target/linux/ar71xx/files/drivers/leds/leds-rb750.c

   1 /*
   2  * LED driver for the RouterBOARD 750
   3  *
   4  * Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/leds.h>
  15 #include <linux/slab.h>
  16
  17 #include <asm/mach-ar71xx/mach-rb750.h>
  18
  19 #define DRV_NAME        "leds-rb750"
  20
  21 struct rb750_led_dev {
  22         struct led_classdev     cdev;
  23         u32                     mask;
  24         int                     active_low;
  25 };
  26
  27 struct rb750_led_drvdata {
  28         struct rb750_led_dev    *led_devs;
  29         int                     num_leds;
  30 };
  31
  32 static inline struct rb750_led_dev *to_rbled(struct led_classdev *led_cdev)
  33 {
  34         return (struct rb750_led_dev *)container_of(led_cdev,
  35                 struct rb750_led_dev, cdev);
  36 }
  37
  38 static void rb750_led_brightness_set(struct led_classdev *led_cdev,
  39                                      enum led_brightness value)
  40 {
  41         struct rb750_led_dev *rbled = to_rbled(led_cdev);
  42         int level;
  43
  44         level = (value == LED_OFF) ? 0 : 1;
  45         level ^= rbled->active_low;
  46
  47         if (level)
  48                 rb750_latch_change(0, rbled->mask);
  49         else
  50                 rb750_latch_change(rbled->mask, 0);
  51 }
  52
  53 static int __devinit rb750_led_probe(struct platform_device *pdev)
  54 {
  55         struct rb750_led_platform_data *pdata;
  56         struct rb750_led_drvdata *drvdata;
  57         int ret = 0;
  58         int i;
  59
  60         pdata = pdev->dev.platform_data;
  61         if (!pdata)
  62                 return -EINVAL;
  63
  64         drvdata = kzalloc(sizeof(struct rb750_led_drvdata) +
  65                           sizeof(struct rb750_led_dev) * pdata->num_leds,
  66                           GFP_KERNEL);
  67         if (!drvdata)
  68                 return -ENOMEM;
  69
  70         drvdata->num_leds = pdata->num_leds;
  71         drvdata->led_devs = (struct rb750_led_dev *) &drvdata[1];
  72
  73         for (i = 0; i < drvdata->num_leds; i++) {
  74                 struct rb750_led_dev *rbled = &drvdata->led_devs[i];
  75                 struct rb750_led_data *led_data = &pdata->leds[i];
  76
  77                 rbled->cdev.name = led_data->name;
  78                 rbled->cdev.default_trigger = led_data->default_trigger;
  79                 rbled->cdev.brightness_set = rb750_led_brightness_set;
  80                 rbled->cdev.brightness = LED_OFF;
  81
  82                 rbled->mask = led_data->mask;
  83                 rbled->active_low = !!led_data->active_low;
  84
  85                 ret = led_classdev_register(&pdev->dev, &rbled->cdev);
  86                 if (ret)
  87                         goto err;
  88         }
  89
  90         platform_set_drvdata(pdev, drvdata);
  91         return 0;
  92
  93  err:
  94         for (i = i - 1; i >= 0; i--)
  95                 led_classdev_unregister(&drvdata->led_devs[i].cdev);
  96
  97         kfree(drvdata);
  98         return ret;
  99 }
 100
 101 static int __devexit rb750_led_remove(struct platform_device *pdev)
 102 {
 103         struct rb750_led_drvdata *drvdata;
 104         int i;
 105
 106         drvdata = platform_get_drvdata(pdev);
 107         for (i = 0; i < drvdata->num_leds; i++)
 108                 led_classdev_unregister(&drvdata->led_devs[i].cdev);
 109
 110         kfree(drvdata);
 111         return 0;
 112 }
 113
 114 static struct platform_driver rb750_led_driver = {
 115         .probe          = rb750_led_probe,
 116         .remove         = __devexit_p(rb750_led_remove),
 117         .driver         = {
 118                 .name   = DRV_NAME,
 119                 .owner  = THIS_MODULE,
 120         },
 121 };
 122
 123 MODULE_ALIAS("platform:leds-rb750");
 124
 125 static int __init rb750_led_init(void)
 126 {
 127         return platform_driver_register(&rb750_led_driver);
 128 }
 129
 130 static void __exit rb750_led_exit(void)
 131 {
 132         platform_driver_unregister(&rb750_led_driver);
 133 }
 134
 135 module_init(rb750_led_init);
 136 module_exit(rb750_led_exit);
 137
 138 MODULE_DESCRIPTION(DRV_NAME);
 139 MODULE_DESCRIPTION("LED driver for the RouterBOARD 750");
 140 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 141 MODULE_LICENSE("GPL v2");