Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1001 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-rv3029c2.c b/drivers/rtc/rtc-rv3029c2.c
new file mode 100644
index 000000000..cfe3aece5
--- /dev/null
+++ b/drivers/rtc/rtc-rv3029c2.c
@@ -0,0 +1,1001 @@
+/*
+ * Micro Crystal RV-3029 / RV-3049 rtc class driver
+ *
+ * Author: Gregory Hermant <gregory.hermant@calao-systems.com>
+ *         Michael Buesch <m@bues.ch>
+ *
+ * based on previously existing rtc class drivers
+ *
+ * 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/module.h>
+#include <linux/i2c.h>
+#include <linux/spi/spi.h>
+#include <linux/bcd.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/regmap.h>
+
+/* Register map */
+/* control section */
+#define RV3029_ONOFF_CTRL		0x00
+#define RV3029_ONOFF_CTRL_WE		BIT(0)
+#define RV3029_ONOFF_CTRL_TE		BIT(1)
+#define RV3029_ONOFF_CTRL_TAR		BIT(2)
+#define RV3029_ONOFF_CTRL_EERE		BIT(3)
+#define RV3029_ONOFF_CTRL_SRON		BIT(4)
+#define RV3029_ONOFF_CTRL_TD0		BIT(5)
+#define RV3029_ONOFF_CTRL_TD1		BIT(6)
+#define RV3029_ONOFF_CTRL_CLKINT	BIT(7)
+#define RV3029_IRQ_CTRL			0x01
+#define RV3029_IRQ_CTRL_AIE		BIT(0)
+#define RV3029_IRQ_CTRL_TIE		BIT(1)
+#define RV3029_IRQ_CTRL_V1IE		BIT(2)
+#define RV3029_IRQ_CTRL_V2IE		BIT(3)
+#define RV3029_IRQ_CTRL_SRIE		BIT(4)
+#define RV3029_IRQ_FLAGS		0x02
+#define RV3029_IRQ_FLAGS_AF		BIT(0)
+#define RV3029_IRQ_FLAGS_TF		BIT(1)
+#define RV3029_IRQ_FLAGS_V1IF		BIT(2)
+#define RV3029_IRQ_FLAGS_V2IF		BIT(3)
+#define RV3029_IRQ_FLAGS_SRF		BIT(4)
+#define RV3029_STATUS			0x03
+#define RV3029_STATUS_VLOW1		BIT(2)
+#define RV3029_STATUS_VLOW2		BIT(3)
+#define RV3029_STATUS_SR		BIT(4)
+#define RV3029_STATUS_PON		BIT(5)
+#define RV3029_STATUS_EEBUSY		BIT(7)
+#define RV3029_RST_CTRL			0x04
+#define RV3029_RST_CTRL_SYSR		BIT(4)
+#define RV3029_CONTROL_SECTION_LEN	0x05
+
+/* watch section */
+#define RV3029_W_SEC			0x08
+#define RV3029_W_MINUTES		0x09
+#define RV3029_W_HOURS			0x0A
+#define RV3029_REG_HR_12_24		BIT(6) /* 24h/12h mode */
+#define RV3029_REG_HR_PM		BIT(5) /* PM/AM bit in 12h mode */
+#define RV3029_W_DATE			0x0B
+#define RV3029_W_DAYS			0x0C
+#define RV3029_W_MONTHS			0x0D
+#define RV3029_W_YEARS			0x0E
+#define RV3029_WATCH_SECTION_LEN	0x07
+
+/* alarm section */
+#define RV3029_A_SC			0x10
+#define RV3029_A_MN			0x11
+#define RV3029_A_HR			0x12
+#define RV3029_A_DT			0x13
+#define RV3029_A_DW			0x14
+#define RV3029_A_MO			0x15
+#define RV3029_A_YR			0x16
+#define RV3029_A_AE_X			BIT(7)
+#define RV3029_ALARM_SECTION_LEN	0x07
+
+/* timer section */
+#define RV3029_TIMER_LOW		0x18
+#define RV3029_TIMER_HIGH		0x19
+
+/* temperature section */
+#define RV3029_TEMP_PAGE		0x20
+
+/* eeprom data section */
+#define RV3029_E2P_EEDATA1		0x28
+#define RV3029_E2P_EEDATA2		0x29
+#define RV3029_E2PDATA_SECTION_LEN	0x02
+
