Merge branch 'next' into for-linus

Prepare input updates for 5.17 merge window.

34 files changed, 518 insertions, 598 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index d8c13fded164..e1bc5214494e 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -75,6 +75,15 @@ config RTC_DEBUG
 	  Say yes here to enable debugging support in the RTC framework
 	  and individual RTC drivers.
 
+config RTC_LIB_KUNIT_TEST
+	tristate "KUnit test for RTC lib functions" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  Enable this option to test RTC library functions.
+
+	  If unsure, say N.
+
 config RTC_NVMEM
 	bool "RTC non volatile storage support"
 	select NVMEM
@@ -501,11 +510,11 @@ config RTC_DRV_M41T80_WDT
 	  watchdog timer in the ST M41T60 and M41T80 RTC chips series.
 
 config RTC_DRV_BD70528
-	tristate "ROHM BD70528, BD71815 and BD71828 PMIC RTC"
-	depends on MFD_ROHM_BD71828 || MFD_ROHM_BD70528 && (BD70528_WATCHDOG || !BD70528_WATCHDOG)
+	tristate "ROHM BD71815 and BD71828 PMIC RTC"
+	depends on MFD_ROHM_BD71828
 	help
 	  If you say Y here you will get support for the RTC
-	  block on ROHM BD70528, BD71815 and BD71828 Power Management IC.
+	  block on ROHM BD71815 and BD71828 Power Management IC.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-bd70528.
@@ -624,6 +633,7 @@ config RTC_DRV_FM3130
 
 config RTC_DRV_RX8010
 	tristate "Epson RX8010SJ"
+	select REGMAP_I2C
 	help
 	  If you say yes here you get support for the Epson RX8010SJ RTC
 	  chip.
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 2dd0dd956b0e..5ceeafe4d5b2 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -15,6 +15,8 @@ rtc-core-$(CONFIG_RTC_INTF_DEV)		+= dev.o
 rtc-core-$(CONFIG_RTC_INTF_PROC)	+= proc.o
 rtc-core-$(CONFIG_RTC_INTF_SYSFS)	+= sysfs.o
 
+obj-$(CONFIG_RTC_LIB_KUNIT_TEST)	+= lib_test.o
+
 # Keep the list ordered.
 
 obj-$(CONFIG_RTC_DRV_88PM80X)	+= rtc-88pm80x.o
diff --git a/drivers/rtc/lib.c b/drivers/rtc/lib.c
index 23284580df97..fe361652727a 100644
--- a/drivers/rtc/lib.c
+++ b/drivers/rtc/lib.c
@@ -6,6 +6,8 @@
  * Author: Alessandro Zummo <a.zummo@towertech.it>
  *
  * based on arch/arm/common/rtctime.c and other bits
+ *
+ * Author: Cassio Neri <cassio.neri@gmail.com> (rtc_time64_to_tm)
  */
 
 #include <linux/export.h>
@@ -22,8 +24,6 @@ static const unsigned short rtc_ydays[2][13] = {
 	{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
 };
 
-#define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400)
-
 /*
  * The number of days in the month.
  */
@@ -42,42 +42,95 @@ int rtc_year_days(unsigned int day, unsigned int month, unsigned int year)
 }
 EXPORT_SYMBOL(rtc_year_days);
 
-/*
- * rtc_time64_to_tm - Converts time64_t to rtc_time.
- * Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
+/**
+ * rtc_time64_to_tm - converts time64_t to rtc_time.
+ *
+ * @time:	The number of seconds since 01-01-1970 00:00:00.
+ *		(Must be positive.)
+ * @tm:		Pointer to the struct rtc_time.
  */
 void rtc_time64_to_tm(time64_t time, struct rtc_time *tm)
 {
-	unsigned int month, year, secs;
+	unsigned int secs;
 	int days;
 
+	u64 u64tmp;
+	u32 u32tmp, udays, century, day_of_century, year_of_century, year,
+		day_of_year, month, day;
+	bool is_Jan_or_Feb, is_leap_year;
+
 	/* time must be positive */
 	days = div_s64_rem(time, 86400, &secs);
 
 	/* day of the week, 1970-01-01 was a Thursday */
 	tm->tm_wday = (days + 4) % 7;
 
-	year = 1970 + days / 365;
-	days -= (year - 1970) * 365
-		+ LEAPS_THRU_END_OF(year - 1)
-		- LEAPS_THRU_END_OF(1970 - 1);
-	while (days < 0) {
-		year -= 1;
-		days += 365 + is_leap_year(year);
-	}
-	tm->tm_year = year - 1900;
-	tm->tm_yday = days + 1;
-
-	for (month = 0; month < 11; month++) {
-		int newdays;
-
-		newdays = days - rtc_month_days(month, year);
-		if (newdays < 0)
-			break;
-		days = newdays;
-	}
-	tm->tm_mon = month;
-	tm->tm_mday = days + 1;
+	/*
+	 * The following algorithm is, basically, Proposition 6.3 of Neri
+	 * and Schneider [1]. In a few words: it works on the computational
+	 * (fictitious) calendar where the year starts in March, month = 2
+	 * (*), and finishes in February, month = 13. This calendar is
+	 * mathematically convenient because the day of the year does not
+	 * depend on whether the year is leap or not. For instance:
+	 *
+	 * March 1st		0-th day of the year;
+	 * ...
+	 * April 1st		31-st day of the year;
+	 * ...
+	 * January 1st		306-th day of the year; (Important!)
+	 * ...
+	 * February 28th	364-th day of the year;
+	 * February 29th	365-th day of the year (if it exists).
+	 *
+	 * After having worked out the date in the computational calendar
+	 * (using just arithmetics) it's easy to convert it to the
+	 * corresponding date in the Gregorian calendar.
+	 *
+	 * [1] "Euclidean Affine Functions and Applications to Calendar
+	 * Algorithms". https://arxiv.org/abs/2102.06959
+	 *
+	 * (*) The numbering of months follows rtc_time more closely and
+	 * thus, is slightly different from [1].
+	 */
+
+	udays		= ((u32) days) + 719468;
+
+	u32tmp		= 4 * udays + 3;
+	century		= u32tmp / 146097;
+	day_of_century	= u32tmp % 146097 / 4;
+
+	u32tmp		= 4 * day_of_century + 3;
+	u64tmp		= 2939745ULL * u32tmp;
+	year_of_century	= upper_32_bits(u64tmp);
+	day_of_year	= lower_32_bits(u64tmp) / 2939745 / 4;
+
+	year		= 100 * century + year_of_century;
+	is_leap_year	= year_of_century != 0 ?
+		year_of_century % 4 == 0 : century % 4 == 0;
+
+	u32tmp		= 2141 * day_of_year + 132377;
+	month		= u32tmp >> 16;
+	day		= ((u16) u32tmp) / 2141;
+
+	/*
+	 * Recall that January 01 is the 306-th day of the year in the
+	 * computational (not Gregorian) calendar.
+	 */
+	is_Jan_or_Feb	= day_of_year >= 306;
+
+	/* Converts to the Gregorian calendar. */
+	year		= year + is_Jan_or_Feb;
+	month		= is_Jan_or_Feb ? month - 12 : month;
+	day		= day + 1;
+
+	day_of_year	= is_Jan_or_Feb ?
+		day_of_year - 306 : day_of_year + 31 + 28 + is_leap_year;
+
+	/* Converts to rtc_time's format. */
+	tm->tm_year	= (int) (year - 1900);
+	tm->tm_mon	= (int) month;
+	tm->tm_mday	= (int) day;
+	tm->tm_yday	= (int) day_of_year + 1;
 
 	tm->tm_hour = secs / 3600;
 	secs -= tm->tm_hour * 3600;
diff --git a/drivers/rtc/lib_test.c b/drivers/rtc/lib_test.c
new file mode 100644
index 000000000000..d5caf36c56cd
--- /dev/null
+++ b/drivers/rtc/lib_test.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: LGPL-2.1+
+
+#include <kunit/test.h>
+#include <linux/rtc.h>
+
+/*
+ * Advance a date by one day.
+ */
+static void advance_date(int *year, int *month, int *mday, int *yday)
+{
+	if (*mday != rtc_month_days(*month - 1, *year)) {
+		++*mday;
+		++*yday;
+		return;
+	}
+
+	*mday = 1;
+	if (*month != 12) {
+		++*month;
+		++*yday;
+		return;
+	}
+
+	*month = 1;
+	*yday  = 1;
+	++*year;
+}
+
+/*
+ * Checks every day in a 160000 years interval starting on 1970-01-01
+ * against the expected result.
+ */
+static void rtc_time64_to_tm_test_date_range(struct kunit *test)
+{
+	/*
+	 * 160000 years	= (160000 / 400) * 400 years
+	 *		= (160000 / 400) * 146097 days
+	 *		= (160000 / 400) * 146097 * 86400 seconds
+	 */
+	time64_t total_secs = ((time64_t) 160000) / 400 * 146097 * 86400;
+
+	int year	= 1970;
+	int month	= 1;
+	int mday	= 1;
+	int yday	= 1;
+
+	struct rtc_time result;
+	time64_t secs;
+	s64 days;
+
+	for (secs = 0; secs <= total_secs; secs += 86400) {
+
+		rtc_time64_to_tm(secs, &result);
+
+		days = div_s64(secs, 86400);
+
+		#define FAIL_MSG "%d/%02d/%02d (%2d) : %ld", \
+			year, month, mday, yday, days
+
+		KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG);
+		KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG);
+		KUNIT_ASSERT_EQ_MSG(test, mday, result.tm_mday, FAIL_MSG);
+		KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG);
+
+		advance_date(&year, &month, &mday, &yday);
+	}
+}
+
+static struct kunit_case rtc_lib_test_cases[] = {
+	KUNIT_CASE(rtc_time64_to_tm_test_date_range),
+	{}
+};
+
+static struct kunit_suite rtc_lib_test_suite = {
+	.name = "rtc_lib_test_cases",
+	.test_cases = rtc_lib_test_cases,
+};
+
+kunit_test_suite(rtc_lib_test_suite);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/rtc/proc.c b/drivers/rtc/proc.c
index 73344598fc1b..cbcdbb19d848 100644
--- a/drivers/rtc/proc.c
+++ b/drivers/rtc/proc.c
@@ -23,8 +23,8 @@ static bool is_rtc_hctosys(struct rtc_device *rtc)
 	int size;
 	char name[NAME_SIZE];
 
