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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-18 12:58:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-18 12:58:39 -0700
commit2ec3240fd7956fe9525c336947b4473f7276f2b1 (patch)
tree11170bace173bd6eb88a57e08da3d46ee82a357a /Documentation/devicetree/bindings/gpio
parentf7df9be067160eef52f04bd2f137a20683fb1c12 (diff)
parent9910f5b199621aecfbdb0b63feb31ddd41fd63e2 (diff)
Merge tag 'armsoc-dt64' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM 64-bit DT updates from Arnd Bergmann: "We continue ramping up platform support for 64-bit ARM machines, with 111 individual non-merge changesets touching 21 platforms. The LG1312 platform is completely new and is the first ARM platform by LG that we support in the mainline kernel. Two other SoCs got added that are updated versions of existing SoC families, so the port mainly consists of new dts files: - The Hisilicon Hip06/D03 is the latest server platform from Huawei/Hisilicon, and follows the Hip05/D02 platform. - Rockchip RK3399 follows the 32-bit RK3288 that is popular in low-end Chromebooks and the 64-bit RK3368 that is mainly found in chinese Android TV boxes. The 96Boards HiKey based on the Hisilicon Hi6220 (Kirin 620) gets a long-awaited overhaul with a lot of devices enabled in the DT, so it should be much more usable with a mainline kernel now. See also https://plus.google.com/111524780435806926688/posts/PeGb2VsNhJd A lot of work went into enabling new device drivers on existing machines, but we also have a couple of new commercially available machines: - Google Pixel C laptop based on Tegra210 - Hardkernel Odroid C2 Based on Amlogic Meson GXBB (S905) - Geekbuying GeekBox based on Rockchip RK3368 And finally, a couple of reference or development platforms that are not end-user platforms but are used for trying out the respective SoC platforms: - Amlogic Meson GXBB P200 and P201 development systems - NXP Layerscape 1043A QDS development board - Hisilicon Hip06 D03 server board, as mentioned above - LG1312 Reference Design - RK3399 Evaluation Board" * tag 'armsoc-dt64' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (104 commits) arm64: dts: marvell: add XOR node for Armada 3700 SoC dt-bindings: document rockchip rk3399-evb board arm64: dts: rockchip: add dts file for RK3399 evaluation board arm64: dts: rockchip: add core dtsi file for RK3399 SoCs dt-bindings: rockchip-dw-mshc: add description for rk3399 arm64: dts: marvell: Use a SoC-specific compatible for xHCI on Armada37xx arm64: dts: marvell: Rename armada-37xx USB node arm64: dts: marvell: Clean up armada-3720-db Documentation: arm64: Add Hisilicon Hip06 D03 dts binding arm64: dts: Add initial dts for Hisilicon Hip06 D03 board arm64: dts: hip05: Add nor flash support arm64: dts: hip05: fix its node without msi-cells arm64: dts: r8a7795: Don't disable referenced optional clocks arm64: dts: salvator-x: populate EXTALR arm64: dts: r8a7795: enable PCIe on Salvator-X arm64: dts: r8a7795: Add PCIe nodes arm64: tegra: Add IOMMU node to GM20B on Tegra210 arm64: tegra: Add reference clock to GM20B on Tegra210 dt-bindings: Add documentation for GM20B GPU dt-bindings: gk20a: Document iommus property ...
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diff --git a/Documentation/devicetree/bindings/gpio/nvidia,tegra186-gpio.txt b/Documentation/devicetree/bindings/gpio/nvidia,tegra186-gpio.txt
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+NVIDIA Tegra186 GPIO controllers
+
+Tegra186 contains two GPIO controllers; a main controller and an "AON"
+controller. This binding document applies to both controllers. The register
+layouts for the controllers share many similarities, but also some significant
+differences. Hence, this document describes closely related but different
+bindings and compatible values.
+
+The Tegra186 GPIO controller allows software to set the IO direction of, and
+read/write the value of, numerous GPIO signals. Routing of GPIO signals to
+package balls is under the control of a separate pin controller HW block. Two
+major sets of registers exist:
+
+a) Security registers, which allow configuration of allowed access to the GPIO
+register set. These registers exist in a single contiguous block of physical
+address space. The size of this block, and the security features available,
+varies between the different GPIO controllers.
+
+Access to this set of registers is not necessary in all circumstances. Code
+that wishes to configure access to the GPIO registers needs access to these
+registers to do so. Code which simply wishes to read or write GPIO data does not
+need access to these registers.
+
+b) GPIO registers, which allow manipulation of the GPIO signals. In some GPIO
+controllers, these registers are exposed via multiple "physical aliases" in
+address space, each of which access the same underlying state. See the hardware
+documentation for rationale. Any particular GPIO client is expected to access
+just one of these physical aliases.
+
+Tegra HW documentation describes a unified naming convention for all GPIOs
+implemented by the SoC. Each GPIO is assigned to a port, and a port may control
+a number of GPIOs. Thus, each GPIO is named according to an alphabetical port
+name and an integer GPIO name within the port. For example, GPIO_PA0, GPIO_PN6,
+or GPIO_PCC3.
