xref: /linux/drivers/rtc/rtc-starfire.c (revision 163b099146b85d1b05bd2eaa045acbeee25c29e4)
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);
61