diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c index e1bf54481fd6..9d0b7050c79a 100644 --- a/drivers/misc/mei/main.c +++ b/drivers/misc/mei/main.c @@ -182,32 +182,36 @@ static ssize_t mei_read(struct file *file, char __user *ubuf, goto out; } - if (rets == -EBUSY && - !mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, file)) { - rets = -ENOMEM; + +again: + mutex_unlock(&dev->device_lock); + if (wait_event_interruptible(cl->rx_wait, + !list_empty(&cl->rd_completed) || + !mei_cl_is_connected(cl))) { + if (signal_pending(current)) + return -EINTR; + return -ERESTARTSYS; + } + mutex_lock(&dev->device_lock); + + if (!mei_cl_is_connected(cl)) { + rets = -ENODEV; goto out; } - do { - mutex_unlock(&dev->device_lock); + cb = mei_cl_read_cb(cl, file); + if (!cb) { + /* + * For amthif all the waiters are woken up, + * but only fp with matching cb->fp get the cb, + * the others have to return to wait on read. + */ + if (cl == &dev->iamthif_cl) + goto again; - if (wait_event_interruptible(cl->rx_wait, - (!list_empty(&cl->rd_completed)) || - (!mei_cl_is_connected(cl)))) { - - if (signal_pending(current)) - return -EINTR; - return -ERESTARTSYS; - } - - mutex_lock(&dev->device_lock); - if (!mei_cl_is_connected(cl)) { - rets = -ENODEV; - goto out; - } - - cb = mei_cl_read_cb(cl, file); - } while (!cb); + rets = 0; + goto out; + } copy_buffer: /* now copy the data to user space */