Hi, On May 4 2016 22:59, Charles Keepax wrote: > We can't return a negative error code from the poll callback the return > type is unsigned and is checked against the poll specific flags we need > to return POLLERR if we encounter an error. > > Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx> > --- > sound/core/pcm_native.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c > index 9106d8e..c61fd50 100644 > --- a/sound/core/pcm_native.c > +++ b/sound/core/pcm_native.c > @@ -3161,7 +3161,7 @@ static unsigned int snd_pcm_playback_poll(struct file *file, poll_table * wait) > > substream = pcm_file->substream; > if (PCM_RUNTIME_CHECK(substream)) > - return -ENXIO; > + return POLLOUT | POLLWRNORM | POLLERR; > runtime = substream->runtime; > > poll_wait(file, &runtime->sleep, wait); > @@ -3200,7 +3200,7 @@ static unsigned int snd_pcm_capture_poll(struct file *file, poll_table * wait) > > substream = pcm_file->substream; > if (PCM_RUNTIME_CHECK(substream)) > - return -ENXIO; > + return POLLIN | POLLRDNORM | POLLERR; > runtime = substream->runtime; > > poll_wait(file, &runtime->sleep, wait); I agree with the concept of your patch to fix the return value of ALSA PCM core. It should return a value which consists of POLLxxx masks. On the other hand, I think POLLOUT, POLLIN, POLLWRNORM and POLLRDNORM should not be included in the value. PCM_RUNTIME_CHECK() ensures PCM substream or PCM runtime is NULL. This means that subsequent I/O operations are failed, at least for handling PCM frames. I think it better to return 'POLLERR | POLLHUP'. Regards Takashi Sakamoto _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
