Merge tag 'rtc-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Subsystem:

   - Remove nvram ABI. There was no complaints about the deprecation for
     the last 3 years.

   - Improve RTC device allocation and registration

   - Now available for ARCH=um

  Drivers:

   - at91rm9200: correction and sam9x60 support

   - ds1307: improve ACPI support

   - mxc: now DT only

   - pcf2127: watchdog support now needs the reset-source property

   - pcf8523: set range

   - rx6110: i2c support"

* tag 'rtc-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (43 commits)
  rtc: pcf2127: only use watchdog when explicitly available
  dt-bindings: rtc: add reset-source property
  rtc: fix RTC removal
  rtc: s3c: Remove dead code related to periodic tick handling
  rtc: s3c: Disable all enable (RTC, tick) bits in the probe
  rtc: ep93xx: Fix NULL pointer dereference in ep93xx_rtc_read_time
  rtc: test: remove debug message
  rtc: mxc{,_v2}: enable COMPILE_TEST
  rtc: enable RTC framework on ARCH=um
  rtc: pcf8523: use BIT
  rtc: pcf8523: set range
  rtc: pcf8523: switch to devm_rtc_allocate_device
  rtc: destroy mutex when releasing the device
  rtc: shrink devm_rtc_allocate_device()
  rtc: rework rtc_register_device() resource management
  rtc: nvmem: emit an error message when nvmem registration fails
  rtc: add devm_ prefix to rtc_nvmem_register()
  rtc: nvmem: remove nvram ABI
  Documentation: list RTC devres helpers in devres.rst
  rtc: omap: use devm_pinctrl_register()
  ...

Documentation/devicetree/bindings/rtc/rtc.yaml

@@ -63,6 +63,11 @@ properties:
     description:
       Enables wake up of host system on alarm.
 
+  reset-source:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      The RTC is able to reset the machine.
+
 additionalProperties: true
 
 ...

Documentation/driver-api/driver-model/devres.rst

@@ -411,6 +411,12 @@ RESET
   devm_reset_control_get()
   devm_reset_controller_register()
 
+RTC
+  devm_rtc_device_register()
+  devm_rtc_allocate_device()
+  devm_rtc_register_device()
+  devm_rtc_nvmem_register()
+
 SERDEV
   devm_serdev_device_open()
 

MAINTAINERS

@@ -1183,7 +1183,7 @@ F:	Documentation/devicetree/bindings/interrupt-controller/google,goldfish-pic.tx
 F:	drivers/irqchip/irq-goldfish-pic.c
 
 ANDROID GOLDFISH RTC DRIVER
-M:	Miodrag Dinic <miodrag.dinic@mips.com>
+M:	Jiaxun Yang <jiaxun.yang@flygoat.com>
 S:	Supported
 F:	Documentation/devicetree/bindings/rtc/google,goldfish-rtc.txt
 F:	drivers/rtc/rtc-goldfish.c

arch/alpha/kernel/rtc.c

@@ -216,6 +216,6 @@ alpha_rtc_init(void)
 		rtc->ops = &remote_rtc_ops;
 #endif
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 device_initcall(alpha_rtc_init);

drivers/mfd/menelaus.c

@@ -1119,7 +1119,7 @@ static inline void menelaus_rtc_init(struct menelaus_chip *m)
 		menelaus_write_reg(MENELAUS_RTC_CTRL, m->rtc_control);
 	}
 
-	err = rtc_register_device(m->rtc);
+	err = devm_rtc_register_device(m->rtc);
 	if (err) {
 		if (alarm) {
 			menelaus_remove_irq_work(MENELAUS_RTCALM_IRQ);

drivers/rtc/Kconfig

@@ -13,7 +13,7 @@ config RTC_MC146818_LIB
 menuconfig RTC_CLASS
 	bool "Real Time Clock"
 	default n
-	depends on !S390 && !UML
+	depends on !S390
 	select RTC_LIB
 	help
 	  Generic RTC class support. If you say yes here, you will
@@ -817,15 +817,6 @@ config RTC_DRV_RX4581
 	  This driver can also be built as a module. If so the module
 	  will be called rtc-rx4581.
 
