src/kernel/linux/v4.19/drivers/gpio/gpio-pmic-eic-sprd.c - T800 - Gitiles

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2018 Spreadtrum Communications Inc.
  * Copyright (C) 2018 Linaro Ltd.
  */

 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>

 /* EIC registers definition */
 #define SPRD_PMIC_EIC_DATA		0x0
 #define SPRD_PMIC_EIC_DMSK		0x4
 #define SPRD_PMIC_EIC_IEV		0x14
 #define SPRD_PMIC_EIC_IE		0x18
 #define SPRD_PMIC_EIC_RIS		0x1c
 #define SPRD_PMIC_EIC_MIS		0x20
 #define SPRD_PMIC_EIC_IC		0x24
 #define SPRD_PMIC_EIC_TRIG		0x28
 #define SPRD_PMIC_EIC_CTRL0		0x40

 /*
  * The PMIC EIC controller only has one bank, and each bank now can contain
  * 16 EICs.
  */
 #define SPRD_PMIC_EIC_PER_BANK_NR	16
 #define SPRD_PMIC_EIC_NR		SPRD_PMIC_EIC_PER_BANK_NR
 #define SPRD_PMIC_EIC_DATA_MASK		GENMASK(15, 0)
 #define SPRD_PMIC_EIC_BIT(x)		((x) & (SPRD_PMIC_EIC_PER_BANK_NR - 1))
 #define SPRD_PMIC_EIC_DBNC_MASK		GENMASK(11, 0)

 /*
  * These registers are modified under the irq bus lock and cached to avoid
  * unnecessary writes in bus_sync_unlock.
  */
 enum {
 	REG_IEV,
 	REG_IE,
 	REG_TRIG,
 	CACHE_NR_REGS
 };

 /**
  * struct sprd_pmic_eic - PMIC EIC controller
  * @chip: the gpio_chip structure.
  * @intc: the irq_chip structure.
  * @regmap: the regmap from the parent device.
  * @offset: the EIC controller's offset address of the PMIC.
  * @reg: the array to cache the EIC registers.
  * @buslock: for bus lock/sync and unlock.
  * @irq: the interrupt number of the PMIC EIC conteroller.
  */
 struct sprd_pmic_eic {
 	struct gpio_chip chip;
 	struct irq_chip intc;
 	struct regmap *map;
 	u32 offset;
 	u8 reg[CACHE_NR_REGS];
 	struct mutex buslock;
 	int irq;
 };

 static void sprd_pmic_eic_update(struct gpio_chip *chip, unsigned int offset,
 				 u16 reg, unsigned int val)
 {
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
 	u32 shift = SPRD_PMIC_EIC_BIT(offset);

 	regmap_update_bits(pmic_eic->map, pmic_eic->offset + reg,
 			   BIT(shift), val << shift);
 }

 static int sprd_pmic_eic_read(struct gpio_chip *chip, unsigned int offset,
 			      u16 reg)
 {
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
 	u32 value;
 	int ret;

 	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
 	if (ret)
 		return ret;

 	return !!(value & BIT(SPRD_PMIC_EIC_BIT(offset)));
 }

 static int sprd_pmic_eic_request(struct gpio_chip *chip, unsigned int offset)
 {
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 1);
 	return 0;
 }

 static void sprd_pmic_eic_free(struct gpio_chip *chip, unsigned int offset)
 {
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 0);
 }

 static int sprd_pmic_eic_get(struct gpio_chip *chip, unsigned int offset)
 {
 	return sprd_pmic_eic_read(chip, offset, SPRD_PMIC_EIC_DATA);
 }

 static int sprd_pmic_eic_direction_input(struct gpio_chip *chip,
 					 unsigned int offset)
 {
 	/* EICs are always input, nothing need to do here. */
 	return 0;
 }

 static void sprd_pmic_eic_set(struct gpio_chip *chip, unsigned int offset,
 			      int value)
 {
 	/* EICs are always input, nothing need to do here. */
 }

 static int sprd_pmic_eic_set_debounce(struct gpio_chip *chip,
 				      unsigned int offset,
 				      unsigned int debounce)
 {
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
 	u32 reg, value;
 	int ret;

 	reg = SPRD_PMIC_EIC_CTRL0 + SPRD_PMIC_EIC_BIT(offset) * 0x4;
 	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
 	if (ret)
 		return ret;

 	value &= ~SPRD_PMIC_EIC_DBNC_MASK;
 	value |= (debounce / 1000) & SPRD_PMIC_EIC_DBNC_MASK;
 	return regmap_write(pmic_eic->map, pmic_eic->offset + reg, value);
 }

 static int sprd_pmic_eic_set_config(struct gpio_chip *chip, unsigned int offset,
 				    unsigned long config)
 {
 	unsigned long param = pinconf_to_config_param(config);
 	u32 arg = pinconf_to_config_argument(config);

