Merge tag 'rtc-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
"Core:
- fix module reference count in rtc-proc
- Replace simple_strtoul by kstrtoul

New driver:
- Epson RX8010SJ

Subsystem wide cleanups:
- use %ph for short hex dumps
- constify *_chip_ops structures

Drivers:
- abx80x: Microcrystal rv1805 support, alarm support
- cmos: prevent kernel warning on IRQ flags mismatch
- s5m: various cleanups
- rv8803: rx8900 compatibility, small error path fix
- sunxi: various cleanups
- lpc32xx: remove irq > NR_IRQS check from probe()
- imxdi: fix spelling mistake in warning message
- ds1685: don't try to micromanage sysfs output size
- da9063: avoid writing undefined data to rtc
- gemini: Remove unnecessary platform_set_drvdata()
- efi: add efi_procfs in efi_rtc_ops
- pcf8523: refuse to write dates later than 2099"

* tag 'rtc-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (24 commits)
rtc: cmos: prevent kernel warning on IRQ flags mismatch
rtc: rtc-ds2404: constify ds2404_chip_ops structures
rtc: s5m: Make register configuration per S2MPS device to remove exceptions
rtc: s5m: Add separate field for storing auto-cleared mask in register config
rtc: s5m: Cleanup by removing useless 'rtc' prefix from fields
rtc: Replace simple_strtoul by kstrtoul
rtc: abx80x: add alarm support
rtc: abx80x: Add Microcrystal rv1805 support
rtc: v3020: constify v3020_chip_ops structures
rtc: rv8803: Extend compatibility with the rx8900
rtc: rv8803: fix handling return value of i2c_smbus_read_byte_data
rtc: Add Epson RX8010SJ RTC driver
rtc: lpc32xx: remove irq > NR_IRQS check from probe()
rtc: imxdi: fix spelling mistake in warning message
rtc: ds1685: don't try to micromanage sysfs output size
rtc: use %ph for short hex dumps
rtc: da9063: avoid writing undefined data to rtc
rtc: sunxi: use of_device_get_match_data
rtc: sunxi: constify the data_year_param structure
rtc: sunxi: fix signedness issues
...

drivers/rtc/Kconfig

···
 	  This driver can also be built as a module. If so the module
 	  will be called rtc-fm3130.
 
+config RTC_DRV_RX8010
+	tristate "Epson RX8010SJ"
+	depends on I2C
+	help
+	  If you say yes here you get support for the Epson RX8010SJ RTC
+	  chip.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-rx8010.
+
 config RTC_DRV_RX8581
 	tristate "Epson RX-8581"
 	help

drivers/rtc/Makefile

···
 obj-$(CONFIG_RTC_DRV_RV3029C2)	+= rtc-rv3029c2.o
 obj-$(CONFIG_RTC_DRV_RV8803)	+= rtc-rv8803.o
 obj-$(CONFIG_RTC_DRV_RX4581)	+= rtc-rx4581.o
+obj-$(CONFIG_RTC_DRV_RX8010)	+= rtc-rx8010.o
 obj-$(CONFIG_RTC_DRV_RX8025)	+= rtc-rx8025.o
 obj-$(CONFIG_RTC_DRV_RX8581)	+= rtc-rx8581.o
 obj-$(CONFIG_RTC_DRV_S35390A)	+= rtc-s35390a.o

drivers/rtc/rtc-abx80x.c

···
 #define ABX8XX_REG_YR		0x06
 #define ABX8XX_REG_WD		0x07
 
+#define ABX8XX_REG_AHTH		0x08
+#define ABX8XX_REG_ASC		0x09
+#define ABX8XX_REG_AMN		0x0a
+#define ABX8XX_REG_AHR		0x0b
+#define ABX8XX_REG_ADA		0x0c
+#define ABX8XX_REG_AMO		0x0d
+#define ABX8XX_REG_AWD		0x0e
+
+#define ABX8XX_REG_STATUS	0x0f
+#define ABX8XX_STATUS_AF	BIT(2)
+
 #define ABX8XX_REG_CTRL1	0x10
 #define ABX8XX_CTRL_WRITE	BIT(0)
+#define ABX8XX_CTRL_ARST	BIT(2)
 #define ABX8XX_CTRL_12_24	BIT(6)
+
+#define ABX8XX_REG_IRQ		0x12
+#define ABX8XX_IRQ_AIE		BIT(2)
+#define ABX8XX_IRQ_IM_1_4	(0x3 << 5)
+
+#define ABX8XX_REG_CD_TIMER_CTL	0x18
 
 #define ABX8XX_REG_CFG_KEY	0x1f
 #define ABX8XX_CFG_KEY_MISC	0x9d
···
 	[AB1805] = {.pn = 0x1805, .has_tc = true},
 	[ABX80X] = {.pn = 0}
 };
-
-static struct i2c_driver abx80x_driver;
 
 static int abx80x_enable_trickle_charger(struct i2c_client *client,
 					 u8 trickle_cfg)
···
 	return 0;
 }
 
+static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
+{
+	struct i2c_client *client = dev_id;
+	struct rtc_device *rtc = i2c_get_clientdata(client);
+	int status;
+
+	status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+	if (status < 0)
+		return IRQ_NONE;
+
+	if (status & ABX8XX_STATUS_AF)
+		rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);
+
+	i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
+
+	return IRQ_HANDLED;
+}
+
+static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	unsigned char buf[7];
+
+	int irq_mask, err;
+
+	if (client->irq <= 0)
+		return -EINVAL;
+
+	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
+					    sizeof(buf), buf);
+	if (err)
+		return err;
+
+	irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
+	if (irq_mask < 0)
+		return irq_mask;
+
+	t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
+	t->time.tm_min = bcd2bin(buf[1] & 0x7F);
+	t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
+	t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
+	t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
+	t->time.tm_wday = buf[5] & 0x7;
+
+	t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
+	t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;
+
+	return err;
+}
+
+static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	u8 alarm[6];
+	int err;
+
+	if (client->irq <= 0)
+		return -EINVAL;
+
+	alarm[0] = 0x0;
+	alarm[1] = bin2bcd(t->time.tm_sec);
+	alarm[2] = bin2bcd(t->time.tm_min);
+	alarm[3] = bin2bcd(t->time.tm_hour);
+	alarm[4] = bin2bcd(t->time.tm_mday);
+	alarm[5] = bin2bcd(t->time.tm_mon + 1);
+
+	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
+					     sizeof(alarm), alarm);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to write alarm registers\n");
+		return -EIO;
+	}
+
+	if (t->enabled) {
+		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+						(ABX8XX_IRQ_IM_1_4 |
+						 ABX8XX_IRQ_AIE));
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int err;
+
+	if (enabled)
+		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+						(ABX8XX_IRQ_IM_1_4 |
+						 ABX8XX_IRQ_AIE));
+	else
+		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+						ABX8XX_IRQ_IM_1_4);
+	return err;
+}
+
 static const struct rtc_class_ops abx80x_rtc_ops = {
 	.read_time	= abx80x_rtc_read_time,
 	.set_time	= abx80x_rtc_set_time,
+	.read_alarm	= abx80x_read_alarm,
+	.set_alarm	= abx80x_set_alarm,
+	.alarm_irq_enable = abx80x_alarm_irq_enable,
 };
 
