mfd: max77620: Add core driver for MAX77620/MAX20024

MAX77620/MAX20024 are Power Management IC from the MAXIM.
It supports RTC, multiple GPIOs, multiple DCDC and LDOs,
watchdog, clock etc.

Add MFD drier to provides common support for accessing the
device; additional drivers is developed on respected subsystem
in order to use the functionality of the device.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mallikarjun Kasoju <mkasoju@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index cf7cbba..16d0bef 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -527,6 +527,21 @@
 	  additional drivers must be enabled in order to use the functionality
 	  of the device.
 
+config MFD_MAX77620
+	bool "Maxim Semiconductor MAX77620 and MAX20024 PMIC Support"
+	depends on I2C=y
+	depends on OF
+	select MFD_CORE
+	select REGMAP_I2C
+	select REGMAP_IRQ
+	select IRQ_DOMAIN
+	help
+	  Say yes here to add support for Maxim Semiconductor MAX77620 and
+	  MAX20024 which are Power Management IC with General purpose pins,
+	  RTC, regulators, clock generator, watchdog etc. This driver
+	  provides common support for accessing the device; additional drivers
+	  must be enabled in order to use the functionality of the device.
+
 config MFD_MAX77686
 	tristate "Maxim Semiconductor MAX77686/802 PMIC Support"
 	depends on I2C
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5eaa6465d..921a08d 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -128,6 +128,7 @@
 obj-$(CONFIG_MFD_DA9150)	+= da9150-core.o
 
 obj-$(CONFIG_MFD_MAX14577)	+= max14577.o
+obj-$(CONFIG_MFD_MAX77620)	+= max77620.o
 obj-$(CONFIG_MFD_MAX77686)	+= max77686.o
 obj-$(CONFIG_MFD_MAX77693)	+= max77693.o
 obj-$(CONFIG_MFD_MAX77843)	+= max77843.o
diff --git a/drivers/mfd/max77620.c b/drivers/mfd/max77620.c
new file mode 100644
index 0000000..199d261
--- /dev/null
+++ b/drivers/mfd/max77620.c
@@ -0,0 +1,590 @@
+/*
+ * Maxim MAX77620 MFD Driver
+ *
+ * Copyright (C) 2016 NVIDIA CORPORATION. All rights reserved.
+ *
+ * Author:
+ *	Laxman Dewangan <ldewangan@nvidia.com>
+ *	Chaitanya Bandi <bandik@nvidia.com>
+ *	Mallikarjun Kasoju <mkasoju@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/****************** Teminology used in driver ********************
+ * Here are some terminology used from datasheet for quick reference:
+ * Flexible Power Sequence (FPS):
+ * The Flexible Power Sequencer (FPS) allows each regulator to power up under
+ * hardware or software control. Additionally, each regulator can power on
+ * independently or among a group of other regulators with an adjustable
+ * power-up and power-down delays (sequencing). GPIO1, GPIO2, and GPIO3 can
+ * be programmed to be part of a sequence allowing external regulators to be
+ * sequenced along with internal regulators. 32KHz clock can be programmed to
+ * be part of a sequence.
+ * There is 3 FPS confguration registers and all resources are configured to
+ * any of these FPS or no FPS.
+ */
+
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/max77620.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+static struct resource gpio_resources[] = {
+	DEFINE_RES_IRQ(MAX77620_IRQ_TOP_GPIO),
+};
+
+static struct resource power_resources[] = {
+	DEFINE_RES_IRQ(MAX77620_IRQ_LBT_MBATLOW),
+};
+
+static struct resource rtc_resources[] = {
+	DEFINE_RES_IRQ(MAX77620_IRQ_TOP_RTC),
+};
+
+static struct resource thermal_resources[] = {
+	DEFINE_RES_IRQ(MAX77620_IRQ_LBT_TJALRM1),
+	DEFINE_RES_IRQ(MAX77620_IRQ_LBT_TJALRM2),
+};
+
+static const struct regmap_irq max77620_top_irqs[] = {
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_GLBL, 0, MAX77620_IRQ_TOP_GLBL_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_SD, 0, MAX77620_IRQ_TOP_SD_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_LDO, 0, MAX77620_IRQ_TOP_LDO_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_GPIO, 0, MAX77620_IRQ_TOP_GPIO_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_RTC, 0, MAX77620_IRQ_TOP_RTC_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_32K, 0, MAX77620_IRQ_TOP_32K_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_TOP_ONOFF, 0, MAX77620_IRQ_TOP_ONOFF_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_LBT_MBATLOW, 1, MAX77620_IRQ_LBM_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_LBT_TJALRM1, 1, MAX77620_IRQ_TJALRM1_MASK),
+	REGMAP_IRQ_REG(MAX77620_IRQ_LBT_TJALRM2, 1, MAX77620_IRQ_TJALRM2_MASK),
+};
+
+static const struct mfd_cell max77620_children[] = {
