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-rw-r--r--drivers/misc/mei/client.c2435
1 files changed, 2435 insertions, 0 deletions
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
new file mode 100644
index 000000000..c70c89209
--- /dev/null
+++ b/drivers/misc/mei/client.c
@@ -0,0 +1,2435 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2022, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/sched/signal.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/dma-mapping.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 from 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_init(&me_cl->list);
+ mei_me_cl_put(me_cl);
+}
+
+/**
+ * mei_me_cl_del - delete me client from the list and decrease
+ * reference counter
+ *
+ * @dev: mei device
+ * @me_cl: me client
+ */
+void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
+{
+ down_write(&dev->me_clients_rwsem);
+ __mei_me_cl_del(dev, me_cl);
+ up_write(&dev->me_clients_rwsem);
+}
+
+/**
+ * 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);
+ mei_me_cl_put(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);
+ mei_me_cl_put(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_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_tx_cb_enqueue - queue tx callback
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cb: mei callback struct
+ * @head: an instance of list to queue on
+ */
+static inline void mei_tx_cb_enqueue(struct mei_cl_cb *cb,
+ struct list_head *head)
+{
+ list_add_tail(&cb->list, head);
+ cb->cl->tx_cb_queued++;
+}
+
+/**
+ * mei_tx_cb_dequeue - dequeue tx callback
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cb: mei callback struct to dequeue and free
+ */
+static inline void mei_tx_cb_dequeue(struct mei_cl_cb *cb)
+{
+ if (!WARN_ON(cb->cl->tx_cb_queued == 0))
+ cb->cl->tx_cb_queued--;
+
+ mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_set_read_by_fp - set pending_read flag to vtag struct for given fp
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * @cl: mei client
+ * @fp: pointer to file structure
+ */
+static void mei_cl_set_read_by_fp(const struct mei_cl *cl,
+ const struct file *fp)
+{
+ struct mei_cl_vtag *cl_vtag;
+
+ list_for_each_entry(cl_vtag, &cl->vtag_map, list) {
+ if (cl_vtag->fp == fp) {
+ cl_vtag->pending_read = true;
+ return;
+ }
+ }
+}
+
+/**
+ * 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;
+ */
+static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
+ enum mei_cb_file_ops type,
+ const struct file *fp)
+{
+ struct mei_cl_cb *cb;
+
+ cb = kzalloc(sizeof(*cb), GFP_KERNEL);
+ if (!cb)
+ return NULL;
+
+ INIT_LIST_HEAD(&cb->list);
+ cb->fp = fp;
+ cb->cl = cl;
+ cb->buf_idx = 0;
+ cb->fop_type = type;
+ cb->vtag = 0;
+
+ return cb;
+}
+
+/**
+ * mei_io_list_flush_cl - removes cbs belonging to the cl.
+ *
+ * @head: an instance of our list structure
+ * @cl: host client
+ */
+static void mei_io_list_flush_cl(struct list_head *head,
+ const struct mei_cl *cl)
+{
+ struct mei_cl_cb *cb, *next;
+
+ list_for_each_entry_safe(cb, next, head, list) {
+ if (cl == cb->cl) {
+ list_del_init(&cb->list);
+ if (cb->fop_type == MEI_FOP_READ)
+ mei_io_cb_free(cb);
+ }
+ }
+}
+
+/**
+ * mei_io_tx_list_free_cl - removes cb belonging to the cl and free them
+ *
+ * @head: An instance of our list structure
+ * @cl: host client
+ * @fp: file pointer (matching cb file object), may be NULL
+ */
+static void mei_io_tx_list_free_cl(struct list_head *head,
+ const struct mei_cl *cl,
+ const struct file *fp)
+{
+ struct mei_cl_cb *cb, *next;
+
+ list_for_each_entry_safe(cb, next, head, list) {
+ if (cl == cb->cl && (!fp || fp == cb->fp))
+ mei_tx_cb_dequeue(cb);
+ }
+}
+
+/**
+ * mei_io_list_free_fp - free cb from a list that matches file pointer
+ *
+ * @head: io list
+ * @fp: file pointer (matching cb file object), may be NULL
+ */
+static void mei_io_list_free_fp(struct list_head *head, const struct file *fp)
+{
+ struct mei_cl_cb *cb, *next;
+
+ list_for_each_entry_safe(cb, next, head, list)
+ if (!fp || fp == cb->fp)
+ mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_free_pending - free pending cb
+ *
+ * @cl: host client
+ */
+static void mei_cl_free_pending(struct mei_cl *cl)
+{
+ struct mei_cl_cb *cb;
+
+ cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
+ mei_io_cb_free(cb);
+}
+
+/**
+ * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
+ *
+ * @cl: host client
+ * @length: size of the buffer
+ * @fop_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 fop_type,
+ const struct file *fp)
+{
+ struct mei_cl_cb *cb;
+
+ cb = mei_io_cb_init(cl, fop_type, fp);
+ if (!cb)
+ return NULL;
+
+ if (length == 0)
+ return cb;
+
+ cb->buf.data = kmalloc(roundup(length, MEI_SLOT_SIZE), GFP_KERNEL);
+ if (!cb->buf.data) {
+ mei_io_cb_free(cb);
+ return NULL;
+ }
+ cb->buf.size = length;
+
+ return cb;
+}
+
+/**
+ * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
+ * and enqueuing of the control commands cb
+ *
+ * @cl: host client
+ * @length: size of the buffer
+ * @fop_type: operation type
+ * @fp: associated file pointer (might be NULL)
+ *
+ * Return: cb on success and NULL on failure
+ * Locking: called under "dev->device_lock" lock
+ */
+struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
+ enum mei_cb_file_ops fop_type,
+ const struct file *fp)
+{
+ struct mei_cl_cb *cb;
+
+ /* for RX always allocate at least client's mtu */
+ if (length)
+ length = max_t(size_t, length, mei_cl_mtu(cl));
+
+ cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
+ if (!cb)
+ return NULL;
+
+ list_add_tail(&cb->list, &cl->dev->ctrl_wr_list);
+ 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(struct mei_cl *cl, const struct file *fp)
+{
+ struct mei_cl_cb *cb;
+ struct mei_cl_cb *ret_cb = NULL;
+
+ spin_lock(&cl->rd_completed_lock);
+ list_for_each_entry(cb, &cl->rd_completed, list)
+ if (!fp || fp == cb->fp) {
+ ret_cb = cb;
+ break;
+ }
+ spin_unlock(&cl->rd_completed_lock);
+ return ret_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_tx_list_free_cl(&cl->dev->write_list, cl, fp);
+ mei_io_tx_list_free_cl(&cl->dev->write_waiting_list, cl, fp);
+ /* free pending and control cb only in final flush */
+ if (!fp) {
+ mei_io_list_flush_cl(&cl->dev->ctrl_wr_list, cl);
+ mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl);
+ mei_cl_free_pending(cl);
+ }
+ spin_lock(&cl->rd_completed_lock);
+ mei_io_list_free_fp(&cl->rd_completed, fp);
+ spin_unlock(&cl->rd_completed_lock);
+
+ return 0;
+}
+
+/**
+ * mei_cl_init - initializes cl.
