drivers/gpio/gpio-pxa.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  *  linux/arch/arm/plat-pxa/gpio.c
  *
  *  Generic PXA GPIO handling
  *
  *  Author:	Nicolas Pitre
  *  Created:	Jun 15, 2001
  *  Copyright:	MontaVista Software Inc.
  *
  *  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.
  */
 #include <linux/module.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/gpio.h>
 #include <linux/gpio-pxa.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/syscore_ops.h>
 #include <linux/slab.h>

 /*
  * We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
  * one set of registers. The register offsets are organized below:
  *
  *           GPLR    GPDR    GPSR    GPCR    GRER    GFER    GEDR
  * BANK 0 - 0x0000  0x000C  0x0018  0x0024  0x0030  0x003C  0x0048
  * BANK 1 - 0x0004  0x0010  0x001C  0x0028  0x0034  0x0040  0x004C
  * BANK 2 - 0x0008  0x0014  0x0020  0x002C  0x0038  0x0044  0x0050
  *
  * BANK 3 - 0x0100  0x010C  0x0118  0x0124  0x0130  0x013C  0x0148
  * BANK 4 - 0x0104  0x0110  0x011C  0x0128  0x0134  0x0140  0x014C
  * BANK 5 - 0x0108  0x0114  0x0120  0x012C  0x0138  0x0144  0x0150
  *
  * BANK 6 - 0x0200  0x020C  0x0218  0x0224  0x0230  0x023C  0x0248
  *
  * NOTE:
  *   BANK 3 is only available on PXA27x and later processors.
  *   BANK 4 and 5 are only available on PXA935, PXA1928
  *   BANK 6 is only available on PXA1928
  */

 #define GPLR_OFFSET	0x00
 #define GPDR_OFFSET	0x0C
 #define GPSR_OFFSET	0x18
 #define GPCR_OFFSET	0x24
 #define GRER_OFFSET	0x30
 #define GFER_OFFSET	0x3C
 #define GEDR_OFFSET	0x48
 #define GAFR_OFFSET	0x54
 #define ED_MASK_OFFSET	0x9C	/* GPIO edge detection for AP side */

 #define BANK_OFF(n)	(((n) / 3) << 8) + (((n) % 3) << 2)

 int pxa_last_gpio;
 static int irq_base;

 struct pxa_gpio_bank {
 	void __iomem	*regbase;
 	unsigned long	irq_mask;
 	unsigned long	irq_edge_rise;
 	unsigned long	irq_edge_fall;

 #ifdef CONFIG_PM
 	unsigned long	saved_gplr;
 	unsigned long	saved_gpdr;
 	unsigned long	saved_grer;
 	unsigned long	saved_gfer;
 #endif
 };

 struct pxa_gpio_chip {
 	struct device *dev;
 	struct gpio_chip chip;
 	struct pxa_gpio_bank *banks;
 	struct irq_domain *irqdomain;

 	int irq0;
 	int irq1;
 	int (*set_wake)(unsigned int gpio, unsigned int on);
 };

 enum pxa_gpio_type {
 	PXA25X_GPIO = 0,
 	PXA26X_GPIO,
 	PXA27X_GPIO,
 	PXA3XX_GPIO,
 	PXA93X_GPIO,
 	MMP_GPIO = 0x10,
 	MMP2_GPIO,
 	PXA1928_GPIO,
 };

 struct pxa_gpio_id {
 	enum pxa_gpio_type	type;
 	int			gpio_nums;
 };

 static DEFINE_SPINLOCK(gpio_lock);
 static struct pxa_gpio_chip *pxa_gpio_chip;
 static enum pxa_gpio_type gpio_type;

 static struct pxa_gpio_id pxa25x_id = {
 	.type		= PXA25X_GPIO,
 	.gpio_nums	= 85,
 };

 static struct pxa_gpio_id pxa26x_id = {
 	.type		= PXA26X_GPIO,
 	.gpio_nums	= 90,
 };

 static struct pxa_gpio_id pxa27x_id = {
 	.type		= PXA27X_GPIO,
 	.gpio_nums	= 121,
 };

 static struct pxa_gpio_id pxa3xx_id = {
 	.type		= PXA3XX_GPIO,
 	.gpio_nums	= 128,
 };

 static struct pxa_gpio_id pxa93x_id = {
 	.type		= PXA93X_GPIO,
 	.gpio_nums	= 192,
 };

 static struct pxa_gpio_id mmp_id = {
 	.type		= MMP_GPIO,
 	.gpio_nums	= 128,
 };

 static struct pxa_gpio_id mmp2_id = {
 	.type		= MMP2_GPIO,
 	.gpio_nums	= 192,
 };

 static struct pxa_gpio_id pxa1928_id = {
 	.type		= PXA1928_GPIO,
 	.gpio_nums	= 224,
 };

 #define for_each_gpio_bank(i, b, pc)					\
 	for (i = 0, b = pc->banks; i <= pxa_last_gpio; i += 32, b++)

 static inline struct pxa_gpio_chip *chip_to_pxachip(struct gpio_chip *c)
 {
 	struct pxa_gpio_chip *pxa_chip = gpiochip_get_data(c);

 	return pxa_chip;
 }

 static inline void __iomem *gpio_bank_base(struct gpio_chip *c, int gpio)
 {
 	struct pxa_gpio_chip *p = gpiochip_get_data(c);
 	struct pxa_gpio_bank *bank = p->banks + (gpio / 32);

 	return bank->regbase;
 }

 static inline struct pxa_gpio_bank *gpio_to_pxabank(struct gpio_chip *c,
 						    unsigned gpio)
 {
 	return chip_to_pxachip(c)->banks + gpio / 32;
 }

 static inline int gpio_is_pxa_type(int type)
 {
 	return (type & MMP_GPIO) == 0;
 }

 static inline int gpio_is_mmp_type(int type)
 {
 	return (type & MMP_GPIO) != 0;
 }

 /* GPIO86/87/88/89 on PXA26x have their direction bits in PXA_GPDR(2 inverted,
  * as well as their Alternate Function value being '1' for GPIO in GAFRx.
  */
 static inline int __gpio_is_inverted(int gpio)
 {
 	if ((gpio_type == PXA26X_GPIO) && (gpio > 85))
 		return 1;
 	return 0;
 }

