drivers/gpio/gpio-crystalcove.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Intel Crystal Cove GPIO Driver
  *
  * Copyright (C) 2012, 2014 Intel Corporation. All rights reserved.
  *
  * Author: Yang, Bin <bin.yang@intel.com>
  */

 #include <linux/bitops.h>
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/mfd/intel_soc_pmic.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/seq_file.h>
 #include <linux/types.h>

 #define CRYSTALCOVE_GPIO_NUM	16
 #define CRYSTALCOVE_VGPIO_NUM	95

 #define UPDATE_IRQ_TYPE		BIT(0)
 #define UPDATE_IRQ_MASK		BIT(1)

 #define GPIO0IRQ		0x0b
 #define GPIO1IRQ		0x0c
 #define MGPIO0IRQS0		0x19
 #define MGPIO1IRQS0		0x1a
 #define MGPIO0IRQSX		0x1b
 #define MGPIO1IRQSX		0x1c
 #define GPIO0P0CTLO		0x2b
 #define GPIO0P0CTLI		0x33
 #define GPIO1P0CTLO		0x3b
 #define GPIO1P0CTLI		0x43
 #define GPIOPANELCTL		0x52

 #define CTLI_INTCNT_DIS		(0)
 #define CTLI_INTCNT_NE		(1 << 1)
 #define CTLI_INTCNT_PE		(2 << 1)
 #define CTLI_INTCNT_BE		(3 << 1)

 #define CTLO_DIR_IN		(0)
 #define CTLO_DIR_OUT		(1 << 5)

 #define CTLO_DRV_CMOS		(0)
 #define CTLO_DRV_OD		(1 << 4)

 #define CTLO_DRV_REN		(1 << 3)

 #define CTLO_RVAL_2KDW		(0)
 #define CTLO_RVAL_2KUP		(1 << 1)
 #define CTLO_RVAL_50KDW		(2 << 1)
 #define CTLO_RVAL_50KUP		(3 << 1)

 #define CTLO_INPUT_SET	(CTLO_DRV_CMOS | CTLO_DRV_REN | CTLO_RVAL_2KUP)
 #define CTLO_OUTPUT_SET	(CTLO_DIR_OUT | CTLO_INPUT_SET)

 enum ctrl_register {
 	CTRL_IN,
 	CTRL_OUT,
 };

 /**
  * struct crystalcove_gpio - Crystal Cove GPIO controller
  * @buslock: for bus lock/sync and unlock.
  * @chip: the abstract gpio_chip structure.
  * @regmap: the regmap from the parent device.
  * @update: pending IRQ setting update, to be written to the chip upon unlock.
  * @intcnt_value: the Interrupt Detect value to be written.
  * @set_irq_mask: true if the IRQ mask needs to be set, false to clear.
  */
 struct crystalcove_gpio {
 	struct mutex buslock; /* irq_bus_lock */
 	struct gpio_chip chip;
 	struct regmap *regmap;
 	int update;
 	int intcnt_value;
 	bool set_irq_mask;
 };

 static inline int to_reg(int gpio, enum ctrl_register reg_type)
 {
 	int reg;

 	if (gpio >= CRYSTALCOVE_GPIO_NUM) {
 		/*
 		 * Virtual GPIO called from ACPI, for now we only support
 		 * the panel ctl.
 		 */
 		switch (gpio) {
 		case 0x5e:
 			return GPIOPANELCTL;
 		default:
 			return -ENOTSUPP;
 		}
 	}

 	if (reg_type == CTRL_IN) {
 		if (gpio < 8)
 			reg = GPIO0P0CTLI;
 		else
 			reg = GPIO1P0CTLI;
 	} else {
 		if (gpio < 8)
 			reg = GPIO0P0CTLO;
 		else
 			reg = GPIO1P0CTLO;
 	}

 	return reg + gpio % 8;
 }

 static void crystalcove_update_irq_mask(struct crystalcove_gpio *cg, int gpio)
 {
 	u8 mirqs0 = gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0;
 	int mask = BIT(gpio % 8);

 	if (cg->set_irq_mask)
 		regmap_update_bits(cg->regmap, mirqs0, mask, mask);
 	else
 		regmap_update_bits(cg->regmap, mirqs0, mask, 0);
 }

 static void crystalcove_update_irq_ctrl(struct crystalcove_gpio *cg, int gpio)
 {
 	int reg = to_reg(gpio, CTRL_IN);

