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-rw-r--r--Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt2
-rw-r--r--Documentation/devicetree/bindings/pinctrl/ingenic,pinctrl.txt41
-rw-r--r--Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt25
-rw-r--r--Documentation/devicetree/bindings/pinctrl/pinctrl-zx.txt85
-rw-r--r--Documentation/devicetree/bindings/pinctrl/qcom,ipq8074-pinctrl.txt172
-rw-r--r--Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt2
-rw-r--r--Documentation/devicetree/bindings/pinctrl/renesas,rza1-pinctrl.txt221
7 files changed, 539 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
index b53224473672..6f2ec9af0de2 100644
--- a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
@@ -20,8 +20,10 @@ Required properties:
"allwinner,sun9i-a80-pinctrl"
"allwinner,sun9i-a80-r-pinctrl"
"allwinner,sun8i-a83t-pinctrl"
+ "allwinner,sun8i-a83t-r-pinctrl"
"allwinner,sun8i-h3-pinctrl"
"allwinner,sun8i-h3-r-pinctrl"
+ "allwinner,sun8i-r40-pinctrl"
"allwinner,sun50i-a64-pinctrl"
"allwinner,sun50i-a64-r-pinctrl"
"allwinner,sun50i-h5-pinctrl"
diff --git a/Documentation/devicetree/bindings/pinctrl/ingenic,pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/ingenic,pinctrl.txt
new file mode 100644
index 000000000000..ca313a7aeaff
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/ingenic,pinctrl.txt
@@ -0,0 +1,41 @@
+Ingenic jz47xx pin controller
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+For the jz47xx SoCs, pin control is tightly bound with GPIO ports. All pins may
+be used as GPIOs, multiplexed device functions are configured within the
+GPIO port configuration registers and it is typical to refer to pins using the
+naming scheme "PxN" where x is a character identifying the GPIO port with
+which the pin is associated and N is an integer from 0 to 31 identifying the
+pin within that GPIO port. For example PA0 is the first pin in GPIO port A, and
+PB31 is the last pin in GPIO port B. The jz4740 contains 4 GPIO ports, PA to
+PD, for a total of 128 pins. The jz4780 contains 6 GPIO ports, PA to PF, for a
+total of 192 pins.
+
+
+Required properties:
+--------------------
+
+ - compatible: One of:
+ - "ingenic,jz4740-pinctrl"
+ - "ingenic,jz4770-pinctrl"
+ - "ingenic,jz4780-pinctrl"
+ - reg: Address range of the pinctrl registers.
+
+
+GPIO sub-nodes
+--------------
+
+The pinctrl node can have optional sub-nodes for the Ingenic GPIO driver;
+please refer to ../gpio/ingenic,gpio.txt.
+
+
+Example:
+--------
+
+pinctrl: pin-controller@10010000 {
+ compatible = "ingenic,jz4740-pinctrl";
+ reg = <0x10010000 0x400>;
+};
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
index f01d154090da..62d0f33fa65e 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
@@ -204,21 +204,22 @@ each single pin the number of required sub-nodes containing "pin" and
maintain.
For cases like this, the pin controller driver may use the pinmux helper
-property, where the pin identifier is packed with mux configuration settings
-in a single integer.
+property, where the pin identifier is provided with mux configuration settings
+in a pinmux group. A pinmux group consists of the pin identifier and mux
+settings represented as a single integer or an array of integers.
-The pinmux property accepts an array of integers, each of them describing
+The pinmux property accepts an array of pinmux groups, each of them describing
a single pin multiplexing configuration.
pincontroller {
state_0_node_a {
- pinmux = <PIN_ID_AND_MUX>, <PIN_ID_AND_MUX>, ...;
+ pinmux = <PINMUX_GROUP>, <PINMUX_GROUP>, ...;
};
};
Each individual pin controller driver bindings documentation shall specify
-how those values (pin IDs and pin multiplexing configuration) are defined and
-assembled together.
+how pin IDs and pin multiplexing configuration are defined and assembled
+together in a pinmux group.
