text: /* rtc-generic: RTC driver using the generic RTC abstraction
   *
   * Copyright (C) 2008 Kyle McMartin <kyle@mcmartin.ca>
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/time.h>
  #include <linux/platform_device.h>
  #include <linux/rtc.h>
  
  #include <asm/rtc.h>
  
  static int generic_get_time(struct device *dev, struct rtc_time *tm)
  {
  	unsigned int ret = get_rtc_time(tm);
  
  	if (ret & RTC_BATT_BAD)
  		return -EOPNOTSUPP;
  
  	return rtc_valid_tm(tm);
  }
  
  static int generic_set_time(struct device *dev, struct rtc_time *tm)
  {
  	if (set_rtc_time(tm) < 0)
  		return -EOPNOTSUPP;
  
  	return 0;
  }
  
  static const struct rtc_class_ops generic_rtc_ops = {
  	.read_time = generic_get_time,
  	.set_time = generic_set_time,
  };
  
  static int __init generic_rtc_probe(struct platform_device *dev)
  {
  	struct rtc_device *rtc;
  
  	rtc = devm_rtc_device_register(&dev->dev, "rtc-generic",
  					&generic_rtc_ops, THIS_MODULE);
  	if (IS_ERR(rtc))
  		return PTR_ERR(rtc);
  
  	platform_set_drvdata(dev, rtc);
  
  	return 0;
  }
  
  static int __exit generic_rtc_remove(struct platform_device *dev)
  {
  	return 0;
  }
  
  static struct platform_driver generic_rtc_driver = {
  	.driver = {
  		.name = "rtc-generic",
  		.owner = THIS_MODULE,
  	},
  	.remove = __exit_p(generic_rtc_remove),
  };
  
  module_platform_driver_probe(generic_rtc_driver, generic_rtc_probe);
  
  MODULE_AUTHOR("Kyle McMartin <kyle@mcmartin.ca>");
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Generic RTC driver");
  MODULE_ALIAS("platform:rtc-generic");
  