_cntrl->rddm_image);
+			if (ret) {
+				mhi_free_bhie_table(mhi_cntrl,
+						    mhi_cntrl->rddm_image);
+				goto error_reg_offset;
+			}
+		}
+	}
+
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+
+	return 0;
+
+error_reg_offset:
+	mhi_deinit_dev_ctxt(mhi_cntrl);
+
+error_dev_ctxt:
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_prepare_for_power_up);
+
+void mhi_unprepare_after_power_down(struct mhi_controller *mhi_cntrl)
+{
+	if (mhi_cntrl->fbc_image) {
+		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
+		mhi_cntrl->fbc_image = NULL;
+	}
+
+	if (mhi_cntrl->rddm_image) {
+		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->rddm_image);
+		mhi_cntrl->rddm_image = NULL;
+	}
+
+	mhi_cntrl->bhi = NULL;
+	mhi_cntrl->bhie = NULL;
+
+	mhi_deinit_dev_ctxt(mhi_cntrl);
+}
+EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
+
+static void mhi_release_device(struct device *dev)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+
+	/*
+	 * We need to set the mhi_chan->mhi_dev to NULL here since the MHI
+	 * devices for the channels will only get created if the mhi_dev
+	 * associated with it is NULL. This scenario will happen during the
+	 * controller suspend and resume.
+	 */
+	if (mhi_dev->ul_chan)
+		mhi_dev->ul_chan->mhi_dev = NULL;
+
+	if (mhi_dev->dl_chan)
+		mhi_dev->dl_chan->mhi_dev = NULL;
+
+	kfree(mhi_dev);
+}
+
+struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_device *mhi_dev;
+	struct device *dev;
+
+	mhi_dev = kzalloc(sizeof(*mhi_dev), GFP_KERNEL);
+	if (!mhi_dev)
+		return ERR_PTR(-ENOMEM);
+
+	dev = &mhi_dev->dev;
+	device_initialize(dev);
+	dev->bus = &mhi_bus_type;
+	dev->release = mhi_release_device;
+
+	if (mhi_cntrl->mhi_dev) {
+		/* for MHI client devices, parent is the MHI controller device */
+		dev->parent = &mhi_cntrl->mhi_dev->dev;
+	} else {
+		/* for MHI controller device, parent is the bus device (e.g. pci device) */
+		dev->parent = mhi_cntrl->cntrl_dev;
+	}
+
+	mhi_dev->mhi_cntrl = mhi_cntrl;
+	mhi_dev->dev_wake = 0;
+
+	return mhi_dev;
+}
+
+static int mhi_driver_probe(struct device *dev)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct device_driver *drv = dev->driver;
+	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
+	struct mhi_event *mhi_event;
+	struct mhi_chan *ul_chan = mhi_dev->ul_chan;
+	struct mhi_chan *dl_chan = mhi_dev->dl_chan;
+	int ret;
+
+	/* Bring device out of LPM */
+	ret = mhi_device_get_sync(mhi_dev);
+	if (ret)
+		return ret;
+
+	ret = -EINVAL;
+
+	if (ul_chan) {
+		/*
+		 * If channel supports LPM notifications then status_cb should
+		 * be provided
+		 */
+		if (ul_chan->lpm_notify && !mhi_drv->status_cb)
+			goto exit_probe;
+
+		/* For non-offload channels then xfer_cb should be provided */
+		if (!ul_chan->offload_ch && !mhi_drv->ul_xfer_cb)
+			goto exit_probe;
+
+		ul_chan->xfer_cb = mhi_drv->ul_xfer_cb;
+	}
+
+	ret = -EINVAL;
+	if (dl_chan) {
+		/*
+		 * If channel supports LPM notifications then status_cb should
+		 * be provided
+		 */
+		if (dl_chan->lpm_notify && !mhi_drv->status_cb)
+			goto exit_probe;
+
+		/* For non-offload channels then xfer_cb should be provided */
+		if (!dl_chan->offload_ch && !mhi_drv->dl_xfer_cb)
+			goto exit_probe;
+
+		mhi_event = &mhi_cntrl->mhi_event[dl_chan->er_index];
+
+		/*
+		 * If the channel event ring is managed by client, then
+		 * status_cb must be provided so that the framework can
+		 * notify pending data
+		 */
+		if (mhi_event->cl_manage && !mhi_drv->status_cb)
+			goto exit_probe;
+
+		dl_chan->xfer_cb = mhi_drv->dl_xfer_cb;
+	}
+
+	/* Call the user provided probe function */
+	ret = mhi_drv->probe(mhi_dev, mhi_dev->id);
+	if (ret)
+		goto exit_probe;
+
+	mhi_device_put(mhi_dev);
+
+	return ret;
+
+exit_probe:
+	mhi_unprepare_from_transfer(mhi_dev);
+
+	mhi_device_put(mhi_dev);
+
+	return ret;
+}
+
+static int mhi_driver_remove(struct device *dev)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_driver *mhi_drv = to_mhi_driver(dev->driver);
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan;
+	enum mhi_ch_state ch_state[] = {
+		MHI_CH_STATE_DISABLED,
+		MHI_CH_STATE_DISABLED
+	};
+	int dir;
+
+	/* Skip if it is a controller device */
+	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
+		return 0;
+
+	/* Reset both channels */
+	for (dir = 0; dir < 2; dir++) {
+		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
+
+		if (!mhi_chan)
+			continue;
+
+		/* Wake all threads waiting for completion */
+		write_lock_irq(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_EV_CC_INVALID;
+		complete_all(&mhi_chan->completion);
+		write_unlock_irq(&mhi_chan->lock);
+
+		/* Set the channel state to disabled */
+		mutex_lock(&mhi_chan->mutex);
+		write_lock_irq(&mhi_chan->lock);
+		ch_state[dir] = mhi_chan->ch_state;
+		mhi_chan->ch_state = MHI_CH_STATE_SUSPENDED;
+		write_unlock_irq(&mhi_chan->lock);
+
+		/* Reset the non-offload channel */
+		if (!mhi_chan->offload_ch)
+			mhi_reset_chan(mhi_cntrl, mhi_chan);
+
+		mutex_unlock(&mhi_chan->mutex);
+	}
+
+	mhi_drv->remove(mhi_dev);
+
+	/* De-init channel if it was enabled */
+	for (dir = 0; dir < 2; dir++) {
+		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
+
+		if (!mhi_chan)
+			continue;
+
+		mutex_lock(&mhi_chan->mutex);
+
+		if ((ch_state[dir] == MHI_CH_STATE_ENABLED ||
+		     ch_state[dir] == MHI_CH_STATE_STOP) &&
+		    !mhi_chan->offload_ch)
+			mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
+
+		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
+
+		mutex_unlock(&mhi_chan->mutex);
+	}
+
+	while (mhi_dev->dev_wake)
+		mhi_device_put(mhi_dev);
+
+	return 0;
+}
+
+int __mhi_driver_register(struct mhi_driver *mhi_drv, struct module *owner)
+{
+	struct device_driver *driver = &mhi_drv->driver;
+
+	if (!mhi_drv->probe || !mhi_drv->remove)
+		return -EINVAL;
+
+	driver->bus = &mhi_bus_type;
+	driver->owner = owner;
+	driver->probe = mhi_driver_probe;
+	driver->remove = mhi_driver_remove;
+
+	return driver_register(driver);
+}
+EXPORT_SYMBOL_GPL(__mhi_driver_register);
+
+void mhi_driver_unregister(struct mhi_driver *mhi_drv)
+{
+	driver_unregister(&mhi_drv->driver);
+}
+EXPORT_SYMBOL_GPL(mhi_driver_unregister);
+
+static int mhi_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+
+	return add_uevent_var(env, "MODALIAS=" MHI_DEVICE_MODALIAS_FMT,
+					mhi_dev->name);
+}
+
+static int mhi_match(struct device *dev, struct device_driver *drv)
+{
+	struct mhi_device *mhi_dev = to_mhi_device(dev);
+	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
+	const struct mhi_device_id *id;
+
+	/*
+	 * If the device is a controller type then there is no client driver
+	 * associated with it
+	 */
+	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
+		return 0;
+
+	for (id = mhi_drv->id_table; id->chan[0]; id++)
+		if (!strcmp(mhi_dev->name, id->chan)) {
+			mhi_dev->id = id;
+			return 1;
+		}
+
+	return 0;
+};
+
+struct bus_type mhi_bus_type = {
+	.name = "mhi",
+	.dev_name = "mhi",
+	.match = mhi_match,
+	.uevent = mhi_uevent,
+	.dev_groups = mhi_dev_groups,
+};
+
+static int __init mhi_init(void)
+{
+	mhi_debugfs_init();
+	return bus_register(&mhi_bus_type);
+}
+
+static void __exit mhi_exit(void)
+{
+	mhi_debugfs_exit();
+	bus_unregister(&mhi_bus_type);
+}
+
+postcore_initcall(mhi_init);
+module_exit(mhi_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MHI Host Interface");
diff --git a/drivers/bus/mhi/host/internal.h b/drivers/bus/mhi/host/internal.h
new file mode 100644
index 000000000..01fd10a39
--- /dev/null
+++ b/drivers/bus/mhi/host/internal.h
@@ -0,0 +1,383 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#ifndef _MHI_INT_H
+#define _MHI_INT_H
+
+#include "../common.h"
+
+extern struct bus_type mhi_bus_type;
+
+/* Host request register */
+#define MHI_SOC_RESET_REQ_OFFSET			0xb0
+#define MHI_SOC_RESET_REQ				BIT(0)
+
+#define SOC_HW_VERSION_OFFS				0x224
+#define SOC_HW_VERSION_FAM_NUM_BMSK			GENMASK(31, 28)
+#define SOC_HW_VERSION_DEV_NUM_BMSK			GENMASK(27, 16)
+#define SOC_HW_VERSION_MAJOR_VER_BMSK			GENMASK(15, 8)
+#define SOC_HW_VERSION_MINOR_VER_BMSK			GENMASK(7, 0)
+
+struct mhi_ctxt {
+	struct mhi_event_ctxt *er_ctxt;
+	struct mhi_chan_ctxt *chan_ctxt;
+	struct mhi_cmd_ctxt *cmd_ctxt;
+	dma_addr_t er_ctxt_addr;
+	dma_addr_t chan_ctxt_addr;
+	dma_addr_t cmd_ctxt_addr;
+};
+
+struct bhi_vec_entry {
+	u64 dma_addr;
+	u64 size;
+};
+
+enum mhi_ch_state_type {
+	MHI_CH_STATE_TYPE_RESET,
+	MHI_CH_STATE_TYPE_STOP,
+	MHI_CH_STATE_TYPE_START,
+	MHI_CH_STATE_TYPE_MAX,
+};
+
+extern const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX];
+#define TO_CH_STATE_TYPE_STR(state) (((state) >= MHI_CH_STATE_TYPE_MAX) ? \
+				     "INVALID_STATE" : \
+				     mhi_ch_state_type_str[(state)])
+
+#define MHI_INVALID_BRSTMODE(mode) (mode != MHI_DB_BRST_DISABLE && \
+				    mode != MHI_DB_BRST_ENABLE)
+
+extern const char * const mhi_ee_str[MHI_EE_MAX];
+#define TO_MHI_EXEC_STR(ee) (((ee) >= MHI_EE_MAX) ? \
+			     "INVALID_EE" : mhi_ee_str[ee])
+
+#define MHI_IN_PBL(ee) (ee == MHI_EE_PBL || ee == MHI_EE_PTHRU || \
+			ee == MHI_EE_EDL)
+#define MHI_POWER_UP_CAPABLE(ee) (MHI_IN_PBL(ee) || ee == MHI_EE_AMSS)
+#define MHI_FW_LOAD_CAPABLE(ee) (ee == MHI_EE_PBL || ee == MHI_EE_EDL)
+#define MHI_IN_MISSION_MODE(ee) (ee == MHI_EE_AMSS || ee == MHI_EE_WFW || \
+				 ee == MHI_EE_FP)
+
+enum dev_st_transition {
+	DEV_ST_TRANSITION_PBL,
+	DEV_ST_TRANSITION_READY,
+	DEV_ST_TRANSITION_SBL,
+	DEV_ST_TRANSITION_MISSION_MODE,
+	DEV_ST_TRANSITION_FP,
+	DEV_ST_TRANSITION_SYS_ERR,
+	DEV_ST_TRANSITION_DISABLE,
+	DEV_ST_TRANSITION_MAX,
+};
+
+extern const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX];
+#define TO_DEV_STATE_TRANS_STR(state) (((state) >= DEV_ST_TRANSITION_MAX) ? \
+				"INVALID_STATE" : dev_state_tran_str[state])
+
+/* internal power states */
+enum mhi_pm_state {
+	MHI_PM_STATE_DISABLE,
+	MHI_PM_STATE_POR,
+	MHI_PM_STATE_M0,
+	MHI_PM_STATE_M2,
+	MHI_PM_STATE_M3_ENTER,
+	MHI_PM_STATE_M3,
+	MHI_PM_STATE_M3_EXIT,
+	MHI_PM_STATE_FW_DL_ERR,
+	MHI_PM_STATE_SYS_ERR_DETECT,
+	MHI_PM_STATE_SYS_ERR_PROCESS,
+	MHI_PM_STATE_SHUTDOWN_PROCESS,
+	MHI_PM_STATE_LD_ERR_FATAL_DETECT,
+	MHI_PM_STATE_MAX
+};
+
+#define MHI_PM_DISABLE					BIT(0)
+#define MHI_PM_POR					BIT(1)
+#define MHI_PM_M0					BIT(2)
+#define MHI_PM_M2					BIT(3)
+#define MHI_PM_M3_ENTER					BIT(4)
+#define MHI_PM_M3					BIT(5)
+#define MHI_PM_M3_EXIT					BIT(6)
+/* firmware download failure state */
+#define MHI_PM_FW_DL_ERR				BIT(7)
+#define MHI_PM_SYS_ERR_DETECT				BIT(8)
+#define MHI_PM_SYS_ERR_PROCESS				BIT(9)
+#define MHI_PM_SHUTDOWN_PROCESS				BIT(10)
+/* link not accessible */
+#define MHI_PM_LD_ERR_FATAL_DETECT			BIT(11)
+
+#define MHI_REG_ACCESS_VALID(pm_state)			((pm_state & (MHI_PM_POR | MHI_PM_M0 | \
+						MHI_PM_M2 | MHI_PM_M3_ENTER | MHI_PM_M3_EXIT | \
+						MHI_PM_SYS_ERR_DETECT | MHI_PM_SYS_ERR_PROCESS | \
+						MHI_PM_SHUTDOWN_PROCESS | MHI_PM_FW_DL_ERR)))
+#define MHI_PM_IN_ERROR_STATE(pm_state)			(pm_state >= MHI_PM_FW_DL_ERR)
+#define MHI_PM_IN_FATAL_STATE(pm_state)			(pm_state == MHI_PM_LD_ERR_FATAL_DETECT)
+#define MHI_DB_ACCESS_VALID(mhi_cntrl)			(mhi_cntrl->pm_state & mhi_cntrl->db_access)
+#define MHI_WAKE_DB_CLEAR_VALID(pm_state)		(pm_state & (MHI_PM_M0 | \
+							MHI_PM_M2 | MHI_PM_M3_EXIT))
+#define MHI_WAKE_DB_SET_VALID(pm_state)			(pm_state & MHI_PM_M2)
+#define MHI_WAKE_DB_FORCE_SET_VALID(pm_state)		MHI_WAKE_DB_CLEAR_VALID(pm_state)
+#define MHI_EVENT_ACCESS_INVALID(pm_state)		(pm_state == MHI_PM_DISABLE || \
+							MHI_PM_IN_ERROR_STATE(pm_state))
+#define MHI_PM_IN_SUSPEND_STATE(pm_state)		(pm_state & \
+							(MHI_PM_M3_ENTER | MHI_PM_M3))
+
+#define NR_OF_CMD_RINGS					1
+#define CMD_EL_PER_RING					128
+#define PRIMARY_CMD_RING				0
+#define MHI_DEV_WAKE_DB					127
+#define MHI_MAX_MTU					0xffff
+#define MHI_RANDOM_U32_NONZERO(bmsk)			(prandom_u32_max(bmsk) + 1)
+
+enum mhi_er_type {
+	MHI_ER_TYPE_INVALID = 0x0,
+	MHI_ER_TYPE_VALID = 0x1,
+};
+
+struct db_cfg {
+	bool reset_req;
+	bool db_mode;
+	u32 pollcfg;
+	enum mhi_db_brst_mode brstmode;
+	dma_addr_t db_val;
+	void (*process_db)(struct mhi_controller *mhi_cntrl,
+			   struct db_cfg *db_cfg, void __iomem *io_addr,
+			   dma_addr_t db_val);
+};
+
+struct mhi_pm_transitions {
+	enum mhi_pm_state from_state;
+	u32 to_states;
+};
+
+struct state_transition {
+	struct list_head node;
+	enum dev_st_transition state;
+};
+
+struct mhi_ring {
+	dma_addr_t dma_handle;
+	dma_addr_t iommu_base;
+	__le64 *ctxt_wp; /* point to ctxt wp */
+	void *pre_aligned;
+	void *base;
+	void *rp;
+	void *wp;
+	size_t el_size;
+	size_t len;
+	size_t elements;
+	size_t alloc_size;
+	void __iomem *db_addr;
+};
+
+struct mhi_cmd {
+	struct mhi_ring ring;
+	spinlock_t lock;
+};
+
+struct mhi_buf_info {
+	void *v_addr;
+	void *bb_addr;
+	void *wp;
+	void *cb_buf;
+	dma_addr_t p_addr;
+	size_t len;
+	enum dma_data_direction dir;
+	bool used; /* Indicates whether the buffer is used or not */
+	bool pre_mapped; /* Already pre-mapped by client */
+};
+
+struct mhi_event {
+	struct mhi_controller *mhi_cntrl;
+	struct mhi_chan *mhi_chan; /* dedicated to channel */
+	u32 er_index;
+	u32 intmod;
+	u32 irq;
+	int chan; /* this event ring is dedicated to a channel (optional) */
+	u32 priority;
+	enum mhi_er_data_type data_type;
+	struct mhi_ring ring;
+	struct db_cfg db_cfg;
+	struct tasklet_struct task;
+	spinlock_t lock;
+	int (*process_event)(struct mhi_controller *mhi_cntrl,
+			     struct mhi_event *mhi_event,
+			     u32 event_quota);
+	bool hw_ring;
+	bool cl_manage;
+	bool offload_ev; /* managed by a device driver */
+};
+
+struct mhi_chan {
+	const char *name;
+	/*
+	 * Important: When consuming, increment tre_ring first and when
+	 * releasing, decrement buf_ring first. If tre_ring has space, buf_ring
+	 * is guranteed to have space so we do not need to check both rings.
