Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 741 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
new file mode 100644
index 0000000000..a16945e831
--- /dev/null
+++ b/drivers/gpio/gpio-xilinx.c
@@ -0,0 +1,741 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Xilinx gpio driver for xps/axi_gpio IP.
+ *
+ * Copyright 2008 - 2013 Xilinx, Inc.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+/* Register Offset Definitions */
+#define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
+#define XGPIO_TRI_OFFSET    (0x4)	/* I/O direction register  */
+
+#define XGPIO_CHANNEL0_OFFSET	0x0
+#define XGPIO_CHANNEL1_OFFSET	0x8
+
+#define XGPIO_GIER_OFFSET	0x11c /* Global Interrupt Enable */
+#define XGPIO_GIER_IE		BIT(31)
+#define XGPIO_IPISR_OFFSET	0x120 /* IP Interrupt Status */
+#define XGPIO_IPIER_OFFSET	0x128 /* IP Interrupt Enable */
+
+/* Read/Write access to the GPIO registers */
+#if defined(CONFIG_ARCH_ZYNQ) || defined(CONFIG_X86)
+# define xgpio_readreg(offset)		readl(offset)
+# define xgpio_writereg(offset, val)	writel(val, offset)
+#else
+# define xgpio_readreg(offset)		__raw_readl(offset)
+# define xgpio_writereg(offset, val)	__raw_writel(val, offset)
+#endif
+
+/**
+ * struct xgpio_instance - Stores information about GPIO device
+ * @gc: GPIO chip
+ * @regs: register block
+ * @hw_map: GPIO pin mapping on hardware side
+ * @sw_map: GPIO pin mapping on software side
+ * @state: GPIO write state shadow register
+ * @last_irq_read: GPIO read state register from last interrupt
+ * @dir: GPIO direction shadow register
+ * @gpio_lock: Lock used for synchronization
+ * @irq: IRQ used by GPIO device
+ * @irqchip: IRQ chip
+ * @enable: GPIO IRQ enable/disable bitfield
+ * @rising_edge: GPIO IRQ rising edge enable/disable bitfield
+ * @falling_edge: GPIO IRQ falling edge enable/disable bitfield
+ * @clk: clock resource for this driver
+ */
+struct xgpio_instance {
+	struct gpio_chip gc;
+	void __iomem *regs;
+	DECLARE_BITMAP(hw_map, 64);
+	DECLARE_BITMAP(sw_map, 64);
+	DECLARE_BITMAP(state, 64);
+	DECLARE_BITMAP(last_irq_read, 64);
+	DECLARE_BITMAP(dir, 64);
+	spinlock_t gpio_lock;	/* For serializing operations */
+	int irq;
+	DECLARE_BITMAP(enable, 64);
+	DECLARE_BITMAP(rising_edge, 64);
+	DECLARE_BITMAP(falling_edge, 64);
+	struct clk *clk;
+};
+
+static inline int xgpio_from_bit(struct xgpio_instance *chip, int bit)
+{
+	return bitmap_bitremap(bit, chip->hw_map, chip->sw_map, 64);
+}
+
+static inline int xgpio_to_bit(struct xgpio_instance *chip, int gpio)
+{
+	return bitmap_bitremap(gpio, chip->sw_map, chip->hw_map, 64);
+}
+
+static inline u32 xgpio_get_value32(const unsigned long *map, int bit)
+{
+	const size_t index = BIT_WORD(bit);
+	const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
+
+	return (map[index] >> offset) & 0xFFFFFFFFul;
+}
+
+static inline void xgpio_set_value32(unsigned long *map, int bit, u32 v)
+{
+	const size_t index = BIT_WORD(bit);
+	const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
+
+	map[index] &= ~(0xFFFFFFFFul << offset);
+	map[index] |= (unsigned long)v << offset;
+}
+
+static inline int xgpio_regoffset(struct xgpio_instance *chip, int ch)
+{
+	switch (ch) {
+	case 0:
+		return XGPIO_CHANNEL0_OFFSET;
+	case 1:
+		return XGPIO_CHANNEL1_OFFSET;
+	default:
+		return -EINVAL;
+	}
+}
+
+static void xgpio_read_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
+{
+	void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
+
+	xgpio_set_value32(a, bit, xgpio_readreg(addr));
+}
+
+static void xgpio_write_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
+{
+	void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
+
+	xgpio_writereg(addr, xgpio_get_value32(a, bit));
+}
+
+static void xgpio_read_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
+{
+	int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
+
+	for (bit = 0; bit <= lastbit ; bit += 32)
+		xgpio_read_ch(chip, reg, bit, a);
+}
+
+static void xgpio_write_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
+{
+	int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
+
+	for (bit = 0; bit <= lastbit ; bit += 32)
+		xgpio_write_ch(chip, reg, bit, a);
+}
+
+/**
+ * xgpio_get - Read the specified signal of the GPIO device.
