Commit fa6a23f1 authored by Mathieu Dubois-Briand's avatar Mathieu Dubois-Briand Committed by Lee Jones
Browse files

input: keyboard: Add support for MAX7360 keypad 



Add driver for Maxim Integrated MAX7360 keypad controller, providing
support for up to 64 keys, with a matrix of 8 columns and 8 rows.

Acked-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: default avatarMathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Link: https://lore.kernel.org/r/20250824-mdb-max7360-support-v14-8-435cfda2b1ea@bootlin.com


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent b1a7433d

drivers/input/keyboard/Kconfig

+12 −0
Original line number Diff line number Diff line
@@ -422,6 +422,18 @@ config KEYBOARD_MAX7359 
	  To compile this driver as a module, choose M here: the

	  module will be called max7359_keypad.



config KEYBOARD_MAX7360

	tristate "Maxim MAX7360 Key Switch Controller"

	select INPUT_MATRIXKMAP

	depends on I2C

	depends on MFD_MAX7360

	help

	  If you say yes here you get support for the keypad controller on the

	  Maxim MAX7360 I/O Expander.



	  To compile this driver as a module, choose M here: the module will be

	  called max7360_keypad.



config KEYBOARD_MPR121

	tristate "Freescale MPR121 Touchkey"

	depends on I2C

drivers/input/keyboard/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ obj-$(CONFIG_KEYBOARD_LPC32XX) += lpc32xx-keys.o 
obj-$(CONFIG_KEYBOARD_MAPLE)		+= maple_keyb.o

obj-$(CONFIG_KEYBOARD_MATRIX)		+= matrix_keypad.o

obj-$(CONFIG_KEYBOARD_MAX7359)		+= max7359_keypad.o

obj-$(CONFIG_KEYBOARD_MAX7360)		+= max7360-keypad.o

obj-$(CONFIG_KEYBOARD_MPR121)		+= mpr121_touchkey.o

obj-$(CONFIG_KEYBOARD_MT6779)		+= mt6779-keypad.o

obj-$(CONFIG_KEYBOARD_MTK_PMIC) 	+= mtk-pmic-keys.o

drivers/input/keyboard/max7360-keypad.c

0 → 100644
+308 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright 2025 Bootlin

 *

 * Author: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>

 */



#include <linux/bitfield.h>

#include <linux/bitops.h>

#include <linux/dev_printk.h>

#include <linux/device/devres.h>

#include <linux/err.h>

#include <linux/init.h>

#include <linux/input.h>

#include <linux/input/matrix_keypad.h>

#include <linux/interrupt.h>

#include <linux/mfd/max7360.h>

#include <linux/mod_devicetable.h>

#include <linux/minmax.h>

#include <linux/module.h>

#include <linux/property.h>

#include <linux/platform_device.h>

#include <linux/pm_wakeirq.h>

#include <linux/regmap.h>



struct max7360_keypad {

	struct input_dev *input;

	unsigned int rows;

	unsigned int cols;

	unsigned int debounce_ms;

	int irq;

	struct regmap *regmap;

	unsigned short keycodes[MAX7360_MAX_KEY_ROWS * MAX7360_MAX_KEY_COLS];

};



static irqreturn_t max7360_keypad_irq(int irq, void *data)

{

	struct max7360_keypad *max7360_keypad = data;

	struct device *dev = max7360_keypad->input->dev.parent;

	unsigned int val;

	unsigned int row, col;

	unsigned int release;

	unsigned int code;

	int error;



	error = regmap_read(max7360_keypad->regmap, MAX7360_REG_KEYFIFO, &val);

	if (error) {

		dev_err(dev, "Failed to read MAX7360 FIFO");

		return IRQ_NONE;

	}



	/* FIFO overflow: ignore it and get next event. */

	if (val == MAX7360_FIFO_OVERFLOW) {

		dev_warn(dev, "max7360 FIFO overflow");

		error = regmap_read_poll_timeout(max7360_keypad->regmap, MAX7360_REG_KEYFIFO,

						 val, val != MAX7360_FIFO_OVERFLOW, 0, 1000);

		if (error) {

			dev_err(dev, "Failed to empty MAX7360 FIFO");

			return IRQ_NONE;

		}

	}



	if (val == MAX7360_FIFO_EMPTY) {

		dev_dbg(dev, "Got a spurious interrupt");



		return IRQ_NONE;

