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-rw-r--r--drivers/greybus/es2.c1460
1 files changed, 1460 insertions, 0 deletions
diff --git a/drivers/greybus/es2.c b/drivers/greybus/es2.c
new file mode 100644
index 000000000..e89cca015
--- /dev/null
+++ b/drivers/greybus/es2.c
@@ -0,0 +1,1460 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Greybus "AP" USB driver for "ES2" controller chips
+ *
+ * Copyright 2014-2015 Google Inc.
+ * Copyright 2014-2015 Linaro Ltd.
+ */
+#include <linux/kthread.h>
+#include <linux/sizes.h>
+#include <linux/usb.h>
+#include <linux/kfifo.h>
+#include <linux/debugfs.h>
+#include <linux/list.h>
+#include <linux/greybus.h>
+#include <asm/unaligned.h>
+
+#include "arpc.h"
+#include "greybus_trace.h"
+
+
+/* Default timeout for USB vendor requests. */
+#define ES2_USB_CTRL_TIMEOUT 500
+
+/* Default timeout for ARPC CPort requests */
+#define ES2_ARPC_CPORT_TIMEOUT 500
+
+/* Fixed CPort numbers */
+#define ES2_CPORT_CDSI0 16
+#define ES2_CPORT_CDSI1 17
+
+/* Memory sizes for the buffers sent to/from the ES2 controller */
+#define ES2_GBUF_MSG_SIZE_MAX 2048
+
+/* Memory sizes for the ARPC buffers */
+#define ARPC_OUT_SIZE_MAX U16_MAX
+#define ARPC_IN_SIZE_MAX 128
+
+static const struct usb_device_id id_table[] = {
+ { USB_DEVICE(0x18d1, 0x1eaf) },
+ { },
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+#define APB1_LOG_SIZE SZ_16K
+
+/*
+ * Number of CPort IN urbs in flight at any point in time.
+ * Adjust if we are having stalls in the USB buffer due to not enough urbs in
+ * flight.
+ */
+#define NUM_CPORT_IN_URB 4
+
+/* Number of CPort OUT urbs in flight at any point in time.
+ * Adjust if we get messages saying we are out of urbs in the system log.
+ */
+#define NUM_CPORT_OUT_URB 8
+
+/*
+ * Number of ARPC in urbs in flight at any point in time.
+ */
+#define NUM_ARPC_IN_URB 2
+
+/*
+ * @endpoint: bulk in endpoint for CPort data
+ * @urb: array of urbs for the CPort in messages
+ * @buffer: array of buffers for the @cport_in_urb urbs
+ */
+struct es2_cport_in {
+ __u8 endpoint;
+ struct urb *urb[NUM_CPORT_IN_URB];
+ u8 *buffer[NUM_CPORT_IN_URB];
+};
+
+/**
+ * struct es2_ap_dev - ES2 USB Bridge to AP structure
+ * @usb_dev: pointer to the USB device we are.
+ * @usb_intf: pointer to the USB interface we are bound to.
+ * @hd: pointer to our gb_host_device structure
+ *
+ * @cport_in: endpoint, urbs and buffer for cport in messages
+ * @cport_out_endpoint: endpoint for cport out messages
+ * @cport_out_urb: array of urbs for the CPort out messages
+ * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
+ * not.
+ * @cport_out_urb_cancelled: array of flags indicating whether the
+ * corresponding @cport_out_urb is being cancelled
+ * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
+ * @cdsi1_in_use: true if cport CDSI1 is in use
+ * @apb_log_task: task pointer for logging thread
+ * @apb_log_dentry: file system entry for the log file interface
+ * @apb_log_enable_dentry: file system entry for enabling logging
+ * @apb_log_fifo: kernel FIFO to carry logged data
+ * @arpc_urb: array of urbs for the ARPC in messages
+ * @arpc_buffer: array of buffers for the @arpc_urb urbs
+ * @arpc_endpoint_in: bulk in endpoint for APBridgeA RPC
+ * @arpc_id_cycle: gives an unique id to ARPC
+ * @arpc_lock: locks ARPC list
+ * @arpcs: list of in progress ARPCs
+ */
+struct es2_ap_dev {
+ struct usb_device *usb_dev;
+ struct usb_interface *usb_intf;
+ struct gb_host_device *hd;
+
+ struct es2_cport_in cport_in;
+ __u8 cport_out_endpoint;
+ struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
+ bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
+ bool cport_out_urb_cancelled[NUM_CPORT_OUT_URB];
+ spinlock_t cport_out_urb_lock;
+
+ bool cdsi1_in_use;
+
+ struct task_struct *apb_log_task;
+ struct dentry *apb_log_dentry;
+ struct dentry *apb_log_enable_dentry;
+ DECLARE_KFIFO(apb_log_fifo, char, APB1_LOG_SIZE);
+
+ __u8 arpc_endpoint_in;
+ struct urb *arpc_urb[NUM_ARPC_IN_URB];
+ u8 *arpc_buffer[NUM_ARPC_IN_URB];
+
+ int arpc_id_cycle;
+ spinlock_t arpc_lock;
+ struct list_head arpcs;
+};
+
+struct arpc {
+ struct list_head list;
+ struct arpc_request_message *req;
+ struct arpc_response_message *resp;
+ struct completion response_received;
+ bool active;
+};
+
+static inline struct es2_ap_dev *hd_to_es2(struct gb_host_device *hd)
+{
+ return (struct es2_ap_dev *)&hd->hd_priv;
+}
+
