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Merge tag 'tegra-for-4.7-gpio' of git://git.kernel.org/pub/scm/linux/…
…kernel/git/tegra/linux into next/dt64 Merge "dt-bindings: gpio: tegra: Add Tegra186 support" from Thierry Reding: Adds device tree bindings for the GPIO and AON controllers found on the Tegra186 SoC. * tag 'tegra-for-4.7-gpio' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux: ARM: tegra: Add DT binding for Tegra186 GPIO controllers ARM: tegra: Fix naming in GPIO DT binding header
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Documentation/devicetree/bindings/gpio/nvidia,tegra186-gpio.txt
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NVIDIA Tegra186 GPIO controllers | ||
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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. | ||
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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: | ||
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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. | ||
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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. | ||
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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. | ||
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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. | ||
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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. | ||
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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. | ||
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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". | ||
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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. | ||
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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. | ||
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Example: | ||
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#include <dt-bindings/interrupt-controller/irq.h> | ||
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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>; | ||
}; | ||
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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>; | ||
}; |
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/* | ||
* This header provides constants for binding nvidia,tegra186-gpio*. | ||
* | ||
* The first cell in Tegra's GPIO specifier is the GPIO ID. The macros below | ||
* provide names for this. | ||
* | ||
* The second cell contains standard flag values specified in gpio.h. | ||
*/ | ||
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#ifndef _DT_BINDINGS_GPIO_TEGRA_GPIO_H | ||
#define _DT_BINDINGS_GPIO_TEGRA_GPIO_H | ||
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#include <dt-bindings/gpio/gpio.h> | ||
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/* GPIOs implemented by main GPIO controller */ | ||
#define TEGRA_MAIN_GPIO_PORT_A 0 | ||
#define TEGRA_MAIN_GPIO_PORT_B 1 | ||
#define TEGRA_MAIN_GPIO_PORT_C 2 | ||
#define TEGRA_MAIN_GPIO_PORT_D 3 | ||
#define TEGRA_MAIN_GPIO_PORT_E 4 | ||
#define TEGRA_MAIN_GPIO_PORT_F 5 | ||
#define TEGRA_MAIN_GPIO_PORT_G 6 | ||
#define TEGRA_MAIN_GPIO_PORT_H 7 | ||
#define TEGRA_MAIN_GPIO_PORT_I 8 | ||
#define TEGRA_MAIN_GPIO_PORT_J 9 | ||
#define TEGRA_MAIN_GPIO_PORT_K 10 | ||
#define TEGRA_MAIN_GPIO_PORT_L 11 | ||
#define TEGRA_MAIN_GPIO_PORT_M 12 | ||
#define TEGRA_MAIN_GPIO_PORT_N 13 | ||
#define TEGRA_MAIN_GPIO_PORT_O 14 | ||
#define TEGRA_MAIN_GPIO_PORT_P 15 | ||
#define TEGRA_MAIN_GPIO_PORT_Q 16 | ||
#define TEGRA_MAIN_GPIO_PORT_R 17 | ||
#define TEGRA_MAIN_GPIO_PORT_T 18 | ||
#define TEGRA_MAIN_GPIO_PORT_X 19 | ||
#define TEGRA_MAIN_GPIO_PORT_Y 20 | ||
#define TEGRA_MAIN_GPIO_PORT_BB 21 | ||
#define TEGRA_MAIN_GPIO_PORT_CC 22 | ||
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#define TEGRA_MAIN_GPIO(port, offset) \ | ||
((TEGRA_MAIN_GPIO_PORT_##port * 8) + offset) | ||
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/* GPIOs implemented by AON GPIO controller */ | ||
#define TEGRA_AON_GPIO_PORT_S 0 | ||
#define TEGRA_AON_GPIO_PORT_U 1 | ||
#define TEGRA_AON_GPIO_PORT_V 2 | ||
#define TEGRA_AON_GPIO_PORT_W 3 | ||
#define TEGRA_AON_GPIO_PORT_Z 4 | ||
#define TEGRA_AON_GPIO_PORT_AA 5 | ||
#define TEGRA_AON_GPIO_PORT_EE 6 | ||
#define TEGRA_AON_GPIO_PORT_FF 7 | ||
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#define TEGRA_AON_GPIO(port, offset) \ | ||
((TEGRA_AON_GPIO_PORT_##port * 8) + offset) | ||
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#endif |