ALSA audio tools amixer, aplay, arecord for recording and playback
https://blog.csdn.net/xiongtiancheng/article/details/80577478
"Proficient in Linux device driver development"-audio driver alsa
https://blog.csdn.net/Explorer_day/article/details/44856507?utm_medium=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.control&dist_request_id= 2477cdb3-9e0d-4bf2-9fa4-7e70c21b2b93&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.control
ALSA analysis
https://blog.csdn.net/zhang_danf/article/details/38824013
Embedded audio programming-use the alsa library
https://blog.csdn.net/wghkemo123/article/details/82152473
Analysis of ALSA Driver under Linux