 /*
  * On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
  * function of a GPIO, and GPDRx cannot be altered once configured. It
  * is attributed as "occupied" here (I know this terminology isn't
  * accurate, you are welcome to propose a better one :-)
  */
 static inline int __gpio_is_occupied(struct pxa_gpio_chip *pchip, unsigned gpio)
 {
 	void __iomem *base;
 	unsigned long gafr = 0, gpdr = 0;
 	int ret, af = 0, dir = 0;

 	base = gpio_bank_base(&pchip->chip, gpio);
 	gpdr = readl_relaxed(base + GPDR_OFFSET);

 	switch (gpio_type) {
 	case PXA25X_GPIO:
 	case PXA26X_GPIO:
 	case PXA27X_GPIO:
 		gafr = readl_relaxed(base + GAFR_OFFSET);
 		af = (gafr >> ((gpio & 0xf) * 2)) & 0x3;
 		dir = gpdr & GPIO_bit(gpio);

 		if (__gpio_is_inverted(gpio))
 			ret = (af != 1) || (dir == 0);
 		else
 			ret = (af != 0) || (dir != 0);
 		break;
 	default:
 		ret = gpdr & GPIO_bit(gpio);
 		break;
 	}
 	return ret;
 }

 int pxa_irq_to_gpio(int irq)
 {
 	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
 	int irq_gpio0;

 	irq_gpio0 = irq_find_mapping(pchip->irqdomain, 0);
 	if (irq_gpio0 > 0)
 		return irq - irq_gpio0;

 	return irq_gpio0;
 }

 static int pxa_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
 	struct pxa_gpio_chip *pchip = chip_to_pxachip(chip);

 	return irq_find_mapping(pchip->irqdomain, offset);
 }

 static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 {
 	void __iomem *base = gpio_bank_base(chip, offset);
 	uint32_t value, mask = GPIO_bit(offset);
 	unsigned long flags;
 	int ret;

 	ret = pinctrl_gpio_direction_input(chip->base + offset);
 	if (!ret)
 		return 0;

 	spin_lock_irqsave(&gpio_lock, flags);

 	value = readl_relaxed(base + GPDR_OFFSET);
 	if (__gpio_is_inverted(chip->base + offset))
 		value |= mask;
 	else
 		value &= ~mask;
 	writel_relaxed(value, base + GPDR_OFFSET);

 	spin_unlock_irqrestore(&gpio_lock, flags);
 	return 0;
 }

 static int pxa_gpio_direction_output(struct gpio_chip *chip,
 				     unsigned offset, int value)
 {
 	void __iomem *base = gpio_bank_base(chip, offset);
 	uint32_t tmp, mask = GPIO_bit(offset);
 	unsigned long flags;
 	int ret;

 	writel_relaxed(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));

 	ret = pinctrl_gpio_direction_output(chip->base + offset);
 	if (ret)
 		return ret;

 	spin_lock_irqsave(&gpio_lock, flags);

 	tmp = readl_relaxed(base + GPDR_OFFSET);
 	if (__gpio_is_inverted(chip->base + offset))
 		tmp &= ~mask;
 	else
 		tmp |= mask;
 	writel_relaxed(tmp, base + GPDR_OFFSET);

 	spin_unlock_irqrestore(&gpio_lock, flags);
 	return 0;
 }

 static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
 	void __iomem *base = gpio_bank_base(chip, offset);
 	u32 gplr = readl_relaxed(base + GPLR_OFFSET);

 	return !!(gplr & GPIO_bit(offset));
 }

 static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
 	void __iomem *base = gpio_bank_base(chip, offset);

 	writel_relaxed(GPIO_bit(offset),
 		       base + (value ? GPSR_OFFSET : GPCR_OFFSET));
 }

 #ifdef CONFIG_OF_GPIO
 static int pxa_gpio_of_xlate(struct gpio_chip *gc,
 			     const struct of_phandle_args *gpiospec,
 			     u32 *flags)
 {
 	if (gpiospec->args[0] > pxa_last_gpio)
 		return -EINVAL;

 	if (flags)
 		*flags = gpiospec->args[1];

 	return gpiospec->args[0];
 }
 #endif

 static int pxa_gpio_request(struct gpio_chip *chip, unsigned int offset)
 {
 	return pinctrl_request_gpio(chip->base + offset);
 }

 static void pxa_gpio_free(struct gpio_chip *chip, unsigned int offset)
 {
 	pinctrl_free_gpio(chip->base + offset);
 }

 static int pxa_init_gpio_chip(struct pxa_gpio_chip *pchip, int ngpio,
 			      struct device_node *np, void __iomem *regbase)
 {
 	int i, gpio, nbanks = DIV_ROUND_UP(ngpio, 32);
 	struct pxa_gpio_bank *bank;

 	pchip->banks = devm_kcalloc(pchip->dev, nbanks, sizeof(*pchip->banks),
 				    GFP_KERNEL);
 	if (!pchip->banks)
 		return -ENOMEM;

 	pchip->chip.label = "gpio-pxa";
 	pchip->chip.direction_input  = pxa_gpio_direction_input;
 	pchip->chip.direction_output = pxa_gpio_direction_output;
 	pchip->chip.get = pxa_gpio_get;
 	pchip->chip.set = pxa_gpio_set;
 	pchip->chip.to_irq = pxa_gpio_to_irq;
 	pchip->chip.ngpio = ngpio;
 	pchip->chip.request = pxa_gpio_request;
 	pchip->chip.free = pxa_gpio_free;
 #ifdef CONFIG_OF_GPIO
 	pchip->chip.of_node = np;
 	pchip->chip.of_xlate = pxa_gpio_of_xlate;
 	pchip->chip.of_gpio_n_cells = 2;
 #endif

 	for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
 		bank = pchip->banks + i;
 		bank->regbase = regbase + BANK_OFF(i);
 	}

 	return gpiochip_add_data(&pchip->chip, pchip);
 }

 /* Update only those GRERx and GFERx edge detection register bits if those
  * bits are set in c->irq_mask
  */
 static inline void update_edge_detect(struct pxa_gpio_bank *c)
 {
 	uint32_t grer, gfer;

 	grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~c->irq_mask;
 	gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~c->irq_mask;
 	grer |= c->irq_edge_rise & c->irq_mask;
 	gfer |= c->irq_edge_fall & c->irq_mask;
 	writel_relaxed(grer, c->regbase + GRER_OFFSET);
 	writel_relaxed(gfer, c->regbase + GFER_OFFSET);
 }

 static int pxa_gpio_irq_type(struct irq_data *d, unsigned int type)
 {
 	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
 	unsigned int gpio = irqd_to_hwirq(d);
 	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);
 	unsigned long gpdr, mask = GPIO_bit(gpio);

 	if (type == IRQ_TYPE_PROBE) {
 		/* Don't mess with enabled GPIOs using preconfigured edges or
 		 * GPIOs set to alternate function or to output during probe
 		 */
 		if ((c->irq_edge_rise | c->irq_edge_fall) & GPIO_bit(gpio))
 			return 0;

 		if (__gpio_is_occupied(pchip, gpio))
 			return 0;

 		type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
 	}

 	gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);

 	if (__gpio_is_inverted(gpio))
 		writel_relaxed(gpdr | mask,  c->regbase + GPDR_OFFSET);
 	else
 		writel_relaxed(gpdr & ~mask, c->regbase + GPDR_OFFSET);

 	if (type & IRQ_TYPE_EDGE_RISING)
 		c->irq_edge_rise |= mask;
 	else
 		c->irq_edge_rise &= ~mask;

 	if (type & IRQ_TYPE_EDGE_FALLING)
 		c->irq_edge_fall |= mask;
 	else
 		c->irq_edge_fall &= ~mask;

