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44 lines
1.2 KiB
44 lines
1.2 KiB
* Single Byte SPI LED Device Driver. |
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The driver can be used for controllers with a very simple SPI protocol: |
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- one LED is controlled by a single byte on MOSI |
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- the value of the byte gives the brightness between two values (lowest to |
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highest) |
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- no return value is necessary (no MISO signal) |
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The value for lowest and highest brightness is dependent on the device and |
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therefore on the compatible string. |
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Depending on the compatible string some special functions (like hardware |
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accelerated blinking) might can be supported too. |
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The driver currently only supports one LED. The properties of the LED are |
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configured in a sub-node in the device node. |
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Required properties: |
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- compatible: should be one of |
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* "ubnt,acb-spi-led" microcontroller (SONiX 8F26E611LA) based device |
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used for example in Ubiquiti airCube ISP |
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Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt |
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apply. |
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LED sub-node properties: |
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- label: |
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see Documentation/devicetree/bindings/leds/common.txt |
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- default-state: |
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see Documentation/devicetree/bindings/leds/common.txt |
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Only "on" and "off" are supported. |
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Example: |
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led-controller@0 { |
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compatible = "ubnt,acb-spi-led"; |
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reg = <0>; |
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spi-max-frequency = <100000>; |
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led { |
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label = "white:status"; |
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default-state = "on"; |
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}; |
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};
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