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diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt b/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt new file mode 100644 index 000000000..5682b2010 --- /dev/null +++ b/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt @@ -0,0 +1,99 @@ +Broadcom BCM2835 GPIO (and pinmux) controller + +The BCM2835 GPIO module is a combined GPIO controller, (GPIO) interrupt +controller, and pinmux/control device. + +Required properties: +- compatible: "brcm,bcm2835-gpio" +- compatible: should be one of: + "brcm,bcm2835-gpio" - BCM2835 compatible pinctrl + "brcm,bcm7211-gpio" - BCM7211 compatible pinctrl + "brcm,bcm2711-gpio" - BCM2711 compatible pinctrl + "brcm,bcm7211-gpio" - BCM7211 compatible pinctrl +- reg: Should contain the physical address of the GPIO module's registers. +- 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: + - bit 0 specifies polarity (0 for normal, 1 for inverted) +- interrupts : The interrupt outputs from the controller. One interrupt per + individual bank followed by the "all banks" interrupt. For BCM7211, an + additional set of per-bank interrupt line and an "all banks" wake-up + interrupt may be specified. +- interrupt-controller: Marks the device node as an interrupt controller. +- #interrupt-cells : Should be 2. + The first cell is the GPIO number. + The second cell is used to specify flags: + bits[3:0] trigger type and level flags: + 1 = low-to-high edge triggered. + 2 = high-to-low edge triggered. + 4 = active high level-sensitive. + 8 = active low level-sensitive. + Valid combinations are 1, 2, 3, 4, 8. + +Please refer to ../gpio/gpio.txt for a general description of GPIO bindings. + +Please refer to pinctrl-bindings.txt in this directory for details of the +common pinctrl bindings used by client devices, including the meaning of the +phrase "pin configuration node". + +Each pin configuration node lists the pin(s) to which it applies, and one or +more of the mux function to select on those pin(s), and pull-up/down +configuration. Each subnode only affects those parameters that are explicitly +listed. In other words, a subnode that lists only a mux function implies no +information about any pull configuration. Similarly, a subnode that lists only +a pul parameter implies no information about the mux function. + +The BCM2835 pin configuration and multiplexing supports the generic bindings. +For details on each properties, you can refer to ./pinctrl-bindings.txt. + +Required sub-node properties: + - pins + - function + +Optional sub-node properties: + - bias-disable + - bias-pull-up + - bias-pull-down + - output-high + - output-low + +Legacy pin configuration and multiplexing binding: +*** (Its use is deprecated, use generic multiplexing and configuration +bindings instead) + +Required subnode-properties: +- brcm,pins: An array of cells. Each cell contains the ID of a pin. Valid IDs + are the integer GPIO IDs; 0==GPIO0, 1==GPIO1, ... 53==GPIO53. + +Optional subnode-properties: +- brcm,function: Integer, containing the function to mux to the pin(s): + 0: GPIO in + 1: GPIO out + 2: alt5 + 3: alt4 + 4: alt0 + 5: alt1 + 6: alt2 + 7: alt3 +- brcm,pull: Integer, representing the pull-down/up to apply to the pin(s): + 0: none + 1: down + 2: up + +Each of brcm,function and brcm,pull may contain either a single value which +will be applied to all pins in brcm,pins, or 1 value for each entry in +brcm,pins. + +Example: + + gpio: gpio { + compatible = "brcm,bcm2835-gpio"; + reg = <0x2200000 0xb4>; + interrupts = <2 17>, <2 19>, <2 18>, <2 20>; + + gpio-controller; + #gpio-cells = <2>; + + interrupt-controller; + #interrupt-cells = <2>; + }; |