1 // SPDX-License-Identifier: GPL-2.0-or-later
3  *	Real Time Clock interface for Linux on Atmel AT91RM9200
7  *	Converted to RTC class model by Andrew Victor
10  *	Based on s3c2410-rtc.c Simtec Electronics
12  *	Based on sa1100-rtc.c by Nils Faerber
13  *	Based on rtc.c by Paul Gortmaker
27 #include <linux/rtc.h>
126 	 * Register read back (of any RTC-register) needed to make sure  in at91_rtc_write_idr()
127 	 * IDR-register write has reached the peripheral before updating  in at91_rtc_write_idr()
132 	 * way to be certain would be to poll the IMR-register, which is  in at91_rtc_write_idr()
146 	if (at91_rtc_config->use_shadow_imr) {  in at91_rtc_read_imr()
172 	tm->tm_sec  = bcd2bin(FIELD_GET(AT91_RTC_SEC, time));  in at91_rtc_decodetime()
173 	tm->tm_min  = bcd2bin(FIELD_GET(AT91_RTC_MIN, time));  in at91_rtc_decodetime()
174 	tm->tm_hour = bcd2bin(FIELD_GET(AT91_RTC_HOUR, time));  in at91_rtc_decodetime()
178 	 * the year - so these will return an invalid value.  in at91_rtc_decodetime()
180 	tm->tm_year  = bcd2bin(date & AT91_RTC_CENT) * 100;	/* century */  in at91_rtc_decodetime()
181 	tm->tm_year += bcd2bin(FIELD_GET(AT91_RTC_YEAR, date));	/* year */  in at91_rtc_decodetime()
183 	tm->tm_wday = bcd2bin(FIELD_GET(AT91_RTC_DAY, date)) - 1;	/* day of the week [0-6], Sunday=0 */  in at91_rtc_decodetime()
184 	tm->tm_mon  = bcd2bin(FIELD_GET(AT91_RTC_MONTH, date)) - 1;  in at91_rtc_decodetime()
185 	tm->tm_mday = bcd2bin(FIELD_GET(AT91_RTC_DATE, date));  in at91_rtc_decodetime()
189  * Read current time and date in RTC
194 	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);  in at91_rtc_readtime()
195 	tm->tm_year = tm->tm_year - 1900;  in at91_rtc_readtime()
203  * Set current time and date in RTC
222 			  FIELD_PREP(AT91_RTC_SEC, bin2bcd(tm->tm_sec))  in at91_rtc_settime()
223 			| FIELD_PREP(AT91_RTC_MIN, bin2bcd(tm->tm_min))  in at91_rtc_settime()
224 			| FIELD_PREP(AT91_RTC_HOUR, bin2bcd(tm->tm_hour)));  in at91_rtc_settime()
228 				     bin2bcd((tm->tm_year + 1900) / 100))  in at91_rtc_settime()
229 			| FIELD_PREP(AT91_RTC_YEAR, bin2bcd(tm->tm_year % 100))  in at91_rtc_settime()
230 			| FIELD_PREP(AT91_RTC_MONTH, bin2bcd(tm->tm_mon + 1))  in at91_rtc_settime()
231 			| FIELD_PREP(AT91_RTC_DAY, bin2bcd(tm->tm_wday + 1))  in at91_rtc_settime()
232 			| FIELD_PREP(AT91_RTC_DATE, bin2bcd(tm->tm_mday)));  in at91_rtc_settime()
244  * Read alarm time and date in RTC
248 	struct rtc_time *tm = &alrm->time;  in at91_rtc_readalarm()
251 	tm->tm_year = -1;  in at91_rtc_readalarm()
253 	alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)  in at91_rtc_readalarm()
257 		alrm->enabled ? "en" : "dis");  in at91_rtc_readalarm()
263  * Set alarm time and date in RTC
267 	struct rtc_time tm = alrm->time;  in at91_rtc_setalarm()
271 		  FIELD_PREP(AT91_RTC_SEC, bin2bcd(alrm->time.tm_sec))  in at91_rtc_setalarm()
272 		| FIELD_PREP(AT91_RTC_MIN, bin2bcd(alrm->time.tm_min))  in at91_rtc_setalarm()
273 		| FIELD_PREP(AT91_RTC_HOUR, bin2bcd(alrm->time.tm_hour))  in at91_rtc_setalarm()
276 		  FIELD_PREP(AT91_RTC_MONTH, bin2bcd(alrm->time.tm_mon + 1))  in at91_rtc_setalarm()
