Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux

Pull GPIO changes from Grant Likely:
 "The usual selection of bug fixes and driver updates for GPIO.  Nothing
  really stands out except the addition of the GRGPIO driver and some
  enhacements to ACPI support"

I'm pulling this despite the earlier mess.  Let's hope it compiles these
days.

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (46 commits)
  gpio: grgpio: Add irq support
  gpio: grgpio: Add device driver for GRGPIO cores
  gpiolib-acpi: introduce acpi_get_gpio_by_index() helper
  GPIO: gpio-generic: remove kfree() from bgpio_remove call
  gpio / ACPI: Handle ACPI events in accordance with the spec
  gpio: lpc32xx: Fix off-by-one valid range checking for bank
  gpio: mcp23s08: convert driver to DT
  gpio/omap: force restore if context loss is not detectable
  gpio/omap: optimise interrupt service routine
  gpio/omap: remove extra context restores in *_runtime_resume()
  gpio/omap: free irq domain in probe() failure paths
  gpio: gpio-generic: Add 16 and 32 bit big endian byte order support
  gpio: samsung: Add terminating entry for exynos_pinctrl_ids
  gpio: mvebu: add dbg_show function
  MAX7301 GPIO: Do not force SPI speed when using OF Platform
  gpio: gpio-tps65910.c: fix checkpatch error
  gpio: gpio-timberdale.c: fix checkpatch error
  gpio: gpio-tc3589x.c: fix checkpatch errors
  gpio: gpio-stp-xway.c: fix checkpatch error
  gpio: gpio-sch.c: fix checkpatch error
  ...

30 files changed, 1164 insertions, 290 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b166e30b3bc..ff7f0c87745 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -297,12 +297,21 @@ config GPIO_GE_FPGA
 
 config GPIO_LYNXPOINT
 	bool "Intel Lynxpoint GPIO support"
-	depends on ACPI
+	depends on ACPI && X86
 	select IRQ_DOMAIN
 	help
 	  driver for GPIO functionality on Intel Lynxpoint PCH chipset
 	  Requires ACPI device enumeration code to set up a platform device.
 
+config GPIO_GRGPIO
+	tristate "Aeroflex Gaisler GRGPIO support"
+	depends on OF
+	select GPIO_GENERIC
+	select IRQ_DOMAIN
+	help
+	  Select this to support Aeroflex Gaisler GRGPIO cores from the GRLIB
+	  VHDL IP core library.
+
 comment "I2C GPIO expanders:"
 
 config GPIO_ARIZONA
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index a274d7df3c8..6aab73d577d 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_ARCH_DAVINCI)	+= gpio-davinci.o
 obj-$(CONFIG_GPIO_EM)		+= gpio-em.o
 obj-$(CONFIG_GPIO_EP93XX)	+= gpio-ep93xx.o
 obj-$(CONFIG_GPIO_GE_FPGA)	+= gpio-ge.o
+obj-$(CONFIG_GPIO_GRGPIO)	+= gpio-grgpio.o
 obj-$(CONFIG_GPIO_ICH)		+= gpio-ich.o
 obj-$(CONFIG_GPIO_IT8761E)	+= gpio-it8761e.o
 obj-$(CONFIG_GPIO_JANZ_TTL)	+= gpio-janz-ttl.o
diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c
index 464be961f60..721607904d0 100644
--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -137,7 +137,7 @@ static int gen_74x164_probe(struct spi_device *spi)
 
 	mutex_init(&chip->lock);
 
-	dev_set_drvdata(&spi->dev, chip);
+	spi_set_drvdata(spi, chip);
 
 	chip->spi = spi;
 
@@ -176,7 +176,7 @@ static int gen_74x164_probe(struct spi_device *spi)
 	return ret;
 
 exit_destroy:
-	dev_set_drvdata(&spi->dev, NULL);
+	spi_set_drvdata(spi, NULL);
 	mutex_destroy(&chip->lock);
 	return ret;
 }
@@ -186,11 +186,11 @@ static int gen_74x164_remove(struct spi_device *spi)
 	struct gen_74x164_chip *chip;
 	int ret;
 
