Initial import

1 files changed, 1360 insertions, 0 deletions

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
new file mode 100644
index 000000000..b2b9f4382
--- /dev/null
+++ b/drivers/misc/mei/client.c
@@ -0,0 +1,1360 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, 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/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+/**
+ * mei_me_cl_init - initialize me client
+ *
+ * @me_cl: me client
+ */
+void mei_me_cl_init(struct mei_me_client *me_cl)
+{
+	INIT_LIST_HEAD(&me_cl->list);
+	kref_init(&me_cl->refcnt);
+}
+
+/**
+ * mei_me_cl_get - increases me client refcount
+ *
+ * @me_cl: me client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: me client or NULL
+ */
+struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
+{
+	if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
+		return me_cl;
+
+	return NULL;
+}
+
+/**
+ * mei_me_cl_release - free me client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @ref: me_client refcount
+ */
+static void mei_me_cl_release(struct kref *ref)
+{
+	struct mei_me_client *me_cl =
+		container_of(ref, struct mei_me_client, refcnt);
+
+	kfree(me_cl);
+}
+
+/**
+ * mei_me_cl_put - decrease me client refcount and free client if necessary
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @me_cl: me client
+ */
+void mei_me_cl_put(struct mei_me_client *me_cl)
+{
+	if (me_cl)
+		kref_put(&me_cl->refcnt, mei_me_cl_release);
+}
+
+/**
+ * __mei_me_cl_del  - delete me client 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
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *pn;
+
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0)
+			return mei_me_cl_get(me_cl);
+	}
+
+	return NULL;
+}
+
+/**
+ * mei_me_cl_by_uuid - locate me client by uuid
+ *	increases ref count
+ *
+ * @dev: mei device
+ * @uuid: me client uuid
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
+					const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * mei_me_cl_by_id - locate me client by client id
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @client_id: me client id
+ *
+ * Return: me client or NULL if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
+{
+
+	struct mei_me_client *__me_cl, *me_cl = NULL;
+
+	down_read(&dev->me_clients_rwsem);
+	list_for_each_entry(__me_cl, &dev->me_clients, list) {
+		if (__me_cl->client_id == client_id) {
+			me_cl = mei_me_cl_get(__me_cl);
+			break;
+		}
+	}
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @client_id: me client id
+ *
+ * Return: me client or null if not found
+ *
+ * Locking: dev->me_clients_rwsem
+ */
+static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *pn;
+
+	WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
+
+	list_for_each_entry(me_cl, &dev->me_clients, list) {
+		pn = &me_cl->props.protocol_name;
+		if (uuid_le_cmp(*uuid, *pn) == 0 &&
+		    me_cl->client_id == client_id)
+			return mei_me_cl_get(me_cl);
+	}
+
+	return NULL;
+}
+
+
+/**
+ * mei_me_cl_by_uuid_id - locate me client by client id and uuid
+ *	increases ref count
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @client_id: me client id
+ *
+ * Return: me client or null if not found
+ */
+struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
+					   const uuid_le *uuid, u8 client_id)
+{
+	struct mei_me_client *me_cl;
+
+	down_read(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
+	up_read(&dev->me_clients_rwsem);
+
+	return me_cl;
+}
+
+/**
+ * mei_me_cl_rm_by_uuid - remove all me clients matching uuid
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
+{
+	struct mei_me_client *me_cl;
+
+	dev_dbg(dev->dev, "remove %pUl\n", uuid);
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid(dev, uuid);
+	__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
+ *
+ * @dev: the device structure
+ * @uuid: me client uuid
+ * @id: me client id
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
+{
+	struct mei_me_client *me_cl;
+
+	dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
+
+	down_write(&dev->me_clients_rwsem);
+	me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
+	__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_me_cl_rm_all - remove all me clients
+ *
+ * @dev: the device structure
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_me_cl_rm_all(struct mei_device *dev)
+{
+	struct mei_me_client *me_cl, *next;
+
+	down_write(&dev->me_clients_rwsem);
+	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
+		__mei_me_cl_del(dev, me_cl);
+	up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * mei_cl_cmp_id - tells if the clients are the same
+ *
+ * @cl1: host client 1
+ * @cl2: host client 2
+ *
+ * Return: true  - if the clients has same host and me ids
+ *         false - otherwise
+ */
+static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
+				const struct mei_cl *cl2)
+{
+	return cl1 && cl2 &&
+		(cl1->host_client_id == cl2->host_client_id) &&
+		(cl1->me_client_id == cl2->me_client_id);
+}
+
+/**
+ * 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
+ * @free:  whether to free the cbs
+ */
+static void __mei_io_list_flush(struct mei_cl_cb *list,
+				struct mei_cl *cl, bool free)
+{
+	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_init(&cb->list);
+			if (free)
+				mei_io_cb_free(cb);
+		}
+	}
+}
+
+/**
+ * mei_io_list_flush - removes list entry belonging to cl.
