diff options
author | Arnd Bergmann <arnd@arndb.de> | 2011-07-17 22:45:41 +0200 |
---|---|---|
committer | Arnd Bergmann <arnd@arndb.de> | 2011-07-17 22:51:35 +0200 |
commit | 382bc10fbe827191218d4eecfaca0995b085dbfd (patch) | |
tree | fc335b59f754a5e4571937499c7296f06f27aba2 /Documentation | |
parent | ea3e643bbf03735f2109c2d18bee6263c2c71498 (diff) | |
parent | 752ad5e82dfd83851e44a2b9da8761994cd7e61c (diff) |
Merge branch 'depends/gpio' into for-next
Conflicts:
arch/arm/mach-imx/mm-imx1.c
arch/arm/mach-imx/mm-imx21.c
arch/arm/mach-imx/mm-imx25.c
arch/arm/mach-imx/mm-imx27.c
arch/arm/mach-imx/mm-imx31.c
arch/arm/mach-imx/mm-imx35.c
arch/arm/mach-mx5/mm.c
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt | 22 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio.txt | 46 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio_nvidia.txt | 8 |
3 files changed, 67 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt b/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt new file mode 100644 index 00000000000..4363ae4b3c1 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/fsl-imx-gpio.txt @@ -0,0 +1,22 @@ +* Freescale i.MX/MXC GPIO controller + +Required properties: +- compatible : Should be "fsl,<soc>-gpio" +- reg : Address and length of the register set for the device +- interrupts : Should be the port interrupt shared by all 32 pins, if + one number. If two numbers, the first one is the interrupt shared + by low 16 pins and the second one is for high 16 pins. +- gpio-controller : Marks the device node as a gpio controller. +- #gpio-cells : Should be two. The first cell is the pin number and + the second cell is used to specify optional parameters (currently + unused). + +Example: + +gpio0: gpio@73f84000 { + compatible = "fsl,imx51-gpio", "fsl,imx31-gpio"; + reg = <0x73f84000 0x4000>; + interrupts = <50 51>; + gpio-controller; + #gpio-cells = <2>; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt index edaa84d288a..4e16ba4feab 100644 --- a/Documentation/devicetree/bindings/gpio/gpio.txt +++ b/Documentation/devicetree/bindings/gpio/gpio.txt @@ -4,17 +4,45 @@ Specifying GPIO information for devices 1) gpios property ----------------- -Nodes that makes use of GPIOs should define them using `gpios' property, -format of which is: <&gpio-controller1-phandle gpio1-specifier - &gpio-controller2-phandle gpio2-specifier - 0 /* holes are permitted, means no GPIO 3 */ - &gpio-controller4-phandle gpio4-specifier - ...>; +Nodes that makes use of GPIOs should specify them using one or more +properties, each containing a 'gpio-list': -Note that gpio-specifier length is controller dependent. + gpio-list ::= <single-gpio> [gpio-list] + single-gpio ::= <gpio-phandle> <gpio-specifier> + gpio-phandle : phandle to gpio controller node + gpio-specifier : Array of #gpio-cells specifying specific gpio + (controller specific) + +GPIO properties should be named "[<name>-]gpios". Exact +meaning of each gpios property must be documented in the device tree +binding for each device. + +For example, the following could be used to describe gpios pins to use +as chip select lines; with chip selects 0, 1 and 3 populated, and chip +select 2 left empty: + + gpio1: gpio1 { + gpio-controller + #gpio-cells = <2>; + }; + gpio2: gpio2 { + gpio-controller + #gpio-cells = <1>; + }; + [...] + chipsel-gpios = <&gpio1 12 0>, + <&gpio1 13 0>, + <0>, /* holes are permitted, means no GPIO 2 */ + <&gpio2 2>; + +Note that gpio-specifier length is controller dependent. In the +above example, &gpio1 uses 2 cells to specify a gpio, while &gpio2 +only uses one. gpio-specifier may encode: bank, pin position inside the bank, whether pin is open-drain and whether pin is logically inverted. +Exact meaning of each specifier cell is controller specific, and must +be documented in the device tree binding for the device. Example of the node using GPIOs: @@ -28,8 +56,8 @@ and empty GPIO flags as accepted by the "qe_pio_e" gpio-controller. 2) gpio-controller nodes ------------------------ -Every GPIO controller node must have #gpio-cells property defined, -this information will be used to translate gpio-specifiers. +Every GPIO controller node must both an empty "gpio-controller" +property, and have #gpio-cells contain the size of the gpio-specifier. Example of two SOC GPIO banks defined as gpio-controller nodes: diff --git a/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt b/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt new file mode 100644 index 00000000000..eb4b530d64e --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt @@ -0,0 +1,8 @@ +NVIDIA Tegra 2 GPIO controller + +Required properties: +- compatible : "nvidia,tegra20-gpio" +- #gpio-cells : Should be two. The first cell is the pin number and the + second cell is used to specify optional parameters: + - bit 0 specifies polarity (0 for normal, 1 for inverted) +- gpio-controller : Marks the device node as a GPIO controller. |