diff --git a/drivers/misc/mei/amthif.c b/drivers/misc/mei/amthif.c
index e7ba8801d2b4..bff9a07f1af5 100644
--- a/drivers/misc/mei/amthif.c
+++ b/drivers/misc/mei/amthif.c
@@ -436,23 +436,23 @@ unsigned int mei_amthif_poll(struct mei_device *dev,
 
 
 /**
- * mei_amthif_irq_write_completed - processes completed iamthif operation.
+ * mei_amthif_irq_write - write iamthif command in irq thread context.
  *
  * @dev: the device structure.
- * @slots: free slots.
  * @cb_pos: callback block.
  * @cl: private data of the file object.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise, error.
  */
-int mei_amthif_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
-				  s32 *slots, struct mei_cl_cb *cmpl_list)
+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);
@@ -469,13 +469,15 @@ int mei_amthif_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 	mei_hdr.reserved = 0;
 	mei_hdr.internal = 0;
 
-	if (*slots >= msg_slots) {
+	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);
+	} 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 {
@@ -485,7 +487,6 @@ int mei_amthif_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	dev_dbg(&dev->pdev->dev, MEI_HDR_FMT,  MEI_HDR_PRM(&mei_hdr));
 
-	*slots -=  msg_slots;
 	rets = mei_write_message(dev, &mei_hdr,
 			dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
 	if (rets) {
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 083179b75297..2b0f99955ba6 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -698,27 +698,26 @@ err:
 }
 
 /**
- * mei_cl_irq_write_complete - write a message to device
+ * mei_cl_irq_write - write a message to device
  *	from the interrupt thread context
  *
  * @cl: client
  * @cb: callback block.
- * @slots: free slots.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise error.
  */
-int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
-				     s32 *slots, struct mei_cl_cb *cmpl_list)
+int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
+		     struct mei_cl_cb *cmpl_list)
 {
 	struct mei_device *dev;
 	struct mei_msg_data *buf;
 	struct mei_msg_hdr mei_hdr;
 	size_t len;
 	u32 msg_slots;
+	int slots;
 	int rets;
 
-
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
 
@@ -735,6 +734,7 @@ int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 		return 0;
 	}
 
+	slots = mei_hbuf_empty_slots(dev);
 	len = buf->size - cb->buf_idx;
 	msg_slots = mei_data2slots(len);
 
@@ -743,13 +743,13 @@ int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 	mei_hdr.reserved = 0;
 	mei_hdr.internal = cb->internal;
 
-	if (*slots >= msg_slots) {
+	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);
+	} 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 {
@@ -760,7 +760,6 @@ int mei_cl_irq_write_complete(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);
 
-	*slots -=  msg_slots;
 	rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
 	if (rets) {
 		cl->status = rets;
diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h
index c8396e582f1c..c11b663358a4 100644
--- a/drivers/misc/mei/client.h
+++ b/drivers/misc/mei/client.h
@@ -102,8 +102,8 @@ 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_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking);
-int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
-				s32 *slots, struct mei_cl_cb *cmpl_list);
+int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
+		     struct mei_cl_cb *cmpl_list);
 
 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb);
 
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index b0c42d6182a6..84165cce57d2 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -354,7 +354,7 @@ static int mei_me_write_message(struct mei_device *dev,
 
 	dw_cnt = mei_data2slots(length);
 	if (empty_slots < 0 || dw_cnt > empty_slots)
-		return -EIO;
+		return -EMSGSIZE;
 
 	mei_me_reg_write(hw, H_CB_WW, *((u32 *) header));
 
diff --git a/drivers/misc/mei/hw-txe.c b/drivers/misc/mei/hw-txe.c
index 8f5e4be9ebc2..f60182a52f96 100644
--- a/drivers/misc/mei/hw-txe.c
+++ b/drivers/misc/mei/hw-txe.c
@@ -566,7 +566,9 @@ static int mei_txe_write(struct mei_device *dev,
 	struct mei_txe_hw *hw = to_txe_hw(dev);
 	unsigned long rem;
 	unsigned long length;
+	int slots = dev->hbuf_depth;
 	u32 *reg_buf = (u32 *)buf;
+	u32 dw_cnt;
 	int i;
 
 	if (WARN_ON(!header || !buf))
@@ -576,11 +578,9 @@ static int mei_txe_write(struct mei_device *dev,
 
 	dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header));
 