277 		| FIELD_PREP(AT91_RTC_DATE, bin2bcd(alrm->time.tm_mday))  in at91_rtc_setalarm()
280 	if (alrm->enabled) {  in at91_rtc_setalarm()
316 		val = -val;  in at91_rtc_readoffset()
332 		return -ERANGE;  in at91_rtc_setoffset()
333 	if (offset < -AT91_RTC_CORR_DIVIDEND / 2)  in at91_rtc_setoffset()
334 		return -ERANGE;  in at91_rtc_setoffset()
342 		offset = -offset;  in at91_rtc_setoffset()
365 	mr |= FIELD_PREP(AT91_RTC_CORRECTION, corr - 1);  in at91_rtc_setoffset()
373  * IRQ handler for the RTC
378 	struct rtc_device *rtc = platform_get_drvdata(pdev);  in at91_rtc_interrupt()  local
398 			rtc_update_irq(rtc, 1, events);  in at91_rtc_interrupt()
400 			dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n",  in at91_rtc_interrupt()
428 		.compatible = "atmel,at91rm9200-rtc",
431 		.compatible = "atmel,at91sam9x5-rtc",
434 		.compatible = "atmel,sama5d4-rtc",
437 		.compatible = "atmel,sama5d2-rtc",
440 		.compatible = "microchip,sam9x60-rtc",
467  * Initialize and install RTC driver
471 	struct rtc_device *rtc;  in at91_rtc_probe()  local
475 	at91_rtc_config = of_device_get_match_data(&pdev->dev);  in at91_rtc_probe()
477 		return -ENODEV;  in at91_rtc_probe()
481 		dev_err(&pdev->dev, "no mmio resource defined\n");  in at91_rtc_probe()
482 		return -ENXIO;  in at91_rtc_probe()
487 		return -ENXIO;  in at91_rtc_probe()
489 	at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,  in at91_rtc_probe()
492 		dev_err(&pdev->dev, "failed to map registers, aborting.\n");  in at91_rtc_probe()
493 		return -ENOMEM;  in at91_rtc_probe()
496 	rtc = devm_rtc_allocate_device(&pdev->dev);  in at91_rtc_probe()
497 	if (IS_ERR(rtc))  in at91_rtc_probe()
498 		return PTR_ERR(rtc);  in at91_rtc_probe()
499 	platform_set_drvdata(pdev, rtc);  in at91_rtc_probe()
501 	sclk = devm_clk_get(&pdev->dev, NULL);  in at91_rtc_probe()
507 		dev_err(&pdev->dev, "Could not enable slow clock\n");  in at91_rtc_probe()
519 	ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,  in at91_rtc_probe()
523 		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);  in at91_rtc_probe()
528 	 * being wake-capable; if it didn't, do that here.  in at91_rtc_probe()
530 	if (!device_can_wakeup(&pdev->dev))  in at91_rtc_probe()
531 		device_init_wakeup(&pdev->dev, 1);  in at91_rtc_probe()
533 	if (at91_rtc_config->has_correction)  in at91_rtc_probe()
534 		rtc->ops = &sama5d4_rtc_ops;  in at91_rtc_probe()
536 		rtc->ops = &at91_rtc_ops;  in at91_rtc_probe()
538 	rtc->range_min = RTC_TIMESTAMP_BEGIN_1900;  in at91_rtc_probe()
539 	rtc->range_max = RTC_TIMESTAMP_END_2099;  in at91_rtc_probe()
540 	ret = devm_rtc_register_device(rtc);  in at91_rtc_probe()
549 	dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");  in at91_rtc_probe()
559  * Disable and remove the RTC driver
581 /* AT91RM9200 RTC Power management control */
610 	struct rtc_device *rtc = dev_get_drvdata(dev);  in at91_rtc_resume()  local
619 				rtc_update_irq(rtc, 1, cached_events);  in at91_rtc_resume()
655 MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");