236 lines
5 KiB
C
236 lines
5 KiB
C
![]() |
/*
|
||
|
* rtc-efi: RTC Class Driver for EFI-based systems
|
||
|
*
|
||
|
* Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
|
||
|
*
|
||
|
* Author: dann frazier <dannf@hp.com>
|
||
|
* Based on efirtc.c by Stephane Eranian
|
||
|
*
|
||
|
* This program is free software; you can redistribute it and/or modify it
|
||
|
* under the terms of the GNU General Public License as published by the
|
||
|
* Free Software Foundation; either version 2 of the License, or (at your
|
||
|
* option) any later version.
|
||
|
*
|
||
|
*/
|
||
|
|
||
|
#include <linux/kernel.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/time.h>
|
||
|
#include <linux/platform_device.h>
|
||
|
#include <linux/rtc.h>
|
||
|
#include <linux/efi.h>
|
||
|
|
||
|
#define EFI_ISDST (EFI_TIME_ADJUST_DAYLIGHT|EFI_TIME_IN_DAYLIGHT)
|
||
|
/*
|
||
|
* EFI Epoch is 1/1/1998
|
||
|
*/
|
||
|
#define EFI_RTC_EPOCH 1998
|
||
|
|
||
|
/*
|
||
|
* returns day of the year [0-365]
|
||
|
*/
|
||
|
static inline int
|
||
|
compute_yday(efi_time_t *eft)
|
||
|
{
|
||
|
/* efi_time_t.month is in the [1-12] so, we need -1 */
|
||
|
return rtc_year_days(eft->day - 1, eft->month - 1, eft->year);
|
||
|
}
|
||
|
/*
|
||
|
* returns day of the week [0-6] 0=Sunday
|
||
|
*
|
||
|
* Don't try to provide a year that's before 1998, please !
|
||
|
*/
|
||
|
static int
|
||
|
compute_wday(efi_time_t *eft)
|
||
|
{
|
||
|
int y;
|
||
|
int ndays = 0;
|
||
|
|
||
|
if (eft->year < 1998) {
|
||
|
printk(KERN_ERR "efirtc: EFI year < 1998, invalid date\n");
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
for (y = EFI_RTC_EPOCH; y < eft->year; y++)
|
||
|
ndays += 365 + (is_leap_year(y) ? 1 : 0);
|
||
|
|
||
|
ndays += compute_yday(eft);
|
||
|
|
||
|
/*
|
||
|
* 4=1/1/1998 was a Thursday
|
||
|
*/
|
||
|
return (ndays + 4) % 7;
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
convert_to_efi_time(struct rtc_time *wtime, efi_time_t *eft)
|
||
|
{
|
||
|
eft->year = wtime->tm_year + 1900;
|
||
|
eft->month = wtime->tm_mon + 1;
|
||
|
eft->day = wtime->tm_mday;
|
||
|
eft->hour = wtime->tm_hour;
|
||
|
eft->minute = wtime->tm_min;
|
||
|
eft->second = wtime->tm_sec;
|
||
|
eft->nanosecond = 0;
|
||
|
eft->daylight = wtime->tm_isdst ? EFI_ISDST : 0;
|
||
|
eft->timezone = EFI_UNSPECIFIED_TIMEZONE;
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
convert_from_efi_time(efi_time_t *eft, struct rtc_time *wtime)
|
||
|
{
|
||
|
memset(wtime, 0, sizeof(*wtime));
|
||
|
wtime->tm_sec = eft->second;
|
||
|
wtime->tm_min = eft->minute;
|
||
|
wtime->tm_hour = eft->hour;
|
||
|
wtime->tm_mday = eft->day;
|
||
|
wtime->tm_mon = eft->month - 1;
|
||
|
wtime->tm_year = eft->year - 1900;
|
||
|
|
||
|
/* day of the week [0-6], Sunday=0 */
|
||
|
wtime->tm_wday = compute_wday(eft);
|
||
|
|
||
|
/* day in the year [1-365]*/
|
||
|
wtime->tm_yday = compute_yday(eft);
|
||
|
|
||
|
|
||
|
switch (eft->daylight & EFI_ISDST) {
|
||
|
case EFI_ISDST:
|
||
|
wtime->tm_isdst = 1;
|
||
|
break;
|
||
|
case EFI_TIME_ADJUST_DAYLIGHT:
|
||
|
wtime->tm_isdst = 0;
|
||
|
break;
|
||
|
default:
|
||
|
wtime->tm_isdst = -1;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static int efi_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
|
||
|
{
|
||
|
efi_time_t eft;
|
||
|