+	 */
+	struct mhi_ring buf_ring;
+	struct mhi_ring tre_ring;
+	u32 chan;
+	u32 er_index;
+	u32 intmod;
+	enum mhi_ch_type type;
+	enum dma_data_direction dir;
+	struct db_cfg db_cfg;
+	enum mhi_ch_ee_mask ee_mask;
+	enum mhi_ch_state ch_state;
+	enum mhi_ev_ccs ccs;
+	struct mhi_device *mhi_dev;
+	void (*xfer_cb)(struct mhi_device *mhi_dev, struct mhi_result *result);
+	struct mutex mutex;
+	struct completion completion;
+	rwlock_t lock;
+	struct list_head node;
+	bool lpm_notify;
+	bool configured;
+	bool offload_ch;
+	bool pre_alloc;
+	bool wake_capable;
+};
+
+/* Default MHI timeout */
+#define MHI_TIMEOUT_MS (1000)
+
+/* debugfs related functions */
+#ifdef CONFIG_MHI_BUS_DEBUG
+void mhi_create_debugfs(struct mhi_controller *mhi_cntrl);
+void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl);
+void mhi_debugfs_init(void);
+void mhi_debugfs_exit(void);
+#else
+static inline void mhi_create_debugfs(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static inline void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static inline void mhi_debugfs_init(void)
+{
+}
+
+static inline void mhi_debugfs_exit(void)
+{
+}
+#endif
+
+struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl);
+
+int mhi_destroy_device(struct device *dev, void *data);
+void mhi_create_devices(struct mhi_controller *mhi_cntrl);
+
+int mhi_alloc_bhie_table(struct mhi_controller *mhi_cntrl,
+			 struct image_info **image_info, size_t alloc_size);
+void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl,
+			 struct image_info *image_info);
+
+/* Power management APIs */
+enum mhi_pm_state __must_check mhi_tryset_pm_state(
+					struct mhi_controller *mhi_cntrl,
+					enum mhi_pm_state state);
+const char *to_mhi_pm_state_str(u32 state);
+int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
+			       enum dev_st_transition state);
+void mhi_pm_st_worker(struct work_struct *work);
+void mhi_pm_sys_err_handler(struct mhi_controller *mhi_cntrl);
+int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl);
+int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl);
+void mhi_pm_m1_transition(struct mhi_controller *mhi_cntrl);
+int mhi_pm_m3_transition(struct mhi_controller *mhi_cntrl);
+int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl);
+int mhi_send_cmd(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan,
+		 enum mhi_cmd_type cmd);
+int mhi_download_amss_image(struct mhi_controller *mhi_cntrl);
+static inline bool mhi_is_active(struct mhi_controller *mhi_cntrl)
+{
+	return (mhi_cntrl->dev_state >= MHI_STATE_M0 &&
+		mhi_cntrl->dev_state <= MHI_STATE_M3_FAST);
+}
+
+static inline void mhi_trigger_resume(struct mhi_controller *mhi_cntrl)
+{
+	pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
+	mhi_cntrl->runtime_get(mhi_cntrl);
+	mhi_cntrl->runtime_put(mhi_cntrl);
+}
+
+/* Register access methods */
+void mhi_db_brstmode(struct mhi_controller *mhi_cntrl, struct db_cfg *db_cfg,
+		     void __iomem *db_addr, dma_addr_t db_val);
+void mhi_db_brstmode_disable(struct mhi_controller *mhi_cntrl,
+			     struct db_cfg *db_mode, void __iomem *db_addr,
+			     dma_addr_t db_val);
+int __must_check mhi_read_reg(struct mhi_controller *mhi_cntrl,
+			      void __iomem *base, u32 offset, u32 *out);
+int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset, u32 mask,
+				    u32 *out);
+int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset, u32 mask,
+				    u32 val, u32 delayus);
+void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,
+		   u32 offset, u32 val);
+int __must_check mhi_write_reg_field(struct mhi_controller *mhi_cntrl,
+				     void __iomem *base, u32 offset, u32 mask,
+				     u32 val);
+void mhi_ring_er_db(struct mhi_event *mhi_event);
+void mhi_write_db(struct mhi_controller *mhi_cntrl, void __iomem *db_addr,
+		  dma_addr_t db_val);
+void mhi_ring_cmd_db(struct mhi_controller *mhi_cntrl, struct mhi_cmd *mhi_cmd);
+void mhi_ring_chan_db(struct mhi_controller *mhi_cntrl,
+		      struct mhi_chan *mhi_chan);
+
+/* Initialization methods */
+int mhi_init_mmio(struct mhi_controller *mhi_cntrl);
+int mhi_init_dev_ctxt(struct mhi_controller *mhi_cntrl);
+void mhi_deinit_dev_ctxt(struct mhi_controller *mhi_cntrl);
+int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl);
+void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl);
+int mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
+		      struct image_info *img_info);
+void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl);
+
+/* Automatically allocate and queue inbound buffers */
+#define MHI_CH_INBOUND_ALLOC_BUFS BIT(0)
+int mhi_prepare_channel(struct mhi_controller *mhi_cntrl,
+			struct mhi_chan *mhi_chan, unsigned int flags);
+
+int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
+		       struct mhi_chan *mhi_chan);
+void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
+			  struct mhi_chan *mhi_chan);
+void mhi_reset_chan(struct mhi_controller *mhi_cntrl,
+		    struct mhi_chan *mhi_chan);
+
+/* Event processing methods */
+void mhi_ctrl_ev_task(unsigned long data);
+void mhi_ev_task(unsigned long data);
+int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl,
+				struct mhi_event *mhi_event, u32 event_quota);
+int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl,
+			     struct mhi_event *mhi_event, u32 event_quota);
+
+/* ISR handlers */
+irqreturn_t mhi_irq_handler(int irq_number, void *dev);
+irqreturn_t mhi_intvec_threaded_handler(int irq_number, void *dev);
+irqreturn_t mhi_intvec_handler(int irq_number, void *dev);
+
+int mhi_gen_tre(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan,
+		struct mhi_buf_info *info, enum mhi_flags flags);
+int mhi_map_single_no_bb(struct mhi_controller *mhi_cntrl,
+			 struct mhi_buf_info *buf_info);
+int mhi_map_single_use_bb(struct mhi_controller *mhi_cntrl,
+			  struct mhi_buf_info *buf_info);
+void mhi_unmap_single_no_bb(struct mhi_controller *mhi_cntrl,
+			    struct mhi_buf_info *buf_info);
+void mhi_unmap_single_use_bb(struct mhi_controller *mhi_cntrl,
+			     struct mhi_buf_info *buf_info);
+
+#endif /* _MHI_INT_H */
diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c
new file mode 100644
index 000000000..8378c3319
--- /dev/null
+++ b/drivers/bus/mhi/host/main.c
@@ -0,0 +1,1705 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+int __must_check mhi_read_reg(struct mhi_controller *mhi_cntrl,
+			      void __iomem *base, u32 offset, u32 *out)
+{
+	return mhi_cntrl->read_reg(mhi_cntrl, base + offset, out);
+}
+
+int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset,
+				    u32 mask, u32 *out)
+{
+	u32 tmp;
+	int ret;
+
+	ret = mhi_read_reg(mhi_cntrl, base, offset, &tmp);
+	if (ret)
+		return ret;
+
+	*out = (tmp & mask) >> __ffs(mask);
+
+	return 0;
+}
+
+int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset,
+				    u32 mask, u32 val, u32 delayus)
+{
+	int ret;
+	u32 out, retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
+
+	while (retry--) {
+		ret = mhi_read_reg_field(mhi_cntrl, base, offset, mask, &out);
+		if (ret)
+			return ret;
+
+		if (out == val)
+			return 0;
+
+		fsleep(delayus);
+	}
+
+	return -ETIMEDOUT;
+}
+
+void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,
+		   u32 offset, u32 val)
+{
+	mhi_cntrl->write_reg(mhi_cntrl, base + offset, val);
+}
+
+int __must_check mhi_write_reg_field(struct mhi_controller *mhi_cntrl,
+				     void __iomem *base, u32 offset, u32 mask,
+				     u32 val)
+{
+	int ret;
+	u32 tmp;
+
+	ret = mhi_read_reg(mhi_cntrl, base, offset, &tmp);
+	if (ret)
+		return ret;
+
+	tmp &= ~mask;
+	tmp |= (val << __ffs(mask));
+	mhi_write_reg(mhi_cntrl, base, offset, tmp);
+
+	return 0;
+}
+
+void mhi_write_db(struct mhi_controller *mhi_cntrl, void __iomem *db_addr,
+		  dma_addr_t db_val)
+{
+	mhi_write_reg(mhi_cntrl, db_addr, 4, upper_32_bits(db_val));
+	mhi_write_reg(mhi_cntrl, db_addr, 0, lower_32_bits(db_val));
+}
+
+void mhi_db_brstmode(struct mhi_controller *mhi_cntrl,
+		     struct db_cfg *db_cfg,
+		     void __iomem *db_addr,
+		     dma_addr_t db_val)
+{
+	if (db_cfg->db_mode) {
+		db_cfg->db_val = db_val;
+		mhi_write_db(mhi_cntrl, db_addr, db_val);
+		db_cfg->db_mode = 0;
+	}
+}
+
+void mhi_db_brstmode_disable(struct mhi_controller *mhi_cntrl,
+			     struct db_cfg *db_cfg,
+			     void __iomem *db_addr,
+			     dma_addr_t db_val)
+{
+	db_cfg->db_val = db_val;
+	mhi_write_db(mhi_cntrl, db_addr, db_val);
+}
+
+void mhi_ring_er_db(struct mhi_event *mhi_event)
+{
+	struct mhi_ring *ring = &mhi_event->ring;
+
+	mhi_event->db_cfg.process_db(mhi_event->mhi_cntrl, &mhi_event->db_cfg,
+				     ring->db_addr, le64_to_cpu(*ring->ctxt_wp));
+}
+
+void mhi_ring_cmd_db(struct mhi_controller *mhi_cntrl, struct mhi_cmd *mhi_cmd)
+{
+	dma_addr_t db;
+	struct mhi_ring *ring = &mhi_cmd->ring;
+
+	db = ring->iommu_base + (ring->wp - ring->base);
+	*ring->ctxt_wp = cpu_to_le64(db);
+	mhi_write_db(mhi_cntrl, ring->db_addr, db);
+}
+
+void mhi_ring_chan_db(struct mhi_controller *mhi_cntrl,
+		      struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *ring = &mhi_chan->tre_ring;
+	dma_addr_t db;
+
+	db = ring->iommu_base + (ring->wp - ring->base);
+
+	/*
+	 * Writes to the new ring element must be visible to the hardware
+	 * before letting h/w know there is new element to fetch.
+	 */
+	dma_wmb();
+	*ring->ctxt_wp = cpu_to_le64(db);
+
+	mhi_chan->db_cfg.process_db(mhi_cntrl, &mhi_chan->db_cfg,
+				    ring->db_addr, db);
+}
+
+enum mhi_ee_type mhi_get_exec_env(struct mhi_controller *mhi_cntrl)
+{
+	u32 exec;
+	int ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_EXECENV, &exec);
+
+	return (ret) ? MHI_EE_MAX : exec;
+}
+EXPORT_SYMBOL_GPL(mhi_get_exec_env);
+
+enum mhi_state mhi_get_mhi_state(struct mhi_controller *mhi_cntrl)
+{
+	u32 state;
+	int ret = mhi_read_reg_field(mhi_cntrl, mhi_cntrl->regs, MHISTATUS,
+				     MHISTATUS_MHISTATE_MASK, &state);
+	return ret ? MHI_STATE_MAX : state;
+}
+EXPORT_SYMBOL_GPL(mhi_get_mhi_state);
+
+void mhi_soc_reset(struct mhi_controller *mhi_cntrl)
+{
+	if (mhi_cntrl->reset) {
+		mhi_cntrl->reset(mhi_cntrl);
+		return;
+	}
+
+	/* Generic MHI SoC reset */
+	mhi_write_reg(mhi_cntrl, mhi_cntrl->regs, MHI_SOC_RESET_REQ_OFFSET,
+		      MHI_SOC_RESET_REQ);
+}
+EXPORT_SYMBOL_GPL(mhi_soc_reset);
+
+int mhi_map_single_no_bb(struct mhi_controller *mhi_cntrl,
+			 struct mhi_buf_info *buf_info)
+{
+	buf_info->p_addr = dma_map_single(mhi_cntrl->cntrl_dev,
+					  buf_info->v_addr, buf_info->len,
+					  buf_info->dir);
+	if (dma_mapping_error(mhi_cntrl->cntrl_dev, buf_info->p_addr))
+		return -ENOMEM;
+
+	return 0;
+}
+
+int mhi_map_single_use_bb(struct mhi_controller *mhi_cntrl,
+			  struct mhi_buf_info *buf_info)
+{
+	void *buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev, buf_info->len,
+				       &buf_info->p_addr, GFP_ATOMIC);
+
+	if (!buf)
+		return -ENOMEM;
+
+	if (buf_info->dir == DMA_TO_DEVICE)
+		memcpy(buf, buf_info->v_addr, buf_info->len);
+
+	buf_info->bb_addr = buf;
+
+	return 0;
+}
+
+void mhi_unmap_single_no_bb(struct mhi_controller *mhi_cntrl,
+			    struct mhi_buf_info *buf_info)
+{
+	dma_unmap_single(mhi_cntrl->cntrl_dev, buf_info->p_addr, buf_info->len,
+			 buf_info->dir);
+}
+
+void mhi_unmap_single_use_bb(struct mhi_controller *mhi_cntrl,
+			     struct mhi_buf_info *buf_info)
+{
+	if (buf_info->dir == DMA_FROM_DEVICE)
+		memcpy(buf_info->v_addr, buf_info->bb_addr, buf_info->len);
+
+	dma_free_coherent(mhi_cntrl->cntrl_dev, buf_info->len,
+			  buf_info->bb_addr, buf_info->p_addr);
+}
+
+static int get_nr_avail_ring_elements(struct mhi_controller *mhi_cntrl,
+				      struct mhi_ring *ring)
+{
+	int nr_el;
+
+	if (ring->wp < ring->rp) {
+		nr_el = ((ring->rp - ring->wp) / ring->el_size) - 1;
+	} else {
+		nr_el = (ring->rp - ring->base) / ring->el_size;
+		nr_el += ((ring->base + ring->len - ring->wp) /
+			  ring->el_size) - 1;
+	}
+
+	return nr_el;
+}
+
+static void *mhi_to_virtual(struct mhi_ring *ring, dma_addr_t addr)
+{
+	return (addr - ring->iommu_base) + ring->base;
+}
+
+static void mhi_add_ring_element(struct mhi_controller *mhi_cntrl,
+				 struct mhi_ring *ring)
+{
+	ring->wp += ring->el_size;
+	if (ring->wp >= (ring->base + ring->len))
+		ring->wp = ring->base;
+	/* smp update */
+	smp_wmb();
+}
+
+static void mhi_del_ring_element(struct mhi_controller *mhi_cntrl,
+				 struct mhi_ring *ring)
+{
+	ring->rp += ring->el_size;
+	if (ring->rp >= (ring->base + ring->len))
+		ring->rp = ring->base;
+	/* smp update */
+	smp_wmb();
+}
+
+static bool is_valid_ring_ptr(struct mhi_ring *ring, dma_addr_t addr)
+{
+	return addr >= ring->iommu_base && addr < ring->iommu_base + ring->len &&
+			!(addr & (sizeof(struct mhi_ring_element) - 1));
+}
+
+int mhi_destroy_device(struct device *dev, void *data)
+{
+	struct mhi_chan *ul_chan, *dl_chan;
+	struct mhi_device *mhi_dev;
+	struct mhi_controller *mhi_cntrl;
+	enum mhi_ee_type ee = MHI_EE_MAX;
+
+	if (dev->bus != &mhi_bus_type)
+		return 0;
+
+	mhi_dev = to_mhi_device(dev);
+	mhi_cntrl = mhi_dev->mhi_cntrl;
+
+	/* Only destroy virtual devices thats attached to bus */
+	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
+		return 0;
+
+	ul_chan = mhi_dev->ul_chan;
+	dl_chan = mhi_dev->dl_chan;
+
+	/*
+	 * If execution environment is specified, remove only those devices that
+	 * started in them based on ee_mask for the channels as we move on to a
+	 * different execution environment
+	 */
+	if (data)
+		ee = *(enum mhi_ee_type *)data;
+
+	/*
+	 * For the suspend and resume case, this function will get called
+	 * without mhi_unregister_controller(). Hence, we need to drop the
+	 * references to mhi_dev created for ul and dl channels. We can
+	 * be sure that there will be no instances of mhi_dev left after
+	 * this.
+	 */
+	if (ul_chan) {
+		if (ee != MHI_EE_MAX && !(ul_chan->ee_mask & BIT(ee)))
+			return 0;
+
+		put_device(&ul_chan->mhi_dev->dev);
+	}
+
+	if (dl_chan) {
+		if (ee != MHI_EE_MAX && !(dl_chan->ee_mask & BIT(ee)))
+			return 0;
+
+		put_device(&dl_chan->mhi_dev->dev);
+	}
+
+	dev_dbg(&mhi_cntrl->mhi_dev->dev, "destroy device for chan:%s\n",
+		 mhi_dev->name);
+
+	/* Notify the client and remove the device from MHI bus */
+	device_del(dev);
+	put_device(dev);
+
+	return 0;
+}
+
+int mhi_get_free_desc_count(struct mhi_device *mhi_dev,
+				enum dma_data_direction dir)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ?
+		mhi_dev->ul_chan : mhi_dev->dl_chan;
+	struct mhi_ring *tre_ring = &mhi_chan->tre_ring;
+
+	return get_nr_avail_ring_elements(mhi_cntrl, tre_ring);
+}
+EXPORT_SYMBOL_GPL(mhi_get_free_desc_count);
+
+void mhi_notify(struct mhi_device *mhi_dev, enum mhi_callback cb_reason)
+{
+	struct mhi_driver *mhi_drv;
+
+	if (!mhi_dev->dev.driver)
+		return;
+
+	mhi_drv = to_mhi_driver(mhi_dev->dev.driver);
+
+	if (mhi_drv->status_cb)
+		mhi_drv->status_cb(mhi_dev, cb_reason);
+}
+EXPORT_SYMBOL_GPL(mhi_notify);
+
+/* Bind MHI channels to MHI devices */
+void mhi_create_devices(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_chan *mhi_chan;
+	struct mhi_device *mhi_dev;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int i, ret;
+
+	mhi_chan = mhi_cntrl->mhi_chan;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
+		if (!mhi_chan->configured || mhi_chan->mhi_dev ||
+		    !(mhi_chan->ee_mask & BIT(mhi_cntrl->ee)))
+			continue;
+		mhi_dev = mhi_alloc_device(mhi_cntrl);
+		if (IS_ERR(mhi_dev))
+			return;
+
+		mhi_dev->dev_type = MHI_DEVICE_XFER;
+		switch (mhi_chan->dir) {
+		case DMA_TO_DEVICE:
+			mhi_dev->ul_chan = mhi_chan;
+			mhi_dev->ul_chan_id = mhi_chan->chan;
+			break;
+		case DMA_FROM_DEVICE:
+			/* We use dl_chan as offload channels */
+			mhi_dev->dl_chan = mhi_chan;
+			mhi_dev->dl_chan_id = mhi_chan->chan;
+			break;
+		default:
+			dev_err(dev, "Direction not supported\n");
+			put_device(&mhi_dev->dev);
+			return;
+		}
+
+		get_device(&mhi_dev->dev);
+		mhi_chan->mhi_dev = mhi_dev;
+
+		/* Check next channel if it matches */
+		if ((i + 1) < mhi_cntrl->max_chan && mhi_chan[1].configured) {
+			if (!strcmp(mhi_chan[1].name, mhi_chan->name)) {
+				i++;
+				mhi_chan++;
+				if (mhi_chan->dir == DMA_TO_DEVICE) {
+					mhi_dev->ul_chan = mhi_chan;
+					mhi_dev->ul_chan_id = mhi_chan->chan;
+				} else {
+					mhi_dev->dl_chan = mhi_chan;
+					mhi_dev->dl_chan_id = mhi_chan->chan;
+				}
+				get_device(&mhi_dev->dev);
+				mhi_chan->mhi_dev = mhi_dev;
+			}
+		}
+
+		/* Channel name is same for both UL and DL */
+		mhi_dev->name = mhi_chan->name;
+		dev_set_name(&mhi_dev->dev, "%s_%s",
+			     dev_name(&mhi_cntrl->mhi_dev->dev),
+			     mhi_dev->name);
+
+		/* Init wakeup source if available */
+		if (mhi_dev->dl_chan && mhi_dev->dl_chan->wake_capable)
+			device_init_wakeup(&mhi_dev->dev, true);
+
+		ret = device_add(&mhi_dev->dev);
+		if (ret)
+			put_device(&mhi_dev->dev);
+	}
+}
+
+irqreturn_t mhi_irq_handler(int irq_number, void *dev)
+{
+	struct mhi_event *mhi_event = dev;
+	struct mhi_controller *mhi_cntrl = mhi_event->mhi_cntrl;
+	struct mhi_event_ctxt *er_ctxt;
+	struct mhi_ring *ev_ring = &mhi_event->ring;
+	dma_addr_t ptr;
+	void *dev_rp;
+
+	/*
+	 * If CONFIG_DEBUG_SHIRQ is set, the IRQ handler will get invoked during __free_irq()
+	 * and by that time mhi_ctxt() would've freed. So check for the existence of mhi_ctxt
+	 * before handling the IRQs.