-config RTC_DRV_RX6110
-	tristate "Epson RX-6110"
-	select REGMAP_SPI
-	help
-	  If you say yes here you will get support for the Epson RX-6610.
-
-	  This driver can also be built as a module. If so the module
-	  will be called rtc-rx6110.
-
 config RTC_DRV_RS5C348
 	tristate "Ricoh RS5C348A/B"
 	help
@@ -936,6 +927,17 @@ config RTC_DRV_RV3029_HWMON
 	  Say Y here if you want to expose temperature sensor data on
 	  rtc-rv3029.
 
+config RTC_DRV_RX6110
+	tristate "Epson RX-6110"
+	depends on RTC_I2C_AND_SPI
+	select REGMAP_SPI if SPI_MASTER
+	select REGMAP_I2C if I2C
+	help
+	  If you say yes here you will get support for the Epson RX-6110.
+
+	  This driver can also be built as a module. If so the module
+	  will be called rtc-rx6110.
+
 comment "Platform RTC drivers"
 
 # this 'CMOS' RTC driver is arch dependent because it requires
@@ -1017,6 +1019,7 @@ config RTC_DRV_DS1553
 
 config RTC_DRV_DS1685_FAMILY
 	tristate "Dallas/Maxim DS1685 Family"
+	depends on HAS_IOMEM
 	help
 	  If you say yes here you get support for the Dallas/Maxim DS1685
 	  family of real time chips.  This family includes the DS1685/DS1687,
@@ -1150,6 +1153,7 @@ config RTC_DRV_STK17TA8
 
 config RTC_DRV_M48T86
 	tristate "ST M48T86/Dallas DS12887"
+	depends on HAS_IOMEM
 	help
 	  If you say Y here you will get support for the
 	  ST M48T86 and Dallas DS12887 RTC chips.
@@ -1752,7 +1756,9 @@ config RTC_DRV_LOONGSON1
 
 config RTC_DRV_MXC
 	tristate "Freescale MXC Real Time Clock"
-	depends on ARCH_MXC
+	depends on ARCH_MXC || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
 	help
 	   If you say yes here you get support for the Freescale MXC
 	   RTC module.
@@ -1762,7 +1768,9 @@ config RTC_DRV_MXC
 
 config RTC_DRV_MXC_V2
 	tristate "Freescale MXC Real Time Clock for i.MX53"
-	depends on ARCH_MXC
+	depends on ARCH_MXC || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
 	help
 	   If you say yes here you get support for the Freescale MXC
 	   SRTC module in i.MX53 processor.
@@ -1935,7 +1943,6 @@ config RTC_DRV_HID_SENSOR_TIME
 config RTC_DRV_GOLDFISH
 	tristate "Goldfish Real Time Clock"
 	depends on OF && HAS_IOMEM
-	depends on GOLDFISH || COMPILE_TEST
 	help
 	  Say yes to enable RTC driver for the Goldfish based virtual platform.
 

drivers/rtc/class.c

@@ -28,6 +28,7 @@ static void rtc_device_release(struct device *dev)
 	struct rtc_device *rtc = to_rtc_device(dev);
 
 	ida_simple_remove(&rtc_ida, rtc->id);
+	mutex_destroy(&rtc->ops_lock);
 	kfree(rtc);
 }
 
@@ -326,8 +327,10 @@ static void rtc_device_get_offset(struct rtc_device *rtc)
  *
  * @rtc: the RTC class device to destroy
  */
-static void rtc_device_unregister(struct rtc_device *rtc)
+static void devm_rtc_unregister_device(void *data)
 {
+	struct rtc_device *rtc = data;
+
 	mutex_lock(&rtc->ops_lock);
 	/*
 	 * Remove innards of this RTC, then disable it, before
@@ -337,60 +340,43 @@ static void rtc_device_unregister(struct rtc_device *rtc)
 	cdev_device_del(&rtc->char_dev, &rtc->dev);
 	rtc->ops = NULL;
 	mutex_unlock(&rtc->ops_lock);
-	put_device(&rtc->dev);
 }
 
-static void devm_rtc_release_device(struct device *dev, void *res)
+static void devm_rtc_release_device(void *res)
 {
-	struct rtc_device *rtc = *(struct rtc_device **)res;
+	struct rtc_device *rtc = res;
 