	}



	row = FIELD_GET(MAX7360_FIFO_ROW, val);

	col = FIELD_GET(MAX7360_FIFO_COL, val);

	release = val & MAX7360_FIFO_RELEASE;



	code = MATRIX_SCAN_CODE(row, col, get_count_order(max7360_keypad->cols));



	dev_dbg(dev, "key[%d:%d] %s\n", row, col, release ? "release" : "press");



	input_event(max7360_keypad->input, EV_MSC, MSC_SCAN, code);

	input_report_key(max7360_keypad->input, max7360_keypad->keycodes[code], !release);

	input_sync(max7360_keypad->input);



	return IRQ_HANDLED;

}



static int max7360_keypad_open(struct input_dev *pdev)

{

	struct max7360_keypad *max7360_keypad = input_get_drvdata(pdev);

	struct device *dev = max7360_keypad->input->dev.parent;

	int error;



	/* Somebody is using the device: get out of sleep. */

	error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_CONFIG,

				  MAX7360_CFG_SLEEP, MAX7360_CFG_SLEEP);

	if (error)

		dev_err(dev, "Failed to write max7360 configuration: %d\n", error);



	return error;

}



static void max7360_keypad_close(struct input_dev *pdev)

{

	struct max7360_keypad *max7360_keypad = input_get_drvdata(pdev);

	struct device *dev = max7360_keypad->input->dev.parent;

	int error;



	/* Nobody is using the device anymore: go to sleep. */

	error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_CONFIG, MAX7360_CFG_SLEEP, 0);

	if (error)

		dev_err(dev, "Failed to write max7360 configuration: %d\n", error);

}



static int max7360_keypad_hw_init(struct max7360_keypad *max7360_keypad)

{

	struct device *dev = max7360_keypad->input->dev.parent;

	unsigned int val;

	int error;



	val = max7360_keypad->debounce_ms - MAX7360_DEBOUNCE_MIN;

	error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_DEBOUNCE,

				  MAX7360_DEBOUNCE,

				  FIELD_PREP(MAX7360_DEBOUNCE, val));

	if (error)

		return dev_err_probe(dev, error,

				     "Failed to write max7360 debounce configuration\n");



	error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_INTERRUPT,

				  MAX7360_INTERRUPT_TIME_MASK,

				  FIELD_PREP(MAX7360_INTERRUPT_TIME_MASK, 1));

	if (error)

		return dev_err_probe(dev, error,

				     "Failed to write max7360 keypad interrupt configuration\n");



	return 0;

}



static int max7360_keypad_build_keymap(struct max7360_keypad *max7360_keypad)

{

	struct input_dev *input_dev = max7360_keypad->input;

	struct device *dev = input_dev->dev.parent->parent;

	struct matrix_keymap_data keymap_data;

	const char *propname = "linux,keymap";

	unsigned int max_keys;

	int error;

	int size;



	size = device_property_count_u32(dev, propname);

	if (size <= 0) {

		dev_err(dev, "missing or malformed property %s: %d\n", propname, size);

		return size < 0 ? size : -EINVAL;

	}



	max_keys = max7360_keypad->cols * max7360_keypad->rows;

	if (size > max_keys) {

		dev_err(dev, "%s size overflow (%d vs max %u)\n", propname, size, max_keys);

		return -EINVAL;

	}



	u32 *keys __free(kfree) = kmalloc_array(size, sizeof(*keys), GFP_KERNEL);

	if (!keys)

		return -ENOMEM;



	error = device_property_read_u32_array(dev, propname, keys, size);

	if (error) {

		dev_err(dev, "failed to read %s property: %d\n", propname, error);

		return error;

	}



	keymap_data.keymap = keys;

	keymap_data.keymap_size = size;

	error = matrix_keypad_build_keymap(&keymap_data, NULL,

					   max7360_keypad->rows, max7360_keypad->cols,

					   max7360_keypad->keycodes, max7360_keypad->input);

	if (error)

		return error;



	return 0;

}



static int max7360_keypad_parse_fw(struct device *dev,

				   struct max7360_keypad *max7360_keypad,

				   bool *autorepeat)

