[0/2] alsa-lib: -ENODATA documentation

Message

Kai Vehmanen May 29, 2020, 12:28 p.m. UTC

Hello all,

here's patch to document -ENODATA error as a PCM error code.
We have recently merged patches to SOF firmware to use
this error code:
  https://github.com/thesofproject/sof/pull/2918

Some additional background on the use-case:
  https://github.com/thesofproject/sof/issues/2564

In thread "Functionality of pcm_notify in snd-aloop?"
https://mailman.alsa-project.org/pipermail/alsa-devel/2020-April/166974.html

.. we discussed the possibility for ALSA to provide a mechanism
for application to wait for the condition to change, but at least
for the currently known usages, the synchronization responsibility
will be in user-space (UCM file will describe the PCM dependencies).
Anyways, this is orthogonal to documenting -ENODATA, so sending
this now.

Kai Vehmanen (2):
  pcm: add documentation for -ENODATA error code
  pcm: fix spelling in documentation for -EBADFD

 src/pcm/pcm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

Comments

Jaroslav Kysela June 5, 2020, 9:56 a.m. UTC | #1

Dne 29. 05. 20 v 14:28 Kai Vehmanen napsal(a):
> Hello all,
> 
> here's patch to document -ENODATA error as a PCM error code.
> We have recently merged patches to SOF firmware to use
> this error code:
>    https://github.com/thesofproject/sof/pull/2918
> 
> Some additional background on the use-case:
>    https://github.com/thesofproject/sof/issues/2564
> 
> In thread "Functionality of pcm_notify in snd-aloop?"
> https://mailman.alsa-project.org/pipermail/alsa-devel/2020-April/166974.html
> 
> .. we discussed the possibility for ALSA to provide a mechanism
> for application to wait for the condition to change, but at least
> for the currently known usages, the synchronization responsibility
> will be in user-space (UCM file will describe the PCM dependencies).
> Anyways, this is orthogonal to documenting -ENODATA, so sending
> this now.
> 
> Kai Vehmanen (2):
>    pcm: add documentation for -ENODATA error code
>    pcm: fix spelling in documentation for -EBADFD
> 
>   src/pcm/pcm.c | 10 +++++++++-
>   1 file changed, 9 insertions(+), 1 deletion(-)
> 

I applied those two patches, and added a short description that there is
no recovery mechanism and an event mechanism to notify the link availability 
at the moment.

https://github.com/alsa-project/alsa-lib/commit/f3597737defe495f9c618b12507c9528c0ade1ee

						Jaroslav