+ *
+ * @list:  An instance of our list structure
+ * @cl: host client
+ */
+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
+ *
+ * @list:  An instance of our list structure
+ * @cl: host client
+ */
+static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
+{
+	__mei_io_list_flush(list, cl, true);
+}
+
+/**
+ * mei_io_cb_alloc_buf - allocate callback buffer
+ *
+ * @cb: io callback structure
+ * @length: size of the buffer
+ *
+ * Return: 0 on success
+ *         -EINVAL if cb is NULL
+ *         -ENOMEM if allocation failed
+ */
+int mei_io_cb_alloc_buf(struct mei_cl_cb *cb, size_t length)
+{
+	if (!cb)
+		return -EINVAL;
+
+	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_cl_alloc_cb - a convenient wrapper for allocating read cb
+ *
+ * @cl: host client
+ * @length: size of the buffer
+ * @type: operation type
+ * @fp: associated file pointer (might be NULL)
+ *
+ * Return: cb on success and NULL on failure
+ */
+struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
+				  enum mei_cb_file_ops type, struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	cb = mei_io_cb_init(cl, type, fp);
+	if (!cb)
+		return NULL;
+
+	if (mei_io_cb_alloc_buf(cb, length)) {
+		mei_io_cb_free(cb);
+		return NULL;
+	}
+
+	return cb;
+}
+
+/**
+ * mei_cl_read_cb - find this cl's callback in the read list
+ *     for a specific file
+ *
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ *
+ * Return: cb on success, NULL if cb is not found
+ */
+struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
+{
+	struct mei_cl_cb *cb;
+
+	list_for_each_entry(cb, &cl->rd_completed, list)
+		if (!fp || fp == cb->file_object)
+			return cb;
+
+	return NULL;
+}
+
+/**
+ * mei_cl_read_cb_flush - free client's read pending and completed cbs
+ *   for a specific file
+ *
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ */
+void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
+{
+	struct mei_cl_cb *cb, *next;
+
+	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, const struct file *fp)
+{
+	struct mei_device *dev;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "remove list entry belonging to cl\n");
+	mei_io_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;
+}
+
+
+/**
+ * mei_cl_init - initializes cl.
+ *
+ * @cl: host client to be initialized
+ * @dev: mei device
+ */
+void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
+{
+	memset(cl, 0, sizeof(struct mei_cl));
+	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->writing_state = MEI_IDLE;
+	cl->dev = dev;
+}
+
+/**
+ * mei_cl_allocate - allocates cl  structure and sets it up.
+ *
+ * @dev: mei device
+ * Return:  The allocated file or NULL on failure
+ */
+struct mei_cl *mei_cl_allocate(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
+	if (!cl)
+		return NULL;
+
+	mei_cl_init(cl, dev);
+
+	return cl;
+}
+
+/**
+ * mei_cl_link - allocate host id in the host map
+ *
+ * @cl: host client
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
+ *
+ * Return: 0 on success
+ *	-EINVAL on incorrect values
+ *	-EMFILE if open count exceeded.
