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

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Intel Merrifield SoC GPIO driver
  *
  * Copyright (c) 2016 Intel Corporation.
  * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
  */

 #include <linux/acpi.h>
 #include <linux/bitops.h>
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/pinctrl/consumer.h>

 #define GCCR		0x000	/* controller configuration */
 #define GPLR		0x004	/* pin level r/o */
 #define GPDR		0x01c	/* pin direction */
 #define GPSR		0x034	/* pin set w/o */
 #define GPCR		0x04c	/* pin clear w/o */
 #define GRER		0x064	/* rising edge detect */
 #define GFER		0x07c	/* falling edge detect */
 #define GFBR		0x094	/* glitch filter bypass */
 #define GIMR		0x0ac	/* interrupt mask */
 #define GISR		0x0c4	/* interrupt source */
 #define GITR		0x300	/* input type */
 #define GLPR		0x318	/* level input polarity */
 #define GWMR		0x400	/* wake mask */
 #define GWSR		0x418	/* wake source */
 #define GSIR		0xc00	/* secure input */

 /* Intel Merrifield has 192 GPIO pins */
 #define MRFLD_NGPIO	192

 struct mrfld_gpio_pinrange {
 	unsigned int gpio_base;
 	unsigned int pin_base;
 	unsigned int npins;
 };

 #define GPIO_PINRANGE(gstart, gend, pstart)		\
 	{						\
 		.gpio_base = (gstart),			\
 		.pin_base = (pstart),			\
 		.npins = (gend) - (gstart) + 1,		\
 	}

 struct mrfld_gpio {
 	struct gpio_chip	chip;
 	void __iomem		*reg_base;
 	raw_spinlock_t		lock;
 	struct device		*dev;
 };

 static const struct mrfld_gpio_pinrange mrfld_gpio_ranges[] = {
 	GPIO_PINRANGE(0, 11, 146),
 	GPIO_PINRANGE(12, 13, 144),
 	GPIO_PINRANGE(14, 15, 35),
 	GPIO_PINRANGE(16, 16, 164),
 	GPIO_PINRANGE(17, 18, 105),
 	GPIO_PINRANGE(19, 22, 101),
 	GPIO_PINRANGE(23, 30, 107),
 	GPIO_PINRANGE(32, 43, 67),
 	GPIO_PINRANGE(44, 63, 195),
 	GPIO_PINRANGE(64, 67, 140),
 	GPIO_PINRANGE(68, 69, 165),
 	GPIO_PINRANGE(70, 71, 65),
 	GPIO_PINRANGE(72, 76, 228),
 	GPIO_PINRANGE(77, 86, 37),
 	GPIO_PINRANGE(87, 87, 48),
 	GPIO_PINRANGE(88, 88, 47),
 	GPIO_PINRANGE(89, 96, 49),
 	GPIO_PINRANGE(97, 97, 34),
 	GPIO_PINRANGE(102, 119, 83),
 	GPIO_PINRANGE(120, 123, 79),
 	GPIO_PINRANGE(124, 135, 115),
 	GPIO_PINRANGE(137, 142, 158),
 	GPIO_PINRANGE(154, 163, 24),
 	GPIO_PINRANGE(164, 176, 215),
 	GPIO_PINRANGE(177, 189, 127),
 	GPIO_PINRANGE(190, 191, 178),
 };

 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned int offset,
 			      unsigned int reg_type_offset)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	u8 reg = offset / 32;

 	return priv->reg_base + reg_type_offset + reg * 4;
 }

 static int mrfld_gpio_get(struct gpio_chip *chip, unsigned int offset)
 {
 	void __iomem *gplr = gpio_reg(chip, offset, GPLR);

 	return !!(readl(gplr) & BIT(offset % 32));
 }

 static void mrfld_gpio_set(struct gpio_chip *chip, unsigned int offset,
 			   int value)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	void __iomem *gpsr, *gpcr;
 	unsigned long flags;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	if (value) {
 		gpsr = gpio_reg(chip, offset, GPSR);
 		writel(BIT(offset % 32), gpsr);
 	} else {
 		gpcr = gpio_reg(chip, offset, GPCR);
 		writel(BIT(offset % 32), gpcr);
 	}

 	raw_spin_unlock_irqrestore(&priv->lock, flags);
 }

 static int mrfld_gpio_direction_input(struct gpio_chip *chip,
 				      unsigned int offset)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 	unsigned long flags;
 	u32 value;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	value = readl(gpdr);
 	value &= ~BIT(offset % 32);
 	writel(value, gpdr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);

 	return 0;
 }

 static int mrfld_gpio_direction_output(struct gpio_chip *chip,
 				       unsigned int offset, int value)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 	unsigned long flags;

 	mrfld_gpio_set(chip, offset, value);

