[alsa-devel] [PATCH] compress: add support for gapless playback

[Takashi Iwai]

At Tue, 12 Feb 2013 22:35:47 -0800,
Vinod Koul wrote:
> 
> On Wed, Feb 13, 2013 at 07:23:32AM +0100, Takashi Iwai wrote:
> > At Tue, 12 Feb 2013 10:31:55 -0800,
> > Vinod Koul wrote:
> > > 
> > > From: Jeeja KP <jeeja.kp at intel.com>
> > > 
> > > this add new API for sound compress to support gapless playback.
> > > As noted in Documentation change, we add API to send metadata of encoder and
> > > padding delay to DSP. Also add API for indicating EOF and switching to
> > > subsequent track
> > > 
> > > Also bump the compress API version
> > > 
> > > Signed-off-by: Jeeja KP <jeeja.kp at intel.com>
> > > Signed-off-by: Vinod Koul <vinod.koul at intel.com>
> > > ---
> > >  v3:
> > > - Change back to ioctl struct with padding
> > 
> > But this makes difficult to know which parameter is unavailable in
> > this kernel, as already mentioned in the thread.  You need to add
> > another ioctl or add a mask in the struct.  Or, take back to single
> > key/value pairs, so user can see the -ENOENT or such error for
> > non-existing parameters.
> Right, but we have the API version.

But what if a driver doesn't support a particular metadata?
Or would you mandate for every driver to support all metadata?


Takashi

> Wouldnt it be okay to use API version to
> find what kernel supports, of course it doesnt scale well as many more params
> are added.
> 
> --
> ~Vinod
>