Re: [alsa-devel] snd_pcm_hw_params_free() immediately after snd_pcm_hw_params() ???

Raymond Yau wrote:

Is there any flags in substream which can indicate snd_xxx_hw_params() was called at first time since snd_xxx_hw_params() were called many times during OSS emulation (probing the supported rates , channels , .... ) ?

There is no such flag. It is the responsibility of the driver to track the resources it has allocated.

If a resource does not depend on the hardware parameters, it might be a better idea to allocate/free it in the open/close callbacks.

Best regards, Clemens