summaryrefslogtreecommitdiffstats
path: root/Documentation
diff options
context:
space:
mode:
authorYH Huang <yh.huang@mediatek.com>2015-08-18 09:27:53 +0200
committerThierry Reding <thierry.reding@gmail.com>2015-10-06 16:07:29 +0200
commit3e9e6c28d287a4a2dc62f61cf67654bdae374992 (patch)
tree9510b939c68a63cdcffa671f89afe0d7664d48f1 /Documentation
parentpwm: tipwmss: Enable on TI DRA7x and AM437x (diff)
downloadlinux-3e9e6c28d287a4a2dc62f61cf67654bdae374992.tar.xz
linux-3e9e6c28d287a4a2dc62f61cf67654bdae374992.zip
dt-bindings: pwm: Add MediaTek display PWM bindings
Document the device-tree binding of MediaTek display PWM. The PWM has one channel to control the backlight brightness for display. Both the MT8173 and MT6595 are supported. Signed-off-by: YH Huang <yh.huang@mediatek.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt42
1 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt b/Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt
new file mode 100644
index 000000000000..f8f59baf6b67
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt
@@ -0,0 +1,42 @@
+MediaTek display PWM controller
+
+Required properties:
+ - compatible: should be "mediatek,<name>-disp-pwm":
+ - "mediatek,mt8173-disp-pwm": found on mt8173 SoC.
+ - "mediatek,mt6595-disp-pwm": found on mt6595 SoC.
+ - reg: physical base address and length of the controller's registers.
+ - #pwm-cells: must be 2. See pwm.txt in this directory for a description of
+ the cell format.
+ - clocks: phandle and clock specifier of the PWM reference clock.
+ - clock-names: must contain the following:
+ - "main": clock used to generate PWM signals.
+ - "mm": sync signals from the modules of mmsys.
+ - pinctrl-names: Must contain a "default" entry.
+ - pinctrl-0: One property must exist for each entry in pinctrl-names.
+ See pinctrl/pinctrl-bindings.txt for details of the property values.
+
+Example:
+ pwm0: pwm@1401e000 {
+ compatible = "mediatek,mt8173-disp-pwm",
+ "mediatek,mt6595-disp-pwm";
+ reg = <0 0x1401e000 0 0x1000>;
+ #pwm-cells = <2>;
+ clocks = <&mmsys CLK_MM_DISP_PWM026M>,
+ <&mmsys CLK_MM_DISP_PWM0MM>;
+ clock-names = "main", "mm";
+ pinctrl-names = "default";
+ pinctrl-0 = <&disp_pwm0_pins>;
+ };
+
+ backlight_lcd: backlight_lcd {
+ compatible = "pwm-backlight";
+ pwms = <&pwm0 0 1000000>;
+ brightness-levels = <
+ 0 16 32 48 64 80 96 112
+ 128 144 160 176 192 208 224 240
+ 255
+ >;
+ default-brightness-level = <9>;
+ power-supply = <&mt6397_vio18_reg>;
+ enable-gpios = <&pio 95 GPIO_ACTIVE_HIGH>;
+ };