IMX8MP cannot use PWM backlight in U-boot

[caozhixian]

uboot version: 2020.04_5.4.70

Here is my device tree node description:

mipi_dsi_backlight: mipi_dsi_backlight {
compatible = "pwm-backlight";
pwms = <&pwm2 0 100000>;
status = "okay";
brightness-levels = <0 100>;
num-interpolated-steps = <100>;
default-brightness-level = <100>;
};

pinctrl_pwm2: pwm2grp {

fsl,pins = <

MX8MP_IOMUXC_GPIO1_IO09__PWM2_OUT 0x116

>;

};

&pwm2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_pwm2>;
status = "okay";
};

After compiling according to the above configuration, it is found that there is no PWM signal output. Do you want to know whether uboot supports PWM output?  

[AldoG]

Hello,

i.MX8 pwm driver is not supported in u-boot.
if you wants to use it, you will have to add it to u-boot by referring to pwm driver in linux.

Best regards,
Aldo.