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+* Texas Instruments - lm3532 White LED driver with ambient light sensing
+capability.
+
+The LM3532 provides the 3 high-voltage, low-side current sinks. The device is
+programmable over an I2C-compatible interface and has independent
+current control for all three channels. The adaptive current regulation
+method allows for different LED currents in each current sink thus allowing
+for a wide variety of backlight and keypad applications.
+
+The main features of the LM3532 include dual ambient light sensor inputs
+each with 32 internal voltage setting resistors, 8-bit logarithmic and linear
+brightness control, dual external PWM brightness control inputs, and up to
+1000:1 dimming ratio with programmable fade in and fade out settings.
+
+Required properties:
+ - compatible : "ti,lm3532"
+ - reg : I2C slave address
+ - #address-cells : 1
+ - #size-cells : 0
+
+Optional properties:
+ - enable-gpios : gpio pin to enable (active high)/disable the device.
+ - ramp-up-us - The Run time ramp rates/step are from one current
+ set-point to another after the device has reached its
+ initial target set point from turn-on
+ - ramp-down-us - The Run time ramp rates/step are from one current
+ set-point to another after the device has reached its
+ initial target set point from turn-on
+ Range for ramp settings: 8us - 65536us
+
+Optional properties if ALS mode is used:
+ - ti,als-vmin - Minimum ALS voltage defined in Volts
+ - ti,als-vmax - Maximum ALS voltage defined in Volts
+ Per the data sheet the max ALS voltage is 2V and the min is 0V
+
+ - ti,als1-imp-sel - ALS1 impedance resistor selection in Ohms
+ - ti,als2-imp-sel - ALS2 impedance resistor selection in Ohms
+ Range for impedance select: 37000 Ohms - 1190 Ohms
+ Values above 37kohms will be set to the "High Impedance" setting
+
+ - ti,als-avrg-time-us - Determines the length of time the device needs to
+ average the two ALS inputs. This is only used if
+ the input mode is LM3532_ALS_INPUT_AVRG.
+ Range: 17920us - 2293760us
+ - ti,als-input-mode - Determines how the device uses the attached ALS
+ devices.
+ 0x00 - ALS1 and ALS2 input average
+ 0x01 - ALS1 Input
+ 0x02 - ALS2 Input
+ 0x03 - Max of ALS1 and ALS2
+
+Required child properties:
+ - reg : Indicates control bank the LED string is controlled by
+ - led-sources : see Documentation/devicetree/bindings/leds/common.txt
+ - ti,led-mode : Defines if the LED strings are manually controlled or
+ if the LED strings are controlled by the ALS.
+ 0x00 - LED strings are I2C controlled via full scale
+ brightness control register
+ 0x01 - LED strings are ALS controlled
+
+Optional LED child properties:
+ - label : see Documentation/devicetree/bindings/leds/common.txt
+ - linux,default-trigger :
+ see Documentation/devicetree/bindings/leds/common.txt
+ - led-max-microamp : Defines the full scale current value for each control
+ bank. The range is from 5000uA-29800uA in increments
+ of 800uA.
+
+Example:
+led-controller@38 {
+ compatible = "ti,lm3532";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x38>;
+
+ enable-gpios = <&gpio6 12 GPIO_ACTIVE_HIGH>;
+ ramp-up-us = <1024>;
+ ramp-down-us = <65536>;
+
+ ti,als-vmin = <0>;
+ ti,als-vmax = <2000>;
+ ti,als1-imp-sel = <4110>;
+ ti,als2-imp-sel = <2180>;
+ ti,als-avrg-time-us = <17920>;
+ ti,als-input-mode = <0x00>;
+
+ led@0 {
+ reg = <0>;
+ led-sources = <2>;
+ ti,led-mode = <1>;
+ led-max-microamp = <21800>;
+ label = ":backlight";
+ linux,default-trigger = "backlight";
+ };
+
+ led@1 {
+ reg = <1>;
+ led-sources = <1>;
+ ti,led-mode = <0>;
+ label = ":kbd_backlight";
+ };
+};
+
+For more product information please see the links below:
+https://www.ti.com/product/LM3532