 	regmap_update_bits(cg->regmap, reg, CTLI_INTCNT_BE, cg->intcnt_value);
 }

 static int crystalcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
 	int reg = to_reg(gpio, CTRL_OUT);

 	if (reg < 0)
 		return 0;

 	return regmap_write(cg->regmap, reg, CTLO_INPUT_SET);
 }

 static int crystalcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio, int value)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
 	int reg = to_reg(gpio, CTRL_OUT);

 	if (reg < 0)
 		return 0;

 	return regmap_write(cg->regmap, reg, CTLO_OUTPUT_SET | value);
 }

 static int crystalcove_gpio_get(struct gpio_chip *chip, unsigned int gpio)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
 	unsigned int val;
 	int ret, reg = to_reg(gpio, CTRL_IN);

 	if (reg < 0)
 		return 0;

 	ret = regmap_read(cg->regmap, reg, &val);
 	if (ret)
 		return ret;

 	return val & 0x1;
 }

 static void crystalcove_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
 	int reg = to_reg(gpio, CTRL_OUT);

 	if (reg < 0)
 		return;

 	if (value)
 		regmap_update_bits(cg->regmap, reg, 1, 1);
 	else
 		regmap_update_bits(cg->regmap, reg, 1, 0);
 }

 static int crystalcove_irq_type(struct irq_data *data, unsigned int type)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));
 	irq_hw_number_t hwirq = irqd_to_hwirq(data);

 	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
 		return 0;

 	switch (type) {
 	case IRQ_TYPE_NONE:
 		cg->intcnt_value = CTLI_INTCNT_DIS;
 		break;
 	case IRQ_TYPE_EDGE_BOTH:
 		cg->intcnt_value = CTLI_INTCNT_BE;
 		break;
 	case IRQ_TYPE_EDGE_RISING:
 		cg->intcnt_value = CTLI_INTCNT_PE;
 		break;
 	case IRQ_TYPE_EDGE_FALLING:
 		cg->intcnt_value = CTLI_INTCNT_NE;
 		break;
 	default:
 		return -EINVAL;
 	}

 	cg->update |= UPDATE_IRQ_TYPE;

 	return 0;
 }

 static void crystalcove_bus_lock(struct irq_data *data)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));

 	mutex_lock(&cg->buslock);
 }

 static void crystalcove_bus_sync_unlock(struct irq_data *data)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));
 	irq_hw_number_t hwirq = irqd_to_hwirq(data);

 	if (cg->update & UPDATE_IRQ_TYPE)
 		crystalcove_update_irq_ctrl(cg, hwirq);
 	if (cg->update & UPDATE_IRQ_MASK)
 		crystalcove_update_irq_mask(cg, hwirq);
 	cg->update = 0;

 	mutex_unlock(&cg->buslock);
 }

 static void crystalcove_irq_unmask(struct irq_data *data)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
 	struct crystalcove_gpio *cg = gpiochip_get_data(gc);
 	irq_hw_number_t hwirq = irqd_to_hwirq(data);

 	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
 		return;

 	gpiochip_enable_irq(gc, hwirq);

 	cg->set_irq_mask = false;
 	cg->update |= UPDATE_IRQ_MASK;
 }

 static void crystalcove_irq_mask(struct irq_data *data)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
 	struct crystalcove_gpio *cg = gpiochip_get_data(gc);
 	irq_hw_number_t hwirq = irqd_to_hwirq(data);

 	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
 		return;

 	cg->set_irq_mask = true;
 	cg->update |= UPDATE_IRQ_MASK;

 	gpiochip_disable_irq(gc, hwirq);
 }

 static const struct irq_chip crystalcove_irqchip = {
 	.name			= "Crystal Cove",
 	.irq_mask		= crystalcove_irq_mask,
 	.irq_unmask		= crystalcove_irq_unmask,
 	.irq_set_type		= crystalcove_irq_type,
 	.irq_bus_lock		= crystalcove_bus_lock,
 	.irq_bus_sync_unlock	= crystalcove_bus_sync_unlock,
 	.flags			= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_IMMUTABLE,
 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };

 static irqreturn_t crystalcove_gpio_irq_handler(int irq, void *data)
 {
 	struct crystalcove_gpio *cg = data;
 	unsigned long pending;
 	unsigned int p0, p1;
 	int gpio;
 	unsigned int virq;

