Merge tag 'rtc-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "RTC for 4.9

  Subsystem:
   - delete owner assignment in multiple drivers
   - constify rtc_class_ops structures

  Drivers:
   - ac100: support clock-output-names
   - cmos: properly handle ACPI alarms and quirky BIOSes and other fixes
   - ds1307: fix century bit support while staying comaptible with
     previous behaviour by default
   - ds1347: switch to regmap
   - isl12057 is now handled by ds1307
   - omap: support external wakeup
   - rv8803: allow to disable voltage drop detection"

* tag 'rtc-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (25 commits)
  rtc: rv8803: set VDETOFF and SWOFF via device tree
  dt/bindings: Add bindings for Micro Crystal rv8803
  devicetree: Add Micro Crystal AG vendor id
  rtc: cmos: avoid unused function warning
  rtc: ac100: Add NULL checking for devm_kzalloc call
  rtc: ds1347: changed raw spi calls to register map calls
  rtc: cmos: Restore alarm after resume
  rtc: cmos: Clear ACPI-driven alarms upon resume
  rtc: omap: Support ext_wakeup configuration
  rtc: cmos: Initialize hpet timer before irq is registered
  rtc: asm9260: rework locking
  rtc: asm9260: allow COMPILE_TEST
  rtc: constify rtc_class_ops structures
  rtc: ac100: support clock-output-names in device tree binding
  rtc: rx6110: remove owner assignment
  rtc: pic32: Delete owner assignment
  rtc: bq32k: Fix handling of oscillator failure flag
  rtc: bq32k: Use correct mask name for 'minutes' register.
  rtc: sysfs: fix a cast removing the const attribute
  Documentation: dt: Intersil isl12057 is not a trivial device
  ...

32 files changed, 453 insertions, 780 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index d1e080701264..e859d148aba9 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -208,14 +208,14 @@ config RTC_DRV_AS3722
 	  will be called rtc-as3722.
 
 config RTC_DRV_DS1307
-	tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00, EPSON RX-8025"
+	tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00, EPSON RX-8025, ISL12057"
 	help
 	  If you say yes here you get support for various compatible RTC
 	  chips (often with battery backup) connected with I2C. This driver
 	  should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
-	  EPSON RX-8025 and probably other chips. In some cases the RTC
-	  must already have been initialized (by manufacturing or a
-	  bootloader).
+	  EPSON RX-8025, Intersil ISL12057 and probably other chips. In some
+	  cases the RTC must already have been initialized (by manufacturing or
+	  a bootloader).
 
 	  The first seven registers on these chips hold an RTC, and other
 	  registers may add features such as NVRAM, a trickle charger for
@@ -234,6 +234,20 @@ config RTC_DRV_DS1307_HWMON
 	  Say Y here if you want to expose temperature sensor data on
 	  rtc-ds1307 (only DS3231)
 
+config RTC_DRV_DS1307_CENTURY
+	bool "Century bit support for rtc-ds1307"
+	depends on RTC_DRV_DS1307
+	default n
+	help
+	  The DS1307 driver suffered from a bug where it was enabling the
+	  century bit inconditionnally but never used it when reading the time.
+	  It made the driver unable to support dates beyond 2099.
+	  Setting this option will add proper support for the century bit but if
+	  the time was previously set using a kernel predating this option,
+	  reading the date will return a date in the next century.
+	  To solve that, you could boot a kernel without this option set, set
+	  the RTC date and then boot a kernel with this option set.
+
 config RTC_DRV_DS1374
 	tristate "Dallas/Maxim DS1374"
 	help
@@ -374,16 +388,6 @@ config RTC_DRV_ISL12022
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-isl12022.
 