-	if ((length + sizeof(struct mei_msg_hdr)) > PAYLOAD_SIZE) {
-		dev_err(&dev->pdev->dev, "write length exceeded = %ld > %d\n",
-			length + sizeof(struct mei_msg_hdr), PAYLOAD_SIZE);
-		return -ERANGE;
-	}
+	dw_cnt = mei_data2slots(length);
+	if (dw_cnt > slots)
+		return -EMSGSIZE;
 
 	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
 		return -EAGAIN;
@@ -605,6 +605,9 @@ static int mei_txe_write(struct mei_device *dev,
 		mei_txe_input_payload_write(dev, i + 1, reg);
 	}
 
+	/* after each write the whole buffer is consumed */
+	hw->slots = 0;
+
 	/* Set Input-Doorbell */
 	mei_txe_input_doorbell_set(hw);
 
@@ -632,7 +635,8 @@ static size_t mei_txe_hbuf_max_len(const struct mei_device *dev)
  */
 static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
 {
-	return dev->hbuf_depth;
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	return hw->slots;
 }
 
 /**
@@ -978,11 +982,12 @@ irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
 		}
 	}
 	/* Input Ready: Detection if host can write to SeC */
-	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause))
+	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
 		dev->hbuf_is_ready = true;
+		hw->slots = dev->hbuf_depth;
+	}
 
 	if (hw->aliveness && dev->hbuf_is_ready) {
-
 		/* get the real register value */
 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
 		rets = mei_irq_write_handler(dev, &complete_list);
diff --git a/drivers/misc/mei/hw-txe.h b/drivers/misc/mei/hw-txe.h
index fdb665f44d5d..0812d98633a4 100644
--- a/drivers/misc/mei/hw-txe.h
+++ b/drivers/misc/mei/hw-txe.h
@@ -46,6 +46,7 @@ struct mei_txe_hw {
 	void __iomem *mem_addr[NUM_OF_MEM_BARS];
 	u32 aliveness;
 	u32 readiness;
+	u32 slots;
 
 	wait_queue_head_t wait_aliveness;
 	bool recvd_aliveness;
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index aed03efa72f4..e6151e2dac48 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -165,25 +165,24 @@ static int mei_cl_irq_read_msg(struct mei_device *dev,
  *
  * @cl: client
  * @cb: callback block.
- * @slots: free slots.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise, error.
  */
 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
-			s32 *slots, struct mei_cl_cb *cmpl_list)
+				     struct mei_cl_cb *cmpl_list)
 {
 	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
 	int ret;
 
-	u32 msg_slots =
-		mei_data2slots(sizeof(struct hbm_client_connect_response));
+	slots = mei_hbuf_empty_slots(dev);
+	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
 
-	if (*slots < msg_slots)
+	if (slots < msg_slots)
 		return -EMSGSIZE;
 
-	*slots -= msg_slots;
-
 	ret = mei_hbm_cl_disconnect_rsp(dev, cl);
 
 	cl->state = MEI_FILE_DISCONNECTED;
@@ -201,24 +200,23 @@ static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
  *
  * @cl: client
  * @cb: callback block.
- * @slots: free slots.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise, error.
  */
 static int mei_cl_irq_close(struct mei_cl *cl, struct mei_cl_cb *cb,
-			s32 *slots, struct mei_cl_cb *cmpl_list)
+			    struct mei_cl_cb *cmpl_list)
 {
 	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
 
-	u32 msg_slots =
-		mei_data2slots(sizeof(struct hbm_client_connect_request));
+	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
+	slots = mei_hbuf_empty_slots(dev);
 
-	if (*slots < msg_slots)
+	if (slots < msg_slots)
 		return -EMSGSIZE;
 
-	*slots -= msg_slots;
-
 	if (mei_hbm_cl_disconnect_req(dev, cl)) {
 		cl->status = 0;
 		cb->buf_idx = 0;
@@ -242,27 +240,23 @@ static int mei_cl_irq_close(struct mei_cl *cl, struct mei_cl_cb *cb,
  *
  * @cl: client
  * @cb: callback block.
- * @slots: free slots.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise, error.
  */
 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
-			   s32 *slots, struct mei_cl_cb *cmpl_list)
+			   struct mei_cl_cb *cmpl_list)
 {
 	struct mei_device *dev = cl->dev;
-	u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
-
+	u32 msg_slots;
+	int slots;
 	int ret;
 
