Merge tag 'rtc-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "There are three new drivers this cycle. Also the cmos driver is
  getting fixes for longstanding wakeup issues on AMD.

  New drivers:
   - Analog Devices MAX31335
   - Nuvoton ma35d1
   - Texas Instrument TPS6594 PMIC RTC

  Drivers:
   - cmos: use ACPI alarm instead of HPET on recent AMD platforms
   - nuvoton: add NCT3015Y-R and NCT3018Y-R support
   - rv8803: proper suspend/resume and wakeup-source support"

* tag 'rtc-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (26 commits)
  rtc: nuvoton: Compatible with NCT3015Y-R and NCT3018Y-R
  rtc: da9063: Use dev_err_probe()
  rtc: da9063: Use device_get_match_data()
  rtc: da9063: Make IRQ as optional
  rtc: max31335: Fix comparison in max31335_volatile_reg()
  rtc: max31335: use regmap_update_bits_check
  rtc: max31335: remove unecessary locking
  rtc: max31335: add driver support
  dt-bindings: rtc: max31335: add max31335 bindings
  rtc: rv8803: add wakeup-source support
  rtc: ac100: remove misuses of kernel-doc
  rtc: class: Remove usage of the deprecated ida_simple_xx() API
  rtc: MAINTAINERS: drop Alessandro Zummo
  rtc: ma35d1: remove hardcoded UIE support
  dt-bindings: rtc: qcom-pm8xxx: fix inconsistent example
  rtc: rv8803: Add power management support
  rtc: ds3232: avoid unused-const-variable warning
  rtc: lpc24xx: add missing dependency
  rtc: tps6594: Add driver for TPS6594 RTC
  rtc: Add driver for Nuvoton ma35d1 rtc controller
  ...

14 files changed, 1668 insertions, 82 deletions

diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index 72b7a92337b1..cd6e559648b2 100644
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c
@@ -120,7 +120,7 @@ static unsigned int read_magic_time(void)
 	struct rtc_time time;
 	unsigned int val;
 
-	if (mc146818_get_time(&time) < 0) {
+	if (mc146818_get_time(&time, 1000) < 0) {
 		pr_err("Unable to read current time from RTC\n");
 		return 0;
 	}
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 3814e0845e77..e37a4341f442 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -373,6 +373,19 @@ config RTC_DRV_MAX8997
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-max8997.
 
+config RTC_DRV_MAX31335
+	tristate "Analog Devices MAX31335"
+	depends on I2C
+	depends on COMMON_CLK
+	depends on HWMON || HWMON=n
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the Analog Devices
+	  MAX31335.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-max31335.
+
 config RTC_DRV_MAX77686
 	tristate "Maxim MAX77686"
 	depends on MFD_MAX77686 || MFD_MAX77620 || MFD_MAX77714 || COMPILE_TEST
@@ -578,6 +591,18 @@ config RTC_DRV_TPS6586X
 	  along with alarm. This driver supports the RTC driver for
 	  the TPS6586X RTC module.
 
+config RTC_DRV_TPS6594
+	tristate "TI TPS6594 RTC driver"
+	depends on MFD_TPS6594
+	default MFD_TPS6594
+	help
+	  TI Power Management IC TPS6594 supports RTC functionality
+	  along with alarm. This driver supports the RTC driver for
+	  the TPS6594 RTC module.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-tps6594.
+
 config RTC_DRV_TPS65910
 	tristate "TI TPS65910 RTC driver"
 	depends on MFD_TPS65910
@@ -1705,6 +1730,7 @@ config RTC_DRV_LPC24XX
 	tristate "NXP RTC for LPC178x/18xx/408x/43xx"
 	depends on ARCH_LPC18XX || COMPILE_TEST
 	depends on OF && HAS_IOMEM
+	depends on COMMON_CLK
 	help
 	  This enables support for the NXP RTC found which can be found on
 	  NXP LPC178x/18xx/408x/43xx devices.
@@ -1930,6 +1956,17 @@ config RTC_DRV_TI_K3
 	  This driver can also be built as a module, if so, the module
 	  will be called "rtc-ti-k3".
 
+config RTC_DRV_MA35D1
+	tristate "Nuvoton MA35D1 RTC"
+	depends on ARCH_MA35 || COMPILE_TEST
+	select REGMAP_MMIO
+	help
+	   If you say yes here you get support for the Nuvoton MA35D1
+	   On-Chip Real Time Clock.
+
+	   This driver can also be built as a module, if so, the module
+	   will be called "rtc-ma35d1".
+
 comment "HID Sensor RTC drivers"
 
 config RTC_DRV_HID_SENSOR_TIME
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 7b03c3abfd78..6efff381c484 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -88,6 +88,8 @@ obj-$(CONFIG_RTC_DRV_M41T94)	+= rtc-m41t94.o
 obj-$(CONFIG_RTC_DRV_M48T35)	+= rtc-m48t35.o
 obj-$(CONFIG_RTC_DRV_M48T59)	+= rtc-m48t59.o
 obj-$(CONFIG_RTC_DRV_M48T86)	+= rtc-m48t86.o
+obj-$(CONFIG_RTC_DRV_MA35D1)	+= rtc-ma35d1.o
+obj-$(CONFIG_RTC_DRV_MAX31335)	+= rtc-max31335.o
 obj-$(CONFIG_RTC_DRV_MAX6900)	+= rtc-max6900.o
 obj-$(CONFIG_RTC_DRV_MAX6902)	+= rtc-max6902.o
 obj-$(CONFIG_RTC_DRV_MAX6916)	+= rtc-max6916.o
@@ -176,6 +178,7 @@ obj-$(CONFIG_RTC_DRV_TEGRA)	+= rtc-tegra.o
 obj-$(CONFIG_RTC_DRV_TEST)	+= rtc-test.o
 obj-$(CONFIG_RTC_DRV_TI_K3)	+= rtc-ti-k3.o
 obj-$(CONFIG_RTC_DRV_TPS6586X)	+= rtc-tps6586x.o
+obj-$(CONFIG_RTC_DRV_TPS6594)	+= rtc-tps6594.o
 obj-$(CONFIG_RTC_DRV_TPS65910)	+= rtc-tps65910.o
 obj-$(CONFIG_RTC_DRV_TWL4030)	+= rtc-twl.o
 obj-$(CONFIG_RTC_DRV_VT8500)	+= rtc-vt8500.o
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index edfd942f8c54..921ee1827974 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -256,7 +256,7 @@ static int rtc_device_get_id(struct device *dev)
 		of_id = of_alias_get_id(dev->parent->of_node, "rtc");
 
 	if (of_id >= 0) {
-		id = ida_simple_get(&rtc_ida, of_id, of_id + 1, GFP_KERNEL);
+		id = ida_alloc_range(&rtc_ida, of_id, of_id, GFP_KERNEL);
 		if (id < 0)
 			dev_warn(dev, "/aliases ID %d not available\n", of_id);
 	}
diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c
index eaf2c9ab9661..fa642bba3cee 100644
--- a/drivers/rtc/rtc-ac100.c
+++ b/drivers/rtc/rtc-ac100.c
@@ -99,7 +99,7 @@ struct ac100_rtc_dev {
 	struct clk_hw_onecell_data *clk_data;
 };
 
-/**
+/*
  * Clock controls for 3 clock output pins
  */
 
@@ -378,7 +378,7 @@ static void ac100_rtc_unregister_clks(struct ac100_rtc_dev *chip)
 	clk_unregister_fixed_rate(chip->rtc_32k_clk->clk);
 }
 
-/**
+/*
  * RTC related bits
  */
 static int ac100_rtc_get_time(struct device *dev, struct rtc_time *rtc_tm)
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 228fb2d11c70..7d99cd2c37a0 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -231,7 +231,7 @@ static int cmos_read_time(struct device *dev, struct rtc_time *t)
 	if (!pm_trace_rtc_valid())
 		return -EIO;
 
-	ret = mc146818_get_time(t);
+	ret = mc146818_get_time(t, 1000);
 	if (ret < 0) {
 		dev_err_ratelimited(dev, "unable to read current time\n");
 		return ret;
@@ -292,7 +292,7 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 
 	/* This not only a rtc_op, but also called directly */
 	if (!is_valid_irq(cmos->irq))
-		return -EIO;
+		return -ETIMEDOUT;
 
 	/* Basic alarms only support hour, minute, and seconds fields.
 	 * Some also support day and month, for alarms up to a year in
@@ -307,7 +307,7 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 	 *
 	 * Use the mc146818_avoid_UIP() function to avoid this.
 	 */
-	if (!mc146818_avoid_UIP(cmos_read_alarm_callback, &p))
+	if (!mc146818_avoid_UIP(cmos_read_alarm_callback, 10, &p))
 		return -EIO;
 
 	if (!(p.rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
@@ -556,8 +556,8 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 	 *
 	 * Use mc146818_avoid_UIP() to avoid this.
 	 */
-	if (!mc146818_avoid_UIP(cmos_set_alarm_callback, &p))
-		return -EIO;
+	if (!mc146818_avoid_UIP(cmos_set_alarm_callback, 10, &p))
+		return -ETIMEDOUT;
 
 	cmos->alarm_expires = rtc_tm_to_time64(&t->time);
 
@@ -818,18 +818,24 @@ static void rtc_wake_off(struct device *dev)
 }
 
 #ifdef CONFIG_X86
-/* Enable use_acpi_alarm mode for Intel platforms no earlier than 2015 */
 static void use_acpi_alarm_quirks(void)
 {
-	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_INTEL:
+		if (dmi_get_bios_year() < 2015)
+			return;
+		break;
+	case X86_VENDOR_AMD:
+	case X86_VENDOR_HYGON:
+		if (dmi_get_bios_year() < 2021)
+			return;
+		break;
+	default:
 		return;
-
+	}
 	if (!is_hpet_enabled())
 		return;
 