+	{ .name = "max77620-pinctrl", },
+	{ .name = "max77620-clock", },
+	{ .name = "max77620-pmic", },
+	{ .name = "max77620-watchdog", },
+	{
+		.name = "max77620-gpio",
+		.resources = gpio_resources,
+		.num_resources = ARRAY_SIZE(gpio_resources),
+	}, {
+		.name = "max77620-rtc",
+		.resources = rtc_resources,
+		.num_resources = ARRAY_SIZE(rtc_resources),
+	}, {
+		.name = "max77620-power",
+		.resources = power_resources,
+		.num_resources = ARRAY_SIZE(power_resources),
+	}, {
+		.name = "max77620-thermal",
+		.resources = thermal_resources,
+		.num_resources = ARRAY_SIZE(thermal_resources),
+	},
+};
+
+static const struct mfd_cell max20024_children[] = {
+	{ .name = "max20024-pinctrl", },
+	{ .name = "max77620-clock", },
+	{ .name = "max20024-pmic", },
+	{ .name = "max77620-watchdog", },
+	{
+		.name = "max77620-gpio",
+		.resources = gpio_resources,
+		.num_resources = ARRAY_SIZE(gpio_resources),
+	}, {
+		.name = "max77620-rtc",
+		.resources = rtc_resources,
+		.num_resources = ARRAY_SIZE(rtc_resources),
+	}, {
+		.name = "max20024-power",
+		.resources = power_resources,
+		.num_resources = ARRAY_SIZE(power_resources),
+	},
+};
+
+static struct regmap_irq_chip max77620_top_irq_chip = {
+	.name = "max77620-top",
+	.irqs = max77620_top_irqs,
+	.num_irqs = ARRAY_SIZE(max77620_top_irqs),
+	.num_regs = 2,
+	.status_base = MAX77620_REG_IRQTOP,
+	.mask_base = MAX77620_REG_IRQTOPM,
+};
+
+static const struct regmap_range max77620_readable_ranges[] = {
+	regmap_reg_range(MAX77620_REG_CNFGGLBL1, MAX77620_REG_DVSSD4),
+};
+
+static const struct regmap_access_table max77620_readable_table = {
+	.yes_ranges = max77620_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(max77620_readable_ranges),
+};
+
+static const struct regmap_range max20024_readable_ranges[] = {
+	regmap_reg_range(MAX77620_REG_CNFGGLBL1, MAX77620_REG_DVSSD4),
+	regmap_reg_range(MAX20024_REG_MAX_ADD, MAX20024_REG_MAX_ADD),
+};
+
+static const struct regmap_access_table max20024_readable_table = {
+	.yes_ranges = max20024_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(max20024_readable_ranges),
+};
+
+static const struct regmap_range max77620_writable_ranges[] = {
+	regmap_reg_range(MAX77620_REG_CNFGGLBL1, MAX77620_REG_DVSSD4),
+};
+
+static const struct regmap_access_table max77620_writable_table = {
+	.yes_ranges = max77620_writable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(max77620_writable_ranges),
+};
+
+static const struct regmap_range max77620_cacheable_ranges[] = {
+	regmap_reg_range(MAX77620_REG_SD0_CFG, MAX77620_REG_LDO_CFG3),
+	regmap_reg_range(MAX77620_REG_FPS_CFG0, MAX77620_REG_FPS_SD3),
+};
+
+static const struct regmap_access_table max77620_volatile_table = {
+	.no_ranges = max77620_cacheable_ranges,
+	.n_no_ranges = ARRAY_SIZE(max77620_cacheable_ranges),
+};
+
+static const struct regmap_config max77620_regmap_config = {
+	.name = "power-slave",
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX77620_REG_DVSSD4 + 1,
+	.cache_type = REGCACHE_RBTREE,
+	.rd_table = &max77620_readable_table,
+	.wr_table = &max77620_writable_table,
+	.volatile_table = &max77620_volatile_table,
+};
+
+static const struct regmap_config max20024_regmap_config = {
+	.name = "power-slave",
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX20024_REG_MAX_ADD + 1,
+	.cache_type = REGCACHE_RBTREE,
+	.rd_table = &max20024_readable_table,
+	.wr_table = &max77620_writable_table,
+	.volatile_table = &max77620_volatile_table,
+};
+
+/* max77620_get_fps_period_reg_value:  Get FPS bit field value from
+ *				       requested periods.
+ * MAX77620 supports the FPS period of 40, 80, 160, 320, 540, 1280, 2560
+ * and 5120 microseconds. MAX20024 supports the FPS period of 20, 40, 80,
+ * 160, 320, 540, 1280 and 2560 microseconds.
+ * The FPS register has 3 bits field to set the FPS period as
+ * bits		max77620		max20024
+ * 000		40			20
+ * 001		80			40
+ * :::
+*/
+static int max77620_get_fps_period_reg_value(struct max77620_chip *chip,
+					     int tperiod)
+{
+	int fps_min_period;
+	int i;
+
+	switch (chip->chip_id) {
+	case MAX20024:
+		fps_min_period = MAX20024_FPS_PERIOD_MIN_US;
+		break;
+	case MAX77620:
+		fps_min_period = MAX77620_FPS_PERIOD_MIN_US;
+	default:
+		return -EINVAL;
+	}
+
+	for (i = 0; i < 7; i++) {
+		if (fps_min_period >= tperiod)
+			return i;
+		fps_min_period *= 2;
+	}
+
+	return i;
+}
+
+/* max77620_config_fps: Configure FPS configuration registers
+ *			based on platform specific information.