+	 */
+	if (!mhi_cntrl->mhi_ctxt) {
+		dev_dbg(&mhi_cntrl->mhi_dev->dev,
+			"mhi_ctxt has been freed\n");
+		return IRQ_HANDLED;
+	}
+
+	er_ctxt = &mhi_cntrl->mhi_ctxt->er_ctxt[mhi_event->er_index];
+	ptr = le64_to_cpu(er_ctxt->rp);
+
+	if (!is_valid_ring_ptr(ev_ring, ptr)) {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Event ring rp points outside of the event ring\n");
+		return IRQ_HANDLED;
+	}
+
+	dev_rp = mhi_to_virtual(ev_ring, ptr);
+
+	/* Only proceed if event ring has pending events */
+	if (ev_ring->rp == dev_rp)
+		return IRQ_HANDLED;
+
+	/* For client managed event ring, notify pending data */
+	if (mhi_event->cl_manage) {
+		struct mhi_chan *mhi_chan = mhi_event->mhi_chan;
+		struct mhi_device *mhi_dev = mhi_chan->mhi_dev;
+
+		if (mhi_dev)
+			mhi_notify(mhi_dev, MHI_CB_PENDING_DATA);
+	} else {
+		tasklet_schedule(&mhi_event->task);
+	}
+
+	return IRQ_HANDLED;
+}
+
+irqreturn_t mhi_intvec_threaded_handler(int irq_number, void *priv)
+{
+	struct mhi_controller *mhi_cntrl = priv;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_state state;
+	enum mhi_pm_state pm_state = 0;
+	enum mhi_ee_type ee;
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		goto exit_intvec;
+	}
+
+	state = mhi_get_mhi_state(mhi_cntrl);
+	ee = mhi_get_exec_env(mhi_cntrl);
+	dev_dbg(dev, "local ee: %s state: %s device ee: %s state: %s\n",
+		TO_MHI_EXEC_STR(mhi_cntrl->ee),
+		mhi_state_str(mhi_cntrl->dev_state),
+		TO_MHI_EXEC_STR(ee), mhi_state_str(state));
+
+	if (state == MHI_STATE_SYS_ERR) {
+		dev_dbg(dev, "System error detected\n");
+		pm_state = mhi_tryset_pm_state(mhi_cntrl,
+					       MHI_PM_SYS_ERR_DETECT);
+	}
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	if (pm_state != MHI_PM_SYS_ERR_DETECT)
+		goto exit_intvec;
+
+	switch (ee) {
+	case MHI_EE_RDDM:
+		/* proceed if power down is not already in progress */
+		if (mhi_cntrl->rddm_image && mhi_is_active(mhi_cntrl)) {
+			mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_EE_RDDM);
+			mhi_cntrl->ee = ee;
+			wake_up_all(&mhi_cntrl->state_event);
+		}
+		break;
+	case MHI_EE_PBL:
+	case MHI_EE_EDL:
+	case MHI_EE_PTHRU:
+		mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_FATAL_ERROR);
+		mhi_cntrl->ee = ee;
+		wake_up_all(&mhi_cntrl->state_event);
+		mhi_pm_sys_err_handler(mhi_cntrl);
+		break;
+	default:
+		wake_up_all(&mhi_cntrl->state_event);
+		mhi_pm_sys_err_handler(mhi_cntrl);
+		break;
+	}
+
+exit_intvec:
+
+	return IRQ_HANDLED;
+}
+
+irqreturn_t mhi_intvec_handler(int irq_number, void *dev)
+{
+	struct mhi_controller *mhi_cntrl = dev;
+
+	/* Wake up events waiting for state change */
+	wake_up_all(&mhi_cntrl->state_event);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static void mhi_recycle_ev_ring_element(struct mhi_controller *mhi_cntrl,
+					struct mhi_ring *ring)
+{
+	/* Update the WP */
+	ring->wp += ring->el_size;
+
+	if (ring->wp >= (ring->base + ring->len))
+		ring->wp = ring->base;
+
+	*ring->ctxt_wp = cpu_to_le64(ring->iommu_base + (ring->wp - ring->base));
+
+	/* Update the RP */
+	ring->rp += ring->el_size;
+	if (ring->rp >= (ring->base + ring->len))
+		ring->rp = ring->base;
+
+	/* Update to all cores */
+	smp_wmb();
+}
+
+static int parse_xfer_event(struct mhi_controller *mhi_cntrl,
+			    struct mhi_ring_element *event,
+			    struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *buf_ring, *tre_ring;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	struct mhi_result result;
+	unsigned long flags = 0;
+	u32 ev_code;
+
+	ev_code = MHI_TRE_GET_EV_CODE(event);
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+
+	result.transaction_status = (ev_code == MHI_EV_CC_OVERFLOW) ?
+		-EOVERFLOW : 0;
+
+	/*
+	 * If it's a DB Event then we need to grab the lock
+	 * with preemption disabled and as a write because we
+	 * have to update db register and there are chances that
+	 * another thread could be doing the same.
+	 */
+	if (ev_code >= MHI_EV_CC_OOB)
+		write_lock_irqsave(&mhi_chan->lock, flags);
+	else
+		read_lock_bh(&mhi_chan->lock);
+
+	if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED)
+		goto end_process_tx_event;
+
+	switch (ev_code) {
+	case MHI_EV_CC_OVERFLOW:
+	case MHI_EV_CC_EOB:
+	case MHI_EV_CC_EOT:
+	{
+		dma_addr_t ptr = MHI_TRE_GET_EV_PTR(event);
+		struct mhi_ring_element *local_rp, *ev_tre;
+		void *dev_rp;
+		struct mhi_buf_info *buf_info;
+		u16 xfer_len;
+
+		if (!is_valid_ring_ptr(tre_ring, ptr)) {
+			dev_err(&mhi_cntrl->mhi_dev->dev,
+				"Event element points outside of the tre ring\n");
+			break;
+		}
+		/* Get the TRB this event points to */
+		ev_tre = mhi_to_virtual(tre_ring, ptr);
+
+		dev_rp = ev_tre + 1;
+		if (dev_rp >= (tre_ring->base + tre_ring->len))
+			dev_rp = tre_ring->base;
+
+		result.dir = mhi_chan->dir;
+
+		local_rp = tre_ring->rp;
+		while (local_rp != dev_rp) {
+			buf_info = buf_ring->rp;
+			/* If it's the last TRE, get length from the event */
+			if (local_rp == ev_tre)
+				xfer_len = MHI_TRE_GET_EV_LEN(event);
+			else
+				xfer_len = buf_info->len;
+
+			/* Unmap if it's not pre-mapped by client */
+			if (likely(!buf_info->pre_mapped))
+				mhi_cntrl->unmap_single(mhi_cntrl, buf_info);
+
+			result.buf_addr = buf_info->cb_buf;
+
+			/* truncate to buf len if xfer_len is larger */
+			result.bytes_xferd =
+				min_t(u16, xfer_len, buf_info->len);
+			mhi_del_ring_element(mhi_cntrl, buf_ring);
+			mhi_del_ring_element(mhi_cntrl, tre_ring);
+			local_rp = tre_ring->rp;
+
+			read_unlock_bh(&mhi_chan->lock);
+
+			/* notify client */
+			mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
+
+			if (mhi_chan->dir == DMA_TO_DEVICE) {
+				atomic_dec(&mhi_cntrl->pending_pkts);
+				/* Release the reference got from mhi_queue() */
+				mhi_cntrl->runtime_put(mhi_cntrl);
+			}
+
+			/*
+			 * Recycle the buffer if buffer is pre-allocated,
+			 * if there is an error, not much we can do apart
+			 * from dropping the packet
+			 */
+			if (mhi_chan->pre_alloc) {
+				if (mhi_queue_buf(mhi_chan->mhi_dev,
+						  mhi_chan->dir,
+						  buf_info->cb_buf,
+						  buf_info->len, MHI_EOT)) {
+					dev_err(dev,
+						"Error recycling buffer for chan:%d\n",
+						mhi_chan->chan);
+					kfree(buf_info->cb_buf);
+				}
+			}
+
+			read_lock_bh(&mhi_chan->lock);
+		}
+		break;
+	} /* CC_EOT */
+	case MHI_EV_CC_OOB:
+	case MHI_EV_CC_DB_MODE:
+	{
+		unsigned long pm_lock_flags;
+
+		mhi_chan->db_cfg.db_mode = 1;
+		read_lock_irqsave(&mhi_cntrl->pm_lock, pm_lock_flags);
+		if (tre_ring->wp != tre_ring->rp &&
+		    MHI_DB_ACCESS_VALID(mhi_cntrl)) {
+			mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+		}
+		read_unlock_irqrestore(&mhi_cntrl->pm_lock, pm_lock_flags);
+		break;
+	}
+	case MHI_EV_CC_BAD_TRE:
+	default:
+		dev_err(dev, "Unknown event 0x%x\n", ev_code);
+		break;
+	} /* switch(MHI_EV_READ_CODE(EV_TRB_CODE,event)) */
+
+end_process_tx_event:
+	if (ev_code >= MHI_EV_CC_OOB)
+		write_unlock_irqrestore(&mhi_chan->lock, flags);
+	else
+		read_unlock_bh(&mhi_chan->lock);
+
+	return 0;
+}
+
+static int parse_rsc_event(struct mhi_controller *mhi_cntrl,
+			   struct mhi_ring_element *event,
+			   struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *buf_ring, *tre_ring;
+	struct mhi_buf_info *buf_info;
+	struct mhi_result result;
+	int ev_code;
+	u32 cookie; /* offset to local descriptor */
+	u16 xfer_len;
+
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+
+	ev_code = MHI_TRE_GET_EV_CODE(event);
+	cookie = MHI_TRE_GET_EV_COOKIE(event);
+	xfer_len = MHI_TRE_GET_EV_LEN(event);
+
+	/* Received out of bound cookie */
+	WARN_ON(cookie >= buf_ring->len);
+
+	buf_info = buf_ring->base + cookie;
+
+	result.transaction_status = (ev_code == MHI_EV_CC_OVERFLOW) ?
+		-EOVERFLOW : 0;
+
+	/* truncate to buf len if xfer_len is larger */
+	result.bytes_xferd = min_t(u16, xfer_len, buf_info->len);
+	result.buf_addr = buf_info->cb_buf;
+	result.dir = mhi_chan->dir;
+
+	read_lock_bh(&mhi_chan->lock);
+
+	if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED)
+		goto end_process_rsc_event;
+
+	WARN_ON(!buf_info->used);
+
+	/* notify the client */
+	mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
+
+	/*
+	 * Note: We're arbitrarily incrementing RP even though, completion
+	 * packet we processed might not be the same one, reason we can do this
+	 * is because device guaranteed to cache descriptors in order it
+	 * receive, so even though completion event is different we can re-use
+	 * all descriptors in between.
+	 * Example:
+	 * Transfer Ring has descriptors: A, B, C, D
+	 * Last descriptor host queue is D (WP) and first descriptor
+	 * host queue is A (RP).
+	 * The completion event we just serviced is descriptor C.
+	 * Then we can safely queue descriptors to replace A, B, and C
+	 * even though host did not receive any completions.
+	 */
+	mhi_del_ring_element(mhi_cntrl, tre_ring);
+	buf_info->used = false;
+
+end_process_rsc_event:
+	read_unlock_bh(&mhi_chan->lock);
+
+	return 0;
+}
+
+static void mhi_process_cmd_completion(struct mhi_controller *mhi_cntrl,
+				       struct mhi_ring_element *tre)
+{
+	dma_addr_t ptr = MHI_TRE_GET_EV_PTR(tre);
+	struct mhi_cmd *cmd_ring = &mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING];
+	struct mhi_ring *mhi_ring = &cmd_ring->ring;
+	struct mhi_ring_element *cmd_pkt;
+	struct mhi_chan *mhi_chan;
+	u32 chan;
+
+	if (!is_valid_ring_ptr(mhi_ring, ptr)) {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Event element points outside of the cmd ring\n");
+		return;
+	}
+
+	cmd_pkt = mhi_to_virtual(mhi_ring, ptr);
+
+	chan = MHI_TRE_GET_CMD_CHID(cmd_pkt);
+
+	if (chan < mhi_cntrl->max_chan &&
+	    mhi_cntrl->mhi_chan[chan].configured) {
+		mhi_chan = &mhi_cntrl->mhi_chan[chan];
+		write_lock_bh(&mhi_chan->lock);
+		mhi_chan->ccs = MHI_TRE_GET_EV_CODE(tre);
+		complete(&mhi_chan->completion);
+		write_unlock_bh(&mhi_chan->lock);
+	} else {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Completion packet for invalid channel ID: %d\n", chan);
+	}
+
+	mhi_del_ring_element(mhi_cntrl, mhi_ring);
+}
+
+int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl,
+			     struct mhi_event *mhi_event,
+			     u32 event_quota)
+{
+	struct mhi_ring_element *dev_rp, *local_rp;
+	struct mhi_ring *ev_ring = &mhi_event->ring;
+	struct mhi_event_ctxt *er_ctxt =
+		&mhi_cntrl->mhi_ctxt->er_ctxt[mhi_event->er_index];
+	struct mhi_chan *mhi_chan;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 chan;
+	int count = 0;
+	dma_addr_t ptr = le64_to_cpu(er_ctxt->rp);
+
+	/*
+	 * This is a quick check to avoid unnecessary event processing
+	 * in case MHI is already in error state, but it's still possible
+	 * to transition to error state while processing events
+	 */
+	if (unlikely(MHI_EVENT_ACCESS_INVALID(mhi_cntrl->pm_state)))
+		return -EIO;
+
+	if (!is_valid_ring_ptr(ev_ring, ptr)) {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Event ring rp points outside of the event ring\n");
+		return -EIO;
+	}
+
+	dev_rp = mhi_to_virtual(ev_ring, ptr);
+	local_rp = ev_ring->rp;
+
+	while (dev_rp != local_rp) {
+		enum mhi_pkt_type type = MHI_TRE_GET_EV_TYPE(local_rp);
+
+		switch (type) {
+		case MHI_PKT_TYPE_BW_REQ_EVENT:
+		{
+			struct mhi_link_info *link_info;
+
+			link_info = &mhi_cntrl->mhi_link_info;
+			write_lock_irq(&mhi_cntrl->pm_lock);
+			link_info->target_link_speed =
+				MHI_TRE_GET_EV_LINKSPEED(local_rp);
+			link_info->target_link_width =
+				MHI_TRE_GET_EV_LINKWIDTH(local_rp);
+			write_unlock_irq(&mhi_cntrl->pm_lock);
+			dev_dbg(dev, "Received BW_REQ event\n");
+			mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_BW_REQ);
+			break;
+		}
+		case MHI_PKT_TYPE_STATE_CHANGE_EVENT:
+		{
+			enum mhi_state new_state;
+
+			new_state = MHI_TRE_GET_EV_STATE(local_rp);
+
+			dev_dbg(dev, "State change event to state: %s\n",
+				mhi_state_str(new_state));
+
+			switch (new_state) {
+			case MHI_STATE_M0:
+				mhi_pm_m0_transition(mhi_cntrl);
+				break;
+			case MHI_STATE_M1:
+				mhi_pm_m1_transition(mhi_cntrl);
+				break;
+			case MHI_STATE_M3:
+				mhi_pm_m3_transition(mhi_cntrl);
+				break;
+			case MHI_STATE_SYS_ERR:
+			{
+				enum mhi_pm_state pm_state;
+
+				dev_dbg(dev, "System error detected\n");
+				write_lock_irq(&mhi_cntrl->pm_lock);
+				pm_state = mhi_tryset_pm_state(mhi_cntrl,
+							MHI_PM_SYS_ERR_DETECT);
+				write_unlock_irq(&mhi_cntrl->pm_lock);
+				if (pm_state == MHI_PM_SYS_ERR_DETECT)
+					mhi_pm_sys_err_handler(mhi_cntrl);
+				break;
+			}
+			default:
+				dev_err(dev, "Invalid state: %s\n",
+					mhi_state_str(new_state));
+			}
+
+			break;
+		}
+		case MHI_PKT_TYPE_CMD_COMPLETION_EVENT:
+			mhi_process_cmd_completion(mhi_cntrl, local_rp);
+			break;
+		case MHI_PKT_TYPE_EE_EVENT:
+		{
+			enum dev_st_transition st = DEV_ST_TRANSITION_MAX;
+			enum mhi_ee_type event = MHI_TRE_GET_EV_EXECENV(local_rp);
+
+			dev_dbg(dev, "Received EE event: %s\n",
+				TO_MHI_EXEC_STR(event));
+			switch (event) {
+			case MHI_EE_SBL:
+				st = DEV_ST_TRANSITION_SBL;
+				break;
+			case MHI_EE_WFW:
+			case MHI_EE_AMSS:
+				st = DEV_ST_TRANSITION_MISSION_MODE;
+				break;
+			case MHI_EE_FP:
+				st = DEV_ST_TRANSITION_FP;
+				break;
+			case MHI_EE_RDDM:
+				mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_EE_RDDM);
+				write_lock_irq(&mhi_cntrl->pm_lock);
+				mhi_cntrl->ee = event;
+				write_unlock_irq(&mhi_cntrl->pm_lock);
+				wake_up_all(&mhi_cntrl->state_event);
+				break;
+			default:
+				dev_err(dev,
+					"Unhandled EE event: 0x%x\n", type);
+			}
+			if (st != DEV_ST_TRANSITION_MAX)
+				mhi_queue_state_transition(mhi_cntrl, st);
+
+			break;
+		}
+		case MHI_PKT_TYPE_TX_EVENT:
+			chan = MHI_TRE_GET_EV_CHID(local_rp);
+
+			WARN_ON(chan >= mhi_cntrl->max_chan);
+
+			/*
+			 * Only process the event ring elements whose channel
+			 * ID is within the maximum supported range.
+			 */
+			if (chan < mhi_cntrl->max_chan) {
+				mhi_chan = &mhi_cntrl->mhi_chan[chan];
+				if (!mhi_chan->configured)
+					break;
+				parse_xfer_event(mhi_cntrl, local_rp, mhi_chan);
+				event_quota--;
+			}
+			break;
+		default:
+			dev_err(dev, "Unhandled event type: %d\n", type);
+			break;
+		}
+
+		mhi_recycle_ev_ring_element(mhi_cntrl, ev_ring);
+		local_rp = ev_ring->rp;
+
+		ptr = le64_to_cpu(er_ctxt->rp);
+		if (!is_valid_ring_ptr(ev_ring, ptr)) {
+			dev_err(&mhi_cntrl->mhi_dev->dev,
+				"Event ring rp points outside of the event ring\n");
+			return -EIO;
+		}
+
+		dev_rp = mhi_to_virtual(ev_ring, ptr);
+		count++;
+	}
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)))
+		mhi_ring_er_db(mhi_event);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	return count;
+}
+
+int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl,
+				struct mhi_event *mhi_event,
+				u32 event_quota)
+{
+	struct mhi_ring_element *dev_rp, *local_rp;
+	struct mhi_ring *ev_ring = &mhi_event->ring;
+	struct mhi_event_ctxt *er_ctxt =
+		&mhi_cntrl->mhi_ctxt->er_ctxt[mhi_event->er_index];
+	int count = 0;
+	u32 chan;
+	struct mhi_chan *mhi_chan;
+	dma_addr_t ptr = le64_to_cpu(er_ctxt->rp);
+
+	if (unlikely(MHI_EVENT_ACCESS_INVALID(mhi_cntrl->pm_state)))
+		return -EIO;
+
+	if (!is_valid_ring_ptr(ev_ring, ptr)) {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Event ring rp points outside of the event ring\n");
+		return -EIO;
+	}
+
+	dev_rp = mhi_to_virtual(ev_ring, ptr);
+	local_rp = ev_ring->rp;
+
+	while (dev_rp != local_rp && event_quota > 0) {
+		enum mhi_pkt_type type = MHI_TRE_GET_EV_TYPE(local_rp);
+
+		chan = MHI_TRE_GET_EV_CHID(local_rp);
+
+		WARN_ON(chan >= mhi_cntrl->max_chan);
+
+		/*
+		 * Only process the event ring elements whose channel
+		 * ID is within the maximum supported range.
+		 */
+		if (chan < mhi_cntrl->max_chan &&
+		    mhi_cntrl->mhi_chan[chan].configured) {
+			mhi_chan = &mhi_cntrl->mhi_chan[chan];
+
+			if (likely(type == MHI_PKT_TYPE_TX_EVENT)) {
+				parse_xfer_event(mhi_cntrl, local_rp, mhi_chan);
+				event_quota--;
+			} else if (type == MHI_PKT_TYPE_RSC_TX_EVENT) {
+				parse_rsc_event(mhi_cntrl, local_rp, mhi_chan);
+				event_quota--;
+			}
+		}
+
+		mhi_recycle_ev_ring_element(mhi_cntrl, ev_ring);
+		local_rp = ev_ring->rp;
+
+		ptr = le64_to_cpu(er_ctxt->rp);
+		if (!is_valid_ring_ptr(ev_ring, ptr)) {
+			dev_err(&mhi_cntrl->mhi_dev->dev,
+				"Event ring rp points outside of the event ring\n");
+			return -EIO;
+		}
+
+		dev_rp = mhi_to_virtual(ev_ring, ptr);
+		count++;
+	}
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)))
+		mhi_ring_er_db(mhi_event);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	return count;
+}
+
+void mhi_ev_task(unsigned long data)
+{
+	struct mhi_event *mhi_event = (struct mhi_event *)data;
+	struct mhi_controller *mhi_cntrl = mhi_event->mhi_cntrl;
+
+	/* process all pending events */
+	spin_lock_bh(&mhi_event->lock);
+	mhi_event->process_event(mhi_cntrl, mhi_event, U32_MAX);
+	spin_unlock_bh(&mhi_event->lock);
+}
+
+void mhi_ctrl_ev_task(unsigned long data)
+{
+	struct mhi_event *mhi_event = (struct mhi_event *)data;
+	struct mhi_controller *mhi_cntrl = mhi_event->mhi_cntrl;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_state state;
+	enum mhi_pm_state pm_state = 0;
+	int ret;
+
+	/*
+	 * We can check PM state w/o a lock here because there is no way
+	 * PM state can change from reg access valid to no access while this
+	 * thread being executed.
