[RFC PATCH 09/13] mfd: rtc: support RTC on ROHM BD71828 with BD70528 driver

[Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>]

ROHM BD71828 PMIC RTC block is from many parts similar to one
on BD70528. Support BD71828 RTC using BD70528 RTC driver and
avoid re-inventing the wheel.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
---
 drivers/rtc/Kconfig              |   5 +-
 drivers/rtc/rtc-bd70528.c        | 369 ++++++++++++++++++++++---------
 include/linux/mfd/rohm-bd70528.h |  12 +-
 include/linux/mfd/rohm-bd71828.h |   4 +-
 include/linux/mfd/rohm-shared.h  |  22 ++
 5 files changed, 299 insertions(+), 113 deletions(-)
 create mode 100644 include/linux/mfd/rohm-shared.h

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index e72f65b61176..5c5b18a99bf9 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -498,11 +498,12 @@ config RTC_DRV_M41T80_WDT
 	help
 	  If you say Y here you will get support for the
 	  watchdog timer in the ST M41T60 and M41T80 RTC chips series.
+
 config RTC_DRV_BD70528
-	tristate "ROHM BD70528 PMIC RTC"
+	tristate "ROHM BD70528 and BD71828 PMIC RTC"
 	help
 	  If you say Y here you will get support for the RTC
-	  on ROHM BD70528 Power Management IC.
+	  block on ROHM BD70528 and BD71828 Power Management IC.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-bd70528.
diff --git a/drivers/rtc/rtc-bd70528.c b/drivers/rtc/rtc-bd70528.c
index f9bdd555e1a2..2940b57002ac 100644
--- a/drivers/rtc/rtc-bd70528.c
+++ b/drivers/rtc/rtc-bd70528.c
@@ -2,10 +2,11 @@
 //
 // Copyright (C) 2018 ROHM Semiconductors
 //
-// RTC driver for ROHM BD70528 PMIC
+// RTC driver for ROHM BD70528 and BD71828 PMICs
 
 #include <linux/bcd.h>
 #include <linux/mfd/rohm-bd70528.h>
+#include <linux/mfd/rohm-bd71828.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -15,16 +16,16 @@
 /*
  * We read regs RTC_SEC => RTC_YEAR
  * this struct is ordered according to chip registers.
- * Keep it u8 only to avoid padding issues.
+ * Keep it u8 only (or packed) to avoid padding issues.
  */
-struct bd70528_rtc_day {
+struct bd7xx28_rtc_day {
 	u8 sec;
 	u8 min;
 	u8 hour;
 } __packed;
 
-struct bd70528_rtc_data {
-	struct bd70528_rtc_day time;
+struct bd7xx28_rtc_data {
+	struct bd7xx28_rtc_day time;
 	u8 week;
 	u8 day;
 	u8 month;
@@ -32,19 +33,28 @@ struct bd70528_rtc_data {
 } __packed;
 
 struct bd70528_rtc_wake {
-	struct bd70528_rtc_day time;
+	struct bd7xx28_rtc_day time;
 	u8 ctrl;
 } __packed;
 
+struct bd71828_rtc_alm {
+	struct bd7xx28_rtc_data alm0;
+	struct bd7xx28_rtc_data alm1;
+	u8 alm_mask;
+	u8 alm1_mask;
+} __packed;
+
 struct bd70528_rtc_alm {
-	struct bd70528_rtc_data data;
+	struct bd7xx28_rtc_data data;
 	u8 alm_mask;
 	u8 alm_repeat;
 } __packed;
 
-struct bd70528_rtc {
+struct bd7xx28_rtc {
 	struct rohm_regmap_dev *mfd;
 	struct device *dev;
+	u8 reg_time_start;
+	bool has_rtc_timers;
 };
 
 static int bd70528_set_wake(struct rohm_regmap_dev *bd70528,
@@ -118,7 +128,7 @@ static int bd70528_set_elapsed_tmr(struct rohm_regmap_dev *bd70528,
 			    ctrl_reg);
 }
 