-	if (dmi_get_bios_year() < 2015)
-		return;
-
 	use_acpi_alarm = true;
 }
 #else
diff --git a/drivers/rtc/rtc-da9063.c b/drivers/rtc/rtc-da9063.c
index 2f5d60622564..859397541f29 100644
--- a/drivers/rtc/rtc-da9063.c
+++ b/drivers/rtc/rtc-da9063.c
@@ -377,7 +377,6 @@ static int da9063_rtc_probe(struct platform_device *pdev)
 {
 	struct da9063_compatible_rtc *rtc;
 	const struct da9063_compatible_rtc_regmap *config;
-	const struct of_device_id *match;
 	int irq_alarm;
 	u8 data[RTC_DATA_LEN];
 	int ret;
@@ -385,14 +384,11 @@ static int da9063_rtc_probe(struct platform_device *pdev)
 	if (!pdev->dev.of_node)
 		return -ENXIO;
 
-	match = of_match_node(da9063_compatible_reg_id_table,
-			      pdev->dev.of_node);
-
 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 	if (!rtc)
 		return -ENOMEM;
 
-	rtc->config = match->data;
+	rtc->config = device_get_match_data(&pdev->dev);
 	if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
 		struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
 
@@ -411,57 +407,49 @@ static int da9063_rtc_probe(struct platform_device *pdev)
 				 config->rtc_enable_reg,
 				 config->rtc_enable_mask,
 				 config->rtc_enable_mask);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to enable RTC\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret, "Failed to enable RTC\n");
 
 	ret = regmap_update_bits(rtc->regmap,
 				 config->rtc_enable_32k_crystal_reg,
 				 config->rtc_crystal_mask,
 				 config->rtc_crystal_mask);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to run 32kHz oscillator\n");
 
 	ret = regmap_update_bits(rtc->regmap,
 				 config->rtc_alarm_secs_reg,
 				 config->rtc_alarm_status_mask,
 				 0);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to access RTC alarm register\n");
 
 	ret = regmap_update_bits(rtc->regmap,
 				 config->rtc_alarm_secs_reg,
 				 DA9063_ALARM_STATUS_ALARM,
 				 DA9063_ALARM_STATUS_ALARM);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to access RTC alarm register\n");
 
 	ret = regmap_update_bits(rtc->regmap,
 				 config->rtc_alarm_year_reg,
 				 config->rtc_tick_on_mask,
 				 0);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to disable TICKs\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to disable TICKs\n");
 
 	data[RTC_SEC] = 0;
 	ret = regmap_bulk_read(rtc->regmap,
 			       config->rtc_alarm_secs_reg,
 			       &data[config->rtc_data_start],
 			       config->rtc_alarm_len);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
-			ret);
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to read initial alarm data\n");
 
 	platform_set_drvdata(pdev, rtc);
 
@@ -485,25 +473,29 @@ static int da9063_rtc_probe(struct platform_device *pdev)
 		clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc_dev->features);
 	}
 
-	irq_alarm = platform_get_irq_byname(pdev, "ALARM");
-	if (irq_alarm < 0)
+	irq_alarm = platform_get_irq_byname_optional(pdev, "ALARM");
+	if (irq_alarm >= 0) {
+		ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
+						da9063_alarm_event,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						"ALARM", rtc);
+		if (ret)
+			dev_err(&pdev->dev,
+				"Failed to request ALARM IRQ %d: %d\n",
+				irq_alarm, ret);
+
+		ret = dev_pm_set_wake_irq(&pdev->dev, irq_alarm);
+		if (ret)
+			dev_warn(&pdev->dev,
+				 "Failed to set IRQ %d as a wake IRQ: %d\n",
+				 irq_alarm, ret);
+
+		device_init_wakeup(&pdev->dev, true);
+	}  else if (irq_alarm != -ENXIO) {
 		return irq_alarm;
-
-	ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
-					da9063_alarm_event,
-					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
-					"ALARM", rtc);
-	if (ret)
-		dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
-			irq_alarm, ret);
-
-	ret = dev_pm_set_wake_irq(&pdev->dev, irq_alarm);
-	if (ret)
-		dev_warn(&pdev->dev,
-			 "Failed to set IRQ %d as a wake IRQ: %d\n",
-			 irq_alarm, ret);
-
-	device_init_wakeup(&pdev->dev, true);
+	} else {
+		clear_bit(RTC_FEATURE_ALARM, rtc->rtc_dev->features);
+	}
 
 	return devm_rtc_register_device(rtc->rtc_dev);
 }
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 89d7b085f721..1485a6ae51e6 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -536,6 +536,8 @@ static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
 	return 0;
 }
 
+#if IS_ENABLED(CONFIG_I2C)
+
 #ifdef CONFIG_PM_SLEEP
 static int ds3232_suspend(struct device *dev)
 {
@@ -564,8 +566,6 @@ static const struct dev_pm_ops ds3232_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
 };
 