+ *
+ * @cl: host client to be initialized
+ * @dev: mei device
+ */
+static void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
+{
+ memset(cl, 0, sizeof(*cl));
+ init_waitqueue_head(&cl->wait);
+ init_waitqueue_head(&cl->rx_wait);
+ init_waitqueue_head(&cl->tx_wait);
+ init_waitqueue_head(&cl->ev_wait);
+ INIT_LIST_HEAD(&cl->vtag_map);
+ spin_lock_init(&cl->rd_completed_lock);
+ INIT_LIST_HEAD(&cl->rd_completed);
+ INIT_LIST_HEAD(&cl->rd_pending);
+ INIT_LIST_HEAD(&cl->link);
+ cl->writing_state = MEI_IDLE;
+ cl->state = MEI_FILE_UNINITIALIZED;
+ 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(*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
+ *
+ * Return: 0 on success
+ * -EINVAL on incorrect values
+ * -EMFILE if open count exceeded.
+ */
+int mei_cl_link(struct mei_cl *cl)
+{
+ struct mei_device *dev;
+ int id;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -EINVAL;
+
+ dev = cl->dev;
+
+ 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;
+ }
+
+ if (dev->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 host client 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;
+
+ if (WARN_ON(!cl->dev))
+ return 0;
+
+ dev = cl->dev;
+
+ cl_dbg(dev, cl, "unlink client");
+
+ if (cl->state == MEI_FILE_UNINITIALIZED)
+ return 0;
+
+ 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_UNINITIALIZED;
+ cl->writing_state = MEI_IDLE;
+
+ WARN_ON(!list_empty(&cl->rd_completed) ||
+ !list_empty(&cl->rd_pending) ||
+ !list_empty(&cl->link));
+
+ return 0;
+}
+
+void mei_host_client_init(struct mei_device *dev)
+{
+ mei_set_devstate(dev, MEI_DEV_ENABLED);
+ dev->reset_count = 0;
+
+ schedule_work(&dev->bus_rescan_work);
+
+ pm_runtime_mark_last_busy(dev->dev);
+ dev_dbg(dev->dev, "rpm: autosuspend\n");
+ pm_request_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_wake_all - wake up readers, writers and event waiters so
+ * they can be interrupted
+ *
+ * @cl: host client
+ */
+static void mei_cl_wake_all(struct mei_cl *cl)
+{
+ struct mei_device *dev = cl->dev;
+
+ /* synchronized under device mutex */
+ if (waitqueue_active(&cl->rx_wait)) {
+ cl_dbg(dev, cl, "Waking up reading client!\n");
+ wake_up_interruptible(&cl->rx_wait);
+ }
+ /* synchronized under device mutex */
+ if (waitqueue_active(&cl->tx_wait)) {
+ cl_dbg(dev, cl, "Waking up writing client!\n");
+ wake_up_interruptible(&cl->tx_wait);
+ }
+ /* synchronized under device mutex */
+ if (waitqueue_active(&cl->ev_wait)) {
+ cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
+ wake_up_interruptible(&cl->ev_wait);
+ }
+ /* synchronized under device mutex */
+ if (waitqueue_active(&cl->wait)) {
+ cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
+ wake_up(&cl->wait);
+ }
+}
+
+/**
+ * mei_cl_set_disconnected - set disconnected state and clear
+ * associated states and resources
+ *
+ * @cl: host client
+ */
+static void mei_cl_set_disconnected(struct mei_cl *cl)
+{
+ struct mei_device *dev = cl->dev;
+
+ if (cl->state == MEI_FILE_DISCONNECTED ||
+ cl->state <= MEI_FILE_INITIALIZING)
+ return;
+
+ cl->state = MEI_FILE_DISCONNECTED;
+ mei_io_tx_list_free_cl(&dev->write_list, cl, NULL);
+ mei_io_tx_list_free_cl(&dev->write_waiting_list, cl, NULL);
+ mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
+ mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
+ mei_cl_wake_all(cl);
+ cl->rx_flow_ctrl_creds = 0;
+ cl->tx_flow_ctrl_creds = 0;
+ cl->timer_count = 0;
+
+ if (!cl->me_cl)
+ return;
+
+ if (!WARN_ON(cl->me_cl->connect_count == 0))
+ cl->me_cl->connect_count--;
+
+ if (cl->me_cl->connect_count == 0)
+ cl->me_cl->tx_flow_ctrl_creds = 0;
+
+ mei_me_cl_put(cl->me_cl);
+ cl->me_cl = NULL;
+}
+
+static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
+{
+ if (!mei_me_cl_get(me_cl))
+ return -ENOENT;
+
+ /* only one connection is allowed for fixed address clients */
+ if (me_cl->props.fixed_address) {
+ if (me_cl->connect_count) {
+ mei_me_cl_put(me_cl);
+ return -EBUSY;
+ }
+ }
+
+ cl->me_cl = me_cl;
+ cl->state = MEI_FILE_CONNECTING;
+ cl->me_cl->connect_count++;
+
+ return 0;
+}
+
+/*
+ * mei_cl_send_disconnect - send disconnect request
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+ struct mei_device *dev;
+ int ret;
+
+ dev = cl->dev;
+
+ ret = mei_hbm_cl_disconnect_req(dev, cl);
+ cl->status = ret;
+ if (ret) {
+ cl->state = MEI_FILE_DISCONNECT_REPLY;
+ return ret;
+ }
+
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ cl->timer_count = dev->timeouts.connect;
+ mei_schedule_stall_timer(dev);
+
+ return 0;
+}
+
+/**
+ * mei_cl_irq_disconnect - processes close related operation from
+ * interrupt thread context - send disconnect request
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
+ struct list_head *cmpl_list)
+{
+ struct mei_device *dev = cl->dev;
+ u32 msg_slots;
+ int slots;
+ int ret;
+
+ msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+ slots = mei_hbuf_empty_slots(dev);