-static int bd70528_set_rtc_based_timers(struct bd70528_rtc *r, int new_state,
+static int bd70528_set_rtc_based_timers(struct bd7xx28_rtc *r, int new_state,
 					int *old_state)
 {
 	int ret;
@@ -127,122 +137,162 @@ static int bd70528_set_rtc_based_timers(struct bd70528_rtc *r, int new_state,
 			      old_state);
 	if (ret) {
 		dev_err(r->dev,
-			"Failed to disable WDG for RTC setting (%d)\n", ret);
+			"Failed to disable WDG for RTC setting (%d)\n",
+			ret);
 		return ret;
 	}
-	ret = bd70528_set_elapsed_tmr(r->mfd,
-				      new_state & BD70528_ELAPSED_STATE_BIT,
+	ret = bd70528_set_elapsed_tmr(r->mfd, 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->mfd, new_state & BD70528_WAKE_STATE_BIT,
-			       old_state);
+
+	ret = bd70528_set_wake(r->mfd, new_state &
+			       BD70528_WAKE_STATE_BIT, old_state);
 	if (ret) {
 		dev_err(r->dev,
-			"Failed to disable 'wake timer' for RTC setting\n");
+			"Failed to disable 'wake timer'\n");
 		return ret;
 	}
 
 	return ret;
 }
 
-static int bd70528_re_enable_rtc_based_timers(struct bd70528_rtc *r,
+static int bd7xx28_re_enable_rtc_based_timers(struct bd7xx28_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,
+static int bd7xx28_disable_rtc_based_timers(struct bd7xx28_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)
+static inline void tmday2rtc(struct rtc_time *t, struct bd7xx28_rtc_day *d)
 {
-	d->sec &= ~BD70528_MASK_RTC_SEC;
-	d->min &= ~BD70528_MASK_RTC_MINUTE;
-	d->hour &= ~BD70528_MASK_RTC_HOUR;
+	d->sec &= ~ROHM_BD1_MASK_RTC_SEC;
+	d->min &= ~ROHM_BD1_MASK_RTC_MINUTE;
+	d->hour &= ~ROHM_BD1_MASK_RTC_HOUR;
 	d->sec |= bin2bcd(t->tm_sec);
 	d->min |= bin2bcd(t->tm_min);
 	d->hour |= bin2bcd(t->tm_hour);
 }
 
-static inline void tm2rtc(struct rtc_time *t, struct bd70528_rtc_data *r)
+static inline void tm2rtc(struct rtc_time *t, struct bd7xx28_rtc_data *r)
 {
-	r->day &= ~BD70528_MASK_RTC_DAY;
-	r->week &= ~BD70528_MASK_RTC_WEEK;
-	r->month &= ~BD70528_MASK_RTC_MONTH;
+	r->day &= ~ROHM_BD1_MASK_RTC_DAY;
+	r->week &= ~ROHM_BD1_MASK_RTC_WEEK;
+	r->month &= ~ROHM_BD1_MASK_RTC_MONTH;
 	/*
 	 * PM and 24H bits are not used by Wake - thus we clear them
 	 * here and not in tmday2rtc() which is also used by wake.
 	 */
-	r->time.hour &= ~(BD70528_MASK_RTC_HOUR_PM | BD70528_MASK_RTC_HOUR_24H);
+	r->time.hour &= ~(ROHM_BD1_MASK_RTC_HOUR_PM |
+			  ROHM_BD1_MASK_RTC_HOUR_24H);
 
 	tmday2rtc(t, &r->time);
 	/*
 	 * We do always set time in 24H mode.
 	 */
-	r->time.hour |= BD70528_MASK_RTC_HOUR_24H;
+	r->time.hour |= ROHM_BD1_MASK_RTC_HOUR_24H;
 	r->day |= bin2bcd(t->tm_mday);
 	r->week |= bin2bcd(t->tm_wday);
 	r->month |= bin2bcd(t->tm_mon + 1);
 	r->year = bin2bcd(t->tm_year - 100);
+
 }
 