-	chip = dev_get_drvdata(&spi->dev);
+	chip = spi_get_drvdata(spi);
 	if (chip == NULL)
 		return -ENODEV;
 
-	dev_set_drvdata(&spi->dev, NULL);
+	spi_set_drvdata(spi, NULL);
 
 	ret = gpiochip_remove(&chip->gpio_chip);
 	if (!ret)
diff --git a/drivers/gpio/gpio-adp5520.c b/drivers/gpio/gpio-adp5520.c
index 8afa95f831b..f33f78dcada 100644
--- a/drivers/gpio/gpio-adp5520.c
+++ b/drivers/gpio/gpio-adp5520.c
@@ -105,7 +105,7 @@ static int adp5520_gpio_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 	if (dev == NULL) {
 		dev_err(&pdev->dev, "failed to alloc memory\n");
 		return -ENOMEM;
@@ -163,7 +163,6 @@ static int adp5520_gpio_probe(struct platform_device *pdev)
 	return 0;
 
 err:
-	kfree(dev);
 	return ret;
 }
 
@@ -180,7 +179,6 @@ static int adp5520_gpio_remove(struct platform_device *pdev)
 		return ret;
 	}
 
-	kfree(dev);
 	return 0;
 }
 
diff --git a/drivers/gpio/gpio-em.c b/drivers/gpio/gpio-em.c
index deca78f9931..5cba855638b 100644
--- a/drivers/gpio/gpio-em.c
+++ b/drivers/gpio/gpio-em.c
@@ -231,10 +231,12 @@ static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int virq,
 
 static struct irq_domain_ops em_gio_irq_domain_ops = {
 	.map	= em_gio_irq_domain_map,
+	.xlate	= irq_domain_xlate_twocell,
 };
 
 static int em_gio_probe(struct platform_device *pdev)
 {
+	struct gpio_em_config pdata_dt;
 	struct gpio_em_config *pdata = pdev->dev.platform_data;
 	struct em_gio_priv *p;
 	struct resource *io[2], *irq[2];
@@ -243,7 +245,7 @@ static int em_gio_probe(struct platform_device *pdev)
 	const char *name = dev_name(&pdev->dev);
 	int ret;
 
-	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
 	if (!p) {
 		dev_err(&pdev->dev, "failed to allocate driver data\n");
 		ret = -ENOMEM;
@@ -259,24 +261,45 @@ static int em_gio_probe(struct platform_device *pdev)
 	irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
 
-	if (!io[0] || !io[1] || !irq[0] || !irq[1] || !pdata) {
-		dev_err(&pdev->dev, "missing IRQ, IOMEM or configuration\n");
+	if (!io[0] || !io[1] || !irq[0] || !irq[1]) {
+		dev_err(&pdev->dev, "missing IRQ or IOMEM\n");
 		ret = -EINVAL;
-		goto err1;
+		goto err0;
 	}
 
-	p->base0 = ioremap_nocache(io[0]->start, resource_size(io[0]));
+	p->base0 = devm_ioremap_nocache(&pdev->dev, io[0]->start,
+					resource_size(io[0]));
 	if (!p->base0) {
 		dev_err(&pdev->dev, "failed to remap low I/O memory\n");
 		ret = -ENXIO;
-		goto err1;
+		goto err0;
 	}
 
