Re: [PATCH] ALSA: hda: cs35l41: Fix boost type for HP Dragonfly 13.5 inch G4

[Takashi Iwai]

On Fri, 27 Mar 2026 23:25:15 +0100,
Leonard Lausen wrote:
> 
> The HP Dragonfly 13.5 inch G4 (SSID 103C8B63) has _DSD properties in
> ACPI firmware with valid reset-gpios and cs-gpios for the four CS35L41
> amplifiers on SPI.
> 
> However, the _DSD specifies cirrus,boost-type as Internal (0), while
> the hardware requires External Boost. With Internal Boost configured,
> the amplifiers trigger "Amp short error" when audio is played at
> moderate-to-high volume, eventually shutting down entirely.
> 
> Add a configuration table entry to override the boost type to
> External, similar to the existing workaround for 103C89C6. All GPIO
> indices are set to -1 since the _DSD provides valid reset-gpios and
> cs-gpios.
> 
> Confirmed on BIOS V90 01.11.00 (January 2026), the latest available.
> 
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=219520
> Originally-by: Nicholas Wang <me@xxxxxxxxxxxxx>
> Signed-off-by: Leonard Lausen <leonard@xxxxxxxxx>
> ---
> This is a reworked version of Nicholas Wang's patch from Nov 2024 [1].
> Stefan Binding noted that this laptop should have valid _DSD.
> 
> Analysis of the ACPI DSDT confirms the _DSD exists with valid
> reset-gpios, cs-gpios, and cirrus,speaker-position. However,
> cirrus,boost-type is set to 0 (Internal) while the hardware requires
> External Boost. The cs35l41_hda_parse_acpi() fallback also gets this
> wrong since it infers Internal from the non-zero boost parameters.
> 
> With Internal Boost, all four amps hit "Amp short error" at
> moderate volume. Overriding to External Boost (like 103C89C6)
> resolves the issue. GPIO indices are set to -1 since the _DSD
> provides valid reset-gpios and cs-gpios, addressing Stefan's
> concern about cs_gpio_index.
> 
> Tested on BIOS V90 01.11.00 (Jan 2026, latest available from HP).

Applied to for-next branch now.


thanks,

Takashi