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	value = readl(gpdr);
 	value |= BIT(offset % 32);
 	writel(value, gpdr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);

 	return 0;
 }

 static int mrfld_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
 {
 	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);

 	if (readl(gpdr) & BIT(offset % 32))
 		return GPIO_LINE_DIRECTION_OUT;

 	return GPIO_LINE_DIRECTION_IN;
 }

 static int mrfld_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset,
 				   unsigned int debounce)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	void __iomem *gfbr = gpio_reg(chip, offset, GFBR);
 	unsigned long flags;
 	u32 value;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	if (debounce)
 		value = readl(gfbr) & ~BIT(offset % 32);
 	else
 		value = readl(gfbr) | BIT(offset % 32);
 	writel(value, gfbr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);

 	return 0;
 }

 static int mrfld_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
 				 unsigned long config)
 {
 	u32 debounce;

 	if ((pinconf_to_config_param(config) == PIN_CONFIG_BIAS_DISABLE) ||
 	    (pinconf_to_config_param(config) == PIN_CONFIG_BIAS_PULL_UP) ||
 	    (pinconf_to_config_param(config) == PIN_CONFIG_BIAS_PULL_DOWN))
 		return gpiochip_generic_config(chip, offset, config);

 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
 		return -ENOTSUPP;

 	debounce = pinconf_to_config_argument(config);
 	return mrfld_gpio_set_debounce(chip, offset, debounce);
 }

 static void mrfld_irq_ack(struct irq_data *d)
 {
 	struct mrfld_gpio *priv = irq_data_get_irq_chip_data(d);
 	u32 gpio = irqd_to_hwirq(d);
 	void __iomem *gisr = gpio_reg(&priv->chip, gpio, GISR);
 	unsigned long flags;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	writel(BIT(gpio % 32), gisr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);
 }

 static void mrfld_irq_unmask_mask(struct irq_data *d, bool unmask)
 {
 	struct mrfld_gpio *priv = irq_data_get_irq_chip_data(d);
 	u32 gpio = irqd_to_hwirq(d);
 	void __iomem *gimr = gpio_reg(&priv->chip, gpio, GIMR);
 	unsigned long flags;
 	u32 value;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	if (unmask)
 		value = readl(gimr) | BIT(gpio % 32);
 	else
 		value = readl(gimr) & ~BIT(gpio % 32);
 	writel(value, gimr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);
 }

 static void mrfld_irq_mask(struct irq_data *d)
 {
 	mrfld_irq_unmask_mask(d, false);
 }

 static void mrfld_irq_unmask(struct irq_data *d)
 {
 	mrfld_irq_unmask_mask(d, true);
 }

 static int mrfld_irq_set_type(struct irq_data *d, unsigned int type)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct mrfld_gpio *priv = gpiochip_get_data(gc);
 	u32 gpio = irqd_to_hwirq(d);
 	void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
 	void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
 	void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR);
 	void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR);
 	unsigned long flags;
 	u32 value;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	if (type & IRQ_TYPE_EDGE_RISING)
 		value = readl(grer) | BIT(gpio % 32);
 	else
 		value = readl(grer) & ~BIT(gpio % 32);
 	writel(value, grer);

 	if (type & IRQ_TYPE_EDGE_FALLING)
 		value = readl(gfer) | BIT(gpio % 32);
 	else
 		value = readl(gfer) & ~BIT(gpio % 32);
 	writel(value, gfer);