+ if (slots < 0)
+ return -EOVERFLOW;
+
+ if ((u32)slots < msg_slots)
+ return -EMSGSIZE;
+
+ ret = mei_cl_send_disconnect(cl, cb);
+ if (ret)
+ list_move_tail(&cb->list, cmpl_list);
+
+ return ret;
+}
+
+/**
+ * __mei_cl_disconnect - disconnect host client from the me one
+ * internal function runtime pm has to be already acquired
+ *
+ * @cl: host client
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int __mei_cl_disconnect(struct mei_cl *cl)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ int rets;
+
+ dev = cl->dev;
+
+ cl->state = MEI_FILE_DISCONNECTING;
+
+ cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ if (mei_hbuf_acquire(dev)) {
+ rets = mei_cl_send_disconnect(cl, cb);
+ if (rets) {
+ cl_err(dev, cl, "failed to disconnect.\n");
+ goto out;
+ }
+ }
+
+ mutex_unlock(&dev->device_lock);
+ wait_event_timeout(cl->wait,
+ cl->state == MEI_FILE_DISCONNECT_REPLY ||
+ cl->state == MEI_FILE_DISCONNECTED,
+ dev->timeouts.cl_connect);
+ mutex_lock(&dev->device_lock);
+
+ rets = cl->status;
+ if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
+ cl->state != MEI_FILE_DISCONNECTED) {
+ cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
+ rets = -ETIME;
+ }
+
+out:
+ /* we disconnect also on error */
+ mei_cl_set_disconnected(cl);
+ if (!rets)
+ cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
+
+ mei_io_cb_free(cb);
+ return rets;
+}
+
+/**
+ * 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;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ cl_dbg(dev, cl, "disconnecting");
+
+ if (!mei_cl_is_connected(cl))
+ return 0;
+
+ if (mei_cl_is_fixed_address(cl)) {
+ mei_cl_set_disconnected(cl);
+ return 0;
+ }
+
+ if (dev->dev_state == MEI_DEV_POWERING_DOWN ||
+ dev->dev_state == MEI_DEV_POWER_DOWN) {
+ cl_dbg(dev, cl, "Device is powering down, don't bother with disconnection\n");
+ mei_cl_set_disconnected(cl);
+ 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;
+ }
+
+ rets = __mei_cl_disconnect(cl);
+
+ cl_dbg(dev, cl, "rpm: autosuspend\n");
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
+ 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.
+ */
+static bool mei_cl_is_other_connecting(struct mei_cl *cl)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+
+ dev = cl->dev;
+
+ list_for_each_entry(cb, &dev->ctrl_rd_list, list) {
+ if (cb->fop_type == MEI_FOP_CONNECT &&
+ mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * mei_cl_send_connect - send connect request
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+ struct mei_device *dev;
+ int ret;
+
+ dev = cl->dev;
+
+ ret = mei_hbm_cl_connect_req(dev, cl);
+ cl->status = ret;
+ if (ret) {
+ cl->state = MEI_FILE_DISCONNECT_REPLY;
+ return ret;
+ }
+
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ cl->timer_count = dev->timeouts.connect;
+ mei_schedule_stall_timer(dev);
+ return 0;
+}
+
+/**
+ * mei_cl_irq_connect - send connect request in irq_thread context
+ *
+ * @cl: host client
+ * @cb: callback block
+ * @cmpl_list: complete list
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
+ struct list_head *cmpl_list)
+{
+ struct mei_device *dev = cl->dev;
+ u32 msg_slots;
+ int slots;
+ int rets;
+
+ if (mei_cl_is_other_connecting(cl))
+ return 0;
+
+ msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+ slots = mei_hbuf_empty_slots(dev);
+ if (slots < 0)
+ return -EOVERFLOW;
+
+ if ((u32)slots < msg_slots)
+ return -EMSGSIZE;
+
+ rets = mei_cl_send_connect(cl, cb);
+ if (rets)
+ list_move_tail(&cb->list, cmpl_list);
+
+ return rets;
+}
+
+/**
+ * mei_cl_connect - connect host client to the me one
+ *
+ * @cl: host client
+ * @me_cl: me client
+ * @fp: 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 mei_me_client *me_cl,
+ const struct file *fp)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev || !me_cl))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ rets = mei_cl_set_connecting(cl, me_cl);
+ if (rets)
+ goto nortpm;
+
+ if (mei_cl_is_fixed_address(cl)) {
+ cl->state = MEI_FILE_CONNECTED;
+ rets = 0;
+ goto nortpm;
+ }
+
+ 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);
+ goto nortpm;
+ }
+
+ cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ /* run hbuf acquire last so we don't have to undo */
+ if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
+ rets = mei_cl_send_connect(cl, cb);
+ if (rets)
+ goto out;
+ }
+
+ mutex_unlock(&dev->device_lock);
+ wait_event_timeout(cl->wait,
+ (cl->state == MEI_FILE_CONNECTED ||
+ cl->state == MEI_FILE_DISCONNECTED ||
+ cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
+ cl->state == MEI_FILE_DISCONNECT_REPLY),
+ dev->timeouts.cl_connect);
+ mutex_lock(&dev->device_lock);
+
+ if (!mei_cl_is_connected(cl)) {
+ if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
+ mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
+ mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
+ /* ignore disconnect return valuue;
+ * in case of failure reset will be invoked
+ */
+ __mei_cl_disconnect(cl);
+ rets = -EFAULT;
+ goto out;
+ }
+
+ /* timeout or something went really wrong */
+ if (!cl->status)
+ cl->status = -EFAULT;
+ }
+
+ 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);
+
+nortpm:
+ if (!mei_cl_is_connected(cl))
+ mei_cl_set_disconnected(cl);
+
+ return rets;
+}
+
+/**
+ * mei_cl_alloc_linked - allocate and link host client
+ *
+ * @dev: the device structure
+ *
+ * Return: cl on success ERR_PTR on failure
+ */
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
+{
+ struct mei_cl *cl;
+ int ret;
+
+ cl = mei_cl_allocate(dev);
+ if (!cl) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = mei_cl_link(cl);
+ if (ret)
+ goto err;
+
+ return cl;
+err:
+ kfree(cl);
+ return ERR_PTR(ret);
+}
+
+/**
+ * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
+ *
+ * @cl: host client
+ *
+ * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
+ */
+static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
+{
+ if (WARN_ON(!cl || !cl->me_cl))
+ return -EINVAL;
+
+ if (cl->tx_flow_ctrl_creds > 0)
+ return 1;
+
+ if (mei_cl_is_fixed_address(cl))
+ return 1;
+
+ if (mei_cl_is_single_recv_buf(cl)) {
+ if (cl->me_cl->tx_flow_ctrl_creds > 0)
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
+ * for a client
+ *
+ * @cl: host client
+ *
+ * Return:
+ * 0 on success
+ * -EINVAL when ctrl credits are <= 0
+ */
+static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
+{
+ if (WARN_ON(!cl || !cl->me_cl))
+ return -EINVAL;
+
+ if (mei_cl_is_fixed_address(cl))
+ return 0;
+
+ if (mei_cl_is_single_recv_buf(cl)) {
+ if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
+ return -EINVAL;
+ cl->me_cl->tx_flow_ctrl_creds--;
+ } else {
+ if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
+ return -EINVAL;
+ cl->tx_flow_ctrl_creds--;
+ }
+ return 0;
+}
+
+/**
+ * mei_cl_vtag_alloc - allocate and fill the vtag structure
+ *
+ * @fp: pointer to file structure
+ * @vtag: vm tag
+ *
+ * Return:
+ * * Pointer to allocated struct - on success
+ * * ERR_PTR(-ENOMEM) on memory allocation failure
+ */
+struct mei_cl_vtag *mei_cl_vtag_alloc(struct file *fp, u8 vtag)
+{
+ struct mei_cl_vtag *cl_vtag;
+
+ cl_vtag = kzalloc(sizeof(*cl_vtag), GFP_KERNEL);
+ if (!cl_vtag)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&cl_vtag->list);
+ cl_vtag->vtag = vtag;
+ cl_vtag->fp = fp;
+
+ return cl_vtag;
+}
+
+/**
+ * mei_cl_fp_by_vtag - obtain the file pointer by vtag
+ *
+ * @cl: host client
+ * @vtag: virtual tag
+ *
+ * Return:
+ * * A file pointer - on success
+ * * ERR_PTR(-ENOENT) if vtag is not found in the client vtag list
+ */
+const struct file *mei_cl_fp_by_vtag(const struct mei_cl *cl, u8 vtag)
+{
+ struct mei_cl_vtag *vtag_l;
+
+ list_for_each_entry(vtag_l, &cl->vtag_map, list)
+ /* The client on bus has one fixed fp */
+ if ((cl->cldev && mei_cldev_enabled(cl->cldev)) ||
+ vtag_l->vtag == vtag)
+ return vtag_l->fp;
+
+ return ERR_PTR(-ENOENT);
+}
+
+/**
+ * mei_cl_reset_read_by_vtag - reset pending_read flag by given vtag
+ *
+ * @cl: host client
+ * @vtag: vm tag
+ */
+static void mei_cl_reset_read_by_vtag(const struct mei_cl *cl, u8 vtag)
+{
+ struct mei_cl_vtag *vtag_l;
+
+ list_for_each_entry(vtag_l, &cl->vtag_map, list) {
+ if (vtag_l->vtag == vtag) {
+ vtag_l->pending_read = false;
+ break;
+ }
+ }
+}
+
+/**
+ * mei_cl_read_vtag_add_fc - add flow control for next pending reader
+ * in the vtag list
+ *
+ * @cl: host client
+ */
+static void mei_cl_read_vtag_add_fc(struct mei_cl *cl)
+{
+ struct mei_cl_vtag *cl_vtag;
+
+ list_for_each_entry(cl_vtag, &cl->vtag_map, list) {
+ if (cl_vtag->pending_read) {
+ if (mei_cl_enqueue_ctrl_wr_cb(cl,
+ mei_cl_mtu(cl),
+ MEI_FOP_READ,
+ cl_vtag->fp))
+ cl->rx_flow_ctrl_creds++;
+ break;
+ }
+ }
+}
+
+/**
+ * mei_cl_vt_support_check - check if client support vtags
+ *
+ * @cl: host client
+ *
+ * Return:
+ * * 0 - supported, or not connected at all
+ * * -EOPNOTSUPP - vtags are not supported by client
+ */
+int mei_cl_vt_support_check(const struct mei_cl *cl)
+{
+ struct mei_device *dev = cl->dev;
+
+ if (!dev->hbm_f_vt_supported)
+ return -EOPNOTSUPP;
+
+ if (!cl->me_cl)
+ return 0;
+
+ return cl->me_cl->props.vt_supported ? 0 : -EOPNOTSUPP;
+}
+
+/**
+ * mei_cl_add_rd_completed - add read completed callback to list with lock
+ * and vtag check
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ */
+void mei_cl_add_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+ const struct file *fp;
+
+ if (!mei_cl_vt_support_check(cl)) {
+ fp = mei_cl_fp_by_vtag(cl, cb->vtag);
+ if (IS_ERR(fp)) {
+ /* client already disconnected, discarding */
+ mei_io_cb_free(cb);
+ return;
+ }
+ cb->fp = fp;
+ mei_cl_reset_read_by_vtag(cl, cb->vtag);
+ mei_cl_read_vtag_add_fc(cl);
+ }
+