+ */
+int mei_cl_link(struct mei_cl *cl, int id)
+{
+	struct mei_device *dev;
+	long open_handle_count;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	/* If Id is not assigned get one*/
+	if (id == MEI_HOST_CLIENT_ID_ANY)
+		id = find_first_zero_bit(dev->host_clients_map,
+					MEI_CLIENTS_MAX);
+
+	if (id >= MEI_CLIENTS_MAX) {
+		dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
+		return -EMFILE;
+	}
+
+	open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
+	if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
+		dev_err(dev->dev, "open_handle_count exceeded %d",
+			MEI_MAX_OPEN_HANDLE_COUNT);
+		return -EMFILE;
+	}
+
+	dev->open_handle_count++;
+
+	cl->host_client_id = id;
+	list_add_tail(&cl->link, &dev->file_list);
+
+	set_bit(id, dev->host_clients_map);
+
+	cl->state = MEI_FILE_INITIALIZING;
+
+	cl_dbg(dev, cl, "link cl\n");
+	return 0;
+}
+
+/**
+ * mei_cl_unlink - remove me_cl from the list
+ *
+ * @cl: host client
+ *
+ * Return: always 0
+ */
+int mei_cl_unlink(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+
+	/* don't shout on error exit path */
+	if (!cl)
+		return 0;
+
+	/* wd and amthif might not be initialized */
+	if (!cl->dev)
+		return 0;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "unlink client");
+
+	if (dev->open_handle_count > 0)
+		dev->open_handle_count--;
+
+	/* never clear the 0 bit */
+	if (cl->host_client_id)
+		clear_bit(cl->host_client_id, dev->host_clients_map);
+
+	list_del_init(&cl->link);
+
+	cl->state = MEI_FILE_INITIALIZING;
+
+	return 0;
+}
+
+
+void mei_host_client_init(struct work_struct *work)
+{
+	struct mei_device *dev =
+		container_of(work, struct mei_device, init_work);
+	struct mei_me_client *me_cl;
+
+	mutex_lock(&dev->device_lock);
+
+
+	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);
+	dev_dbg(dev->dev, "rpm: autosuspend\n");
+	pm_runtime_autosuspend(dev->dev);
+}
+
+/**
+ * mei_hbuf_acquire - try to acquire host buffer
+ *
+ * @dev: the device structure
+ * Return: true if host buffer was acquired
+ */
+bool mei_hbuf_acquire(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) == MEI_PG_ON ||
+	    mei_pg_in_transition(dev)) {
+		dev_dbg(dev->dev, "device is in pg\n");
+		return false;
+	}
+
+	if (!dev->hbuf_is_ready) {
+		dev_dbg(dev->dev, "hbuf is not ready\n");
+		return false;
+	}
+
+	dev->hbuf_is_ready = false;
+
+	return true;
+}
+
+/**
+ * mei_cl_disconnect - disconnect host client from the me one
+ *
+ * @cl: host client
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_disconnect(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	cl_dbg(dev, cl, "disconnecting");
+
+	if (cl->state != MEI_FILE_DISCONNECTING)
+		return 0;
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT, NULL);
+	rets = cb ? 0 : -ENOMEM;
+	if (rets)
+		goto free;
+
+	if (mei_hbuf_acquire(dev)) {
+		if (mei_hbm_cl_disconnect_req(dev, cl)) {
+			rets = -ENODEV;
+			cl_err(dev, cl, "failed to disconnect.\n");
+			goto free;
+		}
+		cl->timer_count = MEI_CONNECT_TIMEOUT;
+		mdelay(10); /* Wait for hardware disconnection ready */
+		list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
+	} else {
+		cl_dbg(dev, cl, "add disconnect cb to control write list\n");
+		list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
+
+	}
+	mutex_unlock(&dev->device_lock);
+
+	wait_event_timeout(cl->wait,
+			MEI_FILE_DISCONNECTED == cl->state,
+			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+
+	mutex_lock(&dev->device_lock);
+
+	if (MEI_FILE_DISCONNECTED == cl->state) {
+		rets = 0;
+		cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
+	} else {
+		cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
+		rets = -ETIME;
+	}
+
+	mei_io_list_flush(&dev->ctrl_rd_list, cl);
+	mei_io_list_flush(&dev->ctrl_wr_list, cl);
+free:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	mei_io_cb_free(cb);
+	return rets;
+}
+
+
+/**
+ * mei_cl_is_other_connecting - checks if other
+ *    client with the same me client id is connecting
+ *
+ * @cl: private data of the file object
+ *
+ * Return: true if other client is connected, false - otherwise.
