swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: e49d033bddf5b565044e2abe4241353959bc9120 authored by Linus Torvalds on 04 April 2021, 21:15:36 UTC
Linux 5.12-rc6
Linux 5.12-rc6
Tip revision: e49d033
gpio-xilinx.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Xilinx gpio driver for xps/axi_gpio IP.
*
* Copyright 2008 - 2013 Xilinx, Inc.
*/
#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_device.h>
#include <linux/of_platform.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_CHANNEL_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
* @gpio_width: GPIO width for every channel
* @gpio_state: GPIO write state shadow register
* @gpio_last_irq_read: GPIO read state register from last interrupt
* @gpio_dir: GPIO direction shadow register
* @gpio_lock: Lock used for synchronization
* @irq: IRQ used by GPIO device
* @irqchip: IRQ chip
* @irq_enable: GPIO IRQ enable/disable bitfield
* @irq_rising_edge: GPIO IRQ rising edge enable/disable bitfield
* @irq_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;
unsigned int gpio_width[2];
u32 gpio_state[2];
u32 gpio_last_irq_read[2];
u32 gpio_dir[2];
spinlock_t gpio_lock; /* For serializing operations */
int irq;
struct irq_chip irqchip;
u32 irq_enable[2];
u32 irq_rising_edge[2];
u32 irq_falling_edge[2];
struct clk *clk;
};
static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
{
if (gpio >= chip->gpio_width[0])
return 1;
return 0;
}
static inline int xgpio_regoffset(struct xgpio_instance *chip, int gpio)
{
if (xgpio_index(chip, gpio))
return XGPIO_CHANNEL_OFFSET;
return 0;
}
static inline int xgpio_offset(struct xgpio_instance *chip, int gpio)
{
if (xgpio_index(chip, gpio))
return gpio - chip->gpio_width[0];
return gpio;
}
/**
* 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);
u32 val;
val = xgpio_readreg(chip->regs + XGPIO_DATA_OFFSET +
xgpio_regoffset(chip, gpio));
return !!(val & BIT(xgpio_offset(chip, gpio)));
}
/**
* 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 index = xgpio_index(chip, gpio);
int offset = xgpio_offset(chip, gpio);
spin_lock_irqsave(&chip->gpio_lock, flags);
/* Write to GPIO signal and set its direction to output */
if (val)
chip->gpio_state[index] |= BIT(offset);
else
chip->gpio_state[index] &= ~BIT(offset);
xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
xgpio_regoffset(chip, gpio), chip->gpio_state[index]);
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)
{
unsigned long flags;
struct xgpio_instance *chip = gpiochip_get_data(gc);
int index = xgpio_index(chip, 0);
int offset, i;
spin_lock_irqsave(&chip->gpio_lock, flags);
/* Write to GPIO signals */
for (i = 0; i < gc->ngpio; i++) {
if (*mask == 0)
break;
/* Once finished with an index write it out to the register */
if (index != xgpio_index(chip, i)) {
xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
index * XGPIO_CHANNEL_OFFSET,
chip->gpio_state[index]);
spin_unlock_irqrestore(&chip->gpio_lock, flags);
index = xgpio_index(chip, i);
spin_lock_irqsave(&chip->gpio_lock, flags);
}
if (__test_and_clear_bit(i, mask)) {
offset = xgpio_offset(chip, i);
if (test_bit(i, bits))
chip->gpio_state[index] |= BIT(offset);
else
chip->gpio_state[index] &= ~BIT(offset);
}
}
xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]);
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 index = xgpio_index(chip, gpio);
int offset = xgpio_offset(chip, gpio);
spin_lock_irqsave(&chip->gpio_lock, flags);
/* Set the GPIO bit in shadow register and set direction as input */
chip->gpio_dir[index] |= BIT(offset);
xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
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 index = xgpio_index(chip, gpio);
int offset = xgpio_offset(chip, gpio);
spin_lock_irqsave(&chip->gpio_lock, flags);
/* Write state of GPIO signal */
if (val)
chip->gpio_state[index] |= BIT(offset);
else
chip->gpio_state[index] &= ~BIT(offset);
xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
xgpio_regoffset(chip, gpio), chip->gpio_state[index]);
/* Clear the GPIO bit in shadow register and set direction as output */
chip->gpio_dir[index] &= ~BIT(offset);
xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET +
xgpio_regoffset(chip, gpio), chip->gpio_dir[index]);
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_writereg(chip->regs + XGPIO_DATA_OFFSET, chip->gpio_state[0]);
xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET, chip->gpio_dir[0]);
if (!chip->gpio_width[1])
return;
xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET + XGPIO_CHANNEL_OFFSET,
chip->gpio_state[1]);
xgpio_writereg(chip->regs + XGPIO_TRI_OFFSET + XGPIO_CHANNEL_OFFSET,
chip->gpio_dir[1]);
}
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_err(dev, "irq_get_irq_data() failed\n");
return -EINVAL;
}
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_err(dev, "irq_get_irq_data() failed\n");
return -EINVAL;
}
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 platform_device *pdev = to_platform_device(dev);
struct xgpio_instance *gpio = platform_get_drvdata(pdev);
clk_disable(gpio->clk);
return 0;
}
static int __maybe_unused xgpio_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct xgpio_instance *gpio = platform_get_drvdata(pdev);
