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authorDave Airlie <airlied@redhat.com>2011-03-14 07:15:13 +0300
committerDave Airlie <airlied@redhat.com>2011-03-14 07:15:13 +0300
commit34db18abd376b2075c760c38f0b861aed379415d (patch)
treec4174e39a2f445f17c25ab206d45c66217bbbf85 /Documentation/devicetree/bindings/gpio/gpio.txt
parente73f88af66fcc50083fae4b7e1c39b469179a97a (diff)
parent47ae63e0c2e5fdb582d471dc906eb29be94c732f (diff)
downloadlinux-34db18abd376b2075c760c38f0b861aed379415d.tar.xz
Merge remote branch 'intel/drm-intel-next' of ../drm-next into drm-core-next
* 'intel/drm-intel-next' of ../drm-next: (755 commits) drm/i915: Only wait on a pending flip if we intend to write to the buffer drm/i915/dp: Sanity check eDP existence drm/i915: Rebind the buffer if its alignment constraints changes with tiling drm/i915: Disable GPU semaphores by default drm/i915: Do not overflow the MMADDR write FIFO Revert "drm/i915: fix corruptions on i8xx due to relaxed fencing" drm/i915: Don't save/restore hardware status page address register drm/i915: don't store the reg value for HWS_PGA drm/i915: fix memory corruption with GM965 and >4GB RAM Linux 2.6.38-rc7 Revert "TPM: Long default timeout fix" drm/i915: Re-enable GPU semaphores for SandyBridge mobile drm/i915: Replace vblank PM QoS with "Interrupt-Based AGPBUSY#" Revert "drm/i915: Use PM QoS to prevent C-State starvation of gen3 GPU" drm/i915: Allow relocation deltas outside of target bo drm/i915: Silence an innocuous compiler warning for an unused variable fs/block_dev.c: fix new kernel-doc warning ACPI: Fix build for CONFIG_NET unset mm: <asm-generic/pgtable.h> must include <linux/mm_types.h> x86: Use u32 instead of long to set reset vector back to 0 ... Conflicts: drivers/gpu/drm/i915/i915_gem.c
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diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
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+Specifying GPIO information for devices
+============================================
+
+1) gpios property
+-----------------
+
+Nodes that makes use of GPIOs should define them using `gpios' property,
+format of which is: <&gpio-controller1-phandle gpio1-specifier
+ &gpio-controller2-phandle gpio2-specifier
+ 0 /* holes are permitted, means no GPIO 3 */
+ &gpio-controller4-phandle gpio4-specifier
+ ...>;
+
+Note that gpio-specifier length is controller dependent.
+
+gpio-specifier may encode: bank, pin position inside the bank,
+whether pin is open-drain and whether pin is logically inverted.
+
+Example of the node using GPIOs:
+
+ node {
+ gpios = <&qe_pio_e 18 0>;
+ };
+
+In this example gpio-specifier is "18 0" and encodes GPIO pin number,
+and empty GPIO flags as accepted by the "qe_pio_e" gpio-controller.
+
+2) gpio-controller nodes
+------------------------
+
+Every GPIO controller node must have #gpio-cells property defined,
+this information will be used to translate gpio-specifiers.
+
+Example of two SOC GPIO banks defined as gpio-controller nodes:
+
+ qe_pio_a: gpio-controller@1400 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank";
+ reg = <0x1400 0x18>;
+ gpio-controller;
+ };
+
+ qe_pio_e: gpio-controller@1460 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
+ reg = <0x1460 0x18>;
+ gpio-controller;
+ };
+
+