At Fri, 18 May 2007 18:00:18 -0700, Allyn, Mark A wrote:
Hello:
I am attempting to do some debugging of a new audio device, and I need to change the number of buffer descriptor list entries from the default of 16 to something much smaller, like 3.
If you're referring to hda-intel, the number of buffer descriptor list isn't fixed there. The smallest size is 2 and the max size is 16. (16 is used for allocation at the driver init time, though.)
I am a bit confused while looking at the code. There seems to be a value labeled SNDRV_PCM_HW_PARAM_BUFFER_SIZE, but I can't figure how it is set. Is this a parameter that is passed as part of the configure prior to doing a make for the driver? Is this a parameter passed to modprobe when loading the driver?
It's a parameter set by user-space at each time the application sets up the PCM after opening the device. The setup is done in hw_params callback.
Takashi