== Generic pin configuration node content ==
@@ -251,14 +252,20 @@ drive-push-pull - drive actively high and low
drive-open-drain - drive with open drain
drive-open-source - drive with open source
drive-strength - sink or source at most X mA
-input-enable - enable input on pin (no effect on output)
-input-disable - disable input on pin (no effect on output)
+input-enable - enable input on pin (no effect on output, such as
+ enabling an input buffer)
+input-disable - disable input on pin (no effect on output, such as
+ disabling an input buffer)
input-schmitt-enable - enable schmitt-trigger mode
input-schmitt-disable - disable schmitt-trigger mode
input-debounce - debounce mode with debound time X
power-source - select between different power supplies
low-power-enable - enable low power mode
low-power-disable - disable low power mode
+output-disable - disable output on a pin (such as disable an output
+ buffer)
+output-enable - enable output on a pin without actively driving it
+ (such as enabling an output buffer)
output-low - set the pin to output mode with low level
output-high - set the pin to output mode with high level
slew-rate - set the slew rate
@@ -300,7 +307,7 @@ arguments are described below.
- pinmux takes a list of pin IDs and mux settings as required argument. The
specific bindings for the hardware defines:
- How pin IDs and mux settings are defined and assembled together in a single
- integer.
+ integer or an array of integers.
- bias-pull-up, -down and -pin-default take as optional argument on hardware
supporting it the pull strength in Ohm. bias-disable will disable the pull.
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-zx.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-zx.txt
new file mode 100644
index 000000000000..e219849b21ca
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-zx.txt
@@ -0,0 +1,85 @@
+* ZTE ZX Pin Controller
+
+The pin controller on ZTE ZX platforms is kinda of hybrid. It consists of
+a main controller and an auxiliary one. For example, on ZX296718 SoC, the
+main controller is TOP_PMM and the auxiliary one is AON_IOCFG. Both
+controllers work together to control pin multiplexing and configuration in
+the way illustrated as below.
+
+
+ GMII_RXD3 ---+
+ |
+ DVI1_HS ---+----------------------------- GMII_RXD3 (TOP pin)
+ |
+ BGPIO16 ---+ ^
+ | pinconf
+ ^ |
+ | pinmux |
+ | |
+
+ TOP_PMM (main) AON_IOCFG (aux)
+
+ | | |
+ | pinmux | |
+ | pinmux v |
+ v | pinconf
+ KEY_ROW2 ---+ v
+ PORT1_LCD_TE ---+ |
+ | AGPIO10 ---+------ KEY_ROW2 (AON pin)
+ I2S0_DOUT3 ---+ |
+ |-----------------------+
+ PWM_OUT3 ---+
+ |
+ VGA_VS1 ---+
+
+
+For most of pins like GMII_RXD3 in the figure, the pinmux function is
+controlled by TOP_PMM block only, and this type of pins are meant by term
+'TOP pins'. For pins like KEY_ROW2, the pinmux is controlled by both
+TOP_PMM and AON_IOCFG blocks, as the available multiplexing functions for
+the pin spread in both controllers. This type of pins are called 'AON pins'.
+Though pinmux implementation is quite different, pinconf is same for both
+types of pins. Both are controlled by auxiliary controller, i.e. AON_IOCFG
+on ZX296718.
+
+Required properties:
+- compatible: should be "zte,zx296718-pmm".
+- reg: the register physical address and length.
+- zte,auxiliary-controller: phandle to the auxiliary pin controller which
+ implements pinmux for AON pins and pinconf for all pins.
+
+The following pin configuration are supported. Please refer to
+pinctrl-bindings.txt in this directory for more details of the common
+pinctrl bindings used by client devices.