+ * @gc:     Pointer to gpio_chip device structure.
+ * @gpio:   GPIO signal number.
+ *
+ * This function reads the specified signal of the GPIO device.
+ *
+ * Return:
+ * 0 if direction of GPIO signals is set as input otherwise it
+ * returns negative error value.
+ */
+static int xgpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+	struct xgpio_instance *chip = gpiochip_get_data(gc);
+	int bit = xgpio_to_bit(chip, gpio);
+	DECLARE_BITMAP(state, 64);
+
+	xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, state);
+
+	return test_bit(bit, state);
+}
+
+/**
+ * xgpio_set - Write the specified signal of the GPIO device.
+ * @gc:     Pointer to gpio_chip device structure.
+ * @gpio:   GPIO signal number.
+ * @val:    Value to be written to specified signal.
+ *
+ * This function writes the specified value in to the specified signal of the
+ * GPIO device.
+ */
+static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+	unsigned long flags;
+	struct xgpio_instance *chip = gpiochip_get_data(gc);
+	int bit = xgpio_to_bit(chip, gpio);
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	/* Write to GPIO signal and set its direction to output */
+	__assign_bit(bit, chip->state, val);
+
+	xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
+
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+}
+
+/**
+ * xgpio_set_multiple - Write the specified signals of the GPIO device.
+ * @gc:     Pointer to gpio_chip device structure.
+ * @mask:   Mask of the GPIOS to modify.
+ * @bits:   Value to be wrote on each GPIO
+ *
+ * This function writes the specified values into the specified signals of the
+ * GPIO devices.
+ */
+static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
+			       unsigned long *bits)
+{
+	DECLARE_BITMAP(hw_mask, 64);
+	DECLARE_BITMAP(hw_bits, 64);
+	DECLARE_BITMAP(state, 64);
+	unsigned long flags;
+	struct xgpio_instance *chip = gpiochip_get_data(gc);
+
+	bitmap_remap(hw_mask, mask, chip->sw_map, chip->hw_map, 64);
+	bitmap_remap(hw_bits, bits, chip->sw_map, chip->hw_map, 64);
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	bitmap_replace(state, chip->state, hw_bits, hw_mask, 64);
+
+	xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, state);
+
+	bitmap_copy(chip->state, state, 64);
+
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+}
+
+/**
+ * xgpio_dir_in - Set the direction of the specified GPIO signal as input.
+ * @gc:     Pointer to gpio_chip device structure.
+ * @gpio:   GPIO signal number.
+ *
+ * Return:
+ * 0 - if direction of GPIO signals is set as input
+ * otherwise it returns negative error value.
+ */
+static int xgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+	unsigned long flags;
+	struct xgpio_instance *chip = gpiochip_get_data(gc);
+	int bit = xgpio_to_bit(chip, gpio);
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	/* Set the GPIO bit in shadow register and set direction as input */
+	__set_bit(bit, chip->dir);
+	xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
+
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+
+	return 0;
+}
+
+/**
+ * xgpio_dir_out - Set the direction of the specified GPIO signal as output.