+static void cport_out_callback(struct urb *urb);
+static void usb_log_enable(struct es2_ap_dev *es2);
+static void usb_log_disable(struct es2_ap_dev *es2);
+static int arpc_sync(struct es2_ap_dev *es2, u8 type, void *payload,
+ size_t size, int *result, unsigned int timeout);
+
+static int output_sync(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
+{
+ struct usb_device *udev = es2->usb_dev;
+ u8 *data;
+ int retval;
+
+ data = kmemdup(req, size, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ cmd,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE,
+ 0, 0, data, size, ES2_USB_CTRL_TIMEOUT);
+ if (retval < 0)
+ dev_err(&udev->dev, "%s: return error %d\n", __func__, retval);
+ else
+ retval = 0;
+
+ kfree(data);
+ return retval;
+}
+
+static void ap_urb_complete(struct urb *urb)
+{
+ struct usb_ctrlrequest *dr = urb->context;
+
+ kfree(dr);
+ usb_free_urb(urb);
+}
+
+static int output_async(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
+{
+ struct usb_device *udev = es2->usb_dev;
+ struct urb *urb;
+ struct usb_ctrlrequest *dr;
+ u8 *buf;
+ int retval;
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb)
+ return -ENOMEM;
+
+ dr = kmalloc(sizeof(*dr) + size, GFP_ATOMIC);
+ if (!dr) {
+ usb_free_urb(urb);
+ return -ENOMEM;
+ }
+
+ buf = (u8 *)dr + sizeof(*dr);
+ memcpy(buf, req, size);
+
+ dr->bRequest = cmd;
+ dr->bRequestType = USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE;
+ dr->wValue = 0;
+ dr->wIndex = 0;
+ dr->wLength = cpu_to_le16(size);
+
+ usb_fill_control_urb(urb, udev, usb_sndctrlpipe(udev, 0),
+ (unsigned char *)dr, buf, size,
+ ap_urb_complete, dr);
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval) {
+ usb_free_urb(urb);
+ kfree(dr);
+ }
+ return retval;
+}
+
+static int output(struct gb_host_device *hd, void *req, u16 size, u8 cmd,
+ bool async)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+
+ if (async)
+ return output_async(es2, req, size, cmd);
+
+ return output_sync(es2, req, size, cmd);
+}
+
+static int es2_cport_in_enable(struct es2_ap_dev *es2,
+ struct es2_cport_in *cport_in)
+{
+ struct urb *urb;
+ int ret;
+ int i;
+
+ for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
+ urb = cport_in->urb[i];
+
+ ret = usb_submit_urb(urb, GFP_KERNEL);
+ if (ret) {
+ dev_err(&es2->usb_dev->dev,
+ "failed to submit in-urb: %d\n", ret);
+ goto err_kill_urbs;
+ }
+ }
+
+ return 0;
+
+err_kill_urbs:
+ for (--i; i >= 0; --i) {
+ urb = cport_in->urb[i];
+ usb_kill_urb(urb);
+ }
+
+ return ret;
+}
+
+static void es2_cport_in_disable(struct es2_ap_dev *es2,
+ struct es2_cport_in *cport_in)
+{
+ struct urb *urb;
+ int i;
+
+ for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
+ urb = cport_in->urb[i];
+ usb_kill_urb(urb);
+ }
+}
+
+static int es2_arpc_in_enable(struct es2_ap_dev *es2)
+{
+ struct urb *urb;
+ int ret;
+ int i;
+
+ for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
+ urb = es2->arpc_urb[i];
+
+ ret = usb_submit_urb(urb, GFP_KERNEL);
+ if (ret) {
+ dev_err(&es2->usb_dev->dev,
+ "failed to submit arpc in-urb: %d\n", ret);
+ goto err_kill_urbs;
+ }
+ }
+
+ return 0;
+
+err_kill_urbs:
+ for (--i; i >= 0; --i) {
+ urb = es2->arpc_urb[i];
+ usb_kill_urb(urb);
+ }
+
+ return ret;
+}
+
+static void es2_arpc_in_disable(struct es2_ap_dev *es2)
+{
+ struct urb *urb;
+ int i;
+
+ for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
+ urb = es2->arpc_urb[i];
+ usb_kill_urb(urb);
+ }
+}
+
+static struct urb *next_free_urb(struct es2_ap_dev *es2, gfp_t gfp_mask)
+{
+ struct urb *urb = NULL;
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
+
+ /* Look in our pool of allocated urbs first, as that's the "fastest" */
+ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
+ if (!es2->cport_out_urb_busy[i] &&
+ !es2->cport_out_urb_cancelled[i]) {
+ es2->cport_out_urb_busy[i] = true;
+ urb = es2->cport_out_urb[i];
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
+ if (urb)
+ return urb;
+
+ /*
+ * Crap, pool is empty, complain to the syslog and go allocate one
+ * dynamically as we have to succeed.
+ */
+ dev_dbg(&es2->usb_dev->dev,
+ "No free CPort OUT urbs, having to dynamically allocate one!\n");
+ return usb_alloc_urb(0, gfp_mask);
+}
+
+static void free_urb(struct es2_ap_dev *es2, struct urb *urb)
+{
+ unsigned long flags;
+ int i;
+ /*
+ * See if this was an urb in our pool, if so mark it "free", otherwise
+ * we need to free it ourselves.
