gpio: bcm281xx: Add GPIO driver

Add the GPIO driver for the Broadcom bcm281xx family of mobile SoCs.
These GPIO controllers may contain up to 8 banks where each bank
includes 32 pins that can be driven high or low and act as an edge
sensitive interrupt.
Signed-off-by: Markus Mayer <markus.mayer@linaro.org>
Reviewed-by: Christian Daudt <csd@broadcom.com>
Reviewed-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
[Added depends on OF_GPIO]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/gpio/gpio-bcm-kona.txt

+Broadcom Kona Family GPIO
+=========================
+
+This GPIO driver is used in the following Broadcom SoCs:
+  BCM11130, BCM11140, BCM11351, BCM28145, BCM28155
+
+The Broadcom GPIO Controller IP can be configured prior to synthesis to
+support up to 8 banks of 32 GPIOs where each bank has its own IRQ. The
+GPIO controller only supports edge, not level, triggering of interrupts.
+
+Required properties
+-------------------
+
+- compatible: "brcm,bcm11351-gpio", "brcm,kona-gpio"
+- reg: Physical base address and length of the controller's registers.
+- interrupts: The interrupt outputs from the controller. There is one GPIO
+  interrupt per GPIO bank. The number of interrupts listed depends on the
+  number of GPIO banks on the SoC. The interrupts must be ordered by bank,
+  starting with bank 0. There is always a 1:1 mapping between banks and
+  IRQs.
+- #gpio-cells: Should be <2>. The first cell is the pin number, the second
+  cell is used to specify optional parameters:
+  - bit 0 specifies polarity (0 for normal, 1 for inverted)
+  See also "gpio-specifier" in .../devicetree/bindings/gpio/gpio.txt.
+- #interrupt-cells: Should be <2>. The first cell is the GPIO number. The
+  second cell is used to specify flags. The following subset of flags is
+  supported:
+  - trigger type (bits[1:0]):
+      1 = low-to-high edge triggered.
+      2 = high-to-low edge triggered.
+      3 = low-to-high or high-to-low edge triggered
+      Valid values are 1, 2, 3
+  See also .../devicetree/bindings/interrupt-controller/interrupts.txt.
+- gpio-controller: Marks the device node as a GPIO controller.
+- interrupt-controller: Marks the device node as an interrupt controller.
+
+Example:
+	gpio: gpio@35003000 {
+		compatible = "brcm,bcm11351-gpio", "brcm,kona-gpio";
+		reg = <0x35003000 0x800>;
+		interrupts =
+		       <GIC_SPI 106 IRQ_TYPE_LEVEL_HIGH
+			GIC_SPI 115 IRQ_TYPE_LEVEL_HIGH
+			GIC_SPI 114 IRQ_TYPE_LEVEL_HIGH
+			GIC_SPI 113 IRQ_TYPE_LEVEL_HIGH
+			GIC_SPI 112 IRQ_TYPE_LEVEL_HIGH
+			GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
+		#gpio-cells = <2>;
+		#interrupt-cells = <2>;
+		gpio-controller;
+		interrupt-controller;
+	};

drivers/gpio/Kconfig

@@ -759,6 +759,12 @@ config GPIO_MSIC
 	  Enable support for GPIO on intel MSIC controllers found in
 	  intel MID devices
 
+config GPIO_BCM_KONA
+	bool "Broadcom Kona GPIO"
+	depends on OF_GPIO
+	help
+	  Turn on GPIO support for Broadcom "Kona" chips.
+
 comment "USB GPIO expanders:"
 
 config GPIO_VIPERBOARD

drivers/gpio/Makefile

@@ -16,6 +16,7 @@ obj-$(CONFIG_GPIO_ADP5520)	+= gpio-adp5520.o
 obj-$(CONFIG_GPIO_ADP5588)	+= gpio-adp5588.o
 obj-$(CONFIG_GPIO_AMD8111)	+= gpio-amd8111.o
 obj-$(CONFIG_GPIO_ARIZONA)	+= gpio-arizona.o
+obj-$(CONFIG_GPIO_BCM_KONA)	+= gpio-bcm-kona.o
 obj-$(CONFIG_GPIO_BT8XX)	+= gpio-bt8xx.o
 obj-$(CONFIG_GPIO_CLPS711X)	+= gpio-clps711x.o
 obj-$(CONFIG_GPIO_CS5535)	+= gpio-cs5535.o

