Re: [PATCH] ALSA: hda: Allow for codec model selection with module param

[Cezary Rojewski <cezary.rojewski@intel.com>]

On 9/15/2026 1:14 PM, Takashi Iwai wrote:
> On Mon, 14 Sep 2026 19:58:05 +0200,
> Cezary Rojewski wrote:
>>
>> On 9/14/2026 6:44 PM, Takashi Iwai wrote:
>>
>>>>>> Model selection allows for customization of codec behaviour and thus
>>>>>> dealing with various problems on very specific configurations. The
>>>>>> parameter already exists but is part of snd_hda_intel specifically.
>>>>>> Non-Intel HDAudio controllers and DSP-capable drivers cannot benefit
>>>>>> from it.
>>>>>>
>>>>>> The common place for all the bus drivers is snd_hda_codec. Add modelname
>>>>>> parameter there and honor it when initializing codec->modelname field.
>>>>>>
>>>>>> Link: https://github.com/thesofproject/linux/issues/5683
>>>>>> Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
>>>>>
>>>>> The handling of the model option is a very long-standing PITA.
>>>>> A few years ago, I proposed a change like:
>>>>>   https://mailman.alsa-project.org/pipermail/alsa-devel/2022-September/206631.html
>>>>> but it didn't reach to agreement.  So I'm not 100% sure whether adding
>>>>> here is the best choice, either.
>>>> Thank you for the link, Takashi.
>>>>
>>>> IMHO patch presented here addresses the feedback. I too prefer
>>>> one-location-for-all approach. Also, I do believe having no option for
>>>> specifying the model is worse than choosing either of the approaches for
>>>> the model selection.
>>>>
>>>> snd_hda_codec module is *everywhere* and given the param is an array, it
>>>> supports even very complicated scenarios when multiple HDAudio codecs
>>>> are engaged.
>>>
>>> The multi-codec is exactly the problem I've been seeing (of course in
>>> addition to the lack of the option in ASoC HD-audio).  You'll have to
>>> be very careful how to pass the option, and it can be even fragile.
>>> That's why I hesitated to take this...
>> By multi-codec I also meant scenarios where one has 2+ codecs from one
>> vendor e.g.: realtek. Having non-array param e.g.: for
>> snd_hda_codec_realtek would not suffice.
> 
> But those 2+ codecs are for the single device, right?  (e.g. driving
> multiple channels with multiple codecs, but all of them are a single
> device for user.)
> 
> In theory, it can be a hotplug device, and in that case, we may have
> two device configurations for multiple codecs of the same codec chip.
> But, that's an exception, and I wonder whether we should care for the
> model option that is mainly used for debugging or workaround.
On reference setups we do anything. 2+ standalone codecs on HDAudio bus
in our lab is not some kind of sorcery. Obviously right now we
workaround the kernel by applying a bunch of patches. But adding a
module param (of type array) covers both: any userspace and any
reference scenario.