dt-bindings: pinctrl: Add RZ/A2 pinctrl and GPIO

Renesas RZ/A2 combined Pin and GPIO controller

The Renesas SoCs of the RZ/A2 series feature a combined Pin and GPIO controller.

Pin multiplexing and GPIO configuration is performed on a per-pin basis.

Each port features up to 8 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: shall be:

    - "renesas,r7s9210-pinctrl": for RZ/A2M

  - reg

    Address base and length of the memory area where the pin controller

    hardware is mapped to.

  - gpio-controller

    This pin controller also controls pins as GPIO

  - #gpio-cells

    Must be 2

  - gpio-ranges

    Expresses the total number of GPIO ports/pins in this SoC

Example: Pin controller node for RZ/A2M SoC (r7s9210)

	pinctrl: pin-controller@fcffe000 {

		compatible = "renesas,r7s9210-pinctrl";

		reg = <0xfcffe000 0x1000>;

		gpio-controller;

		#gpio-cells = <2>;

		gpio-ranges = <&pinctrl 0 0 176>;

	};

Sub-nodes

---------

The child nodes of the pin controller designate pins to be used for

specific peripheral functions or as GPIO.

- 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.

  The values for the pinmux properties are a combination of port name, pin

  number and the desired function index. Use the RZA2_PINMUX macro located

  in include/dt-bindings/pinctrl/r7s9210-pinctrl.h to easily define these.

  For assigning GPIO pins, use the macro RZA2_PIN also in r7s9210-pinctrl.h

  to express the desired port pin.

  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:

      <dt-bindings/pinctrl/r7s9210-pinctrl.h>

      Integers values in "pinmux" argument list are assembled as:

      ((PORT * 8 + PIN) | MUX_FUNC << 16)

  Example: Board specific pins configuration

	&pinctrl {

		/* Serial Console */

		scif4_pins: serial4 {

			pinmux = <RZA2_PINMUX(PORT9, 0, 4)>,	/* TxD4 */

				 <RZA2_PINMUX(PORT9, 1, 4)>;	/* RxD4 */

		};

	};

  Example: Assigning a GPIO:

	leds {

		status = "okay";

		compatible = "gpio-leds";

		led0 {

			/* P6_0 */

			gpios = <&pinctrl RZA2_PIN(PORT6, 0) GPIO_ACTIVE_HIGH>;

		};

	};

/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Defines macros and constants for Renesas RZ/A2 pin controller pin

 * muxing functions.

 */

#ifndef __DT_BINDINGS_PINCTRL_RENESAS_RZA2_H

#define __DT_BINDINGS_PINCTRL_RENESAS_RZA2_H

#define RZA2_PINS_PER_PORT	8

/* Port names as labeled in the Hardware Manual */

#define PORT0 0

#define PORT1 1

#define PORT2 2

#define PORT3 3

#define PORT4 4

#define PORT5 5

#define PORT6 6

#define PORT7 7

#define PORT8 8

#define PORT9 9

#define PORTA 10

#define PORTB 11

#define PORTC 12

#define PORTD 13

#define PORTE 14

#define PORTF 15

#define PORTG 16

#define PORTH 17

/* No I */

#define PORTJ 18

#define PORTK 19

#define PORTL 20

#define PORTM 21	/* Pins PM_0/1 are labeled JP_0/1 in HW manual */

/*

 * Create the pin index from its bank and position numbers and store in

 * the upper 16 bits the alternate function identifier

 */

#define RZA2_PINMUX(b, p, f)	((b) * RZA2_PINS_PER_PORT + (p) | (f << 16))

/*

 * Convert a port and pin label to its global pin index

 */

 #define RZA2_PIN(port, pin)	((port) * RZA2_PINS_PER_PORT + (pin))

#endif /* __DT_BINDINGS_PINCTRL_RENESAS_RZA2_H */