-#if IS_ENABLED(CONFIG_I2C)
-
 static int ds3232_i2c_probe(struct i2c_client *client)
 {
 	struct regmap *regmap;
diff --git a/drivers/rtc/rtc-ma35d1.c b/drivers/rtc/rtc-ma35d1.c
new file mode 100644
index 000000000000..cfcfc28060f6
--- /dev/null
+++ b/drivers/rtc/rtc-ma35d1.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for Nuvoton MA35D1
+ *
+ * Copyright (C) 2023 Nuvoton Technology Corp.
+ */
+
+#include <linux/bcd.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+/* MA35D1 RTC Control Registers */
+#define MA35_REG_RTC_INIT	0x00
+#define MA35_REG_RTC_SINFASTS	0x04
+#define MA35_REG_RTC_FREQADJ	0x08
+#define MA35_REG_RTC_TIME	0x0c
+#define MA35_REG_RTC_CAL	0x10
+#define MA35_REG_RTC_CLKFMT	0x14
+#define MA35_REG_RTC_WEEKDAY	0x18
+#define MA35_REG_RTC_TALM	0x1c
+#define MA35_REG_RTC_CALM	0x20
+#define MA35_REG_RTC_LEAPYEAR	0x24
+#define MA35_REG_RTC_INTEN	0x28
+#define MA35_REG_RTC_INTSTS	0x2c
+
+/* register MA35_REG_RTC_INIT */
+#define RTC_INIT_ACTIVE		BIT(0)
+#define RTC_INIT_MAGIC_CODE	0xa5eb1357
+
+/* register MA35_REG_RTC_CLKFMT */
+#define RTC_CLKFMT_24HEN	BIT(0)
+#define RTC_CLKFMT_DCOMPEN	BIT(16)
+
+/* register MA35_REG_RTC_INTEN */
+#define RTC_INTEN_ALMIEN	BIT(0)
+#define RTC_INTEN_UIEN		BIT(1)
+#define RTC_INTEN_CLKFIEN	BIT(24)
+#define RTC_INTEN_CLKSTIEN	BIT(25)
+
+/* register MA35_REG_RTC_INTSTS */
+#define RTC_INTSTS_ALMIF	BIT(0)
+#define RTC_INTSTS_UIF		BIT(1)
+#define RTC_INTSTS_CLKFIF	BIT(24)
+#define RTC_INTSTS_CLKSTIF	BIT(25)
+
+#define RTC_INIT_TIMEOUT	250
+
+struct ma35_rtc {
+	int irq_num;
+	void __iomem *rtc_reg;
+	struct rtc_device *rtcdev;
+};
+
+static u32 rtc_reg_read(struct ma35_rtc *p, u32 offset)
+{
+	return __raw_readl(p->rtc_reg + offset);
+}
+
+static inline void rtc_reg_write(struct ma35_rtc *p, u32 offset, u32 value)
+{
+	__raw_writel(value, p->rtc_reg + offset);
+}
+
+static irqreturn_t ma35d1_rtc_interrupt(int irq, void *data)
+{
+	struct ma35_rtc *rtc = (struct ma35_rtc *)data;
+	unsigned long events = 0, rtc_irq;
+
+	rtc_irq = rtc_reg_read(rtc, MA35_REG_RTC_INTSTS);
+
+	if (rtc_irq & RTC_INTSTS_ALMIF) {
+		rtc_reg_write(rtc, MA35_REG_RTC_INTSTS, RTC_INTSTS_ALMIF);
+		events |= RTC_AF | RTC_IRQF;
+	}
+
+	rtc_update_irq(rtc->rtcdev, 1, events);
+
+	return IRQ_HANDLED;
+}
+
+static int ma35d1_rtc_init(struct ma35_rtc *rtc, u32 ms_timeout)
+{
+	const unsigned long timeout = jiffies + msecs_to_jiffies(ms_timeout);
+
+	do {
+		if (rtc_reg_read(rtc, MA35_REG_RTC_INIT) & RTC_INIT_ACTIVE)
+			return 0;
+
+		rtc_reg_write(rtc, MA35_REG_RTC_INIT, RTC_INIT_MAGIC_CODE);
+
+		mdelay(1);
+
+	} while (time_before(jiffies, timeout));
+
+	return -ETIMEDOUT;
+}
+
+static int ma35d1_alarm_irq_enable(struct device *dev, u32 enabled)
+{
+	struct ma35_rtc *rtc = dev_get_drvdata(dev);
+	u32 reg_ien;
+
+	reg_ien = rtc_reg_read(rtc, MA35_REG_RTC_INTEN);
+
+	if (enabled)
+		rtc_reg_write(rtc, MA35_REG_RTC_INTEN, reg_ien | RTC_INTEN_ALMIEN);
+	else
+		rtc_reg_write(rtc, MA35_REG_RTC_INTEN, reg_ien & ~RTC_INTEN_ALMIEN);
+
+	return 0;
+}
+
+static int ma35d1_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct ma35_rtc *rtc = dev_get_drvdata(dev);
+	u32 time, cal, wday;
+
+	do {
+		time = rtc_reg_read(rtc, MA35_REG_RTC_TIME);
+		cal  = rtc_reg_read(rtc, MA35_REG_RTC_CAL);
+		wday = rtc_reg_read(rtc, MA35_REG_RTC_WEEKDAY);
+	} while (time != rtc_reg_read(rtc, MA35_REG_RTC_TIME) ||
+		 cal != rtc_reg_read(rtc, MA35_REG_RTC_CAL));
+
+	tm->tm_mday = bcd2bin(cal >> 0);
+	tm->tm_wday = wday;
+	tm->tm_mon = bcd2bin(cal >> 8);
+	tm->tm_mon = tm->tm_mon - 1;
+	tm->tm_year = bcd2bin(cal >> 16) + 100;
+
+	tm->tm_sec = bcd2bin(time >> 0);
+	tm->tm_min = bcd2bin(time >> 8);
+	tm->tm_hour = bcd2bin(time >> 16);
+
+	return rtc_valid_tm(tm);
+}
+
+static int ma35d1_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct ma35_rtc *rtc = dev_get_drvdata(dev);
+	u32 val;
+
+	val = bin2bcd(tm->tm_mday) << 0 | bin2bcd(tm->tm_mon + 1) << 8 |
+	      bin2bcd(tm->tm_year - 100) << 16;
+	rtc_reg_write(rtc, MA35_REG_RTC_CAL, val);
+
+	val = bin2bcd(tm->tm_sec) << 0 | bin2bcd(tm->tm_min) << 8 |
+	      bin2bcd(tm->tm_hour) << 16;
+	rtc_reg_write(rtc, MA35_REG_RTC_TIME, val);
+
+	val = tm->tm_wday;
+	rtc_reg_write(rtc, MA35_REG_RTC_WEEKDAY, val);
+
+	return 0;
+}
+
+static int ma35d1_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct ma35_rtc *rtc = dev_get_drvdata(dev);
+	u32 talm, calm;
+
+	talm = rtc_reg_read(rtc, MA35_REG_RTC_TALM);
+	calm = rtc_reg_read(rtc, MA35_REG_RTC_CALM);
+
+	alrm->time.tm_mday = bcd2bin(calm >> 0);
+	alrm->time.tm_mon = bcd2bin(calm >> 8);
+	alrm->time.tm_mon = alrm->time.tm_mon - 1;
+
+	alrm->time.tm_year = bcd2bin(calm >> 16) + 100;
+
+	alrm->time.tm_sec = bcd2bin(talm >> 0);
+	alrm->time.tm_min = bcd2bin(talm >> 8);
+	alrm->time.tm_hour = bcd2bin(talm >> 16);
+
+	return rtc_valid_tm(&alrm->time);
+}
+
+static int ma35d1_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct ma35_rtc *rtc = dev_get_drvdata(dev);
+	unsigned long val;
+
+	val = bin2bcd(alrm->time.tm_mday) << 0 | bin2bcd(alrm->time.tm_mon + 1) << 8 |
+	      bin2bcd(alrm->time.tm_year - 100) << 16;
+	rtc_reg_write(rtc, MA35_REG_RTC_CALM, val);
+
+	val = bin2bcd(alrm->time.tm_sec) << 0 | bin2bcd(alrm->time.tm_min) << 8 |
+	      bin2bcd(alrm->time.tm_hour) << 16;
+	rtc_reg_write(rtc, MA35_REG_RTC_TALM, val);
+
+	ma35d1_alarm_irq_enable(dev, alrm->enabled);
+
+	return 0;
+}
+
+static const struct rtc_class_ops ma35d1_rtc_ops = {
+	.read_time = ma35d1_rtc_read_time,
+	.set_time = ma35d1_rtc_set_time,
+	.read_alarm = ma35d1_rtc_read_alarm,
+	.set_alarm = ma35d1_rtc_set_alarm,
+	.alarm_irq_enable = ma35d1_alarm_irq_enable,
+};
+
+static int ma35d1_rtc_probe(struct platform_device *pdev)
+{
+	struct ma35_rtc *rtc;
+	struct clk *clk;
+	int ret;
+
+	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+	if (!rtc)
+		return -ENOMEM;
+
+	rtc->rtc_reg = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rtc->rtc_reg))
+		return PTR_ERR(rtc->rtc_reg);
+
+	clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(clk), "failed to find rtc clock\n");
+
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
+	if (!(rtc_reg_read(rtc, MA35_REG_RTC_INIT) & RTC_INIT_ACTIVE)) {
+		ret = ma35d1_rtc_init(rtc, RTC_INIT_TIMEOUT);
+		if (ret)
+			return dev_err_probe(&pdev->dev, ret, "rtc init failed\n");
+	}
+
+	rtc->irq_num = platform_get_irq(pdev, 0);
+
+	ret = devm_request_irq(&pdev->dev, rtc->irq_num, ma35d1_rtc_interrupt,
+			       IRQF_NO_SUSPEND, "ma35d1rtc", rtc);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "Failed to request rtc irq\n");
+
+	platform_set_drvdata(pdev, rtc);
+
+	device_init_wakeup(&pdev->dev, true);
+
+	rtc->rtcdev = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(rtc->rtcdev))
+		return PTR_ERR(rtc->rtcdev);
+
+	rtc->rtcdev->ops = &ma35d1_rtc_ops;
+	rtc->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	rtc->rtcdev->range_max = RTC_TIMESTAMP_END_2099;
+
+	ret = devm_rtc_register_device(rtc->rtcdev);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "Failed to register rtc device\n");
+
+	return 0;
+}
+
+static int ma35d1_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct ma35_rtc *rtc = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev))
+		enable_irq_wake(rtc->irq_num);
+
+	return 0;
+}
+
+static int ma35d1_rtc_resume(struct platform_device *pdev)
+{
+	struct ma35_rtc *rtc = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev))
+		disable_irq_wake(rtc->irq_num);
+
+	return 0;
+}
+
+static const struct of_device_id ma35d1_rtc_of_match[] = {
+	{ .compatible = "nuvoton,ma35d1-rtc", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ma35d1_rtc_of_match);
+
+static struct platform_driver ma35d1_rtc_driver = {
+	.suspend    = ma35d1_rtc_suspend,
+	.resume     = ma35d1_rtc_resume,
+	.probe      = ma35d1_rtc_probe,
+	.driver		= {
+		.name	= "rtc-ma35d1",
+		.of_match_table = ma35d1_rtc_of_match,
+	},
+};
+
+module_platform_driver(ma35d1_rtc_driver);
+
+MODULE_AUTHOR("Ming-Jen Chen <mjchen@nuvoton.com>");
+MODULE_DESCRIPTION("MA35D1 RTC driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/rtc/rtc-max31335.c b/drivers/rtc/rtc-max31335.c
new file mode 100644
index 000000000000..402fda8fd548
--- /dev/null
+++ b/drivers/rtc/rtc-max31335.c
@@ -0,0 +1,697 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for the MAX31335
+ *
+ * Copyright (C) 2023 Analog Devices
+ *
+ * Antoniu Miclaus <antoniu.miclaus@analog.com>
+ *
+ */
+
+#include <asm-generic/unaligned.h>
+#include <linux/bcd.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/util_macros.h>
+
+/* MAX31335 Register Map */
+#define MAX31335_STATUS1			0x00
+#define MAX31335_INT_EN1			0x01
+#define MAX31335_STATUS2			0x02
+#define MAX31335_INT_EN2			0x03
+#define MAX31335_RTC_RESET			0x04
+#define MAX31335_RTC_CONFIG			0x05
+#define MAX31335_RTC_CONFIG2			0x06
+#define MAX31335_TIMESTAMP_CONFIG		0x07
+#define MAX31335_TIMER_CONFIG			0x08
+#define MAX31335_SECONDS_1_128			0x09
+#define MAX31335_SECONDS			0x0A
+#define MAX31335_MINUTES			0x0B
+#define MAX31335_HOURS				0x0C
+#define MAX31335_DAY				0x0D
+#define MAX31335_DATE				0x0E
+#define MAX31335_MONTH				0x0F
