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Binding for TI/National Semiconductor LP55xx Led Drivers

Required properties:
- compatible: one of
	national,lp5521
	national,lp5523
	ti,lp55231
	ti,lp5562
	ti,lp8501

- reg: I2C slave address
- clock-mode: Input clock mode, (0: automode, 1: internal, 2: external)

Each child has own specific current settings
- led-cur: Current setting at each led channel (mA x10, 0 if led is not connected)
- max-cur: Maximun current at each led channel.

Optional properties:
- enable-gpio: GPIO attached to the chip's enable pin
- label: Used for naming LEDs
- pwr-sel: LP8501 specific property. Power selection for output channels.
         0: D1~9 are connected to VDD
         1: D1~6 with VDD, D7~9 with VOUT
         2: D1~6 with VOUT, D7~9 with VDD
         3: D1~9 are connected to VOUT

Alternatively, each child can have a specific channel name and trigger:
- chan-name (optional): name of channel
- linux,default-trigger (optional): see
  Documentation/devicetree/bindings/leds/common.txt

example 1) LP5521
3 LED channels, external clock used. Channel names are 'lp5521_pri:channel0',
'lp5521_pri:channel1' and 'lp5521_pri:channel2', with a heartbeat trigger
on channel 0.

lp5521@32 {
	compatible = "national,lp5521";
	reg = <0x32>;
	label = "lp5521_pri";
	clock-mode = /bits/ 8 <2>;

	chan0 {
		led-cur = /bits/ 8 <0x2f>;
		max-cur = /bits/ 8 <0x5f>;
		linux,default-trigger = "heartbeat";
	};

	chan1 {
		led-cur = /bits/ 8 <0x2f>;
		max-cur = /bits/ 8 <0x5f>;
	};

	chan2 {
		led-cur = /bits/ 8 <0x2f>;
		max-cur = /bits/ 8 <0x5f>;
	};
};

example 2) LP5523
9 LED channels with specific name. Internal clock used.
The I2C slave address is configurable with ASEL1 and ASEL0 pins.
Available addresses are 32/33/34/35h.

ASEL1    ASEL0    Address
-------------------------
 GND      GND       32h
 GND      VEN       33h
 VEN      GND       34h
 VEN      VEN       35h

lp5523@32 {
	compatible = "national,lp5523";
	reg = <0x32>;
	clock-mode = /bits/ 8 <1>;

	chan0 {
		chan-name = "d1";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan1 {
		chan-name = "d2";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan2 {
		chan-name = "d3";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan3 {
		chan-name = "d4";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan4 {
		chan-name = "d5";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan5 {
		chan-name = "d6";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan6 {
		chan-name = "d7";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan7 {
		chan-name = "d8";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan8 {
		chan-name = "d9";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};
};

example 3) LP5562
4 channels are defined.

lp5562@30 {
	compatible = "ti,lp5562";
	reg = <0x30>;
	clock-mode = /bits/8 <2>;

	chan0 {
		chan-name = "R";
		led-cur = /bits/ 8 <0x20>;
		max-cur = /bits/ 8 <0x60>;
	};

	chan1 {
		chan-name = "G";
		led-cur = /bits/ 8 <0x20>;
		max-cur = /bits/ 8 <0x60>;
	};

	chan2 {
		chan-name = "B";
		led-cur = /bits/ 8 <0x20>;
		max-cur = /bits/ 8 <0x60>;
	};

	chan3 {
		chan-name = "W";
		led-cur = /bits/ 8 <0x20>;
		max-cur = /bits/ 8 <0x60>;
	};
};

example 4) LP8501
9 channels are defined. The 'pwr-sel' is LP8501 specific property.
Others are same as LP5523.

lp8501@32 {
	compatible = "ti,lp8501";
	reg = <0x32>;
	clock-mode = /bits/ 8 <2>;
	pwr-sel = /bits/ 8 <3>;	/* D1~9 connected to VOUT */

	chan0 {
		chan-name = "d1";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan1 {
		chan-name = "d2";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan2 {
		chan-name = "d3";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan3 {
		chan-name = "d4";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan4 {
		chan-name = "d5";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan5 {
		chan-name = "d6";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan6 {
		chan-name = "d7";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan7 {
		chan-name = "d8";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};

	chan8 {
		chan-name = "d9";
		led-cur = /bits/ 8 <0x14>;
		max-cur = /bits/ 8 <0x20>;
	};
};