drivers/gpio/gpio-bcm-kona.c

+/*
+ * Copyright (C) 2012-2013 Broadcom Corporation
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/module.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+
+#define BCM_GPIO_PASSWD				0x00a5a501
+#define GPIO_PER_BANK				32
+#define GPIO_MAX_BANK_NUM			8
+
+#define GPIO_BANK(gpio)				((gpio) >> 5)
+#define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
+
+#define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
+#define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
+#define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
+#define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
+#define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
+#define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
+#define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
+#define GPIO_CONTROL(bank)			(0x00000100 + ((bank) << 2))
+#define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
+
+#define GPIO_GPPWR_OFFSET			0x00000520
+
+#define GPIO_GPCTR0_DBR_SHIFT			5
+#define GPIO_GPCTR0_DBR_MASK			0x000001e0
+
+#define GPIO_GPCTR0_ITR_SHIFT			3
+#define GPIO_GPCTR0_ITR_MASK			0x00000018
+#define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
+#define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
+#define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
+
+#define GPIO_GPCTR0_IOTR_MASK			0x00000001
+#define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
+#define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
+
+#define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
+
+#define LOCK_CODE				0xffffffff
+#define UNLOCK_CODE				0x00000000
+
+struct bcm_kona_gpio {
+	void __iomem *reg_base;
+	int num_bank;
+	spinlock_t lock;
+	struct gpio_chip gpio_chip;
+	struct irq_domain *irq_domain;
+	struct bcm_kona_gpio_bank *banks;
+	struct platform_device *pdev;
+};
+
+struct bcm_kona_gpio_bank {
+	int id;
+	int irq;
+	/* Used in the interrupt handler */
+	struct bcm_kona_gpio *kona_gpio;
+};
+
+static inline struct bcm_kona_gpio *to_kona_gpio(struct gpio_chip *chip)
+{
+	return container_of(chip, struct bcm_kona_gpio, gpio_chip);
+}
+
+static void bcm_kona_gpio_set_lockcode_bank(void __iomem *reg_base,
+					    int bank_id, int lockcode)
+{
+	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
+	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
+}
+
+static inline void bcm_kona_gpio_lock_bank(void __iomem *reg_base, int bank_id)
+{
+	bcm_kona_gpio_set_lockcode_bank(reg_base, bank_id, LOCK_CODE);
+}
+
+static inline void bcm_kona_gpio_unlock_bank(void __iomem *reg_base,
+					     int bank_id)
+{
+	bcm_kona_gpio_set_lockcode_bank(reg_base, bank_id, UNLOCK_CODE);
+}
+
+static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val, reg_offset;
+	unsigned long flags;
+
+	kona_gpio = to_kona_gpio(chip);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	/* determine the GPIO pin direction */
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= GPIO_GPCTR0_IOTR_MASK;
+
+	/* this function only applies to output pin */
+	if (GPIO_GPCTR0_IOTR_CMD_INPUT == val)
+		goto out;
+
+	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
+
+	val = readl(reg_base + reg_offset);
+	val |= BIT(bit);
+	writel(val, reg_base + reg_offset);
+
+out:
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+}
+
+static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val, reg_offset;
+	unsigned long flags;
+
+	kona_gpio = to_kona_gpio(chip);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	/* determine the GPIO pin direction */
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= GPIO_GPCTR0_IOTR_MASK;
+
+	/* read the GPIO bank status */
+	reg_offset = (GPIO_GPCTR0_IOTR_CMD_INPUT == val) ?
+	    GPIO_IN_STATUS(bank_id) : GPIO_OUT_STATUS(bank_id);
+	val = readl(reg_base + reg_offset);
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+
