drivers/rtc/rtc-starfire.c

   1 /* rtc-starfire.c: Starfire platform RTC driver.
   2  *
   3  * Author: David S. Miller
   4  * License: GPL
   5  *
   6  * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/rtc.h>
  12 #include <linux/platform_device.h>
  13
  14 #include <asm/oplib.h>
  15
  16 static u32 starfire_get_time(void)
  17 {
  18         static char obp_gettod[32];
  19         static u32 unix_tod;
  20
  21         sprintf(obp_gettod, "h# %08x unix-gettod",
  22                 (unsigned int) (long) &unix_tod);
  23         prom_feval(obp_gettod);
  24
  25         return unix_tod;
  26 }
  27
  28 static int starfire_read_time(struct device *dev, struct rtc_time *tm)
  29 {
  30         rtc_time64_to_tm(starfire_get_time(), tm);
  31         return 0;
  32 }
  33
  34 static const struct rtc_class_ops starfire_rtc_ops = {
  35         .read_time      = starfire_read_time,
  36 };
  37
  38 static int __init starfire_rtc_probe(struct platform_device *pdev)
  39 {
  40         struct rtc_device *rtc;
  41
  42         rtc = devm_rtc_allocate_device(&pdev->dev);
  43         if (IS_ERR(rtc))
  44                 return PTR_ERR(rtc);
  45
  46         rtc->ops = &starfire_rtc_ops;
  47         rtc->range_max = U32_MAX;
  48
  49         platform_set_drvdata(pdev, rtc);
  50
  51         return devm_rtc_register_device(rtc);
  52 }
  53
  54 static struct platform_driver starfire_rtc_driver = {
  55         .driver         = {
  56                 .name   = "rtc-starfire",
  57         },
  58 };
  59
  60 builtin_platform_driver_probe(starfire_rtc_driver, starfire_rtc_probe);