c_chmask capture channel mask
c_srate capture sampling rate
c_ssize capture sample size (bytes)
+ c_mute_present capture mute control enable
+ c_volume_present capture volume control enable
+ c_volume_min capture volume control min value (in 1/256 dB)
+ c_volume_max capture volume control max value (in 1/256 dB)
+ c_volume_res capture volume control resolution (in 1/256 dB)
p_chmask playback channel mask
p_srate playback sampling rate
p_ssize playback sample size (bytes)
+ p_mute_present playback mute control enable
+ p_volume_present playback volume control enable
+ p_volume_min playback volume control min value (in 1/256 dB)
+ p_volume_max playback volume control max value (in 1/256 dB)
+ p_volume_res playback volume control resolution (in 1/256 dB)
req_number the number of pre-allocated request
for both capture and playback
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