 	update_edge_detect(c);

 	pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, d->irq, gpio,
 		((type & IRQ_TYPE_EDGE_RISING)  ? " rising"  : ""),
 		((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
 	return 0;
 }

 static irqreturn_t pxa_gpio_demux_handler(int in_irq, void *d)
 {
 	int loop, gpio, n, handled = 0;
 	unsigned long gedr;
 	struct pxa_gpio_chip *pchip = d;
 	struct pxa_gpio_bank *c;

 	do {
 		loop = 0;
 		for_each_gpio_bank(gpio, c, pchip) {
 			gedr = readl_relaxed(c->regbase + GEDR_OFFSET);
 			gedr = gedr & c->irq_mask;
 			writel_relaxed(gedr, c->regbase + GEDR_OFFSET);

 			for_each_set_bit(n, &gedr, BITS_PER_LONG) {
 				loop = 1;

 				generic_handle_irq(
 					irq_find_mapping(pchip->irqdomain,
 							 gpio + n));
 			}
 		}
 		handled += loop;
 	} while (loop);

 	return handled ? IRQ_HANDLED : IRQ_NONE;
 }

 static irqreturn_t pxa_gpio_direct_handler(int in_irq, void *d)
 {
 	struct pxa_gpio_chip *pchip = d;

 	if (in_irq == pchip->irq0) {
 		generic_handle_irq(irq_find_mapping(pchip->irqdomain, 0));
 	} else if (in_irq == pchip->irq1) {
 		generic_handle_irq(irq_find_mapping(pchip->irqdomain, 1));
 	} else {
 		pr_err("%s() unknown irq %d\n", __func__, in_irq);
 		return IRQ_NONE;
 	}
 	return IRQ_HANDLED;
 }

 static void pxa_ack_muxed_gpio(struct irq_data *d)
 {
 	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
 	unsigned int gpio = irqd_to_hwirq(d);
 	void __iomem *base = gpio_bank_base(&pchip->chip, gpio);

 	writel_relaxed(GPIO_bit(gpio), base + GEDR_OFFSET);
 }

 static void pxa_mask_muxed_gpio(struct irq_data *d)
 {
 	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
 	unsigned int gpio = irqd_to_hwirq(d);
 	struct pxa_gpio_bank *b = gpio_to_pxabank(&pchip->chip, gpio);
 	void __iomem *base = gpio_bank_base(&pchip->chip, gpio);
 	uint32_t grer, gfer;

 	b->irq_mask &= ~GPIO_bit(gpio);

 	grer = readl_relaxed(base + GRER_OFFSET) & ~GPIO_bit(gpio);
 	gfer = readl_relaxed(base + GFER_OFFSET) & ~GPIO_bit(gpio);
 	writel_relaxed(grer, base + GRER_OFFSET);
 	writel_relaxed(gfer, base + GFER_OFFSET);
 }

 static int pxa_gpio_set_wake(struct irq_data *d, unsigned int on)
 {
 	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
 	unsigned int gpio = irqd_to_hwirq(d);

 	if (pchip->set_wake)
 		return pchip->set_wake(gpio, on);
 	else
 		return 0;
 }

 static void pxa_unmask_muxed_gpio(struct irq_data *d)
 {
 	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
 	unsigned int gpio = irqd_to_hwirq(d);
 	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);

 	c->irq_mask |= GPIO_bit(gpio);
 	update_edge_detect(c);
 }

 static struct irq_chip pxa_muxed_gpio_chip = {
 	.name		= "GPIO",
 	.irq_ack	= pxa_ack_muxed_gpio,
 	.irq_mask	= pxa_mask_muxed_gpio,
 	.irq_unmask	= pxa_unmask_muxed_gpio,
 	.irq_set_type	= pxa_gpio_irq_type,
 	.irq_set_wake	= pxa_gpio_set_wake,
 };

 static int pxa_gpio_nums(struct platform_device *pdev)
 {
 	const struct platform_device_id *id = platform_get_device_id(pdev);
 	struct pxa_gpio_id *pxa_id = (struct pxa_gpio_id *)id->driver_data;
 	int count = 0;

 	switch (pxa_id->type) {
 	case PXA25X_GPIO:
 	case PXA26X_GPIO:
 	case PXA27X_GPIO:
 	case PXA3XX_GPIO:
 	case PXA93X_GPIO:
 	case MMP_GPIO:
 	case MMP2_GPIO:
 	case PXA1928_GPIO:
 		gpio_type = pxa_id->type;
 		count = pxa_id->gpio_nums - 1;
 		break;
 	default:
 		count = -EINVAL;
 		break;
 	}
 	return count;
 }

 static int pxa_irq_domain_map(struct irq_domain *d, unsigned int irq,
 			      irq_hw_number_t hw)
 {
 	irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
 				 handle_edge_irq);
 	irq_set_chip_data(irq, d->host_data);
 	irq_set_noprobe(irq);
 	return 0;
 }

 const struct irq_domain_ops pxa_irq_domain_ops = {
 	.map	= pxa_irq_domain_map,
 	.xlate	= irq_domain_xlate_twocell,
 };

 #ifdef CONFIG_OF
 static const struct of_device_id pxa_gpio_dt_ids[] = {
 	{ .compatible = "intel,pxa25x-gpio",	.data = &pxa25x_id, },
 	{ .compatible = "intel,pxa26x-gpio",	.data = &pxa26x_id, },
 	{ .compatible = "intel,pxa27x-gpio",	.data = &pxa27x_id, },
 	{ .compatible = "intel,pxa3xx-gpio",	.data = &pxa3xx_id, },
 	{ .compatible = "marvell,pxa93x-gpio",	.data = &pxa93x_id, },
 	{ .compatible = "marvell,mmp-gpio",	.data = &mmp_id, },
 	{ .compatible = "marvell,mmp2-gpio",	.data = &mmp2_id, },
 	{ .compatible = "marvell,pxa1928-gpio",	.data = &pxa1928_id, },
 	{}
 };

 static int pxa_gpio_probe_dt(struct platform_device *pdev,
 			     struct pxa_gpio_chip *pchip)
 {
 	int nr_gpios;
 	const struct of_device_id *of_id =
 				of_match_device(pxa_gpio_dt_ids, &pdev->dev);
 	const struct pxa_gpio_id *gpio_id;

 	if (!of_id || !of_id->data) {
 		dev_err(&pdev->dev, "Failed to find gpio controller\n");
 		return -EFAULT;
 	}
 	gpio_id = of_id->data;
 	gpio_type = gpio_id->type;

 	nr_gpios = gpio_id->gpio_nums;
 	pxa_last_gpio = nr_gpios - 1;

