diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt index daa30174bcc1..3ddc7ccfe5f3 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt @@ -38,12 +38,38 @@ Required device specific properties (only for SPI chips): removed. - spi-max-frequency = The maximum frequency this chip is able to handle -Example I2C: +Optional properties: +- #interrupt-cells : Should be two. + - first cell is the pin number + - second cell is used to specify flags. +- interrupt-controller: Marks the device node as a interrupt controller. +NOTE: The interrupt functionality is only supported for i2c versions of the +chips. The spi chips can also do the interrupts, but this is not supported by +the linux driver yet. + +Optional device specific properties: +- microchip,irq-mirror: Sets the mirror flag in the IOCON register. Devices + with two interrupt outputs (these are the devices ending with 17 and + those that have 16 IOs) have two IO banks: IO 0-7 form bank 1 and + IO 8-15 are bank 2. These chips have two different interrupt outputs: + One for bank 1 and another for bank 2. If irq-mirror is set, both + interrupts are generated regardless of the bank that an input change + occured on. If it is not set, the interrupt are only generated for the + bank they belong to. + On devices with only one interrupt output this property is useless. + +Example I2C (with interrupt): gpiom1: gpio@20 { compatible = "microchip,mcp23017"; gpio-controller; #gpio-cells = <2>; reg = <0x20>; + + interrupt-parent = <&gpio1>; + interrupts = <17 IRQ_TYPE_LEVEL_LOW>; + interrupt-controller; + #interrupt-cells=<2>; + microchip,irq-mirror; }; Example SPI: |