+	msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
+	slots = mei_hbuf_empty_slots(dev);
 
-	if (*slots < msg_slots) {
-		/* return the cancel routine */
-		list_del(&cb->list);
+	if (slots < msg_slots)
 		return -EMSGSIZE;
-	}
-
-	*slots -= msg_slots;
 
 	ret = mei_hbm_cl_flow_control_req(dev, cl);
 	if (ret) {
@@ -283,30 +277,26 @@ static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
  *
  * @cl: client
  * @cb: callback block.
- * @slots: free slots.
  * @cmpl_list: complete list.
  *
  * returns 0, OK; otherwise, error.
  */
 static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
-			   s32 *slots, struct mei_cl_cb *cmpl_list)
+			      struct mei_cl_cb *cmpl_list)
 {
 	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
 	int ret;
 
-	u32 msg_slots =
-		mei_data2slots(sizeof(struct hbm_client_connect_request));
+	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
+	slots = mei_hbuf_empty_slots(dev);
 
 	if (mei_cl_is_other_connecting(cl))
 		return 0;
 
-	if (*slots < msg_slots) {
-		/* return the cancel routine */
-		list_del(&cb->list);
+	if (slots < msg_slots)
 		return -EMSGSIZE;
-	}
-
-	*slots -=  msg_slots;
 
 	cl->state = MEI_FILE_CONNECTING;
 
@@ -494,13 +484,7 @@ int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 				dev_dbg(&dev->pdev->dev, "wd send failed.\n");
 			else if (mei_cl_flow_ctrl_reduce(&dev->wd_cl))
 				return -ENODEV;
-
 			dev->wd_pending = false;
-
-			if (dev->wd_state == MEI_WD_RUNNING)
-				slots -= mei_data2slots(MEI_WD_START_MSG_SIZE);
-			else
-				slots -= mei_data2slots(MEI_WD_STOP_MSG_SIZE);
 		}
 	}
 
@@ -515,28 +499,28 @@ int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 		switch (cb->fop_type) {
 		case MEI_FOP_CLOSE:
 			/* send disconnect message */
-			ret = mei_cl_irq_close(cl, cb, &slots, cmpl_list);
+			ret = mei_cl_irq_close(cl, cb, cmpl_list);
 			if (ret)
 				return ret;
 
 			break;
 		case MEI_FOP_READ:
 			/* send flow control message */
-			ret = mei_cl_irq_read(cl, cb, &slots, cmpl_list);
+			ret = mei_cl_irq_read(cl, cb, cmpl_list);
 			if (ret)
 				return ret;
 
 			break;
 		case MEI_FOP_CONNECT:
 			/* connect message */
-			ret = mei_cl_irq_connect(cl, cb, &slots, cmpl_list);
+			ret = mei_cl_irq_connect(cl, cb, cmpl_list);
 			if (ret)
 				return ret;
 
 			break;
 		case MEI_FOP_DISCONNECT_RSP:
 			/* send disconnect resp */
-			ret = mei_cl_irq_disconnect_rsp(cl, cb, &slots, cmpl_list);
+			ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
 			if (ret)
 				return ret;
 		default:
@@ -551,11 +535,9 @@ int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 		if (cl == NULL)
 			continue;
 		if (cl == &dev->iamthif_cl)
-			ret = mei_amthif_irq_write_complete(cl, cb,
-						&slots, cmpl_list);
+			ret = mei_amthif_irq_write(cl, cb, cmpl_list);
 		else
-			ret = mei_cl_irq_write_complete(cl, cb,
-						&slots, cmpl_list);
+			ret = mei_cl_irq_write(cl, cb, cmpl_list);
 		if (ret)
 			return ret;
 	}
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 52499bc5a068..36640b9d54c5 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -515,8 +515,8 @@ struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
 
 void mei_amthif_run_next_cmd(struct mei_device *dev);
 
-int mei_amthif_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
-				  s32 *slots, struct mei_cl_cb *cmpl_list);
+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,