forked from Minki/linux
45fe3fca6d
Add binding for generic parallel-in/serial-out shift register devices used as GPIO. Signed-off-by: Andrew F. Davis <afd@ti.com> Acked-by: Rob Herring <robh@kernel.org> [Clarified ngpios semantic] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
35 lines
1.0 KiB
Plaintext
35 lines
1.0 KiB
Plaintext
Generic Parallel-in/Serial-out Shift Register GPIO Driver
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This binding describes generic parallel-in/serial-out shift register
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devices that can be used for GPI (General Purpose Input). This includes
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SN74165 serial-out shift registers and the SN65HVS88x series of
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industrial serializers.
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Required properties:
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- compatible : Should be "pisosr-gpio".
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- gpio-controller : Marks the device node as a GPIO controller.
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- #gpio-cells : Should be two. For consumer use see gpio.txt.
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Optional properties:
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- ngpios : Number of used GPIO lines (0..n-1), default is 8.
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- load-gpios : GPIO pin specifier attached to load enable, this
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pin is pulsed before reading from the device to
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load input pin values into the the device.
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For other required and optional properties of SPI slave
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nodes please refer to ../spi/spi-bus.txt.
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Example:
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gpio@0 {
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compatible = "ti,sn65hvs882", "pisosr-gpio";
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gpio-controller;
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#gpio-cells = <2>;
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load-gpios = <&gpio2 23 GPIO_ACTIVE_LOW>;
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reg = <0>;
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spi-max-frequency = <1000000>;
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spi-cpol;
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};
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