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]> =-DO NOT APPLY-= 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 64daa3b311f6..d9fbd7ff17df 100644 =-DO NOT APPLY-= a/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi =+DO NOT APPLY+= b/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi @@ -12,6 +12,20 @@ pinctrl-0 = <&pinctrl_cubox_i_ir>; }; =+DO NOT APPLY+= pwmleds { =+DO NOT APPLY+= compatible = "pwm-leds"; =+DO NOT APPLY+= pinctrl-names = "default"; =+DO NOT APPLY+= pinctrl-0 = <&pinctrl_cubox_i_pwm1>; =+DO NOT APPLY+= =+DO NOT APPLY+= front { =+DO NOT APPLY+= active-low; =+DO NOT APPLY+= default-brightness = <128>; =+DO NOT APPLY+= label = "imx6:red:front"; =+DO NOT APPLY+= max-brightness = <248>; =+DO NOT APPLY+= pwms = <&pwm1 0 50000>; =+DO NOT APPLY+= }; =+DO NOT APPLY+= }; =+DO NOT APPLY+= regulators { compatible = "simple-bus"; @@ -88,6 +102,10 @@ >; }; =+DO NOT APPLY+= pinctrl_cubox_i_pwm1: cubox-i-pwm1-front-led { =+DO NOT APPLY+= fsl,pins = <MX6QDL_PAD_DISP0_DAT8__PWM1_OUT 0x1b0b0>; =+DO NOT APPLY+= }; =+DO NOT APPLY+= pinctrl_cubox_i_spdif: cubox-i-spdif { fsl,pins = <MX6QDL_PAD_GPIO_17__SPDIF_OUT 0x1b0b0>; }; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