 	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
 		return sprd_pmic_eic_set_debounce(chip, offset, arg);

 	return -ENOTSUPP;
 }

 static void sprd_pmic_eic_irq_mask(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

 	pmic_eic->reg[REG_IE] = 0;
 	pmic_eic->reg[REG_TRIG] = 0;
 }

 static void sprd_pmic_eic_irq_unmask(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

 	pmic_eic->reg[REG_IE] = 1;
 	pmic_eic->reg[REG_TRIG] = 1;
 }

 static int sprd_pmic_eic_irq_set_type(struct irq_data *data,
 				      unsigned int flow_type)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

 	switch (flow_type) {
 	case IRQ_TYPE_LEVEL_HIGH:
 		pmic_eic->reg[REG_IEV] = 1;
 		break;
 	case IRQ_TYPE_LEVEL_LOW:
 		pmic_eic->reg[REG_IEV] = 0;
 		break;
 	case IRQ_TYPE_EDGE_RISING:
 	case IRQ_TYPE_EDGE_FALLING:
 	case IRQ_TYPE_EDGE_BOTH:
 		/*
 		 * Will set the trigger level according to current EIC level
 		 * in irq_bus_sync_unlock() interface, so here nothing to do.
 		 */
 		break;
 	default:
 		return -ENOTSUPP;
 	}

 	return 0;
 }

 static void sprd_pmic_eic_bus_lock(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

 	mutex_lock(&pmic_eic->buslock);
 }

 static void sprd_pmic_eic_bus_sync_unlock(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
 	u32 trigger = irqd_get_trigger_type(data);
 	u32 offset = irqd_to_hwirq(data);
 	int state;

 	/* Set irq type */
 	if (trigger & IRQ_TYPE_EDGE_BOTH) {
 		state = sprd_pmic_eic_get(chip, offset);
 		if (state)
 			sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
 		else
 			sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
 	} else {
 		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV,
 				     pmic_eic->reg[REG_IEV]);
 	}

 	/* Set irq unmask */
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE,
 			     pmic_eic->reg[REG_IE]);
 	/* Generate trigger start pulse for debounce EIC */
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG,
 			     pmic_eic->reg[REG_TRIG]);

 	mutex_unlock(&pmic_eic->buslock);
 }

 static void sprd_pmic_eic_toggle_trigger(struct gpio_chip *chip,
 					 unsigned int irq, unsigned int offset)
 {
 	u32 trigger = irq_get_trigger_type(irq);
 	int state, post_state;

 	if (!(trigger & IRQ_TYPE_EDGE_BOTH))
 		return;

 	state = sprd_pmic_eic_get(chip, offset);
 retry:
 	if (state)
 		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
 	else
 		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);

 	post_state = sprd_pmic_eic_get(chip, offset);
 	if (state != post_state) {
 		dev_warn(chip->parent, "PMIC EIC level was changed.\n");
 		state = post_state;
 		goto retry;
 	}

 	/* Set irq unmask */
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE, 1);
 	/* Generate trigger start pulse for debounce EIC */
 	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG, 1);
 }

 static irqreturn_t sprd_pmic_eic_irq_handler(int irq, void *data)
 {
 	struct sprd_pmic_eic *pmic_eic = data;
 	struct gpio_chip *chip = &pmic_eic->chip;
 	unsigned long status;
 	u32 n, girq, val;
 	int ret;

 	ret = regmap_read(pmic_eic->map, pmic_eic->offset + SPRD_PMIC_EIC_MIS,
 			  &val);
 	if (ret)
 		return IRQ_RETVAL(ret);

 	status = val & SPRD_PMIC_EIC_DATA_MASK;

 	for_each_set_bit(n, &status, chip->ngpio) {
 		/* Clear the interrupt */
 		sprd_pmic_eic_update(chip, n, SPRD_PMIC_EIC_IC, 1);

 		girq = irq_find_mapping(chip->irq.domain, n);
 		handle_nested_irq(girq);

