[SRU][OEM-5.6][PATCH 0/1] alsa: should not load sof driver if the internal mic connects to the codec

[Hui Wang]

On 2020/8/5 下午11:33, Anthony Wong wrote:
> Hi Hui,
>
> Hui Wang 於 5/8/2020 上午11:02 寫道:
>> BugLink: https://bugs.launchpad.net/bugs/1890231
>>
>> This issue was introduced by #1872916 ("Support Intel Soundwire
>> in 5.6-OEM Kernel 20.04"), so focal and groovy kernels don't need
>> this fix.
>>
>> [Impact]
>> We found the sof driver instead of hda driver is enabled on a dell
>> machine without soundwire and dmic. This will make gnome show dummy
>> output and users have no audio device to use.
>>
>> [Fix]
>> When we integrated fix for #1872916, we backported 2 patches, these
>> 2 patches enable the sof driver unconditionally for Dell comet lake
>> machines. There is an upstream patch to fix it, let the sof driver
>> enable conditionally on comet lake machines.
>>
>> [Test Case]
>> Boot the kernel with this patch on that dell machine, check the
>> gnome-control-center, all audio devices exist, playback and recording
>> work well.
>>
>> [Regression Risk]
>> On the Dell comet lake machines with dmic, the sof driver should
>> enable. Without this patch, the sof driver will enable unconditionally,
>> but with this patch, the sof driver will enable conditionally, so it
>> is possible to introduce a regression that on Dell comet machines,
>> the sof driver doesn't enable even the machine has dmic
>
> Can you confirm if the DMI_PRODUCT_SKUs listed in your patch, or with 
> the DMIC ACPI check by snd_intel_dsp_check_dmic(), can cover all CML 
> machines we have enabled? If so, would that eliminate the concern of 
> regression?

I have tested it on a Dell machine with pci dev id 0x06c8 and 
DMI_PRODUCT_SKU "0990", it is a soundwire machine, it worked as well as 
before; and tested it on a Dell machine with pci dev id 0x02c8, it is a 
dmic machine, and through snd_intel_dsp_check_dmic() the sof driver is 
enabled, so this machine worked as well as before too.

What I concern is snd_intel_dsp_check_dmic() doesn't work as expected on 
some Dell CML dmic machines we have enabled, in this situation the sof 
driver will not be enabled and the dmic will not work. But this 
possibility is very low since a dmic machine should have a valid dmic 
definition table in the BIOS.

Because I only have 2 Dell CML machines, it is best to test the patch on 
other Dell CML machines we have enabled, I already added this comment in 
the #1890076.

Thanks,

Hui.


>
> Thanks,
> Anthony
>
>>
>> I have tested this patch on a Dell comet lake dmic machines, it worked
>> well.
>>
>>
>> Pierre-Louis Bossart (1):
>>    ALSA: hda: add autodetection for SoundWire
>>
>>   sound/hda/intel-dsp-config.c | 23 ++++++++++++++++++-----
>>   1 file changed, 18 insertions(+), 5 deletions(-)
>>