 	if (regmap_read(cg->regmap, GPIO0IRQ, &p0) ||
 	    regmap_read(cg->regmap, GPIO1IRQ, &p1))
 		return IRQ_NONE;

 	regmap_write(cg->regmap, GPIO0IRQ, p0);
 	regmap_write(cg->regmap, GPIO1IRQ, p1);

 	pending = p0 | p1 << 8;

 	for_each_set_bit(gpio, &pending, CRYSTALCOVE_GPIO_NUM) {
 		virq = irq_find_mapping(cg->chip.irq.domain, gpio);
 		handle_nested_irq(virq);
 	}

 	return IRQ_HANDLED;
 }

 static void crystalcove_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 {
 	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
 	int gpio, offset;
 	unsigned int ctlo, ctli, mirqs0, mirqsx, irq;

 	for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {
 		regmap_read(cg->regmap, to_reg(gpio, CTRL_OUT), &ctlo);
 		regmap_read(cg->regmap, to_reg(gpio, CTRL_IN), &ctli);
 		regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0,
 			    &mirqs0);
 		regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQSX : MGPIO1IRQSX,
 			    &mirqsx);
 		regmap_read(cg->regmap, gpio < 8 ? GPIO0IRQ : GPIO1IRQ,
 			    &irq);

 		offset = gpio % 8;
 		seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s %s\n",
 			   gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ",
 			   ctli & 0x1 ? "hi" : "lo",
 			   ctli & CTLI_INTCNT_NE ? "fall" : "    ",
 			   ctli & CTLI_INTCNT_PE ? "rise" : "    ",
 			   ctlo,
 			   mirqs0 & BIT(offset) ? "s0 mask  " : "s0 unmask",
 			   mirqsx & BIT(offset) ? "sx mask  " : "sx unmask",
 			   irq & BIT(offset) ? "pending" : "       ");
 	}
 }

 static int crystalcove_gpio_probe(struct platform_device *pdev)
 {
 	int irq = platform_get_irq(pdev, 0);
 	struct crystalcove_gpio *cg;
 	int retval;
 	struct device *dev = pdev->dev.parent;
 	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
 	struct gpio_irq_chip *girq;

 	if (irq < 0)
 		return irq;

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

 	mutex_init(&cg->buslock);
 	cg->chip.label = KBUILD_MODNAME;
 	cg->chip.direction_input = crystalcove_gpio_dir_in;
 	cg->chip.direction_output = crystalcove_gpio_dir_out;
 	cg->chip.get = crystalcove_gpio_get;
 	cg->chip.set = crystalcove_gpio_set;
 	cg->chip.base = -1;
 	cg->chip.ngpio = CRYSTALCOVE_VGPIO_NUM;
 	cg->chip.can_sleep = true;
 	cg->chip.parent = dev;
 	cg->chip.dbg_show = crystalcove_gpio_dbg_show;
 	cg->regmap = pmic->regmap;

 	girq = &cg->chip.irq;
 	gpio_irq_chip_set_chip(girq, &crystalcove_irqchip);
 	/* This will let us handle the parent IRQ in the driver */
 	girq->parent_handler = NULL;
 	girq->num_parents = 0;
 	girq->parents = NULL;
 	girq->default_type = IRQ_TYPE_NONE;
 	girq->handler = handle_simple_irq;
 	girq->threaded = true;

 	retval = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 					   crystalcove_gpio_irq_handler,
 					   IRQF_ONESHOT, KBUILD_MODNAME, cg);
 	if (retval) {
 		dev_warn(&pdev->dev, "request irq failed: %d\n", retval);
 		return retval;
 	}

 	retval = devm_gpiochip_add_data(&pdev->dev, &cg->chip, cg);
 	if (retval)
 		return retval;

 	/* Distuingish IRQ domain from others sharing (MFD) the same fwnode */
 	irq_domain_update_bus_token(cg->chip.irq.domain, DOMAIN_BUS_WIRED);

 	return 0;
 }

 static struct platform_driver crystalcove_gpio_driver = {
 	.probe = crystalcove_gpio_probe,
 	.driver = {
 		.name = "crystal_cove_gpio",
 	},
 };
 module_platform_driver(crystalcove_gpio_driver);

