Merge tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here's the big char/misc driver patchset for 4.1-rc1.

  Lots of different driver subsystem updates here, nothing major, full
  details are in the shortlog.

  All of this has been in linux-next for a while"

* tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (133 commits)
  mei: trace: remove unused TRACE_SYSTEM_STRING
  DTS: ARM: OMAP3-N900: Add lis3lv02d support
  Documentation: DT: lis302: update wakeup binding
  lis3lv02d: DT: add wakeup unit 2 and wakeup threshold
  lis3lv02d: DT: use s32 to support negative values
  Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case
  Drivers: hv: hv_balloon: correctly handle val.freeram<num_pages case
  mei: replace check for connection instead of transitioning
  mei: use mei_cl_is_connected consistently
  mei: fix mei_poll operation
  hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()
  Drivers: hv: hv_balloon: survive ballooning request with num_pages=0
  Drivers: hv: hv_balloon: eliminate jumps in piecewiese linear floor function
  Drivers: hv: hv_balloon: do not online pages in offline blocks
  hv: remove the per-channel workqueue
  hv: don't schedule new works in vmbus_onoffer()/vmbus_onoffer_rescind()
  hv: run non-blocking message handlers in the dispatch tasklet
  coresight: moving to new "hwtracing" directory
  coresight-tmc: Adding a status interface to sysfs
  coresight: remove the unnecessary configuration coresight-default-sink
  ...

20 files changed, 935 insertions, 866 deletions

diff --git a/drivers/misc/mei/Makefile b/drivers/misc/mei/Makefile
index 8ebc6cda1373..518914a82b83 100644
--- a/drivers/misc/mei/Makefile
+++ b/drivers/misc/mei/Makefile
@@ -21,3 +21,6 @@ mei-me-objs += hw-me.o
 obj-$(CONFIG_INTEL_MEI_TXE) += mei-txe.o
 mei-txe-objs := pci-txe.o
 mei-txe-objs += hw-txe.o
+
+mei-$(CONFIG_EVENT_TRACING) += mei-trace.o
+CFLAGS_mei-trace.o = -I$(src)
diff --git a/drivers/misc/mei/amthif.c b/drivers/misc/mei/amthif.c
index 40ea639fa413..d2cd53e3fac3 100644
--- a/drivers/misc/mei/amthif.c
+++ b/drivers/misc/mei/amthif.c
@@ -48,10 +48,7 @@ void mei_amthif_reset_params(struct mei_device *dev)
 {
 	/* reset iamthif parameters. */
 	dev->iamthif_current_cb = NULL;
-	dev->iamthif_msg_buf_size = 0;
-	dev->iamthif_msg_buf_index = 0;
 	dev->iamthif_canceled = false;
-	dev->iamthif_ioctl = false;
 	dev->iamthif_state = MEI_IAMTHIF_IDLE;
 	dev->iamthif_timer = 0;
 	dev->iamthif_stall_timer = 0;
@@ -69,7 +66,6 @@ int mei_amthif_host_init(struct mei_device *dev)
 {
 	struct mei_cl *cl = &dev->iamthif_cl;
 	struct mei_me_client *me_cl;
-	unsigned char *msg_buf;
 	int ret;
 
 	dev->iamthif_state = MEI_IAMTHIF_IDLE;
@@ -90,18 +86,6 @@ int mei_amthif_host_init(struct mei_device *dev)
 	dev->iamthif_mtu = me_cl->props.max_msg_length;
 	dev_dbg(dev->dev, "IAMTHIF_MTU = %d\n", dev->iamthif_mtu);
 
-	kfree(dev->iamthif_msg_buf);
-	dev->iamthif_msg_buf = NULL;
-
-	/* allocate storage for ME message buffer */
-	msg_buf = kcalloc(dev->iamthif_mtu,
-			sizeof(unsigned char), GFP_KERNEL);
-	if (!msg_buf) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	dev->iamthif_msg_buf = msg_buf;
 
 	ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
 	if (ret < 0) {
@@ -194,30 +178,33 @@ int mei_amthif_read(struct mei_device *dev, struct file *file,
 		dev_dbg(dev->dev, "woke up from sleep\n");
 	}
 
+	if (cb->status) {
+		rets = cb->status;
+		dev_dbg(dev->dev, "read operation failed %d\n", rets);
+		goto free;
+	}
 
 	dev_dbg(dev->dev, "Got amthif data\n");
 	dev->iamthif_timer = 0;
 
-	if (cb) {
-		timeout = cb->read_time +
-			mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
-		dev_dbg(dev->dev, "amthif timeout = %lud\n",
-				timeout);
-
-		if  (time_after(jiffies, timeout)) {
-			dev_dbg(dev->dev, "amthif Time out\n");
-			/* 15 sec for the message has expired */
-			list_del(&cb->list);
-			rets = -ETIME;
-			goto free;
-		}
+	timeout = cb->read_time +
+		mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
+	dev_dbg(dev->dev, "amthif timeout = %lud\n",
+			timeout);
+
+	if  (time_after(jiffies, timeout)) {
+		dev_dbg(dev->dev, "amthif Time out\n");
+		/* 15 sec for the message has expired */
+		list_del_init(&cb->list);
+		rets = -ETIME;
+		goto free;
 	}
 	/* if the whole message will fit remove it from the list */
 	if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
-		list_del(&cb->list);
+		list_del_init(&cb->list);
 	else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
 		/* end of the message has been reached */
-		list_del(&cb->list);
+		list_del_init(&cb->list);
 		rets = 0;
 		goto free;
 	}
@@ -225,15 +212,15 @@ int mei_amthif_read(struct mei_device *dev, struct file *file,
 		 * remove message from deletion list
 		 */
 
-	dev_dbg(dev->dev, "amthif cb->response_buffer size - %d\n",
-	    cb->response_buffer.size);
+	dev_dbg(dev->dev, "amthif cb->buf size - %d\n",
+	    cb->buf.size);
 	dev_dbg(dev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
 
 	/* length is being truncated to PAGE_SIZE, however,
 	 * the buf_idx may point beyond */
 	length = min_t(size_t, length, (cb->buf_idx - *offset));
 
-	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
+	if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
 		dev_dbg(dev->dev, "failed to copy data to userland\n");
 		rets = -EFAULT;
 	} else {
@@ -252,126 +239,88 @@ out:
 }
 
 /**
- * mei_amthif_send_cmd - send amthif command to the ME
+ * mei_amthif_read_start - queue message for sending read credential
  *
- * @dev: the device structure
- * @cb: mei call back struct
+ * @cl: host client
+ * @file: file pointer of message recipient
  *
  * Return: 0 on success, <0 on failure.
- *
  */
-static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
+static int mei_amthif_read_start(struct mei_cl *cl, struct file *file)
 {
-	struct mei_msg_hdr mei_hdr;
-	struct mei_cl *cl;
-	int ret;
-
-	if (!dev || !cb)
-		return -ENODEV;
+	struct mei_device *dev = cl->dev;
+	struct mei_cl_cb *cb;
+	size_t length = dev->iamthif_mtu;
+	int rets;
 
-	dev_dbg(dev->dev, "write data to amthif client.\n");
+	cb = mei_io_cb_init(cl, MEI_FOP_READ, file);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto err;
+	}
 
-	dev->iamthif_state = MEI_IAMTHIF_WRITING;
-	dev->iamthif_current_cb = cb;
-	dev->iamthif_file_object = cb->file_object;
-	dev->iamthif_canceled = false;
-	dev->iamthif_ioctl = true;
-	dev->iamthif_msg_buf_size = cb->request_buffer.size;
-	memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
-	       cb->request_buffer.size);
-	cl = &dev->iamthif_cl;
+	rets = mei_io_cb_alloc_buf(cb, length);
+	if (rets)
+		goto err;
 
-	ret = mei_cl_flow_ctrl_creds(cl);
-	if (ret < 0)
-		return ret;
+	list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 
-	if (ret && mei_hbuf_acquire(dev)) {
-		ret = 0;
-		if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
-			mei_hdr.length = mei_hbuf_max_len(dev);
-			mei_hdr.msg_complete = 0;
-		} else {
-			mei_hdr.length = cb->request_buffer.size;
-			mei_hdr.msg_complete = 1;
-		}
+	dev->iamthif_state = MEI_IAMTHIF_READING;
+	dev->iamthif_file_object = cb->file_object;
+	dev->iamthif_current_cb = cb;
 
-		mei_hdr.host_addr = cl->host_client_id;
-		mei_hdr.me_addr = cl->me_client_id;
-		mei_hdr.reserved = 0;
-		mei_hdr.internal = 0;
-		dev->iamthif_msg_buf_index += mei_hdr.length;
-		ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
-		if (ret)
-			return ret;
-
-		if (mei_hdr.msg_complete) {
-			if (mei_cl_flow_ctrl_reduce(cl))
-				return -EIO;
-			dev->iamthif_flow_control_pending = true;
-			dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
-			dev_dbg(dev->dev, "add amthif cb to write waiting list\n");
-			dev->iamthif_current_cb = cb;
-			dev->iamthif_file_object = cb->file_object;
-			list_add_tail(&cb->list, &dev->write_waiting_list.list);
-		} else {
-			dev_dbg(dev->dev, "message does not complete, so add amthif cb to write list.\n");
-			list_add_tail(&cb->list, &dev->write_list.list);
-		}
-	} else {
-		list_add_tail(&cb->list, &dev->write_list.list);
-	}
 	return 0;
+err:
+	mei_io_cb_free(cb);
+	return rets;
 }
 
 /**
- * mei_amthif_write - write amthif data to amthif client
+ * mei_amthif_send_cmd - send amthif command to the ME
  *
- * @dev: the device structure
+ * @cl: the host client
  * @cb: mei call back struct
  *
  * Return: 0 on success, <0 on failure.
- *
  */
-int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
+static int mei_amthif_send_cmd(struct mei_cl *cl, struct mei_cl_cb *cb)
 {
+	struct mei_device *dev;
 	int ret;
 
-	if (!dev || !cb)
+	if (!cl->dev || !cb)
 		return -ENODEV;
 
-	ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
-	if (ret)
+	dev = cl->dev;
+
+	dev->iamthif_state = MEI_IAMTHIF_WRITING;
+	dev->iamthif_current_cb = cb;
+	dev->iamthif_file_object = cb->file_object;
+	dev->iamthif_canceled = false;
+
+	ret = mei_cl_write(cl, cb, false);
+	if (ret < 0)
 		return ret;
 
-	cb->fop_type = MEI_FOP_WRITE;
+	if (cb->completed)
+		cb->status = mei_amthif_read_start(cl, cb->file_object);
 
-	if (!list_empty(&dev->amthif_cmd_list.list) ||
-	    dev->iamthif_state != MEI_IAMTHIF_IDLE) {
-		dev_dbg(dev->dev,
-			"amthif state = %d\n", dev->iamthif_state);
-		dev_dbg(dev->dev, "AMTHIF: add cb to the wait list\n");
-		list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
-		return 0;
-	}
-	return mei_amthif_send_cmd(dev, cb);
+	return 0;
 }
+
 /**
  * mei_amthif_run_next_cmd - send next amt command from queue
  *
  * @dev: the device structure
+ *
+ * Return: 0 on success, <0 on failure.
  */
-void mei_amthif_run_next_cmd(struct mei_device *dev)
+int mei_amthif_run_next_cmd(struct mei_device *dev)
 {
+	struct mei_cl *cl = &dev->iamthif_cl;
 	struct mei_cl_cb *cb;
-	int ret;
-
-	if (!dev)
-		return;
 
-	dev->iamthif_msg_buf_size = 0;
-	dev->iamthif_msg_buf_index = 0;
 	dev->iamthif_canceled = false;
-	dev->iamthif_ioctl = true;
 	dev->iamthif_state = MEI_IAMTHIF_IDLE;
 	dev->iamthif_timer = 0;
 	dev->iamthif_file_object = NULL;
@@ -381,13 +330,48 @@ void mei_amthif_run_next_cmd(struct mei_device *dev)
 	cb = list_first_entry_or_null(&dev->amthif_cmd_list.list,
 					typeof(*cb), list);
 	if (!cb)
-		return;
-	list_del(&cb->list);
-	ret =  mei_amthif_send_cmd(dev, cb);
-	if (ret)
-		dev_warn(dev->dev, "amthif write failed status = %d\n", ret);
+		return 0;
+
+	list_del_init(&cb->list);
+	return mei_amthif_send_cmd(cl, cb);
 }
 
+/**
+ * mei_amthif_write - write amthif data to amthif client
+ *
+ * @cl: host client
+ * @cb: mei call back struct
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+
+	struct mei_device *dev;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	if (WARN_ON(!cb))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
+	return mei_amthif_run_next_cmd(dev);
+}
+
+/**
+ * mei_amthif_poll - the amthif poll function
+ *
+ * @dev: the device structure
+ * @file: pointer to file structure
+ * @wait: pointer to poll_table structure
+ *
+ * Return: poll mask
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
 
 unsigned int mei_amthif_poll(struct mei_device *dev,
 		struct file *file, poll_table *wait)
@@ -396,19 +380,12 @@ unsigned int mei_amthif_poll(struct mei_device *dev,
 
 	poll_wait(file, &dev->iamthif_cl.wait, wait);
 
-	mutex_lock(&dev->device_lock);
-	if (!mei_cl_is_connected(&dev->iamthif_cl)) {
-
-		mask = POLLERR;
-
-	} else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
-		   dev->iamthif_file_object == file) {
+	if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
+	    dev->iamthif_file_object == file) {
 