+ */
+static int max77620_config_fps(struct max77620_chip *chip,
+			       struct device_node *fps_np)
+{
+	struct device *dev = chip->dev;
+	unsigned int mask = 0, config = 0;
+	u32 fps_max_period;
+	u32 param_val;
+	int tperiod, fps_id;
+	int ret;
+	char fps_name[10];
+
+	switch (chip->chip_id) {
+	case MAX20024:
+		fps_max_period = MAX20024_FPS_PERIOD_MAX_US;
+		break;
+	case MAX77620:
+		fps_max_period = MAX77620_FPS_PERIOD_MAX_US;
+	default:
+		return -EINVAL;
+	}
+
+	for (fps_id = 0; fps_id < MAX77620_FPS_COUNT; fps_id++) {
+		sprintf(fps_name, "fps%d", fps_id);
+		if (!strcmp(fps_np->name, fps_name))
+			break;
+	}
+
+	if (fps_id == MAX77620_FPS_COUNT) {
+		dev_err(dev, "FPS node name %s is not valid\n", fps_np->name);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(fps_np, "maxim,shutdown-fps-time-period-us",
+				   &param_val);
+	if (!ret) {
+		mask |= MAX77620_FPS_TIME_PERIOD_MASK;
+		chip->shutdown_fps_period[fps_id] = min(param_val,
+							fps_max_period);
+		tperiod = max77620_get_fps_period_reg_value(chip,
+				chip->shutdown_fps_period[fps_id]);
+		config |= tperiod << MAX77620_FPS_TIME_PERIOD_SHIFT;
+	}
+
+	ret = of_property_read_u32(fps_np, "maxim,suspend-fps-time-period-us",
+				   &param_val);
+	if (!ret)
+		chip->suspend_fps_period[fps_id] = min(param_val,
+						       fps_max_period);
+
+	ret = of_property_read_u32(fps_np, "maxim,fps-event-source",
+				   &param_val);
+	if (!ret) {
+		if (param_val > 2) {
+			dev_err(dev, "FPS%d event-source invalid\n", fps_id);
+			return -EINVAL;
+		}
+		mask |= MAX77620_FPS_EN_SRC_MASK;
+		config |= param_val << MAX77620_FPS_EN_SRC_SHIFT;
+		if (param_val == 2) {
+			mask |= MAX77620_FPS_ENFPS_SW_MASK;
+			config |= MAX77620_FPS_ENFPS_SW;
+		}
+	}
+
+	if (!chip->sleep_enable && !chip->enable_global_lpm) {
+		ret = of_property_read_u32(fps_np,
+				"maxim,device-state-on-disabled-event",
+				&param_val);
+		if (!ret) {
+			if (param_val == 0)
+				chip->sleep_enable = true;
+			else if (param_val == 1)
+				chip->enable_global_lpm = true;
+		}
+	}
+
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_FPS_CFG0 + fps_id,
+				 mask, config);
+	if (ret < 0) {
+		dev_err(dev, "Failed to update FPS CFG: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int max77620_initialise_fps(struct max77620_chip *chip)
+{
+	struct device *dev = chip->dev;
+	struct device_node *fps_np, *fps_child;
+	u8 config;
+	int fps_id;
+	int ret;
+
+	for (fps_id = 0; fps_id < MAX77620_FPS_COUNT; fps_id++) {
+		chip->shutdown_fps_period[fps_id] = -1;
+		chip->suspend_fps_period[fps_id] = -1;
+	}
+
+	fps_np = of_get_child_by_name(dev->of_node, "fps");
+	if (!fps_np)
+		goto skip_fps;
+
+	for_each_child_of_node(fps_np, fps_child) {
+		ret = max77620_config_fps(chip, fps_child);
+		if (ret < 0)
+			return ret;
+	}
+
+	config = chip->enable_global_lpm ? MAX77620_ONOFFCNFG2_SLP_LPM_MSK : 0;
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG2,
+				 MAX77620_ONOFFCNFG2_SLP_LPM_MSK, config);
+	if (ret < 0) {
+		dev_err(dev, "Failed to update SLP_LPM: %d\n", ret);
+		return ret;
+	}
+
+skip_fps:
+	/* Enable wake on EN0 pin */
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG2,
+				 MAX77620_ONOFFCNFG2_WK_EN0,
+				 MAX77620_ONOFFCNFG2_WK_EN0);
+	if (ret < 0) {
+		dev_err(dev, "Failed to update WK_EN0: %d\n", ret);
+		return ret;
+	}
+
+	/* For MAX20024, SLPEN will be POR reset if CLRSE is b11 */
+	if ((chip->chip_id == MAX20024) && chip->sleep_enable) {
+		config = MAX77620_ONOFFCNFG1_SLPEN | MAX20024_ONOFFCNFG1_CLRSE;
+		ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG1,
+					 config, config);
+		if (ret < 0) {
+			dev_err(dev, "Failed to update SLPEN: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int max77620_read_es_version(struct max77620_chip *chip)
+{
+	unsigned int val;
+	u8 cid_val[6];
+	int i;
+	int ret;
+
+	for (i = MAX77620_REG_CID0; i <= MAX77620_REG_CID5; i++) {
+		ret = regmap_read(chip->rmap, i, &val);
+		if (ret < 0) {
+			dev_err(chip->dev, "Failed to read CID: %d\n", ret);
+			return ret;
+		}
+		dev_dbg(chip->dev, "CID%d: 0x%02x\n",
+			i - MAX77620_REG_CID0, val);