+#define MAX31335_YEAR				0x0F
+#define MAX31335_ALM1_SEC			0x11
+#define MAX31335_ALM1_MIN			0x12
+#define MAX31335_ALM1_HRS			0x13
+#define MAX31335_ALM1_DAY_DATE			0x14
+#define MAX31335_ALM1_MON			0x15
+#define MAX31335_ALM1_YEAR			0x16
+#define MAX31335_ALM2_MIN			0x17
+#define MAX31335_ALM2_HRS			0x18
+#define MAX31335_ALM2_DAY_DATE			0x19
+#define MAX31335_TIMER_COUNT			0x1A
+#define MAX31335_TIMER_INIT			0x1B
+#define MAX31335_PWR_MGMT			0x1C
+#define MAX31335_TRICKLE_REG			0x1D
+#define MAX31335_AGING_OFFSET			0x1E
+#define MAX31335_TS_CONFIG			0x30
+#define MAX31335_TEMP_ALARM_HIGH_MSB		0x31
+#define MAX31335_TEMP_ALARM_HIGH_LSB		0x32
+#define MAX31335_TEMP_ALARM_LOW_MSB		0x33
+#define MAX31335_TEMP_ALARM_LOW_LSB		0x34
+#define MAX31335_TEMP_DATA_MSB			0x35
+#define MAX31335_TEMP_DATA_LSB			0x36
+#define MAX31335_TS0_SEC_1_128			0x40
+#define MAX31335_TS0_SEC			0x41
+#define MAX31335_TS0_MIN			0x42
+#define MAX31335_TS0_HOUR			0x43
+#define MAX31335_TS0_DATE			0x44
+#define MAX31335_TS0_MONTH			0x45
+#define MAX31335_TS0_YEAR			0x46
+#define MAX31335_TS0_FLAGS			0x47
+#define MAX31335_TS1_SEC_1_128			0x48
+#define MAX31335_TS1_SEC			0x49
+#define MAX31335_TS1_MIN			0x4A
+#define MAX31335_TS1_HOUR			0x4B
+#define MAX31335_TS1_DATE			0x4C
+#define MAX31335_TS1_MONTH			0x4D
+#define MAX31335_TS1_YEAR			0x4E
+#define MAX31335_TS1_FLAGS			0x4F
+#define MAX31335_TS2_SEC_1_128			0x50
+#define MAX31335_TS2_SEC			0x51
+#define MAX31335_TS2_MIN			0x52
+#define MAX31335_TS2_HOUR			0x53
+#define MAX31335_TS2_DATE			0x54
+#define MAX31335_TS2_MONTH			0x55
+#define MAX31335_TS2_YEAR			0x56
+#define MAX31335_TS2_FLAGS			0x57
+#define MAX31335_TS3_SEC_1_128			0x58
+#define MAX31335_TS3_SEC			0x59
+#define MAX31335_TS3_MIN			0x5A
+#define MAX31335_TS3_HOUR			0x5B
+#define MAX31335_TS3_DATE			0x5C
+#define MAX31335_TS3_MONTH			0x5D
+#define MAX31335_TS3_YEAR			0x5E
+#define MAX31335_TS3_FLAGS			0x5F
+
+/* MAX31335_STATUS1 Bit Definitions */
+#define MAX31335_STATUS1_PSDECT			BIT(7)
+#define MAX31335_STATUS1_OSF			BIT(6)
+#define MAX31335_STATUS1_PFAIL			BIT(5)
+#define MAX31335_STATUS1_VBATLOW		BIT(4)
+#define MAX31335_STATUS1_DIF			BIT(3)
+#define MAX31335_STATUS1_TIF			BIT(2)
+#define MAX31335_STATUS1_A2F			BIT(1)
+#define MAX31335_STATUS1_A1F			BIT(0)
+
+/* MAX31335_INT_EN1 Bit Definitions */
+#define MAX31335_INT_EN1_DOSF			BIT(6)
+#define MAX31335_INT_EN1_PFAILE			BIT(5)
+#define MAX31335_INT_EN1_VBATLOWE		BIT(4)
+#define MAX31335_INT_EN1_DIE			BIT(3)
+#define MAX31335_INT_EN1_TIE			BIT(2)
+#define MAX31335_INT_EN1_A2IE			BIT(1)
+#define MAX31335_INT_EN1_A1IE			BIT(0)
+
+/* MAX31335_STATUS2 Bit Definitions */
+#define MAX31335_STATUS2_TEMP_RDY		BIT(2)
+#define MAX31335_STATUS2_OTF			BIT(1)
+#define MAX31335_STATUS2_UTF			BIT(0)
+
+/* MAX31335_INT_EN2 Bit Definitions */
+#define MAX31335_INT_EN2_TEMP_RDY_EN		BIT(2)
+#define MAX31335_INT_EN2_OTIE			BIT(1)
+#define MAX31335_INT_EN2_UTIE			BIT(0)
+
+/* MAX31335_RTC_RESET Bit Definitions */
+#define MAX31335_RTC_RESET_SWRST		BIT(0)
+
+/* MAX31335_RTC_CONFIG1 Bit Definitions */
+#define MAX31335_RTC_CONFIG1_EN_IO		BIT(6)
+#define MAX31335_RTC_CONFIG1_A1AC		GENMASK(5, 4)
+#define MAX31335_RTC_CONFIG1_DIP		BIT(3)
+#define MAX31335_RTC_CONFIG1_I2C_TIMEOUT	BIT(1)
+#define MAX31335_RTC_CONFIG1_EN_OSC		BIT(0)
+
+/* MAX31335_RTC_CONFIG2 Bit Definitions */
+#define MAX31335_RTC_CONFIG2_ENCLKO		BIT(2)
+#define MAX31335_RTC_CONFIG2_CLKO_HZ		GENMASK(1, 0)
+
+/* MAX31335_TIMESTAMP_CONFIG Bit Definitions */
+#define MAX31335_TIMESTAMP_CONFIG_TSVLOW	BIT(5)
+#define MAX31335_TIMESTAMP_CONFIG_TSPWM		BIT(4)
+#define MAX31335_TIMESTAMP_CONFIG_TSDIN		BIT(3)
+#define MAX31335_TIMESTAMP_CONFIG_TSOW		BIT(2)
+#define MAX31335_TIMESTAMP_CONFIG_TSR		BIT(1)
+#define MAX31335_TIMESTAMP_CONFIG_TSE		BIT(0)
+
+/* MAX31335_TIMER_CONFIG Bit Definitions */
+#define MAX31335_TIMER_CONFIG_TE		BIT(4)
+#define MAX31335_TIMER_CONFIG_TPAUSE		BIT(3)
+#define MAX31335_TIMER_CONFIG_TRPT		BIT(2)
+#define MAX31335_TIMER_CONFIG_TFS		GENMASK(1, 0)
+
+/* MAX31335_HOURS Bit Definitions */
+#define MAX31335_HOURS_F_24_12			BIT(6)
+#define MAX31335_HOURS_HR_20_AM_PM		BIT(5)
+
+/* MAX31335_MONTH Bit Definitions */
+#define MAX31335_MONTH_CENTURY			BIT(7)
+
+/* MAX31335_PWR_MGMT Bit Definitions */
+#define MAX31335_PWR_MGMT_PFVT			BIT(0)
+
+/* MAX31335_TRICKLE_REG Bit Definitions */
+#define MAX31335_TRICKLE_REG_TRICKLE		GENMASK(3, 1)
+#define MAX31335_TRICKLE_REG_EN_TRICKLE		BIT(0)
+
+/* MAX31335_TS_CONFIG Bit Definitions */
+#define MAX31335_TS_CONFIG_AUTO			BIT(4)
+#define MAX31335_TS_CONFIG_CONVERT_T		BIT(3)
+#define MAX31335_TS_CONFIG_TSINT		GENMASK(2, 0)
+
+/* MAX31335_TS_FLAGS Bit Definitions */
+#define MAX31335_TS_FLAGS_VLOWF			BIT(3)
+#define MAX31335_TS_FLAGS_VBATF			BIT(2)
+#define MAX31335_TS_FLAGS_VCCF			BIT(1)
+#define MAX31335_TS_FLAGS_DINF			BIT(0)
+
+/* MAX31335 Miscellaneous Definitions */
+#define MAX31335_TRICKLE_SCHOTTKY_DIODE		1
+#define MAX31335_TRICKLE_STANDARD_DIODE		4
+#define MAX31335_RAM_SIZE			32
+#define MAX31335_TIME_SIZE			0x07
+
+#define clk_hw_to_max31335(_hw) container_of(_hw, struct max31335_data, clkout)
+
+struct max31335_data {
+	struct regmap *regmap;
+	struct rtc_device *rtc;
+	struct clk_hw clkout;
+};
+
+static const int max31335_clkout_freq[] = { 1, 64, 1024, 32768 };
+
+static const u16 max31335_trickle_resistors[] = {3000, 6000, 11000};
+
+static bool max31335_volatile_reg(struct device *dev, unsigned int reg)
+{
+	/* time keeping registers */
+	if (reg >= MAX31335_SECONDS &&
+	    reg < MAX31335_SECONDS + MAX31335_TIME_SIZE)
+		return true;
+
+	/* interrupt status register */
+	if (reg == MAX31335_INT_EN1_A1IE)
+		return true;
+
+	/* temperature registers */
+	if (reg == MAX31335_TEMP_DATA_MSB || reg == MAX31335_TEMP_DATA_LSB)
+		return true;
+
+	return false;
+}
+
+static const struct regmap_config regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x5F,
+	.volatile_reg = max31335_volatile_reg,
+};
+
+static int max31335_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 date[7];
+	int ret;
+
+	ret = regmap_bulk_read(max31335->regmap, MAX31335_SECONDS, date,
+			       sizeof(date));
+	if (ret)
+		return ret;
+
+	tm->tm_sec  = bcd2bin(date[0] & 0x7f);
+	tm->tm_min  = bcd2bin(date[1] & 0x7f);
+	tm->tm_hour = bcd2bin(date[2] & 0x3f);
+	tm->tm_wday = bcd2bin(date[3] & 0x7) - 1;
+	tm->tm_mday = bcd2bin(date[4] & 0x3f);
+	tm->tm_mon  = bcd2bin(date[5] & 0x1f) - 1;
+	tm->tm_year = bcd2bin(date[6]) + 100;
+
+	if (FIELD_GET(MAX31335_MONTH_CENTURY, date[5]))
+		tm->tm_year += 100;
+
+	return 0;
+}
+
+static int max31335_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 date[7];
+
+	date[0] = bin2bcd(tm->tm_sec);
+	date[1] = bin2bcd(tm->tm_min);
+	date[2] = bin2bcd(tm->tm_hour);
+	date[3] = bin2bcd(tm->tm_wday + 1);
+	date[4] = bin2bcd(tm->tm_mday);
+	date[5] = bin2bcd(tm->tm_mon + 1);
+	date[6] = bin2bcd(tm->tm_year % 100);
+
+	if (tm->tm_year >= 200)
+		date[5] |= FIELD_PREP(MAX31335_MONTH_CENTURY, 1);
+
+	return regmap_bulk_write(max31335->regmap, MAX31335_SECONDS, date,
+				 sizeof(date));
+}
+
+static int max31335_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	int ret, ctrl, status;
+	struct rtc_time time;
+	u8 regs[6];
+
+	ret = regmap_bulk_read(max31335->regmap, MAX31335_ALM1_SEC, regs,
+			       sizeof(regs));
+	if (ret)
+		return ret;
+
+	alrm->time.tm_sec  = bcd2bin(regs[0] & 0x7f);
+	alrm->time.tm_min  = bcd2bin(regs[1] & 0x7f);
+	alrm->time.tm_hour = bcd2bin(regs[2] & 0x3f);
+	alrm->time.tm_mday = bcd2bin(regs[3] & 0x3f);
+	alrm->time.tm_mon  = bcd2bin(regs[4] & 0x1f) - 1;
+	alrm->time.tm_year = bcd2bin(regs[5]) + 100;
+
+	ret = max31335_read_time(dev, &time);
+	if (ret)
+		return ret;
+
+	if (time.tm_year >= 200)
+		alrm->time.tm_year += 100;
+
+	ret = regmap_read(max31335->regmap, MAX31335_INT_EN1, &ctrl);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(max31335->regmap, MAX31335_STATUS1, &status);
+	if (ret)
+		return ret;
+
+	alrm->enabled = FIELD_GET(MAX31335_INT_EN1_A1IE, ctrl);
+	alrm->pending = FIELD_GET(MAX31335_STATUS1_A1F, status);
+
+	return 0;
+}
+
+static int max31335_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	unsigned int reg;
+	u8 regs[6];
+	int ret;
+
+	regs[0] = bin2bcd(alrm->time.tm_sec);
+	regs[1] = bin2bcd(alrm->time.tm_min);
+	regs[2] = bin2bcd(alrm->time.tm_hour);
+	regs[3] = bin2bcd(alrm->time.tm_mday);
+	regs[4] = bin2bcd(alrm->time.tm_mon + 1);
+	regs[5] = bin2bcd(alrm->time.tm_year % 100);
+
+	ret = regmap_bulk_write(max31335->regmap, MAX31335_ALM1_SEC,
+				regs, sizeof(regs));
+	if (ret)
+		return ret;
+
+	reg = FIELD_PREP(MAX31335_INT_EN1_A1IE, alrm->enabled);
+	ret = regmap_update_bits(max31335->regmap, MAX31335_INT_EN1,
+				 MAX31335_INT_EN1_A1IE, reg);
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(max31335->regmap, MAX31335_STATUS1,
+				 MAX31335_STATUS1_A1F, 0);
+
+	return 0;
+}
+
+static int max31335_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+
+	return regmap_update_bits(max31335->regmap, MAX31335_INT_EN1,
+				  MAX31335_INT_EN1_A1IE, enabled);
+}
+
+static irqreturn_t max31335_handle_irq(int irq, void *dev_id)
+{
+	struct max31335_data *max31335 = dev_id;