+ */
+bool mei_cl_is_other_connecting(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_cl *ocl; /* the other client */
+
+	if (WARN_ON(!cl || !cl->dev))
+		return false;
+
+	dev = cl->dev;
+
+	list_for_each_entry(ocl, &dev->file_list, link) {
+		if (ocl->state == MEI_FILE_CONNECTING &&
+		    ocl != cl &&
+		    cl->me_client_id == ocl->me_client_id)
+			return true;
+
+	}
+
+	return false;
+}
+
+/**
+ * mei_cl_connect - connect host client to the me one
+ *
+ * @cl: host client
+ * @file: pointer to file structure
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_connect(struct mei_cl *cl, struct file *file)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	cb = mei_io_cb_init(cl, MEI_FOP_CONNECT, file);
+	rets = cb ? 0 : -ENOMEM;
+	if (rets)
+		goto out;
+
+	/* run hbuf acquire last so we don't have to undo */
+	if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
+		cl->state = MEI_FILE_CONNECTING;
+		if (mei_hbm_cl_connect_req(dev, cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+		cl->timer_count = MEI_CONNECT_TIMEOUT;
+		list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
+	} else {
+		cl->state = MEI_FILE_INITIALIZING;
+		list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
+	}
+
+	mutex_unlock(&dev->device_lock);
+	wait_event_timeout(cl->wait,
+			(cl->state == MEI_FILE_CONNECTED ||
+			 cl->state == MEI_FILE_DISCONNECTED),
+			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	if (!mei_cl_is_connected(cl)) {
+		cl->state = MEI_FILE_DISCONNECTED;
+		/* something went really wrong */
+		if (!cl->status)
+			cl->status = -EFAULT;
+
+		mei_io_list_flush(&dev->ctrl_rd_list, cl);
+		mei_io_list_flush(&dev->ctrl_wr_list, cl);
+	}
+
+	rets = cl->status;
+
+out:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	mei_io_cb_free(cb);
+	return rets;
+}
+
+/**
+ * mei_cl_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
+ *
+ * Return: 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
+ *	-ENOENT if mei_cl is not present
+ *	-EINVAL if single_recv_buf == 0
+ */
+int mei_cl_flow_ctrl_creds(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_me_client *me_cl;
+	int rets = 0;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	if (cl->mei_flow_ctrl_creds > 0)
+		return 1;
+
+	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);
+		return -ENOENT;
+	}
+
+	if (me_cl->mei_flow_ctrl_creds > 0) {
+		rets = 1;
+		if (WARN_ON(me_cl->props.single_recv_buf == 0))
+			rets = -EINVAL;
+	}
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_cl_flow_ctrl_reduce - reduces flow_control.
