Linuxcodec framework Learning

Linuxcodec framework learning-Linux general technology-Linux technology and application information. The following is a detailed description. Recently I have been studying the linux ALSA framework. I am very confused about several member variables in the snd_pcm_runtime struct. I don't know how to use these variables ???

/* -- SW params --*/
Int tstamp_mode;/* mmap timestamp is updated */
Unsigned int period_step;
Snd_pcm_uframes_t start_threshold;
Snd_pcm_uframes_t stop_threshold;
Snd_pcm_uframes_t silence_threshold;/* Silence filling happens when
Noise is nearest than this */
Snd_pcm_uframes_t silence_size;/* Silence filling size */
Snd_pcm_uframes_t boundary;/* pointers wrap point */

Snd_pcm_uframes_t silence_start;/* starting pointer to silence area */
Snd_pcm_uframes_t silence_filled;/* size filled with silence */


Snd_pcm_uframes_t buffer_size;/* buffer size */
Snd_pcm_uframes_t min_align;/* Min alignment for the format */

Snd_pcm_uframes_t hw_ptr_base;/* Position at buffer restart */
Snd_pcm_uframes_t hw_ptr_interrupt;/* Position at interrupt time */



Who can help me explain in detail their usefulness? Although I have an English explanation, I still don't quite understand it ..

Snd_pcm_playback_silence () is a function that has never been understood !!

Please kindly advise !! 445947162@qq.com