-static inline void rtc2tm(struct bd70528_rtc_data *r, struct rtc_time *t)
+static inline void rtc2tm(struct bd7xx28_rtc_data *r, struct rtc_time *t)
 {
-	t->tm_sec = bcd2bin(r->time.sec & BD70528_MASK_RTC_SEC);
-	t->tm_min = bcd2bin(r->time.min & BD70528_MASK_RTC_MINUTE);
-	t->tm_hour = bcd2bin(r->time.hour & BD70528_MASK_RTC_HOUR);
+	t->tm_sec = bcd2bin(r->time.sec & ROHM_BD1_MASK_RTC_SEC);
+	t->tm_min = bcd2bin(r->time.min & ROHM_BD1_MASK_RTC_MINUTE);
+	t->tm_hour = bcd2bin(r->time.hour & ROHM_BD1_MASK_RTC_HOUR);
 	/*
-	 * If RTC is in 12H mode, then bit BD70528_MASK_RTC_HOUR_PM
+	 * If RTC is in 12H mode, then bit ROHM_BD1_MASK_RTC_HOUR_PM
 	 * is not BCD value but tells whether it is AM or PM
 	 */
-	if (!(r->time.hour & BD70528_MASK_RTC_HOUR_24H)) {
+	if (!(r->time.hour & ROHM_BD1_MASK_RTC_HOUR_24H)) {
 		t->tm_hour %= 12;
-		if (r->time.hour & BD70528_MASK_RTC_HOUR_PM)
+		if (r->time.hour & ROHM_BD1_MASK_RTC_HOUR_PM)
 			t->tm_hour += 12;
 	}
-	t->tm_mday = bcd2bin(r->day & BD70528_MASK_RTC_DAY);
-	t->tm_mon = bcd2bin(r->month & BD70528_MASK_RTC_MONTH) - 1;
-	t->tm_year = 100 + bcd2bin(r->year & BD70528_MASK_RTC_YEAR);
-	t->tm_wday = bcd2bin(r->week & BD70528_MASK_RTC_WEEK);
+	t->tm_mday = bcd2bin(r->day & ROHM_BD1_MASK_RTC_DAY);
+	t->tm_mon = bcd2bin(r->month & ROHM_BD1_MASK_RTC_MONTH) - 1;
+	t->tm_year = 100 + bcd2bin(r->year & ROHM_BD1_MASK_RTC_YEAR);
+	t->tm_wday = bcd2bin(r->week & ROHM_BD1_MASK_RTC_WEEK);
 }
 
-static int bd70528_set_alarm(struct device *dev, struct rtc_wkalrm *a)
+static int bd71828_set_alarm(struct bd7xx28_rtc *r, struct rtc_wkalrm *a)
+{
+	int ret;
+	struct bd71828_rtc_alm alm;
+	struct rohm_regmap_dev *bd71828 = r->mfd;
+
+	ret = regmap_bulk_read(bd71828->regmap, BD71828_REG_RTC_ALM_START,
+			       &alm, sizeof(alm));
+	if (ret) {
+		dev_err(r->dev, "Failed to read alarm regs\n");
+		return ret;
+	}
+
+	tm2rtc(&a->time, &alm.alm0);
+
+	if (!a->enabled)
+		alm.alm_mask &= ~ROHM_BD1_MASK_ALM_EN;
+	else
+		alm.alm_mask |= ROHM_BD1_MASK_ALM_EN;
+
+	pr_debug("%s: new ALM0 EN bits are 0x%x\n", __func__, alm.alm_mask);
+
+	ret = regmap_bulk_write(bd71828->regmap, BD71828_REG_RTC_ALM_START,
+				&alm, sizeof(alm));
+	if (ret)
+		dev_err(r->dev, "Failed to set alarm time\n");
+
+	return ret;
+
+}
+static int bd70528_set_alarm(struct bd7xx28_rtc *r, struct rtc_wkalrm *a)
 {
 	struct bd70528_rtc_wake wake;
 	struct bd70528_rtc_alm alm;
 	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
 	struct rohm_regmap_dev *bd70528 = r->mfd;
 