 	/*
 	 * To prevent glitches from triggering an unintended level interrupt,
 	 * configure GLPR register first and then configure GITR.
 	 */
 	if (type & IRQ_TYPE_LEVEL_LOW)
 		value = readl(glpr) | BIT(gpio % 32);
 	else
 		value = readl(glpr) & ~BIT(gpio % 32);
 	writel(value, glpr);

 	if (type & IRQ_TYPE_LEVEL_MASK) {
 		value = readl(gitr) | BIT(gpio % 32);
 		writel(value, gitr);

 		irq_set_handler_locked(d, handle_level_irq);
 	} else if (type & IRQ_TYPE_EDGE_BOTH) {
 		value = readl(gitr) & ~BIT(gpio % 32);
 		writel(value, gitr);

 		irq_set_handler_locked(d, handle_edge_irq);
 	}

 	raw_spin_unlock_irqrestore(&priv->lock, flags);

 	return 0;
 }

 static int mrfld_irq_set_wake(struct irq_data *d, unsigned int on)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct mrfld_gpio *priv = gpiochip_get_data(gc);
 	u32 gpio = irqd_to_hwirq(d);
 	void __iomem *gwmr = gpio_reg(&priv->chip, gpio, GWMR);
 	void __iomem *gwsr = gpio_reg(&priv->chip, gpio, GWSR);
 	unsigned long flags;
 	u32 value;

 	raw_spin_lock_irqsave(&priv->lock, flags);

 	/* Clear the existing wake status */
 	writel(BIT(gpio % 32), gwsr);

 	if (on)
 		value = readl(gwmr) | BIT(gpio % 32);
 	else
 		value = readl(gwmr) & ~BIT(gpio % 32);
 	writel(value, gwmr);

 	raw_spin_unlock_irqrestore(&priv->lock, flags);

 	dev_dbg(priv->dev, "%sable wake for gpio %u\n", on ? "en" : "dis", gpio);
 	return 0;
 }

 static struct irq_chip mrfld_irqchip = {
 	.name		= "gpio-merrifield",
 	.irq_ack	= mrfld_irq_ack,
 	.irq_mask	= mrfld_irq_mask,
 	.irq_unmask	= mrfld_irq_unmask,
 	.irq_set_type	= mrfld_irq_set_type,
 	.irq_set_wake	= mrfld_irq_set_wake,
 };

 static void mrfld_irq_handler(struct irq_desc *desc)
 {
 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 	struct mrfld_gpio *priv = gpiochip_get_data(gc);
 	struct irq_chip *irqchip = irq_desc_get_chip(desc);
 	unsigned long base, gpio;

 	chained_irq_enter(irqchip, desc);

 	/* Check GPIO controller to check which pin triggered the interrupt */
 	for (base = 0; base < priv->chip.ngpio; base += 32) {
 		void __iomem *gisr = gpio_reg(&priv->chip, base, GISR);
 		void __iomem *gimr = gpio_reg(&priv->chip, base, GIMR);
 		unsigned long pending, enabled;

 		pending = readl(gisr);
 		enabled = readl(gimr);

 		/* Only interrupts that are enabled */
 		pending &= enabled;

 		for_each_set_bit(gpio, &pending, 32)
 			generic_handle_domain_irq(gc->irq.domain, base + gpio);
 	}

 	chained_irq_exit(irqchip, desc);
 }

 static int mrfld_irq_init_hw(struct gpio_chip *chip)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	void __iomem *reg;
 	unsigned int base;

 	for (base = 0; base < priv->chip.ngpio; base += 32) {
 		/* Clear the rising-edge detect register */
 		reg = gpio_reg(&priv->chip, base, GRER);
 		writel(0, reg);
 		/* Clear the falling-edge detect register */
 		reg = gpio_reg(&priv->chip, base, GFER);
 		writel(0, reg);
 	}

 	return 0;
 }

 static const char *mrfld_gpio_get_pinctrl_dev_name(struct mrfld_gpio *priv)
 {
 	struct acpi_device *adev;
 	const char *name;

 	adev = acpi_dev_get_first_match_dev("INTC1002", NULL, -1);
 	if (adev) {
 		name = devm_kstrdup(priv->dev, acpi_dev_name(adev), GFP_KERNEL);
 		acpi_dev_put(adev);
 	} else {
 		name = "pinctrl-merrifield";
 	}