+	/* return the specified bit status */
+	return !!(val & bit);
+}
+
+static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	u32 val;
+	unsigned long flags;
+	int bank_id = GPIO_BANK(gpio);
+
+	kona_gpio = to_kona_gpio(chip);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= ~GPIO_GPCTR0_IOTR_MASK;
+	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
+	writel(val, reg_base + GPIO_CONTROL(gpio));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+
+	return 0;
+}
+
+static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
+					  unsigned gpio, int value)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val, reg_offset;
+	unsigned long flags;
+
+	kona_gpio = to_kona_gpio(chip);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= ~GPIO_GPCTR0_IOTR_MASK;
+	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
+	writel(val, reg_base + GPIO_CONTROL(gpio));
+	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
+
+	val = readl(reg_base + reg_offset);
+	val |= BIT(bit);
+	writel(val, reg_base + reg_offset);
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+
+	return 0;
+}
+
+static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
+{
+	struct bcm_kona_gpio *kona_gpio;
+
+	kona_gpio = to_kona_gpio(chip);
+	if (gpio >= kona_gpio->gpio_chip.ngpio)
+		return -ENXIO;
+	return irq_create_mapping(kona_gpio->irq_domain, gpio);
+}
+
+static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
+				      unsigned debounce)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	u32 val, res;
+	unsigned long flags;
+	int bank_id = GPIO_BANK(gpio);
+
+	kona_gpio = to_kona_gpio(chip);
+	reg_base = kona_gpio->reg_base;
+	/* debounce must be 1-128ms (or 0) */
+	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
+		dev_err(chip->dev, "Debounce value %u not in range\n",
+			debounce);
+		return -EINVAL;
+	}
+
+	/* calculate debounce bit value */
+	if (debounce != 0) {
+		/* Convert to ms */
+		debounce /= 1000;
+		/* find the MSB */
+		res = fls(debounce) - 1;
+		/* Check if MSB-1 is set (round up or down) */
+		if (res > 0 && (debounce & BIT(res - 1)))
+			res++;
+	}
+
+	/* spin lock for read-modify-write of the GPIO register */
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= ~GPIO_GPCTR0_DBR_MASK;
+
+	if (debounce == 0) {
+		/* disable debounce */
+		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
+	} else {
+		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
+		    (res << GPIO_GPCTR0_DBR_SHIFT);
+	}
+
+	writel(val, reg_base + GPIO_CONTROL(gpio));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+
+	return 0;
+}
+
+static struct gpio_chip template_chip = {
+	.label = "bcm-kona-gpio",
+	.direction_input = bcm_kona_gpio_direction_input,
+	.get = bcm_kona_gpio_get,
+	.direction_output = bcm_kona_gpio_direction_output,
+	.set = bcm_kona_gpio_set,
+	.set_debounce = bcm_kona_gpio_set_debounce,
+	.to_irq = bcm_kona_gpio_to_irq,
+	.base = 0,
+};
+
+static void bcm_kona_gpio_irq_ack(struct irq_data *d)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int gpio = d->hwirq;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val;
+	unsigned long flags;
+
+	kona_gpio = irq_data_get_irq_chip_data(d);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
+	val |= BIT(bit);
+	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+}
+
+static void bcm_kona_gpio_irq_mask(struct irq_data *d)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int gpio = d->hwirq;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val;
+	unsigned long flags;
+
+	kona_gpio = irq_data_get_irq_chip_data(d);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_INT_MASK(bank_id));
+	val |= BIT(bit);
+	writel(val, reg_base + GPIO_INT_MASK(bank_id));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+}
+
+static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int gpio = d->hwirq;
