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Diffstat (limited to 'Documentation/devicetree/bindings/gpio/gpio-i2c.txt')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-i2c.txt | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-i2c.txt b/Documentation/devicetree/bindings/gpio/gpio-i2c.txt new file mode 100644 index 000000000000..ad2743bc65ed --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-i2c.txt @@ -0,0 +1,32 @@ +Device-Tree bindings for gpio i2c driver + +A simple parameterized no-irq of_driven i2c->gpio expander, +cut down from gpio-pcf857x.c to be totally device-tree driven. + +Suitable for any "memory-like" device, where a 1-byte i2c read yields data +which can safely be written back, possibly with a bit changed, with the +effect of changing only the output level of that bit's GPIO pin. + +Required properties: + - compatible = "gpio-i2c" + - reg = i2c-address + - gpio-controller + - #gpio-cells = <1>; + - ngpios = number of pins modeled + +Example nodes: + +&i2c_bus { + gpio1: cpld@6c { + compatible = "gpio-i2c"; + gpio-controller; + reg = <0x6c>; + #gpio-cells = <1>; + ngpios = <160>; // 8bits for each reg 0..0x13 + }; +}; + +_some_device_ { + // pin controlled by bitmask 0x2 of byte 0x4 of gpio1 + enable-gpios = <&gpio1 33>; +} |