 static int abx80x_dt_trickle_cfg(struct device_node *np)
···
 	}
 
 	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
-					((data & ~ABX8XX_CTRL_12_24) |
+					((data & ~(ABX8XX_CTRL_12_24 |
+						   ABX8XX_CTRL_ARST)) |
 					 ABX8XX_CTRL_WRITE));
 	if (err < 0) {
 		dev_err(&client->dev, "Unable to write control register\n");
···
 		abx80x_enable_trickle_charger(client, trickle_cfg);
 	}
 
-	rtc = devm_rtc_device_register(&client->dev, abx80x_driver.driver.name,
+	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
+					BIT(2));
+	if (err)
+		return err;
+
+	rtc = devm_rtc_device_register(&client->dev, "abx8xx",
 				       &abx80x_rtc_ops, THIS_MODULE);
 
 	if (IS_ERR(rtc))
 		return PTR_ERR(rtc);
 
 	i2c_set_clientdata(client, rtc);
+
+	if (client->irq > 0) {
+		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
+		err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
+						abx80x_handle_irq,
+						IRQF_SHARED | IRQF_ONESHOT,
+						"abx8xx",
+						client);
+		if (err) {
+			dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
+			client->irq = 0;
+		}
+	}
 
 	return 0;
 }
···
 	{ "ab1803", AB1803 },
 	{ "ab1804", AB1804 },
 	{ "ab1805", AB1805 },
+	{ "rv1805", AB1805 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, abx80x_id);

drivers/rtc/rtc-cmos.c

···
 			rtc_cmos_int_handler = cmos_interrupt;
 
 		retval = request_irq(rtc_irq, rtc_cmos_int_handler,
-				0, dev_name(&cmos_rtc.rtc->dev),
+				IRQF_SHARED, dev_name(&cmos_rtc.rtc->dev),
 				cmos_rtc.rtc);
 		if (retval < 0) {
 			dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);

drivers/rtc/rtc-da9063.c

···
 {
 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
 
-	data[RTC_SEC] &= ~config->rtc_count_sec_mask;
-	data[RTC_SEC] |= tm->tm_sec & config->rtc_count_sec_mask;
-
-	data[RTC_MIN] &= ~config->rtc_count_min_mask;
-	data[RTC_MIN] |= tm->tm_min & config->rtc_count_min_mask;
-
-	data[RTC_HOUR] &= ~config->rtc_count_hour_mask;
-	data[RTC_HOUR] |= tm->tm_hour & config->rtc_count_hour_mask;
-
-	data[RTC_DAY] &= ~config->rtc_count_day_mask;
-	data[RTC_DAY] |= tm->tm_mday & config->rtc_count_day_mask;
-
-	data[RTC_MONTH] &= ~config->rtc_count_month_mask;
-	data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
+	data[RTC_SEC]   = tm->tm_sec & config->rtc_count_sec_mask;
+	data[RTC_MIN]   = tm->tm_min & config->rtc_count_min_mask;
+	data[RTC_HOUR]  = tm->tm_hour & config->rtc_count_hour_mask;
+	data[RTC_DAY]   = tm->tm_mday & config->rtc_count_day_mask;
+	data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
 				config->rtc_count_month_mask;
-
-	data[RTC_YEAR] &= ~config->rtc_count_year_mask;
-	data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
+	data[RTC_YEAR]  = YEARS_TO_DA9063(tm->tm_year) &
 				config->rtc_count_year_mask;
 }
 

drivers/rtc/rtc-ds1305.c

···
 	if (status < 0)
 		return status;
 
-	dev_vdbg(dev, "%s: %02x %02x %02x, %02x %02x %02x %02x\n",
-		"read", buf[0], buf[1], buf[2], buf[3],
-		buf[4], buf[5], buf[6]);
+	dev_vdbg(dev, "%s: %3ph, %4ph\n", "read", &buf[0], &buf[3]);
 
 	/* Decode the registers */
 	time->tm_sec = bcd2bin(buf[DS1305_SEC]);
···
 	*bp++ = bin2bcd(time->tm_mon + 1);
 	*bp++ = bin2bcd(time->tm_year - 100);
 
-	dev_dbg(dev, "%s: %02x %02x %02x, %02x %02x %02x %02x\n",
-		"write", buf[1], buf[2], buf[3],
-		buf[4], buf[5], buf[6], buf[7]);
+	dev_dbg(dev, "%s: %3ph, %4ph\n", "write", &buf[1], &buf[4]);
 
 	/* use write-then-read since dma from stack is nonportable */
 	return spi_write_then_read(ds1305->spi, buf, sizeof(buf),

drivers/rtc/rtc-ds1307.c

···
 		return -EIO;
 	}
 
-	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
-			"alarm read",
-			ds1307->regs[0], ds1307->regs[1],
-			ds1307->regs[2], ds1307->regs[3],
-			ds1307->regs[4], ds1307->regs[5],
-			ds1307->regs[6], ds1307->regs[7],
-			ds1307->regs[8]);
+	dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
+		&ds1307->regs[0], &ds1307->regs[4], &ds1307->regs[7]);
 
 	/*
 	 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
···
 	control = ds1307->regs[7];
 	status = ds1307->regs[8];
 
-	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
-			"alarm set (old status)",
-			ds1307->regs[0], ds1307->regs[1],
-			ds1307->regs[2], ds1307->regs[3],
-			ds1307->regs[4], ds1307->regs[5],
-			ds1307->regs[6], control, status);
+	dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
+		&ds1307->regs[0], &ds1307->regs[4], control, status);
 
