ARM: at91/aic: add irq domain and device tree support
Add an irqdomain for the AIC interrupt controller.
The device tree support is mapping the registers and
is using the irq_domain_add_legacy() to manage hwirq
translation.
The documentation is describing the meaning of the
two cells required for using this "interrupt-controller"
in a device tree node.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/Documentation/devicetree/bindings/arm/atmel-aic.txt b/Documentation/devicetree/bindings/arm/atmel-aic.txt
new file mode 100644
index 0000000..aabca4f
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/atmel-aic.txt
@@ -0,0 +1,38 @@
+* Advanced Interrupt Controller (AIC)
+
+Required properties:
+- compatible: Should be "atmel,<chip>-aic"
+- interrupt-controller: Identifies the node as an interrupt controller.
+- interrupt-parent: For single AIC system, it is an empty property.
+- #interrupt-cells: The number of cells to define the interrupts. It sould be 2.
+ The first cell is the IRQ number (aka "Peripheral IDentifier" on datasheet).
+ 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.
+ Default flag for internal sources should be set to 4 (active high).
+- reg: Should contain AIC registers location and length
+
+Examples:
+ /*
+ * AIC
+ */
+ aic: interrupt-controller@fffff000 {
+ compatible = "atmel,at91rm9200-aic";
+ interrupt-controller;
+ interrupt-parent;
+ #interrupt-cells = <2>;
+ reg = <0xfffff000 0x200>;
+ };
+
+ /*
+ * An interrupt generating device that is wired to an AIC.
+ */
+ dma: dma-controller@ffffec00 {
+ compatible = "atmel,at91sam9g45-dma";
+ reg = <0xffffec00 0x200>;
+ interrupts = <21 4>;
+ };