+
+The number of ports implemented by each GPIO controller varies. The number of
+implemented GPIOs within each port varies. GPIO registers within a controller
+are grouped and laid out according to the port they affect.
+
+The mapping from port name to the GPIO controller that implements that port, and
+the mapping from port name to register offset within a controller, are both
+extremely non-linear. The header file <dt-bindings/gpio/tegra186-gpio.h>
+describes the port-level mapping. In that file, the naming convention for ports
+matches the HW documentation. The values chosen for the names are alphabetically
+sorted within a particular controller. Drivers need to map between the DT GPIO
+IDs and HW register offsets using a lookup table.
+
+Each GPIO controller can generate a number of interrupt signals. Each signal
+represents the aggregate status for all GPIOs within a set of ports. Thus, the
+number of interrupt signals generated by a controller varies as a rough function
+of the number of ports it implements. Note that the HW documentation refers to
+both the overall controller HW module and the sets-of-ports as "controllers".
+
+Each GPIO controller in fact generates multiple interrupts signals for each set
+of ports. Each GPIO may be configured to feed into a specific one of the
+interrupt signals generated by a set-of-ports. The intent is for each generated
+signal to be routed to a different CPU, thus allowing different CPUs to each
+handle subsets of the interrupts within a port. The status of each of these
+per-port-set signals is reported via a separate register. Thus, a driver needs
+to know which status register to observe. This binding currently defines no
+configuration mechanism for this. By default, drivers should use register
+GPIO_${port}_INTERRUPT_STATUS_G1_0. Future revisions to the binding could
+define a property to configure this.
+
+Required properties:
+- compatible
+ Array of strings.
+ One of:
+ - "nvidia,tegra186-gpio".
+ - "nvidia,tegra186-gpio-aon".
+- reg-names
+ Array of strings.
+ Contains a list of names for the register spaces described by the reg
+ property. May contain the following entries, in any order:
+ - "gpio": Mandatory. GPIO control registers. This may cover either:
+ a) The single physical alias that this OS should use.
+ b) All physical aliases that exist in the controller. This is
+ appropriate when the OS is responsible for managing assignment of
+ the physical aliases.
+ - "security": Optional. Security configuration registers.
+ Users of this binding MUST look up entries in the reg property by name,
+ using this reg-names property to do so.
+- reg
+ Array of (physical base address, length) tuples.
+ Must contain one entry per entry in the reg-names property, in a matching
+ order.
+- interrupts
+ Array of interrupt specifiers.
+ The interrupt outputs from the HW block, one per set of ports, in the
+ order the HW manual describes them. The number of entries required varies
+ depending on compatible value:
+ - "nvidia,tegra186-gpio": 6 entries.
+ - "nvidia,tegra186-gpio-aon": 1 entry.
+- gpio-controller
+ Boolean.
+ Marks the device node as a GPIO controller/provider.
+- #gpio-cells
+ Single-cell integer.
+ Must be <2>.
+ Indicates how many cells are used in a consumer's GPIO specifier.
+ In the specifier:
+ - The first cell is the pin number.
+ See <dt-bindings/gpio/tegra186-gpio.h>.
+ - The second cell contains flags:
+ - Bit 0 specifies polarity
+ - 0: Active-high (normal).
+ - 1: Active-low (inverted).
+- interrupt-controller
+ Boolean.
+ Marks the device node as an interrupt controller/provider.
+- #interrupt-cells
+ Single-cell integer.
+ Must be <2>.
+ Indicates how many cells are used in a consumer's interrupt specifier.
+ In the specifier:
+ - The first cell is the GPIO number.
+ See <dt-bindings/gpio/tegra186-gpio.h>.
+ - The second cell is contains flags:
+ - Bits [3:0] indicate trigger type and level:
+ - 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.
+
+Example:
+
+#include <dt-bindings/interrupt-controller/irq.h>
+
+gpio@2200000 {
+ compatible = "nvidia,tegra186-gpio";
+ reg-names = "security", "gpio";
+ reg =
+ <0x0 0x2200000 0x0 0x10000>,
+ <0x0 0x2210000 0x0 0x10000>;
+ interrupts =
+ <0 47 IRQ_TYPE_LEVEL_HIGH>,
+ <0 50 IRQ_TYPE_LEVEL_HIGH>,
+ <0 53 IRQ_TYPE_LEVEL_HIGH>,
+ <0 56 IRQ_TYPE_LEVEL_HIGH>,
+ <0 59 IRQ_TYPE_LEVEL_HIGH>,
+ <0 180 IRQ_TYPE_LEVEL_HIGH>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+};
+
+gpio@c2f0000 {
+ compatible = "nvidia,tegra186-gpio-aon";
+ reg-names = "security", "gpio";
+ reg =
+ <0x0 0xc2f0000 0x0 0x1000>,
+ <0x0 0xc2f1000 0x0 0x1000>;
+ interrupts =
+ <0 60 IRQ_TYPE_LEVEL_HIGH>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+};