Hi Takashi,
I am developing a USB gadget driver compliant to USB Audio Class Spec 2.0. So I want to open a PCM substream and do some playback of capture, then close them?
I found snd_pcm_open_substream() is for opening a substream and attach it to a file. But in my application, there is no need to open a file before opening a substream.
- Is there any interface for me to open a substream in kernel space without attach to a file? - How to playback and capture in kernel space, use snd_pcm_lib_write and snd_pcm_lib_read? - How to get the snd_pcm_hardware struct from low level driver, because I have to get the hardware configuration of the snd pcm device?
And I am reading the code of OSS emulator in ALSA. It provides some info about the kernel space sound card programming.
Thanks a lot -Bryan