+ * @gc:     Pointer to gpio_chip device structure.
+ * @gpio:   GPIO signal number.
+ * @val:    Value to be written to specified signal.
+ *
+ * This function sets the direction of specified GPIO signal as output.
+ *
+ * Return:
+ * If all GPIO signals of GPIO chip is configured as input then it returns
+ * error otherwise it returns 0.
+ */
+static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+	unsigned long flags;
+	struct xgpio_instance *chip = gpiochip_get_data(gc);
+	int bit = xgpio_to_bit(chip, gpio);
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	/* Write state of GPIO signal */
+	__assign_bit(bit, chip->state, val);
+	xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
+
+	/* Clear the GPIO bit in shadow register and set direction as output */
+	__clear_bit(bit, chip->dir);
+	xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
+
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+
+	return 0;
+}
+
+/**
+ * xgpio_save_regs - Set initial values of GPIO pins
+ * @chip: Pointer to GPIO instance
+ */
+static void xgpio_save_regs(struct xgpio_instance *chip)
+{
+	xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, chip->state);
+	xgpio_write_ch_all(chip, XGPIO_TRI_OFFSET, chip->dir);
+}
+
+static int xgpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+	int ret;
+
+	ret = pm_runtime_get_sync(chip->parent);
+	/*
+	 * If the device is already active pm_runtime_get() will return 1 on
+	 * success, but gpio_request still needs to return 0.
+	 */
+	return ret < 0 ? ret : 0;
+}
+
+static void xgpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+	pm_runtime_put(chip->parent);
+}
+
+static int __maybe_unused xgpio_suspend(struct device *dev)
+{
+	struct xgpio_instance *gpio = dev_get_drvdata(dev);
+	struct irq_data *data = irq_get_irq_data(gpio->irq);
+
+	if (!data) {
+		dev_dbg(dev, "IRQ not connected\n");
+		return pm_runtime_force_suspend(dev);
+	}
+
+	if (!irqd_is_wakeup_set(data))
+		return pm_runtime_force_suspend(dev);
+
+	return 0;
+}
+
+/**
+ * xgpio_remove - Remove method for the GPIO device.
+ * @pdev: pointer to the platform device
+ *
+ * This function remove gpiochips and frees all the allocated resources.
+ *
+ * Return: 0 always
+ */
+static int xgpio_remove(struct platform_device *pdev)
+{
+	struct xgpio_instance *gpio = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	clk_disable_unprepare(gpio->clk);
+
+	return 0;
+}
+
+/**
+ * xgpio_irq_ack - Acknowledge a child GPIO interrupt.
+ * @irq_data: per IRQ and chip data passed down to chip functions
+ * This currently does nothing, but irq_ack is unconditionally called by
+ * handle_edge_irq and therefore must be defined.
+ */
+static void xgpio_irq_ack(struct irq_data *irq_data)
+{
+}
+
+static int __maybe_unused xgpio_resume(struct device *dev)
+{
+	struct xgpio_instance *gpio = dev_get_drvdata(dev);
+	struct irq_data *data = irq_get_irq_data(gpio->irq);
+
+	if (!data) {
+		dev_dbg(dev, "IRQ not connected\n");
+		return pm_runtime_force_resume(dev);
+	}
+
+	if (!irqd_is_wakeup_set(data))
+		return pm_runtime_force_resume(dev);
+
+	return 0;
+}
+
+static int __maybe_unused xgpio_runtime_suspend(struct device *dev)
+{
+	struct xgpio_instance *gpio = dev_get_drvdata(dev);
+
+	clk_disable(gpio->clk);
+
+	return 0;
+}
+
+static int __maybe_unused xgpio_runtime_resume(struct device *dev)
+{
+	struct xgpio_instance *gpio = dev_get_drvdata(dev);
+
+	return clk_enable(gpio->clk);
+}
+
+static const struct dev_pm_ops xgpio_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(xgpio_suspend, xgpio_resume)
+	SET_RUNTIME_PM_OPS(xgpio_runtime_suspend,
+			   xgpio_runtime_resume, NULL)
+};
+
+/**
+ * xgpio_irq_mask - Write the specified signal of the GPIO device.