 	/* set ALARM1, using 24 hour and day-of-month modes */
 	buf[0] = bin2bcd(t->time.tm_sec);

drivers/rtc/rtc-ds1685.c

···
 	   "Periodic Rate\t: %s\n"
 	   "SQW Freq\t: %s\n"
 #ifdef CONFIG_RTC_DS1685_PROC_REGS
-	   "Serial #\t: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n"
+	   "Serial #\t: %8phC\n"
 	   "Register Status\t:\n"
 	   "   Ctrl A\t: UIP  DV2  DV1  DV0  RS3  RS2  RS1  RS0\n"
 	   "\t\t:  %s\n"
···
 	   "   Ctrl 4B\t: ABE  E32k  CS  RCE  PRS  RIE  WIE  KSE\n"
 	   "\t\t:  %s\n",
 #else
-	   "Serial #\t: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
+	   "Serial #\t: %8phC\n",
 #endif
 	   model,
 	   ((ctrla & RTC_CTRL_A_DV1) ? "enabled" : "disabled"),
···
 	   (!((ctrl4b & RTC_CTRL_4B_E32K)) ?
 	    ds1685_rtc_sqw_freq[(ctrla & RTC_CTRL_A_RS_MASK)] : "32768Hz"),
 #ifdef CONFIG_RTC_DS1685_PROC_REGS
-	   ssn[0], ssn[1], ssn[2], ssn[3], ssn[4], ssn[5], ssn[6], ssn[7],
+	   ssn,
 	   ds1685_rtc_print_regs(ctrla, bits[0]),
 	   ds1685_rtc_print_regs(ctrlb, bits[1]),
 	   ds1685_rtc_print_regs(ctrlc, bits[2]),
···
 	   ds1685_rtc_print_regs(ctrl4a, bits[4]),
 	   ds1685_rtc_print_regs(ctrl4b, bits[5]));
 #else
-	   ssn[0], ssn[1], ssn[2], ssn[3], ssn[4], ssn[5], ssn[6], ssn[7]);
+	   ssn);
 #endif
 	return 0;
 }
···
 
 	ctrld = rtc->read(rtc, RTC_CTRL_D);
 
-	return snprintf(buf, 13, "%s\n",
+	return sprintf(buf, "%s\n",
 			(ctrld & RTC_CTRL_D_VRT) ? "ok" : "not ok or N/A");
 }
 static DEVICE_ATTR(battery, S_IRUGO, ds1685_rtc_sysfs_battery_show, NULL);
···
 	ctrl4a = rtc->read(rtc, RTC_EXT_CTRL_4A);
 	ds1685_rtc_switch_to_bank0(rtc);
 
-	return snprintf(buf, 13, "%s\n",
+	return sprintf(buf, "%s\n",
 			(ctrl4a & RTC_CTRL_4A_VRT2) ? "ok" : "not ok or N/A");
 }
 static DEVICE_ATTR(auxbatt, S_IRUGO, ds1685_rtc_sysfs_auxbatt_show, NULL);
···
 	ds1685_rtc_get_ssn(rtc, ssn);
 	ds1685_rtc_switch_to_bank0(rtc);
 
-	return snprintf(buf, 24, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
-			ssn[0], ssn[1], ssn[2], ssn[3], ssn[4], ssn[5],
-			ssn[6], ssn[7]);
-
-	return 0;
+	return sprintf(buf, "%8phC\n", ssn);
 }
 static DEVICE_ATTR(serial, S_IRUGO, ds1685_rtc_sysfs_serial_show, NULL);
 
···
 	tmp = rtc->read(rtc, reg_info->reg) & reg_info->bit;
 	ds1685_rtc_switch_to_bank0(rtc);
 
-	return snprintf(buf, 2, "%d\n", (tmp ? 1 : 0));
+	return sprintf(buf, "%d\n", (tmp ? 1 : 0));
 }
 
 /**
···
 	tmp = ds1685_rtc_bcd2bin(rtc, tmp, bcd_reg_info->mask,
 				 bin_reg_info->mask);
 
-	return snprintf(buf, 4, "%d\n", tmp);
+	return sprintf(buf, "%d\n", tmp);
 }
 
 /**

drivers/rtc/rtc-ds2404.c

···
 
 struct ds2404 {
 	struct ds2404_gpio *gpio;
-	struct ds2404_chip_ops *ops;
+	const struct ds2404_chip_ops *ops;
 	struct rtc_device *rtc;
 };
 
···
 		gpio_free(ds2404_gpio[i].gpio);
 }
 
-static struct ds2404_chip_ops ds2404_gpio_ops = {
+static const struct ds2404_chip_ops ds2404_gpio_ops = {
 	.map_io		= ds2404_gpio_map,
 	.unmap_io	= ds2404_gpio_unmap,
 };

drivers/rtc/rtc-efi.c

···
 	return status == EFI_SUCCESS ? 0 : -EINVAL;
 }
 
+static int efi_procfs(struct device *dev, struct seq_file *seq)
+{
+	efi_time_t      eft, alm;
+	efi_time_cap_t  cap;
+	efi_bool_t      enabled, pending;
+
+	memset(&eft, 0, sizeof(eft));
+	memset(&alm, 0, sizeof(alm));
+	memset(&cap, 0, sizeof(cap));
+
+	efi.get_time(&eft, &cap);
+	efi.get_wakeup_time(&enabled, &pending, &alm);
+
+	seq_printf(seq,
+		   "Time\t\t: %u:%u:%u.%09u\n"
+		   "Date\t\t: %u-%u-%u\n"
+		   "Daylight\t: %u\n",
+		   eft.hour, eft.minute, eft.second, eft.nanosecond,
+		   eft.year, eft.month, eft.day,
+		   eft.daylight);
+
+	if (eft.timezone == EFI_UNSPECIFIED_TIMEZONE)
+		seq_puts(seq, "Timezone\t: unspecified\n");
+	else
+		/* XXX fixme: convert to string? */
+		seq_printf(seq, "Timezone\t: %u\n", eft.timezone);
+
+	seq_printf(seq,
+		   "Alarm Time\t: %u:%u:%u.%09u\n"
+		   "Alarm Date\t: %u-%u-%u\n"
+		   "Alarm Daylight\t: %u\n"
+		   "Enabled\t\t: %s\n"
+		   "Pending\t\t: %s\n",
+		   alm.hour, alm.minute, alm.second, alm.nanosecond,
+		   alm.year, alm.month, alm.day,
+		   alm.daylight,
+		   enabled == 1 ? "yes" : "no",
+		   pending == 1 ? "yes" : "no");
+
+	if (eft.timezone == EFI_UNSPECIFIED_TIMEZONE)
+		seq_puts(seq, "Timezone\t: unspecified\n");
+	else
+		/* XXX fixme: convert to string? */
+		seq_printf(seq, "Timezone\t: %u\n", alm.timezone);
+
+	/*
+	 * now prints the capabilities
+	 */
+	seq_printf(seq,
+		   "Resolution\t: %u\n"
+		   "Accuracy\t: %u\n"
+		   "SetstoZero\t: %u\n",
+		   cap.resolution, cap.accuracy, cap.sets_to_zero);
+
+	return 0;
+}
+
 static const struct rtc_class_ops efi_rtc_ops = {
-	.read_time = efi_read_time,
-	.set_time = efi_set_time,
-	.read_alarm = efi_read_alarm,
-	.set_alarm = efi_set_alarm,
+	.read_time	= efi_read_time,
+	.set_time	= efi_set_time,
+	.read_alarm	= efi_read_alarm,
+	.set_alarm	= efi_set_alarm,
+	.proc		= efi_procfs,
 };
 