+		cid_val[i - MAX77620_REG_CID0] = val;
+	}
+
+	/* CID4 is OTP Version  and CID5 is ES version */
+	dev_info(chip->dev, "PMIC Version OTP:0x%02X and ES:0x%X\n",
+		 cid_val[4], MAX77620_CID5_DIDM(cid_val[5]));
+
+	return ret;
+}
+
+static int max77620_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	const struct regmap_config *rmap_config;
+	struct max77620_chip *chip;
+	const struct mfd_cell *mfd_cells;
+	int n_mfd_cells;
+	int ret;
+
+	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, chip);
+	chip->dev = &client->dev;
+	chip->irq_base = -1;
+	chip->chip_irq = client->irq;
+	chip->chip_id = (enum max77620_chip_id)id->driver_data;
+
+	switch (chip->chip_id) {
+	case MAX77620:
+		mfd_cells = max77620_children;
+		n_mfd_cells = ARRAY_SIZE(max77620_children);
+		rmap_config = &max77620_regmap_config;
+		break;
+	case MAX20024:
+		mfd_cells = max20024_children;
+		n_mfd_cells = ARRAY_SIZE(max20024_children);
+		rmap_config = &max20024_regmap_config;
+		break;
+	default:
+		dev_err(chip->dev, "ChipID is invalid %d\n", chip->chip_id);
+		return -EINVAL;
+	}
+
+	chip->rmap = devm_regmap_init_i2c(client, rmap_config);
+	if (IS_ERR(chip->rmap)) {
+		ret = PTR_ERR(chip->rmap);
+		dev_err(chip->dev, "Failed to intialise regmap: %d\n", ret);
+		return ret;
+	}
+
+	ret = max77620_read_es_version(chip);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_regmap_add_irq_chip(chip->dev, chip->rmap, client->irq,
+				       IRQF_ONESHOT | IRQF_SHARED,
+				       chip->irq_base, &max77620_top_irq_chip,
+				       &chip->top_irq_data);
+	if (ret < 0) {
+		dev_err(chip->dev, "Failed to add regmap irq: %d\n", ret);
+		return ret;
+	}
+
+	ret = max77620_initialise_fps(chip);
+	if (ret < 0)
+		return ret;
+
+	ret =  devm_mfd_add_devices(chip->dev, PLATFORM_DEVID_NONE,
+				    mfd_cells, n_mfd_cells, NULL, 0,
+				    regmap_irq_get_domain(chip->top_irq_data));
+	if (ret < 0) {
+		dev_err(chip->dev, "Failed to add MFD children: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max77620_set_fps_period(struct max77620_chip *chip,
+				   int fps_id, int time_period)
+{
+	int period = max77620_get_fps_period_reg_value(chip, time_period);
+	int ret;
+
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_FPS_CFG0 + fps_id,
+				 MAX77620_FPS_TIME_PERIOD_MASK,
+				 period << MAX77620_FPS_TIME_PERIOD_SHIFT);
+	if (ret < 0) {
+		dev_err(chip->dev, "Failed to update FPS period: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int max77620_i2c_suspend(struct device *dev)
+{
+	struct max77620_chip *chip = dev_get_drvdata(dev);
+	struct i2c_client *client = to_i2c_client(dev);
+	unsigned int config;
+	int fps;
+	int ret;
+
+	for (fps = 0; fps < MAX77620_FPS_COUNT; fps++) {
+		if (chip->suspend_fps_period[fps] < 0)
+			continue;
+
+		ret = max77620_set_fps_period(chip, fps,
+					      chip->suspend_fps_period[fps]);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * For MAX20024: No need to configure SLPEN on suspend as
+	 * it will be configured on Init.
+	 */
+	if (chip->chip_id == MAX20024)
+		goto out;
+
+	config = (chip->sleep_enable) ? MAX77620_ONOFFCNFG1_SLPEN : 0;
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG1,
+				 MAX77620_ONOFFCNFG1_SLPEN,
+				 config);
+	if (ret < 0) {
+		dev_err(dev, "Failed to configure sleep in suspend: %d\n", ret);
+		return ret;
+	}
+
+	/* Disable WK_EN0 */
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG2,
+				 MAX77620_ONOFFCNFG2_WK_EN0, 0);
+	if (ret < 0) {
+		dev_err(dev, "Failed to configure WK_EN in suspend: %d\n", ret);
+		return ret;
+	}
+
+out:
+	disable_irq(client->irq);
+
+	return 0;
+}
+
+static int max77620_i2c_resume(struct device *dev)
+{
+	struct max77620_chip *chip = dev_get_drvdata(dev);
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret;
+	int fps;
+
+	for (fps = 0; fps < MAX77620_FPS_COUNT; fps++) {
+		if (chip->shutdown_fps_period[fps] < 0)
+			continue;
+
+		ret = max77620_set_fps_period(chip, fps,
+					      chip->shutdown_fps_period[fps]);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * For MAX20024: No need to configure WKEN0 on resume as
+	 * it is configured on Init.