 MODULE_AUTHOR("Yang, Bin <bin.yang@intel.com>");
 MODULE_DESCRIPTION("Intel Crystal Cove GPIO Driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Intel Crystal Cove GPIO Driver
	*
	* Copyright (C) 2012, 2014 Intel Corporation. All rights reserved.
	*
	* Author: Yang, Bin <bin.yang@intel.com>
	*/

	#include <linux/bitops.h>
	#include <linux/gpio/driver.h>
	#include <linux/interrupt.h>
	#include <linux/mfd/intel_soc_pmic.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>
	#include <linux/seq_file.h>
	#include <linux/types.h>

	#define CRYSTALCOVE_GPIO_NUM 16
	#define CRYSTALCOVE_VGPIO_NUM 95

	#define UPDATE_IRQ_TYPE BIT(0)
	#define UPDATE_IRQ_MASK BIT(1)

	#define GPIO0IRQ 0x0b
	#define GPIO1IRQ 0x0c
	#define MGPIO0IRQS0 0x19
	#define MGPIO1IRQS0 0x1a
	#define MGPIO0IRQSX 0x1b
	#define MGPIO1IRQSX 0x1c
	#define GPIO0P0CTLO 0x2b
	#define GPIO0P0CTLI 0x33
	#define GPIO1P0CTLO 0x3b
	#define GPIO1P0CTLI 0x43
	#define GPIOPANELCTL 0x52

	#define CTLI_INTCNT_DIS (0)
	#define CTLI_INTCNT_NE (1 << 1)
	#define CTLI_INTCNT_PE (2 << 1)
	#define CTLI_INTCNT_BE (3 << 1)

	#define CTLO_DIR_IN (0)
	#define CTLO_DIR_OUT (1 << 5)

	#define CTLO_DRV_CMOS (0)
	#define CTLO_DRV_OD (1 << 4)

	#define CTLO_DRV_REN (1 << 3)

	#define CTLO_RVAL_2KDW (0)
	#define CTLO_RVAL_2KUP (1 << 1)
	#define CTLO_RVAL_50KDW (2 << 1)
	#define CTLO_RVAL_50KUP (3 << 1)

	#define CTLO_INPUT_SET (CTLO_DRV_CMOS \| CTLO_DRV_REN \| CTLO_RVAL_2KUP)
	#define CTLO_OUTPUT_SET (CTLO_DIR_OUT \| CTLO_INPUT_SET)

	enum ctrl_register {
	CTRL_IN,
	CTRL_OUT,
	};

	/**
	* struct crystalcove_gpio - Crystal Cove GPIO controller
	* @buslock: for bus lock/sync and unlock.
	* @chip: the abstract gpio_chip structure.
	* @regmap: the regmap from the parent device.
	* @update: pending IRQ setting update, to be written to the chip upon unlock.
	* @intcnt_value: the Interrupt Detect value to be written.
	* @set_irq_mask: true if the IRQ mask needs to be set, false to clear.
	*/
	struct crystalcove_gpio {
	struct mutex buslock; /* irq_bus_lock */
	struct gpio_chip chip;
	struct regmap *regmap;
	int update;
	int intcnt_value;
	bool set_irq_mask;
	};

	static inline int to_reg(int gpio, enum ctrl_register reg_type)
	{
	int reg;

	if (gpio >= CRYSTALCOVE_GPIO_NUM) {
	/*
	* Virtual GPIO called from ACPI, for now we only support
	* the panel ctl.
	*/
	switch (gpio) {
	case 0x5e:
	return GPIOPANELCTL;
	default:
	return -ENOTSUPP;
	}
	}

	if (reg_type == CTRL_IN) {
	if (gpio < 8)
	reg = GPIO0P0CTLI;
	else
	reg = GPIO1P0CTLI;
	} else {
	if (gpio < 8)
	reg = GPIO0P0CTLO;
	else
	reg = GPIO1P0CTLO;
	}

	return reg + gpio % 8;
	}

	static void crystalcove_update_irq_mask(struct crystalcove_gpio *cg, int gpio)
	{
	u8 mirqs0 = gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0;
	int mask = BIT(gpio % 8);

	if (cg->set_irq_mask)
	regmap_update_bits(cg->regmap, mirqs0, mask, mask);
	else
	regmap_update_bits(cg->regmap, mirqs0, mask, 0);
	}

	static void crystalcove_update_irq_ctrl(struct crystalcove_gpio *cg, int gpio)
	{
	int reg = to_reg(gpio, CTRL_IN);