+/* eeprom control section */
+#define RV3029_CONTROL_E2P_EECTRL	0x30
+#define RV3029_EECTRL_THP		BIT(0) /* temp scan interval */
+#define RV3029_EECTRL_THE		BIT(1) /* thermometer enable */
+#define RV3029_EECTRL_FD0		BIT(2) /* CLKOUT */
+#define RV3029_EECTRL_FD1		BIT(3) /* CLKOUT */
+#define RV3029_TRICKLE_1K		BIT(4) /* 1.5K resistance */
+#define RV3029_TRICKLE_5K		BIT(5) /* 5K   resistance */
+#define RV3029_TRICKLE_20K		BIT(6) /* 20K  resistance */
+#define RV3029_TRICKLE_80K		BIT(7) /* 80K  resistance */
+#define RV3029_TRICKLE_MASK		(RV3029_TRICKLE_1K |\
+					 RV3029_TRICKLE_5K |\
+					 RV3029_TRICKLE_20K |\
+					 RV3029_TRICKLE_80K)
+#define RV3029_TRICKLE_SHIFT		4
+#define RV3029_CONTROL_E2P_XOFFS	0x31 /* XTAL offset */
+#define RV3029_CONTROL_E2P_XOFFS_SIGN	BIT(7) /* Sign: 1->pos, 0->neg */
+#define RV3029_CONTROL_E2P_QCOEF	0x32 /* XTAL temp drift coef */
+#define RV3029_CONTROL_E2P_TURNOVER	0x33 /* XTAL turnover temp (in *C) */
+#define RV3029_CONTROL_E2P_TOV_MASK	0x3F /* XTAL turnover temp mask */
+
+/* user ram section */
+#define RV3029_USR1_RAM_PAGE		0x38
+#define RV3029_USR1_SECTION_LEN		0x04
+#define RV3029_USR2_RAM_PAGE		0x3C
+#define RV3029_USR2_SECTION_LEN		0x04
+
+struct rv3029_data {
+	struct device		*dev;
+	struct rtc_device	*rtc;
+	struct regmap		*regmap;
+	int irq;
+};
+
+static int rv3029_read_regs(struct device *dev, u8 reg, u8 *buf,
+			    unsigned int len)
+{
+	struct rv3029_data *rv3029 = dev_get_drvdata(dev);
+
+	if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
+	    (reg + len > RV3029_USR1_RAM_PAGE + 8))
+		return -EINVAL;
+
+	return regmap_bulk_read(rv3029->regmap, reg, buf, len);
+}
+
+static int rv3029_write_regs(struct device *dev, u8 reg, u8 const buf[],
+			     unsigned int len)
+{
+	struct rv3029_data *rv3029 = dev_get_drvdata(dev);
+
+	if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
+	    (reg + len > RV3029_USR1_RAM_PAGE + 8))
+		return -EINVAL;
+
+	return regmap_bulk_write(rv3029->regmap, reg, buf, len);
+}
+
+static int rv3029_update_bits(struct device *dev, u8 reg, u8 mask, u8 set)
+{
+	u8 buf;
+	int ret;
+
+	ret = rv3029_read_regs(dev, reg, &buf, 1);
+	if (ret < 0)
+		return ret;
+	buf &= ~mask;
+	buf |= set & mask;
+	ret = rv3029_write_regs(dev, reg, &buf, 1);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int rv3029_get_sr(struct device *dev, u8 *buf)
+{
+	int ret = rv3029_read_regs(dev, RV3029_STATUS, buf, 1);
+
+	if (ret < 0)
+		return -EIO;
+	dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
+	return 0;
+}
+
+static int rv3029_set_sr(struct device *dev, u8 val)
+{
+	u8 buf[1];
+	int sr;
+
+	buf[0] = val;
+	sr = rv3029_write_regs(dev, RV3029_STATUS, buf, 1);
+	dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
+	if (sr < 0)
+		return -EIO;
+	return 0;
+}
+
+static int rv3029_eeprom_busywait(struct device *dev)
