Commit a22ddeef authored by Kamel Bouhara's avatar Kamel Bouhara Committed by Lee Jones
Browse files

mfd: Add max7360 support 



Add core driver to support MAX7360 i2c chip, multi function device
with keypad, GPIO, PWM, GPO and rotary encoder submodules.

Signed-off-by: default avatarKamel Bouhara <kamel.bouhara@bootlin.com>
Co-developed-by: default avatarMathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: default avatarMathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250824-mdb-max7360-support-v14-2-435cfda2b1ea@bootlin.com


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent aee81445

drivers/mfd/Kconfig

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@@ -2481,5 +2481,19 @@ config MFD_UPBOARD_FPGA 
	  To compile this driver as a module, choose M here: the module will be

	  called upboard-fpga.



config MFD_MAX7360

	tristate "Maxim MAX7360 I2C IO Expander"

	depends on I2C

	select MFD_CORE

	select REGMAP_I2C

	select REGMAP_IRQ

	help

	  Say yes here to add support for Maxim MAX7360 device, embedding

	  keypad, rotary encoder, PWM and GPIO features.



	  This driver provides common support for accessing the device;

	  additional drivers must be enabled in order to use the functionality

	  of the device.



endmenu

endif

drivers/mfd/Makefile

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@@ -163,6 +163,7 @@ obj-$(CONFIG_MFD_DA9063) += da9063.o 
obj-$(CONFIG_MFD_DA9150)	+= da9150-core.o



obj-$(CONFIG_MFD_MAX14577)	+= max14577.o

obj-$(CONFIG_MFD_MAX7360)	+= max7360.o

obj-$(CONFIG_MFD_MAX77541)	+= max77541.o

obj-$(CONFIG_MFD_MAX77620)	+= max77620.o

obj-$(CONFIG_MFD_MAX77650)	+= max77650.o

drivers/mfd/max7360.c

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

/*

 * Maxim MAX7360 Core Driver

 *

 * Copyright 2025 Bootlin

 *

 * Authors:

 *    Kamel Bouhara <kamel.bouhara@bootlin.com>

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

 */



#include <linux/array_size.h>

#include <linux/bits.h>

#include <linux/delay.h>

#include <linux/device/devres.h>

#include <linux/dev_printk.h>

#include <linux/err.h>

#include <linux/i2c.h>

#include <linux/interrupt.h>

#include <linux/mfd/core.h>

#include <linux/mfd/max7360.h>

#include <linux/mod_devicetable.h>

#include <linux/module.h>

#include <linux/regmap.h>

#include <linux/types.h>



static const struct mfd_cell max7360_cells[] = {

	{ .name           = "max7360-pinctrl" },

	{ .name           = "max7360-pwm" },

	{ .name           = "max7360-keypad" },

	{ .name           = "max7360-rotary" },

	{

		.name           = "max7360-gpo",

		.of_compatible	= "maxim,max7360-gpo",

	},

	{

		.name           = "max7360-gpio",

		.of_compatible	= "maxim,max7360-gpio",

	},

};



static const struct regmap_range max7360_volatile_ranges[] = {

	regmap_reg_range(MAX7360_REG_KEYFIFO, MAX7360_REG_KEYFIFO),

	regmap_reg_range(MAX7360_REG_I2C_TIMEOUT, MAX7360_REG_RTR_CNT),

};



static const struct regmap_access_table max7360_volatile_table = {

	.yes_ranges = max7360_volatile_ranges,

	.n_yes_ranges = ARRAY_SIZE(max7360_volatile_ranges),

};



static const struct regmap_config max7360_regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,

	.max_register = MAX7360_REG_PWMCFG(MAX7360_PORT_PWM_COUNT - 1),

	.volatile_table = &max7360_volatile_table,

	.cache_type = REGCACHE_MAPLE,

};



static int max7360_mask_irqs(struct regmap *regmap)

{

	struct device *dev = regmap_get_device(regmap);

	unsigned int val;

	int ret;



	/*

	 * GPIO/PWM interrupts are not masked on reset: as the MAX7360 "INTI"

	 * interrupt line is shared between GPIOs and rotary encoder, this could

	 * result in repeated spurious interrupts on the rotary encoder driver

	 * if the GPIO driver is not loaded. Mask them now to avoid this

	 * situation.

