On 23/01/2026 12:11, [email protected] wrote: > > > On 20-01-2026 20:01, Krzysztof Kozlowski wrote: >> On 20/01/2026 13:50, Sudarshan Shetty wrote: >>> Update the gpio-backlight binding to support configurations that require >>> more than one GPIO for enabling/disabling the backlight. >> >> >> Why? Which devices need it? How a backlight would have three enable >> GPIOs? I really do not believe, so you need to write proper hardware >> justification. >> > > To clarify our hardware setup: > the panel requires one GPIO for the backlight enable signal, and it > also has a PWM input. Since the QCS615 does not provide a PWM controller > for this use case, the PWM input is connected to a GPIO that is driven > high to provide a constant 100% duty cycle, as explained in the link > below. > https://lore.kernel.org/all/[email protected]/T/#m93ca4e5c7bf055715ed13316d91f0cd544244cf5
That's not an enable gpio, but PWM. You write bindings for this device, not for something else - like your board. > >>> >>> Signed-off-by: Sudarshan Shetty <[email protected]> >>> --- >>> .../leds/backlight/gpio-backlight.yaml | 24 +++++++++++++++++-- >>> 1 file changed, 22 insertions(+), 2 deletions(-) >>> >>> diff --git >>> a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >>> b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >>> index 584030b6b0b9..4e4a856cbcd7 100644 >>> --- a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >>> +++ b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >>> @@ -16,8 +16,18 @@ properties: >>> const: gpio-backlight >>> >>> gpios: >>> - description: The gpio that is used for enabling/disabling the >>> backlight. >>> - maxItems: 1 >>> + description: | >>> + The gpio that is used for enabling/disabling the backlight. >>> + Multiple GPIOs can be specified for panels that require several >>> + enable signals. All GPIOs are controlled together. >>> + type: array >> >> There is no such syntax in the bindings, from where did you get it? Type >> is already defined. >> >> items: >> minItems: 1 >> maxItems: 3 >> >> >>> + minItems: 1 >>> + items: >>> + type: array >>> + minItems: 3 >>> + maxItems: 3 >>> + items: >>> + type: integer >> >> All this is some odd stuff - just to be clear, don't send us LLM output. >> I don't want to waste my time to review microslop. >> >> Was it done with help of Microslop? >> > > I understand now that the schema changes I proposed were not correct, How such code could be even created... Just in case, do you understand that Microslop and LLM is waste of our time? > and I will address this in the next patch series. My intention was to > check whether the gpio-backlight binding could support more than one > enable-type GPIO. > Could you please advise what would be an appropriate maximum number of > GPIOs for gpio-backlight in such a scenario? For example, would allowing > 2 GPIOs be acceptable, or should this case be handled in a different way? We have plenty of examples for this, but anyway you won't need it because this is not an enable GPIO. Best regards, Krzysztof