+ */
+ spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
+ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
+ if (urb == es2->cport_out_urb[i]) {
+ es2->cport_out_urb_busy[i] = false;
+ urb = NULL;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
+
+ /* If urb is not NULL, then we need to free this urb */
+ usb_free_urb(urb);
+}
+
+/*
+ * We (ab)use the operation-message header pad bytes to transfer the
+ * cport id in order to minimise overhead.
+ */
+static void
+gb_message_cport_pack(struct gb_operation_msg_hdr *header, u16 cport_id)
+{
+ header->pad[0] = cport_id;
+}
+
+/* Clear the pad bytes used for the CPort id */
+static void gb_message_cport_clear(struct gb_operation_msg_hdr *header)
+{
+ header->pad[0] = 0;
+}
+
+/* Extract the CPort id packed into the header, and clear it */
+static u16 gb_message_cport_unpack(struct gb_operation_msg_hdr *header)
+{
+ u16 cport_id = header->pad[0];
+
+ gb_message_cport_clear(header);
+
+ return cport_id;
+}
+
+/*
+ * Returns zero if the message was successfully queued, or a negative errno
+ * otherwise.
+ */
+static int message_send(struct gb_host_device *hd, u16 cport_id,
+ struct gb_message *message, gfp_t gfp_mask)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct usb_device *udev = es2->usb_dev;
+ size_t buffer_size;
+ int retval;
+ struct urb *urb;
+ unsigned long flags;
+
+ /*
+ * The data actually transferred will include an indication
+ * of where the data should be sent. Do one last check of
+ * the target CPort id before filling it in.
+ */
+ if (!cport_id_valid(hd, cport_id)) {
+ dev_err(&udev->dev, "invalid cport %u\n", cport_id);
+ return -EINVAL;
+ }
+
+ /* Find a free urb */
+ urb = next_free_urb(es2, gfp_mask);
+ if (!urb)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
+ message->hcpriv = urb;
+ spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
+
+ /* Pack the cport id into the message header */
+ gb_message_cport_pack(message->header, cport_id);
+
+ buffer_size = sizeof(*message->header) + message->payload_size;
+
+ usb_fill_bulk_urb(urb, udev,
+ usb_sndbulkpipe(udev,
+ es2->cport_out_endpoint),
+ message->buffer, buffer_size,
+ cport_out_callback, message);
+ urb->transfer_flags |= URB_ZERO_PACKET;
+
+ trace_gb_message_submit(message);
+
+ retval = usb_submit_urb(urb, gfp_mask);
+ if (retval) {
+ dev_err(&udev->dev, "failed to submit out-urb: %d\n", retval);
+
+ spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
+ message->hcpriv = NULL;
+ spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
+
+ free_urb(es2, urb);
+ gb_message_cport_clear(message->header);
+
+ return retval;
+ }
+
+ return 0;
+}
+
+/*
+ * Can not be called in atomic context.
+ */
+static void message_cancel(struct gb_message *message)
+{
+ struct gb_host_device *hd = message->operation->connection->hd;
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct urb *urb;
+ int i;
+
+ might_sleep();
+
+ spin_lock_irq(&es2->cport_out_urb_lock);
+ urb = message->hcpriv;
+
+ /* Prevent dynamically allocated urb from being deallocated. */
+ usb_get_urb(urb);
+
+ /* Prevent pre-allocated urb from being reused. */
+ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
+ if (urb == es2->cport_out_urb[i]) {
+ es2->cport_out_urb_cancelled[i] = true;
+ break;
+ }
+ }
+ spin_unlock_irq(&es2->cport_out_urb_lock);
+
+ usb_kill_urb(urb);
+
+ if (i < NUM_CPORT_OUT_URB) {
+ spin_lock_irq(&es2->cport_out_urb_lock);
+ es2->cport_out_urb_cancelled[i] = false;
+ spin_unlock_irq(&es2->cport_out_urb_lock);
+ }
+
+ usb_free_urb(urb);
+}
+
+static int es2_cport_allocate(struct gb_host_device *hd, int cport_id,
+ unsigned long flags)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct ida *id_map = &hd->cport_id_map;
+ int ida_start, ida_end;
+
+ switch (cport_id) {
+ case ES2_CPORT_CDSI0:
+ case ES2_CPORT_CDSI1:
+ dev_err(&hd->dev, "cport %d not available\n", cport_id);
+ return -EBUSY;
+ }
+
+ if (flags & GB_CONNECTION_FLAG_OFFLOADED &&
+ flags & GB_CONNECTION_FLAG_CDSI1) {
+ if (es2->cdsi1_in_use) {
+ dev_err(&hd->dev, "CDSI1 already in use\n");
+ return -EBUSY;
+ }
+
+ es2->cdsi1_in_use = true;
+
+ return ES2_CPORT_CDSI1;
+ }
+
+ if (cport_id < 0) {
+ ida_start = 0;
+ ida_end = hd->num_cports;
+ } else if (cport_id < hd->num_cports) {
+ ida_start = cport_id;
+ ida_end = cport_id + 1;
+ } else {
+ dev_err(&hd->dev, "cport %d not available\n", cport_id);
+ return -EINVAL;
+ }
+
+ return ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL);
+}
+
