Re: [PATCH v8 03/14] drm/property: add a per-connector luminance flag

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Meaningful code and commit message mismatch regarding the removal of a legacy pointer comparison.
--

commit 80b70d62f813789e09813bc2993a201bc254a202
Author: Mario Limonciello <mario.limonciello@amd.com>

drm/property: add a per-connector luminance flag

The upcoming per-connector LUMINANCE range property needs to accept the
value 0 (to turn the display off on DPMS-off) even when its advertised
minimum is 1. The existing check special-cased a single device-wide
property object, which does not work once every connector owns its own
LUMINANCE property.

Add a kernel-internal is_luminance flag on struct drm_property and key
the value-0 exception off it instead of a pointer comparison. The flag
is not exposed to userspace.

> diff --git a/drivers/gpu/drm/drm_property.c b/drivers/gpu/drm/drm_property.c
> index f38f2c5437e68..adccee10cfde4 100644
> --- a/drivers/gpu/drm/drm_property.c
> +++ b/drivers/gpu/drm/drm_property.c
> @@ -952,6 +952,12 @@ bool drm_property_change_valid_get(struct drm_property *property,
>  	*ref = NULL;
>  
>  	if (drm_property_type_is(property, DRM_MODE_PROP_RANGE)) {
> +		/*
> +		 * Special case for the luminance property: allow 0 to turn the
> +		 * display off even when the normal range starts at 1.
> +		 */
> +		if (property->is_luminance && value == 0 && property->values[1] > 0)
> +			return true;

[Severity: Medium]
Does the commit message need to be updated, or was a code removal missed?

The commit message mentions replacing an existing check and keying the
exception off the new flag "instead of a pointer comparison."

However, this patch only adds the new check using the is_luminance flag in
drm_property_change_valid_get(), but it does not remove any existing legacy
pointer comparison from the function.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260908044035.62093-1-mario.limonciello@amd.com?part=3