-	p->base1 = ioremap_nocache(io[1]->start, resource_size(io[1]));
+	p->base1 = devm_ioremap_nocache(&pdev->dev, io[1]->start,
+				   resource_size(io[1]));
 	if (!p->base1) {
 		dev_err(&pdev->dev, "failed to remap high I/O memory\n");
 		ret = -ENXIO;
-		goto err2;
+		goto err0;
+	}
+
+	if (!pdata) {
+		memset(&pdata_dt, 0, sizeof(pdata_dt));
+		pdata = &pdata_dt;
+
+		if (of_property_read_u32(pdev->dev.of_node, "ngpios",
+					 &pdata->number_of_pins)) {
+			dev_err(&pdev->dev, "Missing ngpios OF property\n");
+			ret = -EINVAL;
+			goto err0;
+		}
+
+		ret = of_alias_get_id(pdev->dev.of_node, "gpio");
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Couldn't get OF id\n");
+			goto err0;
+		}
+		pdata->gpio_base = ret * 32; /* 32 GPIOs per instance */
 	}
 
 	gpio_chip = &p->gpio_chip;
@@ -306,40 +329,32 @@ static int em_gio_probe(struct platform_device *pdev)
 	if (!p->irq_domain) {
 		ret = -ENXIO;
 		dev_err(&pdev->dev, "cannot initialize irq domain\n");
-		goto err3;
+		goto err0;
 	}
 
-	if (request_irq(irq[0]->start, em_gio_irq_handler, 0, name, p)) {
+	if (devm_request_irq(&pdev->dev, irq[0]->start,
+			     em_gio_irq_handler, 0, name, p)) {
 		dev_err(&pdev->dev, "failed to request low IRQ\n");
 		ret = -ENOENT;
-		goto err4;
+		goto err1;
 	}
 
-	if (request_irq(irq[1]->start, em_gio_irq_handler, 0, name, p)) {
+	if (devm_request_irq(&pdev->dev, irq[1]->start,
+			     em_gio_irq_handler, 0, name, p)) {
 		dev_err(&pdev->dev, "failed to request high IRQ\n");
 		ret = -ENOENT;
-		goto err5;
+		goto err1;
 	}
 
 	ret = gpiochip_add(gpio_chip);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to add GPIO controller\n");
-		goto err6;
+		goto err1;
 	}
 	return 0;
 
-err6:
-	free_irq(irq[1]->start, pdev);
-err5:
-	free_irq(irq[0]->start, pdev);
-err4:
-	irq_domain_remove(p->irq_domain);
-err3:
-	iounmap(p->base1);
-err2:
-	iounmap(p->base0);
 err1:
-	kfree(p);
+	irq_domain_remove(p->irq_domain);
 err0:
 	return ret;
 }
@@ -347,34 +362,43 @@ err0:
 static int em_gio_remove(struct platform_device *pdev)
 {
 	struct em_gio_priv *p = platform_get_drvdata(pdev);
-	struct resource *irq[2];
 	int ret;
 
 	ret = gpiochip_remove(&p->gpio_chip);
 	if (ret)
 		return ret;
 
-	irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
-
-	free_irq(irq[1]->start, pdev);
-	free_irq(irq[0]->start, pdev);
 	irq_domain_remove(p->irq_domain);
-	iounmap(p->base1);
-	iounmap(p->base0);
-	kfree(p);
 	return 0;
 }
 
+static const struct of_device_id em_gio_dt_ids[] = {
+	{ .compatible = "renesas,em-gio", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, em_gio_dt_ids);
+
 static struct platform_driver em_gio_device_driver = {
 	.probe		= em_gio_probe,
 	.remove		= em_gio_remove,
 	.driver		= {
 		.name	= "em_gio",
+		.of_match_table = em_gio_dt_ids,
+		.owner		= THIS_MODULE,
 	}
 };
 
-module_platform_driver(em_gio_device_driver);
+static int __init em_gio_init(void)
+{
+	return platform_driver_register(&em_gio_device_driver);
+}
+postcore_initcall(em_gio_init);
+
+static void __exit em_gio_exit(void)
+{
+	platform_driver_unregister(&em_gio_device_driver);
+}
+module_exit(em_gio_exit);
 
