Re: [PATCH] mfd: intel-lpss: add Dell Latitude 7275 to the resource conflict quirk

[Hans de Goede <hansg@kernel.org>]

Hi,

On 8-Sep-26 18:16, D. Manresa wrote:
> The Dell Latitude 7275 2-in-1 has the same BIOS bug as the Latitude 5285:
> the ACPI GEXP device declares an OperationRegion (BAR0) on the GNVS
> variable SB04 and the I2C4 controller (INT3446) builds its _CRS from that
> same variable, so intel_lpss_acpi fails to bind the controller with
> -EBUSY and the front camera sensor (OV5670, INT3479) is never registered
> unless acpi_enforce_resources=lax is passed.
> 
> Add the machine to the DMI table so QUIRK_IGNORE_RESOURCE_CONFLICTS is
> applied to INT3446 on it as well.
> 
> Assisted-by: Claude Code:claude-fable-5-1
> Signed-off-by: D. Manresa <dmanresa@gmail.com>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <johannes.goede@oss.qualcomm.com>


Regards,

Hans



> ---
> Applies on top of "mfd: intel-lpss: add resource conflict quirk for Dell
> Latitude 5285" from Thierry Chatard's v10 series [1]. Thierry, feel free
> to fold this into v11 instead if you prefer.
> 
> The conflict was verified in the 7275 DSDT (BIOS 1.18.0): GEXP has
> OperationRegion (BAR0, SystemMemory, SB04, 0x0208) and INT3446._CRS
> returns LCRS (SMD4, SB04, SIR4). With acpi_enforce_resources=lax, which
> has the same effect as the quirk, the controller binds and the camera
> works with the board data from "platform/x86: int3472: Add TPS68470 board
> data for Dell Latitude 7275" [2]. The distribution kernel here builds
> intel-lpss-acpi in, so this exact patch has not been run yet.
> 
> [1] https://lore.kernel.org/linux-media/20260831160754.9857-2-tchatard@gmail.com/
> [2] https://lore.kernel.org/platform-driver-x86/20260908161445.334910-1-dmanresa@gmail.com/
> 
>  drivers/mfd/intel-lpss-acpi.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> --- a/drivers/mfd/intel-lpss-acpi.c
> +++ b/drivers/mfd/intel-lpss-acpi.c
> @@ -191,6 +191,12 @@ static const struct dmi_system_id intel_lpss_quirk_dmi[] = {
>  			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude 5285"),
>  		},
>  	},
> +	{
> +		.matches = {
> +			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
> +			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude 7275"),
> +		},
> +	},
>  	{ }
>  };
>