+	 */
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+		/*
+		 * We may have a pending event but not allowed to
+		 * process it since we are probably in a suspended state,
+		 * so trigger a resume.
+		 */
+		mhi_trigger_resume(mhi_cntrl);
+
+		return;
+	}
+
+	/* Process ctrl events */
+	ret = mhi_event->process_event(mhi_cntrl, mhi_event, U32_MAX);
+
+	/*
+	 * We received an IRQ but no events to process, maybe device went to
+	 * SYS_ERR state? Check the state to confirm.
+	 */
+	if (!ret) {
+		write_lock_irq(&mhi_cntrl->pm_lock);
+		state = mhi_get_mhi_state(mhi_cntrl);
+		if (state == MHI_STATE_SYS_ERR) {
+			dev_dbg(dev, "System error detected\n");
+			pm_state = mhi_tryset_pm_state(mhi_cntrl,
+						       MHI_PM_SYS_ERR_DETECT);
+		}
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		if (pm_state == MHI_PM_SYS_ERR_DETECT)
+			mhi_pm_sys_err_handler(mhi_cntrl);
+	}
+}
+
+static bool mhi_is_ring_full(struct mhi_controller *mhi_cntrl,
+			     struct mhi_ring *ring)
+{
+	void *tmp = ring->wp + ring->el_size;
+
+	if (tmp >= (ring->base + ring->len))
+		tmp = ring->base;
+
+	return (tmp == ring->rp);
+}
+
+static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info,
+		     enum dma_data_direction dir, enum mhi_flags mflags)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ? mhi_dev->ul_chan :
+							     mhi_dev->dl_chan;
+	struct mhi_ring *tre_ring = &mhi_chan->tre_ring;
+	unsigned long flags;
+	int ret;
+
+	if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)))
+		return -EIO;
+
+	ret = mhi_is_ring_full(mhi_cntrl, tre_ring);
+	if (unlikely(ret))
+		return -EAGAIN;
+
+	ret = mhi_gen_tre(mhi_cntrl, mhi_chan, buf_info, mflags);
+	if (unlikely(ret))
+		return ret;
+
+	read_lock_irqsave(&mhi_cntrl->pm_lock, flags);
+
+	/* Packet is queued, take a usage ref to exit M3 if necessary
+	 * for host->device buffer, balanced put is done on buffer completion
+	 * for device->host buffer, balanced put is after ringing the DB
+	 */
+	mhi_cntrl->runtime_get(mhi_cntrl);
+
+	/* Assert dev_wake (to exit/prevent M1/M2)*/
+	mhi_cntrl->wake_toggle(mhi_cntrl);
+
+	if (mhi_chan->dir == DMA_TO_DEVICE)
+		atomic_inc(&mhi_cntrl->pending_pkts);
+
+	if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)))
+		mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+
+	if (dir == DMA_FROM_DEVICE)
+		mhi_cntrl->runtime_put(mhi_cntrl);
+
+	read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags);
+
+	return ret;
+}
+
+int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
+		  struct sk_buff *skb, size_t len, enum mhi_flags mflags)
+{
+	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ? mhi_dev->ul_chan :
+							     mhi_dev->dl_chan;
+	struct mhi_buf_info buf_info = { };
+
+	buf_info.v_addr = skb->data;
+	buf_info.cb_buf = skb;
+	buf_info.len = len;
+
+	if (unlikely(mhi_chan->pre_alloc))
+		return -EINVAL;
+
+	return mhi_queue(mhi_dev, &buf_info, dir, mflags);
+}
+EXPORT_SYMBOL_GPL(mhi_queue_skb);
+
+int mhi_queue_dma(struct mhi_device *mhi_dev, enum dma_data_direction dir,
+		  struct mhi_buf *mhi_buf, size_t len, enum mhi_flags mflags)
+{
+	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ? mhi_dev->ul_chan :
+							     mhi_dev->dl_chan;
+	struct mhi_buf_info buf_info = { };
+
+	buf_info.p_addr = mhi_buf->dma_addr;
+	buf_info.cb_buf = mhi_buf;
+	buf_info.pre_mapped = true;
+	buf_info.len = len;
+
+	if (unlikely(mhi_chan->pre_alloc))
+		return -EINVAL;
+
+	return mhi_queue(mhi_dev, &buf_info, dir, mflags);
+}
+EXPORT_SYMBOL_GPL(mhi_queue_dma);
+
+int mhi_gen_tre(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan,
+			struct mhi_buf_info *info, enum mhi_flags flags)
+{
+	struct mhi_ring *buf_ring, *tre_ring;
+	struct mhi_ring_element *mhi_tre;
+	struct mhi_buf_info *buf_info;
+	int eot, eob, chain, bei;
+	int ret;
+
+	/* Protect accesses for reading and incrementing WP */
+	write_lock_bh(&mhi_chan->lock);
+
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+
+	buf_info = buf_ring->wp;
+	WARN_ON(buf_info->used);
+	buf_info->pre_mapped = info->pre_mapped;
+	if (info->pre_mapped)
+		buf_info->p_addr = info->p_addr;
+	else
+		buf_info->v_addr = info->v_addr;
+	buf_info->cb_buf = info->cb_buf;
+	buf_info->wp = tre_ring->wp;
+	buf_info->dir = mhi_chan->dir;
+	buf_info->len = info->len;
+
+	if (!info->pre_mapped) {
+		ret = mhi_cntrl->map_single(mhi_cntrl, buf_info);
+		if (ret) {
+			write_unlock_bh(&mhi_chan->lock);
+			return ret;
+		}
+	}
+
+	eob = !!(flags & MHI_EOB);
+	eot = !!(flags & MHI_EOT);
+	chain = !!(flags & MHI_CHAIN);
+	bei = !!(mhi_chan->intmod);
+
+	mhi_tre = tre_ring->wp;
+	mhi_tre->ptr = MHI_TRE_DATA_PTR(buf_info->p_addr);
+	mhi_tre->dword[0] = MHI_TRE_DATA_DWORD0(info->len);
+	mhi_tre->dword[1] = MHI_TRE_DATA_DWORD1(bei, eot, eob, chain);
+
+	/* increment WP */
+	mhi_add_ring_element(mhi_cntrl, tre_ring);
+	mhi_add_ring_element(mhi_cntrl, buf_ring);
+
+	write_unlock_bh(&mhi_chan->lock);
+
+	return 0;
+}
+
+int mhi_queue_buf(struct mhi_device *mhi_dev, enum dma_data_direction dir,
+		  void *buf, size_t len, enum mhi_flags mflags)
+{
+	struct mhi_buf_info buf_info = { };
+
+	buf_info.v_addr = buf;
+	buf_info.cb_buf = buf;
+	buf_info.len = len;
+
+	return mhi_queue(mhi_dev, &buf_info, dir, mflags);
+}
+EXPORT_SYMBOL_GPL(mhi_queue_buf);
+
+bool mhi_queue_is_full(struct mhi_device *mhi_dev, enum dma_data_direction dir)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ?
+					mhi_dev->ul_chan : mhi_dev->dl_chan;
+	struct mhi_ring *tre_ring = &mhi_chan->tre_ring;
+
+	return mhi_is_ring_full(mhi_cntrl, tre_ring);
+}
+EXPORT_SYMBOL_GPL(mhi_queue_is_full);
+
+int mhi_send_cmd(struct mhi_controller *mhi_cntrl,
+		 struct mhi_chan *mhi_chan,
+		 enum mhi_cmd_type cmd)
+{
+	struct mhi_ring_element *cmd_tre = NULL;
+	struct mhi_cmd *mhi_cmd = &mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING];
+	struct mhi_ring *ring = &mhi_cmd->ring;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int chan = 0;
+
+	if (mhi_chan)
+		chan = mhi_chan->chan;
+
+	spin_lock_bh(&mhi_cmd->lock);
+	if (!get_nr_avail_ring_elements(mhi_cntrl, ring)) {
+		spin_unlock_bh(&mhi_cmd->lock);
+		return -ENOMEM;
+	}
+
+	/* prepare the cmd tre */
+	cmd_tre = ring->wp;
+	switch (cmd) {
+	case MHI_CMD_RESET_CHAN:
+		cmd_tre->ptr = MHI_TRE_CMD_RESET_PTR;
+		cmd_tre->dword[0] = MHI_TRE_CMD_RESET_DWORD0;
+		cmd_tre->dword[1] = MHI_TRE_CMD_RESET_DWORD1(chan);
+		break;
+	case MHI_CMD_STOP_CHAN:
+		cmd_tre->ptr = MHI_TRE_CMD_STOP_PTR;
+		cmd_tre->dword[0] = MHI_TRE_CMD_STOP_DWORD0;
+		cmd_tre->dword[1] = MHI_TRE_CMD_STOP_DWORD1(chan);
+		break;
+	case MHI_CMD_START_CHAN:
+		cmd_tre->ptr = MHI_TRE_CMD_START_PTR;
+		cmd_tre->dword[0] = MHI_TRE_CMD_START_DWORD0;
+		cmd_tre->dword[1] = MHI_TRE_CMD_START_DWORD1(chan);
+		break;
+	default:
+		dev_err(dev, "Command not supported\n");
+		break;
+	}
+
+	/* queue to hardware */
+	mhi_add_ring_element(mhi_cntrl, ring);
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl)))
+		mhi_ring_cmd_db(mhi_cntrl, mhi_cmd);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+	spin_unlock_bh(&mhi_cmd->lock);
+
+	return 0;
+}
+
+static int mhi_update_channel_state(struct mhi_controller *mhi_cntrl,
+				    struct mhi_chan *mhi_chan,
+				    enum mhi_ch_state_type to_state)
+{
+	struct device *dev = &mhi_chan->mhi_dev->dev;
+	enum mhi_cmd_type cmd = MHI_CMD_NOP;
+	int ret;
+
+	dev_dbg(dev, "%d: Updating channel state to: %s\n", mhi_chan->chan,
+		TO_CH_STATE_TYPE_STR(to_state));
+
+	switch (to_state) {
+	case MHI_CH_STATE_TYPE_RESET:
+		write_lock_irq(&mhi_chan->lock);
+		if (mhi_chan->ch_state != MHI_CH_STATE_STOP &&
+		    mhi_chan->ch_state != MHI_CH_STATE_ENABLED &&
+		    mhi_chan->ch_state != MHI_CH_STATE_SUSPENDED) {
+			write_unlock_irq(&mhi_chan->lock);
+			return -EINVAL;
+		}
+		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
+		write_unlock_irq(&mhi_chan->lock);
+
+		cmd = MHI_CMD_RESET_CHAN;
+		break;
+	case MHI_CH_STATE_TYPE_STOP:
+		if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED)
+			return -EINVAL;
+
+		cmd = MHI_CMD_STOP_CHAN;
+		break;
+	case MHI_CH_STATE_TYPE_START:
+		if (mhi_chan->ch_state != MHI_CH_STATE_STOP &&
+		    mhi_chan->ch_state != MHI_CH_STATE_DISABLED)
+			return -EINVAL;
+
+		cmd = MHI_CMD_START_CHAN;
+		break;
+	default:
+		dev_err(dev, "%d: Channel state update to %s not allowed\n",
+			mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state));
+		return -EINVAL;
+	}
+
+	/* bring host and device out of suspended states */
+	ret = mhi_device_get_sync(mhi_cntrl->mhi_dev);
+	if (ret)
+		return ret;
+	mhi_cntrl->runtime_get(mhi_cntrl);
+
+	reinit_completion(&mhi_chan->completion);
+	ret = mhi_send_cmd(mhi_cntrl, mhi_chan, cmd);
+	if (ret) {
+		dev_err(dev, "%d: Failed to send %s channel command\n",
+			mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state));
+		goto exit_channel_update;
+	}
+
+	ret = wait_for_completion_timeout(&mhi_chan->completion,
+				       msecs_to_jiffies(mhi_cntrl->timeout_ms));
+	if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) {
+		dev_err(dev,
+			"%d: Failed to receive %s channel command completion\n",
+			mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state));
+		ret = -EIO;
+		goto exit_channel_update;
+	}
+
+	ret = 0;
+
+	if (to_state != MHI_CH_STATE_TYPE_RESET) {
+		write_lock_irq(&mhi_chan->lock);
+		mhi_chan->ch_state = (to_state == MHI_CH_STATE_TYPE_START) ?
+				      MHI_CH_STATE_ENABLED : MHI_CH_STATE_STOP;
+		write_unlock_irq(&mhi_chan->lock);
+	}
+
+	dev_dbg(dev, "%d: Channel state change to %s successful\n",
+		mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state));
+
+exit_channel_update:
+	mhi_cntrl->runtime_put(mhi_cntrl);
+	mhi_device_put(mhi_cntrl->mhi_dev);
+
+	return ret;
+}
+
+static void mhi_unprepare_channel(struct mhi_controller *mhi_cntrl,
+				  struct mhi_chan *mhi_chan)
+{
+	int ret;
+	struct device *dev = &mhi_chan->mhi_dev->dev;
+
+	mutex_lock(&mhi_chan->mutex);
+
+	if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) {
+		dev_dbg(dev, "Current EE: %s Required EE Mask: 0x%x\n",
+			TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask);
+		goto exit_unprepare_channel;
+	}
+
+	/* no more processing events for this channel */
+	ret = mhi_update_channel_state(mhi_cntrl, mhi_chan,
+				       MHI_CH_STATE_TYPE_RESET);
+	if (ret)
+		dev_err(dev, "%d: Failed to reset channel, still resetting\n",
+			mhi_chan->chan);
+
+exit_unprepare_channel:
+	write_lock_irq(&mhi_chan->lock);
+	mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
+	write_unlock_irq(&mhi_chan->lock);
+
+	if (!mhi_chan->offload_ch) {
+		mhi_reset_chan(mhi_cntrl, mhi_chan);
+		mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
+	}
+	dev_dbg(dev, "%d: successfully reset\n", mhi_chan->chan);
+
+	mutex_unlock(&mhi_chan->mutex);
+}
+
+int mhi_prepare_channel(struct mhi_controller *mhi_cntrl,
+			struct mhi_chan *mhi_chan, unsigned int flags)
+{
+	int ret = 0;
+	struct device *dev = &mhi_chan->mhi_dev->dev;
+
+	if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) {
+		dev_err(dev, "Current EE: %s Required EE Mask: 0x%x\n",
+			TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask);
+		return -ENOTCONN;
+	}
+
+	mutex_lock(&mhi_chan->mutex);
+
+	/* Check of client manages channel context for offload channels */
+	if (!mhi_chan->offload_ch) {
+		ret = mhi_init_chan_ctxt(mhi_cntrl, mhi_chan);
+		if (ret)
+			goto error_init_chan;
+	}
+
+	ret = mhi_update_channel_state(mhi_cntrl, mhi_chan,
+				       MHI_CH_STATE_TYPE_START);
+	if (ret)
+		goto error_pm_state;
+
+	if (mhi_chan->dir == DMA_FROM_DEVICE)
+		mhi_chan->pre_alloc = !!(flags & MHI_CH_INBOUND_ALLOC_BUFS);
+
+	/* Pre-allocate buffer for xfer ring */
+	if (mhi_chan->pre_alloc) {
+		int nr_el = get_nr_avail_ring_elements(mhi_cntrl,
+						       &mhi_chan->tre_ring);
+		size_t len = mhi_cntrl->buffer_len;
+
+		while (nr_el--) {
+			void *buf;
+			struct mhi_buf_info info = { };
+
+			buf = kmalloc(len, GFP_KERNEL);
+			if (!buf) {
+				ret = -ENOMEM;
+				goto error_pre_alloc;
+			}
+
+			/* Prepare transfer descriptors */
+			info.v_addr = buf;
+			info.cb_buf = buf;
+			info.len = len;
+			ret = mhi_gen_tre(mhi_cntrl, mhi_chan, &info, MHI_EOT);
+			if (ret) {
+				kfree(buf);
+				goto error_pre_alloc;
+			}
+		}
+
+		read_lock_bh(&mhi_cntrl->pm_lock);
+		if (MHI_DB_ACCESS_VALID(mhi_cntrl)) {
+			read_lock_irq(&mhi_chan->lock);
+			mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+			read_unlock_irq(&mhi_chan->lock);
+		}
+		read_unlock_bh(&mhi_cntrl->pm_lock);
+	}
+
+	mutex_unlock(&mhi_chan->mutex);
+
+	return 0;
+
+error_pm_state:
+	if (!mhi_chan->offload_ch)
+		mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
+
+error_init_chan:
+	mutex_unlock(&mhi_chan->mutex);
+
+	return ret;
+
+error_pre_alloc:
+	mutex_unlock(&mhi_chan->mutex);
+	mhi_unprepare_channel(mhi_cntrl, mhi_chan);
+
+	return ret;
+}
+
+static void mhi_mark_stale_events(struct mhi_controller *mhi_cntrl,
+				  struct mhi_event *mhi_event,
+				  struct mhi_event_ctxt *er_ctxt,
+				  int chan)
+
+{
+	struct mhi_ring_element *dev_rp, *local_rp;
+	struct mhi_ring *ev_ring;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	unsigned long flags;
+	dma_addr_t ptr;
+
+	dev_dbg(dev, "Marking all events for chan: %d as stale\n", chan);
+
+	ev_ring = &mhi_event->ring;
+
+	/* mark all stale events related to channel as STALE event */
+	spin_lock_irqsave(&mhi_event->lock, flags);
+
+	ptr = le64_to_cpu(er_ctxt->rp);
+	if (!is_valid_ring_ptr(ev_ring, ptr)) {
+		dev_err(&mhi_cntrl->mhi_dev->dev,
+			"Event ring rp points outside of the event ring\n");
+		dev_rp = ev_ring->rp;
+	} else {
+		dev_rp = mhi_to_virtual(ev_ring, ptr);
+	}
+
+	local_rp = ev_ring->rp;
+	while (dev_rp != local_rp) {
+		if (MHI_TRE_GET_EV_TYPE(local_rp) == MHI_PKT_TYPE_TX_EVENT &&
+		    chan == MHI_TRE_GET_EV_CHID(local_rp))
+			local_rp->dword[1] = MHI_TRE_EV_DWORD1(chan,
+					MHI_PKT_TYPE_STALE_EVENT);
+		local_rp++;
+		if (local_rp == (ev_ring->base + ev_ring->len))
+			local_rp = ev_ring->base;
+	}
+
+	dev_dbg(dev, "Finished marking events as stale events\n");
+	spin_unlock_irqrestore(&mhi_event->lock, flags);
+}
+
+static void mhi_reset_data_chan(struct mhi_controller *mhi_cntrl,
+				struct mhi_chan *mhi_chan)
+{
+	struct mhi_ring *buf_ring, *tre_ring;
+	struct mhi_result result;
+
+	/* Reset any pending buffers */
+	buf_ring = &mhi_chan->buf_ring;
+	tre_ring = &mhi_chan->tre_ring;
+	result.transaction_status = -ENOTCONN;
+	result.bytes_xferd = 0;
+	while (tre_ring->rp != tre_ring->wp) {
+		struct mhi_buf_info *buf_info = buf_ring->rp;
+
+		if (mhi_chan->dir == DMA_TO_DEVICE) {
+			atomic_dec(&mhi_cntrl->pending_pkts);
+			/* Release the reference got from mhi_queue() */
+			mhi_cntrl->runtime_put(mhi_cntrl);
+		}
+
+		if (!buf_info->pre_mapped)
+			mhi_cntrl->unmap_single(mhi_cntrl, buf_info);
+
+		mhi_del_ring_element(mhi_cntrl, buf_ring);
+		mhi_del_ring_element(mhi_cntrl, tre_ring);
+
+		if (mhi_chan->pre_alloc) {
+			kfree(buf_info->cb_buf);
+		} else {
+			result.buf_addr = buf_info->cb_buf;
+			mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
+		}
+	}
+}
+
+void mhi_reset_chan(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan)
+{
+	struct mhi_event *mhi_event;
+	struct mhi_event_ctxt *er_ctxt;
+	int chan = mhi_chan->chan;
+
+	/* Nothing to reset, client doesn't queue buffers */
+	if (mhi_chan->offload_ch)
+		return;
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index];
+	er_ctxt = &mhi_cntrl->mhi_ctxt->er_ctxt[mhi_chan->er_index];
+
+	mhi_mark_stale_events(mhi_cntrl, mhi_event, er_ctxt, chan);
+
+	mhi_reset_data_chan(mhi_cntrl, mhi_chan);
+
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+}
+
+static int __mhi_prepare_for_transfer(struct mhi_device *mhi_dev, unsigned int flags)
+{
+	int ret, dir;
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan;
+
+	for (dir = 0; dir < 2; dir++) {
+		mhi_chan = dir ? mhi_dev->dl_chan : mhi_dev->ul_chan;
+		if (!mhi_chan)
+			continue;
+
+		ret = mhi_prepare_channel(mhi_cntrl, mhi_chan, flags);
+		if (ret)
+			goto error_open_chan;
+	}
+
+	return 0;
+
+error_open_chan:
+	for (--dir; dir >= 0; dir--) {
+		mhi_chan = dir ? mhi_dev->dl_chan : mhi_dev->ul_chan;
+		if (!mhi_chan)
+			continue;
+
+		mhi_unprepare_channel(mhi_cntrl, mhi_chan);
+	}
+
+	return ret;
+}
+
+int mhi_prepare_for_transfer(struct mhi_device *mhi_dev)
+{
+	return __mhi_prepare_for_transfer(mhi_dev, 0);
+}
+EXPORT_SYMBOL_GPL(mhi_prepare_for_transfer);
+
+int mhi_prepare_for_transfer_autoqueue(struct mhi_device *mhi_dev)
+{
+	return __mhi_prepare_for_transfer(mhi_dev, MHI_CH_INBOUND_ALLOC_BUFS);
+}
+EXPORT_SYMBOL_GPL(mhi_prepare_for_transfer_autoqueue);
+
+void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan;
+	int dir;
+
+	for (dir = 0; dir < 2; dir++) {
+		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
+		if (!mhi_chan)
+			continue;
+
+		mhi_unprepare_channel(mhi_cntrl, mhi_chan);
+	}
+}
+EXPORT_SYMBOL_GPL(mhi_unprepare_from_transfer);
+
+int mhi_poll(struct mhi_device *mhi_dev, u32 budget)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_chan *mhi_chan = mhi_dev->dl_chan;
+	struct mhi_event *mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index];
+	int ret;
+
+	spin_lock_bh(&mhi_event->lock);
+	ret = mhi_event->process_event(mhi_cntrl, mhi_event, budget);
+	spin_unlock_bh(&mhi_event->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_poll);
diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
new file mode 100644
index 000000000..caa4ce28c
--- /dev/null
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -0,0 +1,1226 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MHI PCI driver - MHI over PCI controller driver
+ *
+ * This module is a generic driver for registering MHI-over-PCI devices,
+ * such as PCIe QCOM modems.