-		mask |= (POLLIN | POLLRDNORM);
-		dev_dbg(dev->dev, "run next amthif cb\n");
+		mask |= POLLIN | POLLRDNORM;
 		mei_amthif_run_next_cmd(dev);
 	}
-	mutex_unlock(&dev->device_lock);
 
 	return mask;
 }
@@ -427,71 +404,14 @@ unsigned int mei_amthif_poll(struct mei_device *dev,
 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 			 struct mei_cl_cb *cmpl_list)
 {
-	struct mei_device *dev = cl->dev;
-	struct mei_msg_hdr mei_hdr;
-	size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
-	u32 msg_slots = mei_data2slots(len);
-	int slots;
-	int rets;
-
-	rets = mei_cl_flow_ctrl_creds(cl);
-	if (rets < 0)
-		return rets;
-
-	if (rets == 0) {
-		cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
-		return 0;
-	}
-
-	mei_hdr.host_addr = cl->host_client_id;
-	mei_hdr.me_addr = cl->me_client_id;
-	mei_hdr.reserved = 0;
-	mei_hdr.internal = 0;
-
-	slots = mei_hbuf_empty_slots(dev);
-
-	if (slots >= msg_slots) {
-		mei_hdr.length = len;
-		mei_hdr.msg_complete = 1;
-	/* Split the message only if we can write the whole host buffer */
-	} else if (slots == dev->hbuf_depth) {
-		msg_slots = slots;
-		len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
-		mei_hdr.length = len;
-		mei_hdr.msg_complete = 0;
-	} else {
-		/* wait for next time the host buffer is empty */
-		return 0;
-	}
-
-	dev_dbg(dev->dev, MEI_HDR_FMT,  MEI_HDR_PRM(&mei_hdr));
-
-	rets = mei_write_message(dev, &mei_hdr,
-			dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
-	if (rets) {
-		dev->iamthif_state = MEI_IAMTHIF_IDLE;
-		cl->status = rets;
-		list_del(&cb->list);
-		return rets;
-	}
-
-	if (mei_cl_flow_ctrl_reduce(cl))
-		return -EIO;
-
-	dev->iamthif_msg_buf_index += mei_hdr.length;
-	cl->status = 0;
-
-	if (mei_hdr.msg_complete) {
-		dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
-		dev->iamthif_flow_control_pending = true;
-
-		/* save iamthif cb sent to amthif client */
-		cb->buf_idx = dev->iamthif_msg_buf_index;
-		dev->iamthif_current_cb = cb;
+	int ret;
 
-		list_move_tail(&cb->list, &dev->write_waiting_list.list);
-	}
+	ret = mei_cl_irq_write(cl, cb, cmpl_list);
+	if (ret)
+		return ret;
 
+	if (cb->completed)
+		cb->status = mei_amthif_read_start(cl, cb->file_object);
 
 	return 0;
 }
@@ -500,83 +420,35 @@ int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
  * mei_amthif_irq_read_msg - read routine after ISR to
  *			handle the read amthif message
  *
- * @dev: the device structure
+ * @cl: mei client
  * @mei_hdr: header of amthif message
- * @complete_list: An instance of our list structure
+ * @cmpl_list: completed callbacks list
  *
- * Return: 0 on success, <0 on failure.
+ * Return: -ENODEV if cb is NULL 0 otherwise; error message is in cb->status
  */
-int mei_amthif_irq_read_msg(struct mei_device *dev,
+int mei_amthif_irq_read_msg(struct mei_cl *cl,
 			    struct mei_msg_hdr *mei_hdr,
-			    struct mei_cl_cb *complete_list)
+			    struct mei_cl_cb *cmpl_list)
 {
-	struct mei_cl_cb *cb;
-	unsigned char *buffer;
-
-	BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
-	BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
+	struct mei_device *dev;
+	int ret;
 
-	buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
-	BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
+	dev = cl->dev;
 
-	mei_read_slots(dev, buffer, mei_hdr->length);
+	if (dev->iamthif_state != MEI_IAMTHIF_READING)
+		return 0;
 
-	dev->iamthif_msg_buf_index += mei_hdr->length;
+	ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
+	if (ret)
+		return ret;
 
 	if (!mei_hdr->msg_complete)
 		return 0;
 
-	dev_dbg(dev->dev, "amthif_message_buffer_index =%d\n",
-			mei_hdr->length);
-
 	dev_dbg(dev->dev, "completed amthif read.\n ");
-	if (!dev->iamthif_current_cb)
-		return -ENODEV;
-
-	cb = dev->iamthif_current_cb;
 	dev->iamthif_current_cb = NULL;
-
 	dev->iamthif_stall_timer = 0;
-	cb->buf_idx = dev->iamthif_msg_buf_index;
-	cb->read_time = jiffies;
-	if (dev->iamthif_ioctl) {
-		/* found the iamthif cb */
-		dev_dbg(dev->dev, "complete the amthif read cb.\n ");
-		dev_dbg(dev->dev, "add the amthif read cb to complete.\n ");
-		list_add_tail(&cb->list, &complete_list->list);
-	}
-	return 0;
-}
-
-/**
- * mei_amthif_irq_read - prepares to read amthif data.
- *
- * @dev: the device structure.
- * @slots: free slots.
- *
- * Return: 0, OK; otherwise, error.
- */
-int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
-{
-	u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
-
-	if (*slots < msg_slots)
-		return -EMSGSIZE;
-
-	*slots -= msg_slots;
-
-	if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
-		dev_dbg(dev->dev, "iamthif flow control failed\n");
-		return -EIO;
-	}
 
-	dev_dbg(dev->dev, "iamthif flow control success\n");
-	dev->iamthif_state = MEI_IAMTHIF_READING;
-	dev->iamthif_flow_control_pending = false;
-	dev->iamthif_msg_buf_index = 0;
-	dev->iamthif_msg_buf_size = 0;
-	dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
-	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
 	return 0;
 }
 
@@ -588,17 +460,30 @@ int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
  */
 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 {
+
+	if (cb->fop_type == MEI_FOP_WRITE) {
+		if (!cb->status) {
+			dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
+			mei_io_cb_free(cb);
+			return;
+		}
+		/*
+		 * in case of error enqueue the write cb to complete read list
+		 * so it can be propagated to the reader
+		 */
+		list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
+		wake_up_interruptible(&dev->iamthif_cl.wait);
+		return;
+	}
+
 	if (dev->iamthif_canceled != 1) {
 		dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
 		dev->iamthif_stall_timer = 0;
-		memcpy(cb->response_buffer.data,
-				dev->iamthif_msg_buf,
-				dev->iamthif_msg_buf_index);
 		list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
 		dev_dbg(dev->dev, "amthif read completed\n");
 		dev->iamthif_timer = jiffies;
 		dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
-				dev->iamthif_timer);
+			dev->iamthif_timer);
 	} else {
 		mei_amthif_run_next_cmd(dev);
 	}
@@ -623,26 +508,22 @@ void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 static bool mei_clear_list(struct mei_device *dev,
 		const struct file *file, struct list_head *mei_cb_list)
 {
-	struct mei_cl_cb *cb_pos = NULL;
-	struct mei_cl_cb *cb_next = NULL;
+	struct mei_cl *cl = &dev->iamthif_cl;
+	struct mei_cl_cb *cb, *next;
 	bool removed = false;
 
 	/* list all list member */
-	list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
+	list_for_each_entry_safe(cb, next, mei_cb_list, list) {
 		/* check if list member associated with a file */
-		if (file == cb_pos->file_object) {
-			/* remove member from the list */
-			list_del(&cb_pos->list);
+		if (file == cb->file_object) {
 			/* check if cb equal to current iamthif cb */
-			if (dev->iamthif_current_cb == cb_pos) {
+			if (dev->iamthif_current_cb == cb) {
 				dev->iamthif_current_cb = NULL;
 				/* send flow control to iamthif client */
-				mei_hbm_cl_flow_control_req(dev,
-							&dev->iamthif_cl);
+				mei_hbm_cl_flow_control_req(dev, cl);
 			}
 			/* free all allocated buffers */
-			mei_io_cb_free(cb_pos);
-			cb_pos = NULL;
+			mei_io_cb_free(cb);
 			removed = true;
 		}
 	}
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index be767f4db26a..4cf38c39878a 100644
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -238,7 +238,7 @@ static ssize_t ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
 	dev = cl->dev;
 
 	mutex_lock(&dev->device_lock);
-	if (cl->state != MEI_FILE_CONNECTED) {
+	if (!mei_cl_is_connected(cl)) {
 		rets = -ENODEV;
 		goto out;
 	}
@@ -255,17 +255,13 @@ static ssize_t ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
 		goto out;
 	}
 
-	cb = mei_io_cb_init(cl, NULL);
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL);
 	if (!cb) {
 		rets = -ENOMEM;
 		goto out;
 	}
 
-	rets = mei_io_cb_alloc_req_buf(cb, length);
-	if (rets < 0)
-		goto out;
-
-	memcpy(cb->request_buffer.data, buf, length);
+	memcpy(cb->buf.data, buf, length);
 
 	rets = mei_cl_write(cl, cb, blocking);
 
@@ -292,20 +288,21 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 
 	mutex_lock(&dev->device_lock);
 
-	if (!cl->read_cb) {
-		rets = mei_cl_read_start(cl, length);
-		if (rets < 0)
-			goto out;
-	}
+	cb = mei_cl_read_cb(cl, NULL);
+	if (cb)
+		goto copy;
 
-	if (cl->reading_state != MEI_READ_COMPLETE &&
-	    !waitqueue_active(&cl->rx_wait)) {
+	rets = mei_cl_read_start(cl, length, NULL);
+	if (rets && rets != -EBUSY)
+		goto out;
+
+	if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
 
 		mutex_unlock(&dev->device_lock);
 
 		if (wait_event_interruptible(cl->rx_wait,
-				cl->reading_state == MEI_READ_COMPLETE  ||
-				mei_cl_is_transitioning(cl))) {
+				(!list_empty(&cl->rd_completed)) ||
+				(!mei_cl_is_connected(cl)))) {
 
 			if (signal_pending(current))
 				return -EINTR;
@@ -313,23 +310,31 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 		}
 
 		mutex_lock(&dev->device_lock);
-	}
 
-	cb = cl->read_cb;
+		if (!mei_cl_is_connected(cl)) {
+			rets = -EBUSY;
+			goto out;
+		}
+	}
 
-	if (cl->reading_state != MEI_READ_COMPLETE) {
+	cb = mei_cl_read_cb(cl, NULL);
+	if (!cb) {
 		rets = 0;
 		goto out;
 	}
 
+copy:
+	if (cb->status) {
+		rets = cb->status;
+		goto free;
+	}
+
 	r_length = min_t(size_t, length, cb->buf_idx);
-	memcpy(buf, cb->response_buffer.data, r_length);
+	memcpy(buf, cb->buf.data, r_length);
 	rets = r_length;
 
+free:
 	mei_io_cb_free(cb);
-	cl->reading_state = MEI_IDLE;
-	cl->read_cb = NULL;
-
 out:
 	mutex_unlock(&dev->device_lock);
 
@@ -386,7 +391,7 @@ static void mei_bus_event_work(struct work_struct *work)
 	device->events = 0;
 
 	/* Prepare for the next read */
-	mei_cl_read_start(device->cl, 0);
+	mei_cl_read_start(device->cl, 0, NULL);
 }
 
 int mei_cl_register_event_cb(struct mei_cl_device *device,
@@ -400,7 +405,7 @@ int mei_cl_register_event_cb(struct mei_cl_device *device,
 	device->event_context = context;
 	INIT_WORK(&device->event_work, mei_bus_event_work);
 
-	mei_cl_read_start(device->cl, 0);
+	mei_cl_read_start(device->cl, 0, NULL);
 
 	return 0;
 }
@@ -441,8 +446,8 @@ int mei_cl_enable_device(struct mei_cl_device *device)
 
 	mutex_unlock(&dev->device_lock);
 
-	if (device->event_cb && !cl->read_cb)
-		mei_cl_read_start(device->cl, 0);
+	if (device->event_cb)
+		mei_cl_read_start(device->cl, 0, NULL);
 
 	if (!device->ops || !device->ops->enable)
 		return 0;
@@ -462,54 +467,34 @@ int mei_cl_disable_device(struct mei_cl_device *device)
 
 	dev = cl->dev;
 
+	if (device->ops && device->ops->disable)
+		device->ops->disable(device);
+
+	device->event_cb = NULL;
+
 	mutex_lock(&dev->device_lock);
 
-	if (cl->state != MEI_FILE_CONNECTED) {
-		mutex_unlock(&dev->device_lock);
+	if (!mei_cl_is_connected(cl)) {
 		dev_err(dev->dev, "Already disconnected");
-
-		return 0;
+		err = 0;
+		goto out;
 	}
 
 	cl->state = MEI_FILE_DISCONNECTING;
 
 	err = mei_cl_disconnect(cl);
 	if (err < 0) {
-		mutex_unlock(&dev->device_lock);
-		dev_err(dev->dev,
-			"Could not disconnect from the ME client");
-
-		return err;
+		dev_err(dev->dev, "Could not disconnect from the ME client");
+		goto out;
 	}
 
 	/* Flush queues and remove any pending read */
-	mei_cl_flush_queues(cl);
-
-	if (cl->read_cb) {
-		struct mei_cl_cb *cb = NULL;
-
-		cb = mei_cl_find_read_cb(cl);
-		/* Remove entry from read list */
-		if (cb)
-			list_del(&cb->list);
-
-		cb = cl->read_cb;
-		cl->read_cb = NULL;
-
-		if (cb) {
-			mei_io_cb_free(cb);
-			cb = NULL;
-		}
-	}
-
-	device->event_cb = NULL;
+	mei_cl_flush_queues(cl, NULL);
 