-config RTC_DRV_ISL12057
-	select REGMAP_I2C
-	tristate "Intersil ISL12057"
-	help
-	  If you say yes here you get support for the Intersil ISL12057
-	  I2C RTC chip.
-
-	  This driver can also be built as a module. If so, the module
-	  will be called rtc-isl12057.
-
 config RTC_DRV_X1205
 	tristate "Xicor/Intersil X1205"
 	help
@@ -661,6 +665,7 @@ config RTC_DRV_DS1343
 	  will be called rtc-ds1343.
 
 config RTC_DRV_DS1347
+	select REGMAP_SPI
 	tristate "Dallas/Maxim DS1347"
 	help
 	  If you say yes here you get support for the
@@ -1201,7 +1206,7 @@ comment "on-CPU RTC drivers"
 
 config RTC_DRV_ASM9260
 	tristate "Alphascale asm9260 RTC"
-	depends on MACH_ASM9260
+	depends on MACH_ASM9260 || COMPILE_TEST
 	help
 	  If you say yes here you get support for the RTC on the
 	  Alphascale asm9260 SoC.
@@ -1241,6 +1246,9 @@ config RTC_DRV_IMXDI
 config RTC_DRV_OMAP
 	tristate "TI OMAP Real Time Clock"
 	depends on ARCH_OMAP || ARCH_DAVINCI || COMPILE_TEST
+	depends on OF
+	depends on PINCTRL
+	select GENERIC_PINCONF
 	help
 	  Say "yes" here to support the on chip real time clock
 	  present on TI OMAP1, AM33xx, DA8xx/OMAP-L13x, AM43xx and DRA7xx.
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 8fb994bacdf7..1ac694a330c8 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -72,7 +72,6 @@ obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o
 obj-$(CONFIG_RTC_DRV_HYM8563)	+= rtc-hym8563.o
 obj-$(CONFIG_RTC_DRV_IMXDI)	+= rtc-imxdi.o
 obj-$(CONFIG_RTC_DRV_ISL12022)	+= rtc-isl12022.o
-obj-$(CONFIG_RTC_DRV_ISL12057)	+= rtc-isl12057.o
 obj-$(CONFIG_RTC_DRV_ISL1208)	+= rtc-isl1208.o
 obj-$(CONFIG_RTC_DRV_JZ4740)	+= rtc-jz4740.o
 obj-$(CONFIG_RTC_DRV_LP8788)	+= rtc-lp8788.o
diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c
index 70b4fd0f6122..9e336184491c 100644
--- a/drivers/rtc/rtc-ac100.c
+++ b/drivers/rtc/rtc-ac100.c
@@ -327,6 +327,8 @@ static int ac100_rtc_register_clks(struct ac100_rtc_dev *chip)
 			.flags = 0,
 		};
 
+		of_property_read_string_index(np, "clock-output-names",
+					      i, &init.name);
 		clk->regmap = chip->regmap;
 		clk->offset = AC100_CLKOUT_CTRL1 + i;
 		clk->hw.init = &init;
@@ -552,6 +554,9 @@ static int ac100_rtc_probe(struct platform_device *pdev)
 	int ret;
 
 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
 	platform_set_drvdata(pdev, chip);
 	chip->dev = &pdev->dev;
 	chip->regmap = ac100->regmap;
diff --git a/drivers/rtc/rtc-asm9260.c b/drivers/rtc/rtc-asm9260.c
index 5219916ce11d..18a93d3e3f93 100644
--- a/drivers/rtc/rtc-asm9260.c
+++ b/drivers/rtc/rtc-asm9260.c
@@ -112,8 +112,6 @@ struct asm9260_rtc_priv {
 	void __iomem		*iobase;
 	struct rtc_device	*rtc;
 	struct clk		*clk;
-	/* io lock */
-	spinlock_t		lock;
 };
 
 static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
@@ -122,11 +120,15 @@ static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
 	u32 isr;
 	unsigned long events = 0;
 
+	mutex_lock(&priv->rtc->ops_lock);
 	isr = ioread32(priv->iobase + HW_CIIR);
-	if (!isr)
+	if (!isr) {
+		mutex_unlock(&priv->rtc->ops_lock);
 		return IRQ_NONE;
+	}
 
 	iowrite32(0, priv->iobase + HW_CIIR);
+	mutex_unlock(&priv->rtc->ops_lock);
 
 	events |= RTC_AF | RTC_IRQF;
 
@@ -139,9 +141,7 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
 	u32 ctime0, ctime1, ctime2;
-	unsigned long irq_flags;
 