-	ret = regmap_bulk_read(bd70528->regmap, BD70528_REG_RTC_WAKE_START,
+	ret = regmap_bulk_read(bd70528->regmap,
+			       BD70528_REG_RTC_WAKE_START,
 			       &wake, sizeof(wake));
 	if (ret) {
-		dev_err(dev, "Failed to read wake regs\n");
+		dev_err(r->dev, "Failed to read wake regs\n");
 		return ret;
 	}
+	tmday2rtc(&a->time, &wake.time);
 
 	ret = regmap_bulk_read(bd70528->regmap, BD70528_REG_RTC_ALM_START,
 			       &alm, sizeof(alm));
 	if (ret) {
-		dev_err(dev, "Failed to read alarm regs\n");
+		dev_err(r->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;
+		alm.alm_mask &= ~ROHM_BD1_MASK_ALM_EN;
 		wake.ctrl |= BD70528_MASK_WAKE_EN;
 	} else {
-		alm.alm_mask |= BD70528_MASK_ALM_EN;
+		alm.alm_mask |= ROHM_BD1_MASK_ALM_EN;
 		wake.ctrl &= ~BD70528_MASK_WAKE_EN;
 	}
 
@@ -250,28 +300,69 @@ static int bd70528_set_alarm(struct device *dev, struct rtc_wkalrm *a)
 				BD70528_REG_RTC_WAKE_START, &wake,
 				sizeof(wake));
 	if (ret) {
-		dev_err(dev, "Failed to set wake time\n");
+		dev_err(r->dev, "Failed to set wake time\n");
 		return ret;
 	}
 	ret = regmap_bulk_write(bd70528->regmap, BD70528_REG_RTC_ALM_START,
 				&alm, sizeof(alm));
 	if (ret)
-		dev_err(dev, "Failed to set alarm time\n");
+		dev_err(r->dev, "Failed to set alarm time\n");
 
 	return ret;
 }
+static int bd7xx28_set_alarm(struct device *dev, struct rtc_wkalrm *a)
+{
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
+	struct rohm_regmap_dev *bd_dev = r->mfd;
+
+	switch (bd_dev->chip_type) {
+	case ROHM_CHIP_TYPE_BD70528:
+		return bd70528_set_alarm(r, a);
+	case ROHM_CHIP_TYPE_BD71828:
+		return bd71828_set_alarm(r, a);
+	default:
+		dev_err(dev, "Unknown RTC chip\n");
+		break;
+	}
+
+	return -ENOENT;
+}
 
-static int bd70528_read_alarm(struct device *dev, struct rtc_wkalrm *a)
+static int bd71828_read_alarm(struct bd7xx28_rtc *r, struct rtc_wkalrm *a)
+{
+	int ret;
+	struct bd71828_rtc_alm alm;
+	struct rohm_regmap_dev *bd71828 = r->mfd;
+
+	ret = regmap_bulk_read(bd71828->regmap, BD71828_REG_RTC_ALM_START,
+			       &alm, sizeof(alm));
+	if (ret) {
+		dev_err(r->dev, "Failed to read alarm regs\n");
+		return ret;
+	}
+
+	rtc2tm(&alm.alm0, &a->time);
+	a->time.tm_mday = -1;
+	a->time.tm_mon = -1;
+	a->time.tm_year = -1;
+	a->enabled = !!(alm.alm_mask & ROHM_BD1_MASK_ALM_EN);
+	a->pending = 0;
+	pr_debug("%s: ALM0 EN bits are 0x%x, returniong enabled %d\n", __func__,
+		alm.alm_mask, a->enabled);
+
+	return 0;
+}
+
+static int bd70528_read_alarm(struct bd7xx28_rtc *r, struct rtc_wkalrm *a)
 {
-	struct bd70528_rtc_alm alm;
 	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
+	struct bd70528_rtc_alm alm;
 	struct rohm_regmap_dev *bd70528 = r->mfd;
 
 	ret = regmap_bulk_read(bd70528->regmap, BD70528_REG_RTC_ALM_START,
 			       &alm, sizeof(alm));
 	if (ret) {
-		dev_err(dev, "Failed to read alarm regs\n");
+		dev_err(r->dev, "Failed to read alarm regs\n");
 		return ret;
 	}
 