-	rtc_nvmem_unregister(rtc);
-
-	if (rtc->registered)
-		rtc_device_unregister(rtc);
-	else
-		put_device(&rtc->dev);
+	put_device(&rtc->dev);
 }
 
 struct rtc_device *devm_rtc_allocate_device(struct device *dev)
 {
-	struct rtc_device **ptr, *rtc;
+	struct rtc_device *rtc;
 	int id, err;
 
 	id = rtc_device_get_id(dev);
 	if (id < 0)
 		return ERR_PTR(id);
 
-	ptr = devres_alloc(devm_rtc_release_device, sizeof(*ptr), GFP_KERNEL);
-	if (!ptr) {
-		err = -ENOMEM;
-		goto exit_ida;
-	}
-
 	rtc = rtc_allocate_device();
 	if (!rtc) {
-		err = -ENOMEM;
-		goto exit_devres;
+		ida_simple_remove(&rtc_ida, id);
+		return ERR_PTR(-ENOMEM);
 	}
 
-	*ptr = rtc;
-	devres_add(dev, ptr);
-
 	rtc->id = id;
 	rtc->dev.parent = dev;
 	dev_set_name(&rtc->dev, "rtc%d", id);
 
-	return rtc;
+	err = devm_add_action_or_reset(dev, devm_rtc_release_device, rtc);
+	if (err)
+		return ERR_PTR(err);
 
-exit_devres:
-	devres_free(ptr);
-exit_ida:
-	ida_simple_remove(&rtc_ida, id);
-	return ERR_PTR(err);
+	return rtc;
 }
 EXPORT_SYMBOL_GPL(devm_rtc_allocate_device);
 
-int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
+int __devm_rtc_register_device(struct module *owner, struct rtc_device *rtc)
 {
 	struct rtc_wkalrm alrm;
 	int err;
@@ -420,7 +406,6 @@ int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
 
 	rtc_proc_add_device(rtc);
 
-	rtc->registered = true;
 	dev_info(rtc->dev.parent, "registered as %s\n",
 		 dev_name(&rtc->dev));
 
@@ -429,9 +414,10 @@ int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
 		rtc_hctosys(rtc);
 #endif
 
-	return 0;
+	return devm_add_action_or_reset(rtc->dev.parent,
+					devm_rtc_unregister_device, rtc);
 }
-EXPORT_SYMBOL_GPL(__rtc_register_device);
+EXPORT_SYMBOL_GPL(__devm_rtc_register_device);
 
 /**
  * devm_rtc_device_register - resource managed rtc_device_register()
@@ -461,7 +447,7 @@ struct rtc_device *devm_rtc_device_register(struct device *dev,
 
 	rtc->ops = ops;
 
-	err = __rtc_register_device(owner, rtc);
+	err = __devm_rtc_register_device(owner, rtc);
 	if (err)
 		return ERR_PTR(err);
 

drivers/rtc/nvmem.c

@@ -9,99 +9,22 @@
 #include <linux/types.h>
 #include <linux/nvmem-consumer.h>
 #include <linux/rtc.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
 