+	int bank_id = GPIO_BANK(gpio);
+	int bit = GPIO_BIT(gpio);
+	u32 val;
+	unsigned long flags;
+
+	kona_gpio = irq_data_get_irq_chip_data(d);
+	reg_base = kona_gpio->reg_base;
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
+	val |= BIT(bit);
+	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+}
+
+static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	struct bcm_kona_gpio *kona_gpio;
+	void __iomem *reg_base;
+	int gpio = d->hwirq;
+	u32 lvl_type;
+	u32 val;
+	unsigned long flags;
+	int bank_id = GPIO_BANK(gpio);
+
+	kona_gpio = irq_data_get_irq_chip_data(d);
+	reg_base = kona_gpio->reg_base;
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_RISING:
+		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
+		break;
+
+	case IRQ_TYPE_EDGE_FALLING:
+		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
+		break;
+
+	case IRQ_TYPE_EDGE_BOTH:
+		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
+		break;
+
+	case IRQ_TYPE_LEVEL_HIGH:
+	case IRQ_TYPE_LEVEL_LOW:
+		/* BCM GPIO doesn't support level triggering */
+	default:
+		dev_err(kona_gpio->gpio_chip.dev,
+			"Invalid BCM GPIO irq type 0x%x\n", type);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&kona_gpio->lock, flags);
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	val = readl(reg_base + GPIO_CONTROL(gpio));
+	val &= ~GPIO_GPCTR0_ITR_MASK;
+	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
+	writel(val, reg_base + GPIO_CONTROL(gpio));
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+	spin_unlock_irqrestore(&kona_gpio->lock, flags);
+
+	return 0;
+}
+
+static void bcm_kona_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	void __iomem *reg_base;
+	int bit, bank_id;
+	unsigned long sta;
+	struct bcm_kona_gpio_bank *bank = irq_get_handler_data(irq);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+
+	chained_irq_enter(chip, desc);
+
+	/*
+	 * For bank interrupts, we can't use chip_data to store the kona_gpio
+	 * pointer, since GIC needs it for its own purposes. Therefore, we get
+	 * our pointer from the bank structure.
+	 */
+	reg_base = bank->kona_gpio->reg_base;
+	bank_id = bank->id;
+	bcm_kona_gpio_unlock_bank(reg_base, bank_id);
+
+	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
+		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
+		for_each_set_bit(bit, &sta, 32) {
+			int gpio = GPIO_PER_BANK * bank_id + bit;
+			int virq = irq_find_mapping(bank->kona_gpio->irq_domain,
+						    gpio);
+			/*
+			 * Clear interrupt before handler is called so we don't
+			 * miss any interrupt occurred during executing them.
+			 */
+			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
+			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
+			/* Invoke interrupt handler */
+			generic_handle_irq(virq);
+		}
+	}
+
+	bcm_kona_gpio_lock_bank(reg_base, bank_id);
+
+	chained_irq_exit(chip, desc);
+}
+
+static struct irq_chip bcm_gpio_irq_chip = {
+	.name = "bcm-kona-gpio",
+	.irq_ack = bcm_kona_gpio_irq_ack,
+	.irq_mask = bcm_kona_gpio_irq_mask,
+	.irq_unmask = bcm_kona_gpio_irq_unmask,
+	.irq_set_type = bcm_kona_gpio_irq_set_type,
+};
+
+static struct __initconst of_device_id bcm_kona_gpio_of_match[] = {
+	{ .compatible = "brcm,kona-gpio" },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, bcm_kona_gpio_of_match);
+
+/*
+ * This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+static struct lock_class_key gpio_lock_class;
+
+static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int virq,
+				 irq_hw_number_t hwirq)
+{
+	int ret;
+
+	ret = irq_set_chip_data(virq, d->host_data);
+	if (ret < 0)
+		return ret;
+	irq_set_lockdep_class(virq, &gpio_lock_class);
+	irq_set_chip_and_handler(virq, &bcm_gpio_irq_chip, handle_simple_irq);
+	irq_set_nested_thread(virq, 1);
+	set_irq_flags(virq, IRQF_VALID);
+
+	return 0;
+}
+
+static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int virq)