+	bool status;
+	int ret;
+
+	ret = regmap_update_bits_check(max31335->regmap, MAX31335_STATUS1,
+				       MAX31335_STATUS1_A1F, 0, &status);
+	if (ret)
+		return IRQ_HANDLED;
+
+	if (status)
+		rtc_update_irq(max31335->rtc, 1, RTC_AF | RTC_IRQF);
+
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops max31335_rtc_ops = {
+	.read_time = max31335_read_time,
+	.set_time = max31335_set_time,
+	.read_alarm = max31335_read_alarm,
+	.set_alarm = max31335_set_alarm,
+	.alarm_irq_enable = max31335_alarm_irq_enable,
+};
+
+static int max31335_trickle_charger_setup(struct device *dev,
+					  struct max31335_data *max31335)
+{
+	u32 ohms, chargeable;
+	int i, trickle_cfg;
+	const char *diode;
+
+	if (device_property_read_u32(dev, "aux-voltage-chargeable",
+				     &chargeable))
+		return 0;
+
+	if (device_property_read_u32(dev, "trickle-resistor-ohms", &ohms))
+		return 0;
+
+	if (device_property_read_string(dev, "adi,tc-diode", &diode))
+		return 0;
+
+	if (!strcmp(diode, "schottky"))
+		trickle_cfg = MAX31335_TRICKLE_SCHOTTKY_DIODE;
+	else if (!strcmp(diode, "standard+schottky"))
+		trickle_cfg = MAX31335_TRICKLE_STANDARD_DIODE;
+	else
+		return dev_err_probe(dev, -EINVAL,
+				     "Invalid tc-diode value: %s\n", diode);
+
+	for (i = 0; i < ARRAY_SIZE(max31335_trickle_resistors); i++)
+		if (ohms == max31335_trickle_resistors[i])
+			break;
+
+	if (i >= ARRAY_SIZE(max31335_trickle_resistors))
+		return 0;
+
+	i = i + trickle_cfg;
+
+	return regmap_write(max31335->regmap, MAX31335_TRICKLE_REG,
+			    FIELD_PREP(MAX31335_TRICKLE_REG_TRICKLE, i) |
+			    FIELD_PREP(MAX31335_TRICKLE_REG_EN_TRICKLE,
+				       chargeable));
+}
+
+static unsigned long max31335_clkout_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int freq_mask;
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(max31335->regmap, MAX31335_RTC_CONFIG2, &reg);
+	if (ret)
+		return 0;
+
+	freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1;
+
+	return max31335_clkout_freq[reg & freq_mask];
+}
+
+static long max31335_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+				       unsigned long *prate)
+{
+	int index;
+
+	index = find_closest(rate, max31335_clkout_freq,
+			     ARRAY_SIZE(max31335_clkout_freq));
+
+	return max31335_clkout_freq[index];
+}
+
+static int max31335_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int freq_mask;
+	int index;
+
+	index = find_closest(rate, max31335_clkout_freq,
+			     ARRAY_SIZE(max31335_clkout_freq));
+	freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1;
+
+	return regmap_update_bits(max31335->regmap, MAX31335_RTC_CONFIG2,
+				  freq_mask, index);
+}
+
+static int max31335_clkout_enable(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+
+	return regmap_set_bits(max31335->regmap, MAX31335_RTC_CONFIG2,
+			       MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static void max31335_clkout_disable(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+
+	regmap_clear_bits(max31335->regmap, MAX31335_RTC_CONFIG2,
+			  MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static int max31335_clkout_is_enabled(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(max31335->regmap, MAX31335_RTC_CONFIG2, &reg);
+	if (ret)
+		return ret;
+
+	return !!(reg & MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static const struct clk_ops max31335_clkout_ops = {
+	.recalc_rate = max31335_clkout_recalc_rate,
+	.round_rate = max31335_clkout_round_rate,
+	.set_rate = max31335_clkout_set_rate,
+	.enable = max31335_clkout_enable,
+	.disable = max31335_clkout_disable,
+	.is_enabled = max31335_clkout_is_enabled,
+};
+
+static struct clk_init_data max31335_clk_init = {
+	.name = "max31335-clkout",
+	.ops = &max31335_clkout_ops,
+};
+
+static int max31335_nvmem_reg_read(void *priv, unsigned int offset,
+				   void *val, size_t bytes)
+{
+	struct max31335_data *max31335 = priv;
+	unsigned int reg = MAX31335_TS0_SEC_1_128 + offset;
+
+	return regmap_bulk_read(max31335->regmap, reg, val, bytes);
+}
+
+static int max31335_nvmem_reg_write(void *priv, unsigned int offset,
+				    void *val, size_t bytes)
+{
+	struct max31335_data *max31335 = priv;
+	unsigned int reg = MAX31335_TS0_SEC_1_128 + offset;
+
+	return regmap_bulk_write(max31335->regmap, reg, val, bytes);
+}
+
+static struct nvmem_config max31335_nvmem_cfg = {
+	.reg_read = max31335_nvmem_reg_read,
+	.reg_write = max31335_nvmem_reg_write,
+	.word_size = 8,
+	.size = MAX31335_RAM_SIZE,
+};
+
+#if IS_REACHABLE(HWMON)
+static int max31335_read_temp(struct device *dev, enum hwmon_sensor_types type,
+			      u32 attr, int channel, long *val)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 reg[2];
+	s16 temp;
+	int ret;
+
+	if (type != hwmon_temp || attr != hwmon_temp_input)
+		return -EOPNOTSUPP;
+
+	ret = regmap_bulk_read(max31335->regmap, MAX31335_TEMP_DATA_MSB,
+			       reg, 2);
+	if (ret)
+		return ret;
+
+	temp = get_unaligned_be16(reg);
+
+	*val = (temp / 64) * 250;
+
+	return 0;
+}
+
+static umode_t max31335_is_visible(const void *data,
+				   enum hwmon_sensor_types type,
+				   u32 attr, int channel)
+{
+	if (type == hwmon_temp && attr == hwmon_temp_input)
+		return 0444;
+
+	return 0;
+}
+
+static const struct hwmon_channel_info *max31335_info[] = {
+	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
+	NULL
+};
+
+static const struct hwmon_ops max31335_hwmon_ops = {
+	.is_visible = max31335_is_visible,
+	.read = max31335_read_temp,
+};
+
+static const struct hwmon_chip_info max31335_chip_info = {
+	.ops = &max31335_hwmon_ops,
+	.info = max31335_info,
+};
+#endif
+
+static int max31335_clkout_register(struct device *dev)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	int ret;
+
+	if (!device_property_present(dev, "#clock-cells"))
+		return regmap_clear_bits(max31335->regmap, MAX31335_RTC_CONFIG2,
+					 MAX31335_RTC_CONFIG2_ENCLKO);
+
+	max31335->clkout.init = &max31335_clk_init;
+
+	ret = devm_clk_hw_register(dev, &max31335->clkout);
+	if (ret)
+		return dev_err_probe(dev, ret, "cannot register clock\n");
+
+	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+					  &max31335->clkout);
+	if (ret)
+		return dev_err_probe(dev, ret, "cannot add hw provider\n");
+
+	max31335->clkout.clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(max31335->clkout.clk))
+		return dev_err_probe(dev, PTR_ERR(max31335->clkout.clk),
+				     "cannot enable clkout\n");
+
+	return 0;
+}
+
+static int max31335_probe(struct i2c_client *client)
+{
+	struct max31335_data *max31335;
+#if IS_REACHABLE(HWMON)
+	struct device *hwmon;
+#endif
+	int ret;
+
+	max31335 = devm_kzalloc(&client->dev, sizeof(*max31335), GFP_KERNEL);
+	if (!max31335)
+		return -ENOMEM;
+
+	max31335->regmap = devm_regmap_init_i2c(client, &regmap_config);
+	if (IS_ERR(max31335->regmap))
+		return PTR_ERR(max31335->regmap);
+
+	i2c_set_clientdata(client, max31335);
+
+	max31335->rtc = devm_rtc_allocate_device(&client->dev);
+	if (IS_ERR(max31335->rtc))
+		return PTR_ERR(max31335->rtc);
+
+	max31335->rtc->ops = &max31335_rtc_ops;
+	max31335->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	max31335->rtc->range_max = RTC_TIMESTAMP_END_2199;
+	max31335->rtc->alarm_offset_max = 24 * 60 * 60;
+
+	ret = max31335_clkout_register(&client->dev);
+	if (ret)
+		return ret;
+
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, max31335_handle_irq,
+						IRQF_ONESHOT,
+						"max31335", max31335);
+		if (ret) {
+			dev_warn(&client->dev,
+				 "unable to request IRQ, alarm max31335 disabled\n");
+			client->irq = 0;
+		}
+	}
+
+	if (!client->irq)
+		clear_bit(RTC_FEATURE_ALARM, max31335->rtc->features);
+
+	max31335_nvmem_cfg.priv = max31335;
+	ret = devm_rtc_nvmem_register(max31335->rtc, &max31335_nvmem_cfg);
+	if (ret)
+		return dev_err_probe(&client->dev, ret,
+				     "cannot register rtc nvmem\n");
+
+#if IS_REACHABLE(HWMON)
+	hwmon = devm_hwmon_device_register_with_info(&client->dev, client->name,
+						     max31335,
+						     &max31335_chip_info,
+						     NULL);
+	if (IS_ERR(hwmon))
+		return dev_err_probe(&client->dev, PTR_ERR(hwmon),
+				     "cannot register hwmon device\n");
+#endif
+
+	ret = max31335_trickle_charger_setup(&client->dev, max31335);
+	if (ret)
+		return ret;
+
+	return devm_rtc_register_device(max31335->rtc);
+}
+
+static const struct i2c_device_id max31335_id[] = {
+	{ "max31335", 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, max31335_id);
+
+static const struct of_device_id max31335_of_match[] = {
+	{ .compatible = "adi,max31335" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, max31335_of_match);
+
+static struct i2c_driver max31335_driver = {
+	.driver = {
+		.name = "rtc-max31335",
+		.of_match_table = max31335_of_match,
+	},
+	.probe = max31335_probe,
+	.id_table = max31335_id,
+};
+module_i2c_driver(max31335_driver);
+
+MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com>");
+MODULE_DESCRIPTION("MAX31335 RTC driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c
index f1c09f1db044..651bf3c279c7 100644
--- a/drivers/rtc/rtc-mc146818-lib.c
+++ b/drivers/rtc/rtc-mc146818-lib.c
@@ -8,26 +8,31 @@
 #include <linux/acpi.h>
 #endif
 