 MODULE_AUTHOR("Magnus Damm");
 MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver");
diff --git a/drivers/gpio/gpio-generic.c b/drivers/gpio/gpio-generic.c
index 05fcc0f247c..d2196bf7384 100644
--- a/drivers/gpio/gpio-generic.c
+++ b/drivers/gpio/gpio-generic.c
@@ -104,6 +104,26 @@ static unsigned long bgpio_read64(void __iomem *reg)
 }
 #endif /* BITS_PER_LONG >= 64 */
 
+static void bgpio_write16be(void __iomem *reg, unsigned long data)
+{
+	iowrite16be(data, reg);
+}
+
+static unsigned long bgpio_read16be(void __iomem *reg)
+{
+	return ioread16be(reg);
+}
+
+static void bgpio_write32be(void __iomem *reg, unsigned long data)
+{
+	iowrite32be(data, reg);
+}
+
+static unsigned long bgpio_read32be(void __iomem *reg)
+{
+	return ioread32be(reg);
+}
+
 static unsigned long bgpio_pin2mask(struct bgpio_chip *bgc, unsigned int pin)
 {
 	return 1 << pin;
@@ -249,7 +269,8 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
 
 static int bgpio_setup_accessors(struct device *dev,
 				 struct bgpio_chip *bgc,
-				 bool be)
+				 bool bit_be,
+				 bool byte_be)
 {
 
 	switch (bgc->bits) {
@@ -258,17 +279,33 @@ static int bgpio_setup_accessors(struct device *dev,
 		bgc->write_reg	= bgpio_write8;
 		break;
 	case 16:
-		bgc->read_reg	= bgpio_read16;
-		bgc->write_reg	= bgpio_write16;
+		if (byte_be) {
+			bgc->read_reg	= bgpio_read16be;
+			bgc->write_reg	= bgpio_write16be;
+		} else {
+			bgc->read_reg	= bgpio_read16;
+			bgc->write_reg	= bgpio_write16;
+		}
 		break;
 	case 32:
-		bgc->read_reg	= bgpio_read32;
-		bgc->write_reg	= bgpio_write32;
+		if (byte_be) {
+			bgc->read_reg	= bgpio_read32be;
+			bgc->write_reg	= bgpio_write32be;
+		} else {
+			bgc->read_reg	= bgpio_read32;
+			bgc->write_reg	= bgpio_write32;
+		}
 		break;
 #if BITS_PER_LONG >= 64
 	case 64:
-		bgc->read_reg	= bgpio_read64;
-		bgc->write_reg	= bgpio_write64;
+		if (byte_be) {
+			dev_err(dev,
+				"64 bit big endian byte order unsupported\n");
+			return -EINVAL;
+		} else {
+			bgc->read_reg	= bgpio_read64;
+			bgc->write_reg	= bgpio_write64;
+		}
 		break;
 #endif /* BITS_PER_LONG >= 64 */
 	default:
@@ -276,7 +313,7 @@ static int bgpio_setup_accessors(struct device *dev,
 		return -EINVAL;
 	}
 
-	bgc->pin2mask = be ? bgpio_pin2mask_be : bgpio_pin2mask;
+	bgc->pin2mask = bit_be ? bgpio_pin2mask_be : bgpio_pin2mask;
 
 	return 0;
 }
@@ -353,11 +390,7 @@ static int bgpio_setup_direction(struct bgpio_chip *bgc,
 
 int bgpio_remove(struct bgpio_chip *bgc)
 {
-	int err = gpiochip_remove(&bgc->gc);
-
-	kfree(bgc);
-
-	return err;
+	return gpiochip_remove(&bgc->gc);
 }
 EXPORT_SYMBOL_GPL(bgpio_remove);
 
@@ -385,7 +418,8 @@ int bgpio_init(struct bgpio_chip *bgc, struct device *dev,
 	if (ret)
 		return ret;
 