 static int __init efi_rtc_probe(struct platform_device *dev)

drivers/rtc/rtc-gemini.c

···
 	struct gemini_rtc *rtc = platform_get_drvdata(pdev);
 
 	rtc_device_unregister(rtc->rtc_dev);
-	platform_set_drvdata(pdev, NULL);
 
 	return 0;
 }

drivers/rtc/rtc-imxdi.c

···
 	sec = readl(imxdi->ioaddr + DTCMR);
 	if (sec != 0)
 		dev_warn(&imxdi->pdev->dev,
-			 "The security violation has happend at %u seconds\n",
+			 "The security violation has happened at %u seconds\n",
 			 sec);
 	/*
 	 * the timer cannot be set/modified if

drivers/rtc/rtc-lpc32xx.c

···
 	u32 tmp;
 
 	rtcirq = platform_get_irq(pdev, 0);
-	if (rtcirq < 0 || rtcirq >= NR_IRQS) {
+	if (rtcirq < 0) {
 		dev_warn(&pdev->dev, "Can't get interrupt resource\n");
 		rtcirq = -1;
 	}

drivers/rtc/rtc-pcf8523.c

···
 	u8 regs[8];
 	int err;
 
+	/*
+	 * The hardware can only store values between 0 and 99 in it's YEAR
+	 * register (with 99 overflowing to 0 on increment).
+	 * After 2100-02-28 we could start interpreting the year to be in the
+	 * interval [2100, 2199], but there is no path to switch in a smooth way
+	 * because the chip handles YEAR=0x00 (and the out-of-spec
+	 * YEAR=0xa0) as a leap year, but 2100 isn't.
+	 */
+	if (tm->tm_year < 100 || tm->tm_year >= 200)
+		return -EINVAL;
+
 	err = pcf8523_stop_rtc(client);
 	if (err < 0)
 		return err;

drivers/rtc/rtc-proc.c

···
 	int ret;
 	struct rtc_device *rtc = PDE_DATA(inode);
 
-	if (!try_module_get(THIS_MODULE))
+	if (!try_module_get(rtc->owner))
 		return -ENODEV;
 
 	ret = single_open(file, rtc_proc_show, rtc);
 	if (ret)
-		module_put(THIS_MODULE);
+		module_put(rtc->owner);
 	return ret;
 }
 
 static int rtc_proc_release(struct inode *inode, struct file *file)
 {
 	int res = single_release(inode, file);
-	module_put(THIS_MODULE);
+	struct rtc_device *rtc = PDE_DATA(inode);
+
+	module_put(rtc->owner);
 	return res;
 }
 

drivers/rtc/rtc-rv8803.c

···
 	struct i2c_client *client = dev_id;
 	struct rv8803_data *rv8803 = i2c_get_clientdata(client);
 	unsigned long events = 0;
-	u8 flags;
+	int flags;
 
 	spin_lock(&rv8803->flags_lock);
 
···
 
 static const struct i2c_device_id rv8803_id[] = {
 	{ "rv8803", 0 },
+	{ "rx8900", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, rv8803_id);