+out:
 	mutex_unlock(&dev->device_lock);
+	return err;
 
-	if (!device->ops || !device->ops->disable)
-		return 0;
-
-	return device->ops->disable(device);
 }
 EXPORT_SYMBOL_GPL(mei_cl_disable_device);
 
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index dfbddfe1c7a0..1e99ef6a54a2 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -48,14 +48,14 @@ void mei_me_cl_init(struct mei_me_client *me_cl)
  */
 struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
 {
-	if (me_cl)
-		kref_get(&me_cl->refcnt);
+	if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
+		return me_cl;
 
-	return me_cl;
+	return NULL;
 }
 
 /**
- * mei_me_cl_release - unlink and free me client
+ * mei_me_cl_release - free me client
  *
  * Locking: called under "dev->device_lock" lock
  *
@@ -65,9 +65,10 @@ static void mei_me_cl_release(struct kref *ref)
 {
 	struct mei_me_client *me_cl =
 		container_of(ref, struct mei_me_client, refcnt);
-	list_del(&me_cl->list);
+
 	kfree(me_cl);
 }
+
 /**
  * mei_me_cl_put - decrease me client refcount and free client if necessary
  *
@@ -82,51 +83,146 @@ void mei_me_cl_put(struct mei_me_client *me_cl)
 }
 
 /**
- * mei_me_cl_by_uuid - locate me client by uuid
+ * __mei_me_cl_del  - delete me client form the list and decrease
+ *     reference counter
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+	if (!me_cl)
+		return;
+
+	list_del(&me_cl->list);
+	mei_me_cl_put(me_cl);
+}
+
+/**
+ * mei_me_cl_add - add me client to the list
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ */
+void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+	down_write(&dev->me_clients_rwsem);
+	list_add(&me_cl->list, &dev->me_clients);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * __mei_me_cl_by_uuid - locate me client by uuid
  *	increases ref count
  *
  * @dev: mei device
  * @uuid: me client uuid
  *
- * Locking: called under "dev->device_lock" lock
- *
  * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
  */
-struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev,
+static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
 					const uuid_le *uuid)
 {
 	struct mei_me_client *me_cl;
+	const uuid_le *pn;
 
-	list_for_each_entry(me_cl, &dev->me_clients, list)
-		if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0)
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0)
 			return mei_me_cl_get(me_cl);
+	}
 
 	return NULL;
 }
 
 /**
+ * mei_me_cl_by_uuid - locate me client by uuid
+ *	increases ref count
+ *
+ * @dev: mei device
+ * @uuid: me client uuid
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
  * mei_me_cl_by_id - locate me client by client id
  *	increases ref count
  *
  * @dev: the device structure
  * @client_id: me client id
  *
- * Locking: called under "dev->device_lock" lock
- *
  * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
  */
 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
 {
 
+	struct mei_me_client *__me_cl, *me_cl = NULL;
+
+	down_read(&dev->me_clients_rwsem);
+	list_for_each_entry(__me_cl, &dev->me_clients, list) {
+		if (__me_cl->client_id == client_id) {
+			me_cl = mei_me_cl_get(__me_cl);
+			break;
+		}
+	}
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @client_id: me client id
+ *
+ * Return: me client or null if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id)
+{
 	struct mei_me_client *me_cl;
+	const uuid_le *pn;
+
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 
-	list_for_each_entry(me_cl, &dev->me_clients, list)
-		if (me_cl->client_id == client_id)
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0 &&
+		    me_cl->client_id == client_id)
 			return mei_me_cl_get(me_cl);
+	}
 
 	return NULL;
 }
 
+
 /**
  * mei_me_cl_by_uuid_id - locate me client by client id and uuid
  *	increases ref count
@@ -135,21 +231,18 @@ struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
  * @uuid: me client uuid
  * @client_id: me client id
  *
- * Locking: called under "dev->device_lock" lock
- *
- * Return: me client or NULL if not found
+ * Return: me client or null if not found
  */
 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
 					   const uuid_le *uuid, u8 client_id)
 {
 	struct mei_me_client *me_cl;
 
-	list_for_each_entry(me_cl, &dev->me_clients, list)
-		if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0 &&
-		    me_cl->client_id == client_id)
-			return mei_me_cl_get(me_cl);
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
+	up_read(&dev->me_clients_rwsem);
 
-	return NULL;
+	return me_cl;
 }
 
 /**
@@ -162,12 +255,14 @@ struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
  */
 void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
 {
-	struct mei_me_client *me_cl, *next;
+	struct mei_me_client *me_cl;
 
 	dev_dbg(dev->dev, "remove %pUl\n", uuid);
-	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
-		if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0)
-			mei_me_cl_put(me_cl);
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
 }
 
 /**
@@ -181,15 +276,14 @@ void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
  */
 void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
 {
-	struct mei_me_client *me_cl, *next;
-	const uuid_le *pn;
+	struct mei_me_client *me_cl;
 
 	dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
-	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) {
-		pn =  &me_cl->props.protocol_name;
-		if (me_cl->client_id == id && uuid_le_cmp(*uuid, *pn) == 0)
-			mei_me_cl_put(me_cl);
-	}
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
+	__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
 }
 
 /**
@@ -203,12 +297,12 @@ void mei_me_cl_rm_all(struct mei_device *dev)
 {
 	struct mei_me_client *me_cl, *next;
 
+	down_write(&dev->me_clients_rwsem);
 	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
-			mei_me_cl_put(me_cl);
+		__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
 }
 
-
-
 /**
  * mei_cl_cmp_id - tells if the clients are the same
  *
@@ -227,7 +321,48 @@ static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 }
 
 /**
- * mei_io_list_flush - removes cbs belonging to cl.
+ * mei_io_cb_free - free mei_cb_private related memory
+ *
+ * @cb: mei callback struct
+ */
+void mei_io_cb_free(struct mei_cl_cb *cb)
+{
+	if (cb == NULL)
+		return;
+
+	list_del(&cb->list);
+	kfree(cb->buf.data);
+	kfree(cb);
+}
+
+/**
+ * mei_io_cb_init - allocate and initialize io callback
+ *
+ * @cl: mei client
+ * @type: operation type
+ * @fp: pointer to file structure
+ *
+ * Return: mei_cl_cb pointer or NULL;
+ */
+struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
+				 struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+	if (!cb)
+		return NULL;
+
+	INIT_LIST_HEAD(&cb->list);
+	cb->file_object = fp;
+	cb->cl = cl;
+	cb->buf_idx = 0;
+	cb->fop_type = type;
+	return cb;
+}
+
+/**
+ * __mei_io_list_flush - removes and frees cbs belonging to cl.
  *
  * @list:  an instance of our list structure
  * @cl:    host client, can be NULL for flushing the whole list
@@ -236,13 +371,12 @@ static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 static void __mei_io_list_flush(struct mei_cl_cb *list,
 				struct mei_cl *cl, bool free)
 {
-	struct mei_cl_cb *cb;
-	struct mei_cl_cb *next;
+	struct mei_cl_cb *cb, *next;
 
 	/* enable removing everything if no cl is specified */
 	list_for_each_entry_safe(cb, next, &list->list, list) {
 		if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
-			list_del(&cb->list);
+			list_del_init(&cb->list);
 			if (free)
 				mei_io_cb_free(cb);
 		}
@@ -260,7 +394,6 @@ void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 	__mei_io_list_flush(list, cl, false);
 }
 
-
 /**
  * mei_io_list_free - removes cb belonging to cl and free them
  *
@@ -273,103 +406,107 @@ static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 }
 
 /**
- * mei_io_cb_free - free mei_cb_private related memory
+ * mei_io_cb_alloc_buf - allocate callback buffer
  *
- * @cb: mei callback struct
+ * @cb: io callback structure
+ * @length: size of the buffer
+ *
+ * Return: 0 on success
+ *         -EINVAL if cb is NULL
+ *         -ENOMEM if allocation failed
  */
-void mei_io_cb_free(struct mei_cl_cb *cb)
+int mei_io_cb_alloc_buf(struct mei_cl_cb *cb, size_t length)
 {
-	if (cb == NULL)
-		return;
+	if (!cb)
+		return -EINVAL;
 
-	kfree(cb->request_buffer.data);
-	kfree(cb->response_buffer.data);
-	kfree(cb);
+	if (length == 0)
+		return 0;
+
+	cb->buf.data = kmalloc(length, GFP_KERNEL);
+	if (!cb->buf.data)
+		return -ENOMEM;
+	cb->buf.size = length;
+	return 0;
 }
 
 /**
- * mei_io_cb_init - allocate and initialize io callback
+ * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
  *
- * @cl: mei client
- * @fp: pointer to file structure
+ * @cl: host client
+ * @length: size of the buffer
+ * @type: operation type
+ * @fp: associated file pointer (might be NULL)
  *
- * Return: mei_cl_cb pointer or NULL;
+ * Return: cb on success and NULL on failure
  */
-struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp)
+struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
+				  enum mei_cb_file_ops type, struct file *fp)
 {
 	struct mei_cl_cb *cb;
 
-	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+	cb = mei_io_cb_init(cl, type, fp);
 	if (!cb)
 		return NULL;
 
-	mei_io_list_init(cb);
+	if (mei_io_cb_alloc_buf(cb, length)) {
+		mei_io_cb_free(cb);
+		return NULL;
+	}
 
-	cb->file_object = fp;
-	cb->cl = cl;
-	cb->buf_idx = 0;
 	return cb;
 }
 
 /**
- * mei_io_cb_alloc_req_buf - allocate request buffer
+ * mei_cl_read_cb - find this cl's callback in the read list
+ *     for a specific file
  *
- * @cb: io callback structure
- * @length: size of the buffer
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
  *
- * Return: 0 on success
- *         -EINVAL if cb is NULL
- *         -ENOMEM if allocation failed
+ * Return: cb on success, NULL if cb is not found
  */
-int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length)
+struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 {
-	if (!cb)
-		return -EINVAL;
+	struct mei_cl_cb *cb;
 
-	if (length == 0)
-		return 0;
+	list_for_each_entry(cb, &cl->rd_completed, list)
+		if (!fp || fp == cb->file_object)
+			return cb;
 
-	cb->request_buffer.data = kmalloc(length, GFP_KERNEL);
-	if (!cb->request_buffer.data)
-		return -ENOMEM;
-	cb->request_buffer.size = length;
-	return 0;
+	return NULL;
 }
+
 /**
- * mei_io_cb_alloc_resp_buf - allocate response buffer
- *
- * @cb: io callback structure
- * @length: size of the buffer
+ * mei_cl_read_cb_flush - free client's read pending and completed cbs
+ *   for a specific file
  *
- * Return: 0 on success
- *         -EINVAL if cb is NULL
- *         -ENOMEM if allocation failed
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
  */
-int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length)
+void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
 {
-	if (!cb)
-		return -EINVAL;
+	struct mei_cl_cb *cb, *next;
 
-	if (length == 0)
-		return 0;
-
-	cb->response_buffer.data = kmalloc(length, GFP_KERNEL);
-	if (!cb->response_buffer.data)
-		return -ENOMEM;
-	cb->response_buffer.size = length;
-	return 0;
-}
+	list_for_each_entry_safe(cb, next, &cl->rd_completed, list)
+		if (!fp || fp == cb->file_object)
+			mei_io_cb_free(cb);
 
 
+	list_for_each_entry_safe(cb, next, &cl->rd_pending, list)
+		if (!fp || fp == cb->file_object)
+			mei_io_cb_free(cb);
+}
 
 /**
  * mei_cl_flush_queues - flushes queue lists belonging to cl.
  *
  * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
  *
  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
  */
-int mei_cl_flush_queues(struct mei_cl *cl)
+int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 {
 	struct mei_device *dev;
 
@@ -379,13 +516,15 @@ int mei_cl_flush_queues(struct mei_cl *cl)
 	dev = cl->dev;
 
 	cl_dbg(dev, cl, "remove list entry belonging to cl\n");
-	mei_io_list_flush(&cl->dev->read_list, cl);
 	mei_io_list_free(&cl->dev->write_list, cl);
 	mei_io_list_free(&cl->dev->write_waiting_list, cl);
 	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 	mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 	mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
+
+	mei_cl_read_cb_flush(cl, fp);
+
 	return 0;
 }
 
@@ -402,9 +541,10 @@ void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 	init_waitqueue_head(&cl->wait);
 	init_waitqueue_head(&cl->rx_wait);
 	init_waitqueue_head(&cl->tx_wait);
+	INIT_LIST_HEAD(&cl->rd_completed);
+	INIT_LIST_HEAD(&cl->rd_pending);
 	INIT_LIST_HEAD(&cl->link);
 	INIT_LIST_HEAD(&cl->device_link);
-	cl->reading_state = MEI_IDLE;
 	cl->writing_state = MEI_IDLE;
 	cl->dev = dev;
 }
@@ -429,31 +569,14 @@ struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 }
 
