drivers/gpio/gpio-langwell.c - kernel/msm-4.9 - Gitiles

 /*
  * Moorestown platform Langwell chip GPIO driver
  *
  * Copyright (c) 2008 - 2009,  Intel Corporation.
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

 /* Supports:
  * Moorestown platform Langwell chip.
  * Medfield platform Penwell chip.
  * Whitney point.
  */

 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/stddef.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/gpio.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
 #include <linux/irqdomain.h>

 /*
  * Langwell chip has 64 pins and thus there are 2 32bit registers to control
  * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
  * registers to control them, so we only define the order here instead of a
  * structure, to get a bit offset for a pin (use GPDR as an example):
  *
  * nreg = ngpio / 32;
  * reg = offset / 32;
  * bit = offset % 32;
  * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
  *
  * so the bit of reg_addr is to control pin offset's GPDR feature
 */

 enum GPIO_REG {
 	GPLR = 0,	/* pin level read-only */
 	GPDR,		/* pin direction */
 	GPSR,		/* pin set */
 	GPCR,		/* pin clear */
 	GRER,		/* rising edge detect */
 	GFER,		/* falling edge detect */
 	GEDR,		/* edge detect result */
 	GAFR,		/* alt function */
 };

 struct lnw_gpio {
 	struct gpio_chip		chip;
 	void				*reg_base;
 	spinlock_t			lock;
 	struct pci_dev			*pdev;
 	struct irq_domain		*domain;
 };

 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
 			enum GPIO_REG reg_type)
 {
 	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 	unsigned nreg = chip->ngpio / 32;
 	u8 reg = offset / 32;
 	void __iomem *ptr;

 	ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
 	return ptr;
 }

 static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
 				   enum GPIO_REG reg_type)
 {
 	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 	unsigned nreg = chip->ngpio / 32;
 	u8 reg = offset / 16;
 	void __iomem *ptr;

 	ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
 	return ptr;
 }

 static int lnw_gpio_request(struct gpio_chip *chip, unsigned offset)
 {
 	void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
 	u32 value = readl(gafr);
 	int shift = (offset % 16) << 1, af = (value >> shift) & 3;

 	if (af) {
 		value &= ~(3 << shift);
 		writel(value, gafr);
 	}
 	return 0;
 }

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

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

 static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
 	void __iomem *gpsr, *gpcr;

 	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);
 	}
 }

 static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 {
 	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 	u32 value;
 	unsigned long flags;

 	if (lnw->pdev)
 		pm_runtime_get(&lnw->pdev->dev);

 	spin_lock_irqsave(&lnw->lock, flags);
 	value = readl(gpdr);
 	value &= ~BIT(offset % 32);
 	writel(value, gpdr);
 	spin_unlock_irqrestore(&lnw->lock, flags);

 	if (lnw->pdev)
 		pm_runtime_put(&lnw->pdev->dev);

 	return 0;
 }

 static int lnw_gpio_direction_output(struct gpio_chip *chip,
 			unsigned offset, int value)
 {
 	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 	unsigned long flags;

 	lnw_gpio_set(chip, offset, value);

 	if (lnw->pdev)
 		pm_runtime_get(&lnw->pdev->dev);

 	spin_lock_irqsave(&lnw->lock, flags);
 	value = readl(gpdr);
 	value |= BIT(offset % 32);
 	writel(value, gpdr);
 	spin_unlock_irqrestore(&lnw->lock, flags);

 	if (lnw->pdev)
 		pm_runtime_put(&lnw->pdev->dev);

 	return 0;
 }

 static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
 	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 	return irq_create_mapping(lnw->domain, offset);
 }

 static int lnw_irq_type(struct irq_data *d, unsigned type)
 {
 	struct lnw_gpio *lnw = irq_data_get_irq_chip_data(d);
 	u32 gpio = irqd_to_hwirq(d);
 	unsigned long flags;
 	u32 value;
 	void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
 	void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);