{

	int error;



	error = matrix_keypad_parse_properties(dev->parent, &max7360_keypad->rows,

					       &max7360_keypad->cols);

	if (error)

		return error;



	if (!max7360_keypad->rows || !max7360_keypad->cols ||

	    max7360_keypad->rows > MAX7360_MAX_KEY_ROWS ||

	    max7360_keypad->cols > MAX7360_MAX_KEY_COLS) {

		dev_err(dev, "Invalid number of columns or rows (%ux%u)\n",

			max7360_keypad->cols, max7360_keypad->rows);

		return -EINVAL;

	}



	*autorepeat = device_property_read_bool(dev->parent, "autorepeat");



	max7360_keypad->debounce_ms = MAX7360_DEBOUNCE_MIN;

	error = device_property_read_u32(dev->parent, "keypad-debounce-delay-ms",

					 &max7360_keypad->debounce_ms);

	if (error == -EINVAL) {

		dev_info(dev, "Using default keypad-debounce-delay-ms: %u\n",

			 max7360_keypad->debounce_ms);

	} else if (error < 0) {

		dev_err(dev, "Failed to read keypad-debounce-delay-ms property\n");

		return error;

	}



	if (!in_range(max7360_keypad->debounce_ms, MAX7360_DEBOUNCE_MIN,

		      MAX7360_DEBOUNCE_MAX - MAX7360_DEBOUNCE_MIN + 1)) {

		dev_err(dev, "Invalid keypad-debounce-delay-ms: %u, should be between %u and %u.\n",

			max7360_keypad->debounce_ms, MAX7360_DEBOUNCE_MIN, MAX7360_DEBOUNCE_MAX);

		return -EINVAL;

	}



	return 0;

}



static int max7360_keypad_probe(struct platform_device *pdev)

{

	struct max7360_keypad *max7360_keypad;

	struct device *dev = &pdev->dev;

	struct input_dev *input;

	struct regmap *regmap;

	bool autorepeat;

	int error;

	int irq;



	regmap = dev_get_regmap(dev->parent, NULL);

	if (!regmap)

		return dev_err_probe(dev, -ENODEV, "Could not get parent regmap\n");



	irq = fwnode_irq_get_byname(dev_fwnode(dev->parent), "intk");

	if (irq < 0)

		return dev_err_probe(dev, irq, "Failed to get IRQ\n");



	max7360_keypad = devm_kzalloc(dev, sizeof(*max7360_keypad), GFP_KERNEL);

	if (!max7360_keypad)

		return -ENOMEM;



	max7360_keypad->regmap = regmap;



	error = max7360_keypad_parse_fw(dev, max7360_keypad, &autorepeat);

	if (error)

		return error;



	input = devm_input_allocate_device(dev);

	if (!input)

		return -ENOMEM;



	max7360_keypad->input = input;



	input->id.bustype = BUS_I2C;

	input->name = pdev->name;

	input->open = max7360_keypad_open;

	input->close = max7360_keypad_close;



	error = max7360_keypad_build_keymap(max7360_keypad);

	if (error)

		return dev_err_probe(dev, error, "Failed to build keymap\n");



	input_set_capability(input, EV_MSC, MSC_SCAN);

	if (autorepeat)

		__set_bit(EV_REP, input->evbit);



	input_set_drvdata(input, max7360_keypad);



	error = devm_request_threaded_irq(dev, irq, NULL, max7360_keypad_irq,

					  IRQF_ONESHOT,

					  "max7360-keypad", max7360_keypad);

	if (error)

		return dev_err_probe(dev, error, "Failed to register interrupt\n");



	error = input_register_device(input);

	if (error)

		return dev_err_probe(dev, error, "Could not register input device\n");



	error = max7360_keypad_hw_init(max7360_keypad);

	if (error)

		return dev_err_probe(dev, error, "Failed to initialize max7360 keypad\n");



	device_init_wakeup(dev, true);

	error = dev_pm_set_wake_irq(dev, irq);

	if (error)

		dev_warn(dev, "Failed to set up wakeup irq: %d\n", error);



	return 0;

}



static void max7360_keypad_remove(struct platform_device *pdev)

{

	dev_pm_clear_wake_irq(&pdev->dev);

	device_init_wakeup(&pdev->dev, false);

}



static struct platform_driver max7360_keypad_driver = {

	.driver = {

		.name	= "max7360-keypad",

	},

	.probe		= max7360_keypad_probe,

	.remove		= max7360_keypad_remove,

};

module_platform_driver(max7360_keypad_driver);



MODULE_DESCRIPTION("MAX7360 Keypad driver");

MODULE_AUTHOR("Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>");

MODULE_LICENSE("GPL");