drivers/rtc/rtc-generic.c

   1 /* rtc-generic: RTC driver using the generic RTC abstraction
   2  *
   3  * Copyright (C) 2008 Kyle McMartin <kyle@mcmartin.ca>
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/module.h>
   8 #include <linux/time.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/rtc.h>
  11
  12 #if defined(CONFIG_M68K) || defined(CONFIG_PARISC) || \
  13     defined(CONFIG_PPC) || defined(CONFIG_SUPERH32)
  14 #include <asm/rtc.h>
  15
  16 static int generic_get_time(struct device *dev, struct rtc_time *tm)
  17 {
  18         unsigned int ret = get_rtc_time(tm);
  19
  20         if (ret & RTC_BATT_BAD)
  21                 return -EOPNOTSUPP;
  22
  23         return rtc_valid_tm(tm);
  24 }
  25
  26 static int generic_set_time(struct device *dev, struct rtc_time *tm)
  27 {
  28         if (set_rtc_time(tm) < 0)
  29                 return -EOPNOTSUPP;
  30
  31         return 0;
  32 }
  33
  34 static const struct rtc_class_ops generic_rtc_ops = {
  35         .read_time = generic_get_time,
  36         .set_time = generic_set_time,
  37 };
  38 #else
  39 #define generic_rtc_ops *(struct rtc_class_ops*)NULL
  40 #endif
  41
  42 static int __init generic_rtc_probe(struct platform_device *dev)
  43 {
  44         struct rtc_device *rtc;
  45         const struct rtc_class_ops *ops;
  46
  47         ops = dev_get_platdata(&dev->dev);
  48         if (!ops)
  49                 ops = &generic_rtc_ops;
  50
  51         rtc = devm_rtc_device_register(&dev->dev, "rtc-generic",
  52                                         ops, THIS_MODULE);
  53         if (IS_ERR(rtc))
  54                 return PTR_ERR(rtc);
  55
  56         platform_set_drvdata(dev, rtc);
  57
  58         return 0;
  59 }
  60
  61 static struct platform_driver generic_rtc_driver = {
  62         .driver = {
  63                 .name = "rtc-generic",
  64         },
  65 };
  66
  67 module_platform_driver_probe(generic_rtc_driver, generic_rtc_probe);
  68
  69 MODULE_AUTHOR("Kyle McMartin <kyle@mcmartin.ca>");
  70 MODULE_LICENSE("GPL");
  71 MODULE_DESCRIPTION("Generic RTC driver");
  72 MODULE_ALIAS("platform:rtc-generic");