 	if (gpio >= lnw->chip.ngpio)
 		return -EINVAL;

 	if (lnw->pdev)
 		pm_runtime_get(&lnw->pdev->dev);

 	spin_lock_irqsave(&lnw->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);
 	spin_unlock_irqrestore(&lnw->lock, flags);

 	if (lnw->pdev)
 		pm_runtime_put(&lnw->pdev->dev);

 	return 0;
 }

 static void lnw_irq_unmask(struct irq_data *d)
 {
 }

 static void lnw_irq_mask(struct irq_data *d)
 {
 }

 static struct irq_chip lnw_irqchip = {
 	.name		= "LNW-GPIO",
 	.irq_mask	= lnw_irq_mask,
 	.irq_unmask	= lnw_irq_unmask,
 	.irq_set_type	= lnw_irq_type,
 };

 static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = {   /* pin number */
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
 	{ 0, }
 };
 MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);

 static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
 {
 	struct irq_data *data = irq_desc_get_irq_data(desc);
 	struct lnw_gpio *lnw = irq_data_get_irq_handler_data(data);
 	struct irq_chip *chip = irq_data_get_irq_chip(data);
 	u32 base, gpio, mask;
 	unsigned long pending;
 	void __iomem *gedr;

 	/* check GPIO controller to check which pin triggered the interrupt */
 	for (base = 0; base < lnw->chip.ngpio; base += 32) {
 		gedr = gpio_reg(&lnw->chip, base, GEDR);
 		while ((pending = readl(gedr))) {
 			gpio = __ffs(pending);
 			mask = BIT(gpio);
 			/* Clear before handling so we can't lose an edge */
 			writel(mask, gedr);
 			generic_handle_irq(irq_find_mapping(lnw->domain,
 							    base + gpio));
 		}
 	}

 	chip->irq_eoi(data);
 }

 static void lnw_irq_init_hw(struct lnw_gpio *lnw)
 {
 	void __iomem *reg;
 	unsigned base;

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

 static int lnw_gpio_irq_map(struct irq_domain *d, unsigned int virq,
 			    irq_hw_number_t hw)
 {
 	struct lnw_gpio *lnw = d->host_data;

 	irq_set_chip_and_handler_name(virq, &lnw_irqchip, handle_simple_irq,
 				      "demux");
 	irq_set_chip_data(virq, lnw);
 	irq_set_irq_type(virq, IRQ_TYPE_NONE);

 	return 0;
 }

 static const struct irq_domain_ops lnw_gpio_irq_ops = {
 	.map = lnw_gpio_irq_map,
 	.xlate = irq_domain_xlate_twocell,
 };

 #ifdef CONFIG_PM
 static int lnw_gpio_runtime_resume(struct device *dev)
 {
 	return 0;
 }

 static int lnw_gpio_runtime_suspend(struct device *dev)
 {
 	return 0;
 }

 static int lnw_gpio_runtime_idle(struct device *dev)
 {
 	int err = pm_schedule_suspend(dev, 500);

 	if (!err)
 		return 0;

 	return -EBUSY;
 }

 #else
 #define lnw_gpio_runtime_suspend	NULL
 #define lnw_gpio_runtime_resume		NULL
 #define lnw_gpio_runtime_idle		NULL
 #endif

 static const struct dev_pm_ops lnw_gpio_pm_ops = {
 	.runtime_suspend = lnw_gpio_runtime_suspend,
 	.runtime_resume = lnw_gpio_runtime_resume,
 	.runtime_idle = lnw_gpio_runtime_idle,
 };

 static int lnw_gpio_probe(struct pci_dev *pdev,
 			const struct pci_device_id *id)
 {
 	void *base;
 	resource_size_t start, len;
 	struct lnw_gpio *lnw;
 	u32 gpio_base;
 	int retval;
 	int ngpio = id->driver_data;