-	ret = bgpio_setup_accessors(dev, bgc, flags & BGPIOF_BIG_ENDIAN);
+	ret = bgpio_setup_accessors(dev, bgc, flags & BGPIOF_BIG_ENDIAN,
+				    flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c
new file mode 100644
index 00000000000..8e08b864765
--- /dev/null
+++ b/drivers/gpio/gpio-grgpio.c
@@ -0,0 +1,505 @@
+/*
+ * Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores.
+ *
+ * 2013 (c) Aeroflex Gaisler AB
+ *
+ * This driver supports the GRGPIO GPIO core available in the GRLIB VHDL
+ * IP core library.
+ *
+ * Full documentation of the GRGPIO core can be found here:
+ * http://www.gaisler.com/products/grlib/grip.pdf
+ *
+ * See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for
+ * information on open firmware properties.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * Contributors: Andreas Larsson <andreas@gaisler.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/basic_mmio_gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+
+#define GRGPIO_MAX_NGPIO 32
+
+#define GRGPIO_DATA		0x00
+#define GRGPIO_OUTPUT		0x04
+#define GRGPIO_DIR		0x08
+#define GRGPIO_IMASK		0x0c
+#define GRGPIO_IPOL		0x10
+#define GRGPIO_IEDGE		0x14
+#define GRGPIO_BYPASS		0x18
+#define GRGPIO_IMAP_BASE	0x20
+
+/* Structure for an irq of the core - called an underlying irq */
+struct grgpio_uirq {
+	u8 refcnt; /* Reference counter to manage requesting/freeing of uirq */
+	u8 uirq; /* Underlying irq of the gpio driver */
+};
+
+/*
+ * Structure for an irq of a gpio line handed out by this driver. The index is
+ * used to map to the corresponding underlying irq.
+ */
+struct grgpio_lirq {
+	s8 index; /* Index into struct grgpio_priv's uirqs, or -1 */
+	u8 irq; /* irq for the gpio line */
+};
+
+struct grgpio_priv {
+	struct bgpio_chip bgc;
+	void __iomem *regs;
+	struct device *dev;
+
+	u32 imask; /* irq mask shadow register */
+
+	/*
+	 * The grgpio core can have multiple "underlying" irqs. The gpio lines
+	 * can be mapped to any one or none of these underlying irqs
+	 * independently of each other. This driver sets up an irq domain and
+	 * hands out separate irqs to each gpio line
+	 */
+	struct irq_domain *domain;
+
+	/*
+	 * This array contains information on each underlying irq, each
+	 * irq of the grgpio core itself.
+	 */
+	struct grgpio_uirq uirqs[GRGPIO_MAX_NGPIO];
+
+	/*
+	 * This array contains information for each gpio line on the irqs
+	 * obtains from this driver. An index value of -1 for a certain gpio
+	 * line indicates that the line has no irq. Otherwise the index connects
+	 * the irq to the underlying irq by pointing into the uirqs array.
+	 */
+	struct grgpio_lirq lirqs[GRGPIO_MAX_NGPIO];
+};
+
+static inline struct grgpio_priv *grgpio_gc_to_priv(struct gpio_chip *gc)
+{
+	struct bgpio_chip *bgc = to_bgpio_chip(gc);
+
+	return container_of(bgc, struct grgpio_priv, bgc);
+}
+
+static void grgpio_set_imask(struct grgpio_priv *priv, unsigned int offset,
+			     int val)
+{
+	struct bgpio_chip *bgc = &priv->bgc;