 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, nr_gpios, 0);
 	if (irq_base < 0) {
 		dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
 		return irq_base;
 	}
 	return irq_base;
 }
 #else
 #define pxa_gpio_probe_dt(pdev, pchip)		(-1)
 #endif

 static int pxa_gpio_probe(struct platform_device *pdev)
 {
 	struct pxa_gpio_chip *pchip;
 	struct pxa_gpio_bank *c;
 	struct resource *res;
 	struct clk *clk;
 	struct pxa_gpio_platform_data *info;
 	void __iomem *gpio_reg_base;
 	int gpio, ret;
 	int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;

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

 	info = dev_get_platdata(&pdev->dev);
 	if (info) {
 		irq_base = info->irq_base;
 		if (irq_base <= 0)
 			return -EINVAL;
 		pxa_last_gpio = pxa_gpio_nums(pdev);
 		pchip->set_wake = info->gpio_set_wake;
 	} else {
 		irq_base = pxa_gpio_probe_dt(pdev, pchip);
 		if (irq_base < 0)
 			return -EINVAL;
 	}

 	if (!pxa_last_gpio)
 		return -EINVAL;

 	pchip->irqdomain = irq_domain_add_legacy(pdev->dev.of_node,
 						 pxa_last_gpio + 1, irq_base,
 						 0, &pxa_irq_domain_ops, pchip);
 	if (!pchip->irqdomain)
 		return -ENOMEM;

 	irq0 = platform_get_irq_byname(pdev, "gpio0");
 	irq1 = platform_get_irq_byname(pdev, "gpio1");
 	irq_mux = platform_get_irq_byname(pdev, "gpio_mux");
 	if ((irq0 > 0 && irq1 <= 0) || (irq0 <= 0 && irq1 > 0)
 		|| (irq_mux <= 0))
 		return -EINVAL;

 	pchip->irq0 = irq0;
 	pchip->irq1 = irq1;
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
 		return -EINVAL;
 	gpio_reg_base = devm_ioremap(&pdev->dev, res->start,
 				     resource_size(res));
 	if (!gpio_reg_base)
 		return -EINVAL;

 	if (irq0 > 0)
 		gpio_offset = 2;

 	clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "Error %ld to get gpio clock\n",
 			PTR_ERR(clk));
 		return PTR_ERR(clk);
 	}
 	ret = clk_prepare_enable(clk);
 	if (ret) {
 		clk_put(clk);
 		return ret;
 	}

 	/* Initialize GPIO chips */
 	ret = pxa_init_gpio_chip(pchip, pxa_last_gpio + 1, pdev->dev.of_node,
 				 gpio_reg_base);
 	if (ret) {
 		clk_put(clk);
 		return ret;
 	}

 	/* clear all GPIO edge detects */
 	for_each_gpio_bank(gpio, c, pchip) {
 		writel_relaxed(0, c->regbase + GFER_OFFSET);
 		writel_relaxed(0, c->regbase + GRER_OFFSET);
 		writel_relaxed(~0, c->regbase + GEDR_OFFSET);
 		/* unmask GPIO edge detect for AP side */
 		if (gpio_is_mmp_type(gpio_type))
 			writel_relaxed(~0, c->regbase + ED_MASK_OFFSET);
 	}

 	if (irq0 > 0) {
 		ret = devm_request_irq(&pdev->dev,
 				       irq0, pxa_gpio_direct_handler, 0,
 				       "gpio-0", pchip);
 		if (ret)
 			dev_err(&pdev->dev, "request of gpio0 irq failed: %d\n",
 				ret);
 	}
 	if (irq1 > 0) {
 		ret = devm_request_irq(&pdev->dev,
 				       irq1, pxa_gpio_direct_handler, 0,
 				       "gpio-1", pchip);
 		if (ret)
 			dev_err(&pdev->dev, "request of gpio1 irq failed: %d\n",
 				ret);
 	}
 	ret = devm_request_irq(&pdev->dev,
 			       irq_mux, pxa_gpio_demux_handler, 0,
 				       "gpio-mux", pchip);
 	if (ret)
 		dev_err(&pdev->dev, "request of gpio-mux irq failed: %d\n",
 				ret);

 	pxa_gpio_chip = pchip;

 	return 0;
 }

 static const struct platform_device_id gpio_id_table[] = {
 	{ "pxa25x-gpio",	(unsigned long)&pxa25x_id },
 	{ "pxa26x-gpio",	(unsigned long)&pxa26x_id },
 	{ "pxa27x-gpio",	(unsigned long)&pxa27x_id },
 	{ "pxa3xx-gpio",	(unsigned long)&pxa3xx_id },
 	{ "pxa93x-gpio",	(unsigned long)&pxa93x_id },
 	{ "mmp-gpio",		(unsigned long)&mmp_id },
 	{ "mmp2-gpio",		(unsigned long)&mmp2_id },
 	{ "pxa1928-gpio",	(unsigned long)&pxa1928_id },
 	{ },
 };

 static struct platform_driver pxa_gpio_driver = {
 	.probe		= pxa_gpio_probe,
 	.driver		= {
 		.name	= "pxa-gpio",
 		.of_match_table = of_match_ptr(pxa_gpio_dt_ids),
 	},
 	.id_table	= gpio_id_table,
 };

 static int __init pxa_gpio_legacy_init(void)
 {
 	if (of_have_populated_dt())
 		return 0;

 	return platform_driver_register(&pxa_gpio_driver);
 }
 postcore_initcall(pxa_gpio_legacy_init);

 static int __init pxa_gpio_dt_init(void)
 {
 	if (of_have_populated_dt())
 		return platform_driver_register(&pxa_gpio_driver);

 	return 0;
 }
 device_initcall(pxa_gpio_dt_init);

 #ifdef CONFIG_PM
 static int pxa_gpio_suspend(void)
 {
 	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
 	struct pxa_gpio_bank *c;
 	int gpio;

 	if (!pchip)
 		return 0;

 	for_each_gpio_bank(gpio, c, pchip) {
 		c->saved_gplr = readl_relaxed(c->regbase + GPLR_OFFSET);
 		c->saved_gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
 		c->saved_grer = readl_relaxed(c->regbase + GRER_OFFSET);
 		c->saved_gfer = readl_relaxed(c->regbase + GFER_OFFSET);