+static void es2_cport_release(struct gb_host_device *hd, u16 cport_id)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+
+ switch (cport_id) {
+ case ES2_CPORT_CDSI1:
+ es2->cdsi1_in_use = false;
+ return;
+ }
+
+ ida_simple_remove(&hd->cport_id_map, cport_id);
+}
+
+static int cport_enable(struct gb_host_device *hd, u16 cport_id,
+ unsigned long flags)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct usb_device *udev = es2->usb_dev;
+ struct gb_apb_request_cport_flags *req;
+ u32 connection_flags;
+ int ret;
+
+ req = kzalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ connection_flags = 0;
+ if (flags & GB_CONNECTION_FLAG_CONTROL)
+ connection_flags |= GB_APB_CPORT_FLAG_CONTROL;
+ if (flags & GB_CONNECTION_FLAG_HIGH_PRIO)
+ connection_flags |= GB_APB_CPORT_FLAG_HIGH_PRIO;
+
+ req->flags = cpu_to_le32(connection_flags);
+
+ dev_dbg(&hd->dev, "%s - cport = %u, flags = %02x\n", __func__,
+ cport_id, connection_flags);
+
+ ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ GB_APB_REQUEST_CPORT_FLAGS,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE, cport_id, 0,
+ req, sizeof(*req), ES2_USB_CTRL_TIMEOUT);
+ if (ret < 0) {
+ dev_err(&udev->dev, "failed to set cport flags for port %d\n",
+ cport_id);
+ goto out;
+ }
+
+ ret = 0;
+out:
+ kfree(req);
+
+ return ret;
+}
+
+static int es2_cport_connected(struct gb_host_device *hd, u16 cport_id)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct device *dev = &es2->usb_dev->dev;
+ struct arpc_cport_connected_req req;
+ int ret;
+
+ req.cport_id = cpu_to_le16(cport_id);
+ ret = arpc_sync(es2, ARPC_TYPE_CPORT_CONNECTED, &req, sizeof(req),
+ NULL, ES2_ARPC_CPORT_TIMEOUT);
+ if (ret) {
+ dev_err(dev, "failed to set connected state for cport %u: %d\n",
+ cport_id, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int es2_cport_flush(struct gb_host_device *hd, u16 cport_id)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct device *dev = &es2->usb_dev->dev;
+ struct arpc_cport_flush_req req;
+ int ret;
+
+ req.cport_id = cpu_to_le16(cport_id);
+ ret = arpc_sync(es2, ARPC_TYPE_CPORT_FLUSH, &req, sizeof(req),
+ NULL, ES2_ARPC_CPORT_TIMEOUT);
+ if (ret) {
+ dev_err(dev, "failed to flush cport %u: %d\n", cport_id, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int es2_cport_shutdown(struct gb_host_device *hd, u16 cport_id,
+ u8 phase, unsigned int timeout)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct device *dev = &es2->usb_dev->dev;
+ struct arpc_cport_shutdown_req req;
+ int result;
+ int ret;
+
+ if (timeout > U16_MAX)
+ return -EINVAL;
+
+ req.cport_id = cpu_to_le16(cport_id);
+ req.timeout = cpu_to_le16(timeout);
+ req.phase = phase;
+ ret = arpc_sync(es2, ARPC_TYPE_CPORT_SHUTDOWN, &req, sizeof(req),
+ &result, ES2_ARPC_CPORT_TIMEOUT + timeout);
+ if (ret) {
+ dev_err(dev, "failed to send shutdown over cport %u: %d (%d)\n",
+ cport_id, ret, result);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int es2_cport_quiesce(struct gb_host_device *hd, u16 cport_id,
+ size_t peer_space, unsigned int timeout)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct device *dev = &es2->usb_dev->dev;
+ struct arpc_cport_quiesce_req req;
+ int result;
+ int ret;
+
+ if (peer_space > U16_MAX)
+ return -EINVAL;
+
+ if (timeout > U16_MAX)
+ return -EINVAL;
+
+ req.cport_id = cpu_to_le16(cport_id);
+ req.peer_space = cpu_to_le16(peer_space);
+ req.timeout = cpu_to_le16(timeout);
+ ret = arpc_sync(es2, ARPC_TYPE_CPORT_QUIESCE, &req, sizeof(req),
+ &result, ES2_ARPC_CPORT_TIMEOUT + timeout);
+ if (ret) {
+ dev_err(dev, "failed to quiesce cport %u: %d (%d)\n",
+ cport_id, ret, result);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int es2_cport_clear(struct gb_host_device *hd, u16 cport_id)
+{
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct device *dev = &es2->usb_dev->dev;
+ struct arpc_cport_clear_req req;
+ int ret;
+
+ req.cport_id = cpu_to_le16(cport_id);
+ ret = arpc_sync(es2, ARPC_TYPE_CPORT_CLEAR, &req, sizeof(req),
+ NULL, ES2_ARPC_CPORT_TIMEOUT);
+ if (ret) {
+ dev_err(dev, "failed to clear cport %u: %d\n", cport_id, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int latency_tag_enable(struct gb_host_device *hd, u16 cport_id)
+{
+ int retval;
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct usb_device *udev = es2->usb_dev;
+
+ retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ GB_APB_REQUEST_LATENCY_TAG_EN,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE, cport_id, 0, NULL,