+
+- bias-pull-up
+- bias-pull-down
+- drive-strength
+- input-enable
+- slew-rate
+
+Examples:
+
+iocfg: pin-controller@119000 {
+ compatible = "zte,zx296718-iocfg";
+ reg = <0x119000 0x1000>;
+};
+
+pmm: pin-controller@1462000 {
+ compatible = "zte,zx296718-pmm";
+ reg = <0x1462000 0x1000>;
+ zte,auxiliary-controller = <&iocfg>;
+};
+
+&pmm {
+ vga_pins: vga {
+ pins = "KEY_COL1", "KEY_COL2", "KEY_ROW1", "KEY_ROW2";
+ function = "VGA";
+ };
+};
+
+&vga {
+ pinctrl-names = "default";
+ pinctrl-0 = <&vga_pins>;
+ status = "okay";
+};
diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,ipq8074-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,ipq8074-pinctrl.txt
new file mode 100644
index 000000000000..407b9443629d
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,ipq8074-pinctrl.txt
@@ -0,0 +1,172 @@
+Qualcomm Technologies, Inc. IPQ8074 TLMM block
+
+This binding describes the Top Level Mode Multiplexer block found in the
+IPQ8074 platform.
+
+- compatible:
+ Usage: required
+ Value type: <string>
+ Definition: must be "qcom,ipq8074-pinctrl"
+
+- reg:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: the base address and size of the TLMM register space.
+
+- interrupts:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: should specify the TLMM summary IRQ.
+
+- interrupt-controller:
+ Usage: required
+ Value type: <none>
+ Definition: identifies this node as an interrupt controller
+
+- #interrupt-cells:
+ Usage: required
+ Value type: <u32>
+ Definition: must be 2. Specifying the pin number and flags, as defined
+ in <dt-bindings/interrupt-controller/irq.h>
+
+- gpio-controller:
+ Usage: required
+ Value type: <none>
+ Definition: identifies this node as a gpio controller
+
+- #gpio-cells:
+ Usage: required
+ Value type: <u32>
+ Definition: must be 2. Specifying the pin number and flags, as defined
+ in <dt-bindings/gpio/gpio.h>
+
+Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
+a general description of GPIO and interrupt bindings.
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+The pin configuration nodes act as a container for an arbitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+pin, a group, or a list of pins or groups. This configuration can include the
+mux function to select on those pin(s)/group(s), and various pin configuration
+parameters, such as pull-up, drive strength, etc.
+
+
+PIN CONFIGURATION NODES:
+
+The name of each subnode is not important; all subnodes should be enumerated
+and processed purely based on their content.
+
+Each subnode only affects those parameters that are explicitly listed. In
+other words, a subnode that lists a mux function but no pin configuration
+parameters implies no information about any pin configuration parameters.
+Similarly, a pin subnode that describes a pullup parameter implies no
+information about e.g. the mux function.
+
+
+The following generic properties as defined in pinctrl-bindings.txt are valid
+to specify in a pin configuration subnode:
+
+- pins:
+ Usage: required
+ Value type: <string-array>
+ Definition: List of gpio pins affected by the properties specified in
+ this subnode. Valid pins are:
+ gpio0-gpio69
+
+- function:
+ Usage: required
+ Value type: <string>
+ Definition: Specify the alternative function to be configured for the
+ specified pins. Functions are only valid for gpio pins.