-	size = scnprintf(name, NAME_SIZE, "rtc%d", rtc->id);
-	if (size > NAME_SIZE)
+	size = snprintf(name, NAME_SIZE, "rtc%d", rtc->id);
+	if (size >= NAME_SIZE)
 		return false;
 
 	return !strncmp(name, CONFIG_RTC_HCTOSYS_DEVICE, NAME_SIZE);
diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c
index 2216be429ab7..b7b5ea1a4e67 100644
--- a/drivers/rtc/rtc-at91sam9.c
+++ b/drivers/rtc/rtc-at91sam9.c
@@ -184,7 +184,7 @@ static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
 		return -EILSEQ;
 
 	memset(alrm, 0, sizeof(*alrm));
-	if (alarm != ALARM_DISABLED && offset != 0) {
+	if (alarm != ALARM_DISABLED) {
 		rtc_time64_to_tm(offset + alarm, tm);
 
 		dev_dbg(dev, "%s: %ptR\n", __func__, tm);
diff --git a/drivers/rtc/rtc-au1xxx.c b/drivers/rtc/rtc-au1xxx.c
index e6428b27b5d4..630ea5de6871 100644
--- a/drivers/rtc/rtc-au1xxx.c
+++ b/drivers/rtc/rtc-au1xxx.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Au1xxx counter0 (aka Time-Of-Year counter) RTC interface driver.
  *
  * Copyright (C) 2008 Manuel Lauss <mano@roarinelk.homelinux.net>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
  */
 
 /* All current Au1xxx SoCs have 2 counters fed by an external 32.768 kHz
diff --git a/drivers/rtc/rtc-bd70528.c b/drivers/rtc/rtc-bd70528.c
index 6454afca02a6..59b627fc1ecf 100644
--- a/drivers/rtc/rtc-bd70528.c
+++ b/drivers/rtc/rtc-bd70528.c
@@ -2,10 +2,9 @@
 //
 // Copyright (C) 2018 ROHM Semiconductors
 //
-// RTC driver for ROHM BD70528 PMIC
+// RTC driver for ROHM BD71828 and BD71815 PMIC
 
 #include <linux/bcd.h>
-#include <linux/mfd/rohm-bd70528.h>
 #include <linux/mfd/rohm-bd71815.h>
 #include <linux/mfd/rohm-bd71828.h>
 #include <linux/module.h>
@@ -39,11 +38,6 @@ struct bd70528_rtc_data {
 	u8 year;
 } __packed;
 
-struct bd70528_rtc_wake {
-	struct bd70528_rtc_day time;
-	u8 ctrl;
-} __packed;
-
 struct bd71828_rtc_alm {
 	struct bd70528_rtc_data alm0;
 	struct bd70528_rtc_data alm1;
@@ -51,141 +45,14 @@ struct bd71828_rtc_alm {
 	u8 alm1_mask;
 } __packed;
 
-struct bd70528_rtc_alm {
-	struct bd70528_rtc_data data;
-	u8 alm_mask;
-	u8 alm_repeat;
-} __packed;
-
 struct bd70528_rtc {
 	struct rohm_regmap_dev *parent;
 	struct regmap *regmap;
 	struct device *dev;
 	u8 reg_time_start;
 	u8 bd718xx_alm_block_start;
-	bool has_rtc_timers;
 };
 
-static int bd70528_set_wake(struct rohm_regmap_dev *bd70528,
-			    int enable, int *old_state)
-{
-	int ret;
-	unsigned int ctrl_reg;
-
-	ret = regmap_read(bd70528->regmap, BD70528_REG_WAKE_EN, &ctrl_reg);
-	if (ret)
-		return ret;
-
-	if (old_state) {
-		if (ctrl_reg & BD70528_MASK_WAKE_EN)
-			*old_state |= BD70528_WAKE_STATE_BIT;
-		else
-			*old_state &= ~BD70528_WAKE_STATE_BIT;
-
-		if (!enable == !(*old_state & BD70528_WAKE_STATE_BIT))
-			return 0;
-	}
-
-	if (enable)
-		ctrl_reg |= BD70528_MASK_WAKE_EN;
-	else
-		ctrl_reg &= ~BD70528_MASK_WAKE_EN;
-
-	return regmap_write(bd70528->regmap, BD70528_REG_WAKE_EN,
-			    ctrl_reg);
-}
-
-static int bd70528_set_elapsed_tmr(struct rohm_regmap_dev *bd70528,
-				   int enable, int *old_state)
-{
-	int ret;
-	unsigned int ctrl_reg;
-
-	/*
-	 * TBD
-	 * What is the purpose of elapsed timer ?
-	 * Is the timeout registers counting down, or is the disable - re-enable
-	 * going to restart the elapsed-time counting? If counting is restarted
-	 * the timeout should be decreased by the amount of time that has
-	 * elapsed since starting the timer. Maybe we should store the monotonic
-	 * clock value when timer is started so that if RTC is set while timer
-	 * is armed we could do the compensation. This is a hack if RTC/system
-	 * clk are drifting. OTOH, RTC controlled via I2C is in any case
-	 * inaccurate...
-	 */
-	ret = regmap_read(bd70528->regmap, BD70528_REG_ELAPSED_TIMER_EN,
-			  &ctrl_reg);
-	if (ret)
-		return ret;
-
-	if (old_state) {
-		if (ctrl_reg & BD70528_MASK_ELAPSED_TIMER_EN)
-			*old_state |= BD70528_ELAPSED_STATE_BIT;
-		else
-			*old_state &= ~BD70528_ELAPSED_STATE_BIT;
-
-		if ((!enable) == (!(*old_state & BD70528_ELAPSED_STATE_BIT)))
-			return 0;
-	}
-
-	if (enable)
-		ctrl_reg |= BD70528_MASK_ELAPSED_TIMER_EN;
-	else
-		ctrl_reg &= ~BD70528_MASK_ELAPSED_TIMER_EN;
-
-	return regmap_write(bd70528->regmap, BD70528_REG_ELAPSED_TIMER_EN,
-			    ctrl_reg);
-}
-
-static int bd70528_set_rtc_based_timers(struct bd70528_rtc *r, int new_state,
-					int *old_state)
-{
-	int ret;
-
-	ret = bd70528_wdt_set(r->parent, new_state & BD70528_WDT_STATE_BIT,
-			      old_state);
-	if (ret) {
-		dev_err(r->dev,
-			"Failed to disable WDG for RTC setting (%d)\n", ret);
-		return ret;
-	}
-	ret = bd70528_set_elapsed_tmr(r->parent,
-				      new_state & BD70528_ELAPSED_STATE_BIT,
-				      old_state);
-	if (ret) {
-		dev_err(r->dev,
-			"Failed to disable 'elapsed timer' for RTC setting\n");
-		return ret;
-	}
-	ret = bd70528_set_wake(r->parent, new_state & BD70528_WAKE_STATE_BIT,
-			       old_state);
-	if (ret) {
-		dev_err(r->dev,
-			"Failed to disable 'wake timer' for RTC setting\n");
-		return ret;
-	}
-
-	return ret;
-}
-
-static int bd70528_re_enable_rtc_based_timers(struct bd70528_rtc *r,
-					      int old_state)
-{
-	if (!r->has_rtc_timers)
-		return 0;
-
-	return bd70528_set_rtc_based_timers(r, old_state, NULL);
-}
-
-static int bd70528_disable_rtc_based_timers(struct bd70528_rtc *r,
-					    int *old_state)
-{
-	if (!r->has_rtc_timers)
-		return 0;
-
-	return bd70528_set_rtc_based_timers(r, 0, old_state);
-}
-
 static inline void tmday2rtc(struct rtc_time *t, struct bd70528_rtc_day *d)
 {
 	d->sec &= ~BD70528_MASK_RTC_SEC;
@@ -267,52 +134,6 @@ static int bd71828_set_alarm(struct device *dev, struct rtc_wkalrm *a)
 
