Device Tree Bindings for Register Bit LEDs
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Register bit leds are used with syscon multifunctional devices
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where single bits in a certain register can turn on/off a
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single LED. The register bit LEDs appear as children to the
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syscon device, with the proper compatible string. For the
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syscon bindings see:
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Documentation/devicetree/bindings/mfd/syscon.txt
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Each LED is represented as a sub-node of the syscon device. Each
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node's name represents the name of the corresponding LED.
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LED sub-node properties:
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Required properties:
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- compatible : must be "register-bit-led"
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- offset : register offset to the register controlling this LED
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- mask : bit mask for the bit controlling this LED in the register
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typically 0x01, 0x02, 0x04 ...
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Optional properties:
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- label : (optional)
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see Documentation/devicetree/bindings/leds/common.txt
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- linux,default-trigger : (optional)
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see Documentation/devicetree/bindings/leds/common.txt
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- default-state: (optional) The initial state of the LED
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see Documentation/devicetree/bindings/leds/common.txt
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Example:
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syscon: syscon@10000000 {
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compatible = "arm,realview-pb1176-syscon", "syscon";
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reg = <0x10000000 0x1000>;
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led@8.0 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x01>;
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label = "versatile:0";
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linux,default-trigger = "heartbeat";
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default-state = "on";
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};
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led@8.1 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x02>;
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label = "versatile:1";
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linux,default-trigger = "mmc0";
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default-state = "off";
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};
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led@8.2 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x04>;
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label = "versatile:2";
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linux,default-trigger = "cpu0";
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default-state = "off";
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};
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led@8.3 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x08>;
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label = "versatile:3";
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default-state = "off";
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};
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led@8.4 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x10>;
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label = "versatile:4";
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default-state = "off";
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};
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led@8.5 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x20>;
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label = "versatile:5";
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default-state = "off";
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};
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led@8.6 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x40>;
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label = "versatile:6";
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default-state = "off";
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};
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led@8.7 {
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compatible = "register-bit-led";
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offset = <0x08>;
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mask = <0x80>;
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label = "versatile:7";
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default-state = "off";
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};
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};
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