drivers/rtc/rtc-rx8010.c

···
+/*
+ * Driver for the Epson RTC module RX-8010 SJ
+ *
+ * Copyright(C) Timesys Corporation 2015
+ * Copyright(C) General Electric Company 2015
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/bcd.h>
+#include <linux/bitops.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtc.h>
+
+#define RX8010_SEC     0x10
+#define RX8010_MIN     0x11
+#define RX8010_HOUR    0x12
+#define RX8010_WDAY    0x13
+#define RX8010_MDAY    0x14
+#define RX8010_MONTH   0x15
+#define RX8010_YEAR    0x16
+#define RX8010_YEAR    0x16
+#define RX8010_RESV17  0x17
+#define RX8010_ALMIN   0x18
+#define RX8010_ALHOUR  0x19
+#define RX8010_ALWDAY  0x1A
+#define RX8010_TCOUNT0 0x1B
+#define RX8010_TCOUNT1 0x1C
+#define RX8010_EXT     0x1D
+#define RX8010_FLAG    0x1E
+#define RX8010_CTRL    0x1F
+/* 0x20 to 0x2F are user registers */
+#define RX8010_RESV30  0x30
+#define RX8010_RESV31  0x32
+#define RX8010_IRQ     0x32
+
+#define RX8010_EXT_WADA  BIT(3)
+
+#define RX8010_FLAG_VLF  BIT(1)
+#define RX8010_FLAG_AF   BIT(3)
+#define RX8010_FLAG_TF   BIT(4)
+#define RX8010_FLAG_UF   BIT(5)
+
+#define RX8010_CTRL_AIE  BIT(3)
+#define RX8010_CTRL_UIE  BIT(5)
+#define RX8010_CTRL_STOP BIT(6)
+#define RX8010_CTRL_TEST BIT(7)
+
+#define RX8010_ALARM_AE  BIT(7)
+
+static const struct i2c_device_id rx8010_id[] = {
+	{ "rx8010", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, rx8010_id);
+
+struct rx8010_data {
+	struct i2c_client *client;
+	struct rtc_device *rtc;
+	u8 ctrlreg;
+	spinlock_t flags_lock;
+};
+
+static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
+{
+	struct i2c_client *client = dev_id;
+	struct rx8010_data *rx8010 = i2c_get_clientdata(client);
+	int flagreg;
+
+	spin_lock(&rx8010->flags_lock);
+
+	flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
+
+	if (flagreg <= 0) {
+		spin_unlock(&rx8010->flags_lock);
+		return IRQ_NONE;
+	}
+
+	if (flagreg & RX8010_FLAG_VLF)
+		dev_warn(&client->dev, "Frequency stop detected\n");
+
+	if (flagreg & RX8010_FLAG_TF) {
+		flagreg &= ~RX8010_FLAG_TF;
+		rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF);
+	}
+
+	if (flagreg & RX8010_FLAG_AF) {
+		flagreg &= ~RX8010_FLAG_AF;
+		rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF);
+	}
+
+	if (flagreg & RX8010_FLAG_UF) {
+		flagreg &= ~RX8010_FLAG_UF;
+		rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);
+	}
+
+	i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
+
+	spin_unlock(&rx8010->flags_lock);
+	return IRQ_HANDLED;
+}
+
+static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
+{
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	u8 date[7];
+	int flagreg;
+	int err;
+
+	flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
+	if (flagreg < 0)
+		return flagreg;
+
+	if (flagreg & RX8010_FLAG_VLF) {
+		dev_warn(dev, "Frequency stop detected\n");
+		return -EINVAL;
+	}
+
+	err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC,
+					    7, date);
+	if (err != 7)
+		return err < 0 ? err : -EIO;
+
+	dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
+	dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
+	dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);
+	dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);
+	dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1;
+	dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100;
+	dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f);
+
+	return rtc_valid_tm(dt);
+}
+
+static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
+{
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	u8 date[7];
+	int ctrl, flagreg;
+	int ret;
+	unsigned long irqflags;
+
+	if ((dt->tm_year < 100) || (dt->tm_year > 199))
+		return -EINVAL;
+
+	/* set STOP bit before changing clock/calendar */
+	ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
+	if (ctrl < 0)
+		return ctrl;
+	rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP;
+	ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
+					rx8010->ctrlreg);
+	if (ret < 0)
+		return ret;
+
+	date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);
+	date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min);
+	date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour);
+	date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday);
+	date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1);
+	date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);
+	date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday);
+
+	ret = i2c_smbus_write_i2c_block_data(rx8010->client,
+					     RX8010_SEC, 7, date);
+	if (ret < 0)
+		return ret;
+
+	/* clear STOP bit after changing clock/calendar */
+	ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
+	if (ctrl < 0)
+		return ctrl;
+	rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP;
+	ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
+					rx8010->ctrlreg);
+	if (ret < 0)
+		return ret;
+
+	spin_lock_irqsave(&rx8010->flags_lock, irqflags);
+
+	flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
+	if (flagreg < 0) {
+		spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+		return flagreg;
+	}
+
+	if (flagreg & RX8010_FLAG_VLF)
+		ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG,
+						flagreg & ~RX8010_FLAG_VLF);
+
+	spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+
+	return 0;
+}
+
+static int rx8010_init_client(struct i2c_client *client)
+{
+	struct rx8010_data *rx8010 = i2c_get_clientdata(client);
+	u8 ctrl[2];
+	int need_clear = 0, err = 0;
+
+	/* Initialize reserved registers as specified in datasheet */
+	err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8);
+	if (err < 0)
+		return err;
+
+	err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00);
+	if (err < 0)
+		return err;
+
+	err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08);
+	if (err < 0)
+		return err;
+
+	err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00);
+	if (err < 0)
+		return err;
+
+	err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG,
+					    2, ctrl);
+	if (err != 2)
+		return err < 0 ? err : -EIO;
+
+	if (ctrl[0] & RX8010_FLAG_VLF)
+		dev_warn(&client->dev, "Frequency stop was detected\n");
+
+	if (ctrl[0] & RX8010_FLAG_AF) {
+		dev_warn(&client->dev, "Alarm was detected\n");
+		need_clear = 1;
+	}
+
+	if (ctrl[0] & RX8010_FLAG_TF)
+		need_clear = 1;
+
+	if (ctrl[0] & RX8010_FLAG_UF)
+		need_clear = 1;
+
+	if (need_clear) {
+		ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);
+		err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]);
+		if (err < 0)
+			return err;
+	}
+
+	rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST);
+
+	return err;
+}
+
+static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	struct i2c_client *client = rx8010->client;
+	u8 alarmvals[3];
+	int flagreg;
+	int err;
+
+	err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals);
+	if (err != 3)
+		return err < 0 ? err : -EIO;
+
+	flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
+	if (flagreg < 0)
+		return flagreg;
+
+	t->time.tm_sec = 0;
+	t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
+	t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
+
+	if (alarmvals[2] & RX8010_ALARM_AE)
+		t->time.tm_mday = -1;
+	else
+		t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f);
+
+	t->time.tm_wday = -1;
+	t->time.tm_mon = -1;
+	t->time.tm_year = -1;
+
+	t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE);
+	t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled;
+
+	return err;
+}
+
+static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	u8 alarmvals[3];
+	int extreg, flagreg;
+	int err;
+	unsigned long irqflags;
+
+	spin_lock_irqsave(&rx8010->flags_lock, irqflags);
+	flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
+	if (flagreg < 0) {
+		spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+		return flagreg;
+	}
+
+	if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) {
+		rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE);
+		err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
+						rx8010->ctrlreg);
+		if (err < 0) {
+			spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+			return err;
+		}
+	}
+
+	flagreg &= ~RX8010_FLAG_AF;
+	err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
+	spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+	if (err < 0)
+		return err;
+
+	alarmvals[0] = bin2bcd(t->time.tm_min);
+	alarmvals[1] = bin2bcd(t->time.tm_hour);
+	alarmvals[2] = bin2bcd(t->time.tm_mday);
+
+	err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN,
+					     2, alarmvals);
+	if (err < 0)
+		return err;
+
+	extreg = i2c_smbus_read_byte_data(client, RX8010_EXT);
+	if (extreg < 0)
+		return extreg;
+
+	extreg |= RX8010_EXT_WADA;
+	err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg);
+	if (err < 0)
+		return err;
+
+	if (alarmvals[2] == 0)
+		alarmvals[2] |= RX8010_ALARM_AE;
+
+	err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY,
+					alarmvals[2]);
+	if (err < 0)
+		return err;
+
+	if (t->enabled) {
+		if (rx8010->rtc->uie_rtctimer.enabled)
+			rx8010->ctrlreg |= RX8010_CTRL_UIE;
+		if (rx8010->rtc->aie_timer.enabled)
+			rx8010->ctrlreg |=
+				(RX8010_CTRL_AIE | RX8010_CTRL_UIE);
+
+		err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
+						rx8010->ctrlreg);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
+static int rx8010_alarm_irq_enable(struct device *dev,
+				   unsigned int enabled)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	int flagreg;
+	u8 ctrl;
+	int err;
+
+	ctrl = rx8010->ctrlreg;
+
+	if (enabled) {
+		if (rx8010->rtc->uie_rtctimer.enabled)
+			ctrl |= RX8010_CTRL_UIE;
+		if (rx8010->rtc->aie_timer.enabled)
+			ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE);
+	} else {
+		if (!rx8010->rtc->uie_rtctimer.enabled)
+			ctrl &= ~RX8010_CTRL_UIE;
+		if (!rx8010->rtc->aie_timer.enabled)
+			ctrl &= ~RX8010_CTRL_AIE;
+	}
+
+	flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
+	if (flagreg < 0)
+		return flagreg;
+
+	flagreg &= ~RX8010_FLAG_AF;
+	err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
+	if (err < 0)
+		return err;
+
+	if (ctrl != rx8010->ctrlreg) {
+		rx8010->ctrlreg = ctrl;
+		err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
+						rx8010->ctrlreg);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
+static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
+	int ret, tmp;
+	int flagreg;
+	unsigned long irqflags;
+
+	switch (cmd) {
+	case RTC_VL_READ:
+		flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
+		if (flagreg < 0)
+			return flagreg;
+
+		tmp = !!(flagreg & RX8010_FLAG_VLF);
+		if (copy_to_user((void __user *)arg, &tmp, sizeof(int)))
+			return -EFAULT;
+
+		return 0;
+
+	case RTC_VL_CLR:
+		spin_lock_irqsave(&rx8010->flags_lock, irqflags);
+		flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
+		if (flagreg < 0) {
+			spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+			return flagreg;
+		}
+
+		flagreg &= ~RX8010_FLAG_VLF;
+		ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
+		spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
+		if (ret < 0)
+			return ret;
+
+		return 0;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+static struct rtc_class_ops rx8010_rtc_ops = {
+	.read_time = rx8010_get_time,
+	.set_time = rx8010_set_time,
+	.ioctl = rx8010_ioctl,
+};
+
+static int rx8010_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	struct rx8010_data *rx8010;
+	int err = 0;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
+		| I2C_FUNC_SMBUS_I2C_BLOCK)) {
+		dev_err(&adapter->dev, "doesn't support required functionality\n");
+		return -EIO;
+	}
+
+	rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data),
+			      GFP_KERNEL);
+	if (!rx8010)
+		return -ENOMEM;
+
+	rx8010->client = client;
+	i2c_set_clientdata(client, rx8010);
+
+	spin_lock_init(&rx8010->flags_lock);
+
+	err = rx8010_init_client(client);
+	if (err)
+		return err;
+
+	if (client->irq > 0) {
+		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
+		err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
+						rx8010_irq_1_handler,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						"rx8010", client);
+
+		if (err) {
+			dev_err(&client->dev, "unable to request IRQ\n");
+			client->irq = 0;
+		} else {
+			rx8010_rtc_ops.read_alarm = rx8010_read_alarm;
+			rx8010_rtc_ops.set_alarm = rx8010_set_alarm;
+			rx8010_rtc_ops.alarm_irq_enable = rx8010_alarm_irq_enable;
+		}
+	}
+
+	rx8010->rtc = devm_rtc_device_register(&client->dev, client->name,
+		&rx8010_rtc_ops, THIS_MODULE);
+
+	if (IS_ERR(rx8010->rtc)) {
+		dev_err(&client->dev, "unable to register the class device\n");
+		return PTR_ERR(rx8010->rtc);
+	}
+
+	rx8010->rtc->max_user_freq = 1;
+
+	return err;
+}
+
+static struct i2c_driver rx8010_driver = {
+	.driver = {
+		.name = "rtc-rx8010",
+	},
+	.probe		= rx8010_probe,
+	.id_table	= rx8010_id,
+};
+
+module_i2c_driver(rx8010_driver);
+
+MODULE_AUTHOR("Akshay Bhat <[e-mail]>");
+MODULE_DESCRIPTION("Epson RX8010SJ RTC driver");
+MODULE_LICENSE("GPL v2");