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

 	retval = pci_request_regions(pdev, "langwell_gpio");
 	if (retval) {
 		dev_err(&pdev->dev, "error requesting resources\n");
 		goto err2;
 	}
 	/* get the gpio_base from bar1 */
 	start = pci_resource_start(pdev, 1);
 	len = pci_resource_len(pdev, 1);
 	base = ioremap_nocache(start, len);
 	if (!base) {
 		dev_err(&pdev->dev, "error mapping bar1\n");
 		retval = -EFAULT;
 		goto err3;
 	}
 	gpio_base = *((u32 *)base + 1);
 	/* release the IO mapping, since we already get the info from bar1 */
 	iounmap(base);
 	/* get the register base from bar0 */
 	start = pci_resource_start(pdev, 0);
 	len = pci_resource_len(pdev, 0);
 	base = devm_ioremap_nocache(&pdev->dev, start, len);
 	if (!base) {
 		dev_err(&pdev->dev, "error mapping bar0\n");
 		retval = -EFAULT;
 		goto err3;
 	}

 	lnw = devm_kzalloc(&pdev->dev, sizeof(struct lnw_gpio), GFP_KERNEL);
 	if (!lnw) {
 		dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
 		retval = -ENOMEM;
 		goto err3;
 	}

 	lnw->domain = irq_domain_add_linear(pdev->dev.of_node, ngpio,
 					    &lnw_gpio_irq_ops, lnw);
 	if (!lnw->domain) {
 		retval = -ENOMEM;
 		goto err3;
 	}

 	lnw->reg_base = base;
 	lnw->chip.label = dev_name(&pdev->dev);
 	lnw->chip.request = lnw_gpio_request;
 	lnw->chip.direction_input = lnw_gpio_direction_input;
 	lnw->chip.direction_output = lnw_gpio_direction_output;
 	lnw->chip.get = lnw_gpio_get;
 	lnw->chip.set = lnw_gpio_set;
 	lnw->chip.to_irq = lnw_gpio_to_irq;
 	lnw->chip.base = gpio_base;
 	lnw->chip.ngpio = ngpio;
 	lnw->chip.can_sleep = 0;
 	lnw->pdev = pdev;
 	pci_set_drvdata(pdev, lnw);
 	retval = gpiochip_add(&lnw->chip);
 	if (retval) {
 		dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
 		goto err3;
 	}

 	lnw_irq_init_hw(lnw);

 	irq_set_handler_data(pdev->irq, lnw);
 	irq_set_chained_handler(pdev->irq, lnw_irq_handler);

 	spin_lock_init(&lnw->lock);

 	pm_runtime_put_noidle(&pdev->dev);
 	pm_runtime_allow(&pdev->dev);

 	return 0;

 err3:
 	pci_release_regions(pdev);
 err2:
 	pci_disable_device(pdev);
 	return retval;
 }

 static struct pci_driver lnw_gpio_driver = {
 	.name		= "langwell_gpio",
 	.id_table	= lnw_gpio_ids,
 	.probe		= lnw_gpio_probe,
 	.driver		= {
 		.pm	= &lnw_gpio_pm_ops,
 	},
 };


 static int wp_gpio_probe(struct platform_device *pdev)
 {
 	struct lnw_gpio *lnw;
 	struct gpio_chip *gc;
 	struct resource *rc;
 	int retval = 0;