efi_status_t status;
|
||
|
|
||
|
/*
|
||
|
* As of EFI v1.10, this call always returns an unsupported status
|
||
|
*/
|
||
|
status = efi.get_wakeup_time((efi_bool_t *)&wkalrm->enabled,
|
||
|
(efi_bool_t *)&wkalrm->pending, &eft);
|
||
|
|
||
|
if (status != EFI_SUCCESS)
|
||
|
return -EINVAL;
|
||
|
|
||
|
convert_from_efi_time(&eft, &wkalrm->time);
|
||
|
|
||
|
return rtc_valid_tm(&wkalrm->time);
|
||
|
}
|
||
|
|
||
|
static int efi_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
|
||
|
{
|
||
|
efi_time_t eft;
|
||
|
efi_status_t status;
|
||
|
|
||
|
convert_to_efi_time(&wkalrm->time, &eft);
|
||
|
|
||
|
/*
|
||
|
* XXX Fixme:
|
||
|
* As of EFI 0.92 with the firmware I have on my
|
||
|
* machine this call does not seem to work quite
|
||
|
* right
|
||
|
*
|
||
|
* As of v1.10, this call always returns an unsupported status
|
||
|
*/
|
||
|
status = efi.set_wakeup_time((efi_bool_t)wkalrm->enabled, &eft);
|
||
|
|
||
|
printk(KERN_WARNING "write status is %d\n", (int)status);
|
||
|
|
||
|
return status == EFI_SUCCESS ? 0 : -EINVAL;
|
||
|
}
|
||
|
|
||
|
static int efi_read_time(struct device *dev, struct rtc_time *tm)
|
||
|
{
|
||
|
efi_status_t status;
|
||
|
efi_time_t eft;
|
||
|
efi_time_cap_t cap;
|
||
|
|
||
|
status = efi.get_time(&eft, &cap);
|
||
|
|
||
|
if (status != EFI_SUCCESS) {
|
||
|
/* should never happen */
|
||
|
printk(KERN_ERR "efitime: can't read time\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
convert_from_efi_time(&eft, tm);
|
||
|
|
||
|
return rtc_valid_tm(tm);
|
||
|
}
|
||
|
|
||
|
static int efi_set_time(struct device *dev, struct rtc_time *tm)
|
||
|
{
|
||
|
efi_status_t status;
|
||
|
efi_time_t eft;
|
||
|
|
||
|
convert_to_efi_time(tm, &eft);
|
||
|
|
||
|
status = efi.set_time(&eft);
|
||
|
|
||
|
return status == EFI_SUCCESS ? 0 : -EINVAL;
|
||
|
}
|
||
|
|
||
|
static const struct rtc_class_ops efi_rtc_ops = {
|
||
|
.read_time = efi_read_time,
|
||
|
.set_time = efi_set_time,
|
||
|
.read_alarm = efi_read_alarm,
|
||
|
.set_alarm = efi_set_alarm,
|
||
|
};
|
||
|
|
||
|
static int __init efi_rtc_probe(struct platform_device *dev)
|
||
|
{
|
||
|
struct rtc_device *rtc;
|
||
|
|
||
|
rtc = rtc_device_register("rtc-efi", &dev->dev, &efi_rtc_ops,
|
||
|
THIS_MODULE);
|
||
|
if (IS_ERR(rtc))
|
||
|
return PTR_ERR(rtc);
|
||
|
|
||
|
platform_set_drvdata(dev, rtc);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int __exit efi_rtc_remove(struct platform_device *dev)
|
||
|
{
|
||
|
struct rtc_device *rtc = platform_get_drvdata(dev);
|
||
|
|
||
|
rtc_device_unregister(rtc);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct platform_driver efi_rtc_driver = {
|
||
|
.driver = {
|
||
|
.name = "rtc-efi",
|
||
|
.owner = THIS_MODULE,
|
||
|
},
|
||
|
.probe = efi_rtc_probe,
|
||
|
.remove = __exit_p(efi_rtc_remove),
|
||
|
};
|
||
|
|
||
|
static int __init efi_rtc_init(void)
|
||
|
{
|
||
|
return platform_driver_probe(&efi_rtc_driver, efi_rtc_probe);
|
||
|
}
|
||
|
|
||
|
static void __exit efi_rtc_exit(void)
|
||
|
{
|
||
|
platform_driver_unregister(&efi_rtc_driver);
|
||
|
}
|
||
|
|
||
|
module_init(efi_rtc_init);
|
||
|
module_exit(efi_rtc_exit);
|
||
|
|
||
|
MODULE_AUTHOR("dann frazier <dannf@hp.com>");
|
||
|
MODULE_LICENSE("GPL");
|
||
|
MODULE_DESCRIPTION("EFI RTC driver");
|