-/*
- * Deprecated ABI compatibility, this should be removed at some point
- */
-
-static const char nvram_warning[] = "Deprecated ABI, please use nvmem";
-
-static ssize_t
-rtc_nvram_read(struct file *filp, struct kobject *kobj,
-	       struct bin_attribute *attr,
-	       char *buf, loff_t off, size_t count)
-{
-	dev_warn_once(kobj_to_dev(kobj), nvram_warning);
-
-	return nvmem_device_read(attr->private, off, count, buf);
-}
-
-static ssize_t
-rtc_nvram_write(struct file *filp, struct kobject *kobj,
-		struct bin_attribute *attr,
-		char *buf, loff_t off, size_t count)
-{
-	dev_warn_once(kobj_to_dev(kobj), nvram_warning);
-
-	return nvmem_device_write(attr->private, off, count, buf);
-}
-
-static int rtc_nvram_register(struct rtc_device *rtc,
-			      struct nvmem_device *nvmem, size_t size)
-{
-	int err;
-
-	rtc->nvram = kzalloc(sizeof(*rtc->nvram), GFP_KERNEL);
-	if (!rtc->nvram)
-		return -ENOMEM;
-
-	rtc->nvram->attr.name = "nvram";
-	rtc->nvram->attr.mode = 0644;
-	rtc->nvram->private = nvmem;
-
-	sysfs_bin_attr_init(rtc->nvram);
-
-	rtc->nvram->read = rtc_nvram_read;
-	rtc->nvram->write = rtc_nvram_write;
-	rtc->nvram->size = size;
-
-	err = sysfs_create_bin_file(&rtc->dev.parent->kobj,
-				    rtc->nvram);
-	if (err) {
-		kfree(rtc->nvram);
-		rtc->nvram = NULL;
-	}
-
-	return err;
-}
-
-static void rtc_nvram_unregister(struct rtc_device *rtc)
-{
-	sysfs_remove_bin_file(&rtc->dev.parent->kobj, rtc->nvram);
-	kfree(rtc->nvram);
-	rtc->nvram = NULL;
-}
-
-/*
- * New ABI, uses nvmem
- */
-int rtc_nvmem_register(struct rtc_device *rtc,
+int devm_rtc_nvmem_register(struct rtc_device *rtc,
 		       struct nvmem_config *nvmem_config)
 {
+	struct device *dev = rtc->dev.parent;
 	struct nvmem_device *nvmem;
 
 	if (!nvmem_config)
 		return -ENODEV;
 
-	nvmem_config->dev = rtc->dev.parent;
+	nvmem_config->dev = dev;
 	nvmem_config->owner = rtc->owner;
-	nvmem = devm_nvmem_register(rtc->dev.parent, nvmem_config);
+	nvmem = devm_nvmem_register(dev, nvmem_config);
 	if (IS_ERR(nvmem))
-		return PTR_ERR(nvmem);
+		dev_err(dev, "failed to register nvmem device for RTC\n");
 
-	/* Register the old ABI */
-	if (rtc->nvram_old_abi)
-		rtc_nvram_register(rtc, nvmem, nvmem_config->size);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(rtc_nvmem_register);
-
-void rtc_nvmem_unregister(struct rtc_device *rtc)
-{
-	/* unregister the old ABI */
-	if (rtc->nvram)
-		rtc_nvram_unregister(rtc);
+	return PTR_ERR_OR_ZERO(nvmem);
 }
+EXPORT_SYMBOL_GPL(devm_rtc_nvmem_register);

drivers/rtc/rtc-88pm80x.c

@@ -294,7 +294,7 @@ static int pm80x_rtc_probe(struct platform_device *pdev)
 	info->rtc_dev->ops = &pm80x_rtc_ops;
 	info->rtc_dev->range_max = U32_MAX;
 
-	ret = rtc_register_device(info->rtc_dev);
+	ret = devm_rtc_register_device(info->rtc_dev);
 	if (ret)
 		goto out_rtc;
 

drivers/rtc/rtc-88pm860x.c

@@ -307,7 +307,7 @@ static int pm860x_rtc_probe(struct platform_device *pdev)
 	info->rtc_dev->ops = &pm860x_rtc_ops;
 	info->rtc_dev->range_max = U32_MAX;
 
-	ret = rtc_register_device(info->rtc_dev);
+	ret = devm_rtc_register_device(info->rtc_dev);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ab-b5ze-s3.c

@@ -892,7 +892,7 @@ static int abb5zes3_probe(struct i2c_client *client,
 		}
 	}
 
-	ret = rtc_register_device(data->rtc);
+	ret = devm_rtc_register_device(data->rtc);
 
 err:
 	if (ret && data->irq)

drivers/rtc/rtc-ab-eoz9.c

@@ -420,7 +420,7 @@ static int abeoz9_probe(struct i2c_client *client,
 	data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	data->rtc->range_max = RTC_TIMESTAMP_END_2099;
 
-	ret = rtc_register_device(data->rtc);
+	ret = devm_rtc_register_device(data->rtc);
 	if (ret)
 		return ret;
 

drivers/rtc/rtc-ab3100.c

@@ -238,7 +238,7 @@ static int __init ab3100_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, rtc);
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static struct platform_driver ab3100_rtc_driver = {

drivers/rtc/rtc-ab8500.c

@@ -404,7 +404,7 @@ static int ab8500_rtc_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
-	return rtc_register_device(rtc);
+	return devm_rtc_register_device(rtc);
 }
 
 static int ab8500_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-abx80x.c

@@ -851,7 +851,7 @@ static int abx80x_probe(struct i2c_client *client,
 		return err;
 	}
 