+ spin_lock(&cl->rd_completed_lock);
+ list_add_tail(&cb->list, &cl->rd_completed);
+ spin_unlock(&cl->rd_completed_lock);
+}
+
+/**
+ * mei_cl_del_rd_completed - free read completed callback with lock
+ *
+ * @cl: host client
+ * @cb: callback block
+ *
+ */
+void mei_cl_del_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+ spin_lock(&cl->rd_completed_lock);
+ mei_io_cb_free(cb);
+ spin_unlock(&cl->rd_completed_lock);
+}
+
+/**
+ * mei_cl_notify_fop2req - convert fop to proper request
+ *
+ * @fop: client notification start response command
+ *
+ * Return: MEI_HBM_NOTIFICATION_START/STOP
+ */
+u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
+{
+ if (fop == MEI_FOP_NOTIFY_START)
+ return MEI_HBM_NOTIFICATION_START;
+ else
+ return MEI_HBM_NOTIFICATION_STOP;
+}
+
+/**
+ * mei_cl_notify_req2fop - convert notification request top file operation type
+ *
+ * @req: hbm notification request type
+ *
+ * Return: MEI_FOP_NOTIFY_START/STOP
+ */
+enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
+{
+ if (req == MEI_HBM_NOTIFICATION_START)
+ return MEI_FOP_NOTIFY_START;
+ else
+ return MEI_FOP_NOTIFY_STOP;
+}
+
+/**
+ * mei_cl_irq_notify - send notification request in irq_thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
+ struct list_head *cmpl_list)
+{
+ struct mei_device *dev = cl->dev;
+ u32 msg_slots;
+ int slots;
+ int ret;
+ bool request;
+
+ msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_request));
+ slots = mei_hbuf_empty_slots(dev);
+ if (slots < 0)
+ return -EOVERFLOW;
+
+ if ((u32)slots < msg_slots)
+ return -EMSGSIZE;
+
+ request = mei_cl_notify_fop2req(cb->fop_type);
+ ret = mei_hbm_cl_notify_req(dev, cl, request);
+ if (ret) {
+ cl->status = ret;
+ list_move_tail(&cb->list, cmpl_list);
+ return ret;
+ }
+
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ return 0;
+}
+
+/**
+ * mei_cl_notify_request - send notification stop/start request
+ *
+ * @cl: host client
+ * @fp: associate request with file
+ * @request: 1 for start or 0 for stop
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_notify_request(struct mei_cl *cl,
+ const struct file *fp, u8 request)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ enum mei_cb_file_ops fop_type;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ if (!dev->hbm_f_ev_supported) {
+ cl_dbg(dev, cl, "notifications not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (!mei_cl_is_connected(cl))
+ return -ENODEV;
+
+ 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;
+ }
+
+ fop_type = mei_cl_notify_req2fop(request);
+ cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ if (mei_hbuf_acquire(dev)) {
+ if (mei_hbm_cl_notify_req(dev, cl, request)) {
+ rets = -ENODEV;
+ goto out;
+ }
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ }
+
+ mutex_unlock(&dev->device_lock);
+ wait_event_timeout(cl->wait,
+ cl->notify_en == request ||
+ cl->status ||
+ !mei_cl_is_connected(cl),
+ dev->timeouts.cl_connect);
+ mutex_lock(&dev->device_lock);
+
+ if (cl->notify_en != request && !cl->status)
+ cl->status = -EFAULT;
+
+ 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_notify - raise notification
+ *
+ * @cl: host client
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+void mei_cl_notify(struct mei_cl *cl)
+{
+ struct mei_device *dev;
+
+ if (!cl || !cl->dev)
+ return;
+
+ dev = cl->dev;
+
+ if (!cl->notify_en)
+ return;
+
+ cl_dbg(dev, cl, "notify event");
+ cl->notify_ev = true;
+ if (!mei_cl_bus_notify_event(cl))
+ wake_up_interruptible(&cl->ev_wait);
+
+ if (cl->ev_async)
+ kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
+
+}
+
+/**
+ * mei_cl_notify_get - get or wait for notification event
+ *
+ * @cl: host client
+ * @block: this request is blocking
+ * @notify_ev: true if notification event was received
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
+{
+ struct mei_device *dev;
+ int rets;
+
+ *notify_ev = false;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ if (!dev->hbm_f_ev_supported) {
+ cl_dbg(dev, cl, "notifications not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (!mei_cl_is_connected(cl))
+ return -ENODEV;
+
+ if (cl->notify_ev)
+ goto out;
+
+ if (!block)
+ return -EAGAIN;
+
+ mutex_unlock(&dev->device_lock);
+ rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
+ mutex_lock(&dev->device_lock);
+
+ if (rets < 0)
+ return rets;
+
+out:
+ *notify_ev = cl->notify_ev;
+ cl->notify_ev = false;
+ return 0;
+}
+
+/**
+ * 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, const struct file *fp)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ if (!mei_cl_is_connected(cl))
+ return -ENODEV;
+
+ if (!mei_me_cl_is_active(cl->me_cl)) {
+ cl_err(dev, cl, "no such me client\n");
+ return -ENOTTY;
+ }
+
+ if (mei_cl_is_fixed_address(cl))
+ return 0;
+
+ /* HW currently supports only one pending read */
+ if (cl->rx_flow_ctrl_creds) {