+ Valid values are:
+ atest_char, atest_char0, atest_char1, atest_char2,
+ atest_char3, audio_rxbclk, audio_rxd, audio_rxfsync,
+ audio_rxmclk, audio_txbclk, audio_txd, audio_txfsync,
+ audio_txmclk, blsp0_i2c, blsp0_spi, blsp0_uart, blsp1_i2c,
+ blsp1_spi, blsp1_uart, blsp2_i2c, blsp2_spi, blsp2_uart,
+ blsp3_i2c, blsp3_spi, blsp3_spi0, blsp3_spi1, blsp3_spi2,
+ blsp3_spi3, blsp3_uart, blsp4_i2c0, blsp4_i2c1, blsp4_spi0,
+ blsp4_spi1, blsp4_uart0, blsp4_uart1, blsp5_i2c, blsp5_spi,
+ blsp5_uart, burn0, burn1, cri_trng, cri_trng0, cri_trng1,
+ cxc0, cxc1, dbg_out, gcc_plltest, gcc_tlmm, gpio, ldo_en,
+ ldo_update, led0, led1, led2, mac0_sa0, mac0_sa1, mac1_sa0,
+ mac1_sa1, mac1_sa2, mac1_sa3, mac2_sa0, mac2_sa1, mdc,
+ mdio, pcie0_clk, pcie0_rst, pcie0_wake, pcie1_clk,
+ pcie1_rst, pcie1_wake, pcm_drx, pcm_dtx, pcm_fsync,
+ pcm_pclk, pcm_zsi0, pcm_zsi1, prng_rosc, pta1_0, pta1_1,
+ pta1_2, pta2_0, pta2_1, pta2_2, pwm0, pwm1, pwm2, pwm3,
+ qdss_cti_trig_in_a0, qdss_cti_trig_in_a1,
+ qdss_cti_trig_in_b0, qdss_cti_trig_in_b1,
+ qdss_cti_trig_out_a0, qdss_cti_trig_out_a1,
+ qdss_cti_trig_out_b0, qdss_cti_trig_out_b1,
+ qdss_traceclk_a, qdss_traceclk_b, qdss_tracectl_a,
+ qdss_tracectl_b, qdss_tracedata_a, qdss_tracedata_b,
+ qpic, rx0, rx1, rx2, sd_card, sd_write, tsens_max, wci2a,
+ wci2b, wci2c, wci2d
+
+- bias-disable:
+ Usage: optional
+ Value type: <none>
+ Definition: The specified pins should be configued as no pull.
+
+- bias-pull-down:
+ Usage: optional
+ Value type: <none>
+ Definition: The specified pins should be configued as pull down.
+
+- bias-pull-up:
+ Usage: optional
+ Value type: <none>
+ Definition: The specified pins should be configued as pull up.
+
+- output-high:
+ Usage: optional
+ Value type: <none>
+ Definition: The specified pins are configured in output mode, driven
+ high.
+
+- output-low:
+ Usage: optional
+ Value type: <none>
+ Definition: The specified pins are configured in output mode, driven
+ low.
+
+- drive-strength:
+ Usage: optional
+ Value type: <u32>
+ Definition: Selects the drive strength for the specified pins, in mA.
+ Valid values are: 2, 4, 6, 8, 10, 12, 14 and 16
+
+Example:
+
+ tlmm: pinctrl@1000000 {
+ compatible = "qcom,ipq8074-pinctrl";
+ reg = <0x1000000 0x300000>;
+ interrupts = <GIC_SPI 208 IRQ_TYPE_LEVEL_HIGH>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+
+ uart2: uart2-default {
+ mux {
+ pins = "gpio23", "gpio24";
+ function = "blsp4_uart1";
+ };
+
+ rx {
+ pins = "gpio23";
+ drive-strength = <4>;
+ bias-disable;
+ };
+
+ tx {
+ pins = "gpio24";
+ drive-strength = <2>;
+ bias-pull-up;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
index 13df9498311a..645082f03259 100644
--- a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
@@ -13,6 +13,8 @@ Required Properties:
- "renesas,pfc-emev2": for EMEV2 (EMMA Mobile EV2) compatible pin-controller.
- "renesas,pfc-r8a73a4": for R8A73A4 (R-Mobile APE6) compatible pin-controller.
- "renesas,pfc-r8a7740": for R8A7740 (R-Mobile A1) compatible pin-controller.
+ - "renesas,pfc-r8a7743": for R8A7743 (RZ/G1M) compatible pin-controller.
+ - "renesas,pfc-r8a7745": for R8A7745 (RZ/G1E) compatible pin-controller.
- "renesas,pfc-r8a7778": for R8A7778 (R-Mobile M1) compatible pin-controller.
- "renesas,pfc-r8a7779": for R8A7779 (R-Car H1) compatible pin-controller.
