xref: /freebsd/sys/contrib/device-tree/Bindings/pwm/pwm-lp3943.txt (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1TI/National Semiconductor LP3943 PWM controller
2
3Required properties:
4  - compatible: "ti,lp3943-pwm"
5  - #pwm-cells: Should be 2. See pwm.yaml in this directory for a
6                description of the cells format.
7                Note that this hardware limits the period length to the
8                range 6250~1600000.
9  - ti,pwm0 or ti,pwm1: Output pin number(s) for PWM channel 0 or 1.
10    0 = output 0
11    1 = output 1
12    .
13    .
14    15 = output 15
15
16Example:
17PWM 0 is for RGB LED brightness control
18PWM 1 is for brightness control of LP8557 backlight device
19
20&i2c3 {
21	lp3943@60 {
22		compatible = "ti,lp3943";
23		reg = <0x60>;
24
25		/*
26		 * PWM 0 : output 8, 9 and 10
27		 * PWM 1 : output 15
28		 */
29		pwm3943: pwm {
30			compatible = "ti,lp3943-pwm";
31			#pwm-cells = <2>;
32			ti,pwm0 = <8 9 10>;
33			ti,pwm1 = <15>;
34		};
35	};
36
37};
38
39/* LEDs control with PWM 0 of LP3943 */
40pwmleds {
41	compatible = "pwm-leds";
42	rgb {
43		label = "indi::rgb";
44		pwms = <&pwm3943 0 10000>;
45		max-brightness = <255>;
46	};
47};
48
49&i2c4 {
50	/* Backlight control with PWM 1 of LP3943 */
51	backlight@2c {
52		compatible = "ti,lp8557";
53		reg = <0x2c>;
54
55		pwms = <&pwm3943 1 10000>;
56		pwm-names = "lp8557";
57	};
58};
59