 }
 
-static int bd70528_set_alarm(struct device *dev, struct rtc_wkalrm *a)
-{
-	struct bd70528_rtc_wake wake;
-	struct bd70528_rtc_alm alm;
-	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
-
-	ret = regmap_bulk_read(r->regmap, BD70528_REG_RTC_WAKE_START, &wake,
-			       sizeof(wake));
-	if (ret) {
-		dev_err(dev, "Failed to read wake regs\n");
-		return ret;
-	}
-
-	ret = regmap_bulk_read(r->regmap, BD70528_REG_RTC_ALM_START, &alm,
-			       sizeof(alm));
-	if (ret) {
-		dev_err(dev, "Failed to read alarm regs\n");
-		return ret;
-	}
-
-	tm2rtc(&a->time, &alm.data);
-	tmday2rtc(&a->time, &wake.time);
-
-	if (a->enabled) {
-		alm.alm_mask &= ~BD70528_MASK_ALM_EN;
-		wake.ctrl |= BD70528_MASK_WAKE_EN;
-	} else {
-		alm.alm_mask |= BD70528_MASK_ALM_EN;
-		wake.ctrl &= ~BD70528_MASK_WAKE_EN;
-	}
-
-	ret = regmap_bulk_write(r->regmap, BD70528_REG_RTC_WAKE_START, &wake,
-				sizeof(wake));
-	if (ret) {
-		dev_err(dev, "Failed to set wake time\n");
-		return ret;
-	}
-	ret = regmap_bulk_write(r->regmap, BD70528_REG_RTC_ALM_START, &alm,
-				sizeof(alm));
-	if (ret)
-		dev_err(dev, "Failed to set alarm time\n");
-
-	return ret;
-}
-
 static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a)
 {
 	int ret;
@@ -336,78 +157,28 @@ static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a)
 	return 0;
 }
 
-static int bd70528_read_alarm(struct device *dev, struct rtc_wkalrm *a)
+static int bd71828_set_time(struct device *dev, struct rtc_time *t)
 {
-	struct bd70528_rtc_alm alm;
 	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
-
-	ret = regmap_bulk_read(r->regmap, BD70528_REG_RTC_ALM_START, &alm,
-			       sizeof(alm));
-	if (ret) {
-		dev_err(dev, "Failed to read alarm regs\n");
-		return ret;
-	}
-
-	rtc2tm(&alm.data, &a->time);
-	a->time.tm_mday = -1;
-	a->time.tm_mon = -1;
-	a->time.tm_year = -1;
-	a->enabled = !(alm.alm_mask & BD70528_MASK_ALM_EN);
-	a->pending = 0;
-
-	return 0;
-}
-
-static int bd70528_set_time_locked(struct device *dev, struct rtc_time *t)
-{
-	int ret, tmpret, old_states;
 	struct bd70528_rtc_data rtc_data;
 	struct bd70528_rtc *r = dev_get_drvdata(dev);
 
-	ret = bd70528_disable_rtc_based_timers(r, &old_states);
-	if (ret)
-		return ret;
-
-	tmpret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,
-				  sizeof(rtc_data));
-	if (tmpret) {
+	ret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,
+			       sizeof(rtc_data));
+	if (ret) {
 		dev_err(dev, "Failed to read RTC time registers\n");
-		goto renable_out;
+		return ret;
 	}
 	tm2rtc(t, &rtc_data);
 
-	tmpret = regmap_bulk_write(r->regmap, r->reg_time_start, &rtc_data,
-				   sizeof(rtc_data));
-	if (tmpret) {
+	ret = regmap_bulk_write(r->regmap, r->reg_time_start, &rtc_data,
+				sizeof(rtc_data));
+	if (ret)
 		dev_err(dev, "Failed to set RTC time\n");
-		goto renable_out;
-	}
-
-renable_out:
-	ret = bd70528_re_enable_rtc_based_timers(r, old_states);
-	if (tmpret)
-		ret = tmpret;
 
 	return ret;
 }
 
-static int bd71828_set_time(struct device *dev, struct rtc_time *t)
-{
-	return bd70528_set_time_locked(dev, t);
-}
-
-static int bd70528_set_time(struct device *dev, struct rtc_time *t)
-{
-	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
-
-	bd70528_wdt_lock(r->parent);
-	ret = bd70528_set_time_locked(dev, t);
-	bd70528_wdt_unlock(r->parent);
-	return ret;
-}
-
 static int bd70528_get_time(struct device *dev, struct rtc_time *t)
 {
 	struct bd70528_rtc *r = dev_get_drvdata(dev);
@@ -427,31 +198,6 @@ static int bd70528_get_time(struct device *dev, struct rtc_time *t)
 	return 0;
 }
 
-static int bd70528_alm_enable(struct device *dev, unsigned int enabled)
-{
-	int ret;
-	unsigned int enableval = BD70528_MASK_ALM_EN;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
-
-	if (enabled)
-		enableval = 0;
-
-	bd70528_wdt_lock(r->parent);
-	ret = bd70528_set_wake(r->parent, enabled, NULL);
-	if (ret) {
-		dev_err(dev, "Failed to change wake state\n");
-		goto out_unlock;
-	}
-	ret = regmap_update_bits(r->regmap, BD70528_REG_RTC_ALM_MASK,
-				 BD70528_MASK_ALM_EN, enableval);
-	if (ret)
-		dev_err(dev, "Failed to change alarm state\n");
-
-out_unlock:
-	bd70528_wdt_unlock(r->parent);
-	return ret;
-}
-
 static int bd71828_alm_enable(struct device *dev, unsigned int enabled)
 {
 	int ret;
@@ -470,14 +216,6 @@ static int bd71828_alm_enable(struct device *dev, unsigned int enabled)
 	return ret;
 }
 
-static const struct rtc_class_ops bd70528_rtc_ops = {
-	.read_time		= bd70528_get_time,
-	.set_time		= bd70528_set_time,
-	.read_alarm		= bd70528_read_alarm,
-	.set_alarm		= bd70528_set_alarm,
-	.alarm_irq_enable	= bd70528_alm_enable,
-};
-
 static const struct rtc_class_ops bd71828_rtc_ops = {
 	.read_time		= bd70528_get_time,
 	.set_time		= bd71828_set_time,
@@ -503,7 +241,6 @@ static int bd70528_probe(struct platform_device *pdev)
 	struct rtc_device *rtc;
 	int irq;
 	unsigned int hr;
-	bool enable_main_irq = false;
 	u8 hour_reg;
 	enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
 
@@ -518,21 +255,9 @@ static int bd70528_probe(struct platform_device *pdev)
 	}
 
 	bd_rtc->dev = &pdev->dev;
+	rtc_ops = &bd71828_rtc_ops;
 
 	switch (chip) {
-	case ROHM_CHIP_TYPE_BD70528:
-		bd_rtc->parent = dev_get_drvdata(pdev->dev.parent);
-		if (!bd_rtc->parent) {
-			dev_err(&pdev->dev, "No MFD data\n");
-			return -EINVAL;
-		}
-		irq_name = "bd70528-rtc-alm";
-		bd_rtc->has_rtc_timers = true;
-		bd_rtc->reg_time_start = BD70528_REG_RTC_START;
-		hour_reg = BD70528_REG_RTC_HOUR;
-		enable_main_irq = true;
-		rtc_ops = &bd70528_rtc_ops;
-		break;
 	case ROHM_CHIP_TYPE_BD71815:
 		irq_name = "bd71815-rtc-alm-0";
 		bd_rtc->reg_time_start = BD71815_REG_RTC_START;
@@ -549,14 +274,12 @@ static int bd70528_probe(struct platform_device *pdev)
 		 */
 		bd_rtc->bd718xx_alm_block_start = BD71815_REG_RTC_ALM_START;
 		hour_reg = BD71815_REG_HOUR;
-		rtc_ops = &bd71828_rtc_ops;
 		break;
 	case ROHM_CHIP_TYPE_BD71828:
 		irq_name = "bd71828-rtc-alm-0";
 		bd_rtc->reg_time_start = BD71828_REG_RTC_START;
 		bd_rtc->bd718xx_alm_block_start = BD71828_REG_RTC_ALM_START;
 		hour_reg = BD71828_REG_RTC_HOUR;
-		rtc_ops = &bd71828_rtc_ops;
 		break;
 	default:
 		dev_err(&pdev->dev, "Unknown chip\n");
@@ -611,27 +334,10 @@ static int bd70528_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	/*
-	 *  BD70528 irq controller is not touching the main mask register.
-	 *  So enable the RTC block interrupts at main level. We can just
-	 *  leave them enabled as irq-controller should disable irqs
-	 *  from sub-registers when IRQ is disabled or freed.
-	 */
-	if (enable_main_irq) {
-		ret = regmap_update_bits(bd_rtc->regmap,
-				 BD70528_REG_INT_MAIN_MASK,
-				 BD70528_INT_RTC_MASK, 0);
-		if (ret) {
-			dev_err(&pdev->dev, "Failed to enable RTC interrupts\n");
-			return ret;
-		}
-	}
-
 	return devm_rtc_register_device(rtc);
 }
 
 static const struct platform_device_id bd718x7_rtc_id[] = {
-	{ "bd70528-rtc", ROHM_CHIP_TYPE_BD70528 },
 	{ "bd71828-rtc", ROHM_CHIP_TYPE_BD71828 },
 	{ "bd71815-rtc", ROHM_CHIP_TYPE_BD71815 },
 	{ },
@@ -649,6 +355,6 @@ static struct platform_driver bd70528_rtc = {
 module_platform_driver(bd70528_rtc);
 
 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
-MODULE_DESCRIPTION("ROHM BD70528 and BD71828 PMIC RTC driver");
+MODULE_DESCRIPTION("ROHM BD71828 and BD71815 PMIC RTC driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:bd70528-rtc");
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 670fd8a2970e..4eb53412b808 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -229,19 +229,13 @@ static int cmos_read_time(struct device *dev, struct rtc_time *t)
 	if (!pm_trace_rtc_valid())
 		return -EIO;
 