+#define UIP_RECHECK_DELAY		100	/* usec */
+#define UIP_RECHECK_DELAY_MS		(USEC_PER_MSEC / UIP_RECHECK_DELAY)
+#define UIP_RECHECK_LOOPS_MS(x)		(x / UIP_RECHECK_DELAY_MS)
+
 /*
  * Execute a function while the UIP (Update-in-progress) bit of the RTC is
- * unset.
+ * unset. The timeout is configurable by the caller in ms.
  *
  * Warning: callback may be executed more then once.
  */
 bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
+			int timeout,
 			void *param)
 {
 	int i;
 	unsigned long flags;
 	unsigned char seconds;
 
-	for (i = 0; i < 100; i++) {
+	for (i = 0; UIP_RECHECK_LOOPS_MS(i) < timeout; i++) {
 		spin_lock_irqsave(&rtc_lock, flags);
 
 		/*
 		 * Check whether there is an update in progress during which the
 		 * readout is unspecified. The maximum update time is ~2ms. Poll
-		 * every 100 usec for completion.
+		 * for completion.
 		 *
 		 * Store the second value before checking UIP so a long lasting
 		 * NMI which happens to hit after the UIP check cannot make
@@ -37,7 +42,7 @@ bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
 
 		if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) {
 			spin_unlock_irqrestore(&rtc_lock, flags);
-			udelay(100);
+			udelay(UIP_RECHECK_DELAY);
 			continue;
 		}
 
@@ -56,7 +61,7 @@ bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
 		 */
 		if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) {
 			spin_unlock_irqrestore(&rtc_lock, flags);
-			udelay(100);
+			udelay(UIP_RECHECK_DELAY);
 			continue;
 		}
 
@@ -72,6 +77,10 @@ bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
 		}
 		spin_unlock_irqrestore(&rtc_lock, flags);
 
+		if (UIP_RECHECK_LOOPS_MS(i) >= 100)
+			pr_warn("Reading current time from RTC took around %li ms\n",
+				UIP_RECHECK_LOOPS_MS(i));
+
 		return true;
 	}
 	return false;
@@ -84,7 +93,7 @@ EXPORT_SYMBOL_GPL(mc146818_avoid_UIP);
  */
 bool mc146818_does_rtc_work(void)
 {
-	return mc146818_avoid_UIP(NULL, NULL);
+	return mc146818_avoid_UIP(NULL, 1000, NULL);
 }
 EXPORT_SYMBOL_GPL(mc146818_does_rtc_work);
 
@@ -130,15 +139,27 @@ static void mc146818_get_time_callback(unsigned char seconds, void *param_in)
 	p->ctrl = CMOS_READ(RTC_CONTROL);
 }
 
-int mc146818_get_time(struct rtc_time *time)
+/**
+ * mc146818_get_time - Get the current time from the RTC
+ * @time: pointer to struct rtc_time to store the current time
+ * @timeout: timeout value in ms
+ *
+ * This function reads the current time from the RTC and stores it in the
+ * provided struct rtc_time. The timeout parameter specifies the maximum
+ * time to wait for the RTC to become ready.
+ *
+ * Return: 0 on success, -ETIMEDOUT if the RTC did not become ready within
+ * the specified timeout, or another error code if an error occurred.
+ */
+int mc146818_get_time(struct rtc_time *time, int timeout)
 {
 	struct mc146818_get_time_callback_param p = {
 		.time = time
 	};
 
-	if (!mc146818_avoid_UIP(mc146818_get_time_callback, &p)) {
+	if (!mc146818_avoid_UIP(mc146818_get_time_callback, timeout, &p)) {
 		memset(time, 0, sizeof(*time));
-		return -EIO;
+		return -ETIMEDOUT;
 	}
 
 	if (!(p.ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
diff --git a/drivers/rtc/rtc-nct3018y.c b/drivers/rtc/rtc-nct3018y.c
index ed4e606be8e5..f488a189a465 100644
--- a/drivers/rtc/rtc-nct3018y.c
+++ b/drivers/rtc/rtc-nct3018y.c
@@ -23,6 +23,7 @@
 #define NCT3018Y_REG_CTRL	0x0A /* timer control */
 #define NCT3018Y_REG_ST		0x0B /* status */
 #define NCT3018Y_REG_CLKO	0x0C /* clock out */
+#define NCT3018Y_REG_PART	0x21 /* part info */
 