 /**
- * mei_cl_find_read_cb - find this cl's callback in the read list
+ * mei_cl_link - allocate host id in the host map
  *
  * @cl: host client
- *
- * Return: cb on success, NULL on error
- */
-struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
-{
-	struct mei_device *dev = cl->dev;
-	struct mei_cl_cb *cb;
-
-	list_for_each_entry(cb, &dev->read_list.list, list)
-		if (mei_cl_cmp_id(cl, cb->cl))
-			return cb;
-	return NULL;
-}
-
-/** mei_cl_link: allocate host id in the host map
- *
- * @cl - host client
- * @id - fixed host id or -1 for generic one
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
  *
  * Return: 0 on success
  *	-EINVAL on incorrect values
- *	-ENONET if client not found
+ *	-EMFILE if open count exceeded.
  */
 int mei_cl_link(struct mei_cl *cl, int id)
 {
@@ -535,28 +658,31 @@ int mei_cl_unlink(struct mei_cl *cl)
 
 void mei_host_client_init(struct work_struct *work)
 {
-	struct mei_device *dev = container_of(work,
-					      struct mei_device, init_work);
+	struct mei_device *dev =
+		container_of(work, struct mei_device, init_work);
 	struct mei_me_client *me_cl;
-	struct mei_client_properties *props;
 
 	mutex_lock(&dev->device_lock);
 
-	list_for_each_entry(me_cl, &dev->me_clients, list) {
-		props = &me_cl->props;
 
-		if (!uuid_le_cmp(props->protocol_name, mei_amthif_guid))
-			mei_amthif_host_init(dev);
-		else if (!uuid_le_cmp(props->protocol_name, mei_wd_guid))
-			mei_wd_host_init(dev);
-		else if (!uuid_le_cmp(props->protocol_name, mei_nfc_guid))
-			mei_nfc_host_init(dev);
+	me_cl = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
+	if (me_cl)
+		mei_amthif_host_init(dev);
+	mei_me_cl_put(me_cl);
+
+	me_cl = mei_me_cl_by_uuid(dev, &mei_wd_guid);
+	if (me_cl)
+		mei_wd_host_init(dev);
+	mei_me_cl_put(me_cl);
+
+	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
+	if (me_cl)
+		mei_nfc_host_init(dev);
+	mei_me_cl_put(me_cl);
 
-	}
 
 	dev->dev_state = MEI_DEV_ENABLED;
 	dev->reset_count = 0;
-
 	mutex_unlock(&dev->device_lock);
 
 	pm_runtime_mark_last_busy(dev->dev);
@@ -620,13 +746,10 @@ int mei_cl_disconnect(struct mei_cl *cl)
 		return rets;
 	}
 
-	cb = mei_io_cb_init(cl, NULL);
-	if (!cb) {
-		rets = -ENOMEM;
+	cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT, NULL);
+	rets = cb ? 0 : -ENOMEM;
+	if (rets)
 		goto free;
-	}
-
-	cb->fop_type = MEI_FOP_DISCONNECT;
 
 	if (mei_hbuf_acquire(dev)) {
 		if (mei_hbm_cl_disconnect_req(dev, cl)) {
@@ -727,13 +850,10 @@ int mei_cl_connect(struct mei_cl *cl, struct file *file)
 		return rets;
 	}
 
-	cb = mei_io_cb_init(cl, file);
-	if (!cb) {
-		rets = -ENOMEM;
+	cb = mei_io_cb_init(cl, MEI_FOP_CONNECT, file);
+	rets = cb ? 0 : -ENOMEM;
+	if (rets)
 		goto out;
-	}
-
-	cb->fop_type = MEI_FOP_CONNECT;
 
 	/* run hbuf acquire last so we don't have to undo */
 	if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
@@ -756,7 +876,7 @@ int mei_cl_connect(struct mei_cl *cl, struct file *file)
 			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 	mutex_lock(&dev->device_lock);
 
-	if (cl->state != MEI_FILE_CONNECTED) {
+	if (!mei_cl_is_connected(cl)) {
 		cl->state = MEI_FILE_DISCONNECTED;
 		/* something went really wrong */
 		if (!cl->status)
@@ -778,6 +898,37 @@ out:
 }
 
 /**
+ * mei_cl_alloc_linked - allocate and link host client
+ *
+ * @dev: the device structure
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
+ *
+ * Return: cl on success ERR_PTR on failure
+ */
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id)
+{
+	struct mei_cl *cl;
+	int ret;
+
+	cl = mei_cl_allocate(dev);
+	if (!cl) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ret = mei_cl_link(cl, id);
+	if (ret)
+		goto err;
+
+	return cl;
+err:
+	kfree(cl);
+	return ERR_PTR(ret);
+}
+
+
+
+/**
  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
  *
  * @cl: private data of the file object
@@ -866,10 +1017,11 @@ out:
  *
  * @cl: host client
  * @length: number of bytes to read
+ * @fp: pointer to file structure
  *
  * Return: 0 on success, <0 on failure.
  */
-int mei_cl_read_start(struct mei_cl *cl, size_t length)
+int mei_cl_read_start(struct mei_cl *cl, size_t length, struct file *fp)
 {
 	struct mei_device *dev;
 	struct mei_cl_cb *cb;
@@ -884,10 +1036,10 @@ int mei_cl_read_start(struct mei_cl *cl, size_t length)
 	if (!mei_cl_is_connected(cl))
 		return -ENODEV;
 
-	if (cl->read_cb) {
-		cl_dbg(dev, cl, "read is pending.\n");
+	/* HW currently supports only one pending read */
+	if (!list_empty(&cl->rd_pending))
 		return -EBUSY;
-	}
+
 	me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id);
 	if (!me_cl) {
 		cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
@@ -904,29 +1056,21 @@ int mei_cl_read_start(struct mei_cl *cl, size_t length)
 		return rets;
 	}
 
-	cb = mei_io_cb_init(cl, NULL);
-	if (!cb) {
-		rets = -ENOMEM;
-		goto out;
-	}
-
-	rets = mei_io_cb_alloc_resp_buf(cb, length);
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_READ, fp);
+	rets = cb ? 0 : -ENOMEM;
 	if (rets)
 		goto out;
 
-	cb->fop_type = MEI_FOP_READ;
 	if (mei_hbuf_acquire(dev)) {
 		rets = mei_hbm_cl_flow_control_req(dev, cl);
 		if (rets < 0)
 			goto out;
 
-		list_add_tail(&cb->list, &dev->read_list.list);
+		list_add_tail(&cb->list, &cl->rd_pending);
 	} else {
 		list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 	}
 
-	cl->read_cb = cb;
-
 out:
 	cl_dbg(dev, cl, "rpm: autosuspend\n");
 	pm_runtime_mark_last_busy(dev->dev);
@@ -964,7 +1108,7 @@ int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	dev = cl->dev;
 
-	buf = &cb->request_buffer;
+	buf = &cb->buf;
 
 	rets = mei_cl_flow_ctrl_creds(cl);
 	if (rets < 0)
@@ -999,7 +1143,7 @@ int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 	}
 
 	cl_dbg(dev, cl, "buf: size = %d idx = %lu\n",
-			cb->request_buffer.size, cb->buf_idx);
+			cb->buf.size, cb->buf_idx);
 
 	rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
 	if (rets) {
@@ -1011,6 +1155,7 @@ int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 	cl->status = 0;
 	cl->writing_state = MEI_WRITING;
 	cb->buf_idx += mei_hdr.length;
+	cb->completed = mei_hdr.msg_complete == 1;
 
 	if (mei_hdr.msg_complete) {
 		if (mei_cl_flow_ctrl_reduce(cl))
@@ -1048,7 +1193,7 @@ int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
 	dev = cl->dev;
 
 
-	buf = &cb->request_buffer;
+	buf = &cb->buf;
 
 	cl_dbg(dev, cl, "size=%d\n", buf->size);
 
@@ -1059,7 +1204,6 @@ int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
 		return rets;
 	}
 
-	cb->fop_type = MEI_FOP_WRITE;
 	cb->buf_idx = 0;
 	cl->writing_state = MEI_IDLE;
 
@@ -1099,6 +1243,7 @@ int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
 
 	cl->writing_state = MEI_WRITING;
 	cb->buf_idx = mei_hdr.length;
+	cb->completed = mei_hdr.msg_complete == 1;
 
 out:
 	if (mei_hdr.msg_complete) {
@@ -1151,11 +1296,10 @@ void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
 		if (waitqueue_active(&cl->tx_wait))
 			wake_up_interruptible(&cl->tx_wait);
 
-	} else if (cb->fop_type == MEI_FOP_READ &&
-			MEI_READING == cl->reading_state) {
-		cl->reading_state = MEI_READ_COMPLETE;
+	} else if (cb->fop_type == MEI_FOP_READ) {
+		list_add_tail(&cb->list, &cl->rd_completed);
 		if (waitqueue_active(&cl->rx_wait))
-			wake_up_interruptible(&cl->rx_wait);
+			wake_up_interruptible_all(&cl->rx_wait);
 		else
 			mei_cl_bus_rx_event(cl);
 
diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h
index cfcde8e97fc4..0a39e5d45171 100644
--- a/drivers/misc/mei/client.h
+++ b/drivers/misc/mei/client.h
@@ -31,7 +31,10 @@ void mei_me_cl_init(struct mei_me_client *me_cl);
 void mei_me_cl_put(struct mei_me_client *me_cl);
 struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl);
 
-struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev,
+void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl);
+void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl);
+
+struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
 					const uuid_le *uuid);
 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id);
 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
@@ -44,10 +47,10 @@ void mei_me_cl_rm_all(struct mei_device *dev);
 /*
  * MEI IO Functions
  */
-struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp);
+struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
+				 struct file *fp);
 void mei_io_cb_free(struct mei_cl_cb *priv_cb);
-int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length);
-int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length);
+int mei_io_cb_alloc_buf(struct mei_cl_cb *cb, size_t length);
 
 
 /**
@@ -72,9 +75,14 @@ void mei_cl_init(struct mei_cl *cl, struct mei_device *dev);
 int mei_cl_link(struct mei_cl *cl, int id);
 int mei_cl_unlink(struct mei_cl *cl);
 
-int mei_cl_flush_queues(struct mei_cl *cl);
-struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl);
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id);
 
+struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl,
+				 const struct file *fp);
+void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp);
+struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
+				  enum mei_cb_file_ops type, struct file *fp);
+int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp);
 
 int mei_cl_flow_ctrl_creds(struct mei_cl *cl);
 
@@ -82,23 +90,25 @@ int mei_cl_flow_ctrl_reduce(struct mei_cl *cl);
 /*
  *  MEI input output function prototype
  */
+
+/**
+ * mei_cl_is_connected - host client is connected
+ *
+ * @cl: host clinet
+ *
+ * Return: true if the host clinet is connected
+ */
 static inline bool mei_cl_is_connected(struct mei_cl *cl)
 {
-	return  cl->dev &&
-		cl->dev->dev_state == MEI_DEV_ENABLED &&
-		cl->state == MEI_FILE_CONNECTED;
-}
-static inline bool mei_cl_is_transitioning(struct mei_cl *cl)
-{
-	return  MEI_FILE_INITIALIZING == cl->state ||
-		MEI_FILE_DISCONNECTED == cl->state ||
-		MEI_FILE_DISCONNECTING == cl->state;
+	return  cl->state == MEI_FILE_CONNECTED;
 }
 
 bool mei_cl_is_other_connecting(struct mei_cl *cl);
 int mei_cl_disconnect(struct mei_cl *cl);
 int mei_cl_connect(struct mei_cl *cl, struct file *file);
-int mei_cl_read_start(struct mei_cl *cl, size_t length);
+int mei_cl_read_start(struct mei_cl *cl, size_t length, struct file *fp);
+int mei_cl_irq_read_msg(struct mei_cl *cl, struct mei_msg_hdr *hdr,
+			struct mei_cl_cb *cmpl_list);
 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking);
 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 		     struct mei_cl_cb *cmpl_list);
diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
index b125380ee871..d9cd7e6ee484 100644
--- a/drivers/misc/mei/debugfs.c
+++ b/drivers/misc/mei/debugfs.c
@@ -28,7 +28,7 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf,
 					size_t cnt, loff_t *ppos)
 {
 	struct mei_device *dev = fp->private_data;
-	struct mei_me_client *me_cl, *n;
+	struct mei_me_client *me_cl;
 	size_t bufsz = 1;
 	char *buf;
 	int i = 0;
@@ -38,15 +38,14 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf,
 #define HDR \
 "  |id|fix|         UUID                       |con|msg len|sb|refc|\n"
 
-	mutex_lock(&dev->device_lock);
-
+	down_read(&dev->me_clients_rwsem);
 	list_for_each_entry(me_cl, &dev->me_clients, list)
 		bufsz++;
 
 	bufsz *= sizeof(HDR) + 1;
 	buf = kzalloc(bufsz, GFP_KERNEL);
 	if (!buf) {
-		mutex_unlock(&dev->device_lock);
+		up_read(&dev->me_clients_rwsem);
 		return -ENOMEM;
 	}
 
@@ -56,10 +55,9 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf,
 	if (dev->dev_state != MEI_DEV_ENABLED)
 		goto out;
 
-	list_for_each_entry_safe(me_cl, n, &dev->me_clients, list) {
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
 
-		me_cl = mei_me_cl_get(me_cl);
-		if (me_cl) {
+		if (mei_me_cl_get(me_cl)) {
 			pos += scnprintf(buf + pos, bufsz - pos,
 				"%2d|%2d|%3d|%pUl|%3d|%7d|%2d|%4d|\n",
 				i++, me_cl->client_id,
@@ -69,12 +67,13 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf,
 				me_cl->props.max_msg_length,
 				me_cl->props.single_recv_buf,
 				atomic_read(&me_cl->refcnt.refcount));
-		}
 
