Takashi Iwai wrote:
Right now there is no "elegant" way for this, unfortunately. A common way many drivers use is to remember the rate of the first stream, then add it to hw_constraint of the secondary streams.
Can you give me an example of a driver that does this? I can't seem to find one.
But, this could be also a bit racy (unavoidable due to its design) although practically it seems working.
I've been trying to implement this, but I'm not sure how. I have a couple questions:
1) Which snd_pcm_hw_constraint_xxx function should I use to specify a sample rate or sample size constraint of a single number? I'm thinking snd_pcm_hw_constraint_list().
2) Where should I be calling this function? In my _hw_params() function? What I would like to do is require the constraint to be enforced only when a stream is already playing. That is, if playback is paused, then the capture stream can set any sample rate it wants. Is this doable, or just too complicated?