+	 */
+	if (chip->chip_id == MAX20024)
+		goto out;
+
+	/* Enable WK_EN0 */
+	ret = regmap_update_bits(chip->rmap, MAX77620_REG_ONOFFCNFG2,
+				 MAX77620_ONOFFCNFG2_WK_EN0,
+				 MAX77620_ONOFFCNFG2_WK_EN0);
+	if (ret < 0) {
+		dev_err(dev, "Failed to configure WK_EN0 n resume: %d\n", ret);
+		return ret;
+	}
+
+out:
+	enable_irq(client->irq);
+
+	return 0;
+}
+#endif
+
+static const struct i2c_device_id max77620_id[] = {
+	{"max77620", MAX77620},
+	{"max20024", MAX20024},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, max77620_id);
+
+static const struct dev_pm_ops max77620_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(max77620_i2c_suspend, max77620_i2c_resume)
+};
+
+static struct i2c_driver max77620_driver = {
+	.driver = {
+		.name = "max77620",
+		.pm = &max77620_pm_ops,
+	},
+	.probe = max77620_probe,
+	.id_table = max77620_id,
+};
+
+module_i2c_driver(max77620_driver);
+
+MODULE_DESCRIPTION("MAX77620/MAX20024 Multi Function Device Core Driver");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_AUTHOR("Chaitanya Bandi <bandik@nvidia.com>");
+MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/max77620.h b/include/linux/mfd/max77620.h
new file mode 100644
index 0000000..3ca0af07
--- /dev/null
+++ b/include/linux/mfd/max77620.h
@@ -0,0 +1,346 @@
+/*
+ * Defining registers address and its bit definitions of MAX77620 and MAX20024
+ *
+ * Copyright (C) 2016 NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#ifndef _MFD_MAX77620_H_
+#define _MFD_MAX77620_H_
+
+#include <linux/types.h>
+
+/* GLOBAL, PMIC, GPIO, FPS, ONOFFC, CID Registers */
+#define MAX77620_REG_CNFGGLBL1			0x00
+#define MAX77620_REG_CNFGGLBL2			0x01
+#define MAX77620_REG_CNFGGLBL3			0x02
+#define MAX77620_REG_CNFG1_32K			0x03
+#define MAX77620_REG_CNFGBBC			0x04
+#define MAX77620_REG_IRQTOP			0x05
+#define MAX77620_REG_INTLBT			0x06
+#define MAX77620_REG_IRQSD			0x07
+#define MAX77620_REG_IRQ_LVL2_L0_7		0x08
+#define MAX77620_REG_IRQ_LVL2_L8		0x09
+#define MAX77620_REG_IRQ_LVL2_GPIO		0x0A
+#define MAX77620_REG_ONOFFIRQ			0x0B
+#define MAX77620_REG_NVERC			0x0C
+#define MAX77620_REG_IRQTOPM			0x0D
+#define MAX77620_REG_INTENLBT			0x0E
+#define MAX77620_REG_IRQMASKSD			0x0F
+#define MAX77620_REG_IRQ_MSK_L0_7		0x10
+#define MAX77620_REG_IRQ_MSK_L8			0x11
+#define MAX77620_REG_ONOFFIRQM			0x12
+#define MAX77620_REG_STATLBT			0x13
+#define MAX77620_REG_STATSD			0x14
+#define MAX77620_REG_ONOFFSTAT			0x15
+
+/* SD and LDO Registers */
+#define MAX77620_REG_SD0			0x16
+#define MAX77620_REG_SD1			0x17
+#define MAX77620_REG_SD2			0x18
+#define MAX77620_REG_SD3			0x19
+#define MAX77620_REG_SD4			0x1A
+#define MAX77620_REG_DVSSD0			0x1B
+#define MAX77620_REG_DVSSD1			0x1C
+#define MAX77620_REG_SD0_CFG			0x1D
+#define MAX77620_REG_SD1_CFG			0x1E
+#define MAX77620_REG_SD2_CFG			0x1F
+#define MAX77620_REG_SD3_CFG			0x20
+#define MAX77620_REG_SD4_CFG			0x21