 #define NCT3018Y_BIT_AF		BIT(7)
 #define NCT3018Y_BIT_ST		BIT(7)
@@ -37,10 +38,12 @@
 #define NCT3018Y_REG_BAT_MASK		0x07
 #define NCT3018Y_REG_CLKO_F_MASK	0x03 /* frequenc mask */
 #define NCT3018Y_REG_CLKO_CKE		0x80 /* clock out enabled */
+#define NCT3018Y_REG_PART_NCT3018Y	0x02
 
 struct nct3018y {
 	struct rtc_device *rtc;
 	struct i2c_client *client;
+	int part_num;
 #ifdef CONFIG_COMMON_CLK
 	struct clk_hw clkout_hw;
 #endif
@@ -177,8 +180,27 @@ static int nct3018y_rtc_read_time(struct device *dev, struct rtc_time *tm)
 static int nct3018y_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct i2c_client *client = to_i2c_client(dev);
+	struct nct3018y *nct3018y = dev_get_drvdata(dev);
 	unsigned char buf[4] = {0};
-	int err;
+	int err, flags;
+	int restore_flags = 0;
+
+	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL);
+	if (flags < 0) {
+		dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_CTRL.\n");
+		return flags;
+	}
+
+	/* Check and set TWO bit */
+	if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y && !(flags & NCT3018Y_BIT_TWO)) {
+		restore_flags = 1;
+		flags |= NCT3018Y_BIT_TWO;
+		err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+		if (err < 0) {
+			dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+			return err;
+		}
+	}
 
 	buf[0] = bin2bcd(tm->tm_sec);
 	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SC, buf[0]);
@@ -212,6 +234,18 @@ static int nct3018y_rtc_set_time(struct device *dev, struct rtc_time *tm)
 		return -EIO;
 	}
 
+	/* Restore TWO bit */
+	if (restore_flags) {
+		if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y)
+			flags &= ~NCT3018Y_BIT_TWO;
+
+		err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+		if (err < 0) {
+			dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+			return err;
+		}
+	}
+
 	return err;
 }
 
@@ -479,11 +513,17 @@ static int nct3018y_probe(struct i2c_client *client)
 		dev_dbg(&client->dev, "%s: NCT3018Y_BIT_TWO is set\n", __func__);
 	}
 
-	flags = NCT3018Y_BIT_TWO;
-	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
-	if (err < 0) {
-		dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
-		return err;
+	nct3018y->part_num = i2c_smbus_read_byte_data(client, NCT3018Y_REG_PART);
+	if (nct3018y->part_num < 0) {
+		dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_PART.\n");
+		return nct3018y->part_num;
+	} else if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y) {
+		flags = NCT3018Y_BIT_HF;
+		err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
+		if (err < 0) {
+			dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n");
+			return err;
+		}
 	}
 
 	flags = 0;
diff --git a/drivers/rtc/rtc-rv8803.c b/drivers/rtc/rtc-rv8803.c
index 1a3ec1bb5b81..1327251e527c 100644
--- a/drivers/rtc/rtc-rv8803.c
+++ b/drivers/rtc/rtc-rv8803.c
@@ -17,6 +17,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/rtc.h>
+#include <linux/pm_wakeirq.h>
 
 #define RV8803_I2C_TRY_COUNT		4
 
@@ -607,6 +608,28 @@ static int rv8803_regs_configure(struct rv8803_data *rv8803)
 	return 0;
 }
 
+static int rv8803_resume(struct device *dev)
+{
+	struct rv8803_data *rv8803 = dev_get_drvdata(dev);
+
+	if (rv8803->client->irq > 0 && device_may_wakeup(dev))
+		disable_irq_wake(rv8803->client->irq);
+
+	return 0;
+}
+
+static int rv8803_suspend(struct device *dev)
+{
+	struct rv8803_data *rv8803 = dev_get_drvdata(dev);
+
+	if (rv8803->client->irq > 0 && device_may_wakeup(dev))
+		enable_irq_wake(rv8803->client->irq);
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(rv8803_pm_ops, rv8803_suspend, rv8803_resume);
+
 static const struct i2c_device_id rv8803_id[] = {
 	{ "rv8803", rv_8803 },
 	{ "rv8804", rx_8804 },
@@ -683,10 +706,18 @@ static int rv8803_probe(struct i2c_client *client)
 		if (err) {
 			dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
 			client->irq = 0;
+		} else {
+			device_init_wakeup(&client->dev, true);
+			err = dev_pm_set_wake_irq(&client->dev, client->irq);
+			if (err)
+				dev_err(&client->dev, "failed to set wake IRQ\n");
 		}
+	} else {
+		if (device_property_read_bool(&client->dev, "wakeup-source"))
+			device_init_wakeup(&client->dev, true);
+		else
+			clear_bit(RTC_FEATURE_ALARM, rv8803->rtc->features);
 	}
-	if (!client->irq)
-		clear_bit(RTC_FEATURE_ALARM, rv8803->rtc->features);
 