-	/* REVISIT:  if the clock has a "century" register, use
-	 * that instead of the heuristic in mc146818_get_time().
-	 * That'll make Y3K compatility (year > 2070) easy!
-	 */
 	mc146818_get_time(t);
 	return 0;
 }
 
 static int cmos_set_time(struct device *dev, struct rtc_time *t)
 {
-	/* REVISIT:  set the "century" register if available
-	 *
-	 * NOTE: this ignores the issue whereby updating the seconds
+	/* NOTE: this ignores the issue whereby updating the seconds
 	 * takes effect exactly 500ms after we write the register.
 	 * (Also queueing and other delays before we get this far.)
 	 */
@@ -1053,7 +1047,9 @@ static void cmos_check_wkalrm(struct device *dev)
 	 * ACK the rtc irq here
 	 */
 	if (t_now >= cmos->alarm_expires && cmos_use_acpi_alarm()) {
+		local_irq_disable();
 		cmos_interrupt(0, (void *)cmos->rtc);
+		local_irq_enable();
 		return;
 	}
 
diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c
index fab79921a712..8db5a631bca8 100644
--- a/drivers/rtc/rtc-ds1374.c
+++ b/drivers/rtc/rtc-ds1374.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * RTC client/driver for the Maxim/Dallas DS1374 Real-Time Clock over I2C
  *
@@ -6,11 +7,7 @@
  *
  * Copyright (C) 2014 Rose Technology
  * Copyright (C) 2006-2007 Freescale Semiconductor
- *
- * 2005 (c) MontaVista Software, Inc. This file is licensed under
- * the terms of the GNU General Public License version 2. This program
- * is licensed "as is" without any warranty of any kind, whether express
- * or implied.
+ * Copyright (c) 2005 MontaVista Software, Inc.
  */
 /*
  * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
diff --git a/drivers/rtc/rtc-efi.c b/drivers/rtc/rtc-efi.c
index edb64debd173..138c5e0046c8 100644
--- a/drivers/rtc/rtc-efi.c
+++ b/drivers/rtc/rtc-efi.c
@@ -280,7 +280,6 @@ static struct platform_driver efi_rtc_driver = {
 
 module_platform_driver_probe(efi_rtc_driver, efi_rtc_probe);
 
-MODULE_ALIAS("platform:rtc-efi");
 MODULE_AUTHOR("dann frazier <dannf@dannf.org>");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("EFI RTC driver");
diff --git a/drivers/rtc/rtc-hid-sensor-time.c b/drivers/rtc/rtc-hid-sensor-time.c
index 47cd12db2356..16fdefafec5d 100644
--- a/drivers/rtc/rtc-hid-sensor-time.c
+++ b/drivers/rtc/rtc-hid-sensor-time.c
@@ -328,3 +328,4 @@ module_platform_driver(hid_time_platform_driver);
 MODULE_DESCRIPTION("HID Sensor Time");
 MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_HID);
diff --git a/drivers/rtc/rtc-imxdi.c b/drivers/rtc/rtc-imxdi.c
index c1806f4d68e7..4b712e5ab08a 100644
--- a/drivers/rtc/rtc-imxdi.c
+++ b/drivers/rtc/rtc-imxdi.c
@@ -24,6 +24,7 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/rtc.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
@@ -811,6 +812,9 @@ static int __init dryice_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, imxdi);
 
+	device_init_wakeup(&pdev->dev, true);
+	dev_pm_set_wake_irq(&pdev->dev, norm_irq);
+
 	imxdi->rtc->ops = &dryice_rtc_ops;
 	imxdi->rtc->range_max = U32_MAX;
 
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index 89128fc29ccc..f736f8c22e96 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -544,10 +544,22 @@ static struct clk *m41t80_sqw_register_clk(struct m41t80_data *m41t80)
 {
 	struct i2c_client *client = m41t80->client;
 	struct device_node *node = client->dev.of_node;
+	struct device_node *fixed_clock;
 	struct clk *clk;
 	struct clk_init_data init;
 	int ret;
 
+	fixed_clock = of_get_child_by_name(node, "clock");
+	if (fixed_clock) {
+		/*
+		 * skip registering square wave clock when a fixed
+		 * clock has been registered. The fixed clock is
+		 * registered automatically when being referenced.
+		 */
+		of_node_put(fixed_clock);
+		return 0;
+	}
+
 	/* First disable the clock */
 	ret = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
 	if (ret < 0)
@@ -599,10 +611,8 @@ static unsigned long wdt_is_open;
 static int boot_flag;
 
 /**
- *	wdt_ping:
- *
- *	Reload counter one with the watchdog timeout. We don't bother reloading
- *	the cascade counter.
+ *	wdt_ping - Reload counter one with the watchdog timeout.
+ *	We don't bother reloading the cascade counter.
  */
 static void wdt_ping(void)
 {
@@ -638,9 +648,7 @@ static void wdt_ping(void)
 }
 
 /**
- *	wdt_disable:
- *
- *	disables watchdog.
+ *	wdt_disable - disables watchdog.
  */
 static void wdt_disable(void)
 {
@@ -677,7 +685,7 @@ static void wdt_disable(void)
 }
 
 /**
- *	wdt_write:
+ *	wdt_write - write to watchdog.
  *	@file: file handle to the watchdog
  *	@buf: buffer to write (unused as data does not matter here
  *	@count: count of bytes
@@ -703,7 +711,7 @@ static ssize_t wdt_read(struct file *file, char __user *buf,
 }
 
 /**
- *	wdt_ioctl:
+ *	wdt_ioctl - ioctl handler to set watchdog.
  *	@file: file handle to the device
  *	@cmd: watchdog command
  *	@arg: argument pointer
@@ -778,7 +786,7 @@ static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
 }
 
 /**
- *	wdt_open:
+ *	wdt_open - open a watchdog.
  *	@inode: inode of device
  *	@file: file handle to device
  *
@@ -802,7 +810,7 @@ static int wdt_open(struct inode *inode, struct file *file)
 }
 
 /**
- *	wdt_close:
+ *	wdt_release - release a watchdog.
  *	@inode: inode to board
  *	@file: file handle to board
  *
@@ -815,7 +823,7 @@ static int wdt_release(struct inode *inode, struct file *file)
 }
 
 /**
- *	notify_sys:
+ *	wdt_notify_sys - notify to watchdog.
  *	@this: our notifier block
  *	@code: the event being reported
  *	@unused: unused
diff --git a/drivers/rtc/rtc-max6900.c b/drivers/rtc/rtc-max6900.c
index ab60f13fa3ef..4beadfa41644 100644
--- a/drivers/rtc/rtc-max6900.c
+++ b/drivers/rtc/rtc-max6900.c
@@ -1,14 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * rtc class driver for the Maxim MAX6900 chip
  *
+ * Copyright (c) 2007 MontaVista, Software, Inc.
+ *
  * Author: Dale Farnsworth <dale@farnsworth.org>
  *
  * based on previously existing rtc class drivers
- *
- * 2007 (c) MontaVista, Software, Inc.  This file is licensed under
- * the terms of the GNU General Public License version 2.  This program
- * is licensed "as is" without any warranty of any kind, whether express
- * or implied.
  */
 
 #include <linux/module.h>
diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
index d51cc12114cb..eae7cb9faf1e 100644
--- a/drivers/rtc/rtc-max77686.c
+++ b/drivers/rtc/rtc-max77686.c
@@ -717,8 +717,8 @@ static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
 
 add_rtc_irq:
 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
-				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
-				  IRQF_SHARED, 0, info->drv_data->rtc_irq_chip,
+				  IRQF_ONESHOT | IRQF_SHARED,
+				  0, info->drv_data->rtc_irq_chip,
 				  &info->rtc_irq_data);
 	if (ret < 0) {
 		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c
index 6655035e5164..80dc479a6ff0 100644
--- a/drivers/rtc/rtc-mt6397.c
+++ b/drivers/rtc/rtc-mt6397.c
@@ -75,7 +75,7 @@ static int __mtk_rtc_read_time(struct mt6397_rtc *rtc,
 	tm->tm_min = data[RTC_OFFSET_MIN];
 	tm->tm_hour = data[RTC_OFFSET_HOUR];
 	tm->tm_mday = data[RTC_OFFSET_DOM];
-	tm->tm_mon = data[RTC_OFFSET_MTH];
+	tm->tm_mon = data[RTC_OFFSET_MTH] & RTC_TC_MTH_MASK;
 	tm->tm_year = data[RTC_OFFSET_YEAR];
 
 	ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC, sec);
diff --git a/drivers/rtc/rtc-mxc_v2.c b/drivers/rtc/rtc-mxc_v2.c
index a577a74aaf75..5e0383401629 100644
--- a/drivers/rtc/rtc-mxc_v2.c
+++ b/drivers/rtc/rtc-mxc_v2.c
@@ -372,6 +372,7 @@ static const struct of_device_id mxc_ids[] = {
 	{ .compatible = "fsl,imx53-rtc", },
 	{}
 };
+MODULE_DEVICE_TABLE(of, mxc_ids);
 
 static struct platform_driver mxc_rtc_driver = {
 	.driver = {
diff --git a/drivers/rtc/rtc-palmas.c b/drivers/rtc/rtc-palmas.c
index 4bcfb88674d3..67571f7f0bbc 100644
--- a/drivers/rtc/rtc-palmas.c
+++ b/drivers/rtc/rtc-palmas.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * rtc-palmas.c -- Palmas Real Time Clock driver.
 
