Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt

   1 MediaTek display PWM controller
   2
   3 Required properties:
   4  - compatible: should be "mediatek,<name>-disp-pwm":
   5    - "mediatek,mt2701-disp-pwm": found on mt2701 SoC.
   6    - "mediatek,mt6595-disp-pwm": found on mt6595 SoC.
   7    - "mediatek,mt8167-disp-pwm", "mediatek,mt8173-disp-pwm": found on mt8167 SoC.
   8    - "mediatek,mt8173-disp-pwm": found on mt8173 SoC.
   9  - reg: physical base address and length of the controller's registers.
  10  - #pwm-cells: must be 2. See pwm.yaml in this directory for a description of
  11    the cell format.
  12  - clocks: phandle and clock specifier of the PWM reference clock.
  13  - clock-names: must contain the following:
  14    - "main": clock used to generate PWM signals.
  15    - "mm": sync signals from the modules of mmsys.
  16  - pinctrl-names: Must contain a "default" entry.
  17  - pinctrl-0: One property must exist for each entry in pinctrl-names.
  18    See pinctrl/pinctrl-bindings.txt for details of the property values.
  19
  20 Example:
  21         pwm0: pwm@1401e000 {
  22                 compatible = "mediatek,mt8173-disp-pwm",
  23                              "mediatek,mt6595-disp-pwm";
  24                 reg = <0 0x1401e000 0 0x1000>;
  25                 #pwm-cells = <2>;
  26                 clocks = <&mmsys CLK_MM_DISP_PWM026M>,
  27                          <&mmsys CLK_MM_DISP_PWM0MM>;
  28                 clock-names = "main", "mm";
  29                 pinctrl-names = "default";
  30                 pinctrl-0 = <&disp_pwm0_pins>;
  31         };
  32
  33         backlight_lcd: backlight_lcd {
  34                 compatible = "pwm-backlight";
  35                 pwms = <&pwm0 0 1000000>;
  36                 brightness-levels = <
  37                           0  16  32  48  64  80  96 112
  38                         128 144 160 176 192 208 224 240
  39                         255
  40                 >;
  41                 default-brightness-level = <9>;
  42                 power-supply = <&mt6397_vio18_reg>;
  43                 enable-gpios = <&pio 95 GPIO_ACTIVE_HIGH>;
  44         };