diff options
Diffstat (limited to 'sound/usb/line6/driver.c')
| -rw-r--r-- | sound/usb/line6/driver.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c index 4f096685ed65..7629116f570e 100644 --- a/sound/usb/line6/driver.c +++ b/sound/usb/line6/driver.c @@ -550,6 +550,7 @@ static int line6_hwdep_open(struct snd_hwdep *hw, struct file *file) /* NOTE: hwdep layer provides atomicity here */ line6->messages.active = 1; + line6->messages.nonblock = file->f_flags & O_NONBLOCK ? 1 : 0; return 0; } @@ -579,6 +580,9 @@ line6_hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, while (kfifo_len(&line6->messages.fifo) == 0) { mutex_unlock(&line6->messages.read_lock); + if (line6->messages.nonblock) + return -EAGAIN; + rv = wait_event_interruptible( line6->messages.wait_queue, kfifo_len(&line6->messages.fifo) != 0); @@ -626,11 +630,27 @@ line6_hwdep_write(struct snd_hwdep *hwdep, const char __user *data, long count, return rv; } +static __poll_t +line6_hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait) +{ + __poll_t rv; + struct usb_line6 *line6 = hwdep->private_data; + + poll_wait(file, &line6->messages.wait_queue, wait); + + mutex_lock(&line6->messages.read_lock); + rv = kfifo_len(&line6->messages.fifo) == 0 ? 0 : EPOLLIN | EPOLLRDNORM; + mutex_unlock(&line6->messages.read_lock); + + return rv; +} + static const struct snd_hwdep_ops hwdep_ops = { .open = line6_hwdep_open, .release = line6_hwdep_release, .read = line6_hwdep_read, .write = line6_hwdep_write, + .poll = line6_hwdep_poll, }; /* Insert into circular buffer */ |