diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-grgpio.txt | 26 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt | 47 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-omap.txt | 7 |
3 files changed, 78 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt new file mode 100644 index 0000000..e466598 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt @@ -0,0 +1,26 @@ +Aeroflex Gaisler GRGPIO General Purpose I/O cores. + +The GRGPIO GPIO core is available in the GRLIB VHDL IP core library. + +Note: In the ordinary environment for the GRGPIO core, a Leon SPARC system, +these properties are built from information in the AMBA plug&play. + +Required properties: + +- name : Should be "GAISLER_GPIO" or "01_01a" + +- reg : Address and length of the register set for the device + +- interrupts : Interrupt numbers for this device + +Optional properties: + +- nbits : The number of gpio lines. If not present driver assumes 32 lines. + +- irqmap : An array with an index for each gpio line. An index is either a valid + index into the interrupts property array, or 0xffffffff that indicates + no irq for that line. Driver provides no interrupt support if not + present. + +For further information look in the documentation for the GLIB IP core library: +http://www.gaisler.com/products/grlib/grip.pdf diff --git a/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt new file mode 100644 index 0000000..629d0ef --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt @@ -0,0 +1,47 @@ +Microchip MCP2308/MCP23S08/MCP23017/MCP23S17 driver for +8-/16-bit I/O expander with serial interface (I2C/SPI) + +Required properties: +- compatible : Should be + - "mcp,mcp23s08" for 8 GPIO SPI version + - "mcp,mcp23s17" for 16 GPIO SPI version + - "mcp,mcp23008" for 8 GPIO I2C version or + - "mcp,mcp23017" for 16 GPIO I2C version of the chip +- #gpio-cells : Should be two. + - first cell is the pin number + - second cell is used to specify flags. Flags are currently unused. +- gpio-controller : Marks the device node as a GPIO controller. +- reg : For an address on its bus. I2C uses this a the I2C address of the chip. + SPI uses this to specify the chipselect line which the chip is + connected to. The driver and the SPI variant of the chip support + multiple chips on the same chipselect. Have a look at + mcp,spi-present-mask below. + +Required device specific properties (only for SPI chips): +- mcp,spi-present-mask : This is a present flag, that makes only sense for SPI + chips - as the name suggests. Multiple SPI chips can share the same + SPI chipselect. Set a bit in bit0-7 in this mask to 1 if there is a + chip connected with the corresponding spi address set. For example if + you have a chip with address 3 connected, you have to set bit3 to 1, + which is 0x08. mcp23s08 chip variant only supports bits 0-3. It is not + possible to mix mcp23s08 and mcp23s17 on the same chipselect. Set at + least one bit to 1 for SPI chips. +- spi-max-frequency = The maximum frequency this chip is able to handle + +Example I2C: +gpiom1: gpio@20 { + compatible = "mcp,mcp23017"; + gpio-controller; + #gpio-cells = <2>; + reg = <0x20>; +}; + +Example SPI: +gpiom1: gpio@0 { + compatible = "mcp,mcp23s17"; + gpio-controller; + #gpio-cells = <2>; + spi-present-mask = <0x01>; + reg = <0>; + spi-max-frequency = <1000000>; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio-omap.txt b/Documentation/devicetree/bindings/gpio/gpio-omap.txt index bff51a2..1b524c0 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-omap.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-omap.txt @@ -20,8 +20,11 @@ Required properties: 8 = active low level-sensitive. OMAP specific properties: -- ti,hwmods: Name of the hwmod associated to the GPIO: - "gpio<X>", <X> being the 1-based instance number from the HW spec +- ti,hwmods: Name of the hwmod associated to the GPIO: + "gpio<X>", <X> being the 1-based instance number + from the HW spec. +- ti,gpio-always-on: Indicates if a GPIO bank is always powered and + so will never lose its logic state. Example: |