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| author | Vasily Khoruzhick <anarsoul@gmail.com> | 2020-05-02 21:31:19 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2020-05-02 22:31:03 +0200 |
| commit | 5c2d0de544c39407bf286d33bdcc1fb06a892d8b (patch) | |
| tree | 98ba931efb431902adb526d13520af14c5bb7932 /sound/usb/line6 | |
| parent | ALSA: isa/wavefront: prevent out of bounds write in ioctl (diff) | |
| download | linux-5c2d0de544c39407bf286d33bdcc1fb06a892d8b.tar.xz linux-5c2d0de544c39407bf286d33bdcc1fb06a892d8b.zip | |
ALSA: line6: hwdep: add support for O_NONBLOCK opening mode
Currently line6 hwdep interface ignores O_NONBLOCK flag when
opening device and it renders it somewhat useless when using poll.
Check for O_NONBLOCK flag when opening device and don't block read()
if it is set.
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Link: https://lore.kernel.org/r/20200502193120.79115-2-anarsoul@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/line6')
| -rw-r--r-- | sound/usb/line6/driver.c | 4 | ||||
| -rw-r--r-- | sound/usb/line6/driver.h | 1 |
2 files changed, 5 insertions, 0 deletions
diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c index 4f096685ed65..86adf87d57f0 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); diff --git a/sound/usb/line6/driver.h b/sound/usb/line6/driver.h index e5e572ed5f30..1a4e3700c80c 100644 --- a/sound/usb/line6/driver.h +++ b/sound/usb/line6/driver.h @@ -163,6 +163,7 @@ struct usb_line6 { struct mutex read_lock; wait_queue_head_t wait_queue; unsigned int active:1; + unsigned int nonblock:1; STRUCT_KFIFO_REC_2(LINE6_BUFSIZE_LISTEN * LINE6_RAW_MESSAGES_MAXCOUNT) fifo; } messages; |