@@ -279,25 +370,42 @@ static int bd70528_read_alarm(struct device *dev, struct rtc_wkalrm *a)
 	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->enabled = !(alm.alm_mask & ROHM_BD1_MASK_ALM_EN);
 	a->pending = 0;
 
 	return 0;
 }
 
-static int bd70528_set_time_locked(struct device *dev, struct rtc_time *t)
+static int bd7xx28_read_alarm(struct device *dev, struct rtc_wkalrm *a)
+{
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
+	struct rohm_regmap_dev *bd_dev = r->mfd;
+
+	switch (bd_dev->chip_type) {
+	case ROHM_CHIP_TYPE_BD70528:
+		return bd70528_read_alarm(r, a);
+	case ROHM_CHIP_TYPE_BD71828:
+		return bd71828_read_alarm(r, a);
+	default:
+		dev_err(dev, "Unknown RTC chip\n");
+		break;
+	}
+	return -ENOENT;
+}
+
+static int bd7xx28_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);
-	struct rohm_regmap_dev *bd70528 = r->mfd;
+	struct bd7xx28_rtc_data rtc_data;
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
+	struct rohm_regmap_dev *bd7xx28 = r->mfd;
 
-	ret = bd70528_disable_rtc_based_timers(r, &old_states);
+	ret = bd7xx28_disable_rtc_based_timers(r, &old_states);
 	if (ret)
 		return ret;
 
-	tmpret = regmap_bulk_read(bd70528->regmap,
-				  BD70528_REG_RTC_START, &rtc_data,
+	tmpret = regmap_bulk_read(bd7xx28->regmap,
+				  r->reg_time_start, &rtc_data,
 				  sizeof(rtc_data));
 	if (tmpret) {
 		dev_err(dev, "Failed to read RTC time registers\n");
@@ -305,8 +413,8 @@ static int bd70528_set_time_locked(struct device *dev, struct rtc_time *t)
 	}
 	tm2rtc(t, &rtc_data);
 
-	tmpret = regmap_bulk_write(bd70528->regmap,
-				   BD70528_REG_RTC_START, &rtc_data,
+	tmpret = regmap_bulk_write(bd7xx28->regmap,
+				   r->reg_time_start, &rtc_data,
 				   sizeof(rtc_data));
 	if (tmpret) {
 		dev_err(dev, "Failed to set RTC time\n");
@@ -314,34 +422,37 @@ static int bd70528_set_time_locked(struct device *dev, struct rtc_time *t)
 	}
 
 renable_out:
-	ret = bd70528_re_enable_rtc_based_timers(r, old_states);
+	ret = bd7xx28_re_enable_rtc_based_timers(r, old_states);
 	if (tmpret)
 		ret = tmpret;
 
 	return ret;
 }
 
-static int bd70528_set_time(struct device *dev, struct rtc_time *t)
+static int bd7xx28_set_time(struct device *dev, struct rtc_time *t)
 {
 	int ret;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
 
+	pr_debug("%s called\n", __func__);
 	bd70528_wdt_lock(r->mfd);
-	ret = bd70528_set_time_locked(dev, t);
+	ret = bd7xx28_set_time_locked(dev, t);
 	bd70528_wdt_unlock(r->mfd);
 	return ret;
 }
 
-static int bd70528_get_time(struct device *dev, struct rtc_time *t)
+static int bd7xx28_get_time(struct device *dev, struct rtc_time *t)
 {
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
-	struct rohm_regmap_dev *bd70528 = r->mfd;
-	struct bd70528_rtc_data rtc_data;
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
+	struct rohm_regmap_dev *bd7xx28 = r->mfd;
+	struct bd7xx28_rtc_data rtc_data;
 	int ret;
 
