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Diffstat (limited to 'Documentation/devicetree/bindings/gpio/gpio.txt')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio.txt | 78 |
1 files changed, 0 insertions, 78 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt deleted file mode 100644 index 4e16ba4feab..00000000000 --- a/Documentation/devicetree/bindings/gpio/gpio.txt +++ /dev/null @@ -1,78 +0,0 @@ -Specifying GPIO information for devices -============================================ - -1) gpios property ------------------ - -Nodes that makes use of GPIOs should specify them using one or more -properties, each containing a 'gpio-list': - - 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: - - node { - gpios = <&qe_pio_e 18 0>; - }; - -In this example gpio-specifier is "18 0" and encodes GPIO pin number, -and empty GPIO flags as accepted by the "qe_pio_e" gpio-controller. - -2) gpio-controller nodes ------------------------- - -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: - - qe_pio_a: gpio-controller@1400 { - #gpio-cells = <2>; - compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank"; - reg = <0x1400 0x18>; - gpio-controller; - }; - - qe_pio_e: gpio-controller@1460 { - #gpio-cells = <2>; - compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank"; - reg = <0x1460 0x18>; - gpio-controller; - }; - - |