hi Clements and all:

2013/8/29 loody miloody@gmail.com:

hi clements:

2013/8/28 Clemens Ladisch clemens@ladisch.de:

...

loody wrote:

...

is it possible to get snd_pcm_hardware information in /proc, /sys or anywhere when usb audio device plug in?

if no, is there api I can take in usermode to get snd_pcm_hardware of this usb audio device?

Something like this? http://download.atmark-techno.com/misc/demos/usb-audio-a500-howto/hw_params....

I download the file and

1. cross-compile it with alsa-lib-1.0.23

but I get below message # ./hw_params no soundcards found...no soundcards found...

Sorry, it is my fault :) I didn't create /dev/snd/xxxx nodes for hw_params to access.

after creating /dev/snd/xxx nodes, I get another problem. hw_params will try to access alsa.conf, which is located my host machine.

# ./hw_params PLAYBACK ALSA lib conf.c:3601:(snd_config_update_r) Cannot access file /media/sdb1/software/linux.sound/alsa-lib-1.0.23.mips.clibc/build/share/alsa/alsa.conf ALSA lib control.c:902:(snd_ctl_open_noupdate) Invalid CTL hw:0 control open (0): No such file or directoryCAPTURE ALSA lib conf.c:3601:(snd_config_update_r) Cannot access file /media/sdb1/software/linux.sound/alsa-lib-1.0.23.mips.clibc/build/share/alsa/alsa.conf ALSA lib control.c:902:(snd_ctl_open_noupdate) Invalid CTL hw:0 control open (0): No such file or directory/ #

Except create the same location on target board, is there any compile option I can use to change the path of alsa.conf for hw_params to look for?

appreciate your help,

hi Clements:

2013/9/8 Clemens Ladisch clemens@ladisch.de:

loody wrote:

...

ALSA lib conf.c:3601:(snd_config_update_r) Cannot access file /media/sdb1/software/linux.sound/alsa-lib-1.0.23.mips.clibc/build/share/alsa/alsa.conf

How exactly did you compile and install alsa-lib?

Attach my config.log for your reference. (after configure successfully, I just type "make" and "make install"

Thanks for your kind help,