+	pr_debug("%s called\n", __func__);
+
 	/* read the RTC date and time registers all at once */
-	ret = regmap_bulk_read(bd70528->regmap,
-			       BD70528_REG_RTC_START, &rtc_data,
+	ret = regmap_bulk_read(bd7xx28->regmap,
+			       r->reg_time_start, &rtc_data,
 			       sizeof(rtc_data));
 	if (ret) {
 		dev_err(dev, "Failed to read RTC time (err %d)\n", ret);
@@ -353,55 +464,94 @@ 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)
+static int bd70528_alm_enable(struct bd7xx28_rtc *r, unsigned int enabled)
 {
 	int ret;
-	unsigned int enableval = BD70528_MASK_ALM_EN;
-	struct bd70528_rtc *r = dev_get_drvdata(dev);
+	unsigned int enableval = ROHM_BD1_MASK_ALM_EN;
 
 	if (enabled)
 		enableval = 0;
 
 	bd70528_wdt_lock(r->mfd);
-	ret = bd70528_set_wake(r->mfd, enabled, NULL);
+	ret = bd70528_set_wake(r->mfd, !enableval, NULL);
 	if (ret) {
-		dev_err(dev, "Failed to change wake state\n");
+		dev_err(r->dev, "Failed to change wake state\n");
 		goto out_unlock;
 	}
 	ret = regmap_update_bits(r->mfd->regmap, BD70528_REG_RTC_ALM_MASK,
-				 BD70528_MASK_ALM_EN, enableval);
+				 ROHM_BD1_MASK_ALM_EN, enableval);
 	if (ret)
-		dev_err(dev, "Failed to change alarm state\n");
+		dev_err(r->dev, "Failed to change alarm state\n");
 
 out_unlock:
 	bd70528_wdt_unlock(r->mfd);
 	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 int bd71828_alm_enable(struct bd7xx28_rtc *r, unsigned int enabled)
+{
+	int ret;
+	unsigned int enableval = ROHM_BD1_MASK_ALM_EN;
+
+	if (!enabled)
+		enableval = 0;
+
+	pr_debug("%s called (enabled=0x%x)\n", __func__, enabled);
+	ret = regmap_update_bits(r->mfd->regmap, BD71828_REG_RTC_ALM0_MASK,
+				 ROHM_BD1_MASK_ALM_EN, enableval);
+	if (ret)
+		dev_err(r->dev, "Failed to change alarm state\n");
+
+	pr_debug("%s: Wrote alm mask reg addr 0x%x val 0x%x\n",
+		__func__, BD71828_REG_RTC_ALM0_MASK, enableval);
+
+	return ret;
+}
+
+static int bd7xx28_alm_enable(struct device *dev, unsigned int enabled)
+{
+	struct bd7xx28_rtc *r = dev_get_drvdata(dev);
+
+	switch (r->mfd->chip_type) {
+	case ROHM_CHIP_TYPE_BD70528:
+		return bd70528_alm_enable(r, enabled);
+	case ROHM_CHIP_TYPE_BD71828:
+		return bd71828_alm_enable(r, enabled);
+	default:
+		dev_err(dev, "Unknown RTC chip\n");
+	}
+
+	return -ENOENT;
+}
+
+static const struct rtc_class_ops bd7xx28_rtc_ops = {
+	.read_time		= bd7xx28_get_time,
+	.set_time		= bd7xx28_set_time,
+	.read_alarm		= bd7xx28_read_alarm,
+	.set_alarm		= bd7xx28_set_alarm,
+	.alarm_irq_enable	= bd7xx28_alm_enable,
 };
 
 static irqreturn_t alm_hndlr(int irq, void *data)
 {
 	struct rtc_device *rtc = data;
 
+	pr_debug("bd71828 RTC IRQ fired\n");
 	rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF | RTC_PF);
 	return IRQ_HANDLED;
 }
 
-static int bd70528_probe(struct platform_device *pdev)
+static int bd7xx28_probe(struct platform_device *pdev)
 {
-	struct bd70528_rtc *bd_rtc;
+	struct bd7xx28_rtc *bd_rtc;
 	struct rohm_regmap_dev *mfd;
+	const char *irq_name;
 	int ret;
 	struct rtc_device *rtc;
 	int irq;
 	unsigned int hr;
+	bool enable_main_irq = false;
+	u8 hour_reg;
 
 	mfd = dev_get_drvdata(pdev->dev.parent);
 	if (!mfd) {
@@ -415,7 +565,25 @@ static int bd70528_probe(struct platform_device *pdev)
 	bd_rtc->mfd = mfd;
 	bd_rtc->dev = &pdev->dev;
 