+ *
+ * @cl: private data of the file object
+ *
+ * Return:
+ *	0 on success
+ *	-ENOENT when me client is not found
+ *	-EINVAL when ctrl credits are <= 0
+ */
+int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
+{
+	struct mei_device *dev;
+	struct mei_me_client *me_cl;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+	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);
+		return -ENOENT;
+	}
+
+	if (me_cl->props.single_recv_buf) {
+		if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0)) {
+			rets = -EINVAL;
+			goto out;
+		}
+		me_cl->mei_flow_ctrl_creds--;
+	} else {
+		if (WARN_ON(cl->mei_flow_ctrl_creds <= 0)) {
+			rets = -EINVAL;
+			goto out;
+		}
+		cl->mei_flow_ctrl_creds--;
+	}
+	rets = 0;
+out:
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_cl_read_start - the start read client message function.
+ *
+ * @cl: host client
+ * @length: number of bytes to read
+ * @fp: pointer to file structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_cl_read_start(struct mei_cl *cl, size_t length, struct file *fp)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	struct mei_me_client *me_cl;
+	int rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	if (!mei_cl_is_connected(cl))
+		return -ENODEV;
+
+	/* 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);
+		return  -ENOTTY;
+	}
+	/* always allocate at least client max message */
+	length = max_t(size_t, length, me_cl->props.max_msg_length);
+	mei_me_cl_put(me_cl);
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_READ, fp);
+	rets = cb ? 0 : -ENOMEM;
+	if (rets)
+		goto out;
+
+	if (mei_hbuf_acquire(dev)) {
+		rets = mei_hbm_cl_flow_control_req(dev, cl);
+		if (rets < 0)
+			goto out;
+
+		list_add_tail(&cb->list, &cl->rd_pending);
+	} else {
+		list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
+	}
+
+out:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	if (rets)
+		mei_io_cb_free(cb);
+
+	return rets;
+}
+
+/**
+ * mei_cl_irq_write - write a message to device
+ *	from the interrupt thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise error.
+ */
+int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
+		     struct 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;
+
+	dev = cl->dev;
+
+	buf = &cb->buf;
+
+	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;
+	}
+
+	slots = mei_hbuf_empty_slots(dev);
+	len = buf->size - cb->buf_idx;
+	msg_slots = mei_data2slots(len);
+
+	mei_hdr.host_addr = cl->host_client_id;
+	mei_hdr.me_addr = cl->me_client_id;
+	mei_hdr.reserved = 0;
+	mei_hdr.internal = cb->internal;
+
+	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;
+	}
+
+	cl_dbg(dev, cl, "buf: size = %d idx = %lu\n",
+			cb->buf.size, cb->buf_idx);
+
+	rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
+	if (rets) {
+		cl->status = rets;
+		list_move_tail(&cb->list, &cmpl_list->list);
+		return rets;
+	}
+
+	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))
+			return -EIO;
+		list_move_tail(&cb->list, &dev->write_waiting_list.list);
+	}
+
+	return 0;
+}
+
+/**
+ * mei_cl_write - submit a write cb to mei device
+ *	assumes device_lock is locked
+ *
+ * @cl: host client
+ * @cb: write callback with filled data
+ * @blocking: block until completed
+ *
+ * Return: number of bytes sent on success, <0 on failure.