 		/* Clear GPIO transition detect bits */
 		writel_relaxed(0xffffffff, c->regbase + GEDR_OFFSET);
 	}
 	return 0;
 }

 static void pxa_gpio_resume(void)
 {
 	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
 	struct pxa_gpio_bank *c;
 	int gpio;

 	if (!pchip)
 		return;

 	for_each_gpio_bank(gpio, c, pchip) {
 		/* restore level with set/clear */
 		writel_relaxed(c->saved_gplr, c->regbase + GPSR_OFFSET);
 		writel_relaxed(~c->saved_gplr, c->regbase + GPCR_OFFSET);

 		writel_relaxed(c->saved_grer, c->regbase + GRER_OFFSET);
 		writel_relaxed(c->saved_gfer, c->regbase + GFER_OFFSET);
 		writel_relaxed(c->saved_gpdr, c->regbase + GPDR_OFFSET);
 	}
 }
 #else
 #define pxa_gpio_suspend	NULL
 #define pxa_gpio_resume		NULL
 #endif

 struct syscore_ops pxa_gpio_syscore_ops = {
 	.suspend	= pxa_gpio_suspend,
 	.resume		= pxa_gpio_resume,
 };

 static int __init pxa_gpio_sysinit(void)
 {
 	register_syscore_ops(&pxa_gpio_syscore_ops);
 	return 0;
 }
 postcore_initcall(pxa_gpio_sysinit);
	/*
	* linux/arch/arm/plat-pxa/gpio.c
	*
	* Generic PXA GPIO handling
	*
	* Author: Nicolas Pitre
	* Created: Jun 15, 2001
	* Copyright: MontaVista Software Inc.
	*
	* 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.
	*/
	#include <linux/module.h>
	#include <linux/clk.h>
	#include <linux/err.h>
	#include <linux/gpio.h>
	#include <linux/gpio-pxa.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/irqdomain.h>
	#include <linux/irqchip/chained_irq.h>
	#include <linux/io.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/pinctrl/consumer.h>
	#include <linux/platform_device.h>
	#include <linux/syscore_ops.h>
	#include <linux/slab.h>

	/*
	* We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
	* one set of registers. The register offsets are organized below:
	*
	* GPLR GPDR GPSR GPCR GRER GFER GEDR
	* BANK 0 - 0x0000 0x000C 0x0018 0x0024 0x0030 0x003C 0x0048
	* BANK 1 - 0x0004 0x0010 0x001C 0x0028 0x0034 0x0040 0x004C
	* BANK 2 - 0x0008 0x0014 0x0020 0x002C 0x0038 0x0044 0x0050
	*
	* BANK 3 - 0x0100 0x010C 0x0118 0x0124 0x0130 0x013C 0x0148
	* BANK 4 - 0x0104 0x0110 0x011C 0x0128 0x0134 0x0140 0x014C
	* BANK 5 - 0x0108 0x0114 0x0120 0x012C 0x0138 0x0144 0x0150
	*
	* BANK 6 - 0x0200 0x020C 0x0218 0x0224 0x0230 0x023C 0x0248
	*
	* NOTE:
	* BANK 3 is only available on PXA27x and later processors.
	* BANK 4 and 5 are only available on PXA935, PXA1928
	* BANK 6 is only available on PXA1928
	*/

	#define GPLR_OFFSET 0x00
	#define GPDR_OFFSET 0x0C
	#define GPSR_OFFSET 0x18
	#define GPCR_OFFSET 0x24
	#define GRER_OFFSET 0x30
	#define GFER_OFFSET 0x3C
	#define GEDR_OFFSET 0x48
	#define GAFR_OFFSET 0x54
	#define ED_MASK_OFFSET 0x9C /* GPIO edge detection for AP side */

	#define BANK_OFF(n) (((n) / 3) << 8) + (((n) % 3) << 2)

	int pxa_last_gpio;
	static int irq_base;

	struct pxa_gpio_bank {
	void __iomem *regbase;
	unsigned long irq_mask;
	unsigned long irq_edge_rise;
	unsigned long irq_edge_fall;

	#ifdef CONFIG_PM
	unsigned long saved_gplr;
	unsigned long saved_gpdr;
	unsigned long saved_grer;
	unsigned long saved_gfer;
	#endif
	};

	struct pxa_gpio_chip {
	struct device *dev;
	struct gpio_chip chip;
	struct pxa_gpio_bank *banks;
	struct irq_domain *irqdomain;

	int irq0;
	int irq1;
	int (*set_wake)(unsigned int gpio, unsigned int on);
	};

	enum pxa_gpio_type {
	PXA25X_GPIO = 0,
	PXA26X_GPIO,
	PXA27X_GPIO,
	PXA3XX_GPIO,
	PXA93X_GPIO,
	MMP_GPIO = 0x10,
	MMP2_GPIO,
	PXA1928_GPIO,
	};

	struct pxa_gpio_id {
	enum pxa_gpio_type type;
	int gpio_nums;
	};

	static DEFINE_SPINLOCK(gpio_lock);
	static struct pxa_gpio_chip *pxa_gpio_chip;
	static enum pxa_gpio_type gpio_type;

	static struct pxa_gpio_id pxa25x_id = {
	.type = PXA25X_GPIO,
	.gpio_nums = 85,
	};

	static struct pxa_gpio_id pxa26x_id = {
	.type = PXA26X_GPIO,
	.gpio_nums = 90,
	};

	static struct pxa_gpio_id pxa27x_id = {
	.type = PXA27X_GPIO,
	.gpio_nums = 121,
	};

	static struct pxa_gpio_id pxa3xx_id = {
	.type = PXA3XX_GPIO,
	.gpio_nums = 128,
	};

	static struct pxa_gpio_id pxa93x_id = {
	.type = PXA93X_GPIO,
	.gpio_nums = 192,
	};

	static struct pxa_gpio_id mmp_id = {
	.type = MMP_GPIO,
	.gpio_nums = 128,
	};

	static struct pxa_gpio_id mmp2_id = {
	.type = MMP2_GPIO,
	.gpio_nums = 192,
	};

	static struct pxa_gpio_id pxa1928_id = {
	.type = PXA1928_GPIO,
	.gpio_nums = 224,
	};

	#define for_each_gpio_bank(i, b, pc) \
	for (i = 0, b = pc->banks; i <= pxa_last_gpio; i += 32, b++)

	static inline struct pxa_gpio_chip chip_to_pxachip(struct gpio_chip c)
	{
	struct pxa_gpio_chip *pxa_chip = gpiochip_get_data(c);

	return pxa_chip;
	}

	static inline void __iomem gpio_bank_base(struct gpio_chip c, int gpio)
	{
	struct pxa_gpio_chip *p = gpiochip_get_data(c);
	struct pxa_gpio_bank *bank = p->banks + (gpio / 32);

	return bank->regbase;
	}

	static inline struct pxa_gpio_bank gpio_to_pxabank(struct gpio_chip c,
	unsigned gpio)
	{
	return chip_to_pxachip(c)->banks + gpio / 32;
	}

	static inline int gpio_is_pxa_type(int type)
	{
	return (type & MMP_GPIO) == 0;
	}

	static inline int gpio_is_mmp_type(int type)
	{
	return (type & MMP_GPIO) != 0;
	}

	/* GPIO86/87/88/89 on PXA26x have their direction bits in PXA_GPDR(2 inverted,
	* as well as their Alternate Function value being '1' for GPIO in GAFRx.
	*/
	static inline int __gpio_is_inverted(int gpio)
	{
	if ((gpio_type == PXA26X_GPIO) && (gpio > 85))
	return 1;
	return 0;
	}