	regmap_update_bits(cg->regmap, reg, CTLI_INTCNT_BE, cg->intcnt_value);
	}

	static int crystalcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
	int reg = to_reg(gpio, CTRL_OUT);

	if (reg < 0)
	return 0;

	return regmap_write(cg->regmap, reg, CTLO_INPUT_SET);
	}

	static int crystalcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio, int value)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
	int reg = to_reg(gpio, CTRL_OUT);

	if (reg < 0)
	return 0;

	return regmap_write(cg->regmap, reg, CTLO_OUTPUT_SET \| value);
	}

	static int crystalcove_gpio_get(struct gpio_chip *chip, unsigned int gpio)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
	unsigned int val;
	int ret, reg = to_reg(gpio, CTRL_IN);

	if (reg < 0)
	return 0;

	ret = regmap_read(cg->regmap, reg, &val);
	if (ret)
	return ret;

	return val & 0x1;
	}

	static void crystalcove_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
	int reg = to_reg(gpio, CTRL_OUT);

	if (reg < 0)
	return;

	if (value)
	regmap_update_bits(cg->regmap, reg, 1, 1);
	else
	regmap_update_bits(cg->regmap, reg, 1, 0);
	}

	static int crystalcove_irq_type(struct irq_data *data, unsigned int type)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));
	irq_hw_number_t hwirq = irqd_to_hwirq(data);

	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
	return 0;

	switch (type) {
	case IRQ_TYPE_NONE:
	cg->intcnt_value = CTLI_INTCNT_DIS;
	break;
	case IRQ_TYPE_EDGE_BOTH:
	cg->intcnt_value = CTLI_INTCNT_BE;
	break;
	case IRQ_TYPE_EDGE_RISING:
	cg->intcnt_value = CTLI_INTCNT_PE;
	break;
	case IRQ_TYPE_EDGE_FALLING:
	cg->intcnt_value = CTLI_INTCNT_NE;
	break;
	default:
	return -EINVAL;
	}

	cg->update \|= UPDATE_IRQ_TYPE;

	return 0;
	}

	static void crystalcove_bus_lock(struct irq_data *data)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));

	mutex_lock(&cg->buslock);
	}

	static void crystalcove_bus_sync_unlock(struct irq_data *data)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(irq_data_get_irq_chip_data(data));
	irq_hw_number_t hwirq = irqd_to_hwirq(data);

	if (cg->update & UPDATE_IRQ_TYPE)
	crystalcove_update_irq_ctrl(cg, hwirq);
	if (cg->update & UPDATE_IRQ_MASK)
	crystalcove_update_irq_mask(cg, hwirq);
	cg->update = 0;

	mutex_unlock(&cg->buslock);
	}

	static void crystalcove_irq_unmask(struct irq_data *data)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
	struct crystalcove_gpio *cg = gpiochip_get_data(gc);
	irq_hw_number_t hwirq = irqd_to_hwirq(data);

	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
	return;

	gpiochip_enable_irq(gc, hwirq);

	cg->set_irq_mask = false;
	cg->update \|= UPDATE_IRQ_MASK;
	}

	static void crystalcove_irq_mask(struct irq_data *data)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
	struct crystalcove_gpio *cg = gpiochip_get_data(gc);
	irq_hw_number_t hwirq = irqd_to_hwirq(data);

	if (hwirq >= CRYSTALCOVE_GPIO_NUM)
	return;

	cg->set_irq_mask = true;
	cg->update \|= UPDATE_IRQ_MASK;

	gpiochip_disable_irq(gc, hwirq);
	}

	static const struct irq_chip crystalcove_irqchip = {
	.name = "Crystal Cove",
	.irq_mask = crystalcove_irq_mask,
	.irq_unmask = crystalcove_irq_unmask,
	.irq_set_type = crystalcove_irq_type,
	.irq_bus_lock = crystalcove_bus_lock,
	.irq_bus_sync_unlock = crystalcove_bus_sync_unlock,
	.flags = IRQCHIP_SKIP_SET_WAKE \| IRQCHIP_IMMUTABLE,
	GPIOCHIP_IRQ_RESOURCE_HELPERS,
	};

	static irqreturn_t crystalcove_gpio_irq_handler(int irq, void *data)
	{
	struct crystalcove_gpio *cg = data;
	unsigned long pending;
	unsigned int p0, p1;
	int gpio;
	unsigned int virq;

