- 根目录:
- drivers
- misc
- mei
- client.c
/*
*
* 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_by_uuid - locate me client by uuid
*
* @dev: mei device
* @uuid: me client uuid
*
* Locking: called under "dev->device_lock" lock
*
* Return: me client or NULL if not found
*/
struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev,
const uuid_le *uuid)
{
struct mei_me_client *me_cl;
list_for_each_entry(me_cl, &dev->me_clients, list)
if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0)
return me_cl;
return NULL;
}
/**
* mei_me_cl_by_id - locate me client by client id
*
* @dev: the device structure
* @client_id: me client id
*
* Locking: called under "dev->device_lock" lock
*
* Return: me client or NULL if not found
*/
struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
{
struct mei_me_client *me_cl;
list_for_each_entry(me_cl, &dev->me_clients, list)
if (me_cl->client_id == client_id)
return me_cl;
return NULL;
}
/**
* mei_me_cl_by_uuid_id - locate me client by client id and uuid
*
* @dev: the device structure
* @uuid: me client uuid
* @client_id: me client id
*
* Locking: called under "dev->device_lock" lock
*
* Return: me client or NULL if not found
*/
struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
const uuid_le *uuid, u8 client_id)
{
struct mei_me_client *me_cl;
list_for_each_entry(me_cl, &dev->me_clients, list)
if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0 &&
me_cl->client_id == client_id)
return me_cl;
return NULL;
}
/**
* mei_me_cl_remove - remove me client matching uuid and client_id
*
* @dev: the device structure
* @uuid: me client uuid
* @client_id: me client address
*/
void mei_me_cl_remove(struct mei_device *dev, const uuid_le *uuid, u8 client_id)
{
struct mei_me_client *me_cl, *next;
list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) {
if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0 &&
me_cl->client_id == client_id) {
list_del(&me_cl->list);
kfree(me_cl);
break;
}
}
}
/**
* 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_list_flush - removes 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;
struct mei_cl_cb *next;
/* enable removing everything if no cl is specified */
list_for_each_entry_safe(cb, next, &list->list, list) {
if (!cl || (cb->cl && mei_cl_cmp_id(cl, cb->cl))) {
list_del(&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_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;
kfree(cb->request_buffer.data);
kfree(cb->response_buffer.data);
kfree(cb);
}
/**
* mei_io_cb_init - allocate and initialize io callback
*
* @cl: mei client
* @fp: pointer to file structure
*
* Return: mei_cl_cb pointer or NULL;
*/
struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp)
{
struct mei_cl_cb *cb;
cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
if (!cb)
return NULL;
mei_io_list_init(cb);
cb->file_object = fp;
cb->cl = cl;
cb->buf_idx = 0;
return cb;
}
/**
* mei_io_cb_alloc_req_buf - allocate request 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_req_buf(struct mei_cl_cb *cb, size_t length)
{
if (!cb)
return -EINVAL;
if (length == 0)
return 0;
cb->request_buffer.data = kmalloc(length, GFP_KERNEL);
if (!cb->request_buffer.data)
return -ENOMEM;
cb->request_buffer.size = length;
return 0;
}
/**
* mei_io_cb_alloc_resp_buf - allocate response 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_resp_buf(struct mei_cl_cb *cb, size_t length)
{
if (!cb)
return -EINVAL;
if (length == 0)
return 0;
cb->response_buffer.data = kmalloc(length, GFP_KERNEL);
if (!cb->response_buffer.data)
return -ENOMEM;
cb->response_buffer.size = length;
return 0;
}
/**
* mei_cl_flush_queues - flushes queue lists belonging to cl.
*
* @cl: host client
*
* Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
*/
int mei_cl_flush_queues(struct mei_cl *cl)
{
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_flush(&cl->dev->read_list, cl);
mei_io_list_free(&cl->dev->write_list, cl);
mei_io_list_free(&cl->dev->write_waiting_list, cl);
mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
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->link);
INIT_LIST_HEAD(&cl->device_link);
cl->reading_state = MEI_IDLE;
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_find_read_cb - find this cl's callback in the read list
*
* @cl: host client
*
* Return: cb on success, NULL on error
*/
struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
{
struct mei_device *dev = cl->dev;
struct mei_cl_cb *cb;
list_for_each_entry(cb, &dev->read_list.list, list)
if (mei_cl_cmp_id(cl, cb->cl))
return cb;
return NULL;
}
/** mei_cl_link: allocate host id in the host map
*
* @cl - host client
* @id - fixed host id or -1 for generic one
*
* Return: 0 on success
* -EINVAL on incorrect values
* -ENONET if client not found
*/
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;
struct mei_client_properties *props;
mutex_lock(&dev->device_lock);
list_for_each_entry(me_cl, &dev->me_clients, list) {
props = &me_cl->props;
if (!uuid_le_cmp(props->protocol_name, mei_amthif_guid))
mei_amthif_host_init(dev);
else if (!uuid_le_cmp(props->protocol_name, mei_wd_guid))
mei_wd_host_init(dev);
else if (!uuid_le_cmp(props->protocol_name, mei_nfc_guid))
mei_nfc_host_init(dev);
}
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 ||
dev->pg_event == MEI_PG_EVENT_WAIT) {
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, NULL);
if (!cb) {
rets = -ENOMEM;
goto free;
}
cb->fop_type = MEI_FOP_DISCONNECT;
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, file);
if (!cb) {
rets = -ENOMEM;
goto out;
}
cb->fop_type = MEI_FOP_CONNECT;
/* run hbuf acquire last so we don't have to undo */
if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
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 (cl->state != MEI_FILE_CONNECTED) {
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_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;
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_id(dev, 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) {
if (WARN_ON(me_cl->props.single_recv_buf == 0))
return -EINVAL;
return 1;
}
return 0;
}
/**
* 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;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
me_cl = mei_me_cl_by_id(dev, 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))
return -EINVAL;
me_cl->mei_flow_ctrl_creds--;
} else {
if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
return -EINVAL;
cl->mei_flow_ctrl_creds--;
}
return 0;
}
/**
* mei_cl_read_start - the start read client message function.
*
* @cl: host client
* @length: number of bytes to read
*
* Return: 0 on success, <0 on failure.
*/
int mei_cl_read_start(struct mei_cl *cl, size_t length)
{
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;
if (cl->read_cb) {
cl_dbg(dev, cl, "read is pending.\n");
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;
}
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, NULL);
if (!cb) {
rets = -ENOMEM;
goto out;
}
/* always allocate at least client max message */
length = max_t(size_t, length, me_cl->props.max_msg_length);
rets = mei_io_cb_alloc_resp_buf(cb, length);
if (rets)
goto out;
cb->fop_type = MEI_FOP_READ;
if (mei_hbuf_acquire(dev)) {
rets = mei_hbm_cl_flow_control_req(dev, cl);
if (rets < 0)
goto out;
list_add_tail(&cb->list, &dev->read_list.list);
} else {
list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
}
cl->read_cb = cb;
out:
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
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->request_buffer;
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->request_buffer.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;
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->request_buffer;
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->fop_type = MEI_FOP_WRITE;
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;
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 &&
MEI_READING == cl->reading_state) {
cl->reading_state = MEI_READ_COMPLETE;
if (waitqueue_active(&cl->rx_wait))
wake_up_interruptible(&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);
}