From: Chen-Yu Tsai <[email protected]> The LCD backlight on the A23/A33 Q8 format tablets is enabled with a GPIO controlled regulator, and brightness controlled with the SoC's PWM controller.
The backlight is powered from the AXP223 PMIC's DC1SW output, which is not supported yet. A proper bootloader is required to enable it. The brightness levels are arbitrary. The FEX files do not have such information. As such, actual brightness levels may differ from device to device. Signed-off-by: Chen-Yu Tsai <[email protected]> Signed-off-by: Hans de Goede <[email protected]> --- arch/arm/boot/dts/sun8i-q8-common.dtsi | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/arch/arm/boot/dts/sun8i-q8-common.dtsi b/arch/arm/boot/dts/sun8i-q8-common.dtsi index 6f8a8bb..f342736 100644 --- a/arch/arm/boot/dts/sun8i-q8-common.dtsi +++ b/arch/arm/boot/dts/sun8i-q8-common.dtsi @@ -41,11 +41,24 @@ */ #include "sunxi-q8-common.dtsi" +#include <dt-bindings/pwm/pwm.h> + / { aliases { serial0 = &r_uart; }; + backlight: backlight { + compatible = "pwm-backlight"; + pinctrl-names = "default"; + pinctrl-0 = <&bl_en_pin_q8>; + pwms = <&pwm 0 50000 PWM_POLARITY_INVERTED>; + brightness-levels = <0 10 20 30 40 50 60 70 80 90 100>; + default-brightness-level = <8>; + enable-gpios = <&pio 7 6 GPIO_ACTIVE_HIGH>; /* PH6 */ + /* backlight is powered by AXP223 DC1SW */ + }; + chosen { stdout-path = "serial0:115200n8"; }; @@ -62,6 +75,13 @@ }; &pio { + bl_en_pin_q8: bl_en_pin@0 { + allwinner,pins = "PH6"; + allwinner,function = "gpio_in"; + allwinner,drive = <SUN4I_PINCTRL_10_MA>; + allwinner,pull = <SUN4I_PINCTRL_NO_PULL>; + }; + mmc0_cd_pin_q8: mmc0_cd_pin@0 { allwinner,pins = "PB4"; allwinner,function = "gpio_in"; -- 2.4.3 -- 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