	if (regmap_read(cg->regmap, GPIO0IRQ, &p0) \|\|
	regmap_read(cg->regmap, GPIO1IRQ, &p1))
	return IRQ_NONE;

	regmap_write(cg->regmap, GPIO0IRQ, p0);
	regmap_write(cg->regmap, GPIO1IRQ, p1);

	pending = p0 \| p1 << 8;

	for_each_set_bit(gpio, &pending, CRYSTALCOVE_GPIO_NUM) {
	virq = irq_find_mapping(cg->chip.irq.domain, gpio);
	handle_nested_irq(virq);
	}

	return IRQ_HANDLED;
	}

	static void crystalcove_gpio_dbg_show(struct seq_file s, struct gpio_chip chip)
	{
	struct crystalcove_gpio *cg = gpiochip_get_data(chip);
	int gpio, offset;
	unsigned int ctlo, ctli, mirqs0, mirqsx, irq;

	for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {
	regmap_read(cg->regmap, to_reg(gpio, CTRL_OUT), &ctlo);
	regmap_read(cg->regmap, to_reg(gpio, CTRL_IN), &ctli);
	regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0,
	&mirqs0);
	regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQSX : MGPIO1IRQSX,
	&mirqsx);
	regmap_read(cg->regmap, gpio < 8 ? GPIO0IRQ : GPIO1IRQ,
	&irq);

	offset = gpio % 8;
	seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s %s\n",
	gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ",
	ctli & 0x1 ? "hi" : "lo",
	ctli & CTLI_INTCNT_NE ? "fall" : " ",
	ctli & CTLI_INTCNT_PE ? "rise" : " ",
	ctlo,
	mirqs0 & BIT(offset) ? "s0 mask " : "s0 unmask",
	mirqsx & BIT(offset) ? "sx mask " : "sx unmask",
	irq & BIT(offset) ? "pending" : " ");
	}
	}

	static int crystalcove_gpio_probe(struct platform_device *pdev)
	{
	int irq = platform_get_irq(pdev, 0);
	struct crystalcove_gpio *cg;
	int retval;
	struct device *dev = pdev->dev.parent;
	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
	struct gpio_irq_chip *girq;

	if (irq < 0)
	return irq;

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

	mutex_init(&cg->buslock);
	cg->chip.label = KBUILD_MODNAME;
	cg->chip.direction_input = crystalcove_gpio_dir_in;
	cg->chip.direction_output = crystalcove_gpio_dir_out;
	cg->chip.get = crystalcove_gpio_get;
	cg->chip.set = crystalcove_gpio_set;
	cg->chip.base = -1;
	cg->chip.ngpio = CRYSTALCOVE_VGPIO_NUM;
	cg->chip.can_sleep = true;
	cg->chip.parent = dev;
	cg->chip.dbg_show = crystalcove_gpio_dbg_show;
	cg->regmap = pmic->regmap;

	girq = &cg->chip.irq;
	gpio_irq_chip_set_chip(girq, &crystalcove_irqchip);
	/* This will let us handle the parent IRQ in the driver */
	girq->parent_handler = NULL;
	girq->num_parents = 0;
	girq->parents = NULL;
	girq->default_type = IRQ_TYPE_NONE;
	girq->handler = handle_simple_irq;
	girq->threaded = true;

	retval = devm_request_threaded_irq(&pdev->dev, irq, NULL,
	crystalcove_gpio_irq_handler,
	IRQF_ONESHOT, KBUILD_MODNAME, cg);
	if (retval) {
	dev_warn(&pdev->dev, "request irq failed: %d\n", retval);
	return retval;
	}

	retval = devm_gpiochip_add_data(&pdev->dev, &cg->chip, cg);
	if (retval)
	return retval;

	/* Distuingish IRQ domain from others sharing (MFD) the same fwnode */
	irq_domain_update_bus_token(cg->chip.irq.domain, DOMAIN_BUS_WIRED);

	return 0;
	}

	static struct platform_driver crystalcove_gpio_driver = {
	.probe = crystalcove_gpio_probe,
	.driver = {
	.name = "crystal_cove_gpio",
	},
	};
	module_platform_driver(crystalcove_gpio_driver);

	MODULE_AUTHOR("Yang, Bin <bin.yang@intel.com>");
	MODULE_DESCRIPTION("Intel Crystal Cove GPIO Driver");
	MODULE_LICENSE("GPL v2");