drivers/rtc/rtc-s5m.c

···
  */
 #define UDR_READ_RETRY_CNT	5
 
-/* Registers used by the driver which are different between chipsets. */
+/*
+ * Registers used by the driver which are different between chipsets.
+ *
+ * Operations like read time and write alarm/time require updating
+ * specific fields in UDR register. These fields usually are auto-cleared
+ * (with some exceptions).
+ *
+ * Table of operations per device:
+ *
+ * Device     | Write time | Read time | Write alarm
+ * =================================================
+ * S5M8767    | UDR + TIME |           | UDR
+ * S2MPS11/14 | WUDR       | RUDR      | WUDR + RUDR
+ * S2MPS13    | WUDR       | RUDR      | WUDR + AUDR
+ * S2MPS15    | WUDR       | RUDR      | AUDR
+ */
 struct s5m_rtc_reg_config {
 	/* Number of registers used for setting time/alarm0/alarm1 */
 	unsigned int regs_count;
···
 	 * will enable update of time or alarm register. Then it will be
 	 * auto-cleared after successful update.
 	 */
-	unsigned int rtc_udr_update;
-	/* Mask for UDR field in 'rtc_udr_update' register */
-	unsigned int rtc_udr_mask;
+	unsigned int udr_update;
+	/* Auto-cleared mask in UDR field for writing time and alarm */
+	unsigned int autoclear_udr_mask;
+	/*
+	 * Masks in UDR field for time and alarm operations.
+	 * The read time mask can be 0. Rest should not.
+	 */
+	unsigned int read_time_udr_mask;
+	unsigned int write_time_udr_mask;
+	unsigned int write_alarm_udr_mask;
 };
 