@@ -7,20 +8,6 @@
  * Copyright (c) 2012, NVIDIA Corporation.
  *
  * Author: Laxman Dewangan <ldewangan@nvidia.com>
- *
- * 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 version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
- * whether express or implied; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- * 02111-1307, USA
  */
 
 #include <linux/bcd.h>
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index d13c20a2adf7..56c58b055dff 100644
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -10,7 +10,7 @@
  *
  * based on the other drivers in this same directory.
  *
- * Datasheet: http://cache.nxp.com/documents/data_sheet/PCF2127.pdf
+ * Datasheet: https://www.nxp.com/docs/en/data-sheet/PCF2127.pdf
  */
 
 #include <linux/i2c.h>
@@ -94,10 +94,20 @@
 #define PCF2127_WD_VAL_MAX		255
 #define PCF2127_WD_VAL_DEFAULT		60
 
+/* Mask for currently enabled interrupts */
+#define PCF2127_CTRL1_IRQ_MASK (PCF2127_BIT_CTRL1_TSF1)
+#define PCF2127_CTRL2_IRQ_MASK ( \
+		PCF2127_BIT_CTRL2_AF | \
+		PCF2127_BIT_CTRL2_WDTF | \
+		PCF2127_BIT_CTRL2_TSF2)
+
 struct pcf2127 {
 	struct rtc_device *rtc;
 	struct watchdog_device wdd;
 	struct regmap *regmap;
+	time64_t ts;
+	bool ts_valid;
+	bool irq_enabled;
 };
 
 /*
@@ -434,23 +444,96 @@ static int pcf2127_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	return pcf2127_rtc_alarm_irq_enable(dev, alrm->enabled);
 }
 
+/*
+ * This function reads ctrl2 register, caller is responsible for calling
+ * pcf2127_wdt_active_ping()
+ */
+static int pcf2127_rtc_ts_read(struct device *dev, time64_t *ts)
+{
+	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
+	struct rtc_time tm;
+	int ret;
+	unsigned char data[25];
+
+	ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL1, data,
+			       sizeof(data));
+	if (ret) {
+		dev_err(dev, "%s: read error ret=%d\n", __func__, ret);
+		return ret;
+	}
+
+	dev_dbg(dev,
+		"%s: raw data is cr1=%02x, cr2=%02x, cr3=%02x, ts_sc=%02x, ts_mn=%02x, ts_hr=%02x, ts_dm=%02x, ts_mo=%02x, ts_yr=%02x\n",
+		__func__, data[PCF2127_REG_CTRL1], data[PCF2127_REG_CTRL2],
+		data[PCF2127_REG_CTRL3], data[PCF2127_REG_TS_SC],
+		data[PCF2127_REG_TS_MN], data[PCF2127_REG_TS_HR],
+		data[PCF2127_REG_TS_DM], data[PCF2127_REG_TS_MO],
+		data[PCF2127_REG_TS_YR]);
+
+	tm.tm_sec = bcd2bin(data[PCF2127_REG_TS_SC] & 0x7F);
+	tm.tm_min = bcd2bin(data[PCF2127_REG_TS_MN] & 0x7F);
+	tm.tm_hour = bcd2bin(data[PCF2127_REG_TS_HR] & 0x3F);
+	tm.tm_mday = bcd2bin(data[PCF2127_REG_TS_DM] & 0x3F);
+	/* TS_MO register (month) value range: 1-12 */
+	tm.tm_mon = bcd2bin(data[PCF2127_REG_TS_MO] & 0x1F) - 1;
+	tm.tm_year = bcd2bin(data[PCF2127_REG_TS_YR]);
+	if (tm.tm_year < 70)
+		tm.tm_year += 100; /* assume we are in 1970...2069 */
+
+	ret = rtc_valid_tm(&tm);
+	if (ret) {
+		dev_err(dev, "Invalid timestamp. ret=%d\n", ret);
+		return ret;
+	}
+
+	*ts = rtc_tm_to_time64(&tm);
+	return 0;
+};
+
+static void pcf2127_rtc_ts_snapshot(struct device *dev)
+{
+	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
+	int ret;
+
+	/* Let userspace read the first timestamp */
+	if (pcf2127->ts_valid)
+		return;
+
+	ret = pcf2127_rtc_ts_read(dev, &pcf2127->ts);
+	if (!ret)
+		pcf2127->ts_valid = true;
+}
+
 static irqreturn_t pcf2127_rtc_irq(int irq, void *dev)
 {
 	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
-	unsigned int ctrl2 = 0;
+	unsigned int ctrl1, ctrl2;
 	int ret = 0;
 
+	ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL1, &ctrl1);
+	if (ret)
+		return IRQ_NONE;
+
 	ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);
 	if (ret)
 		return IRQ_NONE;
 
-	if (!(ctrl2 & PCF2127_BIT_CTRL2_AF))
+	if (!(ctrl1 & PCF2127_CTRL1_IRQ_MASK || ctrl2 & PCF2127_CTRL2_IRQ_MASK))
 		return IRQ_NONE;
 
-	regmap_write(pcf2127->regmap, PCF2127_REG_CTRL2,
-		     ctrl2 & ~(PCF2127_BIT_CTRL2_AF | PCF2127_BIT_CTRL2_WDTF));
+	if (ctrl1 & PCF2127_BIT_CTRL1_TSF1 || ctrl2 & PCF2127_BIT_CTRL2_TSF2)
+		pcf2127_rtc_ts_snapshot(dev);
+
+	if (ctrl1 & PCF2127_CTRL1_IRQ_MASK)
+		regmap_write(pcf2127->regmap, PCF2127_REG_CTRL1,
+			ctrl1 & ~PCF2127_CTRL1_IRQ_MASK);
+
+	if (ctrl2 & PCF2127_CTRL2_IRQ_MASK)
+		regmap_write(pcf2127->regmap, PCF2127_REG_CTRL2,
+			ctrl2 & ~PCF2127_CTRL2_IRQ_MASK);
 
-	rtc_update_irq(pcf2127->rtc, 1, RTC_IRQF | RTC_AF);
+	if (ctrl2 & PCF2127_BIT_CTRL2_AF)
+		rtc_update_irq(pcf2127->rtc, 1, RTC_IRQF | RTC_AF);
 
 	pcf2127_wdt_active_ping(&pcf2127->wdd);
 
@@ -475,23 +558,27 @@ static ssize_t timestamp0_store(struct device *dev,
 	struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent);
 	int ret;
 
-	ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL1,
-				 PCF2127_BIT_CTRL1_TSF1, 0);
-	if (ret) {
-		dev_err(dev, "%s: update ctrl1 ret=%d\n", __func__, ret);
-		return ret;
-	}
+	if (pcf2127->irq_enabled) {
+		pcf2127->ts_valid = false;
+	} else {
+		ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL1,
+			PCF2127_BIT_CTRL1_TSF1, 0);
+		if (ret) {
+			dev_err(dev, "%s: update ctrl1 ret=%d\n", __func__, ret);
+			return ret;
+		}
 
-	ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,
-				 PCF2127_BIT_CTRL2_TSF2, 0);
-	if (ret) {
-		dev_err(dev, "%s: update ctrl2 ret=%d\n", __func__, ret);
-		return ret;
-	}
+		ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,
+			PCF2127_BIT_CTRL2_TSF2, 0);
+		if (ret) {
+			dev_err(dev, "%s: update ctrl2 ret=%d\n", __func__, ret);
+			return ret;
+		}
 
-	ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
-	if (ret)
-		return ret;
+		ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
+		if (ret)
+			return ret;
+	}
 
 	return count;
 };
@@ -500,50 +587,36 @@ static ssize_t timestamp0_show(struct device *dev,
 			       struct device_attribute *attr, char *buf)
 {
 	struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent);
-	struct rtc_time tm;
+	unsigned int ctrl1, ctrl2;
 	int ret;
-	unsigned char data[25];
-
-	ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL1, data,
-			       sizeof(data));
-	if (ret) {
-		dev_err(dev, "%s: read error ret=%d\n", __func__, ret);
-		return ret;
-	}
-
-	dev_dbg(dev,
-		"%s: raw data is cr1=%02x, cr2=%02x, cr3=%02x, ts_sc=%02x, "
-		"ts_mn=%02x, ts_hr=%02x, ts_dm=%02x, ts_mo=%02x, ts_yr=%02x\n",
-		__func__, data[PCF2127_REG_CTRL1], data[PCF2127_REG_CTRL2],
-		data[PCF2127_REG_CTRL3], data[PCF2127_REG_TS_SC],
-		data[PCF2127_REG_TS_MN], data[PCF2127_REG_TS_HR],
-		data[PCF2127_REG_TS_DM], data[PCF2127_REG_TS_MO],
-		data[PCF2127_REG_TS_YR]);
+	time64_t ts;
+
+	if (pcf2127->irq_enabled) {
+		if (!pcf2127->ts_valid)
+			return 0;
+		ts = pcf2127->ts;
+	} else {
+		ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL1, &ctrl1);
+		if (ret)
+			return 0;
 
-	ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
-	if (ret)
-		return ret;
+		ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);
+		if (ret)
+			return 0;
 
-	if (!(data[PCF2127_REG_CTRL1] & PCF2127_BIT_CTRL1_TSF1) &&
-	    !(data[PCF2127_REG_CTRL2] & PCF2127_BIT_CTRL2_TSF2))
-		return 0;
+		if (!(ctrl1 & PCF2127_BIT_CTRL1_TSF1) &&
+		    !(ctrl2 & PCF2127_BIT_CTRL2_TSF2))
+			return 0;
 