	 */

	for (unsigned int i = 0; i < MAX7360_PORT_PWM_COUNT; i++) {

		ret = regmap_write_bits(regmap, MAX7360_REG_PWMCFG(i),

					MAX7360_PORT_CFG_INTERRUPT_MASK,

					MAX7360_PORT_CFG_INTERRUPT_MASK);

		if (ret)

			return dev_err_probe(dev, ret,

					     "Failed to write MAX7360 port configuration\n");

	}



	/* Read GPIO in register, to ACK any pending IRQ. */

	ret = regmap_read(regmap, MAX7360_REG_GPIOIN, &val);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to read GPIO values\n");



	return 0;

}



static int max7360_reset(struct regmap *regmap)

{

	struct device *dev = regmap_get_device(regmap);

	int ret;



	ret = regmap_write(regmap, MAX7360_REG_GPIOCFG, MAX7360_GPIO_CFG_GPIO_RST);

	if (ret) {

		dev_err(dev, "Failed to reset GPIO configuration: %x\n", ret);

		return ret;

	}



	ret = regcache_drop_region(regmap, MAX7360_REG_GPIOCFG, MAX7360_REG_GPIO_LAST);

	if (ret) {

		dev_err(dev, "Failed to drop regmap cache: %x\n", ret);

		return ret;

	}



	ret = regmap_write(regmap, MAX7360_REG_SLEEP, 0);

	if (ret) {

		dev_err(dev, "Failed to reset autosleep configuration: %x\n", ret);

		return ret;

	}



	ret = regmap_write(regmap, MAX7360_REG_DEBOUNCE, 0);

	if (ret)

		dev_err(dev, "Failed to reset GPO port count: %x\n", ret);



	return ret;

}



static int max7360_probe(struct i2c_client *client)

{

	struct device *dev = &client->dev;

	struct regmap *regmap;

	int ret;



	regmap = devm_regmap_init_i2c(client, &max7360_regmap_config);

	if (IS_ERR(regmap))

		return dev_err_probe(dev, PTR_ERR(regmap), "Failed to initialise regmap\n");



	ret = max7360_reset(regmap);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to reset device\n");



	/* Get the device out of shutdown mode. */

	ret = regmap_write_bits(regmap, MAX7360_REG_GPIOCFG,

				MAX7360_GPIO_CFG_GPIO_EN,

				MAX7360_GPIO_CFG_GPIO_EN);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to enable GPIO and PWM module\n");



	ret = max7360_mask_irqs(regmap);

	if (ret)

		return dev_err_probe(dev, ret, "Could not mask interrupts\n");



	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,

				   max7360_cells, ARRAY_SIZE(max7360_cells),

				   NULL, 0, NULL);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to register child devices\n");



	return 0;

}



static const struct of_device_id max7360_dt_match[] = {

	{ .compatible = "maxim,max7360" },

	{}

};

MODULE_DEVICE_TABLE(of, max7360_dt_match);



static struct i2c_driver max7360_driver = {

	.driver = {

		.name = "max7360",

		.of_match_table = max7360_dt_match,

	},

	.probe = max7360_probe,

};

module_i2c_driver(max7360_driver);



MODULE_DESCRIPTION("Maxim MAX7360 I2C IO Expander core driver");

MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>");

MODULE_LICENSE("GPL");

include/linux/mfd/max7360.h

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



#ifndef __LINUX_MFD_MAX7360_H

#define __LINUX_MFD_MAX7360_H



#include <linux/bits.h>



#define MAX7360_MAX_KEY_ROWS		8

#define MAX7360_MAX_KEY_COLS		8

#define MAX7360_MAX_KEY_NUM		(MAX7360_MAX_KEY_ROWS * MAX7360_MAX_KEY_COLS)

#define MAX7360_ROW_SHIFT		3



#define MAX7360_MAX_GPIO		8

#define MAX7360_MAX_GPO			6

#define MAX7360_PORT_PWM_COUNT		8

#define MAX7360_PORT_RTR_PIN		(MAX7360_PORT_PWM_COUNT - 1)



/*

 * MAX7360 registers

 */

#define MAX7360_REG_KEYFIFO		0x00

#define MAX7360_REG_CONFIG		0x01

#define MAX7360_REG_DEBOUNCE		0x02

#define MAX7360_REG_INTERRUPT		0x03

#define MAX7360_REG_PORTS		0x04

#define MAX7360_REG_KEYREP		0x05

#define MAX7360_REG_SLEEP		0x06



/*

 * MAX7360 GPIO registers

 *

 * All these registers are reset together when writing bit 3 of

 * MAX7360_REG_GPIOCFG.