 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!rc)
 		return -EINVAL;

 	lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
 	if (!lnw) {
 		dev_err(&pdev->dev,
 			"can't allocate whitneypoint_gpio chip data\n");
 		return -ENOMEM;
 	}
 	lnw->reg_base = ioremap_nocache(rc->start, resource_size(rc));
 	if (lnw->reg_base == NULL) {
 		retval = -EINVAL;
 		goto err_kmalloc;
 	}
 	spin_lock_init(&lnw->lock);
 	gc = &lnw->chip;
 	gc->label = dev_name(&pdev->dev);
 	gc->owner = THIS_MODULE;
 	gc->direction_input = lnw_gpio_direction_input;
 	gc->direction_output = lnw_gpio_direction_output;
 	gc->get = lnw_gpio_get;
 	gc->set = lnw_gpio_set;
 	gc->to_irq = NULL;
 	gc->base = 0;
 	gc->ngpio = 64;
 	gc->can_sleep = 0;
 	retval = gpiochip_add(gc);
 	if (retval) {
 		dev_err(&pdev->dev, "whitneypoint gpiochip_add error %d\n",
 								retval);
 		goto err_ioremap;
 	}
 	platform_set_drvdata(pdev, lnw);
 	return 0;
 err_ioremap:
 	iounmap(lnw->reg_base);
 err_kmalloc:
 	kfree(lnw);
 	return retval;
 }

 static int __devexit wp_gpio_remove(struct platform_device *pdev)
 {
 	struct lnw_gpio *lnw = platform_get_drvdata(pdev);
 	int err;
 	err = gpiochip_remove(&lnw->chip);
 	if (err)
 		dev_err(&pdev->dev, "failed to remove gpio_chip.\n");
 	iounmap(lnw->reg_base);
 	kfree(lnw);
 	platform_set_drvdata(pdev, NULL);
 	return 0;
 }

 static struct platform_driver wp_gpio_driver = {
 	.probe		= wp_gpio_probe,
 	.remove		= wp_gpio_remove,
 	.driver		= {
 		.name	= "wp_gpio",
 		.owner	= THIS_MODULE,
 	},
 };

 static int __init lnw_gpio_init(void)
 {
 	int ret;
 	ret =  pci_register_driver(&lnw_gpio_driver);
 	if (ret < 0)
 		return ret;
 	ret = platform_driver_register(&wp_gpio_driver);
 	if (ret < 0)
 		pci_unregister_driver(&lnw_gpio_driver);
 	return ret;
 }

 device_initcall(lnw_gpio_init);
	/*
	* Moorestown platform Langwell chip GPIO driver
	*
	* Copyright (c) 2008 - 2009, Intel Corporation.
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	*/

	/* Supports:
	* Moorestown platform Langwell chip.
	* Medfield platform Penwell chip.
	* Whitney point.
	*/

	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/platform_device.h>
	#include <linux/kernel.h>
	#include <linux/delay.h>
	#include <linux/stddef.h>
	#include <linux/interrupt.h>
	#include <linux/init.h>
	#include <linux/irq.h>
	#include <linux/io.h>
	#include <linux/gpio.h>
	#include <linux/slab.h>
	#include <linux/pm_runtime.h>
	#include <linux/irqdomain.h>

	/*
	* Langwell chip has 64 pins and thus there are 2 32bit registers to control
	* each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
	* registers to control them, so we only define the order here instead of a
	* structure, to get a bit offset for a pin (use GPDR as an example):
	*
	* nreg = ngpio / 32;
	* reg = offset / 32;
	* bit = offset % 32;
	* reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
	*
	* so the bit of reg_addr is to control pin offset's GPDR feature
	*/

	enum GPIO_REG {
	GPLR = 0, /* pin level read-only */
	GPDR, /* pin direction */
	GPSR, /* pin set */
	GPCR, /* pin clear */
	GRER, /* rising edge detect */
	GFER, /* falling edge detect */
	GEDR, /* edge detect result */
	GAFR, /* alt function */
	};

	struct lnw_gpio {
	struct gpio_chip chip;
	void *reg_base;
	spinlock_t lock;
	struct pci_dev *pdev;
	struct irq_domain *domain;
	};

	static void __iomem gpio_reg(struct gpio_chip chip, unsigned offset,
	enum GPIO_REG reg_type)
	{
	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
	unsigned nreg = chip->ngpio / 32;
	u8 reg = offset / 32;
	void __iomem *ptr;

