[alsa-devel] Regarding alsa-utils commit "alsaucm: add alsa-ucm udev rules for PAZ00 (Toshiba AC100/Dynabook AZ)."
Hi Jaroslav,
I'm updating alsa-utils in OpenEmbedded, and I noticed that there's a new udev rules file, 89-alsa-ucm.rules. It seems to just initialize the mixer settings for particular hardware (Toshiba AC100/Dynabook AZ), and doing that in alsa-utils seems weird. Why does this hardware use a udev rules file for initialization, unlike any other hardware?
I think it would be good to have an explanatory comment in the rules file.
Dne 21. 02. 19 v 11:51 Tanu Kaskinen napsal(a):
Hi Jaroslav,
I'm updating alsa-utils in OpenEmbedded, and I noticed that there's a new udev rules file, 89-alsa-ucm.rules. It seems to just initialize the mixer settings for particular hardware (Toshiba AC100/Dynabook AZ), and doing that in alsa-utils seems weird. Why does this hardware use a udev rules file for initialization, unlike any other hardware?
I was asked to add those rules to the ALSA initialization, so it seems that we have users that does not use any other additional layer to control the hardware and they want to use the standard ALSA applications on top.
Note that there is not only mixer settings, but also the routing settings which most of standard mixer applications don't handle correctly, so it makes sense to do this settings at boot.
Anyway, I am open to any discussion to handle this properly. Nowadays, it seems that the use-case configurations are mandatory to bring the universal hardware drivers (mainly ASoC) to an useable state. We have already alsactl, it may be extended to set the default use case or restore the last one. We can also write special alsactl configs, but it makes sense to keep things only at the one place.
Jaroslav
On Thu, 2019-02-21 at 12:32 +0100, Jaroslav Kysela wrote:
Dne 21. 02. 19 v 11:51 Tanu Kaskinen napsal(a):
Hi Jaroslav,
I'm updating alsa-utils in OpenEmbedded, and I noticed that there's a new udev rules file, 89-alsa-ucm.rules. It seems to just initialize the mixer settings for particular hardware (Toshiba AC100/Dynabook AZ), and doing that in alsa-utils seems weird. Why does this hardware use a udev rules file for initialization, unlike any other hardware?
I was asked to add those rules to the ALSA initialization, so it seems that we have users that does not use any other additional layer to control the hardware and they want to use the standard ALSA applications on top.
Note that there is not only mixer settings, but also the routing settings which most of standard mixer applications don't handle correctly, so it makes sense to do this settings at boot.
Anyway, I am open to any discussion to handle this properly. Nowadays, it seems that the use-case configurations are mandatory to bring the universal hardware drivers (mainly ASoC) to an useable state. We have already alsactl, it may be extended to set the default use case or restore the last one. We can also write special alsactl configs, but it makes sense to keep things only at the one place.
I think there's no "default verb" concept in UCM, so I guess that's the main thing that needs to be added.
participants (2)
-
Jaroslav Kysela -
Tanu Kaskinen