+ 0, ES2_USB_CTRL_TIMEOUT);
+
+ if (retval < 0)
+ dev_err(&udev->dev, "Cannot enable latency tag for cport %d\n",
+ cport_id);
+ return retval;
+}
+
+static int latency_tag_disable(struct gb_host_device *hd, u16 cport_id)
+{
+ int retval;
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ struct usb_device *udev = es2->usb_dev;
+
+ retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ GB_APB_REQUEST_LATENCY_TAG_DIS,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE, cport_id, 0, NULL,
+ 0, ES2_USB_CTRL_TIMEOUT);
+
+ if (retval < 0)
+ dev_err(&udev->dev, "Cannot disable latency tag for cport %d\n",
+ cport_id);
+ return retval;
+}
+
+static struct gb_hd_driver es2_driver = {
+ .hd_priv_size = sizeof(struct es2_ap_dev),
+ .message_send = message_send,
+ .message_cancel = message_cancel,
+ .cport_allocate = es2_cport_allocate,
+ .cport_release = es2_cport_release,
+ .cport_enable = cport_enable,
+ .cport_connected = es2_cport_connected,
+ .cport_flush = es2_cport_flush,
+ .cport_shutdown = es2_cport_shutdown,
+ .cport_quiesce = es2_cport_quiesce,
+ .cport_clear = es2_cport_clear,
+ .latency_tag_enable = latency_tag_enable,
+ .latency_tag_disable = latency_tag_disable,
+ .output = output,
+};
+
+/* Common function to report consistent warnings based on URB status */
+static int check_urb_status(struct urb *urb)
+{
+ struct device *dev = &urb->dev->dev;
+ int status = urb->status;
+
+ switch (status) {
+ case 0:
+ return 0;
+
+ case -EOVERFLOW:
+ dev_err(dev, "%s: overflow actual length is %d\n",
+ __func__, urb->actual_length);
+ fallthrough;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ case -EILSEQ:
+ case -EPROTO:
+ /* device is gone, stop sending */
+ return status;
+ }
+ dev_err(dev, "%s: unknown status %d\n", __func__, status);
+
+ return -EAGAIN;
+}
+
+static void es2_destroy(struct es2_ap_dev *es2)
+{
+ struct usb_device *udev;
+ struct urb *urb;
+ int i;
+
+ debugfs_remove(es2->apb_log_enable_dentry);
+ usb_log_disable(es2);
+
+ /* Tear down everything! */
+ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
+ urb = es2->cport_out_urb[i];
+ usb_kill_urb(urb);
+ usb_free_urb(urb);
+ es2->cport_out_urb[i] = NULL;
+ es2->cport_out_urb_busy[i] = false; /* just to be anal */
+ }
+
+ for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
+ usb_free_urb(es2->arpc_urb[i]);
+ kfree(es2->arpc_buffer[i]);
+ es2->arpc_buffer[i] = NULL;
+ }
+
+ for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
+ usb_free_urb(es2->cport_in.urb[i]);
+ kfree(es2->cport_in.buffer[i]);
+ es2->cport_in.buffer[i] = NULL;
+ }
+
+ /* release reserved CDSI0 and CDSI1 cports */
+ gb_hd_cport_release_reserved(es2->hd, ES2_CPORT_CDSI1);
+ gb_hd_cport_release_reserved(es2->hd, ES2_CPORT_CDSI0);
+
+ udev = es2->usb_dev;
+ gb_hd_put(es2->hd);
+
+ usb_put_dev(udev);
+}
+
+static void cport_in_callback(struct urb *urb)
+{
+ struct gb_host_device *hd = urb->context;
+ struct device *dev = &urb->dev->dev;
+ struct gb_operation_msg_hdr *header;
+ int status = check_urb_status(urb);
+ int retval;
+ u16 cport_id;
+
+ if (status) {
+ if ((status == -EAGAIN) || (status == -EPROTO))
+ goto exit;
+
+ /* The urb is being unlinked */
+ if (status == -ENOENT || status == -ESHUTDOWN)
+ return;
+
+ dev_err(dev, "urb cport in error %d (dropped)\n", status);
+ return;
+ }
+
+ if (urb->actual_length < sizeof(*header)) {
+ dev_err(dev, "short message received\n");
+ goto exit;
+ }
+
+ /* Extract the CPort id, which is packed in the message header */
+ header = urb->transfer_buffer;
+ cport_id = gb_message_cport_unpack(header);
+
+ if (cport_id_valid(hd, cport_id)) {
+ greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
+ urb->actual_length);
+ } else {
+ dev_err(dev, "invalid cport id %u received\n", cport_id);
+ }
+exit:
+ /* put our urb back in the request pool */
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval)
+ dev_err(dev, "failed to resubmit in-urb: %d\n", retval);
+}
+
+static void cport_out_callback(struct urb *urb)
+{
+ struct gb_message *message = urb->context;
+ struct gb_host_device *hd = message->operation->connection->hd;
+ struct es2_ap_dev *es2 = hd_to_es2(hd);
+ int status = check_urb_status(urb);
+ unsigned long flags;
+
+ gb_message_cport_clear(message->header);
+
+ spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
+ message->hcpriv = NULL;
+ spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
+
+ /*
+ * Tell the submitter that the message send (attempt) is
+ * complete, and report the status.