+#define MAX77620_REG_SD_CFG2			0x22
+#define MAX77620_REG_LDO0_CFG			0x23
+#define MAX77620_REG_LDO0_CFG2			0x24
+#define MAX77620_REG_LDO1_CFG			0x25
+#define MAX77620_REG_LDO1_CFG2			0x26
+#define MAX77620_REG_LDO2_CFG			0x27
+#define MAX77620_REG_LDO2_CFG2			0x28
+#define MAX77620_REG_LDO3_CFG			0x29
+#define MAX77620_REG_LDO3_CFG2			0x2A
+#define MAX77620_REG_LDO4_CFG			0x2B
+#define MAX77620_REG_LDO4_CFG2			0x2C
+#define MAX77620_REG_LDO5_CFG			0x2D
+#define MAX77620_REG_LDO5_CFG2			0x2E
+#define MAX77620_REG_LDO6_CFG			0x2F
+#define MAX77620_REG_LDO6_CFG2			0x30
+#define MAX77620_REG_LDO7_CFG			0x31
+#define MAX77620_REG_LDO7_CFG2			0x32
+#define MAX77620_REG_LDO8_CFG			0x33
+#define MAX77620_REG_LDO8_CFG2			0x34
+#define MAX77620_REG_LDO_CFG3			0x35
+
+#define MAX77620_LDO_SLEW_RATE_MASK		0x1
+
+/* LDO Configuration 3 */
+#define MAX77620_TRACK4_MASK			BIT(5)
+#define MAX77620_TRACK4_SHIFT			5
+
+/* Voltage */
+#define MAX77620_SDX_VOLT_MASK			0xFF
+#define MAX77620_SD0_VOLT_MASK			0x3F
+#define MAX77620_SD1_VOLT_MASK			0x7F
+#define MAX77620_LDO_VOLT_MASK			0x3F
+
+#define MAX77620_REG_GPIO0			0x36
+#define MAX77620_REG_GPIO1			0x37
+#define MAX77620_REG_GPIO2			0x38
+#define MAX77620_REG_GPIO3			0x39
+#define MAX77620_REG_GPIO4			0x3A
+#define MAX77620_REG_GPIO5			0x3B
+#define MAX77620_REG_GPIO6			0x3C
+#define MAX77620_REG_GPIO7			0x3D
+#define MAX77620_REG_PUE_GPIO			0x3E
+#define MAX77620_REG_PDE_GPIO			0x3F
+#define MAX77620_REG_AME_GPIO			0x40
+#define MAX77620_REG_ONOFFCNFG1			0x41
+#define MAX77620_REG_ONOFFCNFG2			0x42
+
+/* FPS Registers */
+#define MAX77620_REG_FPS_CFG0			0x43
+#define MAX77620_REG_FPS_CFG1			0x44
+#define MAX77620_REG_FPS_CFG2			0x45
+#define MAX77620_REG_FPS_LDO0			0x46
+#define MAX77620_REG_FPS_LDO1			0x47
+#define MAX77620_REG_FPS_LDO2			0x48
+#define MAX77620_REG_FPS_LDO3			0x49
+#define MAX77620_REG_FPS_LDO4			0x4A
+#define MAX77620_REG_FPS_LDO5			0x4B
+#define MAX77620_REG_FPS_LDO6			0x4C
+#define MAX77620_REG_FPS_LDO7			0x4D
+#define MAX77620_REG_FPS_LDO8			0x4E
+#define MAX77620_REG_FPS_SD0			0x4F
+#define MAX77620_REG_FPS_SD1			0x50
+#define MAX77620_REG_FPS_SD2			0x51
+#define MAX77620_REG_FPS_SD3			0x52
+#define MAX77620_REG_FPS_SD4			0x53
+#define MAX77620_REG_FPS_NONE			0
+
+#define MAX77620_FPS_SRC_MASK			0xC0
+#define MAX77620_FPS_SRC_SHIFT			6
+#define MAX77620_FPS_PU_PERIOD_MASK		0x38
+#define MAX77620_FPS_PU_PERIOD_SHIFT		3
+#define MAX77620_FPS_PD_PERIOD_MASK		0x07
+#define MAX77620_FPS_PD_PERIOD_SHIFT		0
+#define MAX77620_FPS_TIME_PERIOD_MASK		0x38
+#define MAX77620_FPS_TIME_PERIOD_SHIFT		3
+#define MAX77620_FPS_EN_SRC_MASK		0x06
+#define MAX77620_FPS_EN_SRC_SHIFT		1
+#define MAX77620_FPS_ENFPS_SW_MASK		0x01
+#define MAX77620_FPS_ENFPS_SW			0x01
+
+/* Minimum and maximum FPS period time (in microseconds) are
+ * different for MAX77620 and Max20024.