+ mei_cl_set_read_by_fp(cl, fp);
+ return -EBUSY;
+ }
+
+ cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
+ if (!cb)
+ return -ENOMEM;
+
+ mei_cl_set_read_by_fp(cl, fp);
+
+ 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);
+ goto nortpm;
+ }
+
+ rets = 0;
+ if (mei_hbuf_acquire(dev)) {
+ rets = mei_hbm_cl_flow_control_req(dev, cl);
+ if (rets < 0)
+ goto out;
+
+ list_move_tail(&cb->list, &cl->rd_pending);
+ }
+ cl->rx_flow_ctrl_creds++;
+
+out:
+ cl_dbg(dev, cl, "rpm: autosuspend\n");
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+nortpm:
+ if (rets)
+ mei_io_cb_free(cb);
+
+ return rets;
+}
+
+static inline u8 mei_ext_hdr_set_vtag(void *ext, u8 vtag)
+{
+ struct mei_ext_hdr_vtag *vtag_hdr = ext;
+
+ vtag_hdr->hdr.type = MEI_EXT_HDR_VTAG;
+ vtag_hdr->hdr.length = mei_data2slots(sizeof(*vtag_hdr));
+ vtag_hdr->vtag = vtag;
+ vtag_hdr->reserved = 0;
+ return vtag_hdr->hdr.length;
+}
+
+/**
+ * mei_msg_hdr_init - allocate and initialize mei message header
+ *
+ * @cb: message callback structure
+ *
+ * Return: a pointer to initialized header or ERR_PTR on failure
+ */
+static struct mei_msg_hdr *mei_msg_hdr_init(const struct mei_cl_cb *cb)
+{
+ size_t hdr_len;
+ struct mei_ext_meta_hdr *meta;
+ struct mei_msg_hdr *mei_hdr;
+ bool is_ext, is_vtag;
+
+ if (!cb)
+ return ERR_PTR(-EINVAL);
+
+ /* Extended header for vtag is attached only on the first fragment */
+ is_vtag = (cb->vtag && cb->buf_idx == 0);
+ is_ext = is_vtag;
+
+ /* Compute extended header size */
+ hdr_len = sizeof(*mei_hdr);
+
+ if (!is_ext)
+ goto setup_hdr;
+
+ hdr_len += sizeof(*meta);
+ if (is_vtag)
+ hdr_len += sizeof(struct mei_ext_hdr_vtag);
+
+setup_hdr:
+ mei_hdr = kzalloc(hdr_len, GFP_KERNEL);
+ if (!mei_hdr)
+ return ERR_PTR(-ENOMEM);
+
+ mei_hdr->host_addr = mei_cl_host_addr(cb->cl);
+ mei_hdr->me_addr = mei_cl_me_id(cb->cl);
+ mei_hdr->internal = cb->internal;
+ mei_hdr->extended = is_ext;
+
+ if (!is_ext)
+ goto out;
+
+ meta = (struct mei_ext_meta_hdr *)mei_hdr->extension;
+ if (is_vtag) {
+ meta->count++;
+ meta->size += mei_ext_hdr_set_vtag(meta->hdrs, cb->vtag);
+ }
+out:
+ mei_hdr->length = hdr_len - sizeof(*mei_hdr);
+ return mei_hdr;
+}
+
+/**
+ * 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 list_head *cmpl_list)
+{
+ struct mei_device *dev;
+ struct mei_msg_data *buf;
+ struct mei_msg_hdr *mei_hdr = NULL;
+ size_t hdr_len;
+ size_t hbuf_len, dr_len;
+ size_t buf_len;
+ size_t data_len;
+ int hbuf_slots;
+ u32 dr_slots;
+ u32 dma_len;
+ int rets;
+ bool first_chunk;
+ const void *data;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ buf = &cb->buf;
+
+ first_chunk = cb->buf_idx == 0;
+
+ rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
+ if (rets < 0)
+ goto err;
+
+ if (rets == 0) {
+ cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
+ return 0;
+ }
+
+ buf_len = buf->size - cb->buf_idx;
+ data = buf->data + cb->buf_idx;
+ hbuf_slots = mei_hbuf_empty_slots(dev);
+ if (hbuf_slots < 0) {
+ rets = -EOVERFLOW;
+ goto err;
+ }
+
+ hbuf_len = mei_slots2data(hbuf_slots) & MEI_MSG_MAX_LEN_MASK;
+ dr_slots = mei_dma_ring_empty_slots(dev);
+ dr_len = mei_slots2data(dr_slots);
+
+ mei_hdr = mei_msg_hdr_init(cb);
+ if (IS_ERR(mei_hdr)) {
+ rets = PTR_ERR(mei_hdr);
+ mei_hdr = NULL;
+ goto err;
+ }
+
+ cl_dbg(dev, cl, "Extended Header %d vtag = %d\n",
+ mei_hdr->extended, cb->vtag);
+
+ hdr_len = sizeof(*mei_hdr) + mei_hdr->length;
+
+ /**
+ * Split the message only if we can write the whole host buffer
+ * otherwise wait for next time the host buffer is empty.
+ */
+ if (hdr_len + buf_len <= hbuf_len) {
+ data_len = buf_len;
+ mei_hdr->msg_complete = 1;
+ } else if (dr_slots && hbuf_len >= hdr_len + sizeof(dma_len)) {
+ mei_hdr->dma_ring = 1;
+ if (buf_len > dr_len)
+ buf_len = dr_len;
+ else
+ mei_hdr->msg_complete = 1;
+
+ data_len = sizeof(dma_len);
+ dma_len = buf_len;
+ data = &dma_len;
+ } else if ((u32)hbuf_slots == mei_hbuf_depth(dev)) {
+ buf_len = hbuf_len - hdr_len;
+ data_len = buf_len;
+ } else {
+ kfree(mei_hdr);
+ return 0;
+ }
+ mei_hdr->length += data_len;
+
+ if (mei_hdr->dma_ring)
+ mei_dma_ring_write(dev, buf->data + cb->buf_idx, buf_len);
+ rets = mei_write_message(dev, mei_hdr, hdr_len, data, data_len);
+
+ if (rets)
+ goto err;
+
+ cl->status = 0;
+ cl->writing_state = MEI_WRITING;
+ cb->buf_idx += buf_len;
+
+ if (first_chunk) {
+ if (mei_cl_tx_flow_ctrl_creds_reduce(cl)) {
+ rets = -EIO;
+ goto err;
+ }
+ }
+
+ if (mei_hdr->msg_complete)
+ list_move_tail(&cb->list, &dev->write_waiting_list);
+
+ kfree(mei_hdr);
+ return 0;
+
+err:
+ kfree(mei_hdr);
+ cl->status = rets;
+ list_move_tail(&cb->list, cmpl_list);
+ return rets;
+}
+
+/**
+ * mei_cl_write - submit a write cb to mei device
+ * assumes device_lock is locked
+ *
+ * @cl: host client
+ * @cb: write callback with filled data
+ *
+ * Return: number of bytes sent on success, <0 on failure.