 		/*
 		 * The PMIC EIC can only support level trigger, so we can
 		 * toggle the level trigger to emulate the edge trigger.
 		 */
 		sprd_pmic_eic_toggle_trigger(chip, girq, n);
 	}

 	return IRQ_HANDLED;
 }

 static int sprd_pmic_eic_probe(struct platform_device *pdev)
 {
 	struct gpio_irq_chip *irq;
 	struct sprd_pmic_eic *pmic_eic;
 	int ret;

 	pmic_eic = devm_kzalloc(&pdev->dev, sizeof(*pmic_eic), GFP_KERNEL);
 	if (!pmic_eic)
 		return -ENOMEM;

 	mutex_init(&pmic_eic->buslock);

 	pmic_eic->irq = platform_get_irq(pdev, 0);
 	if (pmic_eic->irq < 0) {
 		dev_err(&pdev->dev, "Failed to get PMIC EIC interrupt.\n");
 		return pmic_eic->irq;
 	}

 	pmic_eic->map = dev_get_regmap(pdev->dev.parent, NULL);
 	if (!pmic_eic->map)
 		return -ENODEV;

 	ret = of_property_read_u32(pdev->dev.of_node, "reg", &pmic_eic->offset);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to get PMIC EIC base address.\n");
 		return ret;
 	}

 	ret = devm_request_threaded_irq(&pdev->dev, pmic_eic->irq, NULL,
 					sprd_pmic_eic_irq_handler,
 					IRQF_TRIGGER_LOW |
 					IRQF_ONESHOT | IRQF_NO_SUSPEND,
 					dev_name(&pdev->dev), pmic_eic);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to request PMIC EIC IRQ.\n");
 		return ret;
 	}

 	pmic_eic->chip.label = dev_name(&pdev->dev);
 	pmic_eic->chip.ngpio = SPRD_PMIC_EIC_NR;
 	pmic_eic->chip.base = -1;
 	pmic_eic->chip.parent = &pdev->dev;
 	pmic_eic->chip.of_node = pdev->dev.of_node;
 	pmic_eic->chip.direction_input = sprd_pmic_eic_direction_input;
 	pmic_eic->chip.request = sprd_pmic_eic_request;
 	pmic_eic->chip.free = sprd_pmic_eic_free;
 	pmic_eic->chip.set_config = sprd_pmic_eic_set_config;
 	pmic_eic->chip.set = sprd_pmic_eic_set;
 	pmic_eic->chip.get = sprd_pmic_eic_get;

 	pmic_eic->intc.name = dev_name(&pdev->dev);
 	pmic_eic->intc.irq_mask = sprd_pmic_eic_irq_mask;
 	pmic_eic->intc.irq_unmask = sprd_pmic_eic_irq_unmask;
 	pmic_eic->intc.irq_set_type = sprd_pmic_eic_irq_set_type;
 	pmic_eic->intc.irq_bus_lock = sprd_pmic_eic_bus_lock;
 	pmic_eic->intc.irq_bus_sync_unlock = sprd_pmic_eic_bus_sync_unlock;
 	pmic_eic->intc.flags = IRQCHIP_SKIP_SET_WAKE;

 	irq = &pmic_eic->chip.irq;
 	irq->chip = &pmic_eic->intc;
 	irq->threaded = true;

 	ret = devm_gpiochip_add_data(&pdev->dev, &pmic_eic->chip, pmic_eic);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
 		return ret;
 	}

 	platform_set_drvdata(pdev, pmic_eic);
 	return 0;
 }

 static const struct of_device_id sprd_pmic_eic_of_match[] = {
 	{ .compatible = "sprd,sc27xx-eic", },
 	{ /* end of list */ }
 };
 MODULE_DEVICE_TABLE(of, sprd_pmic_eic_of_match);

 static struct platform_driver sprd_pmic_eic_driver = {
 	.probe = sprd_pmic_eic_probe,
 	.driver = {
 		.name = "sprd-pmic-eic",
 		.of_match_table	= sprd_pmic_eic_of_match,
 	},
 };

 module_platform_driver(sprd_pmic_eic_driver);