+{
+	int i, ret;
+	u8 sr;
+
+	for (i = 100; i > 0; i--) {
+		ret = rv3029_get_sr(dev, &sr);
+		if (ret < 0)
+			break;
+		if (!(sr & RV3029_STATUS_EEBUSY))
+			break;
+		usleep_range(1000, 10000);
+	}
+	if (i <= 0) {
+		dev_err(dev, "EEPROM busy wait timeout.\n");
+		return -ETIMEDOUT;
+	}
+
+	return ret;
+}
+
+static int rv3029_eeprom_exit(struct device *dev)
+{
+	/* Re-enable eeprom refresh */
+	return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
+				  RV3029_ONOFF_CTRL_EERE,
+				  RV3029_ONOFF_CTRL_EERE);
+}
+
+static int rv3029_eeprom_enter(struct device *dev)
+{
+	int ret;
+	u8 sr;
+
+	/* Check whether we are in the allowed voltage range. */
+	ret = rv3029_get_sr(dev, &sr);
+	if (ret < 0)
+		return ret;
+	if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
+		/* We clear the bits and retry once just in case
+		 * we had a brown out in early startup.
+		 */
+		sr &= ~RV3029_STATUS_VLOW1;
+		sr &= ~RV3029_STATUS_VLOW2;
+		ret = rv3029_set_sr(dev, sr);
+		if (ret < 0)
+			return ret;
+		usleep_range(1000, 10000);
+		ret = rv3029_get_sr(dev, &sr);
+		if (ret < 0)
+			return ret;
+		if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
+			dev_err(dev,
+				"Supply voltage is too low to safely access the EEPROM.\n");
+			return -ENODEV;
+		}
+	}
+
+	/* Disable eeprom refresh. */
+	ret = rv3029_update_bits(dev, RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE,
+				 0);
+	if (ret < 0)
+		return ret;
+
+	/* Wait for any previous eeprom accesses to finish. */
+	ret = rv3029_eeprom_busywait(dev);
+	if (ret < 0)
+		rv3029_eeprom_exit(dev);
+
+	return ret;
+}
+
+static int rv3029_eeprom_read(struct device *dev, u8 reg,
+			      u8 buf[], size_t len)
+{
+	int ret, err;
+
+	err = rv3029_eeprom_enter(dev);
+	if (err < 0)
+		return err;
+
+	ret = rv3029_read_regs(dev, reg, buf, len);
+
+	err = rv3029_eeprom_exit(dev);
+	if (err < 0)
+		return err;
+
+	return ret;
+}
+
+static int rv3029_eeprom_write(struct device *dev, u8 reg,
+			       u8 const buf[], size_t len)
+{
+	int ret, err;
+	size_t i;
+	u8 tmp;
+
+	err = rv3029_eeprom_enter(dev);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < len; i++, reg++) {
+		ret = rv3029_read_regs(dev, reg, &tmp, 1);
+		if (ret < 0)
+			break;
+		if (tmp != buf[i]) {
+			ret = rv3029_write_regs(dev, reg, &buf[i], 1);
+			if (ret < 0)
+				break;
+		}
+		ret = rv3029_eeprom_busywait(dev);
+		if (ret < 0)
+			break;
+	}
+
+	err = rv3029_eeprom_exit(dev);
+	if (err < 0)
+		return err;
+
+	return ret;
+}
+
+static int rv3029_eeprom_update_bits(struct device *dev,
+				     u8 reg, u8 mask, u8 set)
+{
+	u8 buf;
+	int ret;
+
+	ret = rv3029_eeprom_read(dev, reg, &buf, 1);
+	if (ret < 0)
+		return ret;
+	buf &= ~mask;
+	buf |= set & mask;