-	spin_lock_irqsave(&priv->lock, irq_flags);
 	ctime0 = ioread32(priv->iobase + HW_CTIME0);
 	ctime1 = ioread32(priv->iobase + HW_CTIME1);
 	ctime2 = ioread32(priv->iobase + HW_CTIME2);
@@ -155,7 +155,6 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
 		ctime1 = ioread32(priv->iobase + HW_CTIME1);
 		ctime2 = ioread32(priv->iobase + HW_CTIME2);
 	}
-	spin_unlock_irqrestore(&priv->lock, irq_flags);
 
 	tm->tm_sec  = (ctime0 >> BM_CTIME0_SEC_S)  & BM_CTIME0_SEC_M;
 	tm->tm_min  = (ctime0 >> BM_CTIME0_MIN_S)  & BM_CTIME0_MIN_M;
@@ -174,9 +173,7 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
 static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
-	unsigned long irq_flags;
 
-	spin_lock_irqsave(&priv->lock, irq_flags);
 	/*
 	 * make sure SEC counter will not flip other counter on write time,
 	 * real value will be written at the enf of sequence.
@@ -191,7 +188,6 @@ static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	iowrite32(tm->tm_hour, priv->iobase + HW_HOUR);
 	iowrite32(tm->tm_min,  priv->iobase + HW_MIN);
 	iowrite32(tm->tm_sec,  priv->iobase + HW_SEC);
-	spin_unlock_irqrestore(&priv->lock, irq_flags);
 
 	return 0;
 }
@@ -199,9 +195,7 @@ static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
 static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
-	unsigned long irq_flags;
 
-	spin_lock_irqsave(&priv->lock, irq_flags);
 	alrm->time.tm_year = ioread32(priv->iobase + HW_ALYEAR);
 	alrm->time.tm_mon  = ioread32(priv->iobase + HW_ALMON);
 	alrm->time.tm_mday = ioread32(priv->iobase + HW_ALDOM);
@@ -213,7 +207,6 @@ static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 
 	alrm->enabled = ioread32(priv->iobase + HW_AMR) ? 1 : 0;
 	alrm->pending = ioread32(priv->iobase + HW_CIIR) ? 1 : 0;
-	spin_unlock_irqrestore(&priv->lock, irq_flags);
 
 	return rtc_valid_tm(&alrm->time);
 }
@@ -221,9 +214,7 @@ static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
-	unsigned long irq_flags;
 
-	spin_lock_irqsave(&priv->lock, irq_flags);
 	iowrite32(alrm->time.tm_year, priv->iobase + HW_ALYEAR);
 	iowrite32(alrm->time.tm_mon,  priv->iobase + HW_ALMON);
 	iowrite32(alrm->time.tm_mday, priv->iobase + HW_ALDOM);
@@ -234,7 +225,6 @@ static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	iowrite32(alrm->time.tm_sec,  priv->iobase + HW_ALSEC);
 
 	iowrite32(alrm->enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
-	spin_unlock_irqrestore(&priv->lock, irq_flags);
 
 	return 0;
 }
diff --git a/drivers/rtc/rtc-at32ap700x.c b/drivers/rtc/rtc-at32ap700x.c
index 83ac2337c0f7..de8bf56a41e7 100644
--- a/drivers/rtc/rtc-at32ap700x.c
+++ b/drivers/rtc/rtc-at32ap700x.c
@@ -187,7 +187,7 @@ static irqreturn_t at32_rtc_interrupt(int irq, void *dev_id)
 	return ret;
 }
 
-static struct rtc_class_ops at32_rtc_ops = {
+static const struct rtc_class_ops at32_rtc_ops = {
 	.read_time	= at32_rtc_readtime,
 	.set_time	= at32_rtc_settime,
 	.read_alarm	= at32_rtc_readalarm,
diff --git a/drivers/rtc/rtc-bq32k.c b/drivers/rtc/rtc-bq32k.c
index 0299988b4f13..397742446007 100644
--- a/drivers/rtc/rtc-bq32k.c
+++ b/drivers/rtc/rtc-bq32k.c
@@ -93,8 +93,15 @@ static int bq32k_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	if (error)
 		return error;
 