+ */
+ssize_t mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
+{
+ struct mei_device *dev;
+ struct mei_msg_data *buf;
+ struct mei_msg_hdr *mei_hdr = NULL;
+ size_t hdr_len;
+ size_t hbuf_len, dr_len;
+ size_t buf_len;
+ size_t data_len;
+ int hbuf_slots;
+ u32 dr_slots;
+ u32 dma_len;
+ ssize_t rets;
+ bool blocking;
+ const void *data;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ if (WARN_ON(!cb))
+ return -EINVAL;
+
+ dev = cl->dev;
+
+ buf = &cb->buf;
+ buf_len = buf->size;
+
+ cl_dbg(dev, cl, "buf_len=%zd\n", buf_len);
+
+ blocking = cb->blocking;
+ data = buf->data;
+
+ rets = pm_runtime_get(dev->dev);
+ if (rets < 0 && rets != -EINPROGRESS) {
+ pm_runtime_put_noidle(dev->dev);
+ cl_err(dev, cl, "rpm: get failed %zd\n", rets);
+ goto free;
+ }
+
+ cb->buf_idx = 0;
+ cl->writing_state = MEI_IDLE;
+
+
+ rets = mei_cl_tx_flow_ctrl_creds(cl);
+ if (rets < 0)
+ goto err;
+
+ mei_hdr = mei_msg_hdr_init(cb);
+ if (IS_ERR(mei_hdr)) {
+ rets = PTR_ERR(mei_hdr);
+ mei_hdr = NULL;
+ goto err;
+ }
+
+ cl_dbg(dev, cl, "Extended Header %d vtag = %d\n",
+ mei_hdr->extended, cb->vtag);
+
+ hdr_len = sizeof(*mei_hdr) + mei_hdr->length;
+
+ if (rets == 0) {
+ cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
+ rets = buf_len;
+ goto out;
+ }
+
+ if (!mei_hbuf_acquire(dev)) {
+ cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
+ rets = buf_len;
+ goto out;
+ }
+
+ hbuf_slots = mei_hbuf_empty_slots(dev);
+ if (hbuf_slots < 0) {
+ buf_len = -EOVERFLOW;
+ goto out;
+ }
+
+ hbuf_len = mei_slots2data(hbuf_slots) & MEI_MSG_MAX_LEN_MASK;
+ dr_slots = mei_dma_ring_empty_slots(dev);
+ dr_len = mei_slots2data(dr_slots);
+
+ if (hdr_len + buf_len <= hbuf_len) {
+ data_len = buf_len;
+ mei_hdr->msg_complete = 1;
+ } else if (dr_slots && hbuf_len >= hdr_len + sizeof(dma_len)) {
+ mei_hdr->dma_ring = 1;
+ if (buf_len > dr_len)
+ buf_len = dr_len;
+ else
+ mei_hdr->msg_complete = 1;
+
+ data_len = sizeof(dma_len);
+ dma_len = buf_len;
+ data = &dma_len;
+ } else {
+ buf_len = hbuf_len - hdr_len;
+ data_len = buf_len;
+ }
+
+ mei_hdr->length += data_len;
+
+ if (mei_hdr->dma_ring)
+ mei_dma_ring_write(dev, buf->data, buf_len);
+ rets = mei_write_message(dev, mei_hdr, hdr_len, data, data_len);
+
+ if (rets)
+ goto err;
+
+ rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
+ if (rets)
+ goto err;
+
+ cl->writing_state = MEI_WRITING;
+ cb->buf_idx = buf_len;
+ /* restore return value */
+ buf_len = buf->size;
+
+out:
+ if (mei_hdr->msg_complete)
+ mei_tx_cb_enqueue(cb, &dev->write_waiting_list);
+ else
+ mei_tx_cb_enqueue(cb, &dev->write_list);
+
+ cb = NULL;
+ 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 ||
+ (!mei_cl_is_connected(cl)));
+ mutex_lock(&dev->device_lock);
+ /* wait_event_interruptible returns -ERESTARTSYS */
+ if (rets) {
+ if (signal_pending(current))
+ rets = -EINTR;
+ goto err;
+ }
+ if (cl->writing_state != MEI_WRITE_COMPLETE) {
+ rets = -EFAULT;
+ goto err;
+ }
+ }
+
+ rets = buf_len;
+err:
+ cl_dbg(dev, cl, "rpm: autosuspend\n");
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+free:
+ mei_io_cb_free(cb);
+
+ kfree(mei_hdr);
+
+ 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)
+{
+ struct mei_device *dev = cl->dev;
+
+ switch (cb->fop_type) {
+ case MEI_FOP_WRITE:
+ mei_tx_cb_dequeue(cb);
+ cl->writing_state = MEI_WRITE_COMPLETE;
+ if (waitqueue_active(&cl->tx_wait)) {
+ wake_up_interruptible(&cl->tx_wait);
+ } else {
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_request_autosuspend(dev->dev);
+ }
+ break;
+
+ case MEI_FOP_READ:
+ mei_cl_add_rd_completed(cl, cb);
+ if (!mei_cl_is_fixed_address(cl) &&
+ !WARN_ON(!cl->rx_flow_ctrl_creds))
+ cl->rx_flow_ctrl_creds--;
+ if (!mei_cl_bus_rx_event(cl))
+ wake_up_interruptible(&cl->rx_wait);
+ break;
+
+ case MEI_FOP_CONNECT:
+ case MEI_FOP_DISCONNECT:
+ case MEI_FOP_NOTIFY_STOP:
+ case MEI_FOP_NOTIFY_START:
+ case MEI_FOP_DMA_MAP:
+ case MEI_FOP_DMA_UNMAP:
+ if (waitqueue_active(&cl->wait))
+ wake_up(&cl->wait);
+
+ break;
+ case MEI_FOP_DISCONNECT_RSP:
+ mei_io_cb_free(cb);
+ mei_cl_set_disconnected(cl);
+ break;
+ default:
+ BUG_ON(0);
+ }
+}
+
+
+/**
+ * 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)
+ mei_cl_set_disconnected(cl);
+}
+EXPORT_SYMBOL_GPL(mei_cl_all_disconnect);
+
+static struct mei_cl *mei_cl_dma_map_find(struct mei_device *dev, u8 buffer_id)
+{
+ struct mei_cl *cl;
+
+ list_for_each_entry(cl, &dev->file_list, link)
+ if (cl->dma.buffer_id == buffer_id)
+ return cl;
+ return NULL;
+}
+
+/**
+ * mei_cl_irq_dma_map - send client dma map request in irq_thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_irq_dma_map(struct mei_cl *cl, struct mei_cl_cb *cb,
+ struct list_head *cmpl_list)
+{
+ struct mei_device *dev = cl->dev;
+ u32 msg_slots;