- "renesas,pfc-r8a7790": for R8A7790 (R-Car H2) compatible pin-controller.
diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,rza1-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/renesas,rza1-pinctrl.txt
new file mode 100644
index 000000000000..43e21474528a
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/renesas,rza1-pinctrl.txt
@@ -0,0 +1,221 @@
+Renesas RZ/A1 combined Pin and GPIO controller
+
+The Renesas SoCs of the RZ/A1 family feature a combined Pin and GPIO controller,
+named "Ports" in the hardware reference manual.
+Pin multiplexing and GPIO configuration is performed on a per-pin basis
+writing configuration values to per-port register sets.
+Each "port" features up to 16 pins, each of them configurable for GPIO
+function (port mode) or in alternate function mode.
+Up to 8 different alternate function modes exist for each single pin.
+
+Pin controller node
+-------------------
+
+Required properties:
+ - compatible
+ this shall be "renesas,r7s72100-ports".
+
+ - reg
+ address base and length of the memory area where the pin controller
+ hardware is mapped to.
+
+Example:
+Pin controller node for RZ/A1H SoC (r7s72100)
+
+pinctrl: pin-controller@fcfe3000 {
+ compatible = "renesas,r7s72100-ports";
+
+ reg = <0xfcfe3000 0x4230>;
+};
+
+Sub-nodes
+---------
+
+The child nodes of the pin controller node describe a pin multiplexing
+function or a GPIO controller alternatively.
+
+- Pin multiplexing sub-nodes:
+ A pin multiplexing sub-node describes how to configure a set of
+ (or a single) pin in some desired alternate function mode.
+ A single sub-node may define several pin configurations.
+ A few alternate function require special pin configuration flags to be
+ supplied along with the alternate function configuration number.
+ The hardware reference manual specifies when a pin function requires
+ "software IO driven" mode to be specified. To do so use the generic
+ properties from the <include/linux/pinctrl/pinconf_generic.h> header file
+ to instruct the pin controller to perform the desired pin configuration
+ operation.
+ Please refer to pinctrl-bindings.txt to get to know more on generic
+ pin properties usage.
+
+ The allowed generic formats for a pin multiplexing sub-node are the
+ following ones:
+
+ node-1 {
+ pinmux = <PIN_ID_AND_MUX>, <PIN_ID_AND_MUX>, ... ;
+ GENERIC_PINCONFIG;
+ };
+
+ node-2 {
+ sub-node-1 {
+ pinmux = <PIN_ID_AND_MUX>, <PIN_ID_AND_MUX>, ... ;
+ GENERIC_PINCONFIG;
+ };
+
+ sub-node-2 {
+ pinmux = <PIN_ID_AND_MUX>, <PIN_ID_AND_MUX>, ... ;
+ GENERIC_PINCONFIG;
+ };
+
+ ...
+
+ sub-node-n {
+ pinmux = <PIN_ID_AND_MUX>, <PIN_ID_AND_MUX>, ... ;
+ GENERIC_PINCONFIG;
+ };
+ };
+
+ Use the second format when pins part of the same logical group need to have
+ different generic pin configuration flags applied.
+
+ Client sub-nodes shall refer to pin multiplexing sub-nodes using the phandle
+ of the most external one.
+
+ Eg.
+
+ client-1 {
+ ...
+ pinctrl-0 = <&node-1>;
+ ...
+ };
+
+ client-2 {
+ ...
+ pinctrl-0 = <&node-2>;
+ ...
+ };
+
+ Required properties:
+ - pinmux:
+ integer array representing pin number and pin multiplexing configuration.
+ When a pin has to be configured in alternate function mode, use this
+ property to identify the pin by its global index, and provide its
+ alternate function configuration number along with it.
+ When multiple pins are required to be configured as part of the same
+ alternate function they shall be specified as members of the same
+ argument list of a single "pinmux" property.