+ * @irq_data: per IRQ and chip data passed down to chip functions
+ */
+static void xgpio_irq_mask(struct irq_data *irq_data)
+{
+	unsigned long flags;
+	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
+	int irq_offset = irqd_to_hwirq(irq_data);
+	int bit = xgpio_to_bit(chip, irq_offset);
+	u32 mask = BIT(bit / 32), temp;
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	__clear_bit(bit, chip->enable);
+
+	if (xgpio_get_value32(chip->enable, bit) == 0) {
+		/* Disable per channel interrupt */
+		temp = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
+		temp &= ~mask;
+		xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, temp);
+	}
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+
+	gpiochip_disable_irq(&chip->gc, irq_offset);
+}
+
+/**
+ * xgpio_irq_unmask - Write the specified signal of the GPIO device.
+ * @irq_data: per IRQ and chip data passed down to chip functions
+ */
+static void xgpio_irq_unmask(struct irq_data *irq_data)
+{
+	unsigned long flags;
+	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
+	int irq_offset = irqd_to_hwirq(irq_data);
+	int bit = xgpio_to_bit(chip, irq_offset);
+	u32 old_enable = xgpio_get_value32(chip->enable, bit);
+	u32 mask = BIT(bit / 32), val;
+
+	gpiochip_enable_irq(&chip->gc, irq_offset);
+
+	spin_lock_irqsave(&chip->gpio_lock, flags);
+
+	__set_bit(bit, chip->enable);
+
+	if (old_enable == 0) {
+		/* Clear any existing per-channel interrupts */
+		val = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
+		val &= mask;
+		xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, val);
+
+		/* Update GPIO IRQ read data before enabling interrupt*/
+		xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, chip->last_irq_read);
+
+		/* Enable per channel interrupt */
+		val = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
+		val |= mask;
+		xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, val);
+	}
+
+	spin_unlock_irqrestore(&chip->gpio_lock, flags);
+}
+
+/**
+ * xgpio_set_irq_type - Write the specified signal of the GPIO device.
+ * @irq_data: Per IRQ and chip data passed down to chip functions
+ * @type: Interrupt type that is to be set for the gpio pin
+ *
+ * Return:
+ * 0 if interrupt type is supported otherwise -EINVAL
+ */
+static int xgpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
+{
+	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
+	int irq_offset = irqd_to_hwirq(irq_data);
+	int bit = xgpio_to_bit(chip, irq_offset);
+
+	/*
+	 * The Xilinx GPIO hardware provides a single interrupt status
+	 * indication for any state change in a given GPIO channel (bank).
+	 * Therefore, only rising edge or falling edge triggers are
+	 * supported.