+	/*
+	 * In case of oscillator failure, the register contents should be
+	 * considered invalid. The flag is cleared the next time the RTC is set.
+	 */
+	if (regs.minutes & BQ32K_OF)
+		return -EINVAL;
+
 	tm->tm_sec = bcd2bin(regs.seconds & BQ32K_SECONDS_MASK);
-	tm->tm_min = bcd2bin(regs.minutes & BQ32K_SECONDS_MASK);
+	tm->tm_min = bcd2bin(regs.minutes & BQ32K_MINUTES_MASK);
 	tm->tm_hour = bcd2bin(regs.cent_hours & BQ32K_HOURS_MASK);
 	tm->tm_mday = bcd2bin(regs.date);
 	tm->tm_wday = bcd2bin(regs.day) - 1;
@@ -204,13 +211,10 @@ static int bq32k_probe(struct i2c_client *client,
 
 	/* Check Oscillator Failure flag */
 	error = bq32k_read(dev, &reg, BQ32K_MINUTES, 1);
-	if (!error && (reg & BQ32K_OF)) {
-		dev_warn(dev, "Oscillator Failure. Check RTC battery.\n");
-		reg &= ~BQ32K_OF;
-		error = bq32k_write(dev, &reg, BQ32K_MINUTES, 1);
-	}
 	if (error)
 		return error;
+	if (reg & BQ32K_OF)
+		dev_warn(dev, "Oscillator Failure. Check RTC battery.\n");
 
 	if (client->dev.of_node)
 		trickle_charger_of_init(dev, client->dev.of_node);
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 43745cac0141..dd3d59806ffa 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -62,6 +62,8 @@ struct cmos_rtc {
 	u8			day_alrm;
 	u8			mon_alrm;
 	u8			century;
+
+	struct rtc_wkalrm	saved_wkalrm;
 };
 
 /* both platform and pnp busses use negative numbers for invalid irqs */
@@ -707,6 +709,8 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 		goto cleanup1;
 	}
 
+	hpet_rtc_timer_init();
+
 	if (is_valid_irq(rtc_irq)) {
 		irq_handler_t rtc_cmos_int_handler;
 
@@ -714,6 +718,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 			rtc_cmos_int_handler = hpet_rtc_interrupt;
 			retval = hpet_register_irq_handler(cmos_interrupt);
 			if (retval) {
+				hpet_mask_rtc_irq_bit(RTC_IRQMASK);
 				dev_warn(dev, "hpet_register_irq_handler "
 						" failed in rtc_init().");
 				goto cleanup1;
@@ -729,7 +734,6 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 			goto cleanup1;
 		}
 	}
-	hpet_rtc_timer_init();
 
 	/* export at least the first block of NVRAM */
 	nvram.size = address_space - NVRAM_OFFSET;
@@ -844,8 +848,6 @@ static int cmos_aie_poweroff(struct device *dev)
 	return retval;
 }
 
-#ifdef CONFIG_PM
-
 static int cmos_suspend(struct device *dev)
 {
 	struct cmos_rtc	*cmos = dev_get_drvdata(dev);
@@ -877,6 +879,8 @@ static int cmos_suspend(struct device *dev)
 			enable_irq_wake(cmos->irq);
 	}
 
+	cmos_read_alarm(dev, &cmos->saved_wkalrm);
+
 	dev_dbg(dev, "suspend%s, ctrl %02x\n",
 			(tmp & RTC_AIE) ? ", alarm may wake" : "",
 			tmp);
@@ -892,12 +896,32 @@ static int cmos_suspend(struct device *dev)
  */
 static inline int cmos_poweroff(struct device *dev)
 {
+	if (!IS_ENABLED(CONFIG_PM))
+		return -ENOSYS;
+
 	return cmos_suspend(dev);
 }
 
-#ifdef	CONFIG_PM_SLEEP
+static void cmos_check_wkalrm(struct device *dev)
+{
+	struct cmos_rtc *cmos = dev_get_drvdata(dev);
+	struct rtc_wkalrm current_alarm;
+	time64_t t_current_expires;
+	time64_t t_saved_expires;
+
+	cmos_read_alarm(dev, &current_alarm);
+	t_current_expires = rtc_tm_to_time64(&current_alarm.time);
+	t_saved_expires = rtc_tm_to_time64(&cmos->saved_wkalrm.time);
+	if (t_current_expires != t_saved_expires ||
+	    cmos->saved_wkalrm.enabled != current_alarm.enabled) {
+		cmos_set_alarm(dev, &cmos->saved_wkalrm);
+	}
+}
+
+static void cmos_check_acpi_rtc_status(struct device *dev,
+				       unsigned char *rtc_control);
 