-	tm.tm_sec = bcd2bin(data[PCF2127_REG_TS_SC] & 0x7F);
-	tm.tm_min = bcd2bin(data[PCF2127_REG_TS_MN] & 0x7F);
-	tm.tm_hour = bcd2bin(data[PCF2127_REG_TS_HR] & 0x3F);
-	tm.tm_mday = bcd2bin(data[PCF2127_REG_TS_DM] & 0x3F);
-	/* TS_MO register (month) value range: 1-12 */
-	tm.tm_mon = bcd2bin(data[PCF2127_REG_TS_MO] & 0x1F) - 1;
-	tm.tm_year = bcd2bin(data[PCF2127_REG_TS_YR]);
-	if (tm.tm_year < 70)
-		tm.tm_year += 100; /* assume we are in 1970...2069 */
-
-	ret = rtc_valid_tm(&tm);
-	if (ret)
-		return ret;
+		ret = pcf2127_rtc_ts_read(dev->parent, &ts);
+		if (ret)
+			return 0;
 
-	return sprintf(buf, "%llu\n",
-		       (unsigned long long)rtc_tm_to_time64(&tm));
+		ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
+		if (ret)
+			return ret;
+	}
+	return sprintf(buf, "%llu\n", (unsigned long long)ts);
 };
 
 static DEVICE_ATTR_RW(timestamp0);
@@ -594,6 +667,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
 			dev_err(dev, "failed to request alarm irq\n");
 			return ret;
 		}
+		pcf2127->irq_enabled = true;
 	}
 
 	if (alarm_irq > 0 || device_property_read_bool(dev, "wakeup-source")) {
diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c
index 82becae14229..14da4ab30104 100644
--- a/drivers/rtc/rtc-pcf85063.c
+++ b/drivers/rtc/rtc-pcf85063.c
@@ -21,10 +21,10 @@
 /*
  * Information for this driver was pulled from the following datasheets.
  *
- *  https://www.nxp.com/documents/data_sheet/PCF85063A.pdf
- *  https://www.nxp.com/documents/data_sheet/PCF85063TP.pdf
+ *  https://www.nxp.com/docs/en/data-sheet/PCF85063A.pdf
+ *  https://www.nxp.com/docs/en/data-sheet/PCF85063TP.pdf
  *
- *  PCF85063A -- Rev. 6 — 18 November 2015
+ *  PCF85063A -- Rev. 7 — 30 March 2018
  *  PCF85063TP -- Rev. 4 — 6 May 2015
  *
  *  https://www.microcrystal.com/fileadmin/Media/Products/RTC/App.Manual/RV-8263-C7_App-Manual.pdf
diff --git a/drivers/rtc/rtc-pcf8523.c b/drivers/rtc/rtc-pcf8523.c
index 740e2136ca98..8b6fb20774bf 100644
--- a/drivers/rtc/rtc-pcf8523.c
+++ b/drivers/rtc/rtc-pcf8523.c
@@ -10,41 +10,41 @@
 #include <linux/of.h>
 #include <linux/pm_wakeirq.h>
 
-#define REG_CONTROL1 0x00
-#define REG_CONTROL1_CAP_SEL BIT(7)
-#define REG_CONTROL1_STOP    BIT(5)
-#define REG_CONTROL1_AIE    BIT(1)
-
-#define REG_CONTROL2 0x01
-#define REG_CONTROL2_AF BIT(3)
-
-#define REG_CONTROL3 0x02
-#define REG_CONTROL3_PM_BLD BIT(7) /* battery low detection disabled */
-#define REG_CONTROL3_PM_VDD BIT(6) /* switch-over disabled */
-#define REG_CONTROL3_PM_DSM BIT(5) /* direct switching mode */
-#define REG_CONTROL3_PM_MASK 0xe0
-#define REG_CONTROL3_BLF BIT(2) /* battery low bit, read-only */
-
-#define REG_SECONDS  0x03
-#define REG_SECONDS_OS BIT(7)
-
-#define REG_MINUTES  0x04
-#define REG_HOURS    0x05
-#define REG_DAYS     0x06
-#define REG_WEEKDAYS 0x07
-#define REG_MONTHS   0x08
-#define REG_YEARS    0x09
-
-#define REG_MINUTE_ALARM	0x0a
-#define REG_HOUR_ALARM		0x0b
-#define REG_DAY_ALARM		0x0c
-#define REG_WEEKDAY_ALARM	0x0d
+#define PCF8523_REG_CONTROL1 0x00
+#define PCF8523_CONTROL1_CAP_SEL BIT(7)
+#define PCF8523_CONTROL1_STOP    BIT(5)
+#define PCF8523_CONTROL1_AIE    BIT(1)
+
+#define PCF8523_REG_CONTROL2 0x01
+#define PCF8523_CONTROL2_AF BIT(3)
+
+#define PCF8523_REG_CONTROL3 0x02
+#define PCF8523_CONTROL3_PM_BLD BIT(7) /* battery low detection disabled */
+#define PCF8523_CONTROL3_PM_VDD BIT(6) /* switch-over disabled */
+#define PCF8523_CONTROL3_PM_DSM BIT(5) /* direct switching mode */
+#define PCF8523_CONTROL3_PM_MASK 0xe0
+#define PCF8523_CONTROL3_BLF BIT(2) /* battery low bit, read-only */
+
+#define PCF8523_REG_SECONDS  0x03
+#define PCF8523_SECONDS_OS BIT(7)
+
+#define PCF8523_REG_MINUTES  0x04
+#define PCF8523_REG_HOURS    0x05
+#define PCF8523_REG_DAYS     0x06
+#define PCF8523_REG_WEEKDAYS 0x07
+#define PCF8523_REG_MONTHS   0x08
+#define PCF8523_REG_YEARS    0x09
+
+#define PCF8523_REG_MINUTE_ALARM	0x0a
+#define PCF8523_REG_HOUR_ALARM		0x0b
+#define PCF8523_REG_DAY_ALARM		0x0c
+#define PCF8523_REG_WEEKDAY_ALARM	0x0d
 #define ALARM_DIS BIT(7)
 
-#define REG_OFFSET   0x0e
-#define REG_OFFSET_MODE BIT(7)
+#define PCF8523_REG_OFFSET   0x0e
+#define PCF8523_OFFSET_MODE BIT(7)
 
-#define REG_TMR_CLKOUT_CTRL 0x0f
+#define PCF8523_TMR_CLKOUT_CTRL 0x0f
 
 struct pcf8523 {
 	struct rtc_device *rtc;
@@ -99,11 +99,11 @@ static int pcf8523_voltage_low(struct i2c_client *client)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL3, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL3, &value);
 	if (err < 0)
 		return err;
 
-	return !!(value & REG_CONTROL3_BLF);
+	return !!(value & PCF8523_CONTROL3_BLF);
 }
 
 static int pcf8523_load_capacitance(struct i2c_client *client)
@@ -112,7 +112,7 @@ static int pcf8523_load_capacitance(struct i2c_client *client)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL1, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
 
@@ -126,14 +126,14 @@ static int pcf8523_load_capacitance(struct i2c_client *client)
 			 load);
 		fallthrough;
 	case 12500:
-		value |= REG_CONTROL1_CAP_SEL;
+		value |= PCF8523_CONTROL1_CAP_SEL;
 		break;
 	case 7000:
-		value &= ~REG_CONTROL1_CAP_SEL;
+		value &= ~PCF8523_CONTROL1_CAP_SEL;
 		break;
 	}
 
-	err = pcf8523_write(client, REG_CONTROL1, value);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL1, value);
 
 	return err;
 }
@@ -143,13 +143,13 @@ static int pcf8523_set_pm(struct i2c_client *client, u8 pm)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL3, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL3, &value);
 	if (err < 0)
 		return err;
 
-	value = (value & ~REG_CONTROL3_PM_MASK) | pm;
+	value = (value & ~PCF8523_CONTROL3_PM_MASK) | pm;
 
-	err = pcf8523_write(client, REG_CONTROL3, value);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL3, value);
 	if (err < 0)
 		return err;
 
@@ -162,13 +162,13 @@ static irqreturn_t pcf8523_irq(int irq, void *dev_id)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(pcf8523->client, REG_CONTROL2, &value);
+	err = pcf8523_read(pcf8523->client, PCF8523_REG_CONTROL2, &value);
 	if (err < 0)
 		return IRQ_HANDLED;
 
-	if (value & REG_CONTROL2_AF) {
-		value &= ~REG_CONTROL2_AF;
-		pcf8523_write(pcf8523->client, REG_CONTROL2, value);
+	if (value & PCF8523_CONTROL2_AF) {
+		value &= ~PCF8523_CONTROL2_AF;
+		pcf8523_write(pcf8523->client, PCF8523_REG_CONTROL2, value);
 		rtc_update_irq(pcf8523->rtc, 1, RTC_IRQF | RTC_AF);
 
 		return IRQ_HANDLED;
@@ -182,13 +182,13 @@ static int pcf8523_stop_rtc(struct i2c_client *client)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL1, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
 
-	value |= REG_CONTROL1_STOP;
+	value |= PCF8523_CONTROL1_STOP;
 
-	err = pcf8523_write(client, REG_CONTROL1, value);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL1, value);
 	if (err < 0)
 		return err;
 
@@ -200,13 +200,13 @@ static int pcf8523_start_rtc(struct i2c_client *client)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL1, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
 
-	value &= ~REG_CONTROL1_STOP;
+	value &= ~PCF8523_CONTROL1_STOP;
 
-	err = pcf8523_write(client, REG_CONTROL1, value);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL1, value);
 	if (err < 0)
 		return err;
 