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 index = xgpio_index(chip, irq_offset);
int offset = xgpio_offset(chip, irq_offset);
spin_lock_irqsave(&chip->gpio_lock, flags);
chip->irq_enable[index] &= ~BIT(offset);
if (!chip->irq_enable[index]) {
/* Disable per channel interrupt */
u32 temp = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
temp &= ~BIT(index);
xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, temp);
}
spin_unlock_irqrestore(&chip->gpio_lock, flags);
}
/**
* 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 index = xgpio_index(chip, irq_offset);
int offset = xgpio_offset(chip, irq_offset);
u32 old_enable = chip->irq_enable[index];
spin_lock_irqsave(&chip->gpio_lock, flags);
chip->irq_enable[index] |= BIT(offset);
if (!old_enable) {
/* Clear any existing per-channel interrupts */
u32 val = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET) &
BIT(index);
if (val)
xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, val);
/* Update GPIO IRQ read data before enabling interrupt*/
val = xgpio_readreg(chip->regs + XGPIO_DATA_OFFSET +
index * XGPIO_CHANNEL_OFFSET);
chip->gpio_last_irq_read[index] = val;
/* Enable per channel interrupt */
val = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
val |= BIT(index);
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 index = xgpio_index(chip, irq_offset);
int offset = xgpio_offset(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:
chip->irq_rising_edge[index] |= BIT(offset);
chip->irq_falling_edge[index] |= BIT(offset);
break;
case IRQ_TYPE_EDGE_RISING:
chip->irq_rising_edge[index] |= BIT(offset);
chip->irq_falling_edge[index] &= ~BIT(offset);
break;
case IRQ_TYPE_EDGE_FALLING:
chip->irq_rising_edge[index] &= ~BIT(offset);
chip->irq_falling_edge[index] |= BIT(offset);
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 irq_chip *irqchip = irq_desc_get_chip(desc);
u32 num_channels = chip->gpio_width[1] ? 2 : 1;
u32 offset = 0, index;
u32 status = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, status);
chained_irq_enter(irqchip, desc);
for (index = 0; index < num_channels; index++) {
if ((status & BIT(index))) {
unsigned long rising_events, falling_events, all_events;
unsigned long flags;
u32 data, bit;
unsigned int irq;
spin_lock_irqsave(&chip->gpio_lock, flags);
data = xgpio_readreg(chip->regs + XGPIO_DATA_OFFSET +
index * XGPIO_CHANNEL_OFFSET);
rising_events = data &
~chip->gpio_last_irq_read[index] &
chip->irq_enable[index] &
chip->irq_rising_edge[index];
falling_events = ~data &
chip->gpio_last_irq_read[index] &
chip->irq_enable[index] &
chip->irq_falling_edge[index];
dev_dbg(chip->gc.parent,
"IRQ chan %u rising 0x%lx falling 0x%lx\n",
index, rising_events, falling_events);
all_events = rising_events | falling_events;
chip->gpio_last_irq_read[index] = data;
spin_unlock_irqrestore(&chip->gpio_lock, flags);
for_each_set_bit(bit, &all_events, 32) {
irq = irq_find_mapping(chip->gc.irq.domain,
offset + bit);
generic_handle_irq(irq);
}
}
offset += chip->gpio_width[index];
}
chained_irq_exit(irqchip, desc);
}
/**
* xgpio_of_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 cells = 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);
/* Update GPIO state shadow register with default value */
if (of_property_read_u32(np, "xlnx,dout-default", &chip->gpio_state[0]))
chip->gpio_state[0] = 0x0;
/* Update GPIO direction shadow register with default value */
if (of_property_read_u32(np, "xlnx,tri-default", &chip->gpio_dir[0]))
chip->gpio_dir[0] = 0xFFFFFFFF;
/* Update cells with gpio-cells value */
if (of_property_read_u32(np, "#gpio-cells", &cells))
dev_dbg(&pdev->dev, "Missing gpio-cells property\n");
if (cells != 2) {
dev_err(&pdev->dev, "#gpio-cells mismatch\n");
return -EINVAL;
}
/*
* 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", &chip->gpio_width[0]))
chip->gpio_width[0] = 32;
if (chip->gpio_width[0] > 32)
return -EINVAL;
spin_lock_init(&chip->gpio_lock);
if (of_property_read_u32(np, "xlnx,is-dual", &is_dual))
is_dual = 0;
if (is_dual) {
/* Update GPIO state shadow register with default value */
if (of_property_read_u32(np, "xlnx,dout-default-2",
&chip->gpio_state[1]))
chip->gpio_state[1] = 0x0;
/* Update GPIO direction shadow register with default value */
if (of_property_read_u32(np, "xlnx,tri-default-2",
&chip->gpio_dir[1]))
chip->gpio_dir[1] = 0xFFFFFFFF;
/*
* Check device node and parent device node for device width
* and assume default width of 32
*/
if (of_property_read_u32(np, "xlnx,gpio2-width",
&chip->gpio_width[1]))
chip->gpio_width[1] = 32;
if (chip->gpio_width[1] > 32)
return -EINVAL;
}
chip->gc.base = -1;
chip->gc.ngpio = chip->gpio_width[0] + chip->gpio_width[1];
chip->gc.parent = &pdev->dev;
chip->gc.direction_input = xgpio_dir_in;
chip->gc.direction_output = xgpio_dir_out;
chip->gc.of_gpio_n_cells = cells;
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;
chip->irqchip.name = "gpio-xilinx";
chip->irqchip.irq_ack = xgpio_irq_ack;
chip->irqchip.irq_mask = xgpio_irq_mask;
chip->irqchip.irq_unmask = xgpio_irq_unmask;
chip->irqchip.irq_set_type = xgpio_set_irq_type;
/* 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;
girq->chip = &chip->irqchip;
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");