-static int cmos_resume(struct device *dev)
+static int __maybe_unused cmos_resume(struct device *dev)
 {
 	struct cmos_rtc	*cmos = dev_get_drvdata(dev);
 	unsigned char tmp;
@@ -910,6 +934,9 @@ static int cmos_resume(struct device *dev)
 		cmos->enabled_wake = 0;
 	}
 
+	/* The BIOS might have changed the alarm, restore it */
+	cmos_check_wkalrm(dev);
+
 	spin_lock_irq(&rtc_lock);
 	tmp = cmos->suspend_ctrl;
 	cmos->suspend_ctrl = 0;
@@ -936,6 +963,9 @@ static int cmos_resume(struct device *dev)
 			tmp &= ~RTC_AIE;
 			hpet_mask_rtc_irq_bit(RTC_AIE);
 		} while (mask & RTC_AIE);
+
+		if (tmp & RTC_AIE)
+			cmos_check_acpi_rtc_status(dev, &tmp);
 	}
 	spin_unlock_irq(&rtc_lock);
 
@@ -944,16 +974,6 @@ static int cmos_resume(struct device *dev)
 	return 0;
 }
 
-#endif
-#else
-
-static inline int cmos_poweroff(struct device *dev)
-{
-	return -ENOSYS;
-}
-
-#endif
-
 static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
 
 /*----------------------------------------------------------------*/
@@ -973,6 +993,20 @@ static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
 static u32 rtc_handler(void *context)
 {
 	struct device *dev = context;
+	struct cmos_rtc *cmos = dev_get_drvdata(dev);
+	unsigned char rtc_control = 0;
+	unsigned char rtc_intr;
+
+	spin_lock_irq(&rtc_lock);
+	if (cmos_rtc.suspend_ctrl)
+		rtc_control = CMOS_READ(RTC_CONTROL);
+	if (rtc_control & RTC_AIE) {
+		cmos_rtc.suspend_ctrl &= ~RTC_AIE;
+		CMOS_WRITE(rtc_control, RTC_CONTROL);
+		rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
+		rtc_update_irq(cmos->rtc, 1, rtc_intr);
+	}
+	spin_unlock_irq(&rtc_lock);
 
 	pm_wakeup_event(dev, 0);
 	acpi_clear_event(ACPI_EVENT_RTC);
@@ -1039,12 +1073,39 @@ static void cmos_wake_setup(struct device *dev)
 	device_init_wakeup(dev, 1);
 }
 
+static void cmos_check_acpi_rtc_status(struct device *dev,
+				       unsigned char *rtc_control)
+{
+	struct cmos_rtc *cmos = dev_get_drvdata(dev);
+	acpi_event_status rtc_status;
+	acpi_status status;
+
+	if (acpi_gbl_FADT.flags & ACPI_FADT_FIXED_RTC)
+		return;
+
+	status = acpi_get_event_status(ACPI_EVENT_RTC, &rtc_status);
+	if (ACPI_FAILURE(status)) {
+		dev_err(dev, "Could not get RTC status\n");
+	} else if (rtc_status & ACPI_EVENT_FLAG_SET) {
+		unsigned char mask;
+		*rtc_control &= ~RTC_AIE;
+		CMOS_WRITE(*rtc_control, RTC_CONTROL);
+		mask = CMOS_READ(RTC_INTR_FLAGS);
+		rtc_update_irq(cmos->rtc, 1, mask);
+	}
+}
+
 #else
 
 static void cmos_wake_setup(struct device *dev)
 {
 }
 
+static void cmos_check_acpi_rtc_status(struct device *dev,
+				       unsigned char *rtc_control)
+{
+}
+
 #endif
 
