xref: /freebsd/sys/contrib/device-tree/Bindings/leds/leds-lm36274.txt (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1* Texas Instruments LM36274 4-Channel LCD Backlight Driver w/Integrated Bias
2
3The LM36274 is an integrated four-channel WLED driver and LCD bias supply.
4The backlight boost provides the power to bias four parallel LED strings with
5up to 29V total output voltage. The 11-bit LED current is programmable via
6the I2C bus and/or controlled via a logic level PWM input from 60 uA to 30 mA.
7
8Parent device properties are documented in
9Documentation/devicetree/bindings/mfd/ti-lmu.txt
10
11Regulator properties are documented in
12Documentation/devicetree/bindings/regulator/lm363x-regulator.txt
13
14Required backlight properties:
15	- compatible:
16		"ti,lm36274-backlight"
17	- reg : 0
18	- #address-cells : 1
19	- #size-cells : 0
20	- led-sources : Indicates which LED strings will be enabled.
21			Values from 0-3, sources is 0 based so strings will be
22			source value + 1.
23
24Optional backlight properties:
25	- label : see Documentation/devicetree/bindings/leds/common.txt
26	- linux,default-trigger :
27	   see Documentation/devicetree/bindings/leds/common.txt
28
29Example:
30
31HVLED string 1 and 3 are controlled by control bank A and HVLED 2 string is
32controlled by control bank B.
33
34lm36274@11 {
35	compatible = "ti,lm36274";
36	#address-cells = <1>;
37	#size-cells = <0>;
38	reg = <0x11>;
39
40	enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
41
42	regulators {
43		#address-cells = <1>;
44		#size-cells = <0>;
45		compatible = "ti,lm363x-regulator";
46
47		enable-gpios = <&pioC 0 GPIO_ACTIVE_HIGH>,
48			       <&pioC 1 GPIO_ACTIVE_HIGH>;
49
50		vboost {
51			regulator-name = "lcd_boost";
52			regulator-min-microvolt = <4000000>;
53			regulator-max-microvolt = <7150000>;
54			regulator-always-on;
55		};
56
57		vpos {
58			regulator-name = "lcd_vpos";
59			regulator-min-microvolt = <4000000>;
60			regulator-max-microvolt = <6500000>;
61		};
62
63		vneg {
64			regulator-name = "lcd_vneg";
65			regulator-min-microvolt = <4000000>;
66			regulator-max-microvolt = <6500000>;
67		};
68	};
69
70	backlight {
71		#address-cells = <1>;
72		#size-cells = <0>;
73		compatible = "ti,lm36274-backlight";
74
75		led@0 {
76			reg = <0>;
77			led-sources = <0 2>;
78			label = "white:backlight_cluster";
79			linux,default-trigger = "backlight";
80		};
81	};
82};
83
84For more product information please see the link below:
85https://www.ti.com/lit/ds/symlink/lm36274.pdf
86