	ptr = (void __iomem )(lnw->reg_base + reg_type nreg * 4 + reg * 4);
	return ptr;
	}

	static void __iomem gpio_reg_2bit(struct gpio_chip chip, unsigned offset,
	enum GPIO_REG reg_type)
	{
	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
	unsigned nreg = chip->ngpio / 32;
	u8 reg = offset / 16;
	void __iomem *ptr;

	ptr = (void __iomem )(lnw->reg_base + reg_type nreg * 4 + reg * 4);
	return ptr;
	}

	static int lnw_gpio_request(struct gpio_chip *chip, unsigned offset)
	{
	void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
	u32 value = readl(gafr);
	int shift = (offset % 16) << 1, af = (value >> shift) & 3;

	if (af) {
	value &= ~(3 << shift);
	writel(value, gafr);
	}
	return 0;
	}

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

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

	static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
	{
	void __iomem gpsr, gpcr;

	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);
	}
	}

	static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
	{
	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
	u32 value;
	unsigned long flags;

	if (lnw->pdev)
	pm_runtime_get(&lnw->pdev->dev);

	spin_lock_irqsave(&lnw->lock, flags);
	value = readl(gpdr);
	value &= ~BIT(offset % 32);
	writel(value, gpdr);
	spin_unlock_irqrestore(&lnw->lock, flags);

	if (lnw->pdev)
	pm_runtime_put(&lnw->pdev->dev);

	return 0;
	}

	static int lnw_gpio_direction_output(struct gpio_chip *chip,
	unsigned offset, int value)
	{
	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
	unsigned long flags;

	lnw_gpio_set(chip, offset, value);

	if (lnw->pdev)
	pm_runtime_get(&lnw->pdev->dev);

	spin_lock_irqsave(&lnw->lock, flags);
	value = readl(gpdr);
	value \|= BIT(offset % 32);
	writel(value, gpdr);
	spin_unlock_irqrestore(&lnw->lock, flags);

	if (lnw->pdev)
	pm_runtime_put(&lnw->pdev->dev);

	return 0;
	}

	static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
	{
	struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
	return irq_create_mapping(lnw->domain, offset);
	}

	static int lnw_irq_type(struct irq_data *d, unsigned type)
	{
	struct lnw_gpio *lnw = irq_data_get_irq_chip_data(d);
	u32 gpio = irqd_to_hwirq(d);
	unsigned long flags;
	u32 value;
	void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
	void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);

	if (gpio >= lnw->chip.ngpio)
	return -EINVAL;

	if (lnw->pdev)
	pm_runtime_get(&lnw->pdev->dev);

	spin_lock_irqsave(&lnw->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);
	spin_unlock_irqrestore(&lnw->lock, flags);

	if (lnw->pdev)
	pm_runtime_put(&lnw->pdev->dev);

	return 0;
	}

	static void lnw_irq_unmask(struct irq_data *d)
	{
	}

	static void lnw_irq_mask(struct irq_data *d)
	{
	}

	static struct irq_chip lnw_irqchip = {
	.name = "LNW-GPIO",
	.irq_mask = lnw_irq_mask,
	.irq_unmask = lnw_irq_unmask,
	.irq_set_type = lnw_irq_type,
	};

	static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = { /* pin number */
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
	{ 0, }
	};
	MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);

	static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
	{
	struct irq_data *data = irq_desc_get_irq_data(desc);
	struct lnw_gpio *lnw = irq_data_get_irq_handler_data(data);
	struct irq_chip *chip = irq_data_get_irq_chip(data);
	u32 base, gpio, mask;
	unsigned long pending;
	void __iomem *gedr;