 #ifdef	CONFIG_PNP
@@ -1206,9 +1267,7 @@ static struct platform_driver cmos_platform_driver = {
 	.shutdown	= cmos_platform_shutdown,
 	.driver = {
 		.name		= driver_name,
-#ifdef CONFIG_PM
 		.pm		= &cmos_pm_ops,
-#endif
 		.of_match_table = of_match_ptr(of_cmos_match),
 	}
 };
diff --git a/drivers/rtc/rtc-coh901331.c b/drivers/rtc/rtc-coh901331.c
index 101b7a240e0f..cfc4141d99cd 100644
--- a/drivers/rtc/rtc-coh901331.c
+++ b/drivers/rtc/rtc-coh901331.c
@@ -140,7 +140,7 @@ static int coh901331_alarm_irq_enable(struct device *dev, unsigned int enabled)
 	return 0;
 }
 
-static struct rtc_class_ops coh901331_ops = {
+static const struct rtc_class_ops coh901331_ops = {
 	.read_time = coh901331_read_time,
 	.set_mmss = coh901331_set_mmss,
 	.read_alarm = coh901331_read_alarm,
diff --git a/drivers/rtc/rtc-davinci.c b/drivers/rtc/rtc-davinci.c
index dba60c1dfce2..caf35567e14c 100644
--- a/drivers/rtc/rtc-davinci.c
+++ b/drivers/rtc/rtc-davinci.c
@@ -469,7 +469,7 @@ static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	return 0;
 }
 
-static struct rtc_class_ops davinci_rtc_ops = {
+static const struct rtc_class_ops davinci_rtc_ops = {
 	.ioctl			= davinci_rtc_ioctl,
 	.read_time		= davinci_rtc_read_time,
 	.set_time		= davinci_rtc_set_time,
diff --git a/drivers/rtc/rtc-digicolor.c b/drivers/rtc/rtc-digicolor.c
index 8d05596a6765..b253bf1b3531 100644
--- a/drivers/rtc/rtc-digicolor.c
+++ b/drivers/rtc/rtc-digicolor.c
@@ -159,7 +159,7 @@ static int dc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 	return 0;
 }
 
-static struct rtc_class_ops dc_rtc_ops = {
+static const struct rtc_class_ops dc_rtc_ops = {
 	.read_time		= dc_rtc_read_time,
 	.set_mmss		= dc_rtc_set_mmss,
 	.read_alarm		= dc_rtc_read_alarm,
diff --git a/drivers/rtc/rtc-ds1302.c b/drivers/rtc/rtc-ds1302.c
index f5dd09fe5add..0ec4be62322b 100644
--- a/drivers/rtc/rtc-ds1302.c
+++ b/drivers/rtc/rtc-ds1302.c
@@ -102,7 +102,7 @@ static int ds1302_rtc_get_time(struct device *dev, struct rtc_time *time)
 	return rtc_valid_tm(time);
 }
 
-static struct rtc_class_ops ds1302_rtc_ops = {
+static const struct rtc_class_ops ds1302_rtc_ops = {
 	.read_time	= ds1302_rtc_get_time,
 	.set_time	= ds1302_rtc_set_time,
 };
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 8e1c5cb6ece6..4e31036ee259 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -186,6 +186,7 @@ static const struct i2c_device_id ds1307_id[] = {
 	{ "mcp7941x", mcp794xx },
 	{ "pt7c4338", ds_1307 },
 	{ "rx8025", rx_8025 },
+	{ "isl12057", ds_1337 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ds1307_id);
@@ -382,10 +383,25 @@ static int ds1307_get_time(struct device *dev, struct rtc_time *t)
 	t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
 	tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;
 	t->tm_mon = bcd2bin(tmp) - 1;
-
-	/* assume 20YY not 19YY, and ignore DS1337_BIT_CENTURY */
 	t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_YEAR]) + 100;
 
+#ifdef CONFIG_RTC_DRV_DS1307_CENTURY
+	switch (ds1307->type) {
+	case ds_1337:
+	case ds_1339:
+	case ds_3231:
+		if (ds1307->regs[DS1307_REG_MONTH] & DS1337_BIT_CENTURY)
+			t->tm_year += 100;
+		break;
+	case ds_1340:
+		if (ds1307->regs[DS1307_REG_HOUR] & DS1340_BIT_CENTURY)
+			t->tm_year += 100;
+		break;
+	default:
+		break;
+	}
+#endif
+
 	dev_dbg(dev, "%s secs=%d, mins=%d, "
 		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 		"read", t->tm_sec, t->tm_min,
@@ -409,6 +425,27 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t)
 		t->tm_hour, t->tm_mday,
 		t->tm_mon, t->tm_year, t->tm_wday);
 