 	return name;
 }

 static int mrfld_gpio_add_pin_ranges(struct gpio_chip *chip)
 {
 	struct mrfld_gpio *priv = gpiochip_get_data(chip);
 	const struct mrfld_gpio_pinrange *range;
 	const char *pinctrl_dev_name;
 	unsigned int i;
 	int retval;

 	pinctrl_dev_name = mrfld_gpio_get_pinctrl_dev_name(priv);
 	if (!pinctrl_dev_name)
 		return -ENOMEM;

 	for (i = 0; i < ARRAY_SIZE(mrfld_gpio_ranges); i++) {
 		range = &mrfld_gpio_ranges[i];
 		retval = gpiochip_add_pin_range(&priv->chip, pinctrl_dev_name,
 						range->gpio_base,
 						range->pin_base,
 						range->npins);
 		if (retval) {
 			dev_err(priv->dev, "failed to add GPIO pin range\n");
 			return retval;
 		}
 	}

 	return 0;
 }

 static int mrfld_gpio_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct gpio_irq_chip *girq;
 	struct mrfld_gpio *priv;
 	u32 gpio_base, irq_base;
 	void __iomem *base;
 	int retval;

 	retval = pcim_enable_device(pdev);
 	if (retval)
 		return retval;

 	retval = pcim_iomap_regions(pdev, BIT(1) | BIT(0), pci_name(pdev));
 	if (retval) {
 		dev_err(&pdev->dev, "I/O memory mapping error\n");
 		return retval;
 	}

 	base = pcim_iomap_table(pdev)[1];

 	irq_base = readl(base + 0 * sizeof(u32));
 	gpio_base = readl(base + 1 * sizeof(u32));

 	/* Release the IO mapping, since we already get the info from BAR1 */
 	pcim_iounmap_regions(pdev, BIT(1));

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

 	priv->dev = &pdev->dev;
 	priv->reg_base = pcim_iomap_table(pdev)[0];

 	priv->chip.label = dev_name(&pdev->dev);
 	priv->chip.parent = &pdev->dev;
 	priv->chip.request = gpiochip_generic_request;
 	priv->chip.free = gpiochip_generic_free;
 	priv->chip.direction_input = mrfld_gpio_direction_input;
 	priv->chip.direction_output = mrfld_gpio_direction_output;
 	priv->chip.get = mrfld_gpio_get;
 	priv->chip.set = mrfld_gpio_set;
 	priv->chip.get_direction = mrfld_gpio_get_direction;
 	priv->chip.set_config = mrfld_gpio_set_config;
 	priv->chip.base = gpio_base;
 	priv->chip.ngpio = MRFLD_NGPIO;
 	priv->chip.can_sleep = false;
 	priv->chip.add_pin_ranges = mrfld_gpio_add_pin_ranges;

 	raw_spin_lock_init(&priv->lock);

 	retval = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
 	if (retval < 0)
 		return retval;

 	girq = &priv->chip.irq;
 	girq->chip = &mrfld_irqchip;
 	girq->init_hw = mrfld_irq_init_hw;
 	girq->parent_handler = mrfld_irq_handler;
 	girq->num_parents = 1;
 	girq->parents = devm_kcalloc(&pdev->dev, girq->num_parents,
 				     sizeof(*girq->parents), GFP_KERNEL);
 	if (!girq->parents)
 		return -ENOMEM;
 	girq->parents[0] = pci_irq_vector(pdev, 0);
 	girq->first = irq_base;
 	girq->default_type = IRQ_TYPE_NONE;
 	girq->handler = handle_bad_irq;

 	retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
 	if (retval) {
 		dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
 		return retval;
 	}

 	pci_set_drvdata(pdev, priv);
 	return 0;
 }

 static const struct pci_device_id mrfld_gpio_ids[] = {
 	{ PCI_VDEVICE(INTEL, 0x1199) },
 	{ }
 };
 MODULE_DEVICE_TABLE(pci, mrfld_gpio_ids);

 static struct pci_driver mrfld_gpio_driver = {
 	.name		= "gpio-merrifield",
 	.id_table	= mrfld_gpio_ids,
 	.probe		= mrfld_gpio_probe,
 };

 module_pci_driver(mrfld_gpio_driver);