+	unsigned long mask = bgc->pin2mask(bgc, offset);
+	unsigned long flags;
+
+	spin_lock_irqsave(&bgc->lock, flags);
+
+	if (val)
+		priv->imask |= mask;
+	else
+		priv->imask &= ~mask;
+	bgc->write_reg(priv->regs + GRGPIO_IMASK, priv->imask);
+
+	spin_unlock_irqrestore(&bgc->lock, flags);
+}
+
+static int grgpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+	struct grgpio_priv *priv = grgpio_gc_to_priv(gc);
+
+	if (offset > gc->ngpio)
+		return -ENXIO;
+
+	if (priv->lirqs[offset].index < 0)
+		return -ENXIO;
+
+	return irq_create_mapping(priv->domain, offset);
+}
+
+/* -------------------- IRQ chip functions -------------------- */
+
+static int grgpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
+	unsigned long flags;
+	u32 mask = BIT(d->hwirq);
+	u32 ipol;
+	u32 iedge;
+	u32 pol;
+	u32 edge;
+
+	switch (type) {
+	case IRQ_TYPE_LEVEL_LOW:
+		pol = 0;
+		edge = 0;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		pol = mask;
+		edge = 0;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		pol = 0;
+		edge = mask;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		pol = mask;
+		edge = mask;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&priv->bgc.lock, flags);
+
+	ipol = priv->bgc.read_reg(priv->regs + GRGPIO_IPOL) & ~mask;
+	iedge = priv->bgc.read_reg(priv->regs + GRGPIO_IEDGE) & ~mask;
+
+	priv->bgc.write_reg(priv->regs + GRGPIO_IPOL, ipol | pol);
+	priv->bgc.write_reg(priv->regs + GRGPIO_IEDGE, iedge | edge);
+
+	spin_unlock_irqrestore(&priv->bgc.lock, flags);
+
+	return 0;
+}
+
+static void grgpio_irq_mask(struct irq_data *d)
+{
+	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
+	int offset = d->hwirq;
+
+	grgpio_set_imask(priv, offset, 0);
+}
+
+static void grgpio_irq_unmask(struct irq_data *d)
+{
+	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
+	int offset = d->hwirq;
+
+	grgpio_set_imask(priv, offset, 1);
+}
+
+static struct irq_chip grgpio_irq_chip = {
+	.name			= "grgpio",
+	.irq_mask		= grgpio_irq_mask,
+	.irq_unmask		= grgpio_irq_unmask,
+	.irq_set_type		= grgpio_irq_set_type,
+};
+
+static irqreturn_t grgpio_irq_handler(int irq, void *dev)
+{
+	struct grgpio_priv *priv = dev;
+	int ngpio = priv->bgc.gc.ngpio;
+	unsigned long flags;
+	int i;
+	int match = 0;
+
+	spin_lock_irqsave(&priv->bgc.lock, flags);
+
+	/*
+	 * For each gpio line, call its interrupt handler if it its underlying
+	 * irq matches the current irq that is handled.
+	 */
+	for (i = 0; i < ngpio; i++) {
+		struct grgpio_lirq *lirq = &priv->lirqs[i];
+
+		if (priv->imask & BIT(i) && lirq->index >= 0 &&
+		    priv->uirqs[lirq->index].uirq == irq) {
+			generic_handle_irq(lirq->irq);
+			match = 1;
+		}
+	}
+
+	spin_unlock_irqrestore(&priv->bgc.lock, flags);
+
+	if (!match)
+		dev_warn(priv->dev, "No gpio line matched irq %d\n", irq);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * This function will be called as a consequence of the call to
+ * irq_create_mapping in grgpio_to_irq
+ */
+int grgpio_irq_map(struct irq_domain *d, unsigned int irq,
