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+APM X-Gene Standby GPIO controller bindings
+
+This is a gpio controller in the standby domain. It also supports interrupt in
+some particular pins which are sourced to its parent interrupt controller
+as diagram below:
+ +-----------------+
+ | X-Gene standby |
+ | GPIO controller +------ GPIO_0
++------------+ | | ...
+| Parent IRQ | EXT_INT_0 | +------ GPIO_8/EXT_INT_0
+| controller | (SPI40) | | ...
+| (GICv2) +--------------+ +------ GPIO_[N+8]/EXT_INT_N
+| | ... | |
+| | EXT_INT_N | +------ GPIO_[N+9]
+| | (SPI[40 + N])| | ...
+| +--------------+ +------ GPIO_MAX
++------------+ +-----------------+
+
+Required properties:
+- compatible: "apm,xgene-gpio-sb" for the X-Gene Standby GPIO controller
+- reg: Physical base address and size of the controller's registers
+- #gpio-cells: Should be two.
+ - first cell is the pin number
+ - second cell is used to specify the gpio polarity:
+ 0 = active high
+ 1 = active low
+- gpio-controller: Marks the device node as a GPIO controller.
+- interrupts: The EXT_INT_0 parent interrupt resource must be listed first.
+- interrupt-cells: Should be two.
+ - first cell is 0-N coresponding for EXT_INT_0 to EXT_INT_N.
+ - second cell is used to specify flags.
+- interrupt-controller: Marks the device node as an interrupt controller.
+- apm,nr-gpios: Optional, specify number of gpios pin.
+- apm,nr-irqs: Optional, specify number of interrupt pins.
+- apm,irq-start: Optional, specify lowest gpio pin support interrupt.
+
+Example:
+ sbgpio: gpio@17001000{
+ compatible = "apm,xgene-gpio-sb";
+ reg = <0x0 0x17001000 0x0 0x400>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupts = <0x0 0x28 0x1>,
+ <0x0 0x29 0x1>,
+ <0x0 0x2a 0x1>,
+ <0x0 0x2b 0x1>,
+ <0x0 0x2c 0x1>,
+ <0x0 0x2d 0x1>;
+ interrupt-parent = <&gic>;
+ #interrupt-cells = <2>;
+ interrupt-controller;
+ apm,nr-gpios = <22>;
+ apm,nr-irqs = <6>;
+ apm,irq-start = <8>;
+ };
+
+ testuser {
+ compatible = "example,testuser";
+ /* Use the GPIO_13/EXT_INT_5 line as an active high triggered
+ * level interrupt
+ */
+ interrupts = <5 4>;
+ interrupt-parent = <&sbgpio>;
+ };