+#ifdef CONFIG_RTC_DRV_DS1307_CENTURY
+	if (t->tm_year < 100)
+		return -EINVAL;
+
+	switch (ds1307->type) {
+	case ds_1337:
+	case ds_1339:
+	case ds_3231:
+	case ds_1340:
+		if (t->tm_year > 299)
+			return -EINVAL;
+	default:
+		if (t->tm_year > 199)
+			return -EINVAL;
+		break;
+	}
+#else
+	if (t->tm_year < 100 || t->tm_year > 199)
+		return -EINVAL;
+#endif
+
 	buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
 	buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);
 	buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
@@ -424,11 +461,13 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t)
 	case ds_1337:
 	case ds_1339:
 	case ds_3231:
-		buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
+		if (t->tm_year > 199)
+			buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
 		break;
 	case ds_1340:
-		buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
-				| DS1340_BIT_CENTURY;
+		buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN;
+		if (t->tm_year > 199)
+			buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY;
 		break;
 	case mcp794xx:
 		/*
@@ -1295,6 +1334,11 @@ static int ds1307_probe(struct i2c_client *client,
 	if (of_property_read_bool(client->dev.of_node, "wakeup-source")) {
 		ds1307_can_wakeup_device = true;
 	}
+	/* Intersil ISL12057 DT backward compatibility */
+	if (of_property_read_bool(client->dev.of_node,
+				  "isil,irq2-can-wakeup-machine")) {
+		ds1307_can_wakeup_device = true;
+	}
 #endif
 
 	switch (ds1307->type) {
diff --git a/drivers/rtc/rtc-ds1347.c b/drivers/rtc/rtc-ds1347.c
index 641e8e8a0dd7..ccfc9d43eb1e 100644
--- a/drivers/rtc/rtc-ds1347.c
+++ b/drivers/rtc/rtc-ds1347.c
@@ -18,6 +18,7 @@
 #include <linux/rtc.h>
 #include <linux/spi/spi.h>
 #include <linux/bcd.h>
+#include <linux/regmap.h>
 
 /* Registers in ds1347 rtc */
 
@@ -32,37 +33,28 @@
 #define DS1347_STATUS_REG	0x17
 #define DS1347_CLOCK_BURST	0x3F
 
-static int ds1347_read_reg(struct device *dev, unsigned char address,
-				unsigned char *data)
-{
-	struct spi_device *spi = to_spi_device(dev);
-
-	*data = address | 0x80;
-
-	return spi_write_then_read(spi, data, 1, data, 1);
-}
-
-static int ds1347_write_reg(struct device *dev, unsigned char address,
-				unsigned char data)
-{
-	struct spi_device *spi = to_spi_device(dev);
-	unsigned char buf[2];
-
-	buf[0] = address & 0x7F;
-	buf[1] = data;
+static const struct regmap_range ds1347_ranges[] = {
+	{
+		.range_min = DS1347_SECONDS_REG,
+		.range_max = DS1347_STATUS_REG,
+	},
+};
 
-	return spi_write_then_read(spi, buf, 2, NULL, 0);
-}
+static const struct regmap_access_table ds1347_access_table = {
+	.yes_ranges = ds1347_ranges,
+	.n_yes_ranges = ARRAY_SIZE(ds1347_ranges),
+};
 
 static int ds1347_read_time(struct device *dev, struct rtc_time *dt)
 {
 	struct spi_device *spi = to_spi_device(dev);
+	struct regmap *map;
 	int err;
 	unsigned char buf[8];
 
-	buf[0] = DS1347_CLOCK_BURST | 0x80;
+	map = spi_get_drvdata(spi);
 
-	err = spi_write_then_read(spi, buf, 1, buf, 8);
+	err = regmap_bulk_read(map, DS1347_CLOCK_BURST, buf, 8);
 	if (err)
 		return err;
 