+	 */
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_BOTH:
+		__set_bit(bit, chip->rising_edge);
+		__set_bit(bit, chip->falling_edge);
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		__set_bit(bit, chip->rising_edge);
+		__clear_bit(bit, chip->falling_edge);
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		__clear_bit(bit, chip->rising_edge);
+		__set_bit(bit, chip->falling_edge);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	irq_set_handler_locked(irq_data, handle_edge_irq);
+	return 0;
+}
+
+/**
+ * xgpio_irqhandler - Gpio interrupt service routine
+ * @desc: Pointer to interrupt description
+ */
+static void xgpio_irqhandler(struct irq_desc *desc)
+{
+	struct xgpio_instance *chip = irq_desc_get_handler_data(desc);
+	struct gpio_chip *gc = &chip->gc;
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
+	DECLARE_BITMAP(rising, 64);
+	DECLARE_BITMAP(falling, 64);
+	DECLARE_BITMAP(all, 64);
+	int irq_offset;
+	u32 status;
+	u32 bit;
+
+	status = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
+	xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, status);
+
+	chained_irq_enter(irqchip, desc);
+
+	spin_lock(&chip->gpio_lock);
+
+	xgpio_read_ch_all(chip, XGPIO_DATA_OFFSET, all);
+
+	bitmap_complement(rising, chip->last_irq_read, 64);
+	bitmap_and(rising, rising, all, 64);
+	bitmap_and(rising, rising, chip->enable, 64);
+	bitmap_and(rising, rising, chip->rising_edge, 64);
+
+	bitmap_complement(falling, all, 64);
+	bitmap_and(falling, falling, chip->last_irq_read, 64);
+	bitmap_and(falling, falling, chip->enable, 64);
+	bitmap_and(falling, falling, chip->falling_edge, 64);
+
+	bitmap_copy(chip->last_irq_read, all, 64);
+	bitmap_or(all, rising, falling, 64);
+
+	spin_unlock(&chip->gpio_lock);
+
+	dev_dbg(gc->parent, "IRQ rising %*pb falling %*pb\n", 64, rising, 64, falling);
+
+	for_each_set_bit(bit, all, 64) {
+		irq_offset = xgpio_from_bit(chip, bit);
+		generic_handle_domain_irq(gc->irq.domain, irq_offset);
+	}
+
+	chained_irq_exit(irqchip, desc);
+}
+
+static const struct irq_chip xgpio_irq_chip = {
+	.name = "gpio-xilinx",
+	.irq_ack = xgpio_irq_ack,
+	.irq_mask = xgpio_irq_mask,
+	.irq_unmask = xgpio_irq_unmask,
+	.irq_set_type = xgpio_set_irq_type,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+/**
+ * xgpio_probe - Probe method for the GPIO device.
+ * @pdev: pointer to the platform device
+ *
+ * Return:
+ * It returns 0, if the driver is bound to the GPIO device, or
+ * a negative value if there is an error.
+ */
+static int xgpio_probe(struct platform_device *pdev)
+{
+	struct xgpio_instance *chip;
+	int status = 0;
+	struct device_node *np = pdev->dev.of_node;
+	u32 is_dual = 0;
+	u32 width[2];
+	u32 state[2];
+	u32 dir[2];
+	struct gpio_irq_chip *girq;
+	u32 temp;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, chip);
+
+	/* First, check if the device is dual-channel */
+	of_property_read_u32(np, "xlnx,is-dual", &is_dual);
+
+	/* Setup defaults */
+	memset32(width, 0, ARRAY_SIZE(width));
+	memset32(state, 0, ARRAY_SIZE(state));
+	memset32(dir, 0xFFFFFFFF, ARRAY_SIZE(dir));
+
+	/* Update GPIO state shadow register with default value */
+	of_property_read_u32(np, "xlnx,dout-default", &state[0]);
+	of_property_read_u32(np, "xlnx,dout-default-2", &state[1]);
+
+	bitmap_from_arr32(chip->state, state, 64);
+
+	/* Update GPIO direction shadow register with default value */
+	of_property_read_u32(np, "xlnx,tri-default", &dir[0]);
+	of_property_read_u32(np, "xlnx,tri-default-2", &dir[1]);
+
+	bitmap_from_arr32(chip->dir, dir, 64);
+
+	/*