 MODULE_DESCRIPTION("Spreadtrum PMIC EIC driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Copyright (C) 2018 Spreadtrum Communications Inc.
	* Copyright (C) 2018 Linaro Ltd.
	*/

	#include <linux/gpio/driver.h>
	#include <linux/interrupt.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of_device.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>

	/* EIC registers definition */
	#define SPRD_PMIC_EIC_DATA 0x0
	#define SPRD_PMIC_EIC_DMSK 0x4
	#define SPRD_PMIC_EIC_IEV 0x14
	#define SPRD_PMIC_EIC_IE 0x18
	#define SPRD_PMIC_EIC_RIS 0x1c
	#define SPRD_PMIC_EIC_MIS 0x20
	#define SPRD_PMIC_EIC_IC 0x24
	#define SPRD_PMIC_EIC_TRIG 0x28
	#define SPRD_PMIC_EIC_CTRL0 0x40

	/*
	* The PMIC EIC controller only has one bank, and each bank now can contain
	* 16 EICs.
	*/
	#define SPRD_PMIC_EIC_PER_BANK_NR 16
	#define SPRD_PMIC_EIC_NR SPRD_PMIC_EIC_PER_BANK_NR
	#define SPRD_PMIC_EIC_DATA_MASK GENMASK(15, 0)
	#define SPRD_PMIC_EIC_BIT(x) ((x) & (SPRD_PMIC_EIC_PER_BANK_NR - 1))
	#define SPRD_PMIC_EIC_DBNC_MASK GENMASK(11, 0)

	/*
	* These registers are modified under the irq bus lock and cached to avoid
	* unnecessary writes in bus_sync_unlock.
	*/
	enum {
	REG_IEV,
	REG_IE,
	REG_TRIG,
	CACHE_NR_REGS
	};

	/**
	* struct sprd_pmic_eic - PMIC EIC controller
	* @chip: the gpio_chip structure.
	* @intc: the irq_chip structure.
	* @regmap: the regmap from the parent device.
	* @offset: the EIC controller's offset address of the PMIC.
	* @reg: the array to cache the EIC registers.
	* @buslock: for bus lock/sync and unlock.
	* @irq: the interrupt number of the PMIC EIC conteroller.
	*/
	struct sprd_pmic_eic {
	struct gpio_chip chip;
	struct irq_chip intc;
	struct regmap *map;
	u32 offset;
	u8 reg[CACHE_NR_REGS];
	struct mutex buslock;
	int irq;
	};

	static void sprd_pmic_eic_update(struct gpio_chip *chip, unsigned int offset,
	u16 reg, unsigned int val)
	{
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
	u32 shift = SPRD_PMIC_EIC_BIT(offset);

	regmap_update_bits(pmic_eic->map, pmic_eic->offset + reg,
	BIT(shift), val << shift);
	}

	static int sprd_pmic_eic_read(struct gpio_chip *chip, unsigned int offset,
	u16 reg)
	{
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
	u32 value;
	int ret;

	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
	if (ret)
	return ret;

	return !!(value & BIT(SPRD_PMIC_EIC_BIT(offset)));
	}

	static int sprd_pmic_eic_request(struct gpio_chip *chip, unsigned int offset)
	{
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 1);
	return 0;
	}

	static void sprd_pmic_eic_free(struct gpio_chip *chip, unsigned int offset)
	{
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 0);
	}

	static int sprd_pmic_eic_get(struct gpio_chip *chip, unsigned int offset)
	{
	return sprd_pmic_eic_read(chip, offset, SPRD_PMIC_EIC_DATA);
	}

	static int sprd_pmic_eic_direction_input(struct gpio_chip *chip,
	unsigned int offset)
	{
	/* EICs are always input, nothing need to do here. */
	return 0;
	}

	static void sprd_pmic_eic_set(struct gpio_chip *chip, unsigned int offset,
	int value)
	{
	/* EICs are always input, nothing need to do here. */
	}

	static int sprd_pmic_eic_set_debounce(struct gpio_chip *chip,
	unsigned int offset,
	unsigned int debounce)
	{
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
	u32 reg, value;
	int ret;

	reg = SPRD_PMIC_EIC_CTRL0 + SPRD_PMIC_EIC_BIT(offset) * 0x4;
	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
	if (ret)
	return ret;

	value &= ~SPRD_PMIC_EIC_DBNC_MASK;
	value \|= (debounce / 1000) & SPRD_PMIC_EIC_DBNC_MASK;
	return regmap_write(pmic_eic->map, pmic_eic->offset + reg, value);
	}

	static int sprd_pmic_eic_set_config(struct gpio_chip *chip, unsigned int offset,
	unsigned long config)
	{
	unsigned long param = pinconf_to_config_param(config);
	u32 arg = pinconf_to_config_argument(config);

