VIM3 液晶屏背光PWM更改频率问题

qq123456 · September 9, 2020, 2:43am

VIM3 液晶屏背光PWM默认的是180HZ，请问怎么改到32KHz？

Terry · September 9, 2020, 5:46am

你需要重新修改dts文件，然后编译固件。请问一下，你为什么要更改这个频率？

khadas/linux/blob/khadas-vims-pie/arch/arm/boot/dts/amlogic/mesong12b_skt-panel.dtsi#L674


			bl_name = "backlight_pwm";
			bl_level_default_uboot_kernel = <100 100>;
			bl_level_attr = <255 10 /*max, min*/
				128 128>; /*mid, mid_mapping*/
			bl_ctrl_method = <1>; /* 1=pwm, 2=pwm_combo, 4=extern */
			bl_power_attr = <0 /*en_gpio_index*/
				1 0 /*on_value, off_value*/
				200 200>; /*on_delay(ms), off_delay(ms)*/
			bl_pwm_port = "PWM_AO_C";
			bl_pwm_attr = <1 /*pwm_method*/
				180 /*pwm_freq(pwm:Hz, pwm_vs:multiple of vs)*/
				100 25>; /*duty_max(%), duty_min(%)*/
			bl_pwm_power = <1 1 /*pwm_gpio_index, pwm_gpio_off*/
				10 10>; /*pwm_on_delay(ms), pwm_off_delay(ms)*/
			bl_pwm_en_sequence_reverse = <0>; /* 1 for reverse */
		};
		backlight_1{
			index = <1>;
			bl_name = "bl_extern";
			bl_level_default_uboot_kernel = <100 100>;
			bl_level_attr = <255 10 /*max, min*/