target/linux/adm5120-2.6/files/drivers/char/adm5120_gpio.c

   1 /*
   2  *      ADM5120 LED (GPIO) driver
   3  *
   4  *      Copyright (C) Jeroen Vreeken (pe1rxq@amsat.org), 2005
   5  *      Copyright (C) OpenWrt.org, Florian Fainelli <florian@openwrt.org>, 2007
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License version 2 as
   9  *      published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/leds.h>
  16
  17 #define GPIO_IO        ((unsigned long *)0xb20000b8)
  18
  19 static void adm5120_led_set(struct led_classdev *led_cdev, enum led_brightness brightness)
  20 {
  21         if (brightness)
  22                 *GPIO_IO=(*GPIO_IO & 0x00ffffff) | (brightness << 24);
  23         else
  24                 *GPIO_IO=(*GPIO_IO & 0x00ffffff) | (0 << 24);
  25 }
  26
  27 static struct led_classdev adm5120_gpio_led = {
  28         .name           = "adm5120:led",
  29         .brightness_set = adm5120_led_set,
  30 };
  31
  32 static int __init adm5120_led_init(void)
  33 {
  34         int ret = led_classdev_register(NULL, &adm5120_gpio_led);
  35
  36         if (ret < 0)
  37                 printk(KERN_WARNING "adm5120: unable to register LED device\n");
  38
  39         return ret;
  40 }
  41
  42 static void __exit adm5120_led_exit(void)
  43 {
  44         led_classdev_unregister(&adm5120_gpio_led);
  45 }
  46
  47 module_init(adm5120_led_init);
  48 module_exit(adm5120_led_exit);
  49
  50 MODULE_DESCRIPTION("ADM5120 LED driver");
  51 MODULE_AUTHOR("Jeroen Vreeken, OpenWrt.org");
  52 MODULE_LICENSE("GPL");