drivers/gpio/gpio-intel-mid.c - kernel/msm-4.19 - Gitiles

 /*
  * Intel MID GPIO driver
  *
  * Copyright (c) 2008-2014,2016 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.
  */

 /* Supports:
  * Moorestown platform Langwell chip.
  * Medfield platform Penwell chip.
  * Clovertrail platform Cloverview chip.
  */

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

 #define INTEL_MID_IRQ_TYPE_EDGE		(1 << 0)
 #define INTEL_MID_IRQ_TYPE_LEVEL	(1 << 1)

 /*
  * 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 */
 };

 /* intel_mid gpio driver data */
 struct intel_mid_gpio_ddata {
 	u16 ngpio;		/* number of gpio pins */
 	u32 chip_irq_type;	/* chip interrupt type */
 };

 struct intel_mid_gpio {
 	struct gpio_chip		chip;
 	void __iomem			*reg_base;
 	spinlock_t			lock;
 	struct pci_dev			*pdev;
 };

 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
 			      enum GPIO_REG reg_type)
 {
 	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
 	unsigned nreg = chip->ngpio / 32;
 	u8 reg = offset / 32;

 	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
 }

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

 	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
 }

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

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

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

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

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

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

 	return 0;
 }

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

 	intel_gpio_set(chip, offset, value);

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

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

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

 	return 0;
 }

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

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

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

 	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);
 	spin_unlock_irqrestore(&priv->lock, flags);

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

 	return 0;
 }

 static void intel_mid_irq_unmask(struct irq_data *d)
 {
 }

 static void intel_mid_irq_mask(struct irq_data *d)
 {
 }

 static struct irq_chip intel_mid_irqchip = {
 	.name		= "INTEL_MID-GPIO",
 	.irq_mask	= intel_mid_irq_mask,
 	.irq_unmask	= intel_mid_irq_unmask,
 	.irq_set_type	= intel_mid_irq_type,
 };

 static const struct intel_mid_gpio_ddata gpio_lincroft = {
 	.ngpio = 64,
 };

 static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
 	.ngpio = 96,
 	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 };

 static const struct intel_mid_gpio_ddata gpio_penwell_core = {
 	.ngpio = 96,
 	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 };

 static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
 	.ngpio = 96,
 	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE | INTEL_MID_IRQ_TYPE_LEVEL,
 };

 static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
 	.ngpio = 96,
 	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 };

 static const struct pci_device_id intel_gpio_ids[] = {
 	{
 		/* Lincroft */
 		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
 		.driver_data = (kernel_ulong_t)&gpio_lincroft,
 	},
 	{
 		/* Penwell AON */
 		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
 		.driver_data = (kernel_ulong_t)&gpio_penwell_aon,
 	},
 	{
 		/* Penwell Core */
 		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
 		.driver_data = (kernel_ulong_t)&gpio_penwell_core,
 	},
 	{
 		/* Cloverview Aon */
 		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
 		.driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
 	},
 	{
 		/* Cloverview Core */
 		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
 		.driver_data = (kernel_ulong_t)&gpio_cloverview_core,
 	},
 	{ 0 }
 };
 MODULE_DEVICE_TABLE(pci, intel_gpio_ids);

 static void intel_mid_irq_handler(struct irq_desc *desc)
 {
 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 	struct intel_mid_gpio *priv = gpiochip_get_data(gc);
 	struct irq_data *data = irq_desc_get_irq_data(desc);
 	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 < priv->chip.ngpio; base += 32) {
 		gedr = gpio_reg(&priv->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(gc->irq.domain,
 							    base + gpio));
 		}
 	}

 	chip->irq_eoi(data);
 }

 static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
 {
 	void __iomem *reg;
 	unsigned 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);
 		/* Clear the edge detect status register */
 		reg = gpio_reg(&priv->chip, base, GEDR);
 		writel(~0, reg);
 	}
 }

 static int __maybe_unused intel_gpio_runtime_idle(struct device *dev)
 {
 	int err = pm_schedule_suspend(dev, 500);
 	return err ?: -EBUSY;
 }

 static const struct dev_pm_ops intel_gpio_pm_ops = {
 	SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
 };

 static int intel_gpio_probe(struct pci_dev *pdev,
 			  const struct pci_device_id *id)
 {
 	void __iomem *base;
 	struct intel_mid_gpio *priv;
 	u32 gpio_base;
 	u32 irq_base;
 	int retval;
 	struct intel_mid_gpio_ddata *ddata =
 				(struct intel_mid_gpio_ddata *)id->driver_data;

