gpio: Add Netlogic XLP GPIO devicetree bindings documentation

Provide documentation for Netlogic XLP SoCs GPIO controller DTS bindings.

Signed-off-by: Kamlakant Patel <kamlakant.patel@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/Documentation/devicetree/bindings/gpio/gpio-xlp.txt b/Documentation/devicetree/bindings/gpio/gpio-xlp.txt
new file mode 100644 (file)
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+++ b/Documentation/devicetree/bindings/gpio/gpio-xlp.txt
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+Netlogic XLP Family GPIO
+========================
+
+This GPIO driver is used for following Netlogic XLP SoCs:
+       XLP832, XLP316, XLP208, XLP980, XLP532
+
+Required properties:
+-------------------
+
+- compatible: Should be one of the following:
+  - "netlogic,xlp832-gpio": For Netlogic XLP832
+  - "netlogic,xlp316-gpio": For Netlogic XLP316
+  - "netlogic,xlp208-gpio": For Netlogic XLP208
+  - "netlogic,xlp980-gpio": For Netlogic XLP980
+  - "netlogic,xlp532-gpio": For Netlogic XLP532
+- reg: Physical base address and length of the controller's registers.
+- #gpio-cells: Should be two. The first cell is the pin number and the second
+  cell is used to specify optional parameters (currently unused).
+- gpio-controller: Marks the device node as a GPIO controller.
+- nr-gpios: Number of GPIO pins supported by the controller.
+- interrupt-cells: Should be two. The first cell is the GPIO Number. The
+  second cell is used to specify flags. The following subset of flags is
+  supported:
+  - trigger type:
+       1 = low to high edge triggered.
+       2 = high to low edge triggered.
+       4 = active high level-sensitive.
+       8 = active low level-sensitive.
+- interrupts: Interrupt number for this device.
+- interrupt-parent: phandle of the parent interrupt controller.
+- interrupt-controller: Identifies the node as an interrupt controller.
+
+Example:
+
+       gpio: xlp_gpio@34000 {
+               compatible = "netlogic,xlp316-gpio";
+               reg = <0 0x34100 0x1000
+                      0 0x35100 0x1000>;
+               #gpio-cells = <2>;
+               gpio-controller;
+               nr-gpios = <57>;
+
+               #interrupt-cells = <2>;
+               interrupt-parent = <&pic>;
+               interrupts = <39>;
+               interrupt-controller;
+       };