+ *
+ * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org>
+ */
+
+#include <linux/aer.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pm_runtime.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+#define MHI_PCI_DEFAULT_BAR_NUM 0
+
+#define MHI_POST_RESET_DELAY_MS 2000
+
+#define HEALTH_CHECK_PERIOD (HZ * 2)
+
+/**
+ * struct mhi_pci_dev_info - MHI PCI device specific information
+ * @config: MHI controller configuration
+ * @name: name of the PCI module
+ * @fw: firmware path (if any)
+ * @edl: emergency download mode firmware path (if any)
+ * @bar_num: PCI base address register to use for MHI MMIO register space
+ * @dma_data_width: DMA transfer word size (32 or 64 bits)
+ * @mru_default: default MRU size for MBIM network packets
+ * @sideband_wake: Devices using dedicated sideband GPIO for wakeup instead
+ *		   of inband wake support (such as sdx24)
+ */
+struct mhi_pci_dev_info {
+	const struct mhi_controller_config *config;
+	const char *name;
+	const char *fw;
+	const char *edl;
+	unsigned int bar_num;
+	unsigned int dma_data_width;
+	unsigned int mru_default;
+	bool sideband_wake;
+};
+
+#define MHI_CHANNEL_CONFIG_UL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_TO_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}						\
+
+#define MHI_CHANNEL_CONFIG_DL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}
+
+#define MHI_CHANNEL_CONFIG_DL_AUTOQUEUE(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+		.auto_queue = true,			\
+	}
+
+#define MHI_EVENT_CONFIG_CTRL(ev_ring, el_count) \
+	{					\
+		.num_elements = el_count,	\
+		.irq_moderation_ms = 0,		\
+		.irq = (ev_ring) + 1,		\
+		.priority = 1,			\
+		.mode = MHI_DB_BRST_DISABLE,	\
+		.data_type = MHI_ER_CTRL,	\
+		.hardware_event = false,	\
+		.client_managed = false,	\
+		.offload_channel = false,	\
+	}
+
+#define MHI_CHANNEL_CONFIG_HW_UL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_TO_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_ENABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = true,		\
+	}						\
+
+#define MHI_CHANNEL_CONFIG_HW_DL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_AMSS),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_ENABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = true,		\
+	}
+
+#define MHI_CHANNEL_CONFIG_UL_SBL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_TO_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_SBL),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}						\
+
+#define MHI_CHANNEL_CONFIG_DL_SBL(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_SBL),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}
+
+#define MHI_CHANNEL_CONFIG_UL_FP(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_TO_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_FP),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}						\
+
+#define MHI_CHANNEL_CONFIG_DL_FP(ch_num, ch_name, el_count, ev_ring) \
+	{						\
+		.num = ch_num,				\
+		.name = ch_name,			\
+		.num_elements = el_count,		\
+		.event_ring = ev_ring,			\
+		.dir = DMA_FROM_DEVICE,			\
+		.ee_mask = BIT(MHI_EE_FP),		\
+		.pollcfg = 0,				\
+		.doorbell = MHI_DB_BRST_DISABLE,	\
+		.lpm_notify = false,			\
+		.offload_channel = false,		\
+		.doorbell_mode_switch = false,		\
+	}
+
+#define MHI_EVENT_CONFIG_DATA(ev_ring, el_count) \
+	{					\
+		.num_elements = el_count,	\
+		.irq_moderation_ms = 5,		\
+		.irq = (ev_ring) + 1,		\
+		.priority = 1,			\
+		.mode = MHI_DB_BRST_DISABLE,	\
+		.data_type = MHI_ER_DATA,	\
+		.hardware_event = false,	\
+		.client_managed = false,	\
+		.offload_channel = false,	\
+	}
+
+#define MHI_EVENT_CONFIG_HW_DATA(ev_ring, el_count, ch_num) \
+	{					\
+		.num_elements = el_count,	\
+		.irq_moderation_ms = 1,		\
+		.irq = (ev_ring) + 1,		\
+		.priority = 1,			\
+		.mode = MHI_DB_BRST_DISABLE,	\
+		.data_type = MHI_ER_DATA,	\
+		.hardware_event = true,		\
+		.client_managed = false,	\
+		.offload_channel = false,	\
+		.channel = ch_num,		\
+	}
+
+static const struct mhi_channel_config modem_qcom_v1_mhi_channels[] = {
+	MHI_CHANNEL_CONFIG_UL(4, "DIAG", 16, 1),
+	MHI_CHANNEL_CONFIG_DL(5, "DIAG", 16, 1),
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 4, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 4, 0),
+	MHI_CHANNEL_CONFIG_UL(14, "QMI", 4, 0),
+	MHI_CHANNEL_CONFIG_DL(15, "QMI", 4, 0),
+	MHI_CHANNEL_CONFIG_UL(20, "IPCR", 8, 0),
+	MHI_CHANNEL_CONFIG_DL_AUTOQUEUE(21, "IPCR", 8, 0),
+	MHI_CHANNEL_CONFIG_UL_FP(34, "FIREHOSE", 32, 0),
+	MHI_CHANNEL_CONFIG_DL_FP(35, "FIREHOSE", 32, 0),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0", 128, 2),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0", 128, 3),
+};
+
+static struct mhi_event_config modem_qcom_v1_mhi_events[] = {
+	/* first ring is control+data ring */
+	MHI_EVENT_CONFIG_CTRL(0, 64),
+	/* DIAG dedicated event ring */
+	MHI_EVENT_CONFIG_DATA(1, 128),
+	/* Hardware channels request dedicated hardware event rings */
+	MHI_EVENT_CONFIG_HW_DATA(2, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(3, 2048, 101)
+};
+
+static const struct mhi_controller_config modem_qcom_v1_mhiv_config = {
+	.max_channels = 128,
+	.timeout_ms = 8000,
+	.num_channels = ARRAY_SIZE(modem_qcom_v1_mhi_channels),
+	.ch_cfg = modem_qcom_v1_mhi_channels,
+	.num_events = ARRAY_SIZE(modem_qcom_v1_mhi_events),
+	.event_cfg = modem_qcom_v1_mhi_events,
+};
+
+static const struct mhi_pci_dev_info mhi_qcom_sdx65_info = {
+	.name = "qcom-sdx65m",
+	.fw = "qcom/sdx65m/xbl.elf",
+	.edl = "qcom/sdx65m/edl.mbn",
+	.config = &modem_qcom_v1_mhiv_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.sideband_wake = false,
+};
+
+static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
+	.name = "qcom-sdx55m",
+	.fw = "qcom/sdx55m/sbl1.mbn",
+	.edl = "qcom/sdx55m/edl.mbn",
+	.config = &modem_qcom_v1_mhiv_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+	.sideband_wake = false,
+};
+
+static const struct mhi_pci_dev_info mhi_qcom_sdx24_info = {
+	.name = "qcom-sdx24",
+	.edl = "qcom/prog_firehose_sdx24.mbn",
+	.config = &modem_qcom_v1_mhiv_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.sideband_wake = true,
+};
+
+static const struct mhi_channel_config mhi_quectel_em1xx_channels[] = {
+	MHI_CHANNEL_CONFIG_UL(0, "NMEA", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(1, "NMEA", 32, 0),
+	MHI_CHANNEL_CONFIG_UL_SBL(2, "SAHARA", 32, 0),
+	MHI_CHANNEL_CONFIG_DL_SBL(3, "SAHARA", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(4, "DIAG", 32, 1),
+	MHI_CHANNEL_CONFIG_DL(5, "DIAG", 32, 1),
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(32, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(33, "DUN", 32, 0),
+	/* The EDL firmware is a flash-programmer exposing firehose protocol */
+	MHI_CHANNEL_CONFIG_UL_FP(34, "FIREHOSE", 32, 0),
+	MHI_CHANNEL_CONFIG_DL_FP(35, "FIREHOSE", 32, 0),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0_MBIM", 128, 2),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0_MBIM", 128, 3),
+};
+
+static struct mhi_event_config mhi_quectel_em1xx_events[] = {
+	MHI_EVENT_CONFIG_CTRL(0, 128),
+	MHI_EVENT_CONFIG_DATA(1, 128),
+	MHI_EVENT_CONFIG_HW_DATA(2, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(3, 1024, 101)
+};
+
+static const struct mhi_controller_config modem_quectel_em1xx_config = {
+	.max_channels = 128,
+	.timeout_ms = 20000,
+	.num_channels = ARRAY_SIZE(mhi_quectel_em1xx_channels),
+	.ch_cfg = mhi_quectel_em1xx_channels,
+	.num_events = ARRAY_SIZE(mhi_quectel_em1xx_events),
+	.event_cfg = mhi_quectel_em1xx_events,
+};
+
+static const struct mhi_pci_dev_info mhi_quectel_em1xx_info = {
+	.name = "quectel-em1xx",
+	.edl = "qcom/prog_firehose_sdx24.mbn",
+	.config = &modem_quectel_em1xx_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+	.sideband_wake = true,
+};
+
+static const struct mhi_channel_config mhi_foxconn_sdx55_channels[] = {
+	MHI_CHANNEL_CONFIG_UL(0, "LOOPBACK", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(1, "LOOPBACK", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(4, "DIAG", 32, 1),
+	MHI_CHANNEL_CONFIG_DL(5, "DIAG", 32, 1),
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(32, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(33, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0_MBIM", 128, 2),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0_MBIM", 128, 3),
+};
+
+static struct mhi_event_config mhi_foxconn_sdx55_events[] = {
+	MHI_EVENT_CONFIG_CTRL(0, 128),
+	MHI_EVENT_CONFIG_DATA(1, 128),
+	MHI_EVENT_CONFIG_HW_DATA(2, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(3, 1024, 101)
+};
+
+static const struct mhi_controller_config modem_foxconn_sdx55_config = {
+	.max_channels = 128,
+	.timeout_ms = 20000,
+	.num_channels = ARRAY_SIZE(mhi_foxconn_sdx55_channels),
+	.ch_cfg = mhi_foxconn_sdx55_channels,
+	.num_events = ARRAY_SIZE(mhi_foxconn_sdx55_events),
+	.event_cfg = mhi_foxconn_sdx55_events,
+};
+
+static const struct mhi_pci_dev_info mhi_foxconn_sdx55_info = {
+	.name = "foxconn-sdx55",
+	.fw = "qcom/sdx55m/sbl1.mbn",
+	.edl = "qcom/sdx55m/edl.mbn",
+	.config = &modem_foxconn_sdx55_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+	.sideband_wake = false,
+};
+
+static const struct mhi_pci_dev_info mhi_foxconn_sdx65_info = {
+	.name = "foxconn-sdx65",
+	.config = &modem_foxconn_sdx55_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+	.sideband_wake = false,
+};
+
+static const struct mhi_channel_config mhi_mv3x_channels[] = {
+	MHI_CHANNEL_CONFIG_UL(0, "LOOPBACK", 64, 0),
+	MHI_CHANNEL_CONFIG_DL(1, "LOOPBACK", 64, 0),
+	/* MBIM Control Channel */
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 64, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 64, 0),
+	/* MBIM Data Channel */
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0_MBIM", 512, 2),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0_MBIM", 512, 3),
+};
+
+static struct mhi_event_config mhi_mv3x_events[] = {
+	MHI_EVENT_CONFIG_CTRL(0, 256),
+	MHI_EVENT_CONFIG_DATA(1, 256),
+	MHI_EVENT_CONFIG_HW_DATA(2, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(3, 1024, 101),
+};
+
+static const struct mhi_controller_config modem_mv3x_config = {
+	.max_channels = 128,
+	.timeout_ms = 20000,
+	.num_channels = ARRAY_SIZE(mhi_mv3x_channels),
+	.ch_cfg = mhi_mv3x_channels,
+	.num_events = ARRAY_SIZE(mhi_mv3x_events),
+	.event_cfg = mhi_mv3x_events,
+};
+
+static const struct mhi_pci_dev_info mhi_mv31_info = {
+	.name = "cinterion-mv31",
+	.config = &modem_mv3x_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+};
+
+static const struct mhi_pci_dev_info mhi_mv32_info = {
+	.name = "cinterion-mv32",
+	.config = &modem_mv3x_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+};
+
+static const struct mhi_channel_config mhi_sierra_em919x_channels[] = {
+	MHI_CHANNEL_CONFIG_UL_SBL(2, "SAHARA", 32, 0),
+	MHI_CHANNEL_CONFIG_DL_SBL(3, "SAHARA", 256, 0),
+	MHI_CHANNEL_CONFIG_UL(4, "DIAG", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(5, "DIAG", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 128, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 128, 0),
+	MHI_CHANNEL_CONFIG_UL(14, "QMI", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(15, "QMI", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(32, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(33, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0", 512, 1),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0", 512, 2),
+};
+
+static struct mhi_event_config modem_sierra_em919x_mhi_events[] = {
+	/* first ring is control+data and DIAG ring */
+	MHI_EVENT_CONFIG_CTRL(0, 2048),
+	/* Hardware channels request dedicated hardware event rings */
+	MHI_EVENT_CONFIG_HW_DATA(1, 2048, 100),
+	MHI_EVENT_CONFIG_HW_DATA(2, 2048, 101)
+};
+
+static const struct mhi_controller_config modem_sierra_em919x_config = {
+	.max_channels = 128,
+	.timeout_ms = 24000,
+	.num_channels = ARRAY_SIZE(mhi_sierra_em919x_channels),
+	.ch_cfg = mhi_sierra_em919x_channels,
+	.num_events = ARRAY_SIZE(modem_sierra_em919x_mhi_events),
+	.event_cfg = modem_sierra_em919x_mhi_events,
+};
+
+static const struct mhi_pci_dev_info mhi_sierra_em919x_info = {
+	.name = "sierra-em919x",
+	.config = &modem_sierra_em919x_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.sideband_wake = false,
+};
+
+static const struct mhi_channel_config mhi_telit_fn980_hw_v1_channels[] = {
+	MHI_CHANNEL_CONFIG_UL(14, "QMI", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(15, "QMI", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(20, "IPCR", 16, 0),
+	MHI_CHANNEL_CONFIG_DL_AUTOQUEUE(21, "IPCR", 16, 0),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0", 128, 1),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0", 128, 2),
+};
+
+static struct mhi_event_config mhi_telit_fn980_hw_v1_events[] = {
+	MHI_EVENT_CONFIG_CTRL(0, 128),
+	MHI_EVENT_CONFIG_HW_DATA(1, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(2, 2048, 101)
+};
+
+static struct mhi_controller_config modem_telit_fn980_hw_v1_config = {
+	.max_channels = 128,
+	.timeout_ms = 20000,
+	.num_channels = ARRAY_SIZE(mhi_telit_fn980_hw_v1_channels),
+	.ch_cfg = mhi_telit_fn980_hw_v1_channels,
+	.num_events = ARRAY_SIZE(mhi_telit_fn980_hw_v1_events),
+	.event_cfg = mhi_telit_fn980_hw_v1_events,
+};
+
+static const struct mhi_pci_dev_info mhi_telit_fn980_hw_v1_info = {
+	.name = "telit-fn980-hwv1",
+	.fw = "qcom/sdx55m/sbl1.mbn",
+	.edl = "qcom/sdx55m/edl.mbn",
+	.config = &modem_telit_fn980_hw_v1_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.mru_default = 32768,
+	.sideband_wake = false,
+};
+
+static const struct mhi_channel_config mhi_telit_fn990_channels[] = {
+	MHI_CHANNEL_CONFIG_UL_SBL(2, "SAHARA", 32, 0),
+	MHI_CHANNEL_CONFIG_DL_SBL(3, "SAHARA", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(4, "DIAG", 64, 1),
+	MHI_CHANNEL_CONFIG_DL(5, "DIAG", 64, 1),
+	MHI_CHANNEL_CONFIG_UL(12, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(13, "MBIM", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(32, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_DL(33, "DUN", 32, 0),
+	MHI_CHANNEL_CONFIG_UL(92, "DUN2", 32, 1),
+	MHI_CHANNEL_CONFIG_DL(93, "DUN2", 32, 1),
+	MHI_CHANNEL_CONFIG_HW_UL(100, "IP_HW0_MBIM", 128, 2),
+	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0_MBIM", 128, 3),
+};
+
+static struct mhi_event_config mhi_telit_fn990_events[] = {
+	MHI_EVENT_CONFIG_CTRL(0, 128),
+	MHI_EVENT_CONFIG_DATA(1, 128),
+	MHI_EVENT_CONFIG_HW_DATA(2, 1024, 100),
+	MHI_EVENT_CONFIG_HW_DATA(3, 2048, 101)
+};
+
+static const struct mhi_controller_config modem_telit_fn990_config = {
+	.max_channels = 128,
+	.timeout_ms = 20000,
+	.num_channels = ARRAY_SIZE(mhi_telit_fn990_channels),
+	.ch_cfg = mhi_telit_fn990_channels,
+	.num_events = ARRAY_SIZE(mhi_telit_fn990_events),
+	.event_cfg = mhi_telit_fn990_events,
+};
+
+static const struct mhi_pci_dev_info mhi_telit_fn990_info = {
+	.name = "telit-fn990",
+	.config = &modem_telit_fn990_config,
+	.bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+	.dma_data_width = 32,
+	.sideband_wake = false,
+	.mru_default = 32768,
+};
+
+/* Keep the list sorted based on the PID. New VID should be added as the last entry */
+static const struct pci_device_id mhi_pci_id_table[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_QCOM, 0x0304),
+		.driver_data = (kernel_ulong_t) &mhi_qcom_sdx24_info },
+	/* EM919x (sdx55), use the same vid:pid as qcom-sdx55m */
+	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_QCOM, 0x0306, 0x18d7, 0x0200),
+		.driver_data = (kernel_ulong_t) &mhi_sierra_em919x_info },
+	/* Telit FN980 hardware revision v1 */
+	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_QCOM, 0x0306, 0x1C5D, 0x2000),
+		.driver_data = (kernel_ulong_t) &mhi_telit_fn980_hw_v1_info },
+	{ PCI_DEVICE(PCI_VENDOR_ID_QCOM, 0x0306),
+		.driver_data = (kernel_ulong_t) &mhi_qcom_sdx55_info },
+	/* Telit FN990 */
+	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_QCOM, 0x0308, 0x1c5d, 0x2010),
+		.driver_data = (kernel_ulong_t) &mhi_telit_fn990_info },
+	{ PCI_DEVICE(PCI_VENDOR_ID_QCOM, 0x0308),
+		.driver_data = (kernel_ulong_t) &mhi_qcom_sdx65_info },
+	{ PCI_DEVICE(0x1eac, 0x1001), /* EM120R-GL (sdx24) */
+		.driver_data = (kernel_ulong_t) &mhi_quectel_em1xx_info },