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

 	retval = pcim_iomap_regions(pdev, 1 << 0 | 1 << 1, 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);
 	gpio_base = readl(sizeof(u32) + base);

 	/* release the IO mapping, since we already get the info from bar1 */
 	pcim_iounmap_regions(pdev, 1 << 1);

 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv) {
 		dev_err(&pdev->dev, "can't allocate chip data\n");
 		return -ENOMEM;
 	}

 	priv->reg_base = pcim_iomap_table(pdev)[0];
 	priv->chip.label = dev_name(&pdev->dev);
 	priv->chip.parent = &pdev->dev;
 	priv->chip.request = intel_gpio_request;
 	priv->chip.direction_input = intel_gpio_direction_input;
 	priv->chip.direction_output = intel_gpio_direction_output;
 	priv->chip.get = intel_gpio_get;
 	priv->chip.set = intel_gpio_set;
 	priv->chip.base = gpio_base;
 	priv->chip.ngpio = ddata->ngpio;
 	priv->chip.can_sleep = false;
 	priv->pdev = pdev;

 	spin_lock_init(&priv->lock);

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

 	retval = gpiochip_irqchip_add(&priv->chip,
 				      &intel_mid_irqchip,
 				      irq_base,
 				      handle_simple_irq,
 				      IRQ_TYPE_NONE);
 	if (retval) {
 		dev_err(&pdev->dev,
 			"could not connect irqchip to gpiochip\n");
 		return retval;
 	}

 	intel_mid_irq_init_hw(priv);

 	gpiochip_set_chained_irqchip(&priv->chip,
 				     &intel_mid_irqchip,
 				     pdev->irq,
 				     intel_mid_irq_handler);

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

 	return 0;
 }

 static struct pci_driver intel_gpio_driver = {
 	.name		= "intel_mid_gpio",
 	.id_table	= intel_gpio_ids,
 	.probe		= intel_gpio_probe,
 	.driver		= {
 		.pm	= &intel_gpio_pm_ops,
 	},
 };

 builtin_pci_driver(intel_gpio_driver);
	/*
	* Intel MID GPIO driver
	*
	* Copyright (c) 2008-2014,2016 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.
	*/

	/* Supports:
	* Moorestown platform Langwell chip.
	* Medfield platform Penwell chip.
	* Clovertrail platform Cloverview chip.
	*/

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

	#define INTEL_MID_IRQ_TYPE_EDGE (1 << 0)
	#define INTEL_MID_IRQ_TYPE_LEVEL (1 << 1)

	/*
	* 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 */
	};

	/* intel_mid gpio driver data */
	struct intel_mid_gpio_ddata {
	u16 ngpio; /* number of gpio pins */
	u32 chip_irq_type; /* chip interrupt type */
	};

	struct intel_mid_gpio {
	struct gpio_chip chip;
	void __iomem *reg_base;
	spinlock_t lock;
	struct pci_dev *pdev;
	};

	static void __iomem gpio_reg(struct gpio_chip chip, unsigned offset,
	enum GPIO_REG reg_type)
	{
	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
	unsigned nreg = chip->ngpio / 32;
	u8 reg = offset / 32;

	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
	}

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

	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
	}

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

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

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

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

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

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

	return 0;
	}

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

	intel_gpio_set(chip, offset, value);

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

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

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

	return 0;
	}

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

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

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

	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);
	spin_unlock_irqrestore(&priv->lock, flags);