+		   irq_hw_number_t hwirq)
+{
+	struct grgpio_priv *priv = d->host_data;
+	struct grgpio_lirq *lirq;
+	struct grgpio_uirq *uirq;
+	unsigned long flags;
+	int offset = hwirq;
+	int ret = 0;
+
+	if (!priv)
+		return -EINVAL;
+
+	lirq = &priv->lirqs[offset];
+	if (lirq->index < 0)
+		return -EINVAL;
+
+	dev_dbg(priv->dev, "Mapping irq %d for gpio line %d\n",
+		irq, offset);
+
+	spin_lock_irqsave(&priv->bgc.lock, flags);
+
+	/* Request underlying irq if not already requested */
+	lirq->irq = irq;
+	uirq = &priv->uirqs[lirq->index];
+	if (uirq->refcnt == 0) {
+		ret = request_irq(uirq->uirq, grgpio_irq_handler, 0,
+				  dev_name(priv->dev), priv);
+		if (ret) {
+			dev_err(priv->dev,
+				"Could not request underlying irq %d\n",
+				uirq->uirq);
+
+			spin_unlock_irqrestore(&priv->bgc.lock, flags);
+
+			return ret;
+		}
+	}
+	uirq->refcnt++;
+
+	spin_unlock_irqrestore(&priv->bgc.lock, flags);
+
+	/* Setup irq  */
+	irq_set_chip_data(irq, priv);
+	irq_set_chip_and_handler(irq, &grgpio_irq_chip,
+				 handle_simple_irq);
+	irq_clear_status_flags(irq, IRQ_NOREQUEST);
+#ifdef CONFIG_ARM
+	set_irq_flags(irq, IRQF_VALID);
+#else
+	irq_set_noprobe(irq);
+#endif
+
+	return ret;
+}
+
+void grgpio_irq_unmap(struct irq_domain *d, unsigned int irq)
+{
+	struct grgpio_priv *priv = d->host_data;
+	int index;
+	struct grgpio_lirq *lirq;
+	struct grgpio_uirq *uirq;
+	unsigned long flags;
+	int ngpio = priv->bgc.gc.ngpio;
+	int i;
+
+#ifdef CONFIG_ARM
+	set_irq_flags(irq, 0);
+#endif
+	irq_set_chip_and_handler(irq, NULL, NULL);
+	irq_set_chip_data(irq, NULL);
+
+	spin_lock_irqsave(&priv->bgc.lock, flags);
+
+	/* Free underlying irq if last user unmapped */
+	index = -1;
+	for (i = 0; i < ngpio; i++) {
+		lirq = &priv->lirqs[i];
+		if (lirq->irq == irq) {
+			grgpio_set_imask(priv, i, 0);
+			lirq->irq = 0;
+			index = lirq->index;
+			break;
+		}
+	}
+	WARN_ON(index < 0);
+
+	if (index >= 0) {
+		uirq = &priv->uirqs[lirq->index];
+		uirq->refcnt--;
+		if (uirq->refcnt == 0)
+			free_irq(uirq->uirq, priv);
+	}
+
+	spin_unlock_irqrestore(&priv->bgc.lock, flags);
+}
+
+static struct irq_domain_ops grgpio_irq_domain_ops = {
+	.map	= grgpio_irq_map,
+	.unmap	= grgpio_irq_unmap,
+};
+
+/* ------------------------------------------------------------ */
+
+static int grgpio_probe(struct platform_device *ofdev)
+{
+	struct device_node *np = ofdev->dev.of_node;
+	void  __iomem *regs;
+	struct gpio_chip *gc;
+	struct bgpio_chip *bgc;
+	struct grgpio_priv *priv;
+	struct resource *res;
+	int err;
+	u32 prop;
+	s32 *irqmap;
+	int size;
+	int i;
+
+	priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
+	regs = devm_ioremap_resource(&ofdev->dev, res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	bgc = &priv->bgc;
+	err = bgpio_init(bgc, &ofdev->dev, 4, regs + GRGPIO_DATA,
+			 regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL,
+			 BGPIOF_BIG_ENDIAN_BYTE_ORDER);
+	if (err) {
+		dev_err(&ofdev->dev, "bgpio_init() failed\n");
+		return err;
