/**
* mei_wd_send - sends watch dog message to fw.
*
* @dev: the device structure
*
* Return: 0 if success,
* -EIO when message send fails
* -EINVAL when invalid message is to be sent
* -ENODEV on flow control failure
*/
int mei_wd_send(struct mei_device *dev)
{
struct mei_cl *cl = &dev->wd_cl;
struct mei_msg_hdr hdr;
int ret;
hdr.host_addr = cl->host_client_id;
hdr.me_addr = mei_cl_me_id(cl);
hdr.msg_complete = 1;
hdr.reserved = 0;
hdr.internal = 0;
if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_HDR_SIZE))
hdr.length = MEI_WD_START_MSG_SIZE;
else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_HDR_SIZE))
hdr.length = MEI_WD_STOP_MSG_SIZE;
else {
dev_err(dev->dev, "wd: invalid message is to be sent, aborting\n");
return -EINVAL;
}
ret = mei_write_message(dev, &hdr, dev->wd_data);
if (ret) {
dev_err(dev->dev, "wd: write message failed\n");
return ret;
}
ret = mei_cl_flow_ctrl_reduce(cl);
if (ret) {
dev_err(dev->dev, "wd: flow_ctrl_reduce failed.\n");
return ret;
}
return 0;
}
/*
* mei_wd_ops_ping - wd ping command from the watchdog core.
*
* @wd_dev - watchdog device struct
*
* returns 0 if success, negative errno code for failure
*/
static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
{
struct mei_device *dev;
struct mei_cl *cl;
int ret;
dev = watchdog_get_drvdata(wd_dev);
if (!dev)
return -ENODEV;
cl = &dev->wd_cl;
mutex_lock(&dev->device_lock);
if (cl->state != MEI_FILE_CONNECTED) {
dev_err(&dev->pdev->dev, "wd: not connected.\n");
ret = -ENODEV;
goto end;
}
dev->wd_state = MEI_WD_RUNNING;
ret = mei_cl_flow_ctrl_creds(cl);
if (ret < 0)
goto end;
/* Check if we can send the ping to HW*/
if (ret && mei_hbuf_acquire(dev)) {
dev_dbg(&dev->pdev->dev, "wd: sending ping\n");
if (mei_wd_send(dev)) {
dev_err(&dev->pdev->dev, "wd: send failed.\n");
ret = -EIO;
goto end;
}
if (mei_cl_flow_ctrl_reduce(cl)) {
dev_err(&dev->pdev->dev, "wd: mei_cl_flow_ctrl_reduce() failed.\n");
ret = -EIO;
goto end;
}
} else {
dev->wd_pending = true;
}
end:
mutex_unlock(&dev->device_lock);
return ret;
}
/**
* mei_wd_stop - sends watchdog stop message to fw.
*
* @dev: the device structure
* @preserve: indicate if to keep the timeout value
*
* returns 0 if success,
* -EIO when message send fails
* -EINVAL when invalid message is to be sent
*/
int mei_wd_stop(struct mei_device *dev)
{
int ret;
if (dev->wd_cl.state != MEI_FILE_CONNECTED ||
dev->wd_state != MEI_WD_RUNNING)
return 0;
memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_STOP_MSG_SIZE);
dev->wd_state = MEI_WD_STOPPING;
ret = mei_cl_flow_ctrl_creds(&dev->wd_cl);
if (ret < 0)
goto out;
if (ret && mei_hbuf_acquire(dev)) {
ret = 0;
if (!mei_wd_send(dev)) {
ret = mei_cl_flow_ctrl_reduce(&dev->wd_cl);
if (ret)
goto out;
} else {
dev_err(&dev->pdev->dev, "wd: send stop failed\n");
}
dev->wd_pending = false;
} else {
dev->wd_pending = true;
}
mutex_unlock(&dev->device_lock);
ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
dev->wd_state == MEI_WD_IDLE,
msecs_to_jiffies(MEI_WD_STOP_TIMEOUT));
mutex_lock(&dev->device_lock);
if (dev->wd_state == MEI_WD_IDLE) {
dev_dbg(&dev->pdev->dev, "wd: stop completed ret=%d.\n", ret);
ret = 0;
} else {
if (!ret)
ret = -ETIMEDOUT;
dev_warn(&dev->pdev->dev,
"wd: stop failed to complete ret=%d.\n", ret);
}
out:
return ret;
}
