// 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/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");