 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
 MODULE_DESCRIPTION("Intel Merrifield SoC GPIO driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Intel Merrifield SoC GPIO driver
	*
	* Copyright (c) 2016 Intel Corporation.
	* Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
	*/

	#include <linux/acpi.h>
	#include <linux/bitops.h>
	#include <linux/gpio/driver.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>
	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/pinctrl/consumer.h>

	#define GCCR 0x000 /* controller configuration */
	#define GPLR 0x004 /* pin level r/o */
	#define GPDR 0x01c /* pin direction */
	#define GPSR 0x034 /* pin set w/o */
	#define GPCR 0x04c /* pin clear w/o */
	#define GRER 0x064 /* rising edge detect */
	#define GFER 0x07c /* falling edge detect */
	#define GFBR 0x094 /* glitch filter bypass */
	#define GIMR 0x0ac /* interrupt mask */
	#define GISR 0x0c4 /* interrupt source */
	#define GITR 0x300 /* input type */
	#define GLPR 0x318 /* level input polarity */
	#define GWMR 0x400 /* wake mask */
	#define GWSR 0x418 /* wake source */
	#define GSIR 0xc00 /* secure input */

	/* Intel Merrifield has 192 GPIO pins */
	#define MRFLD_NGPIO 192

	struct mrfld_gpio_pinrange {
	unsigned int gpio_base;
	unsigned int pin_base;
	unsigned int npins;
	};

	#define GPIO_PINRANGE(gstart, gend, pstart) \
	{ \
	.gpio_base = (gstart), \
	.pin_base = (pstart), \
	.npins = (gend) - (gstart) + 1, \
	}

	struct mrfld_gpio {
	struct gpio_chip chip;
	void __iomem *reg_base;
	raw_spinlock_t lock;
	struct device *dev;
	};

	static const struct mrfld_gpio_pinrange mrfld_gpio_ranges[] = {
	GPIO_PINRANGE(0, 11, 146),
	GPIO_PINRANGE(12, 13, 144),
	GPIO_PINRANGE(14, 15, 35),
	GPIO_PINRANGE(16, 16, 164),
	GPIO_PINRANGE(17, 18, 105),
	GPIO_PINRANGE(19, 22, 101),
	GPIO_PINRANGE(23, 30, 107),
	GPIO_PINRANGE(32, 43, 67),
	GPIO_PINRANGE(44, 63, 195),
	GPIO_PINRANGE(64, 67, 140),
	GPIO_PINRANGE(68, 69, 165),
	GPIO_PINRANGE(70, 71, 65),
	GPIO_PINRANGE(72, 76, 228),
	GPIO_PINRANGE(77, 86, 37),
	GPIO_PINRANGE(87, 87, 48),
	GPIO_PINRANGE(88, 88, 47),
	GPIO_PINRANGE(89, 96, 49),
	GPIO_PINRANGE(97, 97, 34),
	GPIO_PINRANGE(102, 119, 83),
	GPIO_PINRANGE(120, 123, 79),
	GPIO_PINRANGE(124, 135, 115),
	GPIO_PINRANGE(137, 142, 158),
	GPIO_PINRANGE(154, 163, 24),
	GPIO_PINRANGE(164, 176, 215),
	GPIO_PINRANGE(177, 189, 127),
	GPIO_PINRANGE(190, 191, 178),
	};

	static void __iomem gpio_reg(struct gpio_chip chip, unsigned int offset,
	unsigned int reg_type_offset)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	u8 reg = offset / 32;

	return priv->reg_base + reg_type_offset + reg * 4;
	}

	static int mrfld_gpio_get(struct gpio_chip *chip, unsigned int offset)
	{
	void __iomem *gplr = gpio_reg(chip, offset, GPLR);

	return !!(readl(gplr) & BIT(offset % 32));
	}

	static void mrfld_gpio_set(struct gpio_chip *chip, unsigned int offset,
	int value)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	void __iomem gpsr, gpcr;
	unsigned long flags;

	raw_spin_lock_irqsave(&priv->lock, flags);

	if (value) {
	gpsr = gpio_reg(chip, offset, GPSR);
	writel(BIT(offset % 32), gpsr);
	} else {
	gpcr = gpio_reg(chip, offset, GPCR);
	writel(BIT(offset % 32), gpcr);
	}

