[PATCH v2 7/8] arm64: dts: mediatek: cherry: Enable keyboard PWM backlight

Chen-Yu Tsai wenst at chromium.org
Mon Jul 25 03:06:01 PDT 2022


On Mon, Jul 25, 2022 at 6:04 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno at collabora.com> wrote:
>
> Il 25/07/22 11:57, Chen-Yu Tsai ha scritto:
> > n Thu, Jul 21, 2022 at 10:53 PM AngeloGioacchino Del Regno
> > <angelogioacchino.delregno at collabora.com> wrote:
> >>
> >> Add a pwm-leds node to enable the PWM controlled keyboard backlight.
> >>
> >> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>
> >> ---
> >>   arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi | 13 +++++++++++++
> >>   1 file changed, 13 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> >> index ca9955a97f8f..9086a440a995 100644
> >> --- a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> >> +++ b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> >> @@ -4,6 +4,7 @@
> >>    */
> >>
> >>   #include <dt-bindings/gpio/gpio.h>
> >> +#include <dt-bindings/leds/common.h>
> >>   #include "mt8195.dtsi"
> >>   #include "mt6359.dtsi"
> >>
> >> @@ -31,6 +32,18 @@ dmic_codec: dmic-codec {
> >>                  wakeup-delay-ms = <50>;
> >>          };
> >>
> >> +       led-controller {
> >> +               compatible = "pwm-leds";
> >> +
> >> +               keyboard_backlight: keyboard-backlight {
> >> +                       default-state = "off";
> >> +                       function = LED_FUNCTION_KBD_BACKLIGHT;
> >> +                       label = "cros_ec::kbd_backlight";
> >> +                       max-brightness = <1023>;
> >> +                       pwms = <&cros_ec_pwm 3>;
> >> +               };
> >> +       };
> >> +
> >
> > This didn't work for me. However using "google,cros-kbd-led-backlight"
> > under the EC did. That might be a better option.
>
> Strange. But okay if there's a better option I'll check that out for v3.

It might be an EC firmware version issue. My devices are all running
test images, and don't automatically update the EC firmware.

For reference, mine is at:

RO:    tomato_v2.0.10686-234e646fd8
        tomato_14268.0.0
RW:    tomato_v2.0.10686-234e646fd8
        tomato_14268.0.0
Build:    tomato_v2.0.10686-234e646fd8 tomato_14268.0.0
        2021-10-07 09:00:32
        @chromeos-ci-legacy-us-central2-d-x32-34-us9d

ChenYu

> Cheers!
> Angelo
>
> >
> > ChenYu
> >
> >>          memory at 40000000 {
> >>                  device_type = "memory";
> >>                  reg = <0 0x40000000 0 0x80000000>;
> >> --
> >> 2.35.1
> >>
> >>
> >> _______________________________________________
> >> linux-arm-kernel mailing list
> >> linux-arm-kernel at lists.infradead.org
> >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>



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