+ */
+int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
+{
+	struct mei_device *dev;
+	struct mei_msg_data *buf;
+	struct mei_msg_hdr mei_hdr;
+	int rets;
+
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	if (WARN_ON(!cb))
+		return -EINVAL;
+
+	dev = cl->dev;
+
+
+	buf = &cb->buf;
+
+	cl_dbg(dev, cl, "size=%d\n", buf->size);
+
+	rets = pm_runtime_get(dev->dev);
+	if (rets < 0 && rets != -EINPROGRESS) {
+		pm_runtime_put_noidle(dev->dev);
+		cl_err(dev, cl, "rpm: get failed %d\n", rets);
+		return rets;
+	}
+
+	cb->buf_idx = 0;
+	cl->writing_state = MEI_IDLE;
+
+	mei_hdr.host_addr = cl->host_client_id;
+	mei_hdr.me_addr = cl->me_client_id;
+	mei_hdr.reserved = 0;
+	mei_hdr.msg_complete = 0;
+	mei_hdr.internal = cb->internal;
+
+	rets = mei_cl_flow_ctrl_creds(cl);
+	if (rets < 0)
+		goto err;
+
+	if (rets == 0) {
+		cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
+		rets = buf->size;
+		goto out;
+	}
+	if (!mei_hbuf_acquire(dev)) {
+		cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
+		rets = buf->size;
+		goto out;
+	}
+
+	/* Check for a maximum length */
+	if (buf->size > mei_hbuf_max_len(dev)) {
+		mei_hdr.length = mei_hbuf_max_len(dev);
+		mei_hdr.msg_complete = 0;
+	} else {
+		mei_hdr.length = buf->size;
+		mei_hdr.msg_complete = 1;
+	}
+
+	rets = mei_write_message(dev, &mei_hdr, buf->data);
+	if (rets)
+		goto err;
+
+	cl->writing_state = MEI_WRITING;
+	cb->buf_idx = mei_hdr.length;
+	cb->completed = mei_hdr.msg_complete == 1;
+
+out:
+	if (mei_hdr.msg_complete) {
+		rets = mei_cl_flow_ctrl_reduce(cl);
+		if (rets < 0)
+			goto err;
+
+		list_add_tail(&cb->list, &dev->write_waiting_list.list);
+	} else {
+		list_add_tail(&cb->list, &dev->write_list.list);
+	}
+
+
+	if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
+
+		mutex_unlock(&dev->device_lock);
+		rets = wait_event_interruptible(cl->tx_wait,
+				cl->writing_state == MEI_WRITE_COMPLETE);
+		mutex_lock(&dev->device_lock);
+		/* wait_event_interruptible returns -ERESTARTSYS */
+		if (rets) {
+			if (signal_pending(current))
+				rets = -EINTR;
+			goto err;
+		}
+	}
+
+	rets = buf->size;
+err:
+	cl_dbg(dev, cl, "rpm: autosuspend\n");
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
+
+	return rets;
+}
+
+
+/**
+ * mei_cl_complete - processes completed operation for a client
+ *
+ * @cl: private data of the file object.
+ * @cb: callback block.
+ */
+void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+	if (cb->fop_type == MEI_FOP_WRITE) {
+		mei_io_cb_free(cb);
+		cb = NULL;
+		cl->writing_state = MEI_WRITE_COMPLETE;
+		if (waitqueue_active(&cl->tx_wait))
+			wake_up_interruptible(&cl->tx_wait);
+
+	} 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_all(&cl->rx_wait);
+		else
+			mei_cl_bus_rx_event(cl);
+
+	}
+}
+
+
+/**
+ * mei_cl_all_disconnect - disconnect forcefully all connected clients
+ *
+ * @dev: mei device
+ */
+
+void mei_cl_all_disconnect(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->file_list, link) {
+		cl->state = MEI_FILE_DISCONNECTED;
+		cl->mei_flow_ctrl_creds = 0;
+		cl->timer_count = 0;
+	}
+}
+
+
+/**
+ * mei_cl_all_wakeup  - wake up all readers and writers they can be interrupted
+ *
+ * @dev: mei device
+ */
+void mei_cl_all_wakeup(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->file_list, link) {
+		if (waitqueue_active(&cl->rx_wait)) {
+			cl_dbg(dev, cl, "Waking up reading client!\n");
+			wake_up_interruptible(&cl->rx_wait);
+		}
+		if (waitqueue_active(&cl->tx_wait)) {
+			cl_dbg(dev, cl, "Waking up writing client!\n");
+			wake_up_interruptible(&cl->tx_wait);
+		}
+	}
+}
+
+/**
+ * mei_cl_all_write_clear - clear all pending writes
+ *
+ * @dev: mei device
+ */
+void mei_cl_all_write_clear(struct mei_device *dev)
+{
+	mei_io_list_free(&dev->write_list, NULL);
+	mei_io_list_free(&dev->write_waiting_list, NULL);
+}
+
+