Dne 08. 04. 21 v 22:01 Jaroslav Kysela napsal(a):
Dne 08. 04. 21 v 21:41 Pierre-Louis Bossart napsal(a):
Yes, I'm talking about rules which depends on the sound driver specific sysfs attributes (you can match the modified /sys/module/*/parameters here).
you lost me with 'match the modified parameters' wording. who matches and who modifies those parameters?
You can probably add something like this to the sound-card.rules:
SUBSYSTEMS=="pci",ATTR{device/driver/module}=="snd_soc_sof_sdw", ATTR{device/driver/module/../snd_sof_pci/parameters/tplg_path}=="intel/sof-tplg/pdm1", DO_SOMETHING_HERE
DO_SOMETHING_HERE may be ATTR{longname}="My Long Name" for example when my change is accepted.
Humm, not sure this can work due to dependencies.
The machine device is neither an ACPI nor PCI one. It's a platform device.
When the PCI device is detected, the PCI core will call the SOF driver probe, which will first try and boot the firmware, and then create the platform device. That results in the probe of the machine driver which creates the card, but that happens *after* booting the firmware.
the DSP firmware is setup starting here:
https://elixir.bootlin.com/linux/latest/source/sound/soc/sof/core.c#L138
and the machine device is created almost last, after registering the ASoC components.
https://elixir.bootlin.com/linux/latest/source/sound/soc/sof/core.c#L234
when the card is created, it's too late to change the firmware path or any firmware-related parameters.
I just tried to describe the possible 2nd stage - modify the sysfs attributes when the card with the modified firmware is created (all modules are loaded and initialized). The 1st stage like from Curtis must be retained. It ensures to load the right fw.
SYSTEMS=="pci" checks also parents and card0 links to pci device: card0 -> ../../devices/pci0000:00/0000:00:1f.3/sof_sdw/sound/card0 . You can modify this matching anyway - the goal is to run commands for the specific driver and module parameters when the card is loaded (avoid to change the card attributes for other hw).
I'm not an udev expert, so there may be a bug in my suggestion. I also think that the filter may be specified more elegantly (probably using the DRIVER match or so).
Another way to use two rules - use internal udev device environment variable (it seems more straight):
PCI detection level:
SUBSYSTEM=="pci", ATTR{vendor}=="0x8086", ATTR{device}=="0xa0c8", ATTR{class}=="0x040100",ATTRS{[dmi/id]board_name}=="Eldrid", ENV{SOUND_SOF_PROFILE}="MyProfile",...module stuff...
Card instance level (sound-card.rules):
SUBSYSTEMS=="pci",ENV{SOUND_SOF_PROFILE}=="MyProfile",...attr setup...
Jaroslav