+	ret = rv3029_eeprom_write(dev, reg, &buf, 1);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static irqreturn_t rv3029_handle_irq(int irq, void *dev_id)
+{
+	struct device *dev = dev_id;
+	struct rv3029_data *rv3029 = dev_get_drvdata(dev);
+	struct mutex *lock = &rv3029->rtc->ops_lock;
+	unsigned long events = 0;
+	u8 flags, controls;
+	int ret;
+
+	mutex_lock(lock);
+
+	ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
+	if (ret) {
+		dev_warn(dev, "Read IRQ Control Register error %d\n", ret);
+		mutex_unlock(lock);
+		return IRQ_NONE;
+	}
+
+	ret = rv3029_read_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
+	if (ret) {
+		dev_warn(dev, "Read IRQ Flags Register error %d\n", ret);
+		mutex_unlock(lock);
+		return IRQ_NONE;
+	}
+
+	if (flags & RV3029_IRQ_FLAGS_AF) {
+		flags &= ~RV3029_IRQ_FLAGS_AF;
+		controls &= ~RV3029_IRQ_CTRL_AIE;
+		events |= RTC_AF;
+	}
+
+	if (events) {
+		rtc_update_irq(rv3029->rtc, 1, events);
+		rv3029_write_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
+		rv3029_write_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
+	}
+	mutex_unlock(lock);
+
+	return IRQ_HANDLED;
+}
+
+static int rv3029_read_time(struct device *dev, struct rtc_time *tm)
+{
+	u8 buf[1];
+	int ret;
+	u8 regs[RV3029_WATCH_SECTION_LEN] = { 0, };
+
+	ret = rv3029_get_sr(dev, buf);
+	if (ret < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return -EIO;
+	}
+
+	ret = rv3029_read_regs(dev, RV3029_W_SEC, regs,
+			       RV3029_WATCH_SECTION_LEN);
+	if (ret < 0) {
+		dev_err(dev, "%s: reading RTC section failed\n", __func__);
+		return ret;
+	}
+
+	tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
+	tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
+
+	/* HR field has a more complex interpretation */
+	{
+		const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
+
+		if (_hr & RV3029_REG_HR_12_24) {
+			/* 12h format */
+			tm->tm_hour = bcd2bin(_hr & 0x1f);
+			if (_hr & RV3029_REG_HR_PM)	/* PM flag set */
+				tm->tm_hour += 12;
+		} else /* 24h format */
+			tm->tm_hour = bcd2bin(_hr & 0x3f);
+	}
+
+	tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
+	tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
+	tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 100;
+	tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
+
+	return 0;
+}
+
+static int rv3029_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct rtc_time *const tm = &alarm->time;
+	int ret;
+	u8 regs[8], controls, flags;
+
+	ret = rv3029_get_sr(dev, regs);
+	if (ret < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return -EIO;
+	}
+
+	ret = rv3029_read_regs(dev, RV3029_A_SC, regs,
+			       RV3029_ALARM_SECTION_LEN);
+
+	if (ret < 0) {
+		dev_err(dev, "%s: reading alarm section failed\n", __func__);
+		return ret;
+	}
+
+	ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
+	if (ret) {
+		dev_err(dev, "Read IRQ Control Register error %d\n", ret);