+	{ PCI_DEVICE(0x1eac, 0x1002), /* EM160R-GL (sdx24) */
+		.driver_data = (kernel_ulong_t) &mhi_quectel_em1xx_info },
+	{ PCI_DEVICE(0x1eac, 0x2001), /* EM120R-GL for FCCL (sdx24) */
+		.driver_data = (kernel_ulong_t) &mhi_quectel_em1xx_info },
+	/* T99W175 (sdx55), Both for eSIM and Non-eSIM */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0ab),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx55_info },
+	/* DW5930e (sdx55), With eSIM, It's also T99W175 */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0b0),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx55_info },
+	/* DW5930e (sdx55), Non-eSIM, It's also T99W175 */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0b1),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx55_info },
+	/* T99W175 (sdx55), Based on Qualcomm new baseline */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0bf),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx55_info },
+	/* T99W175 (sdx55) */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0c3),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx55_info },
+	/* T99W368 (sdx65) */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0d8),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx65_info },
+	/* T99W373 (sdx62) */
+	{ PCI_DEVICE(PCI_VENDOR_ID_FOXCONN, 0xe0d9),
+		.driver_data = (kernel_ulong_t) &mhi_foxconn_sdx65_info },
+	/* MV31-W (Cinterion) */
+	{ PCI_DEVICE(0x1269, 0x00b3),
+		.driver_data = (kernel_ulong_t) &mhi_mv31_info },
+	/* MV31-W (Cinterion), based on new baseline */
+	{ PCI_DEVICE(0x1269, 0x00b4),
+		.driver_data = (kernel_ulong_t) &mhi_mv31_info },
+	/* MV32-WA (Cinterion) */
+	{ PCI_DEVICE(0x1269, 0x00ba),
+		.driver_data = (kernel_ulong_t) &mhi_mv32_info },
+	/* MV32-WB (Cinterion) */
+	{ PCI_DEVICE(0x1269, 0x00bb),
+		.driver_data = (kernel_ulong_t) &mhi_mv32_info },
+	{  }
+};
+MODULE_DEVICE_TABLE(pci, mhi_pci_id_table);
+
+enum mhi_pci_device_status {
+	MHI_PCI_DEV_STARTED,
+	MHI_PCI_DEV_SUSPENDED,
+};
+
+struct mhi_pci_device {
+	struct mhi_controller mhi_cntrl;
+	struct pci_saved_state *pci_state;
+	struct work_struct recovery_work;
+	struct timer_list health_check_timer;
+	unsigned long status;
+};
+
+static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl,
+			    void __iomem *addr, u32 *out)
+{
+	*out = readl(addr);
+	return 0;
+}
+
+static void mhi_pci_write_reg(struct mhi_controller *mhi_cntrl,
+			      void __iomem *addr, u32 val)
+{
+	writel(val, addr);
+}
+
+static void mhi_pci_status_cb(struct mhi_controller *mhi_cntrl,
+			      enum mhi_callback cb)
+{
+	struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+
+	/* Nothing to do for now */
+	switch (cb) {
+	case MHI_CB_FATAL_ERROR:
+	case MHI_CB_SYS_ERROR:
+		dev_warn(&pdev->dev, "firmware crashed (%u)\n", cb);
+		pm_runtime_forbid(&pdev->dev);
+		break;
+	case MHI_CB_EE_MISSION_MODE:
+		pm_runtime_allow(&pdev->dev);
+		break;
+	default:
+		break;
+	}
+}
+
+static void mhi_pci_wake_get_nop(struct mhi_controller *mhi_cntrl, bool force)
+{
+	/* no-op */
+}
+
+static void mhi_pci_wake_put_nop(struct mhi_controller *mhi_cntrl, bool override)
+{
+	/* no-op */
+}
+
+static void mhi_pci_wake_toggle_nop(struct mhi_controller *mhi_cntrl)
+{
+	/* no-op */
+}
+
+static bool mhi_pci_is_alive(struct mhi_controller *mhi_cntrl)
+{
+	struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+	u16 vendor = 0;
+
+	if (pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor))
+		return false;
+
+	if (vendor == (u16) ~0 || vendor == 0)
+		return false;
+
+	return true;
+}
+
+static int mhi_pci_claim(struct mhi_controller *mhi_cntrl,
+			 unsigned int bar_num, u64 dma_mask)
+{
+	struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+	int err;
+
+	err = pci_assign_resource(pdev, bar_num);
+	if (err)
+		return err;
+
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable pci device: %d\n", err);
+		return err;
+	}
+
+	err = pcim_iomap_regions(pdev, 1 << bar_num, pci_name(pdev));
+	if (err) {
+		dev_err(&pdev->dev, "failed to map pci region: %d\n", err);
+		return err;
+	}
+	mhi_cntrl->regs = pcim_iomap_table(pdev)[bar_num];
+	mhi_cntrl->reg_len = pci_resource_len(pdev, bar_num);
+
+	err = dma_set_mask_and_coherent(&pdev->dev, dma_mask);
+	if (err) {
+		dev_err(&pdev->dev, "Cannot set proper DMA mask\n");
+		return err;
+	}
+
+	pci_set_master(pdev);
+
+	return 0;
+}
+
+static int mhi_pci_get_irqs(struct mhi_controller *mhi_cntrl,
+			    const struct mhi_controller_config *mhi_cntrl_config)
+{
+	struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+	int nr_vectors, i;
+	int *irq;
+
+	/*
+	 * Alloc one MSI vector for BHI + one vector per event ring, ideally...
+	 * No explicit pci_free_irq_vectors required, done by pcim_release.
+	 */
+	mhi_cntrl->nr_irqs = 1 + mhi_cntrl_config->num_events;
+
+	nr_vectors = pci_alloc_irq_vectors(pdev, 1, mhi_cntrl->nr_irqs, PCI_IRQ_MSI);
+	if (nr_vectors < 0) {
+		dev_err(&pdev->dev, "Error allocating MSI vectors %d\n",
+			nr_vectors);
+		return nr_vectors;
+	}
+
+	if (nr_vectors < mhi_cntrl->nr_irqs) {
+		dev_warn(&pdev->dev, "using shared MSI\n");
+
+		/* Patch msi vectors, use only one (shared) */
+		for (i = 0; i < mhi_cntrl_config->num_events; i++)
+			mhi_cntrl_config->event_cfg[i].irq = 0;
+		mhi_cntrl->nr_irqs = 1;
+	}
+
+	irq = devm_kcalloc(&pdev->dev, mhi_cntrl->nr_irqs, sizeof(int), GFP_KERNEL);
+	if (!irq)
+		return -ENOMEM;
+
+	for (i = 0; i < mhi_cntrl->nr_irqs; i++) {
+		int vector = i >= nr_vectors ? (nr_vectors - 1) : i;
+
+		irq[i] = pci_irq_vector(pdev, vector);
+	}
+
+	mhi_cntrl->irq = irq;
+
+	return 0;
+}
+
+static int mhi_pci_runtime_get(struct mhi_controller *mhi_cntrl)
+{
+	/* The runtime_get() MHI callback means:
+	 *    Do whatever is requested to leave M3.
+	 */
+	return pm_runtime_get(mhi_cntrl->cntrl_dev);
+}
+
+static void mhi_pci_runtime_put(struct mhi_controller *mhi_cntrl)
+{
+	/* The runtime_put() MHI callback means:
+	 *    Device can be moved in M3 state.
+	 */
+	pm_runtime_mark_last_busy(mhi_cntrl->cntrl_dev);
+	pm_runtime_put(mhi_cntrl->cntrl_dev);
+}
+
+static void mhi_pci_recovery_work(struct work_struct *work)
+{
+	struct mhi_pci_device *mhi_pdev = container_of(work, struct mhi_pci_device,
+						       recovery_work);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+	struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+	int err;
+
+	dev_warn(&pdev->dev, "device recovery started\n");
+
+	del_timer(&mhi_pdev->health_check_timer);
+	pm_runtime_forbid(&pdev->dev);
+
+	/* Clean up MHI state */
+	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
+		mhi_power_down(mhi_cntrl, false);
+		mhi_unprepare_after_power_down(mhi_cntrl);
+	}
+
+	pci_set_power_state(pdev, PCI_D0);
+	pci_load_saved_state(pdev, mhi_pdev->pci_state);
+	pci_restore_state(pdev);
+
+	if (!mhi_pci_is_alive(mhi_cntrl))
+		goto err_try_reset;
+
+	err = mhi_prepare_for_power_up(mhi_cntrl);
+	if (err)
+		goto err_try_reset;
+
+	err = mhi_sync_power_up(mhi_cntrl);
+	if (err)
+		goto err_unprepare;
+
+	dev_dbg(&pdev->dev, "Recovery completed\n");
+
+	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
+	mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
+	return;
+
+err_unprepare:
+	mhi_unprepare_after_power_down(mhi_cntrl);
+err_try_reset:
+	if (pci_reset_function(pdev))
+		dev_err(&pdev->dev, "Recovery failed\n");
+}
+
+static void health_check(struct timer_list *t)
+{
+	struct mhi_pci_device *mhi_pdev = from_timer(mhi_pdev, t, health_check_timer);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	if (!test_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status) ||
+			test_bit(MHI_PCI_DEV_SUSPENDED, &mhi_pdev->status))
+		return;
+
+	if (!mhi_pci_is_alive(mhi_cntrl)) {
+		dev_err(mhi_cntrl->cntrl_dev, "Device died\n");
+		queue_work(system_long_wq, &mhi_pdev->recovery_work);
+		return;
+	}
+
+	/* reschedule in two seconds */
+	mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
+}
+
+static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info *) id->driver_data;
+	const struct mhi_controller_config *mhi_cntrl_config;
+	struct mhi_pci_device *mhi_pdev;
+	struct mhi_controller *mhi_cntrl;
+	int err;
+
+	dev_info(&pdev->dev, "MHI PCI device found: %s\n", info->name);
+
+	/* mhi_pdev.mhi_cntrl must be zero-initialized */
+	mhi_pdev = devm_kzalloc(&pdev->dev, sizeof(*mhi_pdev), GFP_KERNEL);
+	if (!mhi_pdev)
+		return -ENOMEM;
+
+	INIT_WORK(&mhi_pdev->recovery_work, mhi_pci_recovery_work);
+	timer_setup(&mhi_pdev->health_check_timer, health_check, 0);
+
+	mhi_cntrl_config = info->config;
+	mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	mhi_cntrl->cntrl_dev = &pdev->dev;
+	mhi_cntrl->iova_start = 0;
+	mhi_cntrl->iova_stop = (dma_addr_t)DMA_BIT_MASK(info->dma_data_width);
+	mhi_cntrl->fw_image = info->fw;
+	mhi_cntrl->edl_image = info->edl;
+
+	mhi_cntrl->read_reg = mhi_pci_read_reg;
+	mhi_cntrl->write_reg = mhi_pci_write_reg;
+	mhi_cntrl->status_cb = mhi_pci_status_cb;
+	mhi_cntrl->runtime_get = mhi_pci_runtime_get;
+	mhi_cntrl->runtime_put = mhi_pci_runtime_put;
+	mhi_cntrl->mru = info->mru_default;
+
+	if (info->sideband_wake) {
+		mhi_cntrl->wake_get = mhi_pci_wake_get_nop;
+		mhi_cntrl->wake_put = mhi_pci_wake_put_nop;
+		mhi_cntrl->wake_toggle = mhi_pci_wake_toggle_nop;
+	}
+
+	err = mhi_pci_claim(mhi_cntrl, info->bar_num, DMA_BIT_MASK(info->dma_data_width));
+	if (err)
+		return err;
+
+	err = mhi_pci_get_irqs(mhi_cntrl, mhi_cntrl_config);
+	if (err)
+		return err;
+
+	pci_set_drvdata(pdev, mhi_pdev);
+
+	/* Have stored pci confspace at hand for restore in sudden PCI error.
+	 * cache the state locally and discard the PCI core one.
+	 */
+	pci_save_state(pdev);
+	mhi_pdev->pci_state = pci_store_saved_state(pdev);
+	pci_load_saved_state(pdev, NULL);
+
+	pci_enable_pcie_error_reporting(pdev);
+
+	err = mhi_register_controller(mhi_cntrl, mhi_cntrl_config);
+	if (err)
+		goto err_disable_reporting;
+
+	/* MHI bus does not power up the controller by default */
+	err = mhi_prepare_for_power_up(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to prepare MHI controller\n");
+		goto err_unregister;
+	}
+
+	err = mhi_sync_power_up(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to power up MHI controller\n");
+		goto err_unprepare;
+	}
+
+	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
+
+	/* start health check */
+	mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
+
+	/* Only allow runtime-suspend if PME capable (for wakeup) */
+	if (pci_pme_capable(pdev, PCI_D3hot)) {
+		pm_runtime_set_autosuspend_delay(&pdev->dev, 2000);
+		pm_runtime_use_autosuspend(&pdev->dev);
+		pm_runtime_mark_last_busy(&pdev->dev);
+		pm_runtime_put_noidle(&pdev->dev);
+	}
+
+	return 0;
+
+err_unprepare:
+	mhi_unprepare_after_power_down(mhi_cntrl);
+err_unregister:
+	mhi_unregister_controller(mhi_cntrl);
+err_disable_reporting:
+	pci_disable_pcie_error_reporting(pdev);
+
+	return err;
+}
+
+static void mhi_pci_remove(struct pci_dev *pdev)
+{
+	struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	del_timer_sync(&mhi_pdev->health_check_timer);
+	cancel_work_sync(&mhi_pdev->recovery_work);
+
+	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
+		mhi_power_down(mhi_cntrl, true);
+		mhi_unprepare_after_power_down(mhi_cntrl);
+	}
+
+	/* balancing probe put_noidle */
+	if (pci_pme_capable(pdev, PCI_D3hot))
+		pm_runtime_get_noresume(&pdev->dev);
+
+	mhi_unregister_controller(mhi_cntrl);
+	pci_disable_pcie_error_reporting(pdev);
+}
+
+static void mhi_pci_shutdown(struct pci_dev *pdev)
+{
+	mhi_pci_remove(pdev);
+	pci_set_power_state(pdev, PCI_D3hot);
+}
+
+static void mhi_pci_reset_prepare(struct pci_dev *pdev)
+{
+	struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	dev_info(&pdev->dev, "reset\n");
+
+	del_timer(&mhi_pdev->health_check_timer);
+
+	/* Clean up MHI state */
+	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
+		mhi_power_down(mhi_cntrl, false);
+		mhi_unprepare_after_power_down(mhi_cntrl);
+	}
+
+	/* cause internal device reset */
+	mhi_soc_reset(mhi_cntrl);
+
+	/* Be sure device reset has been executed */
+	msleep(MHI_POST_RESET_DELAY_MS);
+}
+
+static void mhi_pci_reset_done(struct pci_dev *pdev)
+{
+	struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+	int err;
+
+	/* Restore initial known working PCI state */
+	pci_load_saved_state(pdev, mhi_pdev->pci_state);
+	pci_restore_state(pdev);
+
+	/* Is device status available ? */
+	if (!mhi_pci_is_alive(mhi_cntrl)) {
+		dev_err(&pdev->dev, "reset failed\n");
+		return;
+	}
+
+	err = mhi_prepare_for_power_up(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to prepare MHI controller\n");
+		return;
+	}
+
+	err = mhi_sync_power_up(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to power up MHI controller\n");
+		mhi_unprepare_after_power_down(mhi_cntrl);
+		return;
+	}
+
+	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
+	mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
+}
+
+static pci_ers_result_t mhi_pci_error_detected(struct pci_dev *pdev,
+					       pci_channel_state_t state)
+{
+	struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	dev_err(&pdev->dev, "PCI error detected, state = %u\n", state);
+
+	if (state == pci_channel_io_perm_failure)
+		return PCI_ERS_RESULT_DISCONNECT;
+
+	/* Clean up MHI state */
+	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
+		mhi_power_down(mhi_cntrl, false);
+		mhi_unprepare_after_power_down(mhi_cntrl);
+	} else {
+		/* Nothing to do */
+		return PCI_ERS_RESULT_RECOVERED;
+	}
+
+	pci_disable_device(pdev);
+
+	return PCI_ERS_RESULT_NEED_RESET;
+}
+
+static pci_ers_result_t mhi_pci_slot_reset(struct pci_dev *pdev)
+{
+	if (pci_enable_device(pdev)) {
+		dev_err(&pdev->dev, "Cannot re-enable PCI device after reset.\n");
+		return PCI_ERS_RESULT_DISCONNECT;
+	}
+
+	return PCI_ERS_RESULT_RECOVERED;
+}
+
+static void mhi_pci_io_resume(struct pci_dev *pdev)
+{
+	struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev);
+
+	dev_err(&pdev->dev, "PCI slot reset done\n");
+
+	queue_work(system_long_wq, &mhi_pdev->recovery_work);
+}
+
+static const struct pci_error_handlers mhi_pci_err_handler = {
+	.error_detected = mhi_pci_error_detected,
+	.slot_reset = mhi_pci_slot_reset,
+	.resume = mhi_pci_io_resume,
+	.reset_prepare = mhi_pci_reset_prepare,
+	.reset_done = mhi_pci_reset_done,
+};
+
+static int  __maybe_unused mhi_pci_runtime_suspend(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+	int err;
+
+	if (test_and_set_bit(MHI_PCI_DEV_SUSPENDED, &mhi_pdev->status))
+		return 0;
+
+	del_timer(&mhi_pdev->health_check_timer);
+	cancel_work_sync(&mhi_pdev->recovery_work);
+
+	if (!test_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status) ||
+			mhi_cntrl->ee != MHI_EE_AMSS)
+		goto pci_suspend; /* Nothing to do at MHI level */
+
+	/* Transition to M3 state */
+	err = mhi_pm_suspend(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to suspend device: %d\n", err);
+		clear_bit(MHI_PCI_DEV_SUSPENDED, &mhi_pdev->status);
+		return -EBUSY;
+	}
+
+pci_suspend:
+	pci_disable_device(pdev);
+	pci_wake_from_d3(pdev, true);
+
+	return 0;
+}
+
+static int __maybe_unused mhi_pci_runtime_resume(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+	int err;
+
+	if (!test_and_clear_bit(MHI_PCI_DEV_SUSPENDED, &mhi_pdev->status))
+		return 0;
+
+	err = pci_enable_device(pdev);
+	if (err)
+		goto err_recovery;
+
+	pci_set_master(pdev);
+	pci_wake_from_d3(pdev, false);
+
+	if (!test_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status) ||
+			mhi_cntrl->ee != MHI_EE_AMSS)
+		return 0; /* Nothing to do at MHI level */
+
+	/* Exit M3, transition to M0 state */
+	err = mhi_pm_resume(mhi_cntrl);
+	if (err) {
+		dev_err(&pdev->dev, "failed to resume device: %d\n", err);
+		goto err_recovery;
+	}
+
+	/* Resume health check */
+	mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
+
+	/* It can be a remote wakeup (no mhi runtime_get), update access time */
+	pm_runtime_mark_last_busy(dev);
+
+	return 0;
+
+err_recovery:
+	/* Do not fail to not mess up our PCI device state, the device likely
+	 * lost power (d3cold) and we simply need to reset it from the recovery
+	 * procedure, trigger the recovery asynchronously to prevent system
+	 * suspend exit delaying.
