Re: [PATCH v3 0/3] Fix CS35L56 amplifier on Intel LPSS SPI with broken ACPI cs-gpios

[Juan Jimenez Carrero]

On Thu, 17 Sep 2026 14:42:18 +0100, Richard Fitzgerald wrote:
> The latest BIOS (01.06.02) is reported to fix the problem:
> https://bugzilla.kernel.org/show_bug.cgi?id=221064#c23

Thanks, Richard. Confirmed on the same machine as my earlier report:

  HP EliteBook 8 G1i 14 inch, DMI board 8D8A, SKU D75TQET#ABE
  BIOS X91 Ver. 01.05.02 -> X91 Ver. 01.06.02 (dated 07/22/2026)

I dumped the ACPI tables before and after the update. The only change
in Scope (\_SB.PC00.SPI0) is the cs-gpios property:

   "cs-gpios",
  -Package (0x01)
  +Package (0x05)
   {
  +    Zero,
  +    GSPK,
  +    Zero,
  +    Zero,
       Zero
   }

CS0 stays on the native chip select and CS1 becomes GpioIo resource 0
of GSPK, which is the same GPIO that 2/3 installs. Device (GSPK) is
unchanged between the two versions.

On 01.06.02 with an unpatched kernel (7.2.5, no out-of-tree modules,
taint 0) both amplifiers probe, the calibration is applied and the
speakers play. The "cs1 >= max 1" error is gone.

With 2/3 and 3/3 still loaded on 01.06.02, the quirk matches the DMI
entry but returns early because cs < num_chipselect, so the series
does no harm on the fixed firmware. On 01.05.02 it is still needed,
and my earlier Tested-by stands for that case.

One small detail in case there is a v4: the DMI entry's .ident says
"HP EliteBook 8 G1i 16 inch", but board 8D8A is also the 14 inch model
I tested on.

Thanks,
Juan