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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-09 09:09:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-09 09:09:44 -0700
commit255ae3fbd298f312ce47ff0c7ee9bb6ad002e0f0 (patch)
tree1152a57dbc1fa85f120f1b6eb57e57e99d3420fa /Documentation
parent89c5a9461d02613c829cf9beffdc3d3c6c3df401 (diff)
parentb6ef9161e43ad58c3824bd76dc87716276f0cd70 (diff)
Merge tag 'metag-for-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag
Pull metag architecture changes from James Hogan: - Device tree updates for TZ1090 GPIO drivers merged via GPIO tree. - Add driver for ImgTec PDC irqchip as found in TZ1090 SoC. - Add linux-metag mailing list to MAINTAINERS file. * tag 'metag-for-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: irq-imgpdc: add ImgTec PDC irqchip driver MAINTAINERS: add linux-metag mailing list metag: tz1090: instantiate gpio-tz1090-pdc metag: tz1090: select and instantiate gpio-tz1090 metag: tz1090: select and instantiate irq-imgpdc
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+* ImgTec Powerdown Controller (PDC) Interrupt Controller Binding
+
+This binding specifies what properties must be available in the device tree
+representation of a PDC IRQ controller. This has a number of input interrupt
+lines which can wake the system, and are passed on through output interrupt
+lines.
+
+Required properties:
+
+ - compatible: Specifies the compatibility list for the interrupt controller.
+ The type shall be <string> and the value shall include "img,pdc-intc".
+
+ - reg: Specifies the base PDC physical address(s) and size(s) of the
+ addressable register space. The type shall be <prop-encoded-array>.
+
+ - interrupt-controller: The presence of this property identifies the node
+ as an interrupt controller. No property value shall be defined.
+
+ - #interrupt-cells: Specifies the number of cells needed to encode an
+ interrupt source. The type shall be a <u32> and the value shall be 2.
+
+ - num-perips: Number of waking peripherals.
+
+ - num-syswakes: Number of SysWake inputs.
+
+ - interrupts: List of interrupt specifiers. The first specifier shall be the
+ shared SysWake interrupt, and remaining specifies shall be PDC peripheral
+ interrupts in order.
+
+* Interrupt Specifier Definition
+
+ Interrupt specifiers consists of 2 cells encoded as follows:
+
+ - <1st-cell>: The interrupt-number that identifies the interrupt source.
+ 0-7: Peripheral interrupts
+ 8-15: SysWake interrupts
+
+ - <2nd-cell>: The level-sense information, encoded using the Linux interrupt
+ flags as follows (only 4 valid for peripheral interrupts):
+ 0 = none (decided by software)
+ 1 = low-to-high edge triggered
+ 2 = high-to-low edge triggered
+ 3 = both edge triggered
+ 4 = active-high level-sensitive (required for perip irqs)
+ 8 = active-low level-sensitive
+
+* Examples
+
+Example 1:
+
+ /*
+ * TZ1090 PDC block
+ */
+ pdc: pdc@0x02006000 {
+ // This is an interrupt controller node.
+ interrupt-controller;
+
+ // Three cells to encode interrupt sources.
+ #interrupt-cells = <2>;
+
+ // Offset address of 0x02006000 and size of 0x1000.
+ reg = <0x02006000 0x1000>;
+
+ // Compatible with Meta hardware trigger block.
+ compatible = "img,pdc-intc";
+
+ // Three peripherals are connected.
+ num-perips = <3>;
+
+ // Four SysWakes are connected.
+ num-syswakes = <4>;
+
+ interrupts = <18 4 /* level */>, /* Syswakes */
+ <30 4 /* level */>, /* Peripheral 0 (RTC) */
+ <29 4 /* level */>, /* Peripheral 1 (IR) */
+ <31 4 /* level */>; /* Peripheral 2 (WDT) */
+ };
+
+Example 2:
+
+ /*
+ * An SoC peripheral that is wired through the PDC.
+ */
+ rtc0 {
+ // The interrupt controller that this device is wired to.
+ interrupt-parent = <&pdc>;
+
+ // Interrupt source Peripheral 0
+ interrupts = <0 /* Peripheral 0 (RTC) */
+ 4> /* IRQ_TYPE_LEVEL_HIGH */
+ };
+
+Example 3:
+
+ /*
+ * An interrupt generating device that is wired to a SysWake pin.
+ */
+ touchscreen0 {
+ // The interrupt controller that this device is wired to.
+ interrupt-parent = <&pdc>;
+
+ // Interrupt source SysWake 0 that is active-low level-sensitive
+ interrupts = <8 /* SysWake0 */
+ 8 /* IRQ_TYPE_LEVEL_LOW */>;
+ };