linux-imx

/*

 * leds-netxbig.c - Driver for the 2Big and 5Big Network series LEDs

 *

 * Copyright (C) 2010 LaCie

 *

 * Author: Simon Guinot <sguinot@lacie.com>

 *

 * 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.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

​

#include <linux/module.h>

#include <linux/irq.h>

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <linux/platform_device.h>

#include <linux/gpio.h>

#include <linux/of_gpio.h>

#include <linux/leds.h>

#include <linux/platform_data/leds-kirkwood-netxbig.h>

​

/*

 * GPIO extension bus.

 */

​

static DEFINE_SPINLOCK(gpio_ext_lock);

​

static void gpio_ext_set_addr(struct netxbig_gpio_ext *gpio_ext, int addr)

{

    int pin;

​

    for (pin = 0; pin < gpio_ext->num_addr; pin++)

        gpio_set_value(gpio_ext->addr[pin], (addr >> pin) & 1);

}

​

static void gpio_ext_set_data(struct netxbig_gpio_ext *gpio_ext, int data)

{

    int pin;

​

    for (pin = 0; pin < gpio_ext->num_data; pin++)

        gpio_set_value(gpio_ext->data[pin], (data >> pin) & 1);

}

​

static void gpio_ext_enable_select(struct netxbig_gpio_ext *gpio_ext)

{

    /* Enable select is done on the raising edge. */

    gpio_set_value(gpio_ext->enable, 0);

    gpio_set_value(gpio_ext->enable, 1);

}

​

static void gpio_ext_set_value(struct netxbig_gpio_ext *gpio_ext,

                   int addr, int value)

{

    unsigned long flags;

​

    spin_lock_irqsave(&gpio_ext_lock, flags);

    gpio_ext_set_addr(gpio_ext, addr);

    gpio_ext_set_data(gpio_ext, value);

    gpio_ext_enable_select(gpio_ext);

    spin_unlock_irqrestore(&gpio_ext_lock, flags);

}

​

static int gpio_ext_init(struct platform_device *pdev,

             struct netxbig_gpio_ext *gpio_ext)

{

    int err;

    int i;

​

    if (unlikely(!gpio_ext))

        return -EINVAL;

​

    /* Configure address GPIOs. */

    for (i = 0; i < gpio_ext->num_addr; i++) {

        err = devm_gpio_request_one(&pdev->dev, gpio_ext->addr[i],

                        GPIOF_OUT_INIT_LOW,

                        "GPIO extension addr");

        if (err)

            return err;

    }

    /* Configure data GPIOs. */

    for (i = 0; i < gpio_ext->num_data; i++) {