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 at openwrt.org>
   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_FULL:
  70                 gpio_direction_output(pdata->gpio, pdata->value_on);
  71                 break;
  72         case LED_OFF:
  73                 gpio_direction_output(pdata->gpio, pdata->value_off);
  74                 break;
  75         default:
  76                 gpio_direction_output(pdata->gpio, brightness);
  77                 break;
  78         }
  79 }
  80
  81 static int __devinit gpio_led_probe(struct platform_device *dev)
  82 {
  83         struct gpio_led_platform_data *pdata;
  84         struct gpio_led_device *led;
  85         int ret;
  86
  87         pdata = dev->dev.platform_data;
  88         if (pdata == NULL) {
  89                 dev_err(&dev->dev, "no platform data, id=%d\n", dev->id);
  90                 ret = -EINVAL;
  91                 goto err;
  92         }
  93
  94         if (pdata->name == NULL) {
  95                 dev_err(&dev->dev, "no led name specified\n");
  96                 ret = -EINVAL;
  97                 goto err;
  98         }
  99
 100         ret = gpio_request(pdata->gpio, pdata->name);
 101         if (ret) {
 102                 dev_err(&dev->dev, "gpio_request failed\n");
 103                 goto err;
 104         }
 105
 106         led = kzalloc(sizeof(*led), GFP_KERNEL);
 107         if (led == NULL) {
 108                 dev_err(&dev->dev, "no memory for device");
 109                 ret = -ENOMEM;
 110                 goto err_free_gpio;
 111         }
 112
 113         platform_set_drvdata(dev, led);
 114         led->pdata = pdata;
 115         led->cdev.name = pdata->name;
 116         led->cdev.brightness_set = gpio_led_set;
 117 #ifdef CONFIG_LEDS_TRIGGERS
 118         led->cdev.default_trigger = pdata->trigger;
 119 #endif
 120
 121         ret = led_classdev_register(&dev->dev, &led->cdev);
 122         if (ret < 0) {
 123                 dev_err(&dev->dev, "led_classdev_register failed");
 124                 goto err_free_led;
 125         }
 126
 127         return 0;
 128
 129 err_free_led:
 130         kfree(led);
 131 err_free_gpio:
 132         gpio_free(pdata->gpio);
 133 err:
 134         return ret;
 135 }
 136
 137 static int __devexit gpio_led_remove(struct platform_device *dev)
 138 {
 139         struct gpio_led_device *led;
 140         struct gpio_led_platform_data *pdata;
 141
 142         pdata = dev->dev.platform_data;
 143
 144         led = pdev_to_led(dev);
 145         led_classdev_unregister(&led->cdev);
 146         kfree(led);
 147
 148         gpio_free(pdata->gpio);
 149
 150         return 0;
 151 }
 152
 153 #ifdef CONFIG_PM
 154 static int gpio_led_suspend(struct platform_device *dev,
 155                 pm_message_t state)
 156 {
 157         struct gpio_led_device *led;
 158
 159         led = pdev_to_led(dev);
 160         led_classdev_suspend(&led->cdev);
 161
 162         return 0;
 163 }
 164
 165 static int gpio_led_resume(struct platform_device *dev)
 166 {
 167         struct gpio_led_device *led;
 168
 169         led = pdev_to_led(dev);
 170         led_classdev_resume(&led->cdev);
 171
 172         return 0;
 173 }
 174 #endif /* CONFIG_PM */
 175
 176 static struct platform_driver gpio_led_driver = {
 177         .probe          = gpio_led_probe,
 178         .remove         = __devexit_p(gpio_led_remove),
 179 #ifdef CONFIG_PM
 180         .suspend        = gpio_led_suspend,
 181         .resume         = gpio_led_resume,
 182 #endif
 183         .driver         = {
 184                 .name           = DRV_NAME,
 185                 .owner          = THIS_MODULE,
 186         },
 187 };
 188
 189 static int __init gpio_led_init(void)
 190 {
 191         int ret;
 192
 193         ret = platform_driver_register(&gpio_led_driver);
 194         if (ret)
 195                 printk(KERN_ALERT DRV_DESC " register failed\n");
 196         else
 197                 printk(KERN_INFO DRV_DESC " registered\n");
 198
 199         return ret;
 200 }
 201
 202 static void __exit gpio_led_exit(void)
 203 {
 204         platform_driver_unregister(&gpio_led_driver);
 205 }
 206
 207 module_init(gpio_led_init);
 208 module_exit(gpio_led_exit);
 209
 210 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 211 MODULE_DESCRIPTION(DRV_DESC);
 212 MODULE_LICENSE("GPL");