1 // SPDX-License-Identifier: GPL-2.0-only
16  * Execute a function while the UIP (Update-in-progress) bit of the RTC is
17  * unset. The timeout is configurable by the caller in ms.
22 			int timeout,  in mc146818_avoid_UIP()  argument
29 	for (i = 0; UIP_RECHECK_LOOPS_MS(i) < timeout; i++) {  in mc146818_avoid_UIP()
34 		 * readout is unspecified. The maximum update time is ~2ms. Poll  in mc146818_avoid_UIP()
81 			pr_warn("Reading current time from RTC took around %li ms\n",  in mc146818_avoid_UIP()
91  * If the UIP (Update-in-progress) bit of the RTC is set for more then
92  * 10ms, the RTC is apparently broken or not present.
119 	 * by the RTC when initially set to a non-zero value.  in mc146818_get_time_callback()
121 	p->time->tm_sec = seconds;  in mc146818_get_time_callback()
122 	p->time->tm_min = CMOS_READ(RTC_MINUTES);  in mc146818_get_time_callback()
123 	p->time->tm_hour = CMOS_READ(RTC_HOURS);  in mc146818_get_time_callback()
124 	p->time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);  in mc146818_get_time_callback()
125 	p->time->tm_mon = CMOS_READ(RTC_MONTH);  in mc146818_get_time_callback()
126 	p->time->tm_year = CMOS_READ(RTC_YEAR);  in mc146818_get_time_callback()
128 	p->real_year = CMOS_READ(RTC_DEC_YEAR);  in mc146818_get_time_callback()
133 		p->century = CMOS_READ(acpi_gbl_FADT.century);  in mc146818_get_time_callback()
135 		p->century = 0;  in mc146818_get_time_callback()
139 	p->ctrl = CMOS_READ(RTC_CONTROL);  in mc146818_get_time_callback()
143  * mc146818_get_time - Get the current time from the RTC
145  * @timeout: timeout value in ms
148  * provided struct rtc_time. The timeout parameter specifies the maximum
151  * Return: 0 on success, -ETIMEDOUT if the RTC did not become ready within
152  * the specified timeout, or another error code if an error occurred.
154 int mc146818_get_time(struct rtc_time *time, int timeout)  in mc146818_get_time()  argument
160 	if (!mc146818_avoid_UIP(mc146818_get_time_callback, timeout, &p)) {  in mc146818_get_time()
162 		return -ETIMEDOUT;  in mc146818_get_time()
167 		time->tm_sec = bcd2bin(time->tm_sec);  in mc146818_get_time()
168 		time->tm_min = bcd2bin(time->tm_min);  in mc146818_get_time()
169 		time->tm_hour = bcd2bin(time->tm_hour);  in mc146818_get_time()
170 		time->tm_mday = bcd2bin(time->tm_mday);  in mc146818_get_time()
171 		time->tm_mon = bcd2bin(time->tm_mon);  in mc146818_get_time()
172 		time->tm_year = bcd2bin(time->tm_year);  in mc146818_get_time()
179 	time->tm_year += p.real_year - 72;  in mc146818_get_time()
184 		time->tm_year += (p.century - 19) * 100;  in mc146818_get_time()
191 	if (time->tm_year <= 69)  in mc146818_get_time()
192 		time->tm_year += 100;  in mc146818_get_time()
194 	time->tm_mon--;  in mc146818_get_time()
223 	yrs = time->tm_year;  in mc146818_set_time()
224 	mon = time->tm_mon + 1;   /* tm_mon starts at zero */  in mc146818_set_time()
225 	day = time->tm_mday;  in mc146818_set_time()
226 	hrs = time->tm_hour;  in mc146818_set_time()
227 	min = time->tm_min;  in mc146818_set_time()
228 	sec = time->tm_sec;  in mc146818_set_time()
231 		return -EINVAL;  in mc146818_set_time()
241 	 * for non-leap years, so that Feb, 29th is handled  in mc146818_set_time()
245 		real_yrs--;  in mc146818_set_time()
262 		return -EINVAL;  in mc146818_set_time()
265 		yrs -= 100;  in mc146818_set_time()