-	return rtc_register_device(priv->rtc);
+	return devm_rtc_register_device(priv->rtc);
 }
 
 static const struct i2c_device_id abx80x_id[] = {

drivers/rtc/rtc-ac100.c

@@ -610,7 +610,7 @@ static int ac100_rtc_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	return rtc_register_device(chip->rtc);
+	return devm_rtc_register_device(chip->rtc);
 }
 
 static int ac100_rtc_remove(struct platform_device *pdev)

drivers/rtc/rtc-armada38x.c

@@ -556,7 +556,7 @@ static __init int armada38x_rtc_probe(struct platform_device *pdev)
 
 	rtc->rtc_dev->range_max = U32_MAX;
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 #ifdef CONFIG_PM_SLEEP

drivers/rtc/rtc-aspeed.c

@@ -104,7 +104,7 @@ static int aspeed_rtc_probe(struct platform_device *pdev)
 	rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_1900;
 	rtc->rtc_dev->range_max = 38814989399LL; /* 3199-12-31 23:59:59 */
 
-	return rtc_register_device(rtc->rtc_dev);
+	return devm_rtc_register_device(rtc->rtc_dev);
 }
 
 static const struct of_device_id aspeed_rtc_match[] = {

drivers/rtc/rtc-at91rm9200.c

@@ -36,6 +36,10 @@
 #define		AT91_RTC_UPDCAL		BIT(1)		/* Update Request Calendar Register */
 
 #define	AT91_RTC_MR		0x04			/* Mode Register */
+#define		AT91_RTC_HRMOD		BIT(0)		/* 12/24 hour mode */
+#define		AT91_RTC_NEGPPM		BIT(4)		/* Negative PPM correction */
+#define		AT91_RTC_CORRECTION	GENMASK(14, 8)	/* Slow clock correction */
+#define		AT91_RTC_HIGHPPM	BIT(15)		/* High PPM correction */
 
 #define	AT91_RTC_TIMR		0x08			/* Time Register */
 #define		AT91_RTC_SEC		GENMASK(6, 0)	/* Current Second */
@@ -77,6 +81,9 @@
 #define		AT91_RTC_NVTIMALR	BIT(2)		/* Non valid Time Alarm */
 #define		AT91_RTC_NVCALALR	BIT(3)		/* Non valid Calendar Alarm */
 
+#define AT91_RTC_CORR_DIVIDEND		3906000
+#define AT91_RTC_CORR_LOW_RATIO		20
+
 #define at91_rtc_read(field) \
 	readl_relaxed(at91_rtc_regs + field)
 #define at91_rtc_write(field, val) \
@@ -84,6 +91,7 @@
 
 struct at91_rtc_config {
 	bool use_shadow_imr;
+	bool has_correction;
 };
 
 static const struct at91_rtc_config *at91_rtc_config;
@@ -293,6 +301,75 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 	return 0;
 }
 