+ Helper macros to ease assembling the pin index from its position
+ (port where it sits on and pin number) and alternate function identifier
+ are provided by the pin controller header file at:
+ <include/dt-bindings/pinctrl/r7s72100-pinctrl.h>
+ Integers values in "pinmux" argument list are assembled as:
+ ((PORT * 16 + PIN) | MUX_FUNC << 16)
+
+ Optional generic properties:
+ - input-enable:
+ enable input bufer for pins requiring software driven IO input
+ operations.
+ - output-high:
+ enable output buffer for pins requiring software driven IO output
+ operations. output-low can be used alternatively, as line value is
+ ignored by the driver.
+
+ The hardware reference manual specifies when a pin has to be configured to
+ work in bi-directional mode and when the IO direction has to be specified
+ by software. Bi-directional pins are managed by the pin controller driver
+ internally, while software driven IO direction has to be explicitly
+ selected when multiple options are available.
+
+ Example:
+ A serial communication interface with a TX output pin and an RX input pin.
+
+ &pinctrl {
+ scif2_pins: serial2 {
+ pinmux = <RZA1_PINMUX(3, 0, 6)>, <RZA1_PINMUX(3, 2, 4)>;
+ };
+ };
+
+ Pin #0 on port #3 is configured as alternate function #6.
+ Pin #2 on port #3 is configured as alternate function #4.
+
+ Example 2:
+ I2c master: both SDA and SCL pins need bi-directional operations
+
+ &pinctrl {
+ i2c2_pins: i2c2 {
+ pinmux = <RZA1_PINMUX(1, 4, 1)>, <RZA1_PINMUX(1, 5, 1)>;
+ };
+ };
+
+ Pin #4 on port #1 is configured as alternate function #1.
+ Pin #5 on port #1 is configured as alternate function #1.
+ Both need to work in bi-directional mode, the driver manages this internally.
+
+ Example 3:
+ Multi-function timer input and output compare pins.
+ Configure TIOC0A as software driven input and TIOC0B as software driven
+ output.
+
+ &pinctrl {
+ tioc0_pins: tioc0 {
+ tioc0_input_pins {
+ pinumx = <RZA1_PINMUX(4, 0, 2)>;
+ input-enable;
+ };
+
+ tioc0_output_pins {
+ pinmux = <RZA1_PINMUX(4, 1, 1)>;
+ output-enable;
+ };
+ };
+ };
+
+ &tioc0 {
+ ...
+ pinctrl-0 = <&tioc0_pins>;
+ ...
+ };
+
+ Pin #0 on port #4 is configured as alternate function #2 with IO direction
+ specified by software as input.
+ Pin #1 on port #4 is configured as alternate function #1 with IO direction
+ specified by software as output.
+
+- GPIO controller sub-nodes:
+ Each port of the r7s72100 pin controller hardware is itself a GPIO controller.
+ Different SoCs have different numbers of available pins per port, but
+ generally speaking, each of them can be configured in GPIO ("port") mode
+ on this hardware.
+ Describe GPIO controllers using sub-nodes with the following properties.
+
+ Required properties:
+ - gpio-controller
+ empty property as defined by the GPIO bindings documentation.
+ - #gpio-cells
+ number of cells required to identify and configure a GPIO.
+ Shall be 2.
+ - gpio-ranges
+ Describes a GPIO controller specifying its specific pin base, the pin
+ base in the global pin numbering space, and the number of controlled
+ pins, as defined by the GPIO bindings documentation. Refer to
+ Documentation/devicetree/bindings/gpio/gpio.txt file for a more detailed
+ description.
+
+ Example:
+ A GPIO controller node, controlling 16 pins indexed from 0.
+ The GPIO controller base in the global pin indexing space is pin 48, thus
+ pins [0 - 15] on this controller map to pins [48 - 63] in the global pin
+ indexing space.
+
+ port3: gpio-3 {
+ gpio-controller;
+ #gpio-cells = <2>;
+ gpio-ranges = <&pinctrl 0 48 16>;
+ };
+
+ A device node willing to use pins controlled by this GPIO controller, shall
+ refer to it as follows:
+
+ led1 {
+ gpios = <&port3 10 GPIO_ACTIVE_LOW>;
+ };