-	irq = platform_get_irq_byname(pdev, "bd70528-rtc-alm");
+	switch (mfd->chip_type) {
+	case ROHM_CHIP_TYPE_BD70528:
+		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;
+		break;
+	case ROHM_CHIP_TYPE_BD71828:
+		irq_name = "bd71828-rtc-alm-0";
+		bd_rtc->reg_time_start = BD71828_REG_RTC_START;
+		hour_reg = BD71828_REG_RTC_HOUR;
+		break;
+	default:
+		dev_err(&pdev->dev, "Unknown chip\n");
+		return -ENOENT;
+	}
+
+	irq = platform_get_irq_byname(pdev, irq_name);
 
 	if (irq < 0) {
 		dev_err(&pdev->dev, "Failed to get irq\n");
@@ -424,20 +592,20 @@ static int bd70528_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, bd_rtc);
 
-	ret = regmap_read(mfd->regmap, BD70528_REG_RTC_HOUR, &hr);
+	ret = regmap_read(mfd->regmap, hour_reg, &hr);
 
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to reag RTC clock\n");
 		return ret;
 	}
 
-	if (!(hr & BD70528_MASK_RTC_HOUR_24H)) {
+	if (!(hr & ROHM_BD1_MASK_RTC_HOUR_24H)) {
 		struct rtc_time t;
 
-		ret = bd70528_get_time(&pdev->dev, &t);
+		ret = bd7xx28_get_time(&pdev->dev, &t);
 
 		if (!ret)
-			ret = bd70528_set_time(&pdev->dev, &t);
+			ret = bd7xx28_set_time(&pdev->dev, &t);
 
 		if (ret) {
 			dev_err(&pdev->dev,
@@ -457,7 +625,7 @@ static int bd70528_probe(struct platform_device *pdev)
 
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
-	rtc->ops = &bd70528_rtc_ops;
+	rtc->ops = &bd7xx28_rtc_ops;
 
 	/* Request alarm IRQ prior to registerig the RTC */
 	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, &alm_hndlr,
@@ -471,12 +639,15 @@ static int bd70528_probe(struct platform_device *pdev)
 	 *  leave them enabled as irq-controller should disable irqs
 	 *  from sub-registers when IRQ is disabled or freed.
 	 */
-	ret = regmap_update_bits(mfd->regmap,
+	if (enable_main_irq) {
+		ret = regmap_update_bits(mfd->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;
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Failed to enable RTC interrupts\n");
+			return ret;
+		}
 	}
 
 	ret = rtc_register_device(rtc);
@@ -490,11 +661,11 @@ static struct platform_driver bd70528_rtc = {
 	.driver = {
 		.name = "bd70528-rtc"
 	},
-	.probe = bd70528_probe,
+	.probe = bd7xx28_probe,
 };
 
 module_platform_driver(bd70528_rtc);
 
 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
-MODULE_DESCRIPTION("BD70528 RTC driver");
+MODULE_DESCRIPTION("ROHM BD70528 and BD71828 PMIC RTC driver");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/rohm-bd70528.h b/include/linux/mfd/rohm-bd70528.h
index 1013e60c5b25..8d8c0e0b2df6 100644
--- a/include/linux/mfd/rohm-bd70528.h
+++ b/include/linux/mfd/rohm-bd70528.h
@@ -8,6 +8,7 @@
 #include <linux/device.h>
 #include <linux/mfd/rohm-generic.h>
 #include <linux/regmap.h>
+#include <linux/mfd/rohm-shared.h>
 