+ */
+ greybus_message_sent(hd, message, status);
+
+ free_urb(es2, urb);
+}
+
+static struct arpc *arpc_alloc(void *payload, u16 size, u8 type)
+{
+ struct arpc *rpc;
+
+ if (size + sizeof(*rpc->req) > ARPC_OUT_SIZE_MAX)
+ return NULL;
+
+ rpc = kzalloc(sizeof(*rpc), GFP_KERNEL);
+ if (!rpc)
+ return NULL;
+
+ INIT_LIST_HEAD(&rpc->list);
+ rpc->req = kzalloc(sizeof(*rpc->req) + size, GFP_KERNEL);
+ if (!rpc->req)
+ goto err_free_rpc;
+
+ rpc->resp = kzalloc(sizeof(*rpc->resp), GFP_KERNEL);
+ if (!rpc->resp)
+ goto err_free_req;
+
+ rpc->req->type = type;
+ rpc->req->size = cpu_to_le16(sizeof(*rpc->req) + size);
+ memcpy(rpc->req->data, payload, size);
+
+ init_completion(&rpc->response_received);
+
+ return rpc;
+
+err_free_req:
+ kfree(rpc->req);
+err_free_rpc:
+ kfree(rpc);
+
+ return NULL;
+}
+
+static void arpc_free(struct arpc *rpc)
+{
+ kfree(rpc->req);
+ kfree(rpc->resp);
+ kfree(rpc);
+}
+
+static struct arpc *arpc_find(struct es2_ap_dev *es2, __le16 id)
+{
+ struct arpc *rpc;
+
+ list_for_each_entry(rpc, &es2->arpcs, list) {
+ if (rpc->req->id == id)
+ return rpc;
+ }
+
+ return NULL;
+}
+
+static void arpc_add(struct es2_ap_dev *es2, struct arpc *rpc)
+{
+ rpc->active = true;
+ rpc->req->id = cpu_to_le16(es2->arpc_id_cycle++);
+ list_add_tail(&rpc->list, &es2->arpcs);
+}
+
+static void arpc_del(struct es2_ap_dev *es2, struct arpc *rpc)
+{
+ if (rpc->active) {
+ rpc->active = false;
+ list_del(&rpc->list);
+ }
+}
+
+static int arpc_send(struct es2_ap_dev *es2, struct arpc *rpc, int timeout)
+{
+ struct usb_device *udev = es2->usb_dev;
+ int retval;
+
+ retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ GB_APB_REQUEST_ARPC_RUN,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE,
+ 0, 0,
+ rpc->req, le16_to_cpu(rpc->req->size),
+ ES2_USB_CTRL_TIMEOUT);
+ if (retval < 0) {
+ dev_err(&udev->dev,
+ "failed to send ARPC request %d: %d\n",
+ rpc->req->type, retval);
+ return retval;
+ }
+
+ return 0;
+}
+
+static int arpc_sync(struct es2_ap_dev *es2, u8 type, void *payload,
+ size_t size, int *result, unsigned int timeout)
+{
+ struct arpc *rpc;
+ unsigned long flags;
+ int retval;
+
+ if (result)
+ *result = 0;
+
+ rpc = arpc_alloc(payload, size, type);
+ if (!rpc)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&es2->arpc_lock, flags);
+ arpc_add(es2, rpc);
+ spin_unlock_irqrestore(&es2->arpc_lock, flags);
+
+ retval = arpc_send(es2, rpc, timeout);
+ if (retval)
+ goto out_arpc_del;
+
+ retval = wait_for_completion_interruptible_timeout(
+ &rpc->response_received,
+ msecs_to_jiffies(timeout));
+ if (retval <= 0) {
+ if (!retval)
+ retval = -ETIMEDOUT;
+ goto out_arpc_del;
+ }
+
+ if (rpc->resp->result) {
+ retval = -EREMOTEIO;
+ if (result)
+ *result = rpc->resp->result;
+ } else {
+ retval = 0;
+ }
+
+out_arpc_del:
+ spin_lock_irqsave(&es2->arpc_lock, flags);
+ arpc_del(es2, rpc);
+ spin_unlock_irqrestore(&es2->arpc_lock, flags);
+ arpc_free(rpc);
+
+ if (retval < 0 && retval != -EREMOTEIO) {
+ dev_err(&es2->usb_dev->dev,
+ "failed to execute ARPC: %d\n", retval);
+ }
+
+ return retval;
+}
+
+static void arpc_in_callback(struct urb *urb)
+{
+ struct es2_ap_dev *es2 = urb->context;
+ struct device *dev = &urb->dev->dev;
+ int status = check_urb_status(urb);
+ struct arpc *rpc;
+ struct arpc_response_message *resp;
+ unsigned long flags;
+ int retval;
+
+ if (status) {
+ if ((status == -EAGAIN) || (status == -EPROTO))
+ goto exit;
+
+ /* The urb is being unlinked */
+ if (status == -ENOENT || status == -ESHUTDOWN)
+ return;
+
+ dev_err(dev, "arpc in-urb error %d (dropped)\n", status);
+ return;
+ }
+
+ if (urb->actual_length < sizeof(*resp)) {
+ dev_err(dev, "short aprc response received\n");
+ goto exit;
+ }
+
+ resp = urb->transfer_buffer;
+ spin_lock_irqsave(&es2->arpc_lock, flags);
+ rpc = arpc_find(es2, resp->id);
+ if (!rpc) {
+ dev_err(dev, "invalid arpc response id received: %u\n",
+ le16_to_cpu(resp->id));
+ spin_unlock_irqrestore(&es2->arpc_lock, flags);
+ goto exit;
+ }
+
+ arpc_del(es2, rpc);
+ memcpy(rpc->resp, resp, sizeof(*resp));
+ complete(&rpc->response_received);
+ spin_unlock_irqrestore(&es2->arpc_lock, flags);
+
+exit:
+ /* put our urb back in the request pool */
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval)
+ dev_err(dev, "failed to resubmit arpc in-urb: %d\n", retval);
+}
+
+#define APB1_LOG_MSG_SIZE 64
+static void apb_log_get(struct es2_ap_dev *es2, char *buf)
+{
+ int retval;
+
+ do {
+ retval = usb_control_msg(es2->usb_dev,
+ usb_rcvctrlpipe(es2->usb_dev, 0),
+ GB_APB_REQUEST_LOG,
+ USB_DIR_IN | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE,
