target/linux/adm5120-2.6/files/drivers/leds/leds-gpio.c

   1 /*
   2  *  $Id$
   3  *
   4  *  Driver for LEDs connected to GPIO lines
   5  *
   6  *  Copyright (C) 2007 OpenWrt.org
   7  *  Copyright (C) 2007 Gabor Juhos <juhosg@freemail.hu>
   8  *
   9  *  This file was derived from:
  10  *    /drivers/led/leds-s3c24xx.c
  11  *    (c) 2006 Simtec Electronics, Ben Dooks <ben@simtec.co.uk>
  12  *
  13  *  This program is free software; you can redistribute it and/or
  14  *  modify it under the terms of the GNU General Public License
  15  *  as published by the Free Software Foundation; either version 2
  16  *  of the License, or (at your option) any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful,
  19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *  GNU General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License
  24  *  along with this program; if not, write to the
  25  *  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  26  *  Boston, MA  02110-1301, USA.
  27  *
  28  */
  29
  30 #include <linux/kernel.h>
  31 #include <linux/init.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/leds.h>
  34 #include <linux/err.h>
  35
  36 #include <linux/gpio_leds.h>
  37
  38 #include <asm/io.h>
  39 #include <asm/gpio.h>
  40
  41 #define DRV_NAME "gpio-led"
  42 #define DRV_DESC "GPIO LEDs driver"
  43
  44 struct gpio_led_device {
  45         struct led_classdev cdev;
  46         struct gpio_led_platform_data *pdata;
  47 };
  48
  49 static inline struct gpio_led_device *pdev_to_led(struct platform_device *dev)
  50 {
  51         return platform_get_drvdata(dev);
  52 }
  53
  54 static inline struct gpio_led_device *class_to_led(struct led_classdev *led_cdev)
  55 {
  56         return container_of(led_cdev, struct gpio_led_device, cdev);
  57 }
  58
  59 static void gpio_led_set(struct led_classdev *led_cdev,
  60                             enum led_brightness brightness)
  61 {
  62         struct gpio_led_device *led;
  63         struct gpio_led_platform_data *pdata;
  64
  65         led = class_to_led(led_cdev);
  66         pdata = led->pdata;
  67
  68         switch (brightness) {
  69         case LED_OFF:
  70                 gpio_direction_output(pdata->gpio, pdata->value_off);
  71                 break;
  72         default:
  73                 gpio_direction_output(pdata->gpio, pdata->value_on);
  74                 break;
  75         }
  76 }
  77
  78 static int __devinit gpio_led_probe(struct platform_device *dev)
  79 {
  80         struct gpio_led_platform_data *pdata;
  81         struct gpio_led_device *led;
  82         int ret;
  83
  84         pdata = dev->dev.platform_data;
  85         if (pdata == NULL) {
  86                 dev_err(&dev->dev, "no platform data, id=%d\n", dev->id);
  87                 ret = -EINVAL;
  88                 goto err;
  89         }
  90
  91         if (pdata->name == NULL) {
  92                 dev_err(&dev->dev, "no led name specified\n");
  93                 ret = -EINVAL;
  94                 goto err;
  95         }
  96
  97         ret = gpio_request(pdata->gpio, pdata->name);
  98         if (ret) {
  99                 dev_err(&dev->dev, "gpio_request failed\n");
 100                 goto err;
 101         }
 102
 103         led = kzalloc(sizeof(*led), GFP_KERNEL);
 104         if (led == NULL) {
 105                 dev_err(&dev->dev, "no memory for device");
 106                 ret = -ENOMEM;
 107                 goto err_free_gpio;
 108         }
 109
 110         platform_set_drvdata(dev, led);
 111         led->pdata = pdata;
 112         led->cdev.name = pdata->name;
 113         led->cdev.brightness_set = gpio_led_set;
 114 #ifdef CONFIG_LEDS_TRIGGERS
 115         led->cdev.default_trigger = pdata->trigger;
 116 #endif
 117
 118         ret = led_classdev_register(&dev->dev, &led->cdev);
 119         if (ret < 0) {
 120                 dev_err(&dev->dev, "led_classdev_register failed");
 121                 goto err_free_led;
 122         }
 123
 124         return 0;
 125
 126 err_free_led:
 127         kfree(led);
 128 err_free_gpio:
 129         gpio_free(pdata->gpio);
 130 err:
 131         return ret;
 132 }
 133
 134 static int __devexit gpio_led_remove(struct platform_device *dev)
 135 {
 136         struct gpio_led_device *led;
 137         struct gpio_led_platform_data *pdata;
 138
 139         pdata = dev->dev.platform_data;
 140
 141         led = pdev_to_led(dev);
 142         led_classdev_unregister(&led->cdev);
 143         kfree(led);
 144
 145         gpio_free(pdata->gpio);
 146
 147         return 0;
 148 }
 149
 150 #ifdef CONFIG_PM
 151 static int gpio_led_suspend(struct platform_device *dev,
 152                 pm_message_t state)
 153 {
 154         struct gpio_led_device *led;
 155
 156         led = pdev_to_led(dev);
 157         led_classdev_suspend(&led->cdev);
 158
 159         return 0;
 160 }
 161
 162 static int gpio_led_resume(struct platform_device *dev)
 163 {
 164         struct gpio_led_device *led;
 165
 166         led = pdev_to_led(dev);
 167         led_classdev_resume(&led->cdev);
 168
 169         return 0;
 170 }
 171 #endif /* CONFIG_PM */
 172
 173 static struct platform_driver gpio_led_driver = {
 174         .probe          = gpio_led_probe,
 175         .remove         = __devexit_p(gpio_led_remove),
 176 #ifdef CONFIG_PM
 177         .suspend        = gpio_led_suspend,
 178         .resume         = gpio_led_resume,
 179 #endif
 180         .driver         = {
 181                 .name           = DRV_NAME,
 182                 .owner          = THIS_MODULE,
 183         },
 184 };
 185
 186 static int __init gpio_led_init(void)
 187 {
 188         int ret;
 189
 190         ret = platform_driver_register(&gpio_led_driver);
 191         if (ret)
 192                 printk(KERN_ALERT DRV_DESC " register failed\n");
 193         else
 194                 printk(KERN_INFO DRV_DESC " registered\n");
 195
 196         return ret;
 197 }
 198
 199 static void __exit gpio_led_exit(void)
 200 {
 201         platform_driver_unregister(&gpio_led_driver);
 202 }
 203
 204 module_init(gpio_led_init);
 205 module_exit(gpio_led_exit);
 206
 207 MODULE_AUTHOR("Gabor Juhos <juhosg@freemail.hu>");
 208 MODULE_DESCRIPTION(DRV_DESC);
 209 MODULE_LICENSE("GPL");