-		mei_me_cl_put(me_cl);
+			mei_me_cl_put(me_cl);
+		}
 	}
+
 out:
-	mutex_unlock(&dev->device_lock);
+	up_read(&dev->me_clients_rwsem);
 	ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, pos);
 	kfree(buf);
 	return ret;
@@ -118,7 +117,7 @@ static ssize_t mei_dbgfs_read_active(struct file *fp, char __user *ubuf,
 		pos += scnprintf(buf + pos, bufsz - pos,
 			"%2d|%2d|%4d|%5d|%2d|%2d|\n",
 			i, cl->me_client_id, cl->host_client_id, cl->state,
-			cl->reading_state, cl->writing_state);
+			!list_empty(&cl->rd_completed), cl->writing_state);
 		i++;
 	}
 out:
diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index c8412d41e4f1..58da92565c5e 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -338,7 +338,8 @@ static int mei_hbm_me_cl_add(struct mei_device *dev,
 	me_cl->client_id = res->me_addr;
 	me_cl->mei_flow_ctrl_creds = 0;
 
-	list_add(&me_cl->list, &dev->me_clients);
+	mei_me_cl_add(dev, me_cl);
+
 	return 0;
 }
 
@@ -638,7 +639,7 @@ static void mei_hbm_cl_res(struct mei_device *dev,
 			continue;
 
 		if (mei_hbm_cl_addr_equal(cl, rs)) {
-			list_del(&cb->list);
+			list_del_init(&cb->list);
 			break;
 		}
 	}
@@ -683,10 +684,9 @@ static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
 		cl->state = MEI_FILE_DISCONNECTED;
 		cl->timer_count = 0;
 
-		cb = mei_io_cb_init(cl, NULL);
+		cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT_RSP, NULL);
 		if (!cb)
 			return -ENOMEM;
-		cb->fop_type = MEI_FOP_DISCONNECT_RSP;
 		cl_dbg(dev, cl, "add disconnect response as first\n");
 		list_add(&cb->list, &dev->ctrl_wr_list.list);
 	}
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index f8fd503dfbd6..6fb75e62a764 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -25,6 +25,8 @@
 #include "hw-me.h"
 #include "hw-me-regs.h"
 
+#include "mei-trace.h"
+
 /**
  * mei_me_reg_read - Reads 32bit data from the mei device
  *
@@ -61,45 +63,79 @@ static inline void mei_me_reg_write(const struct mei_me_hw *hw,
  *
  * Return: ME_CB_RW register value (u32)
  */
-static u32 mei_me_mecbrw_read(const struct mei_device *dev)
+static inline u32 mei_me_mecbrw_read(const struct mei_device *dev)
 {
 	return mei_me_reg_read(to_me_hw(dev), ME_CB_RW);
 }
+
+/**
+ * mei_me_hcbww_write - write 32bit data to the host circular buffer
+ *
+ * @dev: the device structure
+ * @data: 32bit data to be written to the host circular buffer
+ */
+static inline void mei_me_hcbww_write(struct mei_device *dev, u32 data)
+{
+	mei_me_reg_write(to_me_hw(dev), H_CB_WW, data);
+}
+
 /**
  * mei_me_mecsr_read - Reads 32bit data from the ME CSR
  *
- * @hw: the me hardware structure
+ * @dev: the device structure
  *
  * Return: ME_CSR_HA register value (u32)
  */
-static inline u32 mei_me_mecsr_read(const struct mei_me_hw *hw)
+static inline u32 mei_me_mecsr_read(const struct mei_device *dev)
 {
-	return mei_me_reg_read(hw, ME_CSR_HA);
+	u32 reg;
+
+	reg = mei_me_reg_read(to_me_hw(dev), ME_CSR_HA);
+	trace_mei_reg_read(dev->dev, "ME_CSR_HA", ME_CSR_HA, reg);
+
+	return reg;
 }
 
 /**
  * mei_hcsr_read - Reads 32bit data from the host CSR
  *
- * @hw: the me hardware structure
+ * @dev: the device structure
  *
  * Return: H_CSR register value (u32)
  */
-static inline u32 mei_hcsr_read(const struct mei_me_hw *hw)
+static inline u32 mei_hcsr_read(const struct mei_device *dev)
+{
+	u32 reg;
+
+	reg = mei_me_reg_read(to_me_hw(dev), H_CSR);
+	trace_mei_reg_read(dev->dev, "H_CSR", H_CSR, reg);
+
+	return reg;
+}
+
+/**
+ * mei_hcsr_write - writes H_CSR register to the mei device
+ *
+ * @dev: the device structure
+ * @reg: new register value
+ */
+static inline void mei_hcsr_write(struct mei_device *dev, u32 reg)
 {
-	return mei_me_reg_read(hw, H_CSR);
+	trace_mei_reg_write(dev->dev, "H_CSR", H_CSR, reg);
+	mei_me_reg_write(to_me_hw(dev), H_CSR, reg);
 }
 
 /**
  * mei_hcsr_set - writes H_CSR register to the mei device,
  * and ignores the H_IS bit for it is write-one-to-zero.
  *
- * @hw: the me hardware structure
- * @hcsr: new register value
+ * @dev: the device structure
+ * @reg: new register value
  */
-static inline void mei_hcsr_set(struct mei_me_hw *hw, u32 hcsr)
+static inline void mei_hcsr_set(struct mei_device *dev, u32 reg)
 {
-	hcsr &= ~H_IS;
-	mei_me_reg_write(hw, H_CSR, hcsr);
+	reg &= ~H_IS;
+	mei_hcsr_write(dev, reg);
 }
 
 /**
@@ -141,7 +177,7 @@ static int mei_me_fw_status(struct mei_device *dev,
 static void mei_me_hw_config(struct mei_device *dev)
 {
 	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(to_me_hw(dev));
+	u32 hcsr = mei_hcsr_read(dev);
 	/* Doesn't change in runtime */
 	dev->hbuf_depth = (hcsr & H_CBD) >> 24;
 
@@ -170,11 +206,10 @@ static inline enum mei_pg_state mei_me_pg_state(struct mei_device *dev)
  */
 static void mei_me_intr_clear(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	if ((hcsr & H_IS) == H_IS)
-		mei_me_reg_write(hw, H_CSR, hcsr);
+		mei_hcsr_write(dev, hcsr);
 }
 /**
  * mei_me_intr_enable - enables mei device interrupts
@@ -183,11 +218,10 @@ static void mei_me_intr_clear(struct mei_device *dev)
  */
 static void mei_me_intr_enable(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	hcsr |= H_IE;
-	mei_hcsr_set(hw, hcsr);
+	mei_hcsr_set(dev, hcsr);
 }
 
 /**
@@ -197,11 +231,10 @@ static void mei_me_intr_enable(struct mei_device *dev)
  */
 static void mei_me_intr_disable(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	hcsr  &= ~H_IE;
-	mei_hcsr_set(hw, hcsr);
+	mei_hcsr_set(dev, hcsr);
 }
 
 /**
@@ -211,12 +244,11 @@ static void mei_me_intr_disable(struct mei_device *dev)
  */
 static void mei_me_hw_reset_release(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	hcsr |= H_IG;
 	hcsr &= ~H_RST;
-	mei_hcsr_set(hw, hcsr);
+	mei_hcsr_set(dev, hcsr);
 
 	/* complete this write before we set host ready on another CPU */
 	mmiowb();
@@ -231,8 +263,7 @@ static void mei_me_hw_reset_release(struct mei_device *dev)
  */
 static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	/* H_RST may be found lit before reset is started,
 	 * for example if preceding reset flow hasn't completed.
@@ -242,8 +273,8 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 	if ((hcsr & H_RST) == H_RST) {
 		dev_warn(dev->dev, "H_RST is set = 0x%08X", hcsr);
 		hcsr &= ~H_RST;
-		mei_hcsr_set(hw, hcsr);
-		hcsr = mei_hcsr_read(hw);
+		mei_hcsr_set(dev, hcsr);
+		hcsr = mei_hcsr_read(dev);
 	}
 
 	hcsr |= H_RST | H_IG | H_IS;
@@ -254,13 +285,13 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 		hcsr &= ~H_IE;
 
 	dev->recvd_hw_ready = false;
-	mei_me_reg_write(hw, H_CSR, hcsr);
+	mei_hcsr_write(dev, hcsr);
 
 	/*
 	 * Host reads the H_CSR once to ensure that the
 	 * posted write to H_CSR completes.
 	 */
-	hcsr = mei_hcsr_read(hw);
+	hcsr = mei_hcsr_read(dev);
 
 	if ((hcsr & H_RST) == 0)
 		dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr);
@@ -281,11 +312,10 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
  */
 static void mei_me_host_set_ready(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	hcsr |= H_IE | H_IG | H_RDY;
-	mei_hcsr_set(hw, hcsr);
+	mei_hcsr_set(dev, hcsr);
 }
 
 /**
@@ -296,8 +326,7 @@ static void mei_me_host_set_ready(struct mei_device *dev)
  */
 static bool mei_me_host_is_ready(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
 	return (hcsr & H_RDY) == H_RDY;
 }
@@ -310,8 +339,7 @@ static bool mei_me_host_is_ready(struct mei_device *dev)
  */
 static bool mei_me_hw_is_ready(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 mecsr = mei_me_mecsr_read(hw);
+	u32 mecsr = mei_me_mecsr_read(dev);
 
 	return (mecsr & ME_RDY_HRA) == ME_RDY_HRA;
 }
@@ -368,11 +396,10 @@ static int mei_me_hw_start(struct mei_device *dev)
  */
 static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
 	u32 hcsr;
 	char read_ptr, write_ptr;
 
-	hcsr = mei_hcsr_read(hw);
+	hcsr = mei_hcsr_read(dev);
 
 	read_ptr = (char) ((hcsr & H_CBRP) >> 8);
 	write_ptr = (char) ((hcsr & H_CBWP) >> 16);
@@ -439,7 +466,6 @@ static int mei_me_write_message(struct mei_device *dev,
 			struct mei_msg_hdr *header,
 			unsigned char *buf)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
 	unsigned long rem;
 	unsigned long length = header->length;
 	u32 *reg_buf = (u32 *)buf;
@@ -457,21 +483,21 @@ static int mei_me_write_message(struct mei_device *dev,
 	if (empty_slots < 0 || dw_cnt > empty_slots)
 		return -EMSGSIZE;
 
-	mei_me_reg_write(hw, H_CB_WW, *((u32 *) header));
+	mei_me_hcbww_write(dev, *((u32 *) header));
 
 	for (i = 0; i < length / 4; i++)
-		mei_me_reg_write(hw, H_CB_WW, reg_buf[i]);
+		mei_me_hcbww_write(dev, reg_buf[i]);
 
 	rem = length & 0x3;
 	if (rem > 0) {
 		u32 reg = 0;
 
 		memcpy(&reg, &buf[length - rem], rem);
-		mei_me_reg_write(hw, H_CB_WW, reg);
+		mei_me_hcbww_write(dev, reg);
 	}
 
-	hcsr = mei_hcsr_read(hw) | H_IG;
-	mei_hcsr_set(hw, hcsr);
+	hcsr = mei_hcsr_read(dev) | H_IG;
+	mei_hcsr_set(dev, hcsr);
 	if (!mei_me_hw_is_ready(dev))
 		return -EIO;
 
@@ -487,12 +513,11 @@ static int mei_me_write_message(struct mei_device *dev,
  */
 static int mei_me_count_full_read_slots(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
 	u32 me_csr;
 	char read_ptr, write_ptr;
 	unsigned char buffer_depth, filled_slots;
 
-	me_csr = mei_me_mecsr_read(hw);
+	me_csr = mei_me_mecsr_read(dev);
 	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
 	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
 	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
@@ -518,7 +543,6 @@ static int mei_me_count_full_read_slots(struct mei_device *dev)
 static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
 		    unsigned long buffer_length)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
 	u32 *reg_buf = (u32 *)buffer;
 	u32 hcsr;
 
@@ -531,49 +555,59 @@ static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
 		memcpy(reg_buf, &reg, buffer_length);
 	}
 
-	hcsr = mei_hcsr_read(hw) | H_IG;
-	mei_hcsr_set(hw, hcsr);
+	hcsr = mei_hcsr_read(dev) | H_IG;
+	mei_hcsr_set(dev, hcsr);
 	return 0;
 }
 
 /**
- * mei_me_pg_enter - write pg enter register
+ * mei_me_pg_set - write pg enter register
  *
  * @dev: the device structure
  */
-static void mei_me_pg_enter(struct mei_device *dev)
+static void mei_me_pg_set(struct mei_device *dev)
 {
 	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 reg = mei_me_reg_read(hw, H_HPG_CSR);
+	u32 reg;
+
+	reg = mei_me_reg_read(hw, H_HPG_CSR);
+	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
 
 	reg |= H_HPG_CSR_PGI;
+
+	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
 	mei_me_reg_write(hw, H_HPG_CSR, reg);
 }
 
 /**
- * mei_me_pg_exit - write pg exit register
+ * mei_me_pg_unset - write pg exit register
  *
  * @dev: the device structure
  */
-static void mei_me_pg_exit(struct mei_device *dev)
+static void mei_me_pg_unset(struct mei_device *dev)
 {
 	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 reg = mei_me_reg_read(hw, H_HPG_CSR);
+	u32 reg;
+
+	reg = mei_me_reg_read(hw, H_HPG_CSR);
+	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
 
 	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
 
 	reg |= H_HPG_CSR_PGIHEXR;
+
+	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
 	mei_me_reg_write(hw, H_HPG_CSR, reg);
 }
 