@@ -216,7 +216,7 @@ static int pcf8523_start_rtc(struct i2c_client *client)
 static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	u8 start = REG_SECONDS, regs[7];
+	u8 start = PCF8523_REG_SECONDS, regs[7];
 	struct i2c_msg msgs[2];
 	int err;
 
@@ -242,7 +242,7 @@ static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	if (err < 0)
 		return err;
 
-	if (regs[0] & REG_SECONDS_OS)
+	if (regs[0] & PCF8523_SECONDS_OS)
 		return -EINVAL;
 
 	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
@@ -267,8 +267,8 @@ static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	if (err < 0)
 		return err;
 
-	regs[0] = REG_SECONDS;
-	/* This will purposely overwrite REG_SECONDS_OS */
+	regs[0] = PCF8523_REG_SECONDS;
+	/* This will purposely overwrite PCF8523_SECONDS_OS */
 	regs[1] = bin2bcd(tm->tm_sec);
 	regs[2] = bin2bcd(tm->tm_min);
 	regs[3] = bin2bcd(tm->tm_hour);
@@ -299,7 +299,7 @@ static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm)
 static int pcf8523_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	u8 start = REG_MINUTE_ALARM, regs[4];
+	u8 start = PCF8523_REG_MINUTE_ALARM, regs[4];
 	struct i2c_msg msgs[2];
 	u8 value;
 	int err;
@@ -324,15 +324,15 @@ static int pcf8523_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm)
 	tm->time.tm_mday = bcd2bin(regs[2] & 0x3F);
 	tm->time.tm_wday = bcd2bin(regs[3] & 0x7);
 
-	err = pcf8523_read(client, REG_CONTROL1, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
-	tm->enabled = !!(value & REG_CONTROL1_AIE);
+	tm->enabled = !!(value & PCF8523_CONTROL1_AIE);
 
-	err = pcf8523_read(client, REG_CONTROL2, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL2, &value);
 	if (err < 0)
 		return err;
-	tm->pending = !!(value & REG_CONTROL2_AF);
+	tm->pending = !!(value & PCF8523_CONTROL2_AF);
 
 	return 0;
 }
@@ -343,16 +343,16 @@ static int pcf8523_irq_enable(struct device *dev, unsigned int enabled)
 	u8 value;
 	int err;
 
-	err = pcf8523_read(client, REG_CONTROL1, &value);
+	err = pcf8523_read(client, PCF8523_REG_CONTROL1, &value);
 	if (err < 0)
 		return err;
 
-	value &= REG_CONTROL1_AIE;
+	value &= PCF8523_CONTROL1_AIE;
 
 	if (enabled)
-		value |= REG_CONTROL1_AIE;
+		value |= PCF8523_CONTROL1_AIE;
 
-	err = pcf8523_write(client, REG_CONTROL1, value);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL1, value);
 	if (err < 0)
 		return err;
 
@@ -370,7 +370,7 @@ static int pcf8523_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
 	if (err)
 		return err;
 
-	err = pcf8523_write(client, REG_CONTROL2, 0);
+	err = pcf8523_write(client, PCF8523_REG_CONTROL2, 0);
 	if (err < 0)
 		return err;
 
@@ -382,7 +382,7 @@ static int pcf8523_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
 		rtc_time64_to_tm(alarm_time, &tm->time);
 	}
 
-	regs[0] = REG_MINUTE_ALARM;
+	regs[0] = PCF8523_REG_MINUTE_ALARM;
 	regs[1] = bin2bcd(tm->time.tm_min);
 	regs[2] = bin2bcd(tm->time.tm_hour);
 	regs[3] = bin2bcd(tm->time.tm_mday);
@@ -418,11 +418,11 @@ static int pcf8523_rtc_ioctl(struct device *dev, unsigned int cmd,
 		if (ret)
 			flags |= RTC_VL_BACKUP_LOW;
 
-		ret = pcf8523_read(client, REG_SECONDS, &value);
+		ret = pcf8523_read(client, PCF8523_REG_SECONDS, &value);
 		if (ret < 0)
 			return ret;
 
-		if (value & REG_SECONDS_OS)
+		if (value & PCF8523_SECONDS_OS)
 			flags |= RTC_VL_DATA_INVALID;
 
 		return put_user(flags, (unsigned int __user *)arg);
@@ -442,13 +442,13 @@ static int pcf8523_rtc_read_offset(struct device *dev, long *offset)
 	u8 value;
 	s8 val;
 
-	err = pcf8523_read(client, REG_OFFSET, &value);
+	err = pcf8523_read(client, PCF8523_REG_OFFSET, &value);
 	if (err < 0)
 		return err;
 
 	/* sign extend the 7-bit offset value */
 	val = value << 1;
-	*offset = (value & REG_OFFSET_MODE ? 4069 : 4340) * (val >> 1);
+	*offset = (value & PCF8523_OFFSET_MODE ? 4069 : 4340) * (val >> 1);
 
 	return 0;
 }
@@ -465,9 +465,9 @@ static int pcf8523_rtc_set_offset(struct device *dev, long offset)
 	if (abs(reg_m0 * 4340 - offset) < abs(reg_m1 * 4069 - offset))
 		value = reg_m0 & 0x7f;
 	else
-		value = (reg_m1 & 0x7f) | REG_OFFSET_MODE;
+		value = (reg_m1 & 0x7f) | PCF8523_OFFSET_MODE;
 
-	return pcf8523_write(client, REG_OFFSET, value);
+	return pcf8523_write(client, PCF8523_REG_OFFSET, value);
 }
 
 static const struct rtc_class_ops pcf8523_rtc_ops = {
@@ -519,7 +519,7 @@ static int pcf8523_probe(struct i2c_client *client,
 	rtc->uie_unsupported = 1;
 
 	if (client->irq > 0) {
-		err = pcf8523_write(client, REG_TMR_CLKOUT_CTRL, 0x38);
+		err = pcf8523_write(client, PCF8523_TMR_CLKOUT_CTRL, 0x38);
 		if (err < 0)
 			return err;
 
diff --git a/drivers/rtc/rtc-pcf8563.c b/drivers/rtc/rtc-pcf8563.c
index 18f12f36eb2b..c8bddfb94129 100644
--- a/drivers/rtc/rtc-pcf8563.c
+++ b/drivers/rtc/rtc-pcf8563.c
@@ -8,7 +8,7 @@
  *
  * based on the other drivers in this same directory.
  *
- * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf
+ * https://www.nxp.com/docs/en/data-sheet/PCF8563.pdf
  */
 
 #include <linux/clk-provider.h>
diff --git a/drivers/rtc/rtc-rtd119x.c b/drivers/rtc/rtc-rtd119x.c
index bb98f2d574a5..8f9abd65846c 100644
--- a/drivers/rtc/rtc-rtd119x.c
+++ b/drivers/rtc/rtc-rtd119x.c
@@ -1,9 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Realtek RTD129x RTC
  *
  * Copyright (c) 2017 Andreas Färber
- *
- * SPDX-License-Identifier: GPL-2.0+
  */
 
 #include <linux/clk.h>
diff --git a/drivers/rtc/rtc-rx8025.c b/drivers/rtc/rtc-rx8025.c
index c914091819ba..d38aaf08108c 100644
--- a/drivers/rtc/rtc-rx8025.c
+++ b/drivers/rtc/rtc-rx8025.c
@@ -60,14 +60,23 @@
 #define RX8025_ADJ_DATA_MAX	62
 #define RX8025_ADJ_DATA_MIN	-62
 
+enum rx_model {
+	model_rx_unknown,
+	model_rx_8025,
+	model_rx_8035,
+	model_last
+};
+
 static const struct i2c_device_id rx8025_id[] = {
-	{ "rx8025", 0 },
+	{ "rx8025", model_rx_8025 },
+	{ "rx8035", model_rx_8035 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, rx8025_id);
 
 struct rx8025_data {
 	struct rtc_device *rtc;
+	enum rx_model model;
 	u8 ctrl1;
 };
 
@@ -100,10 +109,26 @@ static s32 rx8025_write_regs(const struct i2c_client *client,
 					      length, values);
 }
 
+static int rx8025_is_osc_stopped(enum rx_model model, int ctrl2)
+{
+	int xstp = ctrl2 & RX8025_BIT_CTRL2_XST;
+	/* XSTP bit has different polarity on RX-8025 vs RX-8035.
+	 * RX-8025: 0 == oscillator stopped
+	 * RX-8035: 1 == oscillator stopped
+	 */
+
+	if (model == model_rx_8025)
+		xstp = !xstp;
+
+	return xstp;
+}
+
 static int rx8025_check_validity(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
+	struct rx8025_data *drvdata = dev_get_drvdata(dev);
 	int ctrl2;
+	int xstp;
 
 	ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);
 	if (ctrl2 < 0)
@@ -117,7 +142,8 @@ static int rx8025_check_validity(struct device *dev)
 		return -EINVAL;
 	}
 
-	if (!(ctrl2 & RX8025_BIT_CTRL2_XST)) {
+	xstp = rx8025_is_osc_stopped(drvdata->model, ctrl2);
+	if (xstp) {
 		dev_warn(dev, "crystal stopped, date is invalid\n");
 		return -EINVAL;
 	}
@@ -127,6 +153,7 @@ static int rx8025_check_validity(struct device *dev)
 
 static int rx8025_reset_validity(struct i2c_client *client)
 {
+	struct rx8025_data *drvdata = i2c_get_clientdata(client);
 	int ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);
 
 	if (ctrl2 < 0)
@@ -134,22 +161,28 @@ static int rx8025_reset_validity(struct i2c_client *client)
 