	raw_spin_unlock_irqrestore(&priv->lock, flags);
	}

	static int mrfld_gpio_direction_input(struct gpio_chip *chip,
	unsigned int offset)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
	unsigned long flags;
	u32 value;

	raw_spin_lock_irqsave(&priv->lock, flags);

	value = readl(gpdr);
	value &= ~BIT(offset % 32);
	writel(value, gpdr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);

	return 0;
	}

	static int mrfld_gpio_direction_output(struct gpio_chip *chip,
	unsigned int offset, int value)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
	unsigned long flags;

	mrfld_gpio_set(chip, offset, value);

	raw_spin_lock_irqsave(&priv->lock, flags);

	value = readl(gpdr);
	value \|= BIT(offset % 32);
	writel(value, gpdr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);

	return 0;
	}

	static int mrfld_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
	{
	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);

	if (readl(gpdr) & BIT(offset % 32))
	return GPIO_LINE_DIRECTION_OUT;

	return GPIO_LINE_DIRECTION_IN;
	}

	static int mrfld_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset,
	unsigned int debounce)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	void __iomem *gfbr = gpio_reg(chip, offset, GFBR);
	unsigned long flags;
	u32 value;

	raw_spin_lock_irqsave(&priv->lock, flags);

	if (debounce)
	value = readl(gfbr) & ~BIT(offset % 32);
	else
	value = readl(gfbr) \| BIT(offset % 32);
	writel(value, gfbr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);

	return 0;
	}

	static int mrfld_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
	unsigned long config)
	{
	u32 debounce;

	if ((pinconf_to_config_param(config) == PIN_CONFIG_BIAS_DISABLE) \|\|
	(pinconf_to_config_param(config) == PIN_CONFIG_BIAS_PULL_UP) \|\|
	(pinconf_to_config_param(config) == PIN_CONFIG_BIAS_PULL_DOWN))
	return gpiochip_generic_config(chip, offset, config);

	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
	return -ENOTSUPP;

	debounce = pinconf_to_config_argument(config);
	return mrfld_gpio_set_debounce(chip, offset, debounce);
	}

	static void mrfld_irq_ack(struct irq_data *d)
	{
	struct mrfld_gpio *priv = irq_data_get_irq_chip_data(d);
	u32 gpio = irqd_to_hwirq(d);
	void __iomem *gisr = gpio_reg(&priv->chip, gpio, GISR);
	unsigned long flags;

	raw_spin_lock_irqsave(&priv->lock, flags);

	writel(BIT(gpio % 32), gisr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);
	}

	static void mrfld_irq_unmask_mask(struct irq_data *d, bool unmask)
	{
	struct mrfld_gpio *priv = irq_data_get_irq_chip_data(d);
	u32 gpio = irqd_to_hwirq(d);
	void __iomem *gimr = gpio_reg(&priv->chip, gpio, GIMR);
	unsigned long flags;
	u32 value;

	raw_spin_lock_irqsave(&priv->lock, flags);

	if (unmask)
	value = readl(gimr) \| BIT(gpio % 32);
	else
	value = readl(gimr) & ~BIT(gpio % 32);
	writel(value, gimr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);
	}

	static void mrfld_irq_mask(struct irq_data *d)
	{
	mrfld_irq_unmask_mask(d, false);
	}

	static void mrfld_irq_unmask(struct irq_data *d)
	{
	mrfld_irq_unmask_mask(d, true);
	}

	static int mrfld_irq_set_type(struct irq_data *d, unsigned int type)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct mrfld_gpio *priv = gpiochip_get_data(gc);
	u32 gpio = irqd_to_hwirq(d);
	void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
	void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
	void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR);
	void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR);
	unsigned long flags;
	u32 value;

	raw_spin_lock_irqsave(&priv->lock, flags);

	if (type & IRQ_TYPE_EDGE_RISING)
	value = readl(grer) \| BIT(gpio % 32);
	else
	value = readl(grer) & ~BIT(gpio % 32);
	writel(value, grer);

	if (type & IRQ_TYPE_EDGE_FALLING)
	value = readl(gfer) \| BIT(gpio % 32);
	else
	value = readl(gfer) & ~BIT(gpio % 32);
	writel(value, gfer);