 /**
- * mei_me_pg_set_sync - perform pg entry procedure
+ * mei_me_pg_enter_sync - perform pg entry procedure
  *
  * @dev: the device structure
  *
  * Return: 0 on success an error code otherwise
  */
-int mei_me_pg_set_sync(struct mei_device *dev)
+int mei_me_pg_enter_sync(struct mei_device *dev)
 {
 	struct mei_me_hw *hw = to_me_hw(dev);
 	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
@@ -591,7 +625,7 @@ int mei_me_pg_set_sync(struct mei_device *dev)
 	mutex_lock(&dev->device_lock);
 
 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
-		mei_me_pg_enter(dev);
+		mei_me_pg_set(dev);
 		ret = 0;
 	} else {
 		ret = -ETIME;
@@ -604,13 +638,13 @@ int mei_me_pg_set_sync(struct mei_device *dev)
 }
 
 /**
- * mei_me_pg_unset_sync - perform pg exit procedure
+ * mei_me_pg_exit_sync - perform pg exit procedure
  *
  * @dev: the device structure
  *
  * Return: 0 on success an error code otherwise
  */
-int mei_me_pg_unset_sync(struct mei_device *dev)
+int mei_me_pg_exit_sync(struct mei_device *dev)
 {
 	struct mei_me_hw *hw = to_me_hw(dev);
 	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
@@ -621,7 +655,7 @@ int mei_me_pg_unset_sync(struct mei_device *dev)
 
 	dev->pg_event = MEI_PG_EVENT_WAIT;
 
-	mei_me_pg_exit(dev);
+	mei_me_pg_unset(dev);
 
 	mutex_unlock(&dev->device_lock);
 	wait_event_timeout(dev->wait_pg,
@@ -649,8 +683,7 @@ reply:
  */
 static bool mei_me_pg_is_enabled(struct mei_device *dev)
 {
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 reg = mei_me_reg_read(hw, ME_CSR_HA);
+	u32 reg = mei_me_mecsr_read(dev);
 
 	if ((reg & ME_PGIC_HRA) == 0)
 		goto notsupported;
@@ -683,14 +716,13 @@ notsupported:
 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
 {
 	struct mei_device *dev = (struct mei_device *) dev_id;
-	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 csr_reg = mei_hcsr_read(hw);
+	u32 hcsr = mei_hcsr_read(dev);
 
-	if ((csr_reg & H_IS) != H_IS)
+	if ((hcsr & H_IS) != H_IS)
 		return IRQ_NONE;
 
 	/* clear H_IS bit in H_CSR */
-	mei_me_reg_write(hw, H_CSR, csr_reg);
+	mei_hcsr_write(dev, hcsr);
 
 	return IRQ_WAKE_THREAD;
 }
diff --git a/drivers/misc/mei/hw-me.h b/drivers/misc/mei/hw-me.h
index d6567af44377..6022d52af6f6 100644
--- a/drivers/misc/mei/hw-me.h
+++ b/drivers/misc/mei/hw-me.h
@@ -71,8 +71,8 @@ extern const struct mei_cfg mei_me_pch8_sps_cfg;
 struct mei_device *mei_me_dev_init(struct pci_dev *pdev,
 				   const struct mei_cfg *cfg);
 
-int mei_me_pg_set_sync(struct mei_device *dev);
-int mei_me_pg_unset_sync(struct mei_device *dev);
+int mei_me_pg_enter_sync(struct mei_device *dev);
+int mei_me_pg_exit_sync(struct mei_device *dev);
 
 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id);
 irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id);
diff --git a/drivers/misc/mei/hw-txe.c b/drivers/misc/mei/hw-txe.c
index 618ea721aca8..7abafe7d120d 100644
--- a/drivers/misc/mei/hw-txe.c
+++ b/drivers/misc/mei/hw-txe.c
@@ -412,7 +412,7 @@ static void mei_txe_intr_disable(struct mei_device *dev)
 	mei_txe_br_reg_write(hw, HIER_REG, 0);
 }
 /**
- * mei_txe_intr_disable - enable all interrupts
+ * mei_txe_intr_enable - enable all interrupts
  *
  * @dev: the device structure
  */
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index 6ad049a08e4d..97353cf8d9b6 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -389,6 +389,7 @@ void mei_device_init(struct mei_device *dev,
 	INIT_LIST_HEAD(&dev->device_list);
 	INIT_LIST_HEAD(&dev->me_clients);
 	mutex_init(&dev->device_lock);
+	init_rwsem(&dev->me_clients_rwsem);
 	init_waitqueue_head(&dev->wait_hw_ready);
 	init_waitqueue_head(&dev->wait_pg);
 	init_waitqueue_head(&dev->wait_hbm_start);
@@ -396,7 +397,6 @@ void mei_device_init(struct mei_device *dev,
 	dev->dev_state = MEI_DEV_INITIALIZING;
 	dev->reset_count = 0;
 
-	mei_io_list_init(&dev->read_list);
 	mei_io_list_init(&dev->write_list);
 	mei_io_list_init(&dev->write_waiting_list);
 	mei_io_list_init(&dev->ctrl_wr_list);
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 711cddfa9c99..3f84d2edcde4 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -43,7 +43,7 @@ void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *compl_list)
 
 	list_for_each_entry_safe(cb, next, &compl_list->list, list) {
 		cl = cb->cl;
-		list_del(&cb->list);
+		list_del_init(&cb->list);
 
 		dev_dbg(dev->dev, "completing call back.\n");
 		if (cl == &dev->iamthif_cl)
@@ -68,91 +68,91 @@ static inline int mei_cl_hbm_equal(struct mei_cl *cl,
 	return cl->host_client_id == mei_hdr->host_addr &&
 		cl->me_client_id == mei_hdr->me_addr;
 }
+
 /**
- * mei_cl_is_reading - checks if the client
- *		is the one to read this message
- *
- * @cl: mei client
- * @mei_hdr: header of mei message
+ * mei_irq_discard_msg  - discard received message
  *
- * Return: true on match and false otherwise
+ * @dev: mei device
+ * @hdr: message header
  */
-static bool mei_cl_is_reading(struct mei_cl *cl, struct mei_msg_hdr *mei_hdr)
+static inline
+void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
 {
-	return mei_cl_hbm_equal(cl, mei_hdr) &&
-		cl->state == MEI_FILE_CONNECTED &&
-		cl->reading_state != MEI_READ_COMPLETE;
+	/*
+	 * no need to check for size as it is guarantied
+	 * that length fits into rd_msg_buf
+	 */
+	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
+	dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
+		MEI_HDR_PRM(hdr));
 }
 
 /**
  * mei_cl_irq_read_msg - process client message
  *
- * @dev: the device structure
+ * @cl: reading client
  * @mei_hdr: header of mei client message
- * @complete_list: An instance of our list structure
+ * @complete_list: completion list
  *
- * Return: 0 on success, <0 on failure.
+ * Return: always 0
  */
-static int mei_cl_irq_read_msg(struct mei_device *dev,
-			       struct mei_msg_hdr *mei_hdr,
-			       struct mei_cl_cb *complete_list)
+int mei_cl_irq_read_msg(struct mei_cl *cl,
+		       struct mei_msg_hdr *mei_hdr,
+		       struct mei_cl_cb *complete_list)
 {
-	struct mei_cl *cl;
-	struct mei_cl_cb *cb, *next;
+	struct mei_device *dev = cl->dev;
+	struct mei_cl_cb *cb;
 	unsigned char *buffer = NULL;
 
-	list_for_each_entry_safe(cb, next, &dev->read_list.list, list) {
-		cl = cb->cl;
-		if (!mei_cl_is_reading(cl, mei_hdr))
-			continue;
-
-		cl->reading_state = MEI_READING;
+	cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
+	if (!cb) {
+		cl_err(dev, cl, "pending read cb not found\n");
+		goto out;
+	}
 
-		if (cb->response_buffer.size == 0 ||
-		    cb->response_buffer.data == NULL) {
-			cl_err(dev, cl, "response buffer is not allocated.\n");
-			list_del(&cb->list);
-			return -ENOMEM;
-		}
+	if (!mei_cl_is_connected(cl)) {
+		cl_dbg(dev, cl, "not connected\n");
+		cb->status = -ENODEV;
+		goto out;
+	}
 
-		if (cb->response_buffer.size < mei_hdr->length + cb->buf_idx) {
-			cl_dbg(dev, cl, "message overflow. size %d len %d idx %ld\n",
-				cb->response_buffer.size,
-				mei_hdr->length, cb->buf_idx);
-			buffer = krealloc(cb->response_buffer.data,
-					  mei_hdr->length + cb->buf_idx,
-					  GFP_KERNEL);
-
-			if (!buffer) {
-				list_del(&cb->list);
-				return -ENOMEM;
-			}
-			cb->response_buffer.data = buffer;
-			cb->response_buffer.size =
-				mei_hdr->length + cb->buf_idx;
-		}
+	if (cb->buf.size == 0 || cb->buf.data == NULL) {
+		cl_err(dev, cl, "response buffer is not allocated.\n");
+		list_move_tail(&cb->list, &complete_list->list);
+		cb->status = -ENOMEM;
+		goto out;
+	}
 
-		buffer = cb->response_buffer.data + cb->buf_idx;
-		mei_read_slots(dev, buffer, mei_hdr->length);
+	if (cb->buf.size < mei_hdr->length + cb->buf_idx) {
+		cl_dbg(dev, cl, "message overflow. size %d len %d idx %ld\n",
+			cb->buf.size, mei_hdr->length, cb->buf_idx);
+		buffer = krealloc(cb->buf.data, mei_hdr->length + cb->buf_idx,
+				  GFP_KERNEL);
 
-		cb->buf_idx += mei_hdr->length;
-		if (mei_hdr->msg_complete) {
-			cl->status = 0;
-			list_del(&cb->list);
-			cl_dbg(dev, cl, "completed read length = %lu\n",
-				cb->buf_idx);
-			list_add_tail(&cb->list, &complete_list->list);
+		if (!buffer) {
+			cb->status = -ENOMEM;
+			list_move_tail(&cb->list, &complete_list->list);
+			goto out;
 		}
-		break;
+		cb->buf.data = buffer;
+		cb->buf.size = mei_hdr->length + cb->buf_idx;
 	}
 
-	dev_dbg(dev->dev, "message read\n");
-	if (!buffer) {
-		mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
-		dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
-				MEI_HDR_PRM(mei_hdr));
+	buffer = cb->buf.data + cb->buf_idx;
+	mei_read_slots(dev, buffer, mei_hdr->length);
+
+	cb->buf_idx += mei_hdr->length;
+
+	if (mei_hdr->msg_complete) {
+		cb->read_time = jiffies;
+		cl_dbg(dev, cl, "completed read length = %lu\n", cb->buf_idx);
+		list_move_tail(&cb->list, &complete_list->list);
 	}
 
+out:
+	if (!buffer)
+		mei_irq_discard_msg(dev, mei_hdr);
+
 	return 0;
 }
 
@@ -183,7 +183,6 @@ static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	cl->state = MEI_FILE_DISCONNECTED;
 	cl->status = 0;
-	list_del(&cb->list);
 	mei_io_cb_free(cb);
 
 	return ret;
@@ -263,7 +262,7 @@ static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 		return ret;
 	}
 
-	list_move_tail(&cb->list, &dev->read_list.list);
+	list_move_tail(&cb->list, &cl->rd_pending);
 
 	return 0;
 }
@@ -301,7 +300,7 @@ static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
 	if (ret) {
 		cl->status = ret;
 		cb->buf_idx = 0;
-		list_del(&cb->list);
+		list_del_init(&cb->list);
 		return ret;
 	}
 
@@ -378,25 +377,13 @@ int mei_irq_read_handler(struct mei_device *dev,
 		goto end;
 	}
 
-	if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
-	    MEI_FILE_CONNECTED == dev->iamthif_cl.state &&
-	    dev->iamthif_state == MEI_IAMTHIF_READING) {
-
-		ret = mei_amthif_irq_read_msg(dev, mei_hdr, cmpl_list);
-		if (ret) {
-			dev_err(dev->dev, "mei_amthif_irq_read_msg failed = %d\n",
-					ret);
-			goto end;
-		}
+	if (cl == &dev->iamthif_cl) {
+		ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
 	} else {
-		ret = mei_cl_irq_read_msg(dev, mei_hdr, cmpl_list);
-		if (ret) {
-			dev_err(dev->dev, "mei_cl_irq_read_msg failed = %d\n",
-					ret);
-			goto end;
-		}
+		ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
 	}
 
+
 reset_slots:
 	/* reset the number of slots and header */
 	*slots = mei_count_full_read_slots(dev);
@@ -449,21 +436,9 @@ int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 		cl = cb->cl;
 
 		cl->status = 0;
-		list_del(&cb->list);
-		if (cb->fop_type == MEI_FOP_WRITE &&
-		    cl != &dev->iamthif_cl) {
-			cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
-			cl->writing_state = MEI_WRITE_COMPLETE;
-			list_add_tail(&cb->list, &cmpl_list->list);
-		}
-		if (cl == &dev->iamthif_cl) {
-			cl_dbg(dev, cl, "check iamthif flow control.\n");
-			if (dev->iamthif_flow_control_pending) {
-				ret = mei_amthif_irq_read(dev, &slots);
-				if (ret)
-					return ret;
-			}
-		}
+		cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
+		cl->writing_state = MEI_WRITE_COMPLETE;
+		list_move_tail(&cb->list, &cmpl_list->list);
 	}
 
 	if (dev->wd_state == MEI_WD_STOPPING) {
@@ -587,10 +562,7 @@ void mei_timer(struct work_struct *work)
 		if (--dev->iamthif_stall_timer == 0) {
 			dev_err(dev->dev, "timer: amthif  hanged.\n");
 			mei_reset(dev);
-			dev->iamthif_msg_buf_size = 0;
-			dev->iamthif_msg_buf_index = 0;
 			dev->iamthif_canceled = false;
-			dev->iamthif_ioctl = true;
 			dev->iamthif_state = MEI_IAMTHIF_IDLE;
 			dev->iamthif_timer = 0;
 
