Re: [PATCH 2/2] dt-bindings: backlight: document new property default-brightness-level
From: Daniel Thompson <hidden>
Date: 2023-05-26 10:20:41
Also in:
dri-devel, linux-devicetree, linux-leds, lkml
On Fri, May 19, 2023 at 11:05:20PM +0300, Alexandru Ardelean wrote:
quoted hunk ↗ jump to hunk
From: Yannick Fertre <yannick.fertre@foss.st.com> Add documentation for new default-brightness-level property. Reviewed-by: Philippe CORNU <philippe.cornu@foss.st.com> Signed-off-by: Yannick Fertre <yannick.fertre@foss.st.com> Signed-off-by: Alexandru Ardelean <redacted> --- Link to original patch: https://github.com/STMicroelectronics/linux/commit/c4067d7bd883c6fa14ffd49892c4ce663cdafe98 .../bindings/leds/backlight/gpio-backlight.yaml | 9 +++++++++ 1 file changed, 9 insertions(+)diff --git a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml index 584030b6b0b9..b96c08cff0f0 100644 --- a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml +++ b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml@@ -23,6 +23,15 @@ properties: description: enable the backlight at boot. type: boolean + default-brightness-level: + description: + The default brightness level (index into the array defined by the + "brightness-levels" property).
gpio-backlight does not have a brightness-levels array property! I think it is also necessary to improve the docs of both properties to distinguish between the meaning of default-on and default-brightness-level. The result of setting default-on and default-brightness level to zero is that the GPIO will be off (this is correct behaviour but hard to figure out from the current text). default-on is a control that can "enable" the backlight at boot when it is not linked to a display in the DT (e.g. it is mostly for legacy cases). When the backlight is linked to a display then the backlight enable state will be automatically linked to the display enable state instead. default-brightness-level is useful for handling displays that are still readable with the backlight off (e-ink, reflective/ transflexive LCD, etc), otherwise is should be absent or set to 1.
+ $ref: /schemas/types.yaml#/definitions/uint32 + +dependencies: + default-brightness-level: [ "brightness-levels" ]
As above, depending on brightness-levels doesn't make any sense here. Daniel.