Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / interrupt-controller / interrupts.txt

diff --git a/kernel/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt b/kernel/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
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+Specifying interrupt information for devices
+============================================
+
+1) Interrupt client nodes
+-------------------------
+
+Nodes that describe devices which generate interrupts must contain an
+"interrupts" property, an "interrupts-extended" property, or both. If both are
+present, the latter should take precedence; the former may be provided simply
+for compatibility with software that does not recognize the latter. These
+properties contain a list of interrupt specifiers, one per output interrupt. The
+format of the interrupt specifier is determined by the interrupt controller to
+which the interrupts are routed; see section 2 below for details.
+
+  Example:
+       interrupt-parent = <&intc1>;
+       interrupts = <5 0>, <6 0>;
+
+The "interrupt-parent" property is used to specify the controller to which
+interrupts are routed and contains a single phandle referring to the interrupt
+controller node. This property is inherited, so it may be specified in an
+interrupt client node or in any of its parent nodes. Interrupts listed in the
+"interrupts" property are always in reference to the node's interrupt parent.
+
+The "interrupts-extended" property is a special form for use when a node needs
+to reference multiple interrupt parents. Each entry in this property contains
+both the parent phandle and the interrupt specifier. "interrupts-extended"
+should only be used when a device has multiple interrupt parents.
+
+  Example:
+       interrupts-extended = <&intc1 5 1>, <&intc2 1 0>;
+
+2) Interrupt controller nodes
+-----------------------------
+
+A device is marked as an interrupt controller with the "interrupt-controller"
+property. This is a empty, boolean property. An additional "#interrupt-cells"
+property defines the number of cells needed to specify a single interrupt.
+
+It is the responsibility of the interrupt controller's binding to define the
+length and format of the interrupt specifier. The following two variants are
+commonly used:
+
+  a) one cell
+  -----------
+  The #interrupt-cells property is set to 1 and the single cell defines the
+  index of the interrupt within the controller.
+
+  Example:
+
+       vic: intc@10140000 {
+               compatible = "arm,versatile-vic";
+               interrupt-controller;
+               #interrupt-cells = <1>;
+               reg = <0x10140000 0x1000>;
+       };
+
+       sic: intc@10003000 {
+               compatible = "arm,versatile-sic";
+               interrupt-controller;
+               #interrupt-cells = <1>;
+               reg = <0x10003000 0x1000>;
+               interrupt-parent = <&vic>;
+               interrupts = <31>; /* Cascaded to vic */
+       };
+
+  b) two cells
+  ------------
+  The #interrupt-cells property is set to 2 and the first cell defines the
+  index of the interrupt within the controller, while the second cell is used
+  to specify any of the following 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
+
+  Example:
+
+       i2c@7000c000 {
+               gpioext: gpio-adnp@41 {
+                       compatible = "ad,gpio-adnp";
+                       reg = <0x41>;
+
+                       interrupt-parent = <&gpio>;
+                       interrupts = <160 1>;
+
+                       gpio-controller;
+                       #gpio-cells = <1>;
+
+                       interrupt-controller;
+                       #interrupt-cells = <2>;
+
+                       nr-gpios = <64>;
+               };
+
+               sx8634@2b {
+                       compatible = "smtc,sx8634";
+                       reg = <0x2b>;
+
+                       interrupt-parent = <&gpioext>;
+                       interrupts = <3 0x8>;
+
+                       #address-cells = <1>;
+                       #size-cells = <0>;
+
+                       threshold = <0x40>;
+                       sensitivity = <7>;
+               };
+       };