@@ -636,4 +608,3 @@ out:
 		schedule_delayed_work(&dev->timer_work, 2 * HZ);
 	mutex_unlock(&dev->device_lock);
 }
-
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index 47680c84801c..3e2968159506 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -58,24 +58,18 @@ static int mei_open(struct inode *inode, struct file *file)
 
 	mutex_lock(&dev->device_lock);
 
-	cl = NULL;
-
-	err = -ENODEV;
 	if (dev->dev_state != MEI_DEV_ENABLED) {
 		dev_dbg(dev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
 		    mei_dev_state_str(dev->dev_state));
+		err = -ENODEV;
 		goto err_unlock;
 	}
 
-	err = -ENOMEM;
-	cl = mei_cl_allocate(dev);
-	if (!cl)
-		goto err_unlock;
-
-	/* open_handle_count check is handled in the mei_cl_link */
-	err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-	if (err)
+	cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl)) {
+		err = PTR_ERR(cl);
 		goto err_unlock;
+	}
 
 	file->private_data = cl;
 
@@ -85,7 +79,6 @@ static int mei_open(struct inode *inode, struct file *file)
 
 err_unlock:
 	mutex_unlock(&dev->device_lock);
-	kfree(cl);
 	return err;
 }
 
@@ -100,7 +93,6 @@ err_unlock:
 static int mei_release(struct inode *inode, struct file *file)
 {
 	struct mei_cl *cl = file->private_data;
-	struct mei_cl_cb *cb;
 	struct mei_device *dev;
 	int rets = 0;
 
@@ -114,33 +106,18 @@ static int mei_release(struct inode *inode, struct file *file)
 		rets = mei_amthif_release(dev, file);
 		goto out;
 	}
-	if (cl->state == MEI_FILE_CONNECTED) {
+	if (mei_cl_is_connected(cl)) {
 		cl->state = MEI_FILE_DISCONNECTING;
 		cl_dbg(dev, cl, "disconnecting\n");
 		rets = mei_cl_disconnect(cl);
 	}
-	mei_cl_flush_queues(cl);
+	mei_cl_flush_queues(cl, file);
 	cl_dbg(dev, cl, "removing\n");
 
 	mei_cl_unlink(cl);
 
-
-	/* free read cb */
-	cb = NULL;
-	if (cl->read_cb) {
-		cb = mei_cl_find_read_cb(cl);
-		/* Remove entry from read list */
-		if (cb)
-			list_del(&cb->list);
-
-		cb = cl->read_cb;
-		cl->read_cb = NULL;
-	}
-
 	file->private_data = NULL;
 
-	mei_io_cb_free(cb);
-
 	kfree(cl);
 out:
 	mutex_unlock(&dev->device_lock);
@@ -162,9 +139,8 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 			size_t length, loff_t *offset)
 {
 	struct mei_cl *cl = file->private_data;
-	struct mei_cl_cb *cb_pos = NULL;
-	struct mei_cl_cb *cb = NULL;
 	struct mei_device *dev;
+	struct mei_cl_cb *cb = NULL;
 	int rets;
 	int err;
 
@@ -191,8 +167,8 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		goto out;
 	}
 
-	if (cl->read_cb) {
-		cb = cl->read_cb;
+	cb = mei_cl_read_cb(cl, file);
+	if (cb) {
 		/* read what left */
 		if (cb->buf_idx > *offset)
 			goto copy_buffer;
@@ -208,7 +184,7 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		*offset = 0;
 	}
 
-	err = mei_cl_read_start(cl, length);
+	err = mei_cl_read_start(cl, length, file);
 	if (err && err != -EBUSY) {
 		dev_dbg(dev->dev,
 			"mei start read failure with status = %d\n", err);
@@ -216,8 +192,7 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		goto out;
 	}
 
-	if (MEI_READ_COMPLETE != cl->reading_state &&
-			!waitqueue_active(&cl->rx_wait)) {
+	if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
 		if (file->f_flags & O_NONBLOCK) {
 			rets = -EAGAIN;
 			goto out;
@@ -226,8 +201,8 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		mutex_unlock(&dev->device_lock);
 
 		if (wait_event_interruptible(cl->rx_wait,
-				MEI_READ_COMPLETE == cl->reading_state ||
-				mei_cl_is_transitioning(cl))) {
+				(!list_empty(&cl->rd_completed)) ||
+				(!mei_cl_is_connected(cl)))) {
 
 			if (signal_pending(current))
 				return -EINTR;
@@ -235,26 +210,28 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		}
 
 		mutex_lock(&dev->device_lock);
-		if (mei_cl_is_transitioning(cl)) {
+		if (!mei_cl_is_connected(cl)) {
 			rets = -EBUSY;
 			goto out;
 		}
 	}
 
-	cb = cl->read_cb;
-
+	cb = mei_cl_read_cb(cl, file);
 	if (!cb) {
-		rets = -ENODEV;
-		goto out;
-	}
-	if (cl->reading_state != MEI_READ_COMPLETE) {
 		rets = 0;
 		goto out;
 	}
-	/* now copy the data to user space */
+
 copy_buffer:
+	/* now copy the data to user space */
+	if (cb->status) {
+		rets = cb->status;
+		dev_dbg(dev->dev, "read operation failed %d\n", rets);
+		goto free;
+	}
+
 	dev_dbg(dev->dev, "buf.size = %d buf.idx= %ld\n",
-	    cb->response_buffer.size, cb->buf_idx);
+	    cb->buf.size, cb->buf_idx);
 	if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
 		rets = -EMSGSIZE;
 		goto free;
@@ -264,7 +241,7 @@ copy_buffer:
 	 * however buf_idx may point beyond that */
 	length = min_t(size_t, length, cb->buf_idx - *offset);
 
-	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
+	if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
 		dev_dbg(dev->dev, "failed to copy data to userland\n");
 		rets = -EFAULT;
 		goto free;
@@ -276,13 +253,8 @@ copy_buffer:
 		goto out;
 
 free:
-	cb_pos = mei_cl_find_read_cb(cl);
-	/* Remove entry from read list */
-	if (cb_pos)
-		list_del(&cb_pos->list);
 	mei_io_cb_free(cb);
-	cl->reading_state = MEI_IDLE;
-	cl->read_cb = NULL;
+
 out:
 	dev_dbg(dev->dev, "end mei read rets= %d\n", rets);
 	mutex_unlock(&dev->device_lock);
@@ -336,9 +308,8 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
 		goto out;
 	}
 
-	if (cl->state != MEI_FILE_CONNECTED) {
-		dev_err(dev->dev, "host client = %d,  is not connected to ME client = %d",
-			cl->host_client_id, cl->me_client_id);
+	if (!mei_cl_is_connected(cl)) {
+		cl_err(dev, cl, "is not connected");
 		rets = -ENODEV;
 		goto out;
 	}
@@ -349,41 +320,22 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
 			timeout = write_cb->read_time +
 				mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 
-			if (time_after(jiffies, timeout) ||
-			    cl->reading_state == MEI_READ_COMPLETE) {
+			if (time_after(jiffies, timeout)) {
 				*offset = 0;
-				list_del(&write_cb->list);
 				mei_io_cb_free(write_cb);
 				write_cb = NULL;
 			}
 		}
 	}
 
-	/* free entry used in read */
-	if (cl->reading_state == MEI_READ_COMPLETE) {
-		*offset = 0;
-		write_cb = mei_cl_find_read_cb(cl);
-		if (write_cb) {
-			list_del(&write_cb->list);
-			mei_io_cb_free(write_cb);
-			write_cb = NULL;
-			cl->reading_state = MEI_IDLE;
-			cl->read_cb = NULL;
-		}
-	} else if (cl->reading_state == MEI_IDLE)
-		*offset = 0;
-
-
-	write_cb = mei_io_cb_init(cl, file);
+	*offset = 0;
+	write_cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
 	if (!write_cb) {
 		rets = -ENOMEM;
 		goto out;
 	}
-	rets = mei_io_cb_alloc_req_buf(write_cb, length);
-	if (rets)
-		goto out;
 
-	rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
+	rets = copy_from_user(write_cb->buf.data, ubuf, length);
 	if (rets) {
 		dev_dbg(dev->dev, "failed to copy data from userland\n");
 		rets = -EFAULT;
@@ -391,7 +343,7 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
 	}
 
 	if (cl == &dev->iamthif_cl) {
-		rets = mei_amthif_write(dev, write_cb);
+		rets = mei_amthif_write(cl, write_cb);
 
 		if (rets) {
 			dev_err(dev->dev,
@@ -464,7 +416,7 @@ static int mei_ioctl_connect_client(struct file *file,
 	 */
 	if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
 		dev_dbg(dev->dev, "FW Client is amthi\n");
-		if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
+		if (!mei_cl_is_connected(&dev->iamthif_cl)) {
 			rets = -ENODEV;
 			goto end;
 		}
@@ -588,6 +540,7 @@ static long mei_compat_ioctl(struct file *file,
  */
 static unsigned int mei_poll(struct file *file, poll_table *wait)
 {
+	unsigned long req_events = poll_requested_events(wait);
 	struct mei_cl *cl = file->private_data;
 	struct mei_device *dev;
 	unsigned int mask = 0;
@@ -599,27 +552,26 @@ static unsigned int mei_poll(struct file *file, poll_table *wait)
 
 	mutex_lock(&dev->device_lock);
 
-	if (!mei_cl_is_connected(cl)) {
+
+	if (dev->dev_state != MEI_DEV_ENABLED ||
+	    !mei_cl_is_connected(cl)) {
 		mask = POLLERR;
 		goto out;
 	}
 
-	mutex_unlock(&dev->device_lock);
-
-
-	if (cl == &dev->iamthif_cl)
-		return mei_amthif_poll(dev, file, wait);
-
-	poll_wait(file, &cl->tx_wait, wait);
-
-	mutex_lock(&dev->device_lock);
-
-	if (!mei_cl_is_connected(cl)) {
-		mask = POLLERR;
+	if (cl == &dev->iamthif_cl) {
+		mask = mei_amthif_poll(dev, file, wait);
 		goto out;
 	}
 
-	mask |= (POLLIN | POLLRDNORM);
+	if (req_events & (POLLIN | POLLRDNORM)) {
+		poll_wait(file, &cl->rx_wait, wait);
+
+		if (!list_empty(&cl->rd_completed))
+			mask |= POLLIN | POLLRDNORM;
+		else
+			mei_cl_read_start(cl, 0, file);
+	}
 
 out:
 	mutex_unlock(&dev->device_lock);
diff --git a/drivers/misc/mei/mei-trace.c b/drivers/misc/mei/mei-trace.c
new file mode 100644
index 000000000000..388efb519138
--- /dev/null
+++ b/drivers/misc/mei/mei-trace.c
@@ -0,0 +1,25 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+#include <linux/module.h>
+
+/* sparse doesn't like tracepoint macros */
+#ifndef __CHECKER__
+#define CREATE_TRACE_POINTS
+#include "mei-trace.h"
+
+EXPORT_TRACEPOINT_SYMBOL(mei_reg_read);
+EXPORT_TRACEPOINT_SYMBOL(mei_reg_write);
+#endif /* __CHECKER__ */
diff --git a/drivers/misc/mei/mei-trace.h b/drivers/misc/mei/mei-trace.h
new file mode 100644
index 000000000000..47e1bc6551d4
--- /dev/null
+++ b/drivers/misc/mei/mei-trace.h
@@ -0,0 +1,74 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#if !defined(_MEI_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
+#define _MEI_TRACE_H_
+
+#include <linux/stringify.h>
+#include <linux/types.h>
+#include <linux/tracepoint.h>
+
+#include <linux/device.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mei
+
+TRACE_EVENT(mei_reg_read,
+	TP_PROTO(const struct device *dev, const char *reg, u32 offs, u32 val),
+	TP_ARGS(dev, reg, offs, val),
+	TP_STRUCT__entry(
+		__string(dev, dev_name(dev))
+		__field(const char *, reg)
+		__field(u32, offs)
+		__field(u32, val)
+	),
+	TP_fast_assign(
+		__assign_str(dev, dev_name(dev))
+		__entry->reg  = reg;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%s] read %s:[%#x] = %#x",
+		  __get_str(dev), __entry->reg, __entry->offs, __entry->val)
+);
+
+TRACE_EVENT(mei_reg_write,
+	TP_PROTO(const struct device *dev, const char *reg, u32 offs, u32 val),
+	TP_ARGS(dev, reg, offs, val),
+	TP_STRUCT__entry(
+		__string(dev, dev_name(dev))
+		__field(const char *, reg)
+		__field(u32, offs)
+		__field(u32, val)
+	),
+	TP_fast_assign(
+		__assign_str(dev, dev_name(dev))
+		__entry->reg = reg;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%s] write %s[%#x] = %#x)",
+		  __get_str(dev), __entry->reg,  __entry->offs, __entry->val)
+);
+
+#endif /* _MEI_TRACE_H_ */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE mei-trace
+#include <trace/define_trace.h>
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 6c6ce9381535..f066ecd71939 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -194,23 +194,25 @@ struct mei_cl;
  * @list: link in callback queue
  * @cl: file client who is running this operation
  * @fop_type: file operation type
- * @request_buffer: buffer to store request data
- * @response_buffer: buffer to store response data
+ * @buf: buffer for data associated with the callback
  * @buf_idx: last read index
  * @read_time: last read operation time stamp (iamthif)
  * @file_object: pointer to file structure
+ * @status: io status of the cb
  * @internal: communication between driver and FW flag
+ * @completed: the transfer or reception has completed
  */
 struct mei_cl_cb {
 	struct list_head list;
 	struct mei_cl *cl;
 	enum mei_cb_file_ops fop_type;
-	struct mei_msg_data request_buffer;
-	struct mei_msg_data response_buffer;
+	struct mei_msg_data buf;
 	unsigned long buf_idx;
 	unsigned long read_time;
 	struct file *file_object;
+	int status;
 	u32 internal:1;
+	u32 completed:1;
 };
 