	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
	return sprd_pmic_eic_set_debounce(chip, offset, arg);

	return -ENOTSUPP;
	}

	static void sprd_pmic_eic_irq_mask(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

	pmic_eic->reg[REG_IE] = 0;
	pmic_eic->reg[REG_TRIG] = 0;
	}

	static void sprd_pmic_eic_irq_unmask(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

	pmic_eic->reg[REG_IE] = 1;
	pmic_eic->reg[REG_TRIG] = 1;
	}

	static int sprd_pmic_eic_irq_set_type(struct irq_data *data,
	unsigned int flow_type)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

	switch (flow_type) {
	case IRQ_TYPE_LEVEL_HIGH:
	pmic_eic->reg[REG_IEV] = 1;
	break;
	case IRQ_TYPE_LEVEL_LOW:
	pmic_eic->reg[REG_IEV] = 0;
	break;
	case IRQ_TYPE_EDGE_RISING:
	case IRQ_TYPE_EDGE_FALLING:
	case IRQ_TYPE_EDGE_BOTH:
	/*
	* Will set the trigger level according to current EIC level
	* in irq_bus_sync_unlock() interface, so here nothing to do.
	*/
	break;
	default:
	return -ENOTSUPP;
	}

	return 0;
	}

	static void sprd_pmic_eic_bus_lock(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);

	mutex_lock(&pmic_eic->buslock);
	}

	static void sprd_pmic_eic_bus_sync_unlock(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
	u32 trigger = irqd_get_trigger_type(data);
	u32 offset = irqd_to_hwirq(data);
	int state;

	/* Set irq type */
	if (trigger & IRQ_TYPE_EDGE_BOTH) {
	state = sprd_pmic_eic_get(chip, offset);
	if (state)
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
	else
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
	} else {
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV,
	pmic_eic->reg[REG_IEV]);
	}

	/* Set irq unmask */
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE,
	pmic_eic->reg[REG_IE]);
	/* Generate trigger start pulse for debounce EIC */
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG,
	pmic_eic->reg[REG_TRIG]);

	mutex_unlock(&pmic_eic->buslock);
	}

	static void sprd_pmic_eic_toggle_trigger(struct gpio_chip *chip,
	unsigned int irq, unsigned int offset)
	{
	u32 trigger = irq_get_trigger_type(irq);
	int state, post_state;

	if (!(trigger & IRQ_TYPE_EDGE_BOTH))
	return;

	state = sprd_pmic_eic_get(chip, offset);
	retry:
	if (state)
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
	else
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);

	post_state = sprd_pmic_eic_get(chip, offset);
	if (state != post_state) {
	dev_warn(chip->parent, "PMIC EIC level was changed.\n");
	state = post_state;
	goto retry;
	}

	/* Set irq unmask */
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE, 1);
	/* Generate trigger start pulse for debounce EIC */
	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG, 1);
	}

	static irqreturn_t sprd_pmic_eic_irq_handler(int irq, void *data)
	{
	struct sprd_pmic_eic *pmic_eic = data;
	struct gpio_chip *chip = &pmic_eic->chip;
	unsigned long status;
	u32 n, girq, val;
	int ret;

	ret = regmap_read(pmic_eic->map, pmic_eic->offset + SPRD_PMIC_EIC_MIS,
	&val);
	if (ret)
	return IRQ_RETVAL(ret);

	status = val & SPRD_PMIC_EIC_DATA_MASK;

	for_each_set_bit(n, &status, chip->ngpio) {
	/* Clear the interrupt */
	sprd_pmic_eic_update(chip, n, SPRD_PMIC_EIC_IC, 1);

	girq = irq_find_mapping(chip->irq.domain, n);
	handle_nested_irq(girq);