 enum {
 	BD70528_BUCK1,
@@ -313,16 +314,6 @@ enum {
 
 /* RTC masks to mask out reserved bits */
 
-#define BD70528_MASK_RTC_SEC		0x7f
-#define BD70528_MASK_RTC_MINUTE		0x7f
-#define BD70528_MASK_RTC_HOUR_24H	0x80
-#define BD70528_MASK_RTC_HOUR_PM	0x20
-#define BD70528_MASK_RTC_HOUR		0x1f
-#define BD70528_MASK_RTC_DAY		0x3f
-#define BD70528_MASK_RTC_WEEK		0x07
-#define BD70528_MASK_RTC_MONTH		0x1f
-#define BD70528_MASK_RTC_YEAR		0xff
-#define BD70528_MASK_RTC_COUNT_L	0x7f
 
 #define BD70528_MASK_ELAPSED_TIMER_EN	0x1
 /* Mask second, min and hour fields
@@ -332,7 +323,6 @@ enum {
  * wake-up we limit ALM to 24H and only
  * unmask sec, min and hour
  */
-#define BD70528_MASK_ALM_EN		0x7
 #define BD70528_MASK_WAKE_EN		0x1
 
 /* WDT masks */
diff --git a/include/linux/mfd/rohm-bd71828.h b/include/linux/mfd/rohm-bd71828.h
index bbbd4f118550..bd9dfd53759d 100644
--- a/include/linux/mfd/rohm-bd71828.h
+++ b/include/linux/mfd/rohm-bd71828.h
@@ -5,6 +5,7 @@
 #define __LINUX_MFD_BD71828_H__
 
 #include <linux/mfd/rohm-generic.h>
+#include <linux/mfd/rohm-shared.h>
 
 /* Regulator IDs */
 enum {
@@ -160,6 +161,7 @@ enum {
 #define BD71828_REG_RTC_YEAR		0x52
 
 #define BD71828_REG_RTC_ALM0_SEC	0x53
+#define BD71828_REG_RTC_ALM_START	BD71828_REG_RTC_ALM0_SEC
 #define BD71828_REG_RTC_ALM0_MINUTE	0x54
 #define BD71828_REG_RTC_ALM0_HOUR	0x55
 #define BD71828_REG_RTC_ALM0_WEEK	0x56
@@ -178,6 +180,7 @@ enum {
 #define BD71828_REG_RTC_ALM1_MASK	0x62
 
 #define BD71828_REG_RTC_ALM2		0x63
+#define BD71828_REG_RTC_START		BD71828_REG_RTC_SEC
 
 /* Charger/Battey */
 #define BD71828_REG_CHG_STATE		0x65
@@ -207,7 +210,6 @@ enum {
 #define BD71828_REG_INT_MASK_TEMP	0xdd
 #define BD71828_REG_INT_MASK_RTC	0xde
 
-
 #define BD71828_REG_INT_MAIN		0xdf
 #define BD71828_REG_INT_BUCK		0xe0
 #define BD71828_REG_INT_DCIN1		0xe1
diff --git a/include/linux/mfd/rohm-shared.h b/include/linux/mfd/rohm-shared.h
new file mode 100644
index 000000000000..5f61fa81d6a2
--- /dev/null
+++ b/include/linux/mfd/rohm-shared.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (C) 2018 ROHM Semiconductors */
+
+
+/*
+ * RTC definitions shared between
+ *
+ * BD70528
+ * and BD71828
+ */
+
+#define ROHM_BD1_MASK_RTC_SEC		0x7f
+#define ROHM_BD1_MASK_RTC_MINUTE	0x7f
+#define ROHM_BD1_MASK_RTC_HOUR_24H	0x80
+#define ROHM_BD1_MASK_RTC_HOUR_PM	0x20
+#define ROHM_BD1_MASK_RTC_HOUR		0x3f
+#define ROHM_BD1_MASK_RTC_DAY		0x3f
+#define ROHM_BD1_MASK_RTC_WEEK		0x07
+#define ROHM_BD1_MASK_RTC_MONTH		0x1f
+#define ROHM_BD1_MASK_RTC_YEAR		0xff
+#define ROHM_BD1_MASK_ALM_EN		0x7
+
-- 
2.21.0


-- 
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]