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

	return 0;
	}

	static void intel_mid_irq_unmask(struct irq_data *d)
	{
	}

	static void intel_mid_irq_mask(struct irq_data *d)
	{
	}

	static struct irq_chip intel_mid_irqchip = {
	.name = "INTEL_MID-GPIO",
	.irq_mask = intel_mid_irq_mask,
	.irq_unmask = intel_mid_irq_unmask,
	.irq_set_type = intel_mid_irq_type,
	};

	static const struct intel_mid_gpio_ddata gpio_lincroft = {
	.ngpio = 64,
	};

	static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
	.ngpio = 96,
	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
	};

	static const struct intel_mid_gpio_ddata gpio_penwell_core = {
	.ngpio = 96,
	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
	};

	static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
	.ngpio = 96,
	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE \| INTEL_MID_IRQ_TYPE_LEVEL,
	};

	static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
	.ngpio = 96,
	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
	};

	static const struct pci_device_id intel_gpio_ids[] = {
	{
	/* Lincroft */
	PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
	.driver_data = (kernel_ulong_t)&gpio_lincroft,
	},
	{
	/* Penwell AON */
	PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
	.driver_data = (kernel_ulong_t)&gpio_penwell_aon,
	},
	{
	/* Penwell Core */
	PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
	.driver_data = (kernel_ulong_t)&gpio_penwell_core,
	},
	{
	/* Cloverview Aon */
	PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
	.driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
	},
	{
	/* Cloverview Core */
	PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
	.driver_data = (kernel_ulong_t)&gpio_cloverview_core,
	},
	{ 0 }
	};
	MODULE_DEVICE_TABLE(pci, intel_gpio_ids);

	static void intel_mid_irq_handler(struct irq_desc *desc)
	{
	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
	struct intel_mid_gpio *priv = gpiochip_get_data(gc);
	struct irq_data *data = irq_desc_get_irq_data(desc);
	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 < priv->chip.ngpio; base += 32) {
	gedr = gpio_reg(&priv->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(gc->irq.domain,
	base + gpio));
	}
	}

	chip->irq_eoi(data);
	}

	static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
	{
	void __iomem *reg;
	unsigned 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);
	/* Clear the edge detect status register */
	reg = gpio_reg(&priv->chip, base, GEDR);
	writel(~0, reg);
	}
	}

	static int __maybe_unused intel_gpio_runtime_idle(struct device *dev)
	{
	int err = pm_schedule_suspend(dev, 500);
	return err ?: -EBUSY;
	}

	static const struct dev_pm_ops intel_gpio_pm_ops = {
	SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
	};

	static int intel_gpio_probe(struct pci_dev *pdev,
	const struct pci_device_id *id)
	{
	void __iomem *base;
	struct intel_mid_gpio *priv;
	u32 gpio_base;
	u32 irq_base;
	int retval;
	struct intel_mid_gpio_ddata *ddata =
	(struct intel_mid_gpio_ddata *)id->driver_data;

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

	retval = pcim_iomap_regions(pdev, 1 << 0 \| 1 << 1, 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);
	gpio_base = readl(sizeof(u32) + base);

	/* release the IO mapping, since we already get the info from bar1 */
	pcim_iounmap_regions(pdev, 1 << 1);

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv) {
	dev_err(&pdev->dev, "can't allocate chip data\n");
	return -ENOMEM;
	}

	priv->reg_base = pcim_iomap_table(pdev)[0];
	priv->chip.label = dev_name(&pdev->dev);
	priv->chip.parent = &pdev->dev;
	priv->chip.request = intel_gpio_request;
	priv->chip.direction_input = intel_gpio_direction_input;
	priv->chip.direction_output = intel_gpio_direction_output;
	priv->chip.get = intel_gpio_get;
	priv->chip.set = intel_gpio_set;
	priv->chip.base = gpio_base;
	priv->chip.ngpio = ddata->ngpio;
	priv->chip.can_sleep = false;
	priv->pdev = pdev;

	spin_lock_init(&priv->lock);

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

	retval = gpiochip_irqchip_add(&priv->chip,
	&intel_mid_irqchip,
	irq_base,
	handle_simple_irq,
	IRQ_TYPE_NONE);
	if (retval) {
	dev_err(&pdev->dev,
	"could not connect irqchip to gpiochip\n");
	return retval;
	}

	intel_mid_irq_init_hw(priv);

	gpiochip_set_chained_irqchip(&priv->chip,
	&intel_mid_irqchip,
	pdev->irq,
	intel_mid_irq_handler);

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

	return 0;
	}

	static struct pci_driver intel_gpio_driver = {
	.name = "intel_mid_gpio",
	.id_table = intel_gpio_ids,
	.probe = intel_gpio_probe,
	.driver = {
	.pm = &intel_gpio_pm_ops,
	},
	};

	builtin_pci_driver(intel_gpio_driver);