	/*
	* On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
	* function of a GPIO, and GPDRx cannot be altered once configured. It
	* is attributed as "occupied" here (I know this terminology isn't
	* accurate, you are welcome to propose a better one :-)
	*/
	static inline int __gpio_is_occupied(struct pxa_gpio_chip *pchip, unsigned gpio)
	{
	void __iomem *base;
	unsigned long gafr = 0, gpdr = 0;
	int ret, af = 0, dir = 0;

	base = gpio_bank_base(&pchip->chip, gpio);
	gpdr = readl_relaxed(base + GPDR_OFFSET);

	switch (gpio_type) {
	case PXA25X_GPIO:
	case PXA26X_GPIO:
	case PXA27X_GPIO:
	gafr = readl_relaxed(base + GAFR_OFFSET);
	af = (gafr >> ((gpio & 0xf) * 2)) & 0x3;
	dir = gpdr & GPIO_bit(gpio);

	if (__gpio_is_inverted(gpio))
	ret = (af != 1) \|\| (dir == 0);
	else
	ret = (af != 0) \|\| (dir != 0);
	break;
	default:
	ret = gpdr & GPIO_bit(gpio);
	break;
	}
	return ret;
	}

	int pxa_irq_to_gpio(int irq)
	{
	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
	int irq_gpio0;

	irq_gpio0 = irq_find_mapping(pchip->irqdomain, 0);
	if (irq_gpio0 > 0)
	return irq - irq_gpio0;

	return irq_gpio0;
	}

	static int pxa_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
	{
	struct pxa_gpio_chip *pchip = chip_to_pxachip(chip);

	return irq_find_mapping(pchip->irqdomain, offset);
	}

	static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
	{
	void __iomem *base = gpio_bank_base(chip, offset);
	uint32_t value, mask = GPIO_bit(offset);
	unsigned long flags;
	int ret;

	ret = pinctrl_gpio_direction_input(chip->base + offset);
	if (!ret)
	return 0;

	spin_lock_irqsave(&gpio_lock, flags);

	value = readl_relaxed(base + GPDR_OFFSET);
	if (__gpio_is_inverted(chip->base + offset))
	value \|= mask;
	else
	value &= ~mask;
	writel_relaxed(value, base + GPDR_OFFSET);

	spin_unlock_irqrestore(&gpio_lock, flags);
	return 0;
	}

	static int pxa_gpio_direction_output(struct gpio_chip *chip,
	unsigned offset, int value)
	{
	void __iomem *base = gpio_bank_base(chip, offset);
	uint32_t tmp, mask = GPIO_bit(offset);
	unsigned long flags;
	int ret;

	writel_relaxed(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));

	ret = pinctrl_gpio_direction_output(chip->base + offset);
	if (ret)
	return ret;

	spin_lock_irqsave(&gpio_lock, flags);

	tmp = readl_relaxed(base + GPDR_OFFSET);
	if (__gpio_is_inverted(chip->base + offset))
	tmp &= ~mask;
	else
	tmp \|= mask;
	writel_relaxed(tmp, base + GPDR_OFFSET);

	spin_unlock_irqrestore(&gpio_lock, flags);
	return 0;
	}

	static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
	{
	void __iomem *base = gpio_bank_base(chip, offset);
	u32 gplr = readl_relaxed(base + GPLR_OFFSET);

	return !!(gplr & GPIO_bit(offset));
	}

	static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
	{
	void __iomem *base = gpio_bank_base(chip, offset);

	writel_relaxed(GPIO_bit(offset),
	base + (value ? GPSR_OFFSET : GPCR_OFFSET));
	}

	#ifdef CONFIG_OF_GPIO
	static int pxa_gpio_of_xlate(struct gpio_chip *gc,
	const struct of_phandle_args *gpiospec,
	u32 *flags)
	{
	if (gpiospec->args[0] > pxa_last_gpio)
	return -EINVAL;

	if (flags)
	*flags = gpiospec->args[1];

	return gpiospec->args[0];
	}
	#endif

	static int pxa_gpio_request(struct gpio_chip *chip, unsigned int offset)
	{
	return pinctrl_request_gpio(chip->base + offset);
	}

	static void pxa_gpio_free(struct gpio_chip *chip, unsigned int offset)
	{
	pinctrl_free_gpio(chip->base + offset);
	}

	static int pxa_init_gpio_chip(struct pxa_gpio_chip *pchip, int ngpio,
	struct device_node np, void __iomem regbase)
	{
	int i, gpio, nbanks = DIV_ROUND_UP(ngpio, 32);
	struct pxa_gpio_bank *bank;

	pchip->banks = devm_kcalloc(pchip->dev, nbanks, sizeof(*pchip->banks),
	GFP_KERNEL);
	if (!pchip->banks)
	return -ENOMEM;

	pchip->chip.label = "gpio-pxa";
	pchip->chip.direction_input = pxa_gpio_direction_input;
	pchip->chip.direction_output = pxa_gpio_direction_output;
	pchip->chip.get = pxa_gpio_get;
	pchip->chip.set = pxa_gpio_set;
	pchip->chip.to_irq = pxa_gpio_to_irq;
	pchip->chip.ngpio = ngpio;
	pchip->chip.request = pxa_gpio_request;
	pchip->chip.free = pxa_gpio_free;
	#ifdef CONFIG_OF_GPIO
	pchip->chip.of_node = np;
	pchip->chip.of_xlate = pxa_gpio_of_xlate;
	pchip->chip.of_gpio_n_cells = 2;
	#endif

	for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
	bank = pchip->banks + i;
	bank->regbase = regbase + BANK_OFF(i);
	}

	return gpiochip_add_data(&pchip->chip, pchip);
	}

	/* Update only those GRERx and GFERx edge detection register bits if those
	* bits are set in c->irq_mask
	*/
	static inline void update_edge_detect(struct pxa_gpio_bank *c)
	{
	uint32_t grer, gfer;

	grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~c->irq_mask;
	gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~c->irq_mask;
	grer \|= c->irq_edge_rise & c->irq_mask;
	gfer \|= c->irq_edge_fall & c->irq_mask;
	writel_relaxed(grer, c->regbase + GRER_OFFSET);
	writel_relaxed(gfer, c->regbase + GFER_OFFSET);
	}

	static int pxa_gpio_irq_type(struct irq_data *d, unsigned int type)
	{
	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
	unsigned int gpio = irqd_to_hwirq(d);
	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);
	unsigned long gpdr, mask = GPIO_bit(gpio);

	if (type == IRQ_TYPE_PROBE) {
	/* Don't mess with enabled GPIOs using preconfigured edges or
	* GPIOs set to alternate function or to output during probe
	*/
	if ((c->irq_edge_rise \| c->irq_edge_fall) & GPIO_bit(gpio))
	return 0;

	if (__gpio_is_occupied(pchip, gpio))
	return 0;

	type = IRQ_TYPE_EDGE_RISING \| IRQ_TYPE_EDGE_FALLING;
	}

	gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);

	if (__gpio_is_inverted(gpio))
	writel_relaxed(gpdr \| mask, c->regbase + GPDR_OFFSET);
	else
	writel_relaxed(gpdr & ~mask, c->regbase + GPDR_OFFSET);

