1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * rtc-efi: RTC Class Driver for EFI-based systems
5  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
24  * returns day of the year [0-365]
29 	/* efi_time_t.month is in the [1-12] so, we need -1 */  in compute_yday()
30 	return rtc_year_days(eft->day, eft->month - 1, eft->year);  in compute_yday()
34  * returns day of the week [0-6] 0=Sunday
39 	int ndays = eft->year * (365 % 7)  in compute_wday()
40 		    + (eft->year - 1) / 4  in compute_wday()
41 		    - (eft->year - 1) / 100  in compute_wday()
42 		    + (eft->year - 1) / 400  in compute_wday()
55 	eft->year	= wtime->tm_year + 1900;  in convert_to_efi_time()
56 	eft->month	= wtime->tm_mon + 1;  in convert_to_efi_time()
57 	eft->day	= wtime->tm_mday;  in convert_to_efi_time()
58 	eft->hour	= wtime->tm_hour;  in convert_to_efi_time()
59 	eft->minute	= wtime->tm_min;  in convert_to_efi_time()
60 	eft->second	= wtime->tm_sec;  in convert_to_efi_time()
61 	eft->nanosecond = 0;  in convert_to_efi_time()
62 	eft->daylight	= wtime->tm_isdst ? EFI_ISDST : 0;  in convert_to_efi_time()
63 	eft->timezone	= EFI_UNSPECIFIED_TIMEZONE;  in convert_to_efi_time()
71 	if (eft->second >= 60)  in convert_from_efi_time()
73 	wtime->tm_sec  = eft->second;  in convert_from_efi_time()
75 	if (eft->minute >= 60)  in convert_from_efi_time()
77 	wtime->tm_min  = eft->minute;  in convert_from_efi_time()
79 	if (eft->hour >= 24)  in convert_from_efi_time()
81 	wtime->tm_hour = eft->hour;  in convert_from_efi_time()
83 	if (!eft->day || eft->day > 31)  in convert_from_efi_time()
85 	wtime->tm_mday = eft->day;  in convert_from_efi_time()
87 	if (!eft->month || eft->month > 12)  in convert_from_efi_time()
89 	wtime->tm_mon  = eft->month - 1;  in convert_from_efi_time()
91 	if (eft->year < 1900 || eft->year > 9999)  in convert_from_efi_time()
93 	wtime->tm_year = eft->year - 1900;  in convert_from_efi_time()
95 	/* day in the year [1-365]*/  in convert_from_efi_time()
96 	wtime->tm_yday = compute_yday(eft);  in convert_from_efi_time()
98 	/* day of the week [0-6], Sunday=0 */  in convert_from_efi_time()
99 	wtime->tm_wday = compute_wday(eft, wtime->tm_yday);  in convert_from_efi_time()
101 	switch (eft->daylight & EFI_ISDST) {  in convert_from_efi_time()
103 		wtime->tm_isdst = 1;  in convert_from_efi_time()
106 		wtime->tm_isdst = 0;  in convert_from_efi_time()
109 		wtime->tm_isdst = -1;  in convert_from_efi_time()
119 	efi_time_cap_t cap;  in efi_read_time()  local
121 	status = efi.get_time(&eft, &cap);  in efi_read_time()
126 		return -EINVAL;  in efi_read_time()
130 		return -EIO;  in efi_read_time()
144 	return status == EFI_SUCCESS ? 0 : -EINVAL;  in efi_set_time()
150 	efi_time_cap_t    cap;  in efi_procfs()  local
153 	memset(&cap, 0, sizeof(cap));  in efi_procfs()
155 	efi.get_time(&eft, &cap);  in efi_procfs()
159 		   "Date\t\t: %u-%u-%u\n"  in efi_procfs()
178 		   cap.resolution, cap.accuracy, cap.sets_to_zero);  in efi_procfs()
193 	efi_time_cap_t cap;  in efi_rtc_probe()  local
196 	if (efi.get_time(&eft, &cap) != EFI_SUCCESS)  in efi_rtc_probe()
197 		return -ENODEV;  in efi_rtc_probe()
199 	rtc = devm_rtc_allocate_device(&dev->dev);  in efi_rtc_probe()
205 	rtc->ops = &efi_rtc_ops;  in efi_rtc_probe()
206 	clear_bit(RTC_FEATURE_ALARM, rtc->features);  in efi_rtc_probe()
208 	device_init_wakeup(&dev->dev, true);  in efi_rtc_probe()
215 		.name = "rtc-efi",
224 MODULE_ALIAS("platform:rtc-efi");