 	ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET);
 
+	if (drvdata->model == model_rx_8025)
+		ctrl2 |= RX8025_BIT_CTRL2_XST;
+	else
+		ctrl2 &= ~(RX8025_BIT_CTRL2_XST);
+
 	return rx8025_write_reg(client, RX8025_REG_CTRL2,
-				ctrl2 | RX8025_BIT_CTRL2_XST);
+				ctrl2);
 }
 
 static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)
 {
 	struct i2c_client *client = dev_id;
 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
-	int status;
+	int status, xstp;
 
 	rtc_lock(rx8025->rtc);
 	status = rx8025_read_reg(client, RX8025_REG_CTRL2);
 	if (status < 0)
 		goto out;
 
-	if (!(status & RX8025_BIT_CTRL2_XST))
+	xstp = rx8025_is_osc_stopped(rx8025->model, status);
+	if (xstp)
 		dev_warn(&client->dev, "Oscillation stop was detected,"
 			 "you may have to readjust the clock\n");
 
@@ -519,6 +552,9 @@ static int rx8025_probe(struct i2c_client *client,
 
 	i2c_set_clientdata(client, rx8025);
 
+	if (id)
+		rx8025->model = id->driver_data;
+
 	err = rx8025_init_client(client);
 	if (err)
 		return err;
diff --git a/drivers/rtc/rtc-s5m.c b/drivers/rtc/rtc-s5m.c
index 038269a6b08c..fb9c6b709e13 100644
--- a/drivers/rtc/rtc-s5m.c
+++ b/drivers/rtc/rtc-s5m.c
@@ -204,15 +204,9 @@ static int s5m8767_tm_to_data(struct rtc_time *tm, u8 *data)
 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
 	data[RTC_DATE] = tm->tm_mday;
 	data[RTC_MONTH] = tm->tm_mon + 1;
-	data[RTC_YEAR1] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
+	data[RTC_YEAR1] = tm->tm_year - 100;
 
-	if (tm->tm_year < 100) {
-		pr_err("RTC cannot handle the year %d\n",
-		       1900 + tm->tm_year);
-		return -EINVAL;
-	} else {
-		return 0;
-	}
+	return 0;
 }
 
 /*
@@ -488,9 +482,7 @@ static int s5m_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 
 	dev_dbg(dev, "%s: %ptR(%d)\n", __func__, &alrm->time, alrm->time.tm_wday);
 
-	ret = s5m_check_peding_alarm_interrupt(info, alrm);
-
-	return 0;
+	return s5m_check_peding_alarm_interrupt(info, alrm);
 }
 
 static int s5m_rtc_stop_alarm(struct s5m_rtc_info *info)
@@ -788,29 +780,35 @@ static int s5m_rtc_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	device_init_wakeup(&pdev->dev, 1);
-
-	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "s5m-rtc",
-						 &s5m_rtc_ops, THIS_MODULE);
-
+	info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
 	if (IS_ERR(info->rtc_dev))
 		return PTR_ERR(info->rtc_dev);
 
-	if (!info->irq) {
-		dev_info(&pdev->dev, "Alarm IRQ not available\n");
-		return 0;
+	info->rtc_dev->ops = &s5m_rtc_ops;
+
+	if (info->device_type == S5M8763X) {
+		info->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_0000;
+		info->rtc_dev->range_max = RTC_TIMESTAMP_END_9999;
+	} else {
+		info->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
+		info->rtc_dev->range_max = RTC_TIMESTAMP_END_2099;
 	}
 
-	ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
-					s5m_rtc_alarm_irq, 0, "rtc-alarm0",
-					info);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
-			info->irq, ret);
-		return ret;
+	if (!info->irq) {
+		clear_bit(RTC_FEATURE_ALARM, info->rtc_dev->features);
+	} else {
+		ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
+						s5m_rtc_alarm_irq, 0, "rtc-alarm0",
+						info);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
+				info->irq, ret);
+			return ret;
+		}
+		device_init_wakeup(&pdev->dev, 1);
 	}
 
-	return 0;
+	return devm_rtc_register_device(info->rtc_dev);
 }
 
 #ifdef CONFIG_PM_SLEEP
diff --git a/drivers/rtc/rtc-sc27xx.c b/drivers/rtc/rtc-sc27xx.c
index 187aa955b79c..ce7a2ddbbc16 100644
--- a/drivers/rtc/rtc-sc27xx.c
+++ b/drivers/rtc/rtc-sc27xx.c
@@ -1,7 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2017 Spreadtrum Communications Inc.
  *
- * SPDX-License-Identifier: GPL-2.0
  */
 
 #include <linux/bitops.h>
diff --git a/drivers/rtc/rtc-spear.c b/drivers/rtc/rtc-spear.c
index ee721e53c155..b4a520056b1a 100644
--- a/drivers/rtc/rtc-spear.c
+++ b/drivers/rtc/rtc-spear.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * drivers/rtc/rtc-spear.c
  *
  * Copyright (C) 2010 ST Microelectronics
  * Rajeev Kumar<rajeev-dlh.kumar@st.com>
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
  */
 
 #include <linux/bcd.h>
diff --git a/drivers/rtc/rtc-stm32.c b/drivers/rtc/rtc-stm32.c
index 75a8924ba12b..ac9e228b56d0 100644
--- a/drivers/rtc/rtc-stm32.c
+++ b/drivers/rtc/rtc-stm32.c
@@ -754,7 +754,7 @@ static int stm32_rtc_probe(struct platform_device *pdev)
 
 	ret = clk_prepare_enable(rtc->rtc_ck);
 	if (ret)
-		goto err;
+		goto err_no_rtc_ck;
 
 	if (rtc->data->need_dbp)
 		regmap_update_bits(rtc->dbp, rtc->dbp_reg,
@@ -830,10 +830,12 @@ static int stm32_rtc_probe(struct platform_device *pdev)
 	}
 
 	return 0;
+
 err:
+	clk_disable_unprepare(rtc->rtc_ck);
+err_no_rtc_ck:
 	if (rtc->data->has_pclk)
 		clk_disable_unprepare(rtc->pclk);
-	clk_disable_unprepare(rtc->rtc_ck);
 
 	if (rtc->data->need_dbp)
 		regmap_update_bits(rtc->dbp, rtc->dbp_reg, rtc->dbp_mask, 0);
diff --git a/drivers/rtc/rtc-tps6586x.c b/drivers/rtc/rtc-tps6586x.c
index a980337c3065..52093e7ba22d 100644
--- a/drivers/rtc/rtc-tps6586x.c
+++ b/drivers/rtc/rtc-tps6586x.c
@@ -1,23 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * rtc-tps6586x.c: RTC driver for TI PMIC TPS6586X
  *
  * Copyright (c) 2012, NVIDIA Corporation.
  *
  * Author: Laxman Dewangan <ldewangan@nvidia.com>
- *
- * 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 version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
- * whether express or implied; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- * 02111-1307, USA
  */
 
 #include <linux/device.h>
diff --git a/drivers/rtc/rtc-tps65910.c b/drivers/rtc/rtc-tps65910.c
index bc89c62ccb9b..75e4c2d777b9 100644
--- a/drivers/rtc/rtc-tps65910.c
+++ b/drivers/rtc/rtc-tps65910.c
@@ -467,6 +467,6 @@ static struct platform_driver tps65910_rtc_driver = {
 };
 
 module_platform_driver(tps65910_rtc_driver);
-MODULE_ALIAS("platform:rtc-tps65910");
+MODULE_ALIAS("platform:tps65910-rtc");
 MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
 MODULE_LICENSE("GPL");
diff --git a/drivers/rtc/rtc-tps80031.c b/drivers/rtc/rtc-tps80031.c
index 737f26eb284a..c77b8eab94a0 100644
--- a/drivers/rtc/rtc-tps80031.c
+++ b/drivers/rtc/rtc-tps80031.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * rtc-tps80031.c -- TI TPS80031/TPS80032 RTC driver
  *
@@ -7,20 +8,6 @@
  * Copyright (c) 2012, NVIDIA Corporation.
  *
  * Author: Laxman Dewangan <ldewangan@nvidia.com>
- *
- * 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 version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
- * whether express or implied; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- * 02111-1307, USA
  */
 
 #include <linux/bcd.h>
diff --git a/drivers/rtc/rtc-v3020.c b/drivers/rtc/rtc-v3020.c
index d2da92187d56..4e8341c49f51 100644
--- a/drivers/rtc/rtc-v3020.c
+++ b/drivers/rtc/rtc-v3020.c
@@ -282,7 +282,7 @@ static int rtc_probe(struct platform_device *pdev)
 {
 	struct v3020_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct v3020 *chip;
-	int retval = -EBUSY;
+	int retval;
 	int i;
 
 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
diff --git a/drivers/rtc/sysfs.c b/drivers/rtc/sysfs.c
index 74026f67fdfb..00f1945bcb7e 100644
--- a/drivers/rtc/sysfs.c
+++ b/drivers/rtc/sysfs.c
@@ -102,7 +102,7 @@ max_user_freq_store(struct device *dev, struct device_attribute *attr,
 static DEVICE_ATTR_RW(max_user_freq);
 
 /**
- * rtc_sysfs_show_hctosys - indicate if the given RTC set the system time
+ * hctosys_show - indicate if the given RTC set the system time
  * @dev: The device that the attribute belongs to.
  * @attr: The attribute being read.
  * @buf: The result buffer.