+static int at91_rtc_readoffset(struct device *dev, long *offset)
+{
+	u32 mr = at91_rtc_read(AT91_RTC_MR);
+	long val = FIELD_GET(AT91_RTC_CORRECTION, mr);
+
+	if (!val) {
+		*offset = 0;
+		return 0;
+	}
+
+	val++;
+
+	if (!(mr & AT91_RTC_NEGPPM))
+		val = -val;
+
+	if (!(mr & AT91_RTC_HIGHPPM))
+		val *= AT91_RTC_CORR_LOW_RATIO;
+
+	*offset = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, val);
+
+	return 0;
+}
+
+static int at91_rtc_setoffset(struct device *dev, long offset)
+{
+	long corr;
+	u32 mr;
+
+	if (offset > AT91_RTC_CORR_DIVIDEND / 2)
+		return -ERANGE;
+	if (offset < -AT91_RTC_CORR_DIVIDEND / 2)
+		return -ERANGE;
+
+	mr = at91_rtc_read(AT91_RTC_MR);
+	mr &= ~(AT91_RTC_NEGPPM | AT91_RTC_CORRECTION | AT91_RTC_HIGHPPM);
+
+	if (offset > 0)
+		mr |= AT91_RTC_NEGPPM;
+	else
+		offset = -offset;
+
+	/* offset less than 764 ppb, disable correction*/
+	if (offset < 764) {
+		at91_rtc_write(AT91_RTC_MR, mr & ~AT91_RTC_NEGPPM);
+
+		return 0;
+	}
+
+	/*
+	 * 29208 ppb is the perfect cutoff between low range and high range
+	 * low range values are never better than high range value after that.
+	 */
+	if (offset < 29208) {
+		corr = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, offset * AT91_RTC_CORR_LOW_RATIO);
+	} else {
+		corr = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, offset);
+		mr |= AT91_RTC_HIGHPPM;
+	}
+
+	if (corr > 128)
+		corr = 128;
+
+	mr |= FIELD_PREP(AT91_RTC_CORRECTION, corr - 1);
+
+	at91_rtc_write(AT91_RTC_MR, mr);
+
+	return 0;
+}
+
 /*
  * IRQ handler for the RTC
  */
@@ -343,6 +420,10 @@ static const struct at91_rtc_config at91sam9x5_config = {
 	.use_shadow_imr	= true,
 };
 
+static const struct at91_rtc_config sama5d4_config = {
+	.has_correction = true,
+};
+
 static const struct of_device_id at91_rtc_dt_ids[] = {
 	{
 		.compatible = "atmel,at91rm9200-rtc",
@@ -352,10 +433,13 @@ static const struct of_device_id at91_rtc_dt_ids[] = {
 		.data = &at91sam9x5_config,
 	}, {
 		.compatible = "atmel,sama5d4-rtc",
-		.data = &at91rm9200_config,
+		.data = &sama5d4_config,
 	}, {
 		.compatible = "atmel,sama5d2-rtc",
-		.data = &at91rm9200_config,
+		.data = &sama5d4_config,
+	}, {
+		.compatible = "microchip,sam9x60-rtc",
+		.data = &sama5d4_config,
 	}, {
 		/* sentinel */
 	}
@@ -370,6 +454,16 @@ static const struct rtc_class_ops at91_rtc_ops = {
 	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
 };
 
+static const struct rtc_class_ops sama5d4_rtc_ops = {
+	.read_time	= at91_rtc_readtime,
+	.set_time	= at91_rtc_settime,
+	.read_alarm	= at91_rtc_readalarm,
+	.set_alarm	= at91_rtc_setalarm,
+	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
+	.set_offset	= at91_rtc_setoffset,
+	.read_offset	= at91_rtc_readoffset,
+};
+
 /*
  * Initialize and install RTC driver
  */
@@ -416,7 +510,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
 	}
 
 	at91_rtc_write(AT91_RTC_CR, 0);
-	at91_rtc_write(AT91_RTC_MR, 0);		/* 24 hour mode */
+	at91_rtc_write(AT91_RTC_MR, at91_rtc_read(AT91_RTC_MR) & ~AT91_RTC_HRMOD);
 
 	/* Disable all interrupts */
 	at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
@@ -437,10 +531,14 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
 	if (!device_can_wakeup(&pdev->dev))
 		device_init_wakeup(&pdev->dev, 1);
 
-	rtc->ops = &at91_rtc_ops;
+	if (at91_rtc_config->has_correction)
+		rtc->ops = &sama5d4_rtc_ops;
+	else
+		rtc->ops = &at91_rtc_ops;
+
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_1900;
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
-	ret = rtc_register_device(rtc);
+	ret = devm_rtc_register_device(rtc);
 	if (ret)
 		goto err_clk;
 

drivers/rtc/rtc-at91sam9.c

@@ -431,7 +431,7 @@ static int at91_rtc_probe(struct platform_device *pdev)
 		dev_warn(&pdev->dev, "%s: SET TIME!\n",
 			 dev_name(&rtc->rtcdev->dev));
 
-	return rtc_register_device(rtc->rtcdev);
+	return devm_rtc_register_device(rtc->rtcdev);
 
 err_clk:
 	clk_disable_unprepare(rtc->sclk);