 /**
@@ -229,9 +231,9 @@ struct mei_cl_cb {
  * @me_client_id: me/fw id
  * @mei_flow_ctrl_creds: transmit flow credentials
  * @timer_count:  watchdog timer for operation completion
- * @reading_state: state of the rx
  * @writing_state: state of the tx
- * @read_cb: current pending reading callback
+ * @rd_pending: pending read credits
+ * @rd_completed: completed read
  *
  * @device: device on the mei client bus
  * @device_link:  link to bus clients
@@ -249,9 +251,9 @@ struct mei_cl {
 	u8 me_client_id;
 	u8 mei_flow_ctrl_creds;
 	u8 timer_count;
-	enum mei_file_transaction_states reading_state;
 	enum mei_file_transaction_states writing_state;
-	struct mei_cl_cb *read_cb;
+	struct list_head rd_pending;
+	struct list_head rd_completed;
 
 	/* MEI CL bus data */
 	struct mei_cl_device *device;
@@ -423,7 +425,6 @@ const char *mei_pg_state_str(enum mei_pg_state state);
  * @cdev        : character device
  * @minor       : minor number allocated for device
  *
- * @read_list   : read completion list
  * @write_list  : write pending list
  * @write_waiting_list : write completion list
  * @ctrl_wr_list : pending control write list
@@ -460,6 +461,7 @@ const char *mei_pg_state_str(enum mei_pg_state state);
  * @version     : HBM protocol version in use
  * @hbm_f_pg_supported : hbm feature pgi protocol
  *
+ * @me_clients_rwsem: rw lock over me_clients list
  * @me_clients  : list of FW clients
  * @me_clients_map : FW clients bit map
  * @host_clients_map : host clients id pool
@@ -480,12 +482,7 @@ const char *mei_pg_state_str(enum mei_pg_state state);
  * @iamthif_mtu : amthif client max message length
  * @iamthif_timer : time stamp of current amthif command completion
  * @iamthif_stall_timer : timer to detect amthif hang
- * @iamthif_msg_buf : amthif current message buffer
- * @iamthif_msg_buf_size : size of current amthif message request buffer
- * @iamthif_msg_buf_index : current index in amthif message request buffer
  * @iamthif_state : amthif processor state
- * @iamthif_flow_control_pending: amthif waits for flow control
- * @iamthif_ioctl : wait for completion if amthif control message
  * @iamthif_canceled : current amthif command is canceled
  *
  * @init_work   : work item for the device init
@@ -503,7 +500,6 @@ struct mei_device {
 	struct cdev cdev;
 	int minor;
 
-	struct mei_cl_cb read_list;
 	struct mei_cl_cb write_list;
 	struct mei_cl_cb write_waiting_list;
 	struct mei_cl_cb ctrl_wr_list;
@@ -556,6 +552,7 @@ struct mei_device {
 	struct hbm_version version;
 	unsigned int hbm_f_pg_supported:1;
 
+	struct rw_semaphore me_clients_rwsem;
 	struct list_head me_clients;
 	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
 	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
@@ -579,12 +576,7 @@ struct mei_device {
 	int iamthif_mtu;
 	unsigned long iamthif_timer;
 	u32 iamthif_stall_timer;
-	unsigned char *iamthif_msg_buf; /* Note: memory has to be allocated */
-	u32 iamthif_msg_buf_size;
-	u32 iamthif_msg_buf_index;
 	enum iamthif_states iamthif_state;
-	bool iamthif_flow_control_pending;
-	bool iamthif_ioctl;
 	bool iamthif_canceled;
 
 	struct work_struct init_work;
@@ -662,8 +654,6 @@ void mei_amthif_reset_params(struct mei_device *dev);
 
 int mei_amthif_host_init(struct mei_device *dev);
 
-int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *priv_cb);
-
 int mei_amthif_read(struct mei_device *dev, struct file *file,
 		char __user *ubuf, size_t length, loff_t *offset);
 
@@ -675,13 +665,13 @@ int mei_amthif_release(struct mei_device *dev, struct file *file);
 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
 						struct file *file);
 
-void mei_amthif_run_next_cmd(struct mei_device *dev);
-
+int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
+int mei_amthif_run_next_cmd(struct mei_device *dev);
 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 			struct mei_cl_cb *cmpl_list);
 
 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb);
-int mei_amthif_irq_read_msg(struct mei_device *dev,
+int mei_amthif_irq_read_msg(struct mei_cl *cl,
 			    struct mei_msg_hdr *mei_hdr,
 			    struct mei_cl_cb *complete_list);
 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
diff --git a/drivers/misc/mei/nfc.c b/drivers/misc/mei/nfc.c
index bb61a119b8bb..c3bcb63686d7 100644
--- a/drivers/misc/mei/nfc.c
+++ b/drivers/misc/mei/nfc.c
@@ -482,8 +482,8 @@ err:
 int mei_nfc_host_init(struct mei_device *dev)
 {
 	struct mei_nfc_dev *ndev;
-	struct mei_cl *cl_info, *cl = NULL;
-	struct mei_me_client *me_cl;
+	struct mei_cl *cl_info, *cl;
+	struct mei_me_client *me_cl = NULL;
 	int ret;
 
 
@@ -500,17 +500,6 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
-	ndev->cl_info = mei_cl_allocate(dev);
-	ndev->cl = mei_cl_allocate(dev);
-
-	cl = ndev->cl;
-	cl_info = ndev->cl_info;
-
-	if (!cl || !cl_info) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
 	/* check for valid client id */
 	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_info_guid);
 	if (!me_cl) {
@@ -519,17 +508,21 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
+	cl_info = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl_info)) {
+		ret = PTR_ERR(cl_info);
+		goto err;
+	}
+
 	cl_info->me_client_id = me_cl->client_id;
 	cl_info->cl_uuid = me_cl->props.protocol_name;
 	mei_me_cl_put(me_cl);
-
-	ret = mei_cl_link(cl_info, MEI_HOST_CLIENT_ID_ANY);
-	if (ret)
-		goto err;
-
+	me_cl = NULL;
 
 	list_add_tail(&cl_info->device_link, &dev->device_list);
 
+	ndev->cl_info = cl_info;
+
 	/* check for valid client id */
 	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
 	if (!me_cl) {
@@ -538,16 +531,21 @@ int mei_nfc_host_init(struct mei_device *dev)
 		goto err;
 	}
 
+	cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+	if (IS_ERR(cl)) {
+		ret = PTR_ERR(cl);
+		goto err;
+	}
+
 	cl->me_client_id = me_cl->client_id;
 	cl->cl_uuid = me_cl->props.protocol_name;
 	mei_me_cl_put(me_cl);
-
-	ret = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-	if (ret)
-		goto err;
+	me_cl = NULL;
 
 	list_add_tail(&cl->device_link, &dev->device_list);
 
+	ndev->cl = cl;
+
 	ndev->req_id = 1;
 
 	INIT_WORK(&ndev->init_work, mei_nfc_init);
@@ -557,6 +555,7 @@ int mei_nfc_host_init(struct mei_device *dev)
 	return 0;
 
 err:
+	mei_me_cl_put(me_cl);
 	mei_nfc_free(ndev);
 
 	return ret;
diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c
index af44ee26075d..23f71f5ce4fb 100644
--- a/drivers/misc/mei/pci-me.c
+++ b/drivers/misc/mei/pci-me.c
@@ -388,7 +388,7 @@ static int mei_me_pm_runtime_suspend(struct device *device)
 	mutex_lock(&dev->device_lock);
 
 	if (mei_write_is_idle(dev))
-		ret = mei_me_pg_set_sync(dev);
+		ret = mei_me_pg_enter_sync(dev);
 	else
 		ret = -EAGAIN;
 
@@ -413,7 +413,7 @@ static int mei_me_pm_runtime_resume(struct device *device)
 
 	mutex_lock(&dev->device_lock);
 
-	ret = mei_me_pg_unset_sync(dev);
+	ret = mei_me_pg_exit_sync(dev);
 
 	mutex_unlock(&dev->device_lock);
 
diff --git a/drivers/misc/mei/pci-txe.c b/drivers/misc/mei/pci-txe.c
index c86e2ddbe30a..dcfcba44b6f7 100644
--- a/drivers/misc/mei/pci-txe.c
+++ b/drivers/misc/mei/pci-txe.c
@@ -63,7 +63,7 @@ static void mei_txe_pci_iounmap(struct pci_dev *pdev, struct mei_txe_hw *hw)
 	}
 }
 /**
- * mei_probe - Device Initialization Routine
+ * mei_txe_probe - Device Initialization Routine
  *
  * @pdev: PCI device structure
  * @ent: entry in mei_txe_pci_tbl
@@ -193,7 +193,7 @@ end:
 }
 
 /**
- * mei_remove - Device Removal Routine
+ * mei_txe_remove - Device Removal Routine
  *
  * @pdev: PCI device structure
  *
diff --git a/drivers/misc/mei/wd.c b/drivers/misc/mei/wd.c
index 475f1dea45bf..2725f865c3d6 100644
--- a/drivers/misc/mei/wd.c
+++ b/drivers/misc/mei/wd.c
@@ -160,9 +160,10 @@ int mei_wd_send(struct mei_device *dev)
  */
 int mei_wd_stop(struct mei_device *dev)
 {
+	struct mei_cl *cl = &dev->wd_cl;
 	int ret;
 
-	if (dev->wd_cl.state != MEI_FILE_CONNECTED ||
+	if (!mei_cl_is_connected(cl) ||
 	    dev->wd_state != MEI_WD_RUNNING)
 		return 0;
 
@@ -170,7 +171,7 @@ int mei_wd_stop(struct mei_device *dev)
 
 	dev->wd_state = MEI_WD_STOPPING;
 
-	ret = mei_cl_flow_ctrl_creds(&dev->wd_cl);
+	ret = mei_cl_flow_ctrl_creds(cl);
 	if (ret < 0)
 		goto err;
 
@@ -202,22 +203,25 @@ err:
 	return ret;
 }
 
-/*
+/**
  * mei_wd_ops_start - wd start command from the watchdog core.
  *
- * @wd_dev - watchdog device struct
+ * @wd_dev: watchdog device struct
  *
  * Return: 0 if success, negative errno code for failure
  */
 static int mei_wd_ops_start(struct watchdog_device *wd_dev)
 {
-	int err = -ENODEV;
 	struct mei_device *dev;
+	struct mei_cl *cl;
+	int err = -ENODEV;
 
 	dev = watchdog_get_drvdata(wd_dev);
 	if (!dev)
 		return -ENODEV;
 
+	cl = &dev->wd_cl;
+
 	mutex_lock(&dev->device_lock);
 
 	if (dev->dev_state != MEI_DEV_ENABLED) {
@@ -226,8 +230,8 @@ static int mei_wd_ops_start(struct watchdog_device *wd_dev)
 		goto end_unlock;
 	}
 
-	if (dev->wd_cl.state != MEI_FILE_CONNECTED)	{
-		dev_dbg(dev->dev, "MEI Driver is not connected to Watchdog Client\n");
+	if (!mei_cl_is_connected(cl)) {
+		cl_dbg(dev, cl, "MEI Driver is not connected to Watchdog Client\n");
 		goto end_unlock;
 	}
 
@@ -239,10 +243,10 @@ end_unlock:
 	return err;
 }
 
-/*
+/**
  * mei_wd_ops_stop -  wd stop command from the watchdog core.
  *
- * @wd_dev - watchdog device struct
+ * @wd_dev: watchdog device struct
  *
  * Return: 0 if success, negative errno code for failure
  */
@@ -261,10 +265,10 @@ static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
 	return 0;
 }
 
-/*
+/**
  * mei_wd_ops_ping - wd ping command from the watchdog core.
  *
- * @wd_dev - watchdog device struct
+ * @wd_dev: watchdog device struct
  *
  * Return: 0 if success, negative errno code for failure
  */
@@ -282,8 +286,8 @@ static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
 
 	mutex_lock(&dev->device_lock);
 
-	if (cl->state != MEI_FILE_CONNECTED) {
-		dev_err(dev->dev, "wd: not connected.\n");
+	if (!mei_cl_is_connected(cl)) {
+		cl_err(dev, cl, "wd: not connected.\n");
 		ret = -ENODEV;
 		goto end;
 	}
@@ -311,11 +315,11 @@ end:
 	return ret;
 }
 
-/*
+/**
  * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
  *
- * @wd_dev - watchdog device struct
- * @timeout - timeout value to set
+ * @wd_dev: watchdog device struct
+ * @timeout: timeout value to set
  *
  * Return: 0 if success, negative errno code for failure
  */