1. 根目录:
2. drivers
3. gpio
4. ucb1400_gpio.c

/*
 * Philips UCB1400 GPIO driver
 *
 * Author: Marek Vasut <marek.vasut@gmail.com>
 *
 * 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.
 *
 */

#include <linux/module.h>
#include <linux/ucb1400.h>

struct ucb1400_gpio_data *ucbdata;

static int ucb1400_gpio_dir_in(struct gpio_chip *gc, unsigned off)
{
	struct ucb1400_gpio *gpio;
	gpio = container_of(gc, struct ucb1400_gpio, gc);
	ucb1400_gpio_set_direction(gpio->ac97, off, 0);
	return 0;
}

static int ucb1400_gpio_dir_out(struct gpio_chip *gc, unsigned off, int val)
{
	struct ucb1400_gpio *gpio;
	gpio = container_of(gc, struct ucb1400_gpio, gc);
	ucb1400_gpio_set_direction(gpio->ac97, off, 1);
	ucb1400_gpio_set_value(gpio->ac97, off, val);
	return 0;
}

static int ucb1400_gpio_get(struct gpio_chip *gc, unsigned off)
{
	struct ucb1400_gpio *gpio;
	gpio = container_of(gc, struct ucb1400_gpio, gc);
	return ucb1400_gpio_get_value(gpio->ac97, off);
}

static void ucb1400_gpio_set(struct gpio_chip *gc, unsigned off, int val)
{
	struct ucb1400_gpio *gpio;
	gpio = container_of(gc, struct ucb1400_gpio, gc);
	ucb1400_gpio_set_value(gpio->ac97, off, val);
}

static int ucb1400_gpio_probe(struct platform_device *dev)
{
	struct ucb1400_gpio *ucb = dev->dev.platform_data;
	int err = 0;

	if (!(ucbdata && ucbdata->gpio_offset)) {
		err = -EINVAL;
		goto err;
	}

	platform_set_drvdata(dev, ucb);

	ucb->gc.label = "ucb1400_gpio";
	ucb->gc.base = ucbdata->gpio_offset;
	ucb->gc.ngpio = 10;
	ucb->gc.owner = THIS_MODULE;

	ucb->gc.direction_input = ucb1400_gpio_dir_in;
	ucb->gc.direction_output = ucb1400_gpio_dir_out;
	ucb->gc.get = ucb1400_gpio_get;
	ucb->gc.set = ucb1400_gpio_set;
	ucb->gc.can_sleep = 1;

	err = gpiochip_add(&ucb->gc);
	if (err)
		goto err;

	if (ucbdata && ucbdata->gpio_setup)
		err = ucbdata->gpio_setup(&dev->dev, ucb->gc.ngpio);

err:
	return err;

}

static int ucb1400_gpio_remove(struct platform_device *dev)
{
	int err = 0;
	struct ucb1400_gpio *ucb = platform_get_drvdata(dev);

	if (ucbdata && ucbdata->gpio_teardown) {
		err = ucbdata->gpio_teardown(&dev->dev, ucb->gc.ngpio);
		if (err)
			return err;
	}

	err = gpiochip_remove(&ucb->gc);
	return err;
}

static struct platform_driver ucb1400_gpio_driver = {
	.probe	= ucb1400_gpio_probe,
	.remove	= ucb1400_gpio_remove,
	.driver	= {
		.name	= "ucb1400_gpio"
	},
};

static int __init ucb1400_gpio_init(void)
{
	return platform_driver_register(&ucb1400_gpio_driver);
}

static void __exit ucb1400_gpio_exit(void)
{
	platform_driver_unregister(&ucb1400_gpio_driver);
}

void __init ucb1400_gpio_set_data(struct ucb1400_gpio_data *data)
{
	ucbdata = data;
}

module_init(ucb1400_gpio_init);
module_exit(ucb1400_gpio_exit);

MODULE_DESCRIPTION("Philips UCB1400 GPIO driver");
MODULE_LICENSE("GPL");