Re: [PATCH v4 02/31] drm/i915: Don't register backlight when another backlight should be used

Hans de Goede
2022-08-25T08:54:48Z

Hi All,

On 8/24/22 14:50, Jani Nikula wrote:
> On Wed, 24 Aug 2022, Hans de Goede <hdegoede@redhat.com> wrote:
>> Before this commit when we want userspace to use the acpi_video backlight
>> device we register both the GPU's native backlight device and acpi_video's
>> firmware acpi_video# backlight device. This relies on userspace preferring
>> firmware type backlight devices over native ones.
>>
>> Registering 2 backlight devices for a single display really is
>> undesirable, don't register the GPU's native backlight device when
>> another backlight device should be used.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> drivers/gpu/drm/i915/display/intel_backlight.c | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c
>> index 681ebcda97ad..a4dd7924e0c1 100644
>> --- a/drivers/gpu/drm/i915/display/intel_backlight.c
>> +++ b/drivers/gpu/drm/i915/display/intel_backlight.c
>> @@ -8,6 +8,8 @@
>> #include <linux/pwm.h>
>> #include <linux/string_helpers.h>
>>
>> +#include <acpi/video.h>
>> +
>> #include "intel_backlight.h"
>> #include "intel_backlight_regs.h"
>> #include "intel_connector.h"
>> @@ -952,6 +954,11 @@ int intel_backlight_device_register(struct intel_connector *connector)
>>
>> WARN_ON(panel->backlight.max == 0);
>>
>> + if (!acpi_video_backlight_use_native()) {
>> + DRM_INFO("Skipping intel_backlight registration\n");
>
> Could use drm_info with drm_device.

Ack, fixed for v5.

> Either way,
>
> Reviewed-by: Jani Nikula <jani.nikula@intel.com>

Thank you.

> and ack for merging via whichever tree suits you best.

My plan is to create a branch with the series on top
of 6.0-rc1 and then send a pull-req to all involved trees.

So far there are no conflicts between this branch and drm-tip...

Regards,

Hans

>> + return 0;
>> + }
>> +
>> memset(&props, 0, sizeof(props));
>> props.type = BACKLIGHT_RAW;
>