+	}
+
+	priv->regs = regs;
+	priv->imask = bgc->read_reg(regs + GRGPIO_IMASK);
+	priv->dev = &ofdev->dev;
+
+	gc = &bgc->gc;
+	gc->of_node = np;
+	gc->owner = THIS_MODULE;
+	gc->to_irq = grgpio_to_irq;
+	gc->label = np->full_name;
+	gc->base = -1;
+
+	err = of_property_read_u32(np, "nbits", &prop);
+	if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) {
+		gc->ngpio = GRGPIO_MAX_NGPIO;
+		dev_dbg(&ofdev->dev,
+			"No or invalid nbits property: assume %d\n", gc->ngpio);
+	} else {
+		gc->ngpio = prop;
+	}
+
+	/*
+	 * The irqmap contains the index values indicating which underlying irq,
+	 * if anyone, is connected to that line
+	 */
+	irqmap = (s32 *)of_get_property(np, "irqmap", &size);
+	if (irqmap) {
+		if (size < gc->ngpio) {
+			dev_err(&ofdev->dev,
+				"irqmap shorter than ngpio (%d < %d)\n",
+				size, gc->ngpio);
+			return -EINVAL;
+		}
+
+		priv->domain = irq_domain_add_linear(np, gc->ngpio,
+						     &grgpio_irq_domain_ops,
+						     priv);
+		if (!priv->domain) {
+			dev_err(&ofdev->dev, "Could not add irq domain\n");
+			return -EINVAL;
+		}
+
+		for (i = 0; i < gc->ngpio; i++) {
+			struct grgpio_lirq *lirq;
+			int ret;
+
+			lirq = &priv->lirqs[i];
+			lirq->index = irqmap[i];
+
+			if (lirq->index < 0)
+				continue;
+
+			ret = platform_get_irq(ofdev, lirq->index);
+			if (ret <= 0) {
+				/*
+				 * Continue without irq functionality for that
+				 * gpio line
+				 */
+				dev_err(priv->dev,
+					"Failed to get irq for offset %d\n", i);
+				continue;
+			}
+			priv->uirqs[lirq->index].uirq = ret;
+		}
+	}
+
+	platform_set_drvdata(ofdev, priv);
+
+	err = gpiochip_add(gc);
+	if (err) {
+		dev_err(&ofdev->dev, "Could not add gpiochip\n");
+		return err;
+	}
+
+	dev_info(&ofdev->dev, "regs=0x%p, base=%d, ngpio=%d, irqs=%s\n",
+		 priv->regs, gc->base, gc->ngpio, priv->domain ? "on" : "off");
+
+	return 0;
+}
+
+static int grgpio_remove(struct platform_device *ofdev)
+{
+	struct grgpio_priv *priv = platform_get_drvdata(ofdev);
+	unsigned long flags;
+	int i;
+	int ret = 0;
+
+	spin_lock_irqsave(&priv->bgc.lock, flags);
+
+	if (priv->domain) {
+		for (i = 0; i < GRGPIO_MAX_NGPIO; i++) {
+			if (priv->uirqs[i].refcnt != 0) {
+				ret = -EBUSY;
+				goto out;
+			}
+		}
+	}
+
+	ret = gpiochip_remove(&priv->bgc.gc);
+	if (ret)
+		goto out;
+
+	if (priv->domain)
+		irq_domain_remove(priv->domain);
+
+out:
+	spin_unlock_irqrestore(&priv->bgc.lock, flags);
+
+	return ret;
+}
+
+static struct of_device_id grgpio_match[] = {
+	{.name = "GAISLER_GPIO"},
+	{.name = "01_01a"},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, grgpio_match);
+
+static struct platform_driver grgpio_driver = {
+	.driver = {
+		.name = "grgpio",
+		.owner = THIS_MODULE,
+		.of_match_table = grgpio_match,
+	},
+	.probe = grgpio_probe,
+	.remove = grgpio_remove,
+};
+module_platform_driver(grgpio_driver);
+
+MODULE_AUTHOR("Aeroflex Gaisler AB.");
+MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO");
+MODULE_LICENSE("GPL");
diff --