xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunMediaTek display PWM controller
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunRequired properties:
4*4882a593Smuzhiyun - compatible: should be "mediatek,<name>-disp-pwm":
5*4882a593Smuzhiyun   - "mediatek,mt2701-disp-pwm": found on mt2701 SoC.
6*4882a593Smuzhiyun   - "mediatek,mt6595-disp-pwm": found on mt6595 SoC.
7*4882a593Smuzhiyun   - "mediatek,mt8173-disp-pwm": found on mt8173 SoC.
8*4882a593Smuzhiyun - reg: physical base address and length of the controller's registers.
9*4882a593Smuzhiyun - #pwm-cells: must be 2. See pwm.yaml in this directory for a description of
10*4882a593Smuzhiyun   the cell format.
11*4882a593Smuzhiyun - clocks: phandle and clock specifier of the PWM reference clock.
12*4882a593Smuzhiyun - clock-names: must contain the following:
13*4882a593Smuzhiyun   - "main": clock used to generate PWM signals.
14*4882a593Smuzhiyun   - "mm": sync signals from the modules of mmsys.
15*4882a593Smuzhiyun - pinctrl-names: Must contain a "default" entry.
16*4882a593Smuzhiyun - pinctrl-0: One property must exist for each entry in pinctrl-names.
17*4882a593Smuzhiyun   See pinctrl/pinctrl-bindings.txt for details of the property values.
18*4882a593Smuzhiyun
19*4882a593SmuzhiyunExample:
20*4882a593Smuzhiyun	pwm0: pwm@1401e000 {
21*4882a593Smuzhiyun		compatible = "mediatek,mt8173-disp-pwm",
22*4882a593Smuzhiyun			     "mediatek,mt6595-disp-pwm";
23*4882a593Smuzhiyun		reg = <0 0x1401e000 0 0x1000>;
24*4882a593Smuzhiyun		#pwm-cells = <2>;
25*4882a593Smuzhiyun		clocks = <&mmsys CLK_MM_DISP_PWM026M>,
26*4882a593Smuzhiyun			 <&mmsys CLK_MM_DISP_PWM0MM>;
27*4882a593Smuzhiyun		clock-names = "main", "mm";
28*4882a593Smuzhiyun		pinctrl-names = "default";
29*4882a593Smuzhiyun		pinctrl-0 = <&disp_pwm0_pins>;
30*4882a593Smuzhiyun	};
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun	backlight_lcd: backlight_lcd {
33*4882a593Smuzhiyun		compatible = "pwm-backlight";
34*4882a593Smuzhiyun		pwms = <&pwm0 0 1000000>;
35*4882a593Smuzhiyun		brightness-levels = <
36*4882a593Smuzhiyun			  0  16  32  48  64  80  96 112
37*4882a593Smuzhiyun			128 144 160 176 192 208 224 240
38*4882a593Smuzhiyun			255
39*4882a593Smuzhiyun		>;
40*4882a593Smuzhiyun		default-brightness-level = <9>;
41*4882a593Smuzhiyun		power-supply = <&mt6397_vio18_reg>;
42*4882a593Smuzhiyun		enable-gpios = <&pio 95 GPIO_ACTIVE_HIGH>;
43*4882a593Smuzhiyun	};
44