Advanced Linux Sound System development

Pavana Sharma | 1 Apr 2004 11:07

RE: Alsa-devel digest, Vol 1 #1786 - 3 msgs

Hi,
I am new to ALSA driver impementation. I am registering the  driver
interface functions like (probe,remove) using driver_register call. I expect
that the probe function will be called in which I am allocating sound card
and registering the card using snd_card_register. When I compile the sound
driver as a static module and boot my kernel I see that the init function in
which I am registering the device is getting called but the probe function
is not getting called.
We see a message from sound/last.c file asla_sound_last_init fucntion where
it searches snd_Cards array to find whether any sound cards are registered.
As our sound card card is not registered(because probe is not getting
called), we see a messaged "No Soundcards found".

Can someone give us some clues like why probe function is not getting
called??

Regards,
Pavana

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Jaroslav Kysela | 1 Apr 2004 11:11

Re: RE: Alsa-devel digest, Vol 1 #1786 - 3 msgs

On Thu, 1 Apr 2004, Pavana Sharma wrote:

> Hi,
> I am new to ALSA driver impementation. I am registering the  driver
> interface functions like (probe,remove) using driver_register call. I expect
> that the probe function will be called in which I am allocating sound card
> and registering the card using snd_card_register. When I compile the sound
> driver as a static module and boot my kernel I see that the init function in
> which I am registering the device is getting called but the probe function
> is not getting called.
> We see a message from sound/last.c file asla_sound_last_init fucntion where
> it searches snd_Cards array to find whether any sound cards are registered.
> As our sound card card is not registered(because probe is not getting
> called), we see a messaged "No Soundcards found".
> 
> Can someone give us some clues like why probe function is not getting
> called??

The probe function is not called from ALSA, but from the kernel subsystem 
like PCI or ISA PnP etc. Check this code.

						Jaroslav

-----
Jaroslav Kysela <perex <at> suse.cz>
Linux Kernel Sound Maintainer
ALSA Project, SuSE Labs

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