+ */
+#define MAX77620_FPS_PERIOD_MIN_US		40
+#define MAX20024_FPS_PERIOD_MIN_US		20
+
+#define MAX77620_FPS_PERIOD_MAX_US		2560
+#define MAX20024_FPS_PERIOD_MAX_US		5120
+
+#define MAX77620_REG_FPS_GPIO1			0x54
+#define MAX77620_REG_FPS_GPIO2			0x55
+#define MAX77620_REG_FPS_GPIO3			0x56
+#define MAX77620_REG_FPS_RSO			0x57
+#define MAX77620_REG_CID0			0x58
+#define MAX77620_REG_CID1			0x59
+#define MAX77620_REG_CID2			0x5A
+#define MAX77620_REG_CID3			0x5B
+#define MAX77620_REG_CID4			0x5C
+#define MAX77620_REG_CID5			0x5D
+
+#define MAX77620_REG_DVSSD4			0x5E
+#define MAX20024_REG_MAX_ADD			0x70
+
+#define MAX77620_CID_DIDM_MASK			0xF0
+#define MAX77620_CID_DIDM_SHIFT			4
+
+/* CNCG2SD */
+#define MAX77620_SD_CNF2_ROVS_EN_SD1		BIT(1)
+#define MAX77620_SD_CNF2_ROVS_EN_SD0		BIT(2)
+
+/* Device Identification Metal */
+#define MAX77620_CID5_DIDM(n)			(((n) >> 4) & 0xF)
+/* Device Indentification OTP */
+#define MAX77620_CID5_DIDO(n)			((n) & 0xF)
+
+/* SD CNFG1 */
+#define MAX77620_SD_SR_MASK			0xC0
+#define MAX77620_SD_SR_SHIFT			6
+#define MAX77620_SD_POWER_MODE_MASK		0x30
+#define MAX77620_SD_POWER_MODE_SHIFT		4
+#define MAX77620_SD_CFG1_ADE_MASK		BIT(3)
+#define MAX77620_SD_CFG1_ADE_DISABLE		0
+#define MAX77620_SD_CFG1_ADE_ENABLE		BIT(3)
+#define MAX77620_SD_FPWM_MASK			0x04
+#define MAX77620_SD_FPWM_SHIFT			2
+#define MAX77620_SD_FSRADE_MASK			0x01
+#define MAX77620_SD_FSRADE_SHIFT		0
+#define MAX77620_SD_CFG1_FPWM_SD_MASK		BIT(2)
+#define MAX77620_SD_CFG1_FPWM_SD_SKIP		0
+#define MAX77620_SD_CFG1_FPWM_SD_FPWM		BIT(2)
+#define MAX77620_SD_CFG1_FSRADE_SD_MASK		BIT(0)
+#define MAX77620_SD_CFG1_FSRADE_SD_DISABLE	0
+#define MAX77620_SD_CFG1_FSRADE_SD_ENABLE	BIT(0)
+
+/* LDO_CNFG2 */
+#define MAX77620_LDO_POWER_MODE_MASK		0xC0
+#define MAX77620_LDO_POWER_MODE_SHIFT		6
+#define MAX77620_LDO_CFG2_ADE_MASK		BIT(1)
+#define MAX77620_LDO_CFG2_ADE_DISABLE		0
+#define MAX77620_LDO_CFG2_ADE_ENABLE		BIT(1)
+#define MAX77620_LDO_CFG2_SS_MASK		BIT(0)
+#define MAX77620_LDO_CFG2_SS_FAST		BIT(0)
+#define MAX77620_LDO_CFG2_SS_SLOW		0
+
+#define MAX77620_IRQ_TOP_GLBL_MASK		BIT(7)
+#define MAX77620_IRQ_TOP_SD_MASK		BIT(6)
+#define MAX77620_IRQ_TOP_LDO_MASK		BIT(5)
+#define MAX77620_IRQ_TOP_GPIO_MASK		BIT(4)
+#define MAX77620_IRQ_TOP_RTC_MASK		BIT(3)
+#define MAX77620_IRQ_TOP_32K_MASK		BIT(2)
+#define MAX77620_IRQ_TOP_ONOFF_MASK		BIT(1)
+
+#define MAX77620_IRQ_LBM_MASK			BIT(3)
+#define MAX77620_IRQ_TJALRM1_MASK		BIT(2)
+#define MAX77620_IRQ_TJALRM2_MASK		BIT(1)
+
+#define MAX77620_PWR_I2C_ADDR			0x3c
+#define MAX77620_RTC_I2C_ADDR			0x68
+
+#define MAX77620_CNFG_GPIO_DRV_MASK		BIT(0)
+#define MAX77620_CNFG_GPIO_DRV_PUSHPULL		BIT(0)
+#define MAX77620_CNFG_GPIO_DRV_OPENDRAIN	0
+#define MAX77620_CNFG_GPIO_DIR_MASK		BIT(1)
+#define MAX77620_CNFG_GPIO_DIR_INPUT		BIT(1)
+#define MAX77620_CNFG_GPIO_DIR_OUTPUT		0
+#define MAX77620_CNFG_GPIO_INPUT_VAL_MASK	BIT(2)
+#define MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK	BIT(3)
+#define MAX77620_CNFG_GPIO_OUTPUT_VAL_HIGH	BIT(3)
+#define MAX77620_CNFG_GPIO_OUTPUT_VAL_LOW	0
+#define MAX77620_CNFG_GPIO_INT_MASK		(0x3 << 4)
+#define MAX77620_CNFG_GPIO_INT_FALLING		BIT(4)
+#define MAX77620_CNFG_GPIO_INT_RISING		BIT(5)
+#define MAX77620_CNFG_GPIO_DBNC_MASK		(0x3 << 6)
+#define MAX77620_CNFG_GPIO_DBNC_None		(0x0 << 6)
+#define MAX77620_CNFG_GPIO_DBNC_8ms		(0x1 << 6)
+#define MAX77620_CNFG_GPIO_DBNC_16ms		(0x2 << 6)
+#define MAX77620_CNFG_GPIO_DBNC_32ms		(0x3 << 6)
