[U-Boot] [PATCH 03/21] dm: tegra: Bring in GPIO device tree binding

[Simon Glass]

At present the tegra GPIO driver does not fully support the existing device
tree binding, but add the binding file to cover the existing partial support.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 .../gpio/nvidia,tegra20-gpio.txt                   | 40 ++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 doc/device-tree-bindings/gpio/nvidia,tegra20-gpio.txt

diff --git a/doc/device-tree-bindings/gpio/nvidia,tegra20-gpio.txt b/doc/device-tree-bindings/gpio/nvidia,tegra20-gpio.txt
new file mode 100644
index 0000000..023c952
--- /dev/null
+++ b/doc/device-tree-bindings/gpio/nvidia,tegra20-gpio.txt
@@ -0,0 +1,40 @@
+NVIDIA Tegra GPIO controller
+
+Required properties:
+- compatible : "nvidia,tegra<chip>-gpio"
+- reg : Physical base address and length of the controller's registers.
+- interrupts : The interrupt outputs from the controller. For Tegra20,
+  there should be 7 interrupts specified, and for Tegra30, there should
+  be 8 interrupts specified.
+- #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.
+- #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.
+- interrupt-controller : Marks the device node as an interrupt controller.
+
+Example:
+
+gpio: gpio at 6000d000 {
+	compatible = "nvidia,tegra20-gpio";
+	reg = < 0x6000d000 0x1000 >;
+	interrupts = < 0 32 0x04
+		       0 33 0x04
+		       0 34 0x04
+		       0 35 0x04
+		       0 55 0x04
+		       0 87 0x04
+		       0 89 0x04 >;
+	#gpio-cells = <2>;
+	gpio-controller;
+	#interrupt-cells = <2>;
+	interrupt-controller;
+};
-- 
2.2.0.rc0.207.ga3a616c