Re: [PATCH 0/2] Fix CSC3551 speaker sound problem for machines without a valid ACPI _DSD

[David Xu]

Hi Takashi,

On Sun, 16 Jul 2023 14:49:18 +0200 you wrote:

> Thanks for the patches.
> 
> I've seen the lots of pains with CS35L41 codec stuff on the recent
> machines.  But, first of all, it still needs to be agreed by Cirrus
> people whether this approach is acceptable.  Judging from the current 
> situation, such workaround appears inevitable, but we need a
> consensus.
> 
> So, Cirrus people, please check this.

Agreed.
 
> Also, some ideas about the current patch set:
> 
> - Do we need yet another listing and check of each ID in another
>   place?  The existing entry in the SSID quirk table is already unique
>   enough to identify which configuration is taken, I suppose.
>
> - The quirk entries can be gathered in patch_realtek.c, and the hw_cfg
>   and other items are overwritten in cs35l41_no_acpi_dsd() when no
>   _DSD is found.  In that way, we can avoid fixing two places for each
>   update.

I do have noticed that the existing entries in patch_realtek.c are enough
for locating the right quirk. However I'm unsure if these entries can 
be moved to that file since the cs35l41 i2c/spi devices are instantiated
by the serial-multi-instantiate driver, and if no proper _DSD is found 
the cs35l41 driver would just fail with no corresponding i2c/spi devices.
I don't know if it is possible for the hda driver to intervene this 
probing process.


> - The workaround is a workaround, and it's fundamentally dangerous.
>   We should warn it in a kernel message.

Agreed. I will update my patches to emit a warning message, however as
Stuart has replied, a patch series which is cleaner is on its way in few 
weeks and I would not submit a new version for now. I am looking forward 
to Cirrus's work. 

Regards,

David.