+
+#define MAX77620_IRQ_LVL2_GPIO_EDGE0		BIT(0)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE1		BIT(1)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE2		BIT(2)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE3		BIT(3)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE4		BIT(4)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE5		BIT(5)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE6		BIT(6)
+#define MAX77620_IRQ_LVL2_GPIO_EDGE7		BIT(7)
+
+#define MAX77620_CNFG1_32K_OUT0_EN		BIT(2)
+
+#define MAX77620_ONOFFCNFG1_SFT_RST		BIT(7)
+#define MAX77620_ONOFFCNFG1_MRT_MASK		0x38
+#define MAX77620_ONOFFCNFG1_MRT_SHIFT		0x3
+#define MAX77620_ONOFFCNFG1_SLPEN		BIT(2)
+#define MAX77620_ONOFFCNFG1_PWR_OFF		BIT(1)
+#define MAX20024_ONOFFCNFG1_CLRSE		0x18
+
+#define MAX77620_ONOFFCNFG2_SFT_RST_WK		BIT(7)
+#define MAX77620_ONOFFCNFG2_WD_RST_WK		BIT(6)
+#define MAX77620_ONOFFCNFG2_SLP_LPM_MSK		BIT(5)
+#define MAX77620_ONOFFCNFG2_WK_ALARM1		BIT(2)
+#define MAX77620_ONOFFCNFG2_WK_EN0		BIT(0)
+
+#define MAX77620_GLBLM_MASK			BIT(0)
+
+#define MAX77620_WDTC_MASK			0x3
+#define MAX77620_WDTOFFC			BIT(4)
+#define MAX77620_WDTSLPC			BIT(3)
+#define MAX77620_WDTEN				BIT(2)
+
+#define MAX77620_TWD_MASK			0x3
+#define MAX77620_TWD_2s				0x0
+#define MAX77620_TWD_16s			0x1
+#define MAX77620_TWD_64s			0x2
+#define MAX77620_TWD_128s			0x3
+
+#define MAX77620_CNFGGLBL1_LBDAC_EN		BIT(7)
+#define MAX77620_CNFGGLBL1_MPPLD		BIT(6)
+#define MAX77620_CNFGGLBL1_LBHYST		(BIT(5) | BIT(4))
+#define MAX77620_CNFGGLBL1_LBDAC		0x0E
+#define MAX77620_CNFGGLBL1_LBRSTEN		BIT(0)
+
+/* CNFG BBC registers */
+#define MAX77620_CNFGBBC_ENABLE			BIT(0)
+#define MAX77620_CNFGBBC_CURRENT_MASK		0x06
+#define MAX77620_CNFGBBC_CURRENT_SHIFT		1
+#define MAX77620_CNFGBBC_VOLTAGE_MASK		0x18
+#define MAX77620_CNFGBBC_VOLTAGE_SHIFT		3
+#define MAX77620_CNFGBBC_LOW_CURRENT_DISABLE	BIT(5)
+#define MAX77620_CNFGBBC_RESISTOR_MASK		0xC0
+#define MAX77620_CNFGBBC_RESISTOR_SHIFT		6
+
+#define MAX77620_FPS_COUNT			3
+
+/* Interrupts */
+enum {
+	MAX77620_IRQ_TOP_GLBL,		/* Low-Battery */
+	MAX77620_IRQ_TOP_SD,		/* SD power fail */
+	MAX77620_IRQ_TOP_LDO,		/* LDO power fail */
+	MAX77620_IRQ_TOP_GPIO,		/* TOP GPIO internal int to MAX77620 */
+	MAX77620_IRQ_TOP_RTC,		/* RTC */
+	MAX77620_IRQ_TOP_32K,		/* 32kHz oscillator */
+	MAX77620_IRQ_TOP_ONOFF,		/* ON/OFF oscillator */
+	MAX77620_IRQ_LBT_MBATLOW,	/* Thermal alarm status, > 120C */
+	MAX77620_IRQ_LBT_TJALRM1,	/* Thermal alarm status, > 120C */
+	MAX77620_IRQ_LBT_TJALRM2,	/* Thermal alarm status, > 140C */
+};
+
+/* GPIOs */
+enum {
+	MAX77620_GPIO0,
+	MAX77620_GPIO1,
+	MAX77620_GPIO2,
+	MAX77620_GPIO3,
+	MAX77620_GPIO4,
+	MAX77620_GPIO5,
+	MAX77620_GPIO6,
+	MAX77620_GPIO7,
+	MAX77620_GPIO_NR,
+};
+
+/* FPS Source */
+enum max77620_fps_src {
+	MAX77620_FPS_SRC_0,
+	MAX77620_FPS_SRC_1,
+	MAX77620_FPS_SRC_2,
+	MAX77620_FPS_SRC_NONE,
+	MAX77620_FPS_SRC_DEF,
+};
+
+enum max77620_chip_id {
+	MAX77620,
+	MAX20024,
+};
+
+struct max77620_chip {
+	struct device *dev;
+	struct regmap *rmap;
+
+	int chip_irq;
+	int irq_base;
+
+	/* chip id */
+	enum max77620_chip_id chip_id;
+
+	bool sleep_enable;
+	bool enable_global_lpm;
+	int shutdown_fps_period[MAX77620_FPS_COUNT];
+	int suspend_fps_period[MAX77620_FPS_COUNT];
+
+	struct regmap_irq_chip_data *top_irq_data;
+	struct regmap_irq_chip_data *gpio_irq_data;
+};
+
+#endif /* _MFD_MAX77620_H_ */