	/*
	* To prevent glitches from triggering an unintended level interrupt,
	* configure GLPR register first and then configure GITR.
	*/
	if (type & IRQ_TYPE_LEVEL_LOW)
	value = readl(glpr) \| BIT(gpio % 32);
	else
	value = readl(glpr) & ~BIT(gpio % 32);
	writel(value, glpr);

	if (type & IRQ_TYPE_LEVEL_MASK) {
	value = readl(gitr) \| BIT(gpio % 32);
	writel(value, gitr);

	irq_set_handler_locked(d, handle_level_irq);
	} else if (type & IRQ_TYPE_EDGE_BOTH) {
	value = readl(gitr) & ~BIT(gpio % 32);
	writel(value, gitr);

	irq_set_handler_locked(d, handle_edge_irq);
	}

	raw_spin_unlock_irqrestore(&priv->lock, flags);

	return 0;
	}

	static int mrfld_irq_set_wake(struct irq_data *d, unsigned int on)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct mrfld_gpio *priv = gpiochip_get_data(gc);
	u32 gpio = irqd_to_hwirq(d);
	void __iomem *gwmr = gpio_reg(&priv->chip, gpio, GWMR);
	void __iomem *gwsr = gpio_reg(&priv->chip, gpio, GWSR);
	unsigned long flags;
	u32 value;

	raw_spin_lock_irqsave(&priv->lock, flags);

	/* Clear the existing wake status */
	writel(BIT(gpio % 32), gwsr);

	if (on)
	value = readl(gwmr) \| BIT(gpio % 32);
	else
	value = readl(gwmr) & ~BIT(gpio % 32);
	writel(value, gwmr);

	raw_spin_unlock_irqrestore(&priv->lock, flags);

	dev_dbg(priv->dev, "%sable wake for gpio %u\n", on ? "en" : "dis", gpio);
	return 0;
	}

	static struct irq_chip mrfld_irqchip = {
	.name = "gpio-merrifield",
	.irq_ack = mrfld_irq_ack,
	.irq_mask = mrfld_irq_mask,
	.irq_unmask = mrfld_irq_unmask,
	.irq_set_type = mrfld_irq_set_type,
	.irq_set_wake = mrfld_irq_set_wake,
	};

	static void mrfld_irq_handler(struct irq_desc *desc)
	{
	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
	struct mrfld_gpio *priv = gpiochip_get_data(gc);
	struct irq_chip *irqchip = irq_desc_get_chip(desc);
	unsigned long base, gpio;

	chained_irq_enter(irqchip, desc);

	/* Check GPIO controller to check which pin triggered the interrupt */
	for (base = 0; base < priv->chip.ngpio; base += 32) {
	void __iomem *gisr = gpio_reg(&priv->chip, base, GISR);
	void __iomem *gimr = gpio_reg(&priv->chip, base, GIMR);
	unsigned long pending, enabled;

	pending = readl(gisr);
	enabled = readl(gimr);

	/* Only interrupts that are enabled */
	pending &= enabled;

	for_each_set_bit(gpio, &pending, 32)
	generic_handle_domain_irq(gc->irq.domain, base + gpio);
	}

	chained_irq_exit(irqchip, desc);
	}

	static int mrfld_irq_init_hw(struct gpio_chip *chip)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	void __iomem *reg;
	unsigned int base;

	for (base = 0; base < priv->chip.ngpio; base += 32) {
	/* Clear the rising-edge detect register */
	reg = gpio_reg(&priv->chip, base, GRER);
	writel(0, reg);
	/* Clear the falling-edge detect register */
	reg = gpio_reg(&priv->chip, base, GFER);
	writel(0, reg);
	}

	return 0;
	}

	static const char mrfld_gpio_get_pinctrl_dev_name(struct mrfld_gpio priv)
	{
	struct acpi_device *adev;
	const char *name;

	adev = acpi_dev_get_first_match_dev("INTC1002", NULL, -1);
	if (adev) {
	name = devm_kstrdup(priv->dev, acpi_dev_name(adev), GFP_KERNEL);
	acpi_dev_put(adev);
	} else {
	name = "pinctrl-merrifield";
	}