 /* Register map for S5M8763 and S5M8767 */
···
 	.ctrl			= S5M_ALARM1_CONF,
 	.alarm0			= S5M_ALARM0_SEC,
 	.alarm1			= S5M_ALARM1_SEC,
-	.rtc_udr_update		= S5M_RTC_UDR_CON,
-	.rtc_udr_mask		= S5M_RTC_UDR_MASK,
+	.udr_update		= S5M_RTC_UDR_CON,
+	.autoclear_udr_mask	= S5M_RTC_UDR_MASK,
+	.read_time_udr_mask	= 0, /* Not needed */
+	.write_time_udr_mask	= S5M_RTC_UDR_MASK | S5M_RTC_TIME_EN_MASK,
+	.write_alarm_udr_mask	= S5M_RTC_UDR_MASK,
 };
 
-/*
- * Register map for S2MPS14.
- * It may be also suitable for S2MPS11 but this was not tested.
- */
-static const struct s5m_rtc_reg_config s2mps_rtc_regs = {
+/* Register map for S2MPS13 */
+static const struct s5m_rtc_reg_config s2mps13_rtc_regs = {
 	.regs_count		= 7,
 	.time			= S2MPS_RTC_SEC,
 	.ctrl			= S2MPS_RTC_CTRL,
 	.alarm0			= S2MPS_ALARM0_SEC,
 	.alarm1			= S2MPS_ALARM1_SEC,
-	.rtc_udr_update		= S2MPS_RTC_UDR_CON,
-	.rtc_udr_mask		= S2MPS_RTC_WUDR_MASK,
+	.udr_update		= S2MPS_RTC_UDR_CON,
+	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
+	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
+	.write_time_udr_mask	= S2MPS_RTC_WUDR_MASK,
+	.write_alarm_udr_mask	= S2MPS_RTC_WUDR_MASK | S2MPS13_RTC_AUDR_MASK,
+};
+
+/* Register map for S2MPS11/14 */
+static const struct s5m_rtc_reg_config s2mps14_rtc_regs = {
+	.regs_count		= 7,
+	.time			= S2MPS_RTC_SEC,
+	.ctrl			= S2MPS_RTC_CTRL,
+	.alarm0			= S2MPS_ALARM0_SEC,
+	.alarm1			= S2MPS_ALARM1_SEC,
+	.udr_update		= S2MPS_RTC_UDR_CON,
+	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
+	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
+	.write_time_udr_mask	= S2MPS_RTC_WUDR_MASK,
+	.write_alarm_udr_mask	= S2MPS_RTC_WUDR_MASK | S2MPS_RTC_RUDR_MASK,
+};
+
+/*
+ * Register map for S2MPS15 - in comparison to S2MPS14 the WUDR and AUDR bits
+ * are swapped.
+ */
+static const struct s5m_rtc_reg_config s2mps15_rtc_regs = {
+	.regs_count		= 7,
+	.time			= S2MPS_RTC_SEC,
+	.ctrl			= S2MPS_RTC_CTRL,
+	.alarm0			= S2MPS_ALARM0_SEC,
+	.alarm1			= S2MPS_ALARM1_SEC,
+	.udr_update		= S2MPS_RTC_UDR_CON,
+	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
+	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
+	.write_time_udr_mask	= S2MPS15_RTC_WUDR_MASK,
+	.write_alarm_udr_mask	= S2MPS15_RTC_AUDR_MASK,
 };
 
 struct s5m_rtc_info {
···
 	unsigned int data;
 
 	do {
-		ret = regmap_read(info->regmap, info->regs->rtc_udr_update,
-				&data);
-	} while (--retry && (data & info->regs->rtc_udr_mask) && !ret);
+		ret = regmap_read(info->regmap, info->regs->udr_update, &data);
+	} while (--retry && (data & info->regs->autoclear_udr_mask) && !ret);
 
 	if (!retry)
 		dev_err(info->dev, "waiting for UDR update, reached max number of retries\n");
···
 	int ret;
 	unsigned int data;
 
-	ret = regmap_read(info->regmap, info->regs->rtc_udr_update, &data);
+	ret = regmap_read(info->regmap, info->regs->udr_update, &data);
 	if (ret < 0) {
 		dev_err(info->dev, "failed to read update reg(%d)\n", ret);
 		return ret;
 	}
 
-	switch (info->device_type) {
-	case S5M8763X:
-	case S5M8767X:
-		data |= info->regs->rtc_udr_mask | S5M_RTC_TIME_EN_MASK;
-	case S2MPS15X:
-		/* As per UM, for write time register, set WUDR bit to high */
-		data |= S2MPS15_RTC_WUDR_MASK;
-		break;
-	case S2MPS14X:
-	case S2MPS13X:
-		data |= info->regs->rtc_udr_mask;
-		break;
-	default:
-		return -EINVAL;
-	}
+	data |= info->regs->write_time_udr_mask;
 
-
-	ret = regmap_write(info->regmap, info->regs->rtc_udr_update, data);
+	ret = regmap_write(info->regmap, info->regs->udr_update, data);
 	if (ret < 0) {
 		dev_err(info->dev, "failed to write update reg(%d)\n", ret);
 		return ret;
···
 	int ret;
 	unsigned int data;
 
-	ret = regmap_read(info->regmap, info->regs->rtc_udr_update, &data);
+	ret = regmap_read(info->regmap, info->regs->udr_update, &data);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to read update reg(%d)\n",
 			__func__, ret);
 		return ret;
 	}
 
-	data |= info->regs->rtc_udr_mask;
+	data |= info->regs->write_alarm_udr_mask;
 	switch (info->device_type) {
 	case S5M8763X:
 	case S5M8767X:
 		data &= ~S5M_RTC_TIME_EN_MASK;
 		break;
 	case S2MPS15X:
-		/* As per UM, for write alarm, set A_UDR(bit[4]) to high
-		 * rtc_udr_mask above sets bit[4]
-		 */
-		break;
 	case S2MPS14X:
-		data |= S2MPS_RTC_RUDR_MASK;
-		break;
 	case S2MPS13X:
-		data |= S2MPS13_RTC_AUDR_MASK;
+		/* No exceptions needed */
 		break;
 	default:
 		return -EINVAL;
 	}
 
-	ret = regmap_write(info->regmap, info->regs->rtc_udr_update, data);
+	ret = regmap_write(info->regmap, info->regs->udr_update, data);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write update reg(%d)\n",
 			__func__, ret);
···
 
 	/* On S2MPS13 the AUDR is not auto-cleared */
 	if (info->device_type == S2MPS13X)
-		regmap_update_bits(info->regmap, info->regs->rtc_udr_update,
+		regmap_update_bits(info->regmap, info->regs->udr_update,
 				   S2MPS13_RTC_AUDR_MASK, 0);
 
 	return ret;
···
 	u8 data[info->regs->regs_count];
 	int ret;
 
