ARM: dts: AM33XX: Add PWM backlight DT data to am335x-evmsk

PWM output from ecap2 uses as backlight source. Also adds low threshold
value to have a uniform divisions in brightness-levels scales with
inverse polarity.

Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>

diff --git a/arch/arm/boot/dts/am335x-evmsk.dts b/arch/arm/boot/dts/am335x-evmsk.dts
index 338b68188349a044e1b6e730229773fb039878f6..2033a37c86ec25aa68a78eaa762f4d71db1133c3 100644 (file)
--- a/arch/arm/boot/dts/am335x-evmsk.dts
+++ b/arch/arm/boot/dts/am335x-evmsk.dts
@@ -71,6 +71,12 @@
                                0x1b4 (PIN_OUTPUT_PULLDOWN | MUX_MODE3)         /* xdma_event_intr1.clkout2 */
                        >;
                };
+
+               ecap2_pins: backlight_pins {
+                       pinctrl-single,pins = <
+                               0x19c 0x4       /* mcasp0_ahclkr.ecap2_in_pwm2_out MODE4 */
+                       >;
+               };
        };
 
        ocp {
@@ -120,6 +126,16 @@
                                st,max-limit-z = <750>;
                        };
                };
+
+               epwmss2: epwmss@48304000 {
+                       status = "okay";
+
+                       ecap2: ecap@48304100 {
+                               status = "okay";
+                               pinctrl-names = "default";
+                               pinctrl-0 = <&ecap2_pins>;
+                       };
+               };
        };
 
        vbat: fixedregulator@0 {
@@ -199,6 +215,13 @@
                        gpios = <&gpio2 5 GPIO_ACTIVE_HIGH>;
                };
        };
+
+       backlight {
+               compatible = "pwm-backlight";
+               pwms = <&ecap2 0 50000 1>;
+               brightness-levels = <0 58 61 66 75 90 125 170 255>;
+               default-brightness-level = <8>;
+       };
 };
 
 #include "tps65910.dtsi"