+ 0x00, 0x00,
+ buf,
+ APB1_LOG_MSG_SIZE,
+ ES2_USB_CTRL_TIMEOUT);
+ if (retval > 0)
+ kfifo_in(&es2->apb_log_fifo, buf, retval);
+ } while (retval > 0);
+}
+
+static int apb_log_poll(void *data)
+{
+ struct es2_ap_dev *es2 = data;
+ char *buf;
+
+ buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ while (!kthread_should_stop()) {
+ msleep(1000);
+ apb_log_get(es2, buf);
+ }
+
+ kfree(buf);
+
+ return 0;
+}
+
+static ssize_t apb_log_read(struct file *f, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct es2_ap_dev *es2 = file_inode(f)->i_private;
+ ssize_t ret;
+ size_t copied;
+ char *tmp_buf;
+
+ if (count > APB1_LOG_SIZE)
+ count = APB1_LOG_SIZE;
+
+ tmp_buf = kmalloc(count, GFP_KERNEL);
+ if (!tmp_buf)
+ return -ENOMEM;
+
+ copied = kfifo_out(&es2->apb_log_fifo, tmp_buf, count);
+ ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied);
+
+ kfree(tmp_buf);
+
+ return ret;
+}
+
+static const struct file_operations apb_log_fops = {
+ .read = apb_log_read,
+};
+
+static void usb_log_enable(struct es2_ap_dev *es2)
+{
+ if (!IS_ERR_OR_NULL(es2->apb_log_task))
+ return;
+
+ /* get log from APB1 */
+ es2->apb_log_task = kthread_run(apb_log_poll, es2, "apb_log");
+ if (IS_ERR(es2->apb_log_task))
+ return;
+ /* XXX We will need to rename this per APB */
+ es2->apb_log_dentry = debugfs_create_file("apb_log", 0444,
+ gb_debugfs_get(), es2,
+ &apb_log_fops);
+}
+
+static void usb_log_disable(struct es2_ap_dev *es2)
+{
+ if (IS_ERR_OR_NULL(es2->apb_log_task))
+ return;
+
+ debugfs_remove(es2->apb_log_dentry);
+ es2->apb_log_dentry = NULL;
+
+ kthread_stop(es2->apb_log_task);
+ es2->apb_log_task = NULL;
+}
+
+static ssize_t apb_log_enable_read(struct file *f, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct es2_ap_dev *es2 = file_inode(f)->i_private;
+ int enable = !IS_ERR_OR_NULL(es2->apb_log_task);
+ char tmp_buf[3];
+
+ sprintf(tmp_buf, "%d\n", enable);
+ return simple_read_from_buffer(buf, count, ppos, tmp_buf, 2);
+}
+
+static ssize_t apb_log_enable_write(struct file *f, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ int enable;
+ ssize_t retval;
+ struct es2_ap_dev *es2 = file_inode(f)->i_private;
+
+ retval = kstrtoint_from_user(buf, count, 10, &enable);
+ if (retval)
+ return retval;
+
+ if (enable)
+ usb_log_enable(es2);
+ else
+ usb_log_disable(es2);
+
+ return count;
+}
+
+static const struct file_operations apb_log_enable_fops = {
+ .read = apb_log_enable_read,
+ .write = apb_log_enable_write,
+};
+
+static int apb_get_cport_count(struct usb_device *udev)
+{
+ int retval;
+ __le16 *cport_count;
+
+ cport_count = kzalloc(sizeof(*cport_count), GFP_KERNEL);
+ if (!cport_count)
+ return -ENOMEM;
+
+ retval = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+ GB_APB_REQUEST_CPORT_COUNT,
+ USB_DIR_IN | USB_TYPE_VENDOR |
+ USB_RECIP_INTERFACE, 0, 0, cport_count,
+ sizeof(*cport_count), ES2_USB_CTRL_TIMEOUT);
+ if (retval != sizeof(*cport_count)) {
+ dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
+ retval);
+
+ if (retval >= 0)
+ retval = -EIO;
+
+ goto out;
+ }
+
+ retval = le16_to_cpu(*cport_count);
+
+ /* We need to fit a CPort ID in one byte of a message header */
+ if (retval > U8_MAX) {
+ retval = U8_MAX;
+ dev_warn(&udev->dev, "Limiting number of CPorts to U8_MAX\n");
+ }
+
+out:
+ kfree(cport_count);
+ return retval;
+}
+
+/*
+ * The ES2 USB Bridge device has 15 endpoints
+ * 1 Control - usual USB stuff + AP -> APBridgeA messages
+ * 7 Bulk IN - CPort data in
+ * 7 Bulk OUT - CPort data out
+ */
+static int ap_probe(struct usb_interface *interface,
+ const struct usb_device_id *id)
+{
+ struct es2_ap_dev *es2;
+ struct gb_host_device *hd;
+ struct usb_device *udev;
+ struct usb_host_interface *iface_desc;
+ struct usb_endpoint_descriptor *endpoint;
+ __u8 ep_addr;
+ int retval;
+ int i;
+ int num_cports;
+ bool bulk_out_found = false;
+ bool bulk_in_found = false;
+ bool arpc_in_found = false;
+
+ udev = usb_get_dev(interface_to_usbdev(interface));
+
+ num_cports = apb_get_cport_count(udev);
+ if (num_cports < 0) {
+ usb_put_dev(udev);
+ dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
+ num_cports);
+ return num_cports;
+ }
+
+ hd = gb_hd_create(&es2_driver, &udev->dev, ES2_GBUF_MSG_SIZE_MAX,
+ num_cports);
+ if (IS_ERR(hd)) {
+ usb_put_dev(udev);
+ return PTR_ERR(hd);
+ }
+
+ es2 = hd_to_es2(hd);
+ es2->hd = hd;
+ es2->usb_intf = interface;
+ es2->usb_dev = udev;
+ spin_lock_init(&es2->cport_out_urb_lock);
+ INIT_KFIFO(es2->apb_log_fifo);
+ usb_set_intfdata(interface, es2);
+
+ /*
+ * Reserve the CDSI0 and CDSI1 CPorts so they won't be allocated
+ * dynamically.