+ int slots;
+ int ret;
+
+ msg_slots = mei_hbm2slots(sizeof(struct hbm_client_dma_map_request));
+ slots = mei_hbuf_empty_slots(dev);
+ if (slots < 0)
+ return -EOVERFLOW;
+
+ if ((u32)slots < msg_slots)
+ return -EMSGSIZE;
+
+ ret = mei_hbm_cl_dma_map_req(dev, cl);
+ if (ret) {
+ cl->status = ret;
+ list_move_tail(&cb->list, cmpl_list);
+ return ret;
+ }
+
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ return 0;
+}
+
+/**
+ * mei_cl_irq_dma_unmap - send client dma unmap request in irq_thread context
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_irq_dma_unmap(struct mei_cl *cl, struct mei_cl_cb *cb,
+ struct list_head *cmpl_list)
+{
+ struct mei_device *dev = cl->dev;
+ u32 msg_slots;
+ int slots;
+ int ret;
+
+ msg_slots = mei_hbm2slots(sizeof(struct hbm_client_dma_unmap_request));
+ slots = mei_hbuf_empty_slots(dev);
+ if (slots < 0)
+ return -EOVERFLOW;
+
+ if ((u32)slots < msg_slots)
+ return -EMSGSIZE;
+
+ ret = mei_hbm_cl_dma_unmap_req(dev, cl);
+ if (ret) {
+ cl->status = ret;
+ list_move_tail(&cb->list, cmpl_list);
+ return ret;
+ }
+
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ return 0;
+}
+
+static int mei_cl_dma_alloc(struct mei_cl *cl, u8 buf_id, size_t size)
+{
+ cl->dma.vaddr = dmam_alloc_coherent(cl->dev->dev, size,
+ &cl->dma.daddr, GFP_KERNEL);
+ if (!cl->dma.vaddr)
+ return -ENOMEM;
+
+ cl->dma.buffer_id = buf_id;
+ cl->dma.size = size;
+
+ return 0;
+}
+
+static void mei_cl_dma_free(struct mei_cl *cl)
+{
+ cl->dma.buffer_id = 0;
+ dmam_free_coherent(cl->dev->dev,
+ cl->dma.size, cl->dma.vaddr, cl->dma.daddr);
+ cl->dma.size = 0;
+ cl->dma.vaddr = NULL;
+ cl->dma.daddr = 0;
+}
+
+/**
+ * mei_cl_dma_alloc_and_map - send client dma map request
+ *
+ * @cl: host client
+ * @fp: pointer to file structure
+ * @buffer_id: id of the mapped buffer
+ * @size: size of the buffer
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return:
+ * * -ENODEV
+ * * -EINVAL
+ * * -EOPNOTSUPP
+ * * -EPROTO
+ * * -ENOMEM;
+ */
+int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp,
+ u8 buffer_id, size_t size)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ if (!dev->hbm_f_cd_supported) {
+ cl_dbg(dev, cl, "client dma is not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (buffer_id == 0)
+ return -EINVAL;
+
+ if (mei_cl_is_connected(cl))
+ return -EPROTO;
+
+ if (cl->dma_mapped)
+ return -EPROTO;
+
+ if (mei_cl_dma_map_find(dev, buffer_id)) {
+ cl_dbg(dev, cl, "client dma with id %d is already allocated\n",
+ cl->dma.buffer_id);
+ return -EPROTO;
+ }
+
+ 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;
+ }
+
+ rets = mei_cl_dma_alloc(cl, buffer_id, size);
+ if (rets) {
+ pm_runtime_put_noidle(dev->dev);
+ return rets;
+ }
+
+ cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DMA_MAP, fp);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ if (mei_hbuf_acquire(dev)) {
+ if (mei_hbm_cl_dma_map_req(dev, cl)) {
+ rets = -ENODEV;
+ goto out;
+ }
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ }
+
+ cl->status = 0;
+
+ mutex_unlock(&dev->device_lock);
+ wait_event_timeout(cl->wait,
+ cl->dma_mapped || cl->status,
+ dev->timeouts.cl_connect);
+ mutex_lock(&dev->device_lock);
+
+ if (!cl->dma_mapped && !cl->status)
+ cl->status = -EFAULT;
+
+ rets = cl->status;
+
+out:
+ if (rets)
+ mei_cl_dma_free(cl);
+
+ 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_dma_unmap - send client dma unmap request
+ *
+ * @cl: host client
+ * @fp: pointer to file structure
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * Return: 0 on such and error otherwise.
+ */
+int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp)
+{
+ struct mei_device *dev;
+ struct mei_cl_cb *cb;
+ int rets;
+
+ if (WARN_ON(!cl || !cl->dev))
+ return -ENODEV;
+
+ dev = cl->dev;
+
+ if (!dev->hbm_f_cd_supported) {
+ cl_dbg(dev, cl, "client dma is not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ /* do not allow unmap for connected client */
+ if (mei_cl_is_connected(cl))
+ return -EPROTO;
+
+ if (!cl->dma_mapped)
+ return -EPROTO;
+
+ 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_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DMA_UNMAP, fp);
+ if (!cb) {
+ rets = -ENOMEM;
+ goto out;
+ }
+
+ if (mei_hbuf_acquire(dev)) {
+ if (mei_hbm_cl_dma_unmap_req(dev, cl)) {
+ rets = -ENODEV;
+ goto out;
+ }
+ list_move_tail(&cb->list, &dev->ctrl_rd_list);
+ }
+
+ cl->status = 0;
+
+ mutex_unlock(&dev->device_lock);
+ wait_event_timeout(cl->wait,
+ !cl->dma_mapped || cl->status,
+ dev->timeouts.cl_connect);
+ mutex_lock(&dev->device_lock);
+
+ if (cl->dma_mapped && !cl->status)
+ cl->status = -EFAULT;
+
+ rets = cl->status;
+
+ if (!rets)
+ mei_cl_dma_free(cl);
+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;
+}