On 23-07-20, 14:38, Takashi Iwai wrote:
On Tue, 21 Jul 2020 19:00:01 +0200, Srinivas Kandagatla wrote:
For gapless playback it is possible that each track can have different codec profile with same decoder, for example we have WMA album, we may have different tracks as WMA v9, WMA v10 and so on Or if DSP's like QDSP have abililty to switch decoders on single stream for each track, then this call could be used to set new codec parameters.
Existing code does not allow to change this profile while doing gapless playback.
This patchset adds new SNDRV_COMPRESS_SET_CODEC_PARAMS IOCTL along with flags in capablity structure to allow userspace to set this new parameters required which switching codec profile, either for gapless or cross fade usecase.
One idea that came up at the previous audio conference regarding this implementation was to just allow SET_PARAMS during the stream is running (only if the driver sets the capability) instead of introducing yet a new ioctl and an ops. Would it make sense?
That does sound good but only issue would be that we need to somehow mark/document that buffer info is useless and would be discarded, how do we do that?
I have no big objection to add a new ioctl if other people agree, though.
thanks,
Takashi