+{
+	irq_set_chip_and_handler(virq, NULL, NULL);
+	irq_set_chip_data(virq, NULL);
+}
+
+static struct irq_domain_ops bcm_kona_irq_ops = {
+	.map = bcm_kona_gpio_irq_map,
+	.unmap = bcm_kona_gpio_irq_unmap,
+	.xlate = irq_domain_xlate_twocell,
+};
+
+static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
+{
+	void __iomem *reg_base;
+	int i;
+
+	reg_base = kona_gpio->reg_base;
+	/* disable interrupts and clear status */
+	for (i = 0; i < kona_gpio->num_bank; i++) {
+		bcm_kona_gpio_unlock_bank(reg_base, i);
+		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
+		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
+		bcm_kona_gpio_lock_bank(reg_base, i);
+	}
+}
+
+static int bcm_kona_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *match;
+	struct resource *res;
+	struct bcm_kona_gpio_bank *bank;
+	struct bcm_kona_gpio *kona_gpio;
+	struct gpio_chip *chip;
+	int ret;
+	int i;
+
+	match = of_match_device(bcm_kona_gpio_of_match, dev);
+	if (!match) {
+		dev_err(dev, "Failed to find gpio controller\n");
+		return -ENODEV;
+	}
+
+	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
+	if (!kona_gpio)
+		return -ENOMEM;
+
+	kona_gpio->gpio_chip = template_chip;
+	chip = &kona_gpio->gpio_chip;
+	kona_gpio->num_bank = of_irq_count(dev->of_node);
+	if (kona_gpio->num_bank == 0) {
+		dev_err(dev, "Couldn't determine # GPIO banks\n");
+		return -ENOENT;
+	}
+	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
+		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
+			GPIO_MAX_BANK_NUM);
+		return -ENXIO;
+	}
+	kona_gpio->banks = devm_kzalloc(dev,
+					kona_gpio->num_bank *
+					sizeof(*kona_gpio->banks), GFP_KERNEL);
+	if (!kona_gpio->banks)
+		return -ENOMEM;
+
+	kona_gpio->pdev = pdev;
+	platform_set_drvdata(pdev, kona_gpio);
+	chip->of_node = dev->of_node;
+	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
+
+	kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
+						      chip->ngpio,
+						      &bcm_kona_irq_ops,
+						      kona_gpio);
+	if (!kona_gpio->irq_domain) {
+		dev_err(dev, "Couldn't allocate IRQ domain\n");
+		return -ENXIO;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	kona_gpio->reg_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(kona_gpio->reg_base)) {
+		ret = -ENXIO;
+		goto err_irq_domain;
+	}
+
+	for (i = 0; i < kona_gpio->num_bank; i++) {
+		bank = &kona_gpio->banks[i];
+		bank->id = i;
+		bank->irq = platform_get_irq(pdev, i);
+		bank->kona_gpio = kona_gpio;
+		if (bank->irq < 0) {
+			dev_err(dev, "Couldn't get IRQ for bank %d", i);
+			ret = -ENOENT;
+			goto err_irq_domain;
+		}
+	}
+
+	dev_info(&pdev->dev, "Setting up Kona GPIO at 0x%p (phys %#x)\n",
+		 kona_gpio->reg_base, res->start);
+
+	bcm_kona_gpio_reset(kona_gpio);
+
+	ret = gpiochip_add(chip);
+	if (ret < 0) {
+		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
+		goto err_irq_domain;
+	}
+	for (i = 0; i < chip->ngpio; i++) {
+		int irq = bcm_kona_gpio_to_irq(chip, i);
+		irq_set_lockdep_class(irq, &gpio_lock_class);
+		irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip,
+					 handle_simple_irq);
+		set_irq_flags(irq, IRQF_VALID);
+	}
+	for (i = 0; i < kona_gpio->num_bank; i++) {
+		bank = &kona_gpio->banks[i];
+		irq_set_chained_handler(bank->irq, bcm_kona_gpio_irq_handler);
+		irq_set_handler_data(bank->irq, bank);
+	}
+
+	spin_lock_init(&kona_gpio->lock);
+
+	return 0;
+
+err_irq_domain:
+	irq_domain_remove(kona_gpio->irq_domain);
+
+	return ret;
+}
+
+static struct platform_driver bcm_kona_gpio_driver = {
+	.driver = {
+			.name = "bcm-kona-gpio",
+			.owner = THIS_MODULE,
+			.of_match_table = bcm_kona_gpio_of_match,
+	},
+	.probe = bcm_kona_gpio_probe,
+};
+
+module_platform_driver(bcm_kona_gpio_driver);
+
+MODULE_AUTHOR("Broadcom");
+MODULE_DESCRIPTION("Broadcom Kona GPIO Driver");
+MODULE_LICENSE("GPL v2");