+ */
+ retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI0);
+ if (retval)
+ goto error;
+ retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI1);
+ if (retval)
+ goto error;
+
+ /* find all bulk endpoints */
+ iface_desc = interface->cur_altsetting;
+ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+ endpoint = &iface_desc->endpoint[i].desc;
+ ep_addr = endpoint->bEndpointAddress;
+
+ if (usb_endpoint_is_bulk_in(endpoint)) {
+ if (!bulk_in_found) {
+ es2->cport_in.endpoint = ep_addr;
+ bulk_in_found = true;
+ } else if (!arpc_in_found) {
+ es2->arpc_endpoint_in = ep_addr;
+ arpc_in_found = true;
+ } else {
+ dev_warn(&udev->dev,
+ "Unused bulk IN endpoint found: 0x%02x\n",
+ ep_addr);
+ }
+ continue;
+ }
+ if (usb_endpoint_is_bulk_out(endpoint)) {
+ if (!bulk_out_found) {
+ es2->cport_out_endpoint = ep_addr;
+ bulk_out_found = true;
+ } else {
+ dev_warn(&udev->dev,
+ "Unused bulk OUT endpoint found: 0x%02x\n",
+ ep_addr);
+ }
+ continue;
+ }
+ dev_warn(&udev->dev,
+ "Unknown endpoint type found, address 0x%02x\n",
+ ep_addr);
+ }
+ if (!bulk_in_found || !arpc_in_found || !bulk_out_found) {
+ dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
+ retval = -ENODEV;
+ goto error;
+ }
+
+ /* Allocate buffers for our cport in messages */
+ for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
+ struct urb *urb;
+ u8 *buffer;
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ retval = -ENOMEM;
+ goto error;
+ }
+ es2->cport_in.urb[i] = urb;
+
+ buffer = kmalloc(ES2_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
+ if (!buffer) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ usb_fill_bulk_urb(urb, udev,
+ usb_rcvbulkpipe(udev, es2->cport_in.endpoint),
+ buffer, ES2_GBUF_MSG_SIZE_MAX,
+ cport_in_callback, hd);
+
+ es2->cport_in.buffer[i] = buffer;
+ }
+
+ /* Allocate buffers for ARPC in messages */
+ for (i = 0; i < NUM_ARPC_IN_URB; ++i) {
+ struct urb *urb;
+ u8 *buffer;
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ retval = -ENOMEM;
+ goto error;
+ }
+ es2->arpc_urb[i] = urb;
+
+ buffer = kmalloc(ARPC_IN_SIZE_MAX, GFP_KERNEL);
+ if (!buffer) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ usb_fill_bulk_urb(urb, udev,
+ usb_rcvbulkpipe(udev,
+ es2->arpc_endpoint_in),
+ buffer, ARPC_IN_SIZE_MAX,
+ arpc_in_callback, es2);
+
+ es2->arpc_buffer[i] = buffer;
+ }
+
+ /* Allocate urbs for our CPort OUT messages */
+ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
+ struct urb *urb;
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ es2->cport_out_urb[i] = urb;
+ es2->cport_out_urb_busy[i] = false; /* just to be anal */
+ }
+
+ /* XXX We will need to rename this per APB */
+ es2->apb_log_enable_dentry = debugfs_create_file("apb_log_enable",
+ 0644,
+ gb_debugfs_get(), es2,
+ &apb_log_enable_fops);
+
+ INIT_LIST_HEAD(&es2->arpcs);
+ spin_lock_init(&es2->arpc_lock);
+
+ retval = es2_arpc_in_enable(es2);
+ if (retval)
+ goto error;
+
+ retval = gb_hd_add(hd);
+ if (retval)
+ goto err_disable_arpc_in;
+
+ retval = es2_cport_in_enable(es2, &es2->cport_in);
+ if (retval)
+ goto err_hd_del;
+
+ return 0;
+
+err_hd_del:
+ gb_hd_del(hd);
+err_disable_arpc_in:
+ es2_arpc_in_disable(es2);
+error:
+ es2_destroy(es2);
+
+ return retval;
+}
+
+static void ap_disconnect(struct usb_interface *interface)
+{
+ struct es2_ap_dev *es2 = usb_get_intfdata(interface);
+
+ gb_hd_del(es2->hd);
+
+ es2_cport_in_disable(es2, &es2->cport_in);
+ es2_arpc_in_disable(es2);
+
+ es2_destroy(es2);
+}
+
+static struct usb_driver es2_ap_driver = {
+ .name = "es2_ap_driver",
+ .probe = ap_probe,
+ .disconnect = ap_disconnect,
+ .id_table = id_table,
+ .soft_unbind = 1,
+};
+
+module_usb_driver(es2_ap_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");