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/module.h>
  13 #include <linux/init.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/leds.h>
  16 #include <linux/slab.h>
  17
  18 #include <asm/mach-ath79/mach-rb750.h>
  19
  20 #define DRV_NAME        "leds-rb750"
  21
  22 struct rb750_led_dev {
  23         struct led_classdev     cdev;
  24         u32                     mask;
  25         int                     active_low;
  26         void                    (*latch_change)(u32 clear, u32 set);
  27 };
  28
  29 struct rb750_led_drvdata {
  30         struct rb750_led_dev    *led_devs;
  31         int                     num_leds;
  32 };
  33
  34 static inline struct rb750_led_dev *to_rbled(struct led_classdev *led_cdev)
  35 {
  36         return (struct rb750_led_dev *)container_of(led_cdev,
  37                 struct rb750_led_dev, cdev);
  38 }
  39
  40 static void rb750_led_brightness_set(struct led_classdev *led_cdev,
  41                                      enum led_brightness value)
  42 {
  43         struct rb750_led_dev *rbled = to_rbled(led_cdev);
  44         int level;
  45
  46         level = (value == LED_OFF) ? 0 : 1;
  47         level ^= rbled->active_low;
  48
  49         if (level)
  50                 rbled->latch_change(0, rbled->mask);
  51         else
  52                 rbled->latch_change(rbled->mask, 0);
  53 }
  54
  55 static int rb750_led_probe(struct platform_device *pdev)
  56 {
  57         struct rb750_led_platform_data *pdata;
  58         struct rb750_led_drvdata *drvdata;
  59         int ret = 0;
  60         int i;
  61
  62         pdata = pdev->dev.platform_data;
  63         if (!pdata)
  64                 return -EINVAL;
  65
  66         drvdata = kzalloc(sizeof(struct rb750_led_drvdata) +
  67                           sizeof(struct rb750_led_dev) * pdata->num_leds,
  68                           GFP_KERNEL);
  69         if (!drvdata)
  70                 return -ENOMEM;
  71
  72         drvdata->num_leds = pdata->num_leds;
  73         drvdata->led_devs = (struct rb750_led_dev *) &drvdata[1];
  74
  75         for (i = 0; i < drvdata->num_leds; i++) {
  76                 struct rb750_led_dev *rbled = &drvdata->led_devs[i];
  77                 struct rb750_led_data *led_data = &pdata->leds[i];
  78
  79                 rbled->cdev.name = led_data->name;
  80                 rbled->cdev.default_trigger = led_data->default_trigger;
  81                 rbled->cdev.brightness_set = rb750_led_brightness_set;
  82                 rbled->cdev.brightness = LED_OFF;
  83
  84                 rbled->mask = led_data->mask;
  85                 rbled->active_low = !!led_data->active_low;
  86                 rbled->latch_change = pdata->latch_change;
  87
  88                 ret = led_classdev_register(&pdev->dev, &rbled->cdev);
  89                 if (ret)
  90                         goto err;
  91         }
  92
  93         platform_set_drvdata(pdev, drvdata);
  94         return 0;
  95
  96 err:
  97         for (i = i - 1; i >= 0; i--)
  98                 led_classdev_unregister(&drvdata->led_devs[i].cdev);
  99
 100         kfree(drvdata);
 101         return ret;
 102 }
 103
 104 static int rb750_led_remove(struct platform_device *pdev)
 105 {
 106         struct rb750_led_drvdata *drvdata;
 107         int i;
 108
 109         drvdata = platform_get_drvdata(pdev);
 110         for (i = 0; i < drvdata->num_leds; i++)
 111                 led_classdev_unregister(&drvdata->led_devs[i].cdev);
 112
 113         kfree(drvdata);
 114         return 0;
 115 }
 116
 117 static struct platform_driver rb750_led_driver = {
 118         .probe          = rb750_led_probe,
 119         .remove         = rb750_led_remove,
 120         .driver         = {
 121                 .name   = DRV_NAME,
 122                 .owner  = THIS_MODULE,
 123         },
 124 };
 125
 126 MODULE_ALIAS("platform:leds-rb750");
 127
 128 static int __init rb750_led_init(void)
 129 {
 130         return platform_driver_register(&rb750_led_driver);
 131 }
 132
 133 static void __exit rb750_led_exit(void)
 134 {
 135         platform_driver_unregister(&rb750_led_driver);
 136 }
 137
 138 module_init(rb750_led_init);
 139 module_exit(rb750_led_exit);
 140
 141 MODULE_DESCRIPTION(DRV_NAME);
 142 MODULE_DESCRIPTION("LED driver for the RouterBOARD 750");
 143 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 144 MODULE_LICENSE("GPL v2");