On Fri, 3 Apr 2009, Clemens Ladisch wrote:
Jaroslav Kysela wrote:
Unfortunately, driver may use more complex scenarios like:
- some hardware requires additional firmware - in this case devices might be created, but they are not useable until firmware is loaded
This is only true for drivers that load firmware with a hwdep device instead of using request_firmware(). Is there any driver that has not yet been converted? *grep* ... except usx2y?
Good point.
- dynamic device creation at runtime - for example we have an experimental HDA driver configuration code which might change the arrangement of PCM devices on request from the user space
I would suggest to wait awhile with some small timeout (0.5 sec?) for all devices to get the usual static arrangement working and handle extra dynamic cases, too.
The current implementation of the ALSA framework guarantees that the control device file is that latest one to be created for all the devices created at initialization. Any devices created later depend on some userspace action, so a small timeout won't help in this case.
The timeout might help to let alsactl utility to initialize the soundcard's mixer. But I agree that alsactl should send a HAL message that initial setting was done instead.
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.