	return name;
	}

	static int mrfld_gpio_add_pin_ranges(struct gpio_chip *chip)
	{
	struct mrfld_gpio *priv = gpiochip_get_data(chip);
	const struct mrfld_gpio_pinrange *range;
	const char *pinctrl_dev_name;
	unsigned int i;
	int retval;

	pinctrl_dev_name = mrfld_gpio_get_pinctrl_dev_name(priv);
	if (!pinctrl_dev_name)
	return -ENOMEM;

	for (i = 0; i < ARRAY_SIZE(mrfld_gpio_ranges); i++) {
	range = &mrfld_gpio_ranges[i];
	retval = gpiochip_add_pin_range(&priv->chip, pinctrl_dev_name,
	range->gpio_base,
	range->pin_base,
	range->npins);
	if (retval) {
	dev_err(priv->dev, "failed to add GPIO pin range\n");
	return retval;
	}
	}

	return 0;
	}

	static int mrfld_gpio_probe(struct pci_dev pdev, const struct pci_device_id id)
	{
	struct gpio_irq_chip *girq;
	struct mrfld_gpio *priv;
	u32 gpio_base, irq_base;
	void __iomem *base;
	int retval;

	retval = pcim_enable_device(pdev);
	if (retval)
	return retval;

	retval = pcim_iomap_regions(pdev, BIT(1) \| BIT(0), pci_name(pdev));
	if (retval) {
	dev_err(&pdev->dev, "I/O memory mapping error\n");
	return retval;
	}

	base = pcim_iomap_table(pdev)[1];

	irq_base = readl(base + 0 * sizeof(u32));
	gpio_base = readl(base + 1 * sizeof(u32));

	/* Release the IO mapping, since we already get the info from BAR1 */
	pcim_iounmap_regions(pdev, BIT(1));

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

	priv->dev = &pdev->dev;
	priv->reg_base = pcim_iomap_table(pdev)[0];

	priv->chip.label = dev_name(&pdev->dev);
	priv->chip.parent = &pdev->dev;
	priv->chip.request = gpiochip_generic_request;
	priv->chip.free = gpiochip_generic_free;
	priv->chip.direction_input = mrfld_gpio_direction_input;
	priv->chip.direction_output = mrfld_gpio_direction_output;
	priv->chip.get = mrfld_gpio_get;
	priv->chip.set = mrfld_gpio_set;
	priv->chip.get_direction = mrfld_gpio_get_direction;
	priv->chip.set_config = mrfld_gpio_set_config;
	priv->chip.base = gpio_base;
	priv->chip.ngpio = MRFLD_NGPIO;
	priv->chip.can_sleep = false;
	priv->chip.add_pin_ranges = mrfld_gpio_add_pin_ranges;

	raw_spin_lock_init(&priv->lock);

	retval = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
	if (retval < 0)
	return retval;

	girq = &priv->chip.irq;
	girq->chip = &mrfld_irqchip;
	girq->init_hw = mrfld_irq_init_hw;
	girq->parent_handler = mrfld_irq_handler;
	girq->num_parents = 1;
	girq->parents = devm_kcalloc(&pdev->dev, girq->num_parents,
	sizeof(*girq->parents), GFP_KERNEL);
	if (!girq->parents)
	return -ENOMEM;
	girq->parents[0] = pci_irq_vector(pdev, 0);
	girq->first = irq_base;
	girq->default_type = IRQ_TYPE_NONE;
	girq->handler = handle_bad_irq;

	retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
	if (retval) {
	dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
	return retval;
	}

	pci_set_drvdata(pdev, priv);
	return 0;
	}

	static const struct pci_device_id mrfld_gpio_ids[] = {
	{ PCI_VDEVICE(INTEL, 0x1199) },
	{ }
	};
	MODULE_DEVICE_TABLE(pci, mrfld_gpio_ids);

	static struct pci_driver mrfld_gpio_driver = {
	.name = "gpio-merrifield",
	.id_table = mrfld_gpio_ids,
	.probe = mrfld_gpio_probe,
	};

	module_pci_driver(mrfld_gpio_driver);

	MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
	MODULE_DESCRIPTION("Intel Merrifield SoC GPIO driver");
	MODULE_LICENSE("GPL v2");