+	 * Check device node and parent device node for device width
+	 * and assume default width of 32
+	 */
+	if (of_property_read_u32(np, "xlnx,gpio-width", &width[0]))
+		width[0] = 32;
+
+	if (width[0] > 32)
+		return -EINVAL;
+
+	if (is_dual && of_property_read_u32(np, "xlnx,gpio2-width", &width[1]))
+		width[1] = 32;
+
+	if (width[1] > 32)
+		return -EINVAL;
+
+	/* Setup software pin mapping */
+	bitmap_set(chip->sw_map, 0, width[0] + width[1]);
+
+	/* Setup hardware pin mapping */
+	bitmap_set(chip->hw_map,  0, width[0]);
+	bitmap_set(chip->hw_map, 32, width[1]);
+
+	spin_lock_init(&chip->gpio_lock);
+
+	chip->gc.base = -1;
+	chip->gc.ngpio = bitmap_weight(chip->hw_map, 64);
+	chip->gc.parent = &pdev->dev;
+	chip->gc.direction_input = xgpio_dir_in;
+	chip->gc.direction_output = xgpio_dir_out;
+	chip->gc.get = xgpio_get;
+	chip->gc.set = xgpio_set;
+	chip->gc.request = xgpio_request;
+	chip->gc.free = xgpio_free;
+	chip->gc.set_multiple = xgpio_set_multiple;
+
+	chip->gc.label = dev_name(&pdev->dev);
+
+	chip->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(chip->regs)) {
+		dev_err(&pdev->dev, "failed to ioremap memory resource\n");
+		return PTR_ERR(chip->regs);
+	}
+
+	chip->clk = devm_clk_get_optional(&pdev->dev, NULL);
+	if (IS_ERR(chip->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(chip->clk), "input clock not found.\n");
+
+	status = clk_prepare_enable(chip->clk);
+	if (status < 0) {
+		dev_err(&pdev->dev, "Failed to prepare clk\n");
+		return status;
+	}
+	pm_runtime_get_noresume(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	xgpio_save_regs(chip);
+
+	chip->irq = platform_get_irq_optional(pdev, 0);
+	if (chip->irq <= 0)
+		goto skip_irq;
+
+	/* Disable per-channel interrupts */
+	xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, 0);
+	/* Clear any existing per-channel interrupts */
+	temp = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
+	xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, temp);
+	/* Enable global interrupts */
+	xgpio_writereg(chip->regs + XGPIO_GIER_OFFSET, XGPIO_GIER_IE);
+
+	girq = &chip->gc.irq;
+	gpio_irq_chip_set_chip(girq, &xgpio_irq_chip);
+	girq->parent_handler = xgpio_irqhandler;
+	girq->num_parents = 1;
+	girq->parents = devm_kcalloc(&pdev->dev, 1,
+				     sizeof(*girq->parents),
+				     GFP_KERNEL);
+	if (!girq->parents) {
+		status = -ENOMEM;
+		goto err_pm_put;
+	}
+	girq->parents[0] = chip->irq;
+	girq->default_type = IRQ_TYPE_NONE;
+	girq->handler = handle_bad_irq;
+
+skip_irq:
+	status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
+	if (status) {
+		dev_err(&pdev->dev, "failed to add GPIO chip\n");
+		goto err_pm_put;
+	}
+
+	pm_runtime_put(&pdev->dev);
+	return 0;
+
+err_pm_put:
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+	clk_disable_unprepare(chip->clk);
+	return status;
+}
+
+static const struct of_device_id xgpio_of_match[] = {
+	{ .compatible = "xlnx,xps-gpio-1.00.a", },
+	{ /* end of list */ },
+};
+
+MODULE_DEVICE_TABLE(of, xgpio_of_match);
+
+static struct platform_driver xgpio_plat_driver = {
+	.probe		= xgpio_probe,
+	.remove		= xgpio_remove,
+	.driver		= {
+			.name = "gpio-xilinx",
+			.of_match_table	= xgpio_of_match,
+			.pm = &xgpio_dev_pm_ops,
+	},
+};
+
+static int __init xgpio_init(void)
+{
+	return platform_driver_register(&xgpio_plat_driver);
+}
+
+subsys_initcall(xgpio_init);
+
+static void __exit xgpio_exit(void)
+{
+	platform_driver_unregister(&xgpio_plat_driver);
+}
+module_exit(xgpio_exit);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx GPIO driver");
+MODULE_LICENSE("GPL");