	if (type & IRQ_TYPE_EDGE_RISING)
	c->irq_edge_rise \|= mask;
	else
	c->irq_edge_rise &= ~mask;

	if (type & IRQ_TYPE_EDGE_FALLING)
	c->irq_edge_fall \|= mask;
	else
	c->irq_edge_fall &= ~mask;

	update_edge_detect(c);

	pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, d->irq, gpio,
	((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
	((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
	return 0;
	}

	static irqreturn_t pxa_gpio_demux_handler(int in_irq, void *d)
	{
	int loop, gpio, n, handled = 0;
	unsigned long gedr;
	struct pxa_gpio_chip *pchip = d;
	struct pxa_gpio_bank *c;

	do {
	loop = 0;
	for_each_gpio_bank(gpio, c, pchip) {
	gedr = readl_relaxed(c->regbase + GEDR_OFFSET);
	gedr = gedr & c->irq_mask;
	writel_relaxed(gedr, c->regbase + GEDR_OFFSET);

	for_each_set_bit(n, &gedr, BITS_PER_LONG) {
	loop = 1;

	generic_handle_irq(
	irq_find_mapping(pchip->irqdomain,
	gpio + n));
	}
	}
	handled += loop;
	} while (loop);

	return handled ? IRQ_HANDLED : IRQ_NONE;
	}

	static irqreturn_t pxa_gpio_direct_handler(int in_irq, void *d)
	{
	struct pxa_gpio_chip *pchip = d;

	if (in_irq == pchip->irq0) {
	generic_handle_irq(irq_find_mapping(pchip->irqdomain, 0));
	} else if (in_irq == pchip->irq1) {
	generic_handle_irq(irq_find_mapping(pchip->irqdomain, 1));
	} else {
	pr_err("%s() unknown irq %d\n", __func__, in_irq);
	return IRQ_NONE;
	}
	return IRQ_HANDLED;
	}

	static void pxa_ack_muxed_gpio(struct irq_data *d)
	{
	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
	unsigned int gpio = irqd_to_hwirq(d);
	void __iomem *base = gpio_bank_base(&pchip->chip, gpio);

	writel_relaxed(GPIO_bit(gpio), base + GEDR_OFFSET);
	}

	static void pxa_mask_muxed_gpio(struct irq_data *d)
	{
	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
	unsigned int gpio = irqd_to_hwirq(d);
	struct pxa_gpio_bank *b = gpio_to_pxabank(&pchip->chip, gpio);
	void __iomem *base = gpio_bank_base(&pchip->chip, gpio);
	uint32_t grer, gfer;

	b->irq_mask &= ~GPIO_bit(gpio);

	grer = readl_relaxed(base + GRER_OFFSET) & ~GPIO_bit(gpio);
	gfer = readl_relaxed(base + GFER_OFFSET) & ~GPIO_bit(gpio);
	writel_relaxed(grer, base + GRER_OFFSET);
	writel_relaxed(gfer, base + GFER_OFFSET);
	}

	static int pxa_gpio_set_wake(struct irq_data *d, unsigned int on)
	{
	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
	unsigned int gpio = irqd_to_hwirq(d);

	if (pchip->set_wake)
	return pchip->set_wake(gpio, on);
	else
	return 0;
	}

	static void pxa_unmask_muxed_gpio(struct irq_data *d)
	{
	struct pxa_gpio_chip *pchip = irq_data_get_irq_chip_data(d);
	unsigned int gpio = irqd_to_hwirq(d);
	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);

	c->irq_mask \|= GPIO_bit(gpio);
	update_edge_detect(c);
	}

	static struct irq_chip pxa_muxed_gpio_chip = {
	.name = "GPIO",
	.irq_ack = pxa_ack_muxed_gpio,
	.irq_mask = pxa_mask_muxed_gpio,
	.irq_unmask = pxa_unmask_muxed_gpio,
	.irq_set_type = pxa_gpio_irq_type,
	.irq_set_wake = pxa_gpio_set_wake,
	};

	static int pxa_gpio_nums(struct platform_device *pdev)
	{
	const struct platform_device_id *id = platform_get_device_id(pdev);
	struct pxa_gpio_id pxa_id = (struct pxa_gpio_id )id->driver_data;
	int count = 0;

	switch (pxa_id->type) {
	case PXA25X_GPIO:
	case PXA26X_GPIO:
	case PXA27X_GPIO:
	case PXA3XX_GPIO:
	case PXA93X_GPIO:
	case MMP_GPIO:
	case MMP2_GPIO:
	case PXA1928_GPIO:
	gpio_type = pxa_id->type;
	count = pxa_id->gpio_nums - 1;
	break;
	default:
	count = -EINVAL;
	break;
	}
	return count;
	}

	static int pxa_irq_domain_map(struct irq_domain *d, unsigned int irq,
	irq_hw_number_t hw)
	{
	irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
	handle_edge_irq);
	irq_set_chip_data(irq, d->host_data);
	irq_set_noprobe(irq);
	return 0;
	}

	const struct irq_domain_ops pxa_irq_domain_ops = {
	.map = pxa_irq_domain_map,
	.xlate = irq_domain_xlate_twocell,
	};

	#ifdef CONFIG_OF
	static const struct of_device_id pxa_gpio_dt_ids[] = {
	{ .compatible = "intel,pxa25x-gpio", .data = &pxa25x_id, },
	{ .compatible = "intel,pxa26x-gpio", .data = &pxa26x_id, },
	{ .compatible = "intel,pxa27x-gpio", .data = &pxa27x_id, },
	{ .compatible = "intel,pxa3xx-gpio", .data = &pxa3xx_id, },
	{ .compatible = "marvell,pxa93x-gpio", .data = &pxa93x_id, },
	{ .compatible = "marvell,mmp-gpio", .data = &mmp_id, },
	{ .compatible = "marvell,mmp2-gpio", .data = &mmp2_id, },
	{ .compatible = "marvell,pxa1928-gpio", .data = &pxa1928_id, },
	{}
	};

	static int pxa_gpio_probe_dt(struct platform_device *pdev,
	struct pxa_gpio_chip *pchip)
	{
	int nr_gpios;
	const struct of_device_id *of_id =
	of_match_device(pxa_gpio_dt_ids, &pdev->dev);
	const struct pxa_gpio_id *gpio_id;

	if (!of_id \|\| !of_id->data) {
	dev_err(&pdev->dev, "Failed to find gpio controller\n");
	return -EFAULT;
	}
	gpio_id = of_id->data;
	gpio_type = gpio_id->type;

	nr_gpios = gpio_id->gpio_nums;
	pxa_last_gpio = nr_gpios - 1;

	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, nr_gpios, 0);
	if (irq_base < 0) {
	dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
	return irq_base;
	}
	return irq_base;
	}
	#else
	#define pxa_gpio_probe_dt(pdev, pchip) (-1)
	#endif

	static int pxa_gpio_probe(struct platform_device *pdev)
	{
	struct pxa_gpio_chip *pchip;
	struct pxa_gpio_bank *c;
	struct resource *res;
	struct clk *clk;
	struct pxa_gpio_platform_data *info;
	void __iomem *gpio_reg_base;
	int gpio, ret;
	int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;