	/* check GPIO controller to check which pin triggered the interrupt */
	for (base = 0; base < lnw->chip.ngpio; base += 32) {
	gedr = gpio_reg(&lnw->chip, base, GEDR);
	while ((pending = readl(gedr))) {
	gpio = __ffs(pending);
	mask = BIT(gpio);
	/* Clear before handling so we can't lose an edge */
	writel(mask, gedr);
	generic_handle_irq(irq_find_mapping(lnw->domain,
	base + gpio));
	}
	}

	chip->irq_eoi(data);
	}

	static void lnw_irq_init_hw(struct lnw_gpio *lnw)
	{
	void __iomem *reg;
	unsigned base;

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

	static int lnw_gpio_irq_map(struct irq_domain *d, unsigned int virq,
	irq_hw_number_t hw)
	{
	struct lnw_gpio *lnw = d->host_data;

	irq_set_chip_and_handler_name(virq, &lnw_irqchip, handle_simple_irq,
	"demux");
	irq_set_chip_data(virq, lnw);
	irq_set_irq_type(virq, IRQ_TYPE_NONE);

	return 0;
	}

	static const struct irq_domain_ops lnw_gpio_irq_ops = {
	.map = lnw_gpio_irq_map,
	.xlate = irq_domain_xlate_twocell,
	};

	#ifdef CONFIG_PM
	static int lnw_gpio_runtime_resume(struct device *dev)
	{
	return 0;
	}

	static int lnw_gpio_runtime_suspend(struct device *dev)
	{
	return 0;
	}

	static int lnw_gpio_runtime_idle(struct device *dev)
	{
	int err = pm_schedule_suspend(dev, 500);

	if (!err)
	return 0;

	return -EBUSY;
	}

	#else
	#define lnw_gpio_runtime_suspend NULL
	#define lnw_gpio_runtime_resume NULL
	#define lnw_gpio_runtime_idle NULL
	#endif

	static const struct dev_pm_ops lnw_gpio_pm_ops = {
	.runtime_suspend = lnw_gpio_runtime_suspend,
	.runtime_resume = lnw_gpio_runtime_resume,
	.runtime_idle = lnw_gpio_runtime_idle,
	};

	static int lnw_gpio_probe(struct pci_dev *pdev,
	const struct pci_device_id *id)
	{
	void *base;
	resource_size_t start, len;
	struct lnw_gpio *lnw;
	u32 gpio_base;
	int retval;
	int ngpio = id->driver_data;

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

	retval = pci_request_regions(pdev, "langwell_gpio");
	if (retval) {
	dev_err(&pdev->dev, "error requesting resources\n");
	goto err2;
	}
	/* get the gpio_base from bar1 */
	start = pci_resource_start(pdev, 1);
	len = pci_resource_len(pdev, 1);
	base = ioremap_nocache(start, len);
	if (!base) {
	dev_err(&pdev->dev, "error mapping bar1\n");
	retval = -EFAULT;
	goto err3;
	}
	gpio_base = ((u32 )base + 1);
	/* release the IO mapping, since we already get the info from bar1 */
	iounmap(base);
	/* get the register base from bar0 */
	start = pci_resource_start(pdev, 0);
	len = pci_resource_len(pdev, 0);
	base = devm_ioremap_nocache(&pdev->dev, start, len);
	if (!base) {
	dev_err(&pdev->dev, "error mapping bar0\n");
	retval = -EFAULT;
	goto err3;
	}

	lnw = devm_kzalloc(&pdev->dev, sizeof(struct lnw_gpio), GFP_KERNEL);
	if (!lnw) {
	dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
	retval = -ENOMEM;
	goto err3;
	}

	lnw->domain = irq_domain_add_linear(pdev->dev.of_node, ngpio,
	&lnw_gpio_irq_ops, lnw);
	if (!lnw->domain) {
	retval = -ENOMEM;
	goto err3;
	}