+	 */
+	queue_work(system_long_wq, &mhi_pdev->recovery_work);
+	pm_runtime_mark_last_busy(dev);
+
+	return 0;
+}
+
+static int  __maybe_unused mhi_pci_suspend(struct device *dev)
+{
+	pm_runtime_disable(dev);
+	return mhi_pci_runtime_suspend(dev);
+}
+
+static int __maybe_unused mhi_pci_resume(struct device *dev)
+{
+	int ret;
+
+	/* Depending the platform, device may have lost power (d3cold), we need
+	 * to resume it now to check its state and recover when necessary.
+	 */
+	ret = mhi_pci_runtime_resume(dev);
+	pm_runtime_enable(dev);
+
+	return ret;
+}
+
+static int __maybe_unused mhi_pci_freeze(struct device *dev)
+{
+	struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev);
+	struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl;
+
+	/* We want to stop all operations, hibernation does not guarantee that
+	 * device will be in the same state as before freezing, especially if
+	 * the intermediate restore kernel reinitializes MHI device with new
+	 * context.
+	 */
+	flush_work(&mhi_pdev->recovery_work);
+	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
+		mhi_power_down(mhi_cntrl, true);
+		mhi_unprepare_after_power_down(mhi_cntrl);
+	}
+
+	return 0;
+}
+
+static int __maybe_unused mhi_pci_restore(struct device *dev)
+{
+	struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev);
+
+	/* Reinitialize the device */
+	queue_work(system_long_wq, &mhi_pdev->recovery_work);
+
+	return 0;
+}
+
+static const struct dev_pm_ops mhi_pci_pm_ops = {
+	SET_RUNTIME_PM_OPS(mhi_pci_runtime_suspend, mhi_pci_runtime_resume, NULL)
+#ifdef CONFIG_PM_SLEEP
+	.suspend = mhi_pci_suspend,
+	.resume = mhi_pci_resume,
+	.freeze = mhi_pci_freeze,
+	.thaw = mhi_pci_restore,
+	.poweroff = mhi_pci_freeze,
+	.restore = mhi_pci_restore,
+#endif
+};
+
+static struct pci_driver mhi_pci_driver = {
+	.name		= "mhi-pci-generic",
+	.id_table	= mhi_pci_id_table,
+	.probe		= mhi_pci_probe,
+	.remove		= mhi_pci_remove,
+	.shutdown	= mhi_pci_shutdown,
+	.err_handler	= &mhi_pci_err_handler,
+	.driver.pm	= &mhi_pci_pm_ops
+};
+module_pci_driver(mhi_pci_driver);
+
+MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
+MODULE_DESCRIPTION("Modem Host Interface (MHI) PCI controller driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/bus/mhi/host/pm.c b/drivers/bus/mhi/host/pm.c
new file mode 100644
index 000000000..8a4362d75
--- /dev/null
+++ b/drivers/bus/mhi/host/pm.c
@@ -0,0 +1,1283 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include "internal.h"
+
+/*
+ * Not all MHI state transitions are synchronous. Transitions like Linkdown,
+ * SYS_ERR, and shutdown can happen anytime asynchronously. This function will
+ * transition to a new state only if we're allowed to.
+ *
+ * Priority increases as we go down. For instance, from any state in L0, the
+ * transition can be made to states in L1, L2 and L3. A notable exception to
+ * this rule is state DISABLE.  From DISABLE state we can only transition to
+ * POR state. Also, while in L2 state, user cannot jump back to previous
+ * L1 or L0 states.
+ *
+ * Valid transitions:
+ * L0: DISABLE <--> POR
+ *     POR <--> POR
+ *     POR -> M0 -> M2 --> M0
+ *     POR -> FW_DL_ERR
+ *     FW_DL_ERR <--> FW_DL_ERR
+ *     M0 <--> M0
+ *     M0 -> FW_DL_ERR
+ *     M0 -> M3_ENTER -> M3 -> M3_EXIT --> M0
+ * L1: SYS_ERR_DETECT -> SYS_ERR_PROCESS --> POR
+ * L2: SHUTDOWN_PROCESS -> LD_ERR_FATAL_DETECT
+ *     SHUTDOWN_PROCESS -> DISABLE
+ * L3: LD_ERR_FATAL_DETECT <--> LD_ERR_FATAL_DETECT
+ *     LD_ERR_FATAL_DETECT -> DISABLE
+ */
+static const struct mhi_pm_transitions dev_state_transitions[] = {
+	/* L0 States */
+	{
+		MHI_PM_DISABLE,
+		MHI_PM_POR
+	},
+	{
+		MHI_PM_POR,
+		MHI_PM_POR | MHI_PM_DISABLE | MHI_PM_M0 |
+		MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_FW_DL_ERR
+	},
+	{
+		MHI_PM_M0,
+		MHI_PM_M0 | MHI_PM_M2 | MHI_PM_M3_ENTER |
+		MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_FW_DL_ERR
+	},
+	{
+		MHI_PM_M2,
+		MHI_PM_M0 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	{
+		MHI_PM_M3_ENTER,
+		MHI_PM_M3 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	{
+		MHI_PM_M3,
+		MHI_PM_M3_EXIT | MHI_PM_SYS_ERR_DETECT |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	{
+		MHI_PM_M3_EXIT,
+		MHI_PM_M0 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	{
+		MHI_PM_FW_DL_ERR,
+		MHI_PM_FW_DL_ERR | MHI_PM_SYS_ERR_DETECT |
+		MHI_PM_SHUTDOWN_PROCESS | MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	/* L1 States */
+	{
+		MHI_PM_SYS_ERR_DETECT,
+		MHI_PM_SYS_ERR_PROCESS | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	{
+		MHI_PM_SYS_ERR_PROCESS,
+		MHI_PM_POR | MHI_PM_SHUTDOWN_PROCESS |
+		MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	/* L2 States */
+	{
+		MHI_PM_SHUTDOWN_PROCESS,
+		MHI_PM_DISABLE | MHI_PM_LD_ERR_FATAL_DETECT
+	},
+	/* L3 States */
+	{
+		MHI_PM_LD_ERR_FATAL_DETECT,
+		MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_DISABLE
+	},
+};
+
+enum mhi_pm_state __must_check mhi_tryset_pm_state(struct mhi_controller *mhi_cntrl,
+						   enum mhi_pm_state state)
+{
+	unsigned long cur_state = mhi_cntrl->pm_state;
+	int index = find_last_bit(&cur_state, 32);
+
+	if (unlikely(index >= ARRAY_SIZE(dev_state_transitions)))
+		return cur_state;
+
+	if (unlikely(dev_state_transitions[index].from_state != cur_state))
+		return cur_state;
+
+	if (unlikely(!(dev_state_transitions[index].to_states & state)))
+		return cur_state;
+
+	mhi_cntrl->pm_state = state;
+	return mhi_cntrl->pm_state;
+}
+
+void mhi_set_mhi_state(struct mhi_controller *mhi_cntrl, enum mhi_state state)
+{
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int ret;
+
+	if (state == MHI_STATE_RESET) {
+		ret = mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+					  MHICTRL_RESET_MASK, 1);
+	} else {
+		ret = mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+					  MHICTRL_MHISTATE_MASK, state);
+	}
+
+	if (ret)
+		dev_err(dev, "Failed to set MHI state to: %s\n",
+			mhi_state_str(state));
+}
+
+/* NOP for backward compatibility, host allowed to ring DB in M2 state */
+static void mhi_toggle_dev_wake_nop(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static void mhi_toggle_dev_wake(struct mhi_controller *mhi_cntrl)
+{
+	mhi_cntrl->wake_get(mhi_cntrl, false);
+	mhi_cntrl->wake_put(mhi_cntrl, true);
+}
+
+/* Handle device ready state transition */
+int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_event *mhi_event;
+	enum mhi_pm_state cur_state;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 interval_us = 25000; /* poll register field every 25 milliseconds */
+	int ret, i;
+
+	/* Check if device entered error state */
+	if (MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) {
+		dev_err(dev, "Device link is not accessible\n");
+		return -EIO;
+	}
+
+	/* Wait for RESET to be cleared and READY bit to be set by the device */
+	ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+				 MHICTRL_RESET_MASK, 0, interval_us);
+	if (ret) {
+		dev_err(dev, "Device failed to clear MHI Reset\n");
+		return ret;
+	}
+
+	ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHISTATUS,
+				 MHISTATUS_READY_MASK, 1, interval_us);
+	if (ret) {
+		dev_err(dev, "Device failed to enter MHI Ready\n");
+		return ret;
+	}
+
+	dev_dbg(dev, "Device in READY State\n");
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_POR);
+	mhi_cntrl->dev_state = MHI_STATE_READY;
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	if (cur_state != MHI_PM_POR) {
+		dev_err(dev, "Error moving to state %s from %s\n",
+			to_mhi_pm_state_str(MHI_PM_POR),
+			to_mhi_pm_state_str(cur_state));
+		return -EIO;
+	}
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+		dev_err(dev, "Device registers not accessible\n");
+		goto error_mmio;
+	}
+
+	/* Configure MMIO registers */
+	ret = mhi_init_mmio(mhi_cntrl);
+	if (ret) {
+		dev_err(dev, "Error configuring MMIO registers\n");
+		goto error_mmio;
+	}
+
+	/* Add elements to all SW event rings */
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		/* Skip if this is an offload or HW event */
+		if (mhi_event->offload_ev || mhi_event->hw_ring)
+			continue;
+
+		ring->wp = ring->base + ring->len - ring->el_size;
+		*ring->ctxt_wp = cpu_to_le64(ring->iommu_base + ring->len - ring->el_size);
+		/* Update all cores */
+		smp_wmb();
+
+		/* Ring the event ring db */
+		spin_lock_irq(&mhi_event->lock);
+		mhi_ring_er_db(mhi_event);
+		spin_unlock_irq(&mhi_event->lock);
+	}
+
+	/* Set MHI to M0 state */
+	mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M0);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	return 0;
+
+error_mmio:
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	return -EIO;
+}
+
+int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl)
+{
+	enum mhi_pm_state cur_state;
+	struct mhi_chan *mhi_chan;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int i;
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	mhi_cntrl->dev_state = MHI_STATE_M0;
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M0);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	if (unlikely(cur_state != MHI_PM_M0)) {
+		dev_err(dev, "Unable to transition to M0 state\n");
+		return -EIO;
+	}
+	mhi_cntrl->M0++;
+
+	/* Wake up the device */
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	mhi_cntrl->wake_get(mhi_cntrl, true);
+
+	/* Ring all event rings and CMD ring only if we're in mission mode */
+	if (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) {
+		struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+		struct mhi_cmd *mhi_cmd =
+			&mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING];
+
+		for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+			if (mhi_event->offload_ev)
+				continue;
+
+			spin_lock_irq(&mhi_event->lock);
+			mhi_ring_er_db(mhi_event);
+			spin_unlock_irq(&mhi_event->lock);
+		}
+
+		/* Only ring primary cmd ring if ring is not empty */
+		spin_lock_irq(&mhi_cmd->lock);
+		if (mhi_cmd->ring.rp != mhi_cmd->ring.wp)
+			mhi_ring_cmd_db(mhi_cntrl, mhi_cmd);
+		spin_unlock_irq(&mhi_cmd->lock);
+	}
+
+	/* Ring channel DB registers */
+	mhi_chan = mhi_cntrl->mhi_chan;
+	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
+		struct mhi_ring *tre_ring = &mhi_chan->tre_ring;
+
+		if (mhi_chan->db_cfg.reset_req) {
+			write_lock_irq(&mhi_chan->lock);
+			mhi_chan->db_cfg.db_mode = true;
+			write_unlock_irq(&mhi_chan->lock);
+		}
+
+		read_lock_irq(&mhi_chan->lock);
+
+		/* Only ring DB if ring is not empty */
+		if (tre_ring->base && tre_ring->wp  != tre_ring->rp &&
+		    mhi_chan->ch_state == MHI_CH_STATE_ENABLED)
+			mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+		read_unlock_irq(&mhi_chan->lock);
+	}
+
+	mhi_cntrl->wake_put(mhi_cntrl, false);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+	wake_up_all(&mhi_cntrl->state_event);
+
+	return 0;
+}
+
+/*
+ * After receiving the MHI state change event from the device indicating the
+ * transition to M1 state, the host can transition the device to M2 state
+ * for keeping it in low power state.
+ */
+void mhi_pm_m1_transition(struct mhi_controller *mhi_cntrl)
+{
+	enum mhi_pm_state state;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M2);
+	if (state == MHI_PM_M2) {
+		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M2);
+		mhi_cntrl->dev_state = MHI_STATE_M2;
+
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+
+		mhi_cntrl->M2++;
+		wake_up_all(&mhi_cntrl->state_event);
+
+		/* If there are any pending resources, exit M2 immediately */
+		if (unlikely(atomic_read(&mhi_cntrl->pending_pkts) ||
+			     atomic_read(&mhi_cntrl->dev_wake))) {
+			dev_dbg(dev,
+				"Exiting M2, pending_pkts: %d dev_wake: %d\n",
+				atomic_read(&mhi_cntrl->pending_pkts),
+				atomic_read(&mhi_cntrl->dev_wake));
+			read_lock_bh(&mhi_cntrl->pm_lock);
+			mhi_cntrl->wake_get(mhi_cntrl, true);
+			mhi_cntrl->wake_put(mhi_cntrl, true);
+			read_unlock_bh(&mhi_cntrl->pm_lock);
+		} else {
+			mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_IDLE);
+		}
+	} else {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+	}
+}
+
+/* MHI M3 completion handler */
+int mhi_pm_m3_transition(struct mhi_controller *mhi_cntrl)
+{
+	enum mhi_pm_state state;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	mhi_cntrl->dev_state = MHI_STATE_M3;
+	state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	if (state != MHI_PM_M3) {
+		dev_err(dev, "Unable to transition to M3 state\n");
+		return -EIO;
+	}
+
+	mhi_cntrl->M3++;
+	wake_up_all(&mhi_cntrl->state_event);
+
+	return 0;
+}
+
+/* Handle device Mission Mode transition */
+static int mhi_pm_mission_mode_transition(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_event *mhi_event;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_ee_type ee = MHI_EE_MAX, current_ee = mhi_cntrl->ee;
+	int i, ret;
+
+	dev_dbg(dev, "Processing Mission Mode transition\n");
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+		ee = mhi_get_exec_env(mhi_cntrl);
+
+	if (!MHI_IN_MISSION_MODE(ee)) {
+		mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		wake_up_all(&mhi_cntrl->state_event);
+		return -EIO;
+	}
+	mhi_cntrl->ee = ee;
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	wake_up_all(&mhi_cntrl->state_event);
+
+	device_for_each_child(&mhi_cntrl->mhi_dev->dev, &current_ee,
+			      mhi_destroy_device);
+	mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_EE_MISSION_MODE);
+
+	/* Force MHI to be in M0 state before continuing */
+	ret = __mhi_device_get_sync(mhi_cntrl);
+	if (ret)
+		return ret;
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		ret = -EIO;
+		goto error_mission_mode;
+	}
+
+	/* Add elements to all HW event rings */
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		if (mhi_event->offload_ev || !mhi_event->hw_ring)
+			continue;
+
+		ring->wp = ring->base + ring->len - ring->el_size;
+		*ring->ctxt_wp = cpu_to_le64(ring->iommu_base + ring->len - ring->el_size);
+		/* Update to all cores */
+		smp_wmb();
+
+		spin_lock_irq(&mhi_event->lock);
+		if (MHI_DB_ACCESS_VALID(mhi_cntrl))
+			mhi_ring_er_db(mhi_event);
+		spin_unlock_irq(&mhi_event->lock);
+	}
+
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	/*
+	 * The MHI devices are only created when the client device switches its
+	 * Execution Environment (EE) to either SBL or AMSS states
+	 */
+	mhi_create_devices(mhi_cntrl);
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+
+error_mission_mode:
+	mhi_cntrl->wake_put(mhi_cntrl, false);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	return ret;
+}
+
+/* Handle shutdown transitions */
+static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl)
+{
+	enum mhi_pm_state cur_state;
+	struct mhi_event *mhi_event;
+	struct mhi_cmd_ctxt *cmd_ctxt;
+	struct mhi_cmd *mhi_cmd;
+	struct mhi_event_ctxt *er_ctxt;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int ret, i;
+
+	dev_dbg(dev, "Processing disable transition with PM state: %s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state));
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+
+	/* Trigger MHI RESET so that the device will not access host memory */
+	if (!MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) {
+		/* Skip MHI RESET if in RDDM state */
+		if (mhi_cntrl->rddm_image && mhi_get_exec_env(mhi_cntrl) == MHI_EE_RDDM)
+			goto skip_mhi_reset;
+
+		dev_dbg(dev, "Triggering MHI Reset in device\n");
+		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+
+		/* Wait for the reset bit to be cleared by the device */
+		ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+				 MHICTRL_RESET_MASK, 0, 25000);
+		if (ret)
+			dev_err(dev, "Device failed to clear MHI Reset\n");
+
+		/*
+		 * Device will clear BHI_INTVEC as a part of RESET processing,
+		 * hence re-program it
+		 */
+		mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+
+		if (!MHI_IN_PBL(mhi_get_exec_env(mhi_cntrl))) {
+			/* wait for ready to be set */
+			ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs,
+						 MHISTATUS,
+						 MHISTATUS_READY_MASK, 1, 25000);
+			if (ret)
+				dev_err(dev, "Device failed to enter READY state\n");
+		}
+	}
+
+skip_mhi_reset:
+	dev_dbg(dev,
+		 "Waiting for all pending event ring processing to complete\n");
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+		disable_irq(mhi_cntrl->irq[mhi_event->irq]);
+		tasklet_kill(&mhi_event->task);
+	}
+
+	/* Release lock and wait for all pending threads to complete */
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+	dev_dbg(dev, "Waiting for all pending threads to complete\n");
+	wake_up_all(&mhi_cntrl->state_event);
+
+	dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
+	device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+
+	WARN_ON(atomic_read(&mhi_cntrl->dev_wake));
+	WARN_ON(atomic_read(&mhi_cntrl->pending_pkts));
+
+	/* Reset the ev rings and cmd rings */
+	dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n");
+	mhi_cmd = mhi_cntrl->mhi_cmd;
+	cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt;
+	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
+		struct mhi_ring *ring = &mhi_cmd->ring;
+
+		ring->rp = ring->base;
+		ring->wp = ring->base;
+		cmd_ctxt->rp = cmd_ctxt->rbase;
+		cmd_ctxt->wp = cmd_ctxt->rbase;
+	}
+
+	mhi_event = mhi_cntrl->mhi_event;
+	er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
+		     mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		/* Skip offload events */
+		if (mhi_event->offload_ev)
+			continue;
+
+		ring->rp = ring->base;
+		ring->wp = ring->base;
+		er_ctxt->rp = er_ctxt->rbase;
+		er_ctxt->wp = er_ctxt->rbase;
+	}
+
+	/* Move to disable state */
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_DISABLE);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	if (unlikely(cur_state != MHI_PM_DISABLE))
+		dev_err(dev, "Error moving from PM state: %s to: %s\n",
+			to_mhi_pm_state_str(cur_state),
+			to_mhi_pm_state_str(MHI_PM_DISABLE));
+
+	dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		mhi_state_str(mhi_cntrl->dev_state));
+
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+}
+
+/* Handle system error transitions */
+static void mhi_pm_sys_error_transition(struct mhi_controller *mhi_cntrl)
+{
+	enum mhi_pm_state cur_state, prev_state;
+	enum dev_st_transition next_state;
+	struct mhi_event *mhi_event;
+	struct mhi_cmd_ctxt *cmd_ctxt;
+	struct mhi_cmd *mhi_cmd;
+	struct mhi_event_ctxt *er_ctxt;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int ret, i;
+
+	dev_dbg(dev, "Transitioning from PM state: %s to: %s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS));
+
+	/* We must notify MHI control driver so it can clean up first */
+	mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_SYS_ERROR);
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	prev_state = mhi_cntrl->pm_state;
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	if (cur_state != MHI_PM_SYS_ERR_PROCESS) {
+		dev_err(dev, "Failed to transition from PM state: %s to: %s\n",
+			to_mhi_pm_state_str(cur_state),
+			to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS));
+		goto exit_sys_error_transition;
+	}
+
+	mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION;
+	mhi_cntrl->dev_state = MHI_STATE_RESET;
+
+	/* Wake up threads waiting for state transition */
