[0/1] Fix backlight control on Toshiba Satellite Z830

Hi,

First: I'm very new to this whole kernel development thing, so applogies in
advance for any mistakes.

I am submitting a patch that fixes backlight on Toshiba Satellite/Portege
Z830. This is a so called "ultrabook" from 2011. It needs the quirk
video_disable_backlight_sysfs_if. Without it backlight control breaks after
a suspend/resume cycle. However, control via intel_backlight still works.
If I disable acpi_video via acpi_backlight=none however, the backlight
never turns on at all after resume.

Thanks to Hans de Goede for suggesting this fix.

Reference:
* https://www.spinics.net/lists/platform-driver-x86/msg34394.html

Best regards,
Arvid Norlander

Arvid Norlander (1):
  ACPI: video: Add Toshiba Satellite/Portege Z830 quirk

 drivers/acpi/acpi_video.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)


base-commit: 1c23f9e627a7b412978b4e852793c5e3c3efc555

Hi,

On 8/24/22 20:49, Arvid Norlander wrote:
> Toshiba Satellite Z830 needs the quirk video_disable_backlight_sysfs_if
> for proper backlight control after suspend/resume cycles.
> 
> Toshiba Portege Z830 is simply the same laptop rebranded for certain
> markets (I looked through the manual to other language sections to confirm
> this) and thus also needs this quirk.
> 
> Thanks to Hans de Goede for suggesting this fix.
> 
> Link: https://www.spinics.net/lists/platform-driver-x86/msg34394.html
> Signed-off-by: Arvid Norlander <lkml@vorpal.se>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans


> 
> ---
>  drivers/acpi/acpi_video.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
> index 5cbe2196176d..2a4990733cf0 100644
> --- a/drivers/acpi/acpi_video.c
> +++ b/drivers/acpi/acpi_video.c
> @@ -496,6 +496,22 @@ static const struct dmi_system_id video_dmi_table[] = {
>  		DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
>  		},
>  	},
> +	{
> +	 .callback = video_disable_backlight_sysfs_if,
> +	 .ident = "Toshiba Satellite Z830",
> +	 .matches = {
> +		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
> +		DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE Z830"),
> +		},
> +	},
> +	{
> +	 .callback = video_disable_backlight_sysfs_if,
> +	 .ident = "Toshiba Portege Z830",
> +	 .matches = {
> +		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
> +		DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE Z830"),
> +		},
> +	},
>  	/*
>  	 * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
>  	 * but the IDs actually follow the Device ID Scheme.