	/*
	* The PMIC EIC can only support level trigger, so we can
	* toggle the level trigger to emulate the edge trigger.
	*/
	sprd_pmic_eic_toggle_trigger(chip, girq, n);
	}

	return IRQ_HANDLED;
	}

	static int sprd_pmic_eic_probe(struct platform_device *pdev)
	{
	struct gpio_irq_chip *irq;
	struct sprd_pmic_eic *pmic_eic;
	int ret;

	pmic_eic = devm_kzalloc(&pdev->dev, sizeof(*pmic_eic), GFP_KERNEL);
	if (!pmic_eic)
	return -ENOMEM;

	mutex_init(&pmic_eic->buslock);

	pmic_eic->irq = platform_get_irq(pdev, 0);
	if (pmic_eic->irq < 0) {
	dev_err(&pdev->dev, "Failed to get PMIC EIC interrupt.\n");
	return pmic_eic->irq;
	}

	pmic_eic->map = dev_get_regmap(pdev->dev.parent, NULL);
	if (!pmic_eic->map)
	return -ENODEV;

	ret = of_property_read_u32(pdev->dev.of_node, "reg", &pmic_eic->offset);
	if (ret) {
	dev_err(&pdev->dev, "Failed to get PMIC EIC base address.\n");
	return ret;
	}

	ret = devm_request_threaded_irq(&pdev->dev, pmic_eic->irq, NULL,
	sprd_pmic_eic_irq_handler,
	IRQF_TRIGGER_LOW \|
	IRQF_ONESHOT \| IRQF_NO_SUSPEND,
	dev_name(&pdev->dev), pmic_eic);
	if (ret) {
	dev_err(&pdev->dev, "Failed to request PMIC EIC IRQ.\n");
	return ret;
	}

	pmic_eic->chip.label = dev_name(&pdev->dev);
	pmic_eic->chip.ngpio = SPRD_PMIC_EIC_NR;
	pmic_eic->chip.base = -1;
	pmic_eic->chip.parent = &pdev->dev;
	pmic_eic->chip.of_node = pdev->dev.of_node;
	pmic_eic->chip.direction_input = sprd_pmic_eic_direction_input;
	pmic_eic->chip.request = sprd_pmic_eic_request;
	pmic_eic->chip.free = sprd_pmic_eic_free;
	pmic_eic->chip.set_config = sprd_pmic_eic_set_config;
	pmic_eic->chip.set = sprd_pmic_eic_set;
	pmic_eic->chip.get = sprd_pmic_eic_get;

	pmic_eic->intc.name = dev_name(&pdev->dev);
	pmic_eic->intc.irq_mask = sprd_pmic_eic_irq_mask;
	pmic_eic->intc.irq_unmask = sprd_pmic_eic_irq_unmask;
	pmic_eic->intc.irq_set_type = sprd_pmic_eic_irq_set_type;
	pmic_eic->intc.irq_bus_lock = sprd_pmic_eic_bus_lock;
	pmic_eic->intc.irq_bus_sync_unlock = sprd_pmic_eic_bus_sync_unlock;
	pmic_eic->intc.flags = IRQCHIP_SKIP_SET_WAKE;

	irq = &pmic_eic->chip.irq;
	irq->chip = &pmic_eic->intc;
	irq->threaded = true;

	ret = devm_gpiochip_add_data(&pdev->dev, &pmic_eic->chip, pmic_eic);
	if (ret < 0) {
	dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
	return ret;
	}

	platform_set_drvdata(pdev, pmic_eic);
	return 0;
	}

	static const struct of_device_id sprd_pmic_eic_of_match[] = {
	{ .compatible = "sprd,sc27xx-eic", },
	{ /* end of list */ }
	};
	MODULE_DEVICE_TABLE(of, sprd_pmic_eic_of_match);

	static struct platform_driver sprd_pmic_eic_driver = {
	.probe = sprd_pmic_eic_probe,
	.driver = {
	.name = "sprd-pmic-eic",
	.of_match_table = sprd_pmic_eic_of_match,
	},
	};

	module_platform_driver(sprd_pmic_eic_driver);

	MODULE_DESCRIPTION("Spreadtrum PMIC EIC driver");
	MODULE_LICENSE("GPL v2");