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9 Mar
2017
9 Mar
'17
5:23 p.m.
Dear ALSA expert ,
I am working with an alsa codec driver where the driver is calling err = snd_pcm_hw_constraint_mask64(substream->runtime, SNDRV_PCM_HW_PARAM_FORMAT, formats); my driver is already setting format before that so I wonder why this function is called? Looks like it is needed to add audio constraints to substreams at open/startup time, but why ? what can be the issue if I do not call it ?
Please explain to me Takashi.
Thanks a lot in advance.