The front panel LED on the Cubox-i is driven by one of the iMX6 PWM
channels, and is wired between the PWM output and supply.  This means
that outputting a low level results in the LED being turned on, so we
need the duty cycle inverted.

There's a question about whether the output inversion should be at the
pwm or pwm-leds level - setting the output inversion bit in the iMX6
results in a PWM duty cycle of zero outputting logic zero, meaning that
the LED is fully on.  This is undesirable, as it becomes impossible to
turn the LED fully off.

Signed-off-by: Russell King <[email protected]>
---
 arch/arm/boot/dts/imx6qdl-cubox-i.dtsi | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi 
b/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi
index c2a24888a276..7971387c2e13 100644
--- a/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi
@@ -12,6 +12,20 @@
                pinctrl-0 = <&pinctrl_cubox_i_ir>;
        };
 
+       pwmleds {
+               compatible = "pwm-leds";
+               pinctrl-names = "default";
+               pinctrl-0 = <&pinctrl_cubox_i_pwm1>;
+
+               front {
+                       active-low;
+                       default-brightness = <128>;
+                       label = "imx6:red:front";
+                       max-brightness = <248>;
+                       pwms = <&pwm1 0 50000>;
+               };
+       };
+
        regulators {
                compatible = "simple-bus";
 
@@ -82,6 +96,10 @@
                        >;
                };
 
+               pinctrl_cubox_i_pwm1: cubox-i-pwm1-front-led {
+                       fsl,pins = <MX6QDL_PAD_DISP0_DAT8__PWM1_OUT 0x1b0b0>;
+               };
+
                pinctrl_cubox_i_spdif: cubox-i-spdif {
                        fsl,pins = <MX6QDL_PAD_GPIO_17__SPDIF_OUT 0x13091>;
                };
-- 
1.8.3.1

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