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

	info = dev_get_platdata(&pdev->dev);
	if (info) {
	irq_base = info->irq_base;
	if (irq_base <= 0)
	return -EINVAL;
	pxa_last_gpio = pxa_gpio_nums(pdev);
	pchip->set_wake = info->gpio_set_wake;
	} else {
	irq_base = pxa_gpio_probe_dt(pdev, pchip);
	if (irq_base < 0)
	return -EINVAL;
	}

	if (!pxa_last_gpio)
	return -EINVAL;

	pchip->irqdomain = irq_domain_add_legacy(pdev->dev.of_node,
	pxa_last_gpio + 1, irq_base,
	0, &pxa_irq_domain_ops, pchip);
	if (!pchip->irqdomain)
	return -ENOMEM;

	irq0 = platform_get_irq_byname(pdev, "gpio0");
	irq1 = platform_get_irq_byname(pdev, "gpio1");
	irq_mux = platform_get_irq_byname(pdev, "gpio_mux");
	if ((irq0 > 0 && irq1 <= 0) \|\| (irq0 <= 0 && irq1 > 0)
	\|\| (irq_mux <= 0))
	return -EINVAL;

	pchip->irq0 = irq0;
	pchip->irq1 = irq1;
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
	return -EINVAL;
	gpio_reg_base = devm_ioremap(&pdev->dev, res->start,
	resource_size(res));
	if (!gpio_reg_base)
	return -EINVAL;

	if (irq0 > 0)
	gpio_offset = 2;

	clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(clk)) {
	dev_err(&pdev->dev, "Error %ld to get gpio clock\n",
	PTR_ERR(clk));
	return PTR_ERR(clk);
	}
	ret = clk_prepare_enable(clk);
	if (ret) {
	clk_put(clk);
	return ret;
	}

	/* Initialize GPIO chips */
	ret = pxa_init_gpio_chip(pchip, pxa_last_gpio + 1, pdev->dev.of_node,
	gpio_reg_base);
	if (ret) {
	clk_put(clk);
	return ret;
	}

	/* clear all GPIO edge detects */
	for_each_gpio_bank(gpio, c, pchip) {
	writel_relaxed(0, c->regbase + GFER_OFFSET);
	writel_relaxed(0, c->regbase + GRER_OFFSET);
	writel_relaxed(~0, c->regbase + GEDR_OFFSET);
	/* unmask GPIO edge detect for AP side */
	if (gpio_is_mmp_type(gpio_type))
	writel_relaxed(~0, c->regbase + ED_MASK_OFFSET);
	}

	if (irq0 > 0) {
	ret = devm_request_irq(&pdev->dev,
	irq0, pxa_gpio_direct_handler, 0,
	"gpio-0", pchip);
	if (ret)
	dev_err(&pdev->dev, "request of gpio0 irq failed: %d\n",
	ret);
	}
	if (irq1 > 0) {
	ret = devm_request_irq(&pdev->dev,
	irq1, pxa_gpio_direct_handler, 0,
	"gpio-1", pchip);
	if (ret)
	dev_err(&pdev->dev, "request of gpio1 irq failed: %d\n",
	ret);
	}
	ret = devm_request_irq(&pdev->dev,
	irq_mux, pxa_gpio_demux_handler, 0,
	"gpio-mux", pchip);
	if (ret)
	dev_err(&pdev->dev, "request of gpio-mux irq failed: %d\n",
	ret);

	pxa_gpio_chip = pchip;

	return 0;
	}

	static const struct platform_device_id gpio_id_table[] = {
	{ "pxa25x-gpio", (unsigned long)&pxa25x_id },
	{ "pxa26x-gpio", (unsigned long)&pxa26x_id },
	{ "pxa27x-gpio", (unsigned long)&pxa27x_id },
	{ "pxa3xx-gpio", (unsigned long)&pxa3xx_id },
	{ "pxa93x-gpio", (unsigned long)&pxa93x_id },
	{ "mmp-gpio", (unsigned long)&mmp_id },
	{ "mmp2-gpio", (unsigned long)&mmp2_id },
	{ "pxa1928-gpio", (unsigned long)&pxa1928_id },
	{ },
	};

	static struct platform_driver pxa_gpio_driver = {
	.probe = pxa_gpio_probe,
	.driver = {
	.name = "pxa-gpio",
	.of_match_table = of_match_ptr(pxa_gpio_dt_ids),
	},
	.id_table = gpio_id_table,
	};

	static int __init pxa_gpio_legacy_init(void)
	{
	if (of_have_populated_dt())
	return 0;

	return platform_driver_register(&pxa_gpio_driver);
	}
	postcore_initcall(pxa_gpio_legacy_init);

	static int __init pxa_gpio_dt_init(void)
	{
	if (of_have_populated_dt())
	return platform_driver_register(&pxa_gpio_driver);

	return 0;
	}
	device_initcall(pxa_gpio_dt_init);

	#ifdef CONFIG_PM
	static int pxa_gpio_suspend(void)
	{
	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
	struct pxa_gpio_bank *c;
	int gpio;

	if (!pchip)
	return 0;

	for_each_gpio_bank(gpio, c, pchip) {
	c->saved_gplr = readl_relaxed(c->regbase + GPLR_OFFSET);
	c->saved_gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
	c->saved_grer = readl_relaxed(c->regbase + GRER_OFFSET);
	c->saved_gfer = readl_relaxed(c->regbase + GFER_OFFSET);

	/* Clear GPIO transition detect bits */
	writel_relaxed(0xffffffff, c->regbase + GEDR_OFFSET);
	}
	return 0;
	}

	static void pxa_gpio_resume(void)
	{
	struct pxa_gpio_chip *pchip = pxa_gpio_chip;
	struct pxa_gpio_bank *c;
	int gpio;

	if (!pchip)
	return;

	for_each_gpio_bank(gpio, c, pchip) {
	/* restore level with set/clear */
	writel_relaxed(c->saved_gplr, c->regbase + GPSR_OFFSET);
	writel_relaxed(~c->saved_gplr, c->regbase + GPCR_OFFSET);

	writel_relaxed(c->saved_grer, c->regbase + GRER_OFFSET);
	writel_relaxed(c->saved_gfer, c->regbase + GFER_OFFSET);
	writel_relaxed(c->saved_gpdr, c->regbase + GPDR_OFFSET);
	}
	}
	#else
	#define pxa_gpio_suspend NULL
	#define pxa_gpio_resume NULL
	#endif

	struct syscore_ops pxa_gpio_syscore_ops = {
	.suspend = pxa_gpio_suspend,
	.resume = pxa_gpio_resume,
	};

	static int __init pxa_gpio_sysinit(void)
	{
	register_syscore_ops(&pxa_gpio_syscore_ops);
	return 0;
	}
	postcore_initcall(pxa_gpio_sysinit);