@@ -80,25 +72,27 @@ static int ds1347_read_time(struct device *dev, struct rtc_time *dt)
 static int ds1347_set_time(struct device *dev, struct rtc_time *dt)
 {
 	struct spi_device *spi = to_spi_device(dev);
-	unsigned char buf[9];
+	struct regmap *map;
+	unsigned char buf[8];
+
+	map = spi_get_drvdata(spi);
 
-	buf[0] = DS1347_CLOCK_BURST & 0x7F;
-	buf[1] = bin2bcd(dt->tm_sec);
-	buf[2] = bin2bcd(dt->tm_min);
-	buf[3] = (bin2bcd(dt->tm_hour) & 0x3F);
-	buf[4] = bin2bcd(dt->tm_mday);
-	buf[5] = bin2bcd(dt->tm_mon + 1);
-	buf[6] = bin2bcd(dt->tm_wday + 1);
+	buf[0] = bin2bcd(dt->tm_sec);
+	buf[1] = bin2bcd(dt->tm_min);
+	buf[2] = (bin2bcd(dt->tm_hour) & 0x3F);
+	buf[3] = bin2bcd(dt->tm_mday);
+	buf[4] = bin2bcd(dt->tm_mon + 1);
+	buf[5] = bin2bcd(dt->tm_wday + 1);
 
 	/* year in linux is from 1900 i.e in range of 100
 	in rtc it is from 00 to 99 */
 	dt->tm_year = dt->tm_year % 100;
 
-	buf[7] = bin2bcd(dt->tm_year);
-	buf[8] = bin2bcd(0x00);
+	buf[6] = bin2bcd(dt->tm_year);
+	buf[7] = bin2bcd(0x00);
 
 	/* write the rtc settings */
-	return spi_write_then_read(spi, buf, 9, NULL, 0);
+	return regmap_bulk_write(map, DS1347_CLOCK_BURST, buf, 8);
 }
 
 static const struct rtc_class_ops ds1347_rtc_ops = {
@@ -109,35 +103,53 @@ static const struct rtc_class_ops ds1347_rtc_ops = {
 static int ds1347_probe(struct spi_device *spi)
 {
 	struct rtc_device *rtc;
-	unsigned char data;
+	struct regmap_config config;
+	struct regmap *map;
+	unsigned int data;
 	int res;
 
+	memset(&config, 0, sizeof(config));
+	config.reg_bits = 8;
+	config.val_bits = 8;
+	config.read_flag_mask = 0x80;
+	config.max_register = 0x3F;
+	config.wr_table = &ds1347_access_table;
+
 	/* spi setup with ds1347 in mode 3 and bits per word as 8 */
 	spi->mode = SPI_MODE_3;
 	spi->bits_per_word = 8;
 	spi_setup(spi);
 
+	map = devm_regmap_init_spi(spi, &config);
+
+	if (IS_ERR(map)) {
+		dev_err(&spi->dev, "ds1347 regmap init spi failed\n");
+		return PTR_ERR(map);
+	}
+
+	spi_set_drvdata(spi, map);
+
 	/* RTC Settings */
-	res = ds1347_read_reg(&spi->dev, DS1347_SECONDS_REG, &data);
+	res = regmap_read(map, DS1347_SECONDS_REG, &data);
 	if (res)
 		return res;
 
 	/* Disable the write protect of rtc */
-	ds1347_read_reg(&spi->dev, DS1347_CONTROL_REG, &data);
+	regmap_read(map, DS1347_CONTROL_REG, &data);
 	data = data & ~(1<<7);
-	ds1347_write_reg(&spi->dev, DS1347_CONTROL_REG, data);
+	regmap_write(map, DS1347_CONTROL_REG, data);
 
 	/* Enable the oscillator , disable the oscillator stop flag,
 	 and glitch filter to reduce current consumption */
-	ds1347_read_reg(&spi->dev, DS1347_STATUS_REG, &data);
+	regmap_read(map, DS1347_STATUS_REG, &data);
 	data = data & 0x1B;
-	ds1347_write_reg(&spi->dev, DS1347_STATUS_REG, data);
+	regmap_write(map, DS1347_STATUS_REG, data);
 
 	/* display the settings */
-	ds1347_read_reg(&spi->dev, DS1347_CONTROL_REG, &data);
+	regmap_read(map, DS1347_CONTROL_REG, &data);
 	dev_