 */

#define MAX7360_REG_GPIOCFG		0x40

#define MAX7360_REG_GPIOCTRL		0x41

#define MAX7360_REG_GPIODEB		0x42

#define MAX7360_REG_GPIOCURR		0x43

#define MAX7360_REG_GPIOOUTM		0x44

#define MAX7360_REG_PWMCOM		0x45

#define MAX7360_REG_RTRCFG		0x46

#define MAX7360_REG_I2C_TIMEOUT		0x48

#define MAX7360_REG_GPIOIN		0x49

#define MAX7360_REG_RTR_CNT		0x4A

#define MAX7360_REG_PWMBASE		0x50

#define MAX7360_REG_PWMCFGBASE		0x58



#define MAX7360_REG_GPIO_LAST		0x5F



#define MAX7360_REG_PWM(x)		(MAX7360_REG_PWMBASE + (x))

#define MAX7360_REG_PWMCFG(x)		(MAX7360_REG_PWMCFGBASE + (x))



/*

 * Configuration register bits

 */

#define MAX7360_FIFO_EMPTY		0x3F

#define MAX7360_FIFO_OVERFLOW		0x7F

#define MAX7360_FIFO_RELEASE		BIT(6)

#define MAX7360_FIFO_COL		GENMASK(5, 3)

#define MAX7360_FIFO_ROW		GENMASK(2, 0)



#define MAX7360_CFG_SLEEP		BIT(7)

#define MAX7360_CFG_INTERRUPT		BIT(5)

#define MAX7360_CFG_KEY_RELEASE		BIT(3)

#define MAX7360_CFG_WAKEUP		BIT(1)

#define MAX7360_CFG_TIMEOUT		BIT(0)



#define MAX7360_DEBOUNCE		GENMASK(4, 0)

#define MAX7360_DEBOUNCE_MIN		9

#define MAX7360_DEBOUNCE_MAX		40

#define MAX7360_PORTS			GENMASK(8, 5)



#define MAX7360_INTERRUPT_TIME_MASK	GENMASK(4, 0)

#define MAX7360_INTERRUPT_FIFO_MASK	GENMASK(7, 5)



#define MAX7360_PORT_CFG_INTERRUPT_MASK		BIT(7)

#define MAX7360_PORT_CFG_INTERRUPT_EDGES	BIT(6)

#define MAX7360_PORT_CFG_COMMON_PWM		BIT(5)



/*

 * Autosleep register values

 */

#define MAX7360_AUTOSLEEP_8192MS	0x01

#define MAX7360_AUTOSLEEP_4096MS	0x02

#define MAX7360_AUTOSLEEP_2048MS	0x03

#define MAX7360_AUTOSLEEP_1024MS	0x04

#define MAX7360_AUTOSLEEP_512MS		0x05

#define MAX7360_AUTOSLEEP_256MS		0x06



#define MAX7360_GPIO_CFG_RTR_EN		BIT(7)

#define MAX7360_GPIO_CFG_GPIO_EN	BIT(4)

#define MAX7360_GPIO_CFG_GPIO_RST	BIT(3)



#define MAX7360_ROT_DEBOUNCE		GENMASK(3, 0)

#define MAX7360_ROT_DEBOUNCE_MIN	0

#define MAX7360_ROT_DEBOUNCE_MAX	15

#define MAX7360_ROT_INTCNT		GENMASK(6, 4)

#define MAX7360_ROT_INTCNT_DLY		BIT(7)



#define MAX7360_INT_INTI		0

#define MAX7360_INT_INTK		1



#define MAX7360_INT_GPIO		0

#define MAX7360_INT_KEYPAD		1

#define MAX7360_INT_ROTARY		2



#define MAX7360_NR_INTERNAL_IRQS	3



#endif