1 /* rtc-sun4v.c: Hypervisor based RTC for SUN4V systems.
3 * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/rtc.h>
13 #include <linux/platform_device.h>
15 #include <asm/hypervisor.h>
17 static unsigned long hypervisor_get_time(void)
19 unsigned long ret, time;
23 ret = sun4v_tod_get(&time);
26 if (ret == HV_EWOULDBLOCK) {
31 pr_warn("tod_get() timed out.\n");
34 pr_warn("tod_get() not supported.\n");
38 static int sun4v_read_time(struct device *dev, struct rtc_time *tm)
40 rtc_time_to_tm(hypervisor_get_time(), tm);
44 static int hypervisor_set_time(unsigned long secs)
50 ret = sun4v_tod_set(secs);
53 if (ret == HV_EWOULDBLOCK) {
58 pr_warn("tod_set() timed out.\n");
61 pr_warn("tod_set() not supported.\n");
65 static int sun4v_set_time(struct device *dev, struct rtc_time *tm)
70 err = rtc_tm_to_time(tm, &secs);
74 return hypervisor_set_time(secs);
77 static const struct rtc_class_ops sun4v_rtc_ops = {
78 .read_time = sun4v_read_time,
79 .set_time = sun4v_set_time,
82 static int __init sun4v_rtc_probe(struct platform_device *pdev)
84 struct rtc_device *rtc = rtc_device_register("sun4v", &pdev->dev,
85 &sun4v_rtc_ops, THIS_MODULE);
89 platform_set_drvdata(pdev, rtc);
93 static int __exit sun4v_rtc_remove(struct platform_device *pdev)
95 struct rtc_device *rtc = platform_get_drvdata(pdev);
97 rtc_device_unregister(rtc);
101 static struct platform_driver sun4v_rtc_driver = {
104 .owner = THIS_MODULE,
106 .remove = __exit_p(sun4v_rtc_remove),
109 module_platform_driver_probe(sun4v_rtc_driver, sun4v_rtc_probe);
111 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
112 MODULE_DESCRIPTION("SUN4V RTC driver");
113 MODULE_LICENSE("GPL");