+	wake_up_all(&mhi_cntrl->state_event);
+
+	/* Trigger MHI RESET so that the device will not access host memory */
+	if (MHI_REG_ACCESS_VALID(prev_state)) {
+		u32 in_reset = -1;
+		unsigned long timeout = msecs_to_jiffies(mhi_cntrl->timeout_ms);
+
+		dev_dbg(dev, "Triggering MHI Reset in device\n");
+		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+
+		/* Wait for the reset bit to be cleared by the device */
+		ret = wait_event_timeout(mhi_cntrl->state_event,
+					 mhi_read_reg_field(mhi_cntrl,
+							    mhi_cntrl->regs,
+							    MHICTRL,
+							    MHICTRL_RESET_MASK,
+							    &in_reset) ||
+					!in_reset, timeout);
+		if (!ret || in_reset) {
+			dev_err(dev, "Device failed to exit MHI Reset state\n");
+			goto exit_sys_error_transition;
+		}
+
+		/*
+		 * Device will clear BHI_INTVEC as a part of RESET processing,
+		 * hence re-program it
+		 */
+		mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+	}
+
+	dev_dbg(dev,
+		"Waiting for all pending event ring processing to complete\n");
+	mhi_event = mhi_cntrl->mhi_event;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+		tasklet_kill(&mhi_event->task);
+	}
+
+	/* Release lock and wait for all pending threads to complete */
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+	dev_dbg(dev, "Waiting for all pending threads to complete\n");
+	wake_up_all(&mhi_cntrl->state_event);
+
+	dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
+	device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+
+	WARN_ON(atomic_read(&mhi_cntrl->dev_wake));
+	WARN_ON(atomic_read(&mhi_cntrl->pending_pkts));
+
+	/* Reset the ev rings and cmd rings */
+	dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n");
+	mhi_cmd = mhi_cntrl->mhi_cmd;
+	cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt;
+	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
+		struct mhi_ring *ring = &mhi_cmd->ring;
+
+		ring->rp = ring->base;
+		ring->wp = ring->base;
+		cmd_ctxt->rp = cmd_ctxt->rbase;
+		cmd_ctxt->wp = cmd_ctxt->rbase;
+	}
+
+	mhi_event = mhi_cntrl->mhi_event;
+	er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
+	     mhi_event++) {
+		struct mhi_ring *ring = &mhi_event->ring;
+
+		/* Skip offload events */
+		if (mhi_event->offload_ev)
+			continue;
+
+		ring->rp = ring->base;
+		ring->wp = ring->base;
+		er_ctxt->rp = er_ctxt->rbase;
+		er_ctxt->wp = er_ctxt->rbase;
+	}
+
+	/* Transition to next state */
+	if (MHI_IN_PBL(mhi_get_exec_env(mhi_cntrl))) {
+		write_lock_irq(&mhi_cntrl->pm_lock);
+		cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_POR);
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		if (cur_state != MHI_PM_POR) {
+			dev_err(dev, "Error moving to state %s from %s\n",
+				to_mhi_pm_state_str(MHI_PM_POR),
+				to_mhi_pm_state_str(cur_state));
+			goto exit_sys_error_transition;
+		}
+		next_state = DEV_ST_TRANSITION_PBL;
+	} else {
+		next_state = DEV_ST_TRANSITION_READY;
+	}
+
+	mhi_queue_state_transition(mhi_cntrl, next_state);
+
+exit_sys_error_transition:
+	dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		mhi_state_str(mhi_cntrl->dev_state));
+
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+}
+
+/* Queue a new work item and schedule work */
+int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
+			       enum dev_st_transition state)
+{
+	struct state_transition *item = kmalloc(sizeof(*item), GFP_ATOMIC);
+	unsigned long flags;
+
+	if (!item)
+		return -ENOMEM;
+
+	item->state = state;
+	spin_lock_irqsave(&mhi_cntrl->transition_lock, flags);
+	list_add_tail(&item->node, &mhi_cntrl->transition_list);
+	spin_unlock_irqrestore(&mhi_cntrl->transition_lock, flags);
+
+	queue_work(mhi_cntrl->hiprio_wq, &mhi_cntrl->st_worker);
+
+	return 0;
+}
+
+/* SYS_ERR worker */
+void mhi_pm_sys_err_handler(struct mhi_controller *mhi_cntrl)
+{
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	/* skip if controller supports RDDM */
+	if (mhi_cntrl->rddm_image) {
+		dev_dbg(dev, "Controller supports RDDM, skip SYS_ERROR\n");
+		return;
+	}
+
+	mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_SYS_ERR);
+}
+
+/* Device State Transition worker */
+void mhi_pm_st_worker(struct work_struct *work)
+{
+	struct state_transition *itr, *tmp;
+	LIST_HEAD(head);
+	struct mhi_controller *mhi_cntrl = container_of(work,
+							struct mhi_controller,
+							st_worker);
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	spin_lock_irq(&mhi_cntrl->transition_lock);
+	list_splice_tail_init(&mhi_cntrl->transition_list, &head);
+	spin_unlock_irq(&mhi_cntrl->transition_lock);
+
+	list_for_each_entry_safe(itr, tmp, &head, node) {
+		list_del(&itr->node);
+		dev_dbg(dev, "Handling state transition: %s\n",
+			TO_DEV_STATE_TRANS_STR(itr->state));
+
+		switch (itr->state) {
+		case DEV_ST_TRANSITION_PBL:
+			write_lock_irq(&mhi_cntrl->pm_lock);
+			if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+				mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
+			write_unlock_irq(&mhi_cntrl->pm_lock);
+			mhi_fw_load_handler(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_SBL:
+			write_lock_irq(&mhi_cntrl->pm_lock);
+			mhi_cntrl->ee = MHI_EE_SBL;
+			write_unlock_irq(&mhi_cntrl->pm_lock);
+			/*
+			 * The MHI devices are only created when the client
+			 * device switches its Execution Environment (EE) to
+			 * either SBL or AMSS states
+			 */
+			mhi_create_devices(mhi_cntrl);
+			if (mhi_cntrl->fbc_download)
+				mhi_download_amss_image(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_MISSION_MODE:
+			mhi_pm_mission_mode_transition(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_FP:
+			write_lock_irq(&mhi_cntrl->pm_lock);
+			mhi_cntrl->ee = MHI_EE_FP;
+			write_unlock_irq(&mhi_cntrl->pm_lock);
+			mhi_create_devices(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_READY:
+			mhi_ready_state_transition(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_SYS_ERR:
+			mhi_pm_sys_error_transition(mhi_cntrl);
+			break;
+		case DEV_ST_TRANSITION_DISABLE:
+			mhi_pm_disable_transition(mhi_cntrl);
+			break;
+		default:
+			break;
+		}
+		kfree(itr);
+	}
+}
+
+int mhi_pm_suspend(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_chan *itr, *tmp;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_pm_state new_state;
+	int ret;
+
+	if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
+		return -EINVAL;
+
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+		return -EIO;
+
+	/* Return busy if there are any pending resources */
+	if (atomic_read(&mhi_cntrl->dev_wake) ||
+	    atomic_read(&mhi_cntrl->pending_pkts))
+		return -EBUSY;
+
+	/* Take MHI out of M2 state */
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	mhi_cntrl->wake_get(mhi_cntrl, false);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 mhi_cntrl->dev_state == MHI_STATE_M0 ||
+				 mhi_cntrl->dev_state == MHI_STATE_M1 ||
+				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	mhi_cntrl->wake_put(mhi_cntrl, false);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		dev_err(dev,
+			"Could not enter M0/M1 state");
+		return -EIO;
+	}
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+
+	if (atomic_read(&mhi_cntrl->dev_wake) ||
+	    atomic_read(&mhi_cntrl->pending_pkts)) {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		return -EBUSY;
+	}
+
+	dev_dbg(dev, "Allowing M3 transition\n");
+	new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3_ENTER);
+	if (new_state != MHI_PM_M3_ENTER) {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		dev_err(dev,
+			"Error setting to PM state: %s from: %s\n",
+			to_mhi_pm_state_str(MHI_PM_M3_ENTER),
+			to_mhi_pm_state_str(mhi_cntrl->pm_state));
+		return -EIO;
+	}
+
+	/* Set MHI to M3 and wait for completion */
+	mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M3);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	dev_dbg(dev, "Waiting for M3 completion\n");
+
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 mhi_cntrl->dev_state == MHI_STATE_M3 ||
+				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		dev_err(dev,
+			"Did not enter M3 state, MHI state: %s, PM state: %s\n",
+			mhi_state_str(mhi_cntrl->dev_state),
+			to_mhi_pm_state_str(mhi_cntrl->pm_state));
+		return -EIO;
+	}
+
+	/* Notify clients about entering LPM */
+	list_for_each_entry_safe(itr, tmp, &mhi_cntrl->lpm_chans, node) {
+		mutex_lock(&itr->mutex);
+		if (itr->mhi_dev)
+			mhi_notify(itr->mhi_dev, MHI_CB_LPM_ENTER);
+		mutex_unlock(&itr->mutex);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mhi_pm_suspend);
+
+static int __mhi_pm_resume(struct mhi_controller *mhi_cntrl, bool force)
+{
+	struct mhi_chan *itr, *tmp;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	enum mhi_pm_state cur_state;
+	int ret;
+
+	dev_dbg(dev, "Entered with PM state: %s, MHI state: %s\n",
+		to_mhi_pm_state_str(mhi_cntrl->pm_state),
+		mhi_state_str(mhi_cntrl->dev_state));
+
+	if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
+		return 0;
+
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+		return -EIO;
+
+	if (mhi_get_mhi_state(mhi_cntrl) != MHI_STATE_M3) {
+		dev_warn(dev, "Resuming from non M3 state (%s)\n",
+			 mhi_state_str(mhi_get_mhi_state(mhi_cntrl)));
+		if (!force)
+			return -EINVAL;
+	}
+
+	/* Notify clients about exiting LPM */
+	list_for_each_entry_safe(itr, tmp, &mhi_cntrl->lpm_chans, node) {
+		mutex_lock(&itr->mutex);
+		if (itr->mhi_dev)
+			mhi_notify(itr->mhi_dev, MHI_CB_LPM_EXIT);
+		mutex_unlock(&itr->mutex);
+	}
+
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3_EXIT);
+	if (cur_state != MHI_PM_M3_EXIT) {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		dev_info(dev,
+			 "Error setting to PM state: %s from: %s\n",
+			 to_mhi_pm_state_str(MHI_PM_M3_EXIT),
+			 to_mhi_pm_state_str(mhi_cntrl->pm_state));
+		return -EIO;
+	}
+
+	/* Set MHI to M0 and wait for completion */
+	mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M0);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 mhi_cntrl->dev_state == MHI_STATE_M0 ||
+				 mhi_cntrl->dev_state == MHI_STATE_M2 ||
+				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		dev_err(dev,
+			"Did not enter M0 state, MHI state: %s, PM state: %s\n",
+			mhi_state_str(mhi_cntrl->dev_state),
+			to_mhi_pm_state_str(mhi_cntrl->pm_state));
+		return -EIO;
+	}
+
+	return 0;
+}
+
+int mhi_pm_resume(struct mhi_controller *mhi_cntrl)
+{
+	return __mhi_pm_resume(mhi_cntrl, false);
+}
+EXPORT_SYMBOL_GPL(mhi_pm_resume);
+
+int mhi_pm_resume_force(struct mhi_controller *mhi_cntrl)
+{
+	return __mhi_pm_resume(mhi_cntrl, true);
+}
+EXPORT_SYMBOL_GPL(mhi_pm_resume_force);
+
+int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl)
+{
+	int ret;
+
+	/* Wake up the device */
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		read_unlock_bh(&mhi_cntrl->pm_lock);
+		return -EIO;
+	}
+	mhi_cntrl->wake_get(mhi_cntrl, true);
+	if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+		mhi_trigger_resume(mhi_cntrl);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 mhi_cntrl->pm_state == MHI_PM_M0 ||
+				 MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+		read_lock_bh(&mhi_cntrl->pm_lock);
+		mhi_cntrl->wake_put(mhi_cntrl, false);
+		read_unlock_bh(&mhi_cntrl->pm_lock);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/* Assert device wake db */
+static void mhi_assert_dev_wake(struct mhi_controller *mhi_cntrl, bool force)
+{
+	unsigned long flags;
+
+	/*
+	 * If force flag is set, then increment the wake count value and
+	 * ring wake db
+	 */
+	if (unlikely(force)) {
+		spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+		atomic_inc(&mhi_cntrl->dev_wake);
+		if (MHI_WAKE_DB_FORCE_SET_VALID(mhi_cntrl->pm_state) &&
+		    !mhi_cntrl->wake_set) {
+			mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 1);
+			mhi_cntrl->wake_set = true;
+		}
+		spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+	} else {
+		/*
+		 * If resources are already requested, then just increment
+		 * the wake count value and return
+		 */
+		if (likely(atomic_add_unless(&mhi_cntrl->dev_wake, 1, 0)))
+			return;
+
+		spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+		if ((atomic_inc_return(&mhi_cntrl->dev_wake) == 1) &&
+		    MHI_WAKE_DB_SET_VALID(mhi_cntrl->pm_state) &&
+		    !mhi_cntrl->wake_set) {
+			mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 1);
+			mhi_cntrl->wake_set = true;
+		}
+		spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+	}
+}
+
+/* De-assert device wake db */
+static void mhi_deassert_dev_wake(struct mhi_controller *mhi_cntrl,
+				  bool override)
+{
+	unsigned long flags;
+
+	/*
+	 * Only continue if there is a single resource, else just decrement
+	 * and return
+	 */
+	if (likely(atomic_add_unless(&mhi_cntrl->dev_wake, -1, 1)))
+		return;
+
+	spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+	if ((atomic_dec_return(&mhi_cntrl->dev_wake) == 0) &&
+	    MHI_WAKE_DB_CLEAR_VALID(mhi_cntrl->pm_state) && !override &&
+	    mhi_cntrl->wake_set) {
+		mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 0);
+		mhi_cntrl->wake_set = false;
+	}
+	spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+}
+
+int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
+{
+	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+	enum mhi_state state;
+	enum mhi_ee_type current_ee;
+	enum dev_st_transition next_state;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	u32 interval_us = 25000; /* poll register field every 25 milliseconds */
+	int ret, i;
+
+	dev_info(dev, "Requested to power ON\n");
+
+	/* Supply default wake routines if not provided by controller driver */
+	if (!mhi_cntrl->wake_get || !mhi_cntrl->wake_put ||
+	    !mhi_cntrl->wake_toggle) {
+		mhi_cntrl->wake_get = mhi_assert_dev_wake;
+		mhi_cntrl->wake_put = mhi_deassert_dev_wake;
+		mhi_cntrl->wake_toggle = (mhi_cntrl->db_access & MHI_PM_M2) ?
+			mhi_toggle_dev_wake_nop : mhi_toggle_dev_wake;
+	}
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+	mhi_cntrl->pm_state = MHI_PM_DISABLE;
+
+	/* Setup BHI INTVEC */
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+	mhi_cntrl->pm_state = MHI_PM_POR;
+	mhi_cntrl->ee = MHI_EE_MAX;
+	current_ee = mhi_get_exec_env(mhi_cntrl);
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+
+	/* Confirm that the device is in valid exec env */
+	if (!MHI_POWER_UP_CAPABLE(current_ee)) {
+		dev_err(dev, "%s is not a valid EE for power on\n",
+			TO_MHI_EXEC_STR(current_ee));
+		ret = -EIO;
+		goto error_exit;
+	}
+
+	state = mhi_get_mhi_state(mhi_cntrl);
+	dev_dbg(dev, "Attempting power on with EE: %s, state: %s\n",
+		TO_MHI_EXEC_STR(current_ee), mhi_state_str(state));
+
+	if (state == MHI_STATE_SYS_ERR) {
+		mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+		ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+				 MHICTRL_RESET_MASK, 0, interval_us);
+		if (ret) {
+			dev_info(dev, "Failed to reset MHI due to syserr state\n");
+			goto error_exit;
+		}
+
+		/*
+		 * device cleares INTVEC as part of RESET processing,
+		 * re-program it
+		 */
+		mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+	}
+
+	/* IRQs have been requested during probe, so we just need to enable them. */
+	enable_irq(mhi_cntrl->irq[0]);
+
+	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+		if (mhi_event->offload_ev)
+			continue;
+
+		enable_irq(mhi_cntrl->irq[mhi_event->irq]);
+	}
+
+	/* Transition to next state */
+	next_state = MHI_IN_PBL(current_ee) ?
+		DEV_ST_TRANSITION_PBL : DEV_ST_TRANSITION_READY;
+
+	mhi_queue_state_transition(mhi_cntrl, next_state);
+
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+
+	dev_info(dev, "Power on setup success\n");
+
+	return 0;
+
+error_exit:
+	mhi_cntrl->pm_state = MHI_PM_DISABLE;
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_async_power_up);
+
+void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
+{
+	enum mhi_pm_state cur_state, transition_state;
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+	mutex_lock(&mhi_cntrl->pm_mutex);
+	write_lock_irq(&mhi_cntrl->pm_lock);
+	cur_state = mhi_cntrl->pm_state;
+	if (cur_state == MHI_PM_DISABLE) {
+		write_unlock_irq(&mhi_cntrl->pm_lock);
+		mutex_unlock(&mhi_cntrl->pm_mutex);
+		return; /* Already powered down */
+	}
+
+	/* If it's not a graceful shutdown, force MHI to linkdown state */
+	transition_state = (graceful) ? MHI_PM_SHUTDOWN_PROCESS :
+			   MHI_PM_LD_ERR_FATAL_DETECT;
+
+	cur_state = mhi_tryset_pm_state(mhi_cntrl, transition_state);
+	if (cur_state != transition_state) {
+		dev_err(dev, "Failed to move to state: %s from: %s\n",
+			to_mhi_pm_state_str(transition_state),
+			to_mhi_pm_state_str(mhi_cntrl->pm_state));
+		/* Force link down or error fatal detected state */
+		mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+	}
+
+	/* mark device inactive to avoid any further host processing */
+	mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION;
+	mhi_cntrl->dev_state = MHI_STATE_RESET;
+
+	wake_up_all(&mhi_cntrl->state_event);
+
+	write_unlock_irq(&mhi_cntrl->pm_lock);
+	mutex_unlock(&mhi_cntrl->pm_mutex);
+
+	mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_DISABLE);
+
+	/* Wait for shutdown to complete */
+	flush_work(&mhi_cntrl->st_worker);
+
+	disable_irq(mhi_cntrl->irq[0]);
+}
+EXPORT_SYMBOL_GPL(mhi_power_down);
+
+int mhi_sync_power_up(struct mhi_controller *mhi_cntrl)
+{
+	int ret = mhi_async_power_up(mhi_cntrl);
+
+	if (ret)
+		return ret;
+
+	wait_event_timeout(mhi_cntrl->state_event,
+			   MHI_IN_MISSION_MODE(mhi_cntrl->ee) ||
+			   MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+	ret = (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) ? 0 : -ETIMEDOUT;
+	if (ret)
+		mhi_power_down(mhi_cntrl, false);
+
+	return ret;
+}
+EXPORT_SYMBOL(mhi_sync_power_up);
+
+int mhi_force_rddm_mode(struct mhi_controller *mhi_cntrl)
+{
+	struct device *dev = &mhi_cntrl->mhi_dev->dev;
+	int ret;
+
+	/* Check if device is already in RDDM */
+	if (mhi_cntrl->ee == MHI_EE_RDDM)
+		return 0;
+
+	dev_dbg(dev, "Triggering SYS_ERR to force RDDM state\n");
+	mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
+
+	/* Wait for RDDM event */
+	ret = wait_event_timeout(mhi_cntrl->state_event,
+				 mhi_cntrl->ee == MHI_EE_RDDM,
+				 msecs_to_jiffies(mhi_cntrl->timeout_ms));
+	ret = ret ? 0 : -EIO;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_force_rddm_mode);
+
+void mhi_device_get(struct mhi_device *mhi_dev)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+	mhi_dev->dev_wake++;
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+		mhi_trigger_resume(mhi_cntrl);
+
+	mhi_cntrl->wake_get(mhi_cntrl, true);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+}
+EXPORT_SYMBOL_GPL(mhi_device_get);
+
+int mhi_device_get_sync(struct mhi_device *mhi_dev)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+	int ret;
+
+	ret = __mhi_device_get_sync(mhi_cntrl);
+	if (!ret)
+		mhi_dev->dev_wake++;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_device_get_sync);
+
+void mhi_device_put(struct mhi_device *mhi_dev)
+{
+	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+	mhi_dev->dev_wake--;
+	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+		mhi_trigger_resume(mhi_cntrl);
+
+	mhi_cntrl->wake_put(mhi_cntrl, false);
+	read_unlock_bh(&mhi_cntrl->pm_lock);
+}
+EXPORT_SYMBOL_GPL(mhi_device_put);