 	if (of_property_read_bool(client->dev.of_node, "epson,vdet-disable"))
 		rv8803->backup |= RX8900_FLAG_VDETOFF;
@@ -737,6 +768,7 @@ static struct i2c_driver rv8803_driver = {
 	.driver = {
 		.name = "rtc-rv8803",
 		.of_match_table = of_match_ptr(rv8803_of_match),
+		.pm = &rv8803_pm_ops,
 	},
 	.probe		= rv8803_probe,
 	.id_table	= rv8803_id,
diff --git a/drivers/rtc/rtc-tps6594.c b/drivers/rtc/rtc-tps6594.c
new file mode 100644
index 000000000000..838ae8562a35
--- /dev/null
+++ b/drivers/rtc/rtc-tps6594.c
@@ -0,0 +1,454 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for tps6594 PMIC
+ *
+ * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/
+ */
+
+#include <linux/bcd.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/property.h>
+#include <linux/rtc.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include <linux/mfd/tps6594.h>
+
+// Total number of RTC registers needed to set time
+#define NUM_TIME_REGS (TPS6594_REG_RTC_WEEKS - TPS6594_REG_RTC_SECONDS + 1)
+
+// Total number of RTC alarm registers
+#define NUM_TIME_ALARM_REGS (NUM_TIME_REGS - 1)
+
+/*
+ * Min and max values supported by 'offset' interface (swapped sign).
+ * After conversion, the values do not exceed the range [-32767, 33767]
+ * which COMP_REG must conform to.
+ */
+#define MIN_OFFSET (-277774)
+#define MAX_OFFSET (277774)
+
+// Number of ticks per hour
+#define TICKS_PER_HOUR (32768 * 3600)
+
+// Multiplier for ppb conversions
+#define PPB_MULT NANO
+
+static int tps6594_rtc_alarm_irq_enable(struct device *dev,
+					unsigned int enabled)
+{
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	u8 val;
+
+	val = enabled ? TPS6594_BIT_IT_ALARM : 0;
+
+	return regmap_update_bits(tps->regmap, TPS6594_REG_RTC_INTERRUPTS,
+				  TPS6594_BIT_IT_ALARM, val);
+}
+
+/* Pulse GET_TIME field of RTC_CTRL_1 to store a timestamp in shadow registers. */
+static int tps6594_rtc_shadow_timestamp(struct device *dev, struct tps6594 *tps)
+{
+	int ret;
+
+	/*
+	 * Set GET_TIME to 0. Next time we set GET_TIME to 1 we will be sure to store
+	 * an up-to-date timestamp.
+	 */
+	ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+				TPS6594_BIT_GET_TIME);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Copy content of RTC registers to shadow registers or latches to read
+	 * a coherent timestamp.
+	 */
+	return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+			       TPS6594_BIT_GET_TIME);
+}
+
+static int tps6594_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	unsigned char rtc_data[NUM_TIME_REGS];
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	int ret;
+
+	// Check if RTC is running.
+	ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS,
+			       TPS6594_BIT_RUN);
+	if (ret < 0)
+		return ret;
+	if (ret == 0)
+		return -EINVAL;
+
+	ret = tps6594_rtc_shadow_timestamp(dev, tps);
+	if (ret < 0)
+		return ret;
+
+	// Read shadowed RTC registers.
+	ret = regmap_bulk_read(tps->regmap, TPS6594_REG_RTC_SECONDS, rtc_data,
+			       NUM_TIME_REGS);
+	if (ret < 0)
+		return ret;
+
+	tm->tm_sec = bcd2bin(rtc_data[0]);
+	tm->tm_min = bcd2bin(rtc_data[1]);
+	tm->tm_hour = bcd2bin(rtc_data[2]);
+	tm->tm_mday = bcd2bin(rtc_data[3]);
+	tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
+	tm->tm_year = bcd2bin(rtc_data[5]) + 100;
+	tm->tm_wday = bcd2bin(rtc_data[6]);
+
+	return 0;
+}
+
+static int tps6594_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	unsigned char rtc_data[NUM_TIME_REGS];
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	int ret;
+
+	rtc_data[0] = bin2bcd(tm->tm_sec);
+	rtc_data[1] = bin2bcd(tm->tm_min);
+	rtc_data[2] = bin2bcd(tm->tm_hour);
+	rtc_data[3] = bin2bcd(tm->tm_mday);
+	rtc_data[4] = bin2bcd(tm->tm_mon + 1);
+	rtc_data[5] = bin2bcd(tm->tm_year - 100);
+	rtc_data[6] = bin2bcd(tm->tm_wday);
+
+	// Stop RTC while updating the RTC time registers.
+	ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+				TPS6594_BIT_STOP_RTC);
+	if (ret < 0)
+		return ret;
+
+	// Update all the time registers in one shot.
+	ret = regmap_bulk_write(tps->regmap, TPS6594_REG_RTC_SECONDS, rtc_data,
+				NUM_TIME_REGS);
+	if (ret < 0)
+		return ret;
+
+	// Start back RTC.
+	return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+			       TPS6594_BIT_STOP_RTC);
+}
+
+static int tps6594_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+	unsigned char alarm_data[NUM_TIME_ALARM_REGS];
+	u32 int_val;
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	int ret;
+
+	ret = regmap_bulk_read(tps->regmap, TPS6594_REG_ALARM_SECONDS,
+			       alarm_data, NUM_TIME_ALARM_REGS);
+	if (ret < 0)
+		return ret;
+
+	alm->time.tm_sec = bcd2bin(alarm_data[0]);
+	alm->time.tm_min = bcd2bin(alarm_data[1]);
+	alm->time.tm_hour = bcd2bin(alarm_data[2]);
+	alm->time.tm_mday = bcd2bin(alarm_data[3]);
+	alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1;
+	alm->time.tm_year = bcd2bin(alarm_data[5]) + 100;
+
+	ret = regmap_read(tps->regmap, TPS6594_REG_RTC_INTERRUPTS, &int_val);
+	if (ret < 0)
+		return ret;
+
+	alm->enabled = int_val & TPS6594_BIT_IT_ALARM;
+
+	return 0;
+}
+
+static int tps6594_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+	unsigned char alarm_data[NUM_TIME_ALARM_REGS];
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	int ret;
+
+	// Disable alarm irq before changing the alarm timestamp.
+	ret = tps6594_rtc_alarm_irq_enable(dev, 0);
+	if (ret)
+		return ret;
+
+	alarm_data[0] = bin2bcd(alm->time.tm_sec);
+	alarm_data[1] = bin2bcd(alm->time.tm_min);
+	alarm_data[2] = bin2bcd(alm->time.tm_hour);
+	alarm_data[3] = bin2bcd(alm->time.tm_mday);
+	alarm_data[4] = bin2bcd(alm->time.tm_mon + 1);
+	alarm_data[5] = bin2bcd(alm->time.tm_year - 100);
+
+	// Update all the alarm registers in one shot.
+	ret = regmap_bulk_write(tps->regmap, TPS6594_REG_ALARM_SECONDS,
+				alarm_data, NUM_TIME_ALARM_REGS);
+	if (ret < 0)
+		return ret;
+
+	if (alm->enabled)
+		ret = tps6594_rtc_alarm_irq_enable(dev, 1);
+
+	return ret;
+}
+
+static int tps6594_rtc_set_calibration(struct device *dev, int calibration)
+{
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	__le16 value;
+	int ret;
+
+	/*
+	 * TPS6594 uses two's complement 16 bit value for compensation of RTC
+	 * crystal inaccuracies. One time every hour when seconds counter
+	 * increments from 0 to 1 compensation value will be added to internal
+	 * RTC counter value.
+	 *
+	 * Valid range for compensation value: [-32767 .. 32767].
+	 */
+	if (calibration < S16_MIN + 1 || calibration > S16_MAX)
+		return -ERANGE;
+
+	value = cpu_to_le16(calibration);
+
+	// Update all the compensation registers in one shot.
+	ret = regmap_bulk_write(tps->regmap, TPS6594_REG_RTC_COMP_LSB, &value,
+				sizeof(value));
+	if (ret < 0)
+		return ret;
+
+	// Enable automatic compensation.
+	return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+			       TPS6594_BIT_AUTO_COMP);
+}
+
+static int tps6594_rtc_get_calibration(struct device *dev, int *calibration)
+{
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	unsigned int ctrl;
+	__le16 value;
+	int ret;
+
+	ret = regmap_read(tps->regmap, TPS6594_REG_RTC_CTRL_1, &ctrl);
+	if (ret < 0)
+		return ret;
+
+	// If automatic compensation is not enabled report back zero.
+	if (!(ctrl & TPS6594_BIT_AUTO_COMP)) {
+		*calibration = 0;
+		return 0;
+	}
+
+	ret = regmap_bulk_read(tps->regmap, TPS6594_REG_RTC_COMP_LSB, &value,
+			       sizeof(value));
+	if (ret < 0)
+		return ret;
+
+	*calibration = le16_to_cpu(value);
+
+	return 0;
+}
+
+static int tps6594_rtc_read_offset(struct device *dev, long *offset)
+{
+	int calibration;
+	s64 tmp;
+	int ret;
+
+	ret = tps6594_rtc_get_calibration(dev, &calibration);
+	if (ret < 0)
+		return ret;
+
+	// Convert from RTC calibration register format to ppb format.
+	tmp = calibration * PPB_MULT;
+
+	if (tmp < 0)
+		tmp -= TICKS_PER_HOUR / 2LL;
+	else
+		tmp += TICKS_PER_HOUR / 2LL;
+	tmp = div_s64(tmp, TICKS_PER_HOUR);
+
+	/*
+	 * SAFETY:
+	 * Computatiion is the reverse operation of the one done in
+	 * `tps6594_rtc_set_offset`. The safety remarks applie here too.
+	 */
+
+	/*
+	 * Offset value operates in negative way, so swap sign.
+	 * See 8.3.10.5, (32768 - COMP_REG).
+	 */
+	*offset = (long)-tmp;
+
+	return 0;
+}
+
+static int tps6594_rtc_set_offset(struct device *dev, long offset)
+{
+	int calibration;
+	s64 tmp;
+
+	// Make sure offset value is within supported range.
+	if (offset < MIN_OFFSET || offset > MAX_OFFSET)
+		return -ERANGE;
+
+	// Convert from ppb format to RTC calibration register format.
+
+	tmp = offset * TICKS_PER_HOUR;
+	if (tmp < 0)
+		tmp -= PPB_MULT / 2LL;
+	else
+		tmp += PPB_MULT / 2LL;
+	tmp = div_s64(tmp, PPB_MULT);
+
+	/*
+	 * SAFETY:
+	 * - tmp = offset * TICK_PER_HOUR :
+	 *	`offset` can't be more than 277774, so `tmp` can't exceed 277774000000000
+	 *	which is lower than the maximum value in an `s64` (2^63-1). No overflow here.
+	 *
+	 * - tmp += TICK_PER_HOUR / 2LL :
+	 *	tmp will have a maximum value of 277774117964800 which is still inferior to 2^63-1.
+	 */
+
+	// Offset value operates in negative way, so swap sign.
+	calibration = (int)-tmp;
+
+	return tps6594_rtc_set_calibration(dev, calibration);
+}
+
+static irqreturn_t tps6594_rtc_interrupt(int irq, void *rtc)
+{
+	struct device *dev = rtc;
+	struct tps6594 *tps = dev_get_drvdata(dev->parent);
+	struct rtc_device *rtc_dev = dev_get_drvdata(dev);
+	int ret;
+	u32 rtc_reg;
+
+	ret = regmap_read(tps->regmap, TPS6594_REG_RTC_STATUS, &rtc_reg);
+	if (ret)
+		return IRQ_NONE;
+
+	rtc_update_irq(rtc_dev, 1, RTC_IRQF | RTC_AF);
+
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops tps6594_rtc_ops = {
+	.read_time = tps6594_rtc_read_time,
+	.set_time = tps6594_rtc_set_time,
+	.read_alarm = tps6594_rtc_read_alarm,
+	.set_alarm = tps6594_rtc_set_alarm,
+	.alarm_irq_enable = tps6594_rtc_alarm_irq_enable,
+	.read_offset = tps6594_rtc_read_offset,
+	.set_offset = tps6594_rtc_set_offset,
+};
+
+static int tps6594_rtc_probe(struct platform_device *pdev)
+{
+	struct tps6594 *tps = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct rtc_device *rtc;
+	int irq;
+	int ret;
+
+	rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
+	if (!rtc)
+		return -ENOMEM;
+
+	rtc = devm_rtc_allocate_device(dev);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	// Enable crystal oscillator.
+	ret = regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_2,
+			      TPS6594_BIT_XTAL_EN);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS,
+			       TPS6594_BIT_RUN);
+	if (ret < 0)
+		return ret;
+	// RTC not running.
+	if (ret == 0) {
+		ret = regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+				      TPS6594_BIT_STOP_RTC);
+		if (ret < 0)
+			return ret;
+
+		/*
+		 * On some boards, a 40 ms delay is needed before BIT_RUN is set.
+		 * 80 ms should provide sufficient margin.
+		 */
+		mdelay(80);
+
+		/*
+		 * RTC should be running now. Check if this is the case.
+		 * If not it might be a missing oscillator.
+		 */
+		ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS,
+				       TPS6594_BIT_RUN);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			return -ENODEV;
+
+		// Stop RTC until first call to `tps6594_rtc_set_time`.
+		ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1,
+					TPS6594_BIT_STOP_RTC);
+		if (ret < 0)
+			return ret;
+	}
+
+	platform_set_drvdata(pdev, rtc);
+
+	irq = platform_get_irq_byname(pdev, TPS6594_IRQ_NAME_ALARM);
+	if (irq < 0)
+		return dev_err_probe(dev, irq, "Failed to get irq\n");
+
+	ret = devm_request_threaded_irq(dev, irq, NULL, tps6594_rtc_interrupt,
+					IRQF_ONESHOT, TPS6594_IRQ_NAME_ALARM,
+					dev);
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "Failed to request_threaded_irq\n");
+
+	ret = device_init_wakeup(dev, true);
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "Failed to init rtc as wakeup source\n");
+
+	rtc->ops = &tps6594_rtc_ops;
+	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	rtc->range_max = RTC_TIMESTAMP_END_2099;
+
+	return devm_rtc_register_device(rtc);
+}
+
+static const struct platform_device_id tps6594_rtc_id_table[] = {
+	{ "tps6594-rtc", },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, tps6594_rtc_id_table);
+
+static struct platform_driver tps6594_rtc_driver = {
+	.probe		= tps6594_rtc_probe,
+	.driver		= {
+		.name	= "tps6594-rtc",
+	},
+	.id_table = tps6594_rtc_id_table,
+};
+
+module_platform_driver(tps6594_rtc_driver);
+MODULE_AUTHOR("Esteban Blanc <eblanc@baylibre.com>");
+MODULE_DESCRIPTION("TPS6594 RTC driver");
+MODULE_LICENSE("GPL");