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authorDavid Daney <david.daney@cavium.com>2012-07-05 12:12:38 -0400
committerRalf Baechle <ralf@linux-mips.org>2012-07-23 08:54:52 -0400
commit736b1c9c957e38b80d2e36b2ed196fa1c07468bc (patch)
tree23603989a3dcd7723a0be7448648bc5f8584ceee /Documentation/devicetree/bindings/gpio
parentab25383983fb8d7786696f5371e75e79c3e9a405 (diff)
MIPS: Octeon: Add device tree source files.
The two device tree files octeon_3xxx.dts and octeon_68xx.dts are trimmed by code in a subsequent patch to reflect the hardware actually present on the board. To this end several properties that are not part of the declared bindings are added to aid in trimming off unwanted nodes. Since the device tree and the code that trims it are bound into the kernel binary, these 'marker' properties never escape into the wild, and are purely an implementation detail of the kernel early boot process. This is done for backwards compatibility with existing boards (identified by a board type enumeration value by their bootloaders). New boards will always pass a device tree from the bootloader, the built-in trees are ignored in this case. Signed-off-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: devicetree-discuss@lists.ozlabs.org Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: linux-kernel@vger.kernel.org Cc: David Daney <david.daney@cavium.com> Patchwork: https://patchwork.linux-mips.org/patch/3937/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
-rw-r--r--Documentation/devicetree/bindings/gpio/cavium-octeon-gpio.txt49
1 files changed, 49 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/cavium-octeon-gpio.txt b/Documentation/devicetree/bindings/gpio/cavium-octeon-gpio.txt
new file mode 100644
index 000000000000..9d6dcd3fe7f9
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/cavium-octeon-gpio.txt
@@ -0,0 +1,49 @@
1* General Purpose Input Output (GPIO) bus.
2
3Properties:
4- compatible: "cavium,octeon-3860-gpio"
5
6 Compatibility with all cn3XXX, cn5XXX and cn6XXX SOCs.
7
8- reg: The base address of the GPIO unit's register bank.
9
10- gpio-controller: This is a GPIO controller.
11
12- #gpio-cells: Must be <2>. The first cell is the GPIO pin.
13
14- interrupt-controller: The GPIO controller is also an interrupt
15 controller, many of its pins may be configured as an interrupt
16 source.
17
18- #interrupt-cells: Must be <2>. The first cell is the GPIO pin
19 connected to the interrupt source. The second cell is the interrupt
20 triggering protocol and may have one of four values:
21 1 - edge triggered on the rising edge.
22 2 - edge triggered on the falling edge
23 4 - level triggered active high.
24 8 - level triggered active low.
25
26- interrupts: Interrupt routing for each pin.
27
28Example:
29
30 gpio-controller@1070000000800 {
31 #gpio-cells = <2>;
32 compatible = "cavium,octeon-3860-gpio";
33 reg = <0x10700 0x00000800 0x0 0x100>;
34 gpio-controller;
35 /* Interrupts are specified by two parts:
36 * 1) GPIO pin number (0..15)
37 * 2) Triggering (1 - edge rising
38 * 2 - edge falling
39 * 4 - level active high
40 * 8 - level active low)
41 */
42 interrupt-controller;
43 #interrupt-cells = <2>;
44 /* The GPIO pin connect to 16 consecutive CUI bits */
45 interrupts = <0 16>, <0 17>, <0 18>, <0 19>,
46 <0 20>, <0 21>, <0 22>, <0 23>,
47 <0 24>, <0 25>, <0 26>, <0 27>,
48 <0 28>, <0 29>, <0 30>, <0 31>;
49 };