-	if (info->device_type == S2MPS15X || info->device_type == S2MPS14X ||
-			info->device_type == S2MPS13X) {
+	if (info->regs->read_time_udr_mask) {
 		ret = regmap_update_bits(info->regmap,
-				info->regs->rtc_udr_update,
-				S2MPS_RTC_RUDR_MASK, S2MPS_RTC_RUDR_MASK);
+				info->regs->udr_update,
+				info->regs->read_time_udr_mask,
+				info->regs->read_time_udr_mask);
 		if (ret) {
 			dev_err(dev,
 				"Failed to prepare registers for time reading: %d\n",
···
 
 	switch (platform_get_device_id(pdev)->driver_data) {
 	case S2MPS15X:
+		regmap_cfg = &s2mps14_rtc_regmap_config;
+		info->regs = &s2mps15_rtc_regs;
+		alarm_irq = S2MPS14_IRQ_RTCA0;
+		break;
 	case S2MPS14X:
+		regmap_cfg = &s2mps14_rtc_regmap_config;
+		info->regs = &s2mps14_rtc_regs;
+		alarm_irq = S2MPS14_IRQ_RTCA0;
+		break;
 	case S2MPS13X:
 		regmap_cfg = &s2mps14_rtc_regmap_config;
-		info->regs = &s2mps_rtc_regs;
+		info->regs = &s2mps13_rtc_regs;
 		alarm_irq = S2MPS14_IRQ_RTCA0;
 		break;
 	case S5M8763X:

drivers/rtc/rtc-sunxi.c

···
 	unsigned char leap_shift;	/* bit shift to get the leap year */
 };
 
-static struct sunxi_rtc_data_year data_year_param[] = {
+static const struct sunxi_rtc_data_year data_year_param[] = {
 	[0] = {
 		.min		= 2010,
 		.max		= 2073,
···
 struct sunxi_rtc_dev {
 	struct rtc_device *rtc;
 	struct device *dev;
-	struct sunxi_rtc_data_year *data_year;
+	const struct sunxi_rtc_data_year *data_year;
 	void __iomem *base;
 	int irq;
 };
···
 	return IRQ_NONE;
 }
 
-static void sunxi_rtc_setaie(int to, struct sunxi_rtc_dev *chip)
+static void sunxi_rtc_setaie(unsigned int to, struct sunxi_rtc_dev *chip)
 {
 	u32 alrm_val = 0;
 	u32 alrm_irq_val = 0;
···
 	struct sunxi_rtc_dev *chip = dev_get_drvdata(dev);
 	u32 date = 0;
 	u32 time = 0;
-	int year;
+	unsigned int year;
 
 	/*
 	 * the input rtc_tm->tm_year is the offset relative to 1900. We use
···
 
 	year = rtc_tm->tm_year + 1900;
 	if (year < chip->data_year->min || year > chip->data_year->max) {
-		dev_err(dev, "rtc only supports year in range %d - %d\n",
-				chip->data_year->min, chip->data_year->max);
+		dev_err(dev, "rtc only supports year in range %u - %u\n",
+			chip->data_year->min, chip->data_year->max);
 		return -EINVAL;
 	}
 
···
 {
 	struct sunxi_rtc_dev *chip;
 	struct resource *res;
-	const struct of_device_id *of_id;
 	int ret;
 
 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
···
 		return ret;
 	}
 
-	of_id = of_match_device(sunxi_rtc_dt_ids, &pdev->dev);
-	if (!of_id) {
+	chip->data_year = of_device_get_match_data(&pdev->dev);
+	if (!chip->data_year) {
 		dev_err(&pdev->dev, "Unable to setup RTC data\n");
 		return -ENODEV;
 	}
-	chip->data_year = (struct sunxi_rtc_data_year *) of_id->data;
 
 	/* clear the alarm count value */
 	writel(0, chip->base + SUNXI_ALRM_DHMS);

drivers/rtc/rtc-sysfs.c

···
 		const char *buf, size_t n)
 {
 	struct rtc_device *rtc = to_rtc_device(dev);
-	unsigned long val = simple_strtoul(buf, NULL, 0);
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 0, &val);
+	if (err)
+		return err;
 
 	if (val >= 4096 || val == 0)
 		return -EINVAL;
···
 		} else
 			adjust = 1;
 	}
-	alarm = simple_strtoul(buf_ptr, NULL, 0);
+	retval = kstrtoul(buf_ptr, 0, &alarm);
+	if (retval)
+		return retval;
 	if (adjust) {
 		alarm += now;
 	}

drivers/rtc/rtc-v3020.c

···
 	/* GPIO access */
 	struct gpio *gpio;
 
-	struct v3020_chip_ops *ops;
+	const struct v3020_chip_ops *ops;
 
 	struct rtc_device *rtc;
 };
···
 	return !!(readl(chip->ioaddress) & (1 << chip->leftshift));
 }
 
-static struct v3020_chip_ops v3020_mmio_ops = {
+static const struct v3020_chip_ops v3020_mmio_ops = {
 	.map_io		= v3020_mmio_map,
 	.unmap_io	= v3020_mmio_unmap,
 	.read_bit	= v3020_mmio_read_bit,
···
 	return bit;
 }
 
-static struct v3020_chip_ops v3020_gpio_ops = {
+static const struct v3020_chip_ops v3020_gpio_ops = {
 	.map_io		= v3020_gpio_map,
 	.unmap_io	= v3020_gpio_unmap,
 	.read_bit	= v3020_gpio_read_bit,

include/linux/mfd/samsung/rtc.h

···
 #define S5M_RTC_UDR_MASK	(1 << S5M_RTC_UDR_SHIFT)
 #define S2MPS_RTC_WUDR_SHIFT	4
 #define S2MPS_RTC_WUDR_MASK	(1 << S2MPS_RTC_WUDR_SHIFT)
+#define S2MPS15_RTC_AUDR_SHIFT	4
+#define S2MPS15_RTC_AUDR_MASK	(1 << S2MPS15_RTC_AUDR_SHIFT)
 #define S2MPS13_RTC_AUDR_SHIFT	1
 #define S2MPS13_RTC_AUDR_MASK	(1 << S2MPS13_RTC_AUDR_SHIFT)
 #define S2MPS15_RTC_WUDR_SHIFT	1