	lnw->reg_base = base;
	lnw->chip.label = dev_name(&pdev->dev);
	lnw->chip.request = lnw_gpio_request;
	lnw->chip.direction_input = lnw_gpio_direction_input;
	lnw->chip.direction_output = lnw_gpio_direction_output;
	lnw->chip.get = lnw_gpio_get;
	lnw->chip.set = lnw_gpio_set;
	lnw->chip.to_irq = lnw_gpio_to_irq;
	lnw->chip.base = gpio_base;
	lnw->chip.ngpio = ngpio;
	lnw->chip.can_sleep = 0;
	lnw->pdev = pdev;
	pci_set_drvdata(pdev, lnw);
	retval = gpiochip_add(&lnw->chip);
	if (retval) {
	dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
	goto err3;
	}

	lnw_irq_init_hw(lnw);

	irq_set_handler_data(pdev->irq, lnw);
	irq_set_chained_handler(pdev->irq, lnw_irq_handler);

	spin_lock_init(&lnw->lock);

	pm_runtime_put_noidle(&pdev->dev);
	pm_runtime_allow(&pdev->dev);

	return 0;

	err3:
	pci_release_regions(pdev);
	err2:
	pci_disable_device(pdev);
	return retval;
	}

	static struct pci_driver lnw_gpio_driver = {
	.name = "langwell_gpio",
	.id_table = lnw_gpio_ids,
	.probe = lnw_gpio_probe,
	.driver = {
	.pm = &lnw_gpio_pm_ops,
	},
	};


	static int wp_gpio_probe(struct platform_device *pdev)
	{
	struct lnw_gpio *lnw;
	struct gpio_chip *gc;
	struct resource *rc;
	int retval = 0;

	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!rc)
	return -EINVAL;

	lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
	if (!lnw) {
	dev_err(&pdev->dev,
	"can't allocate whitneypoint_gpio chip data\n");
	return -ENOMEM;
	}
	lnw->reg_base = ioremap_nocache(rc->start, resource_size(rc));
	if (lnw->reg_base == NULL) {
	retval = -EINVAL;
	goto err_kmalloc;
	}
	spin_lock_init(&lnw->lock);
	gc = &lnw->chip;
	gc->label = dev_name(&pdev->dev);
	gc->owner = THIS_MODULE;
	gc->direction_input = lnw_gpio_direction_input;
	gc->direction_output = lnw_gpio_direction_output;
	gc->get = lnw_gpio_get;
	gc->set = lnw_gpio_set;
	gc->to_irq = NULL;
	gc->base = 0;
	gc->ngpio = 64;
	gc->can_sleep = 0;
	retval = gpiochip_add(gc);
	if (retval) {
	dev_err(&pdev->dev, "whitneypoint gpiochip_add error %d\n",
	retval);
	goto err_ioremap;
	}
	platform_set_drvdata(pdev, lnw);
	return 0;
	err_ioremap:
	iounmap(lnw->reg_base);
	err_kmalloc:
	kfree(lnw);
	return retval;
	}

	static int __devexit wp_gpio_remove(struct platform_device *pdev)
	{
	struct lnw_gpio *lnw = platform_get_drvdata(pdev);
	int err;
	err = gpiochip_remove(&lnw->chip);
	if (err)
	dev_err(&pdev->dev, "failed to remove gpio_chip.\n");
	iounmap(lnw->reg_base);
	kfree(lnw);
	platform_set_drvdata(pdev, NULL);
	return 0;
	}

	static struct platform_driver wp_gpio_driver = {
	.probe = wp_gpio_probe,
	.remove = wp_gpio_remove,
	.driver = {
	.name = "wp_gpio",
	.owner = THIS_MODULE,
	},
	};

	static int __init lnw_gpio_init(void)
	{
	int ret;
	ret = pci_register_driver(&lnw_gpio_driver);
	if (ret < 0)
	return ret;
	ret = platform_driver_register(&wp_gpio_driver);
	if (ret < 0)
	pci_unregister_driver(&lnw_gpio_driver);
	return ret;
	}

	device_initcall(lnw_gpio_init);