+		return ret;
+	}
+	ret = rv3029_read_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
+	if (ret < 0) {
+		dev_err(dev, "Read IRQ Flags Register error %d\n", ret);
+		return ret;
+	}
+
+	tm->tm_sec = bcd2bin(regs[RV3029_A_SC - RV3029_A_SC] & 0x7f);
+	tm->tm_min = bcd2bin(regs[RV3029_A_MN - RV3029_A_SC] & 0x7f);
+	tm->tm_hour = bcd2bin(regs[RV3029_A_HR - RV3029_A_SC] & 0x3f);
+	tm->tm_mday = bcd2bin(regs[RV3029_A_DT - RV3029_A_SC] & 0x3f);
+	tm->tm_mon = bcd2bin(regs[RV3029_A_MO - RV3029_A_SC] & 0x1f) - 1;
+	tm->tm_year = bcd2bin(regs[RV3029_A_YR - RV3029_A_SC] & 0x7f) + 100;
+	tm->tm_wday = bcd2bin(regs[RV3029_A_DW - RV3029_A_SC] & 0x07) - 1;
+
+	alarm->enabled = !!(controls & RV3029_IRQ_CTRL_AIE);
+	alarm->pending = (flags & RV3029_IRQ_FLAGS_AF) && alarm->enabled;
+
+	return 0;
+}
+
+static int rv3029_alarm_irq_enable(struct device *dev, unsigned int enable)
+{
+	int ret;
+	u8 controls;
+
+	ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
+	if (ret < 0) {
+		dev_warn(dev, "Read IRQ Control Register error %d\n", ret);
+		return ret;
+	}
+
+	/* enable/disable AIE irq */
+	if (enable)
+		controls |= RV3029_IRQ_CTRL_AIE;
+	else
+		controls &= ~RV3029_IRQ_CTRL_AIE;
+
+	ret = rv3029_write_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
+	if (ret < 0) {
+		dev_err(dev, "can't update INT reg\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rv3029_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct rtc_time *const tm = &alarm->time;
+	int ret;
+	u8 regs[8];
+
+	/*
+	 * The clock has an 8 bit wide bcd-coded register (they never learn)
+	 * for the year. tm_year is an offset from 1900 and we are interested
+	 * in the 2000-2099 range, so any value less than 100 is invalid.
+	*/
+	if (tm->tm_year < 100)
+		return -EINVAL;
+
+	ret = rv3029_get_sr(dev, regs);
+	if (ret < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return -EIO;
+	}
+
+	/* Activate all the alarms with AE_x bit */
+	regs[RV3029_A_SC - RV3029_A_SC] = bin2bcd(tm->tm_sec) | RV3029_A_AE_X;
+	regs[RV3029_A_MN - RV3029_A_SC] = bin2bcd(tm->tm_min) | RV3029_A_AE_X;
+	regs[RV3029_A_HR - RV3029_A_SC] = (bin2bcd(tm->tm_hour) & 0x3f)
+		| RV3029_A_AE_X;
+	regs[RV3029_A_DT - RV3029_A_SC] = (bin2bcd(tm->tm_mday) & 0x3f)
+		| RV3029_A_AE_X;
+	regs[RV3029_A_MO - RV3029_A_SC] = (bin2bcd(tm->tm_mon + 1) & 0x1f)
+		| RV3029_A_AE_X;
+	regs[RV3029_A_DW - RV3029_A_SC] = (bin2bcd(tm->tm_wday + 1) & 0x7)
+		| RV3029_A_AE_X;
+	regs[RV3029_A_YR - RV3029_A_SC] = (bin2bcd(tm->tm_year - 100))
+		| RV3029_A_AE_X;
+
+	/* Write the alarm */
+	ret = rv3029_write_regs(dev, RV3029_A_SC, regs,
+				RV3029_ALARM_SECTION_LEN);
+	if (ret < 0)
+		return ret;
+
+	if (alarm->enabled) {
+		/* enable AIE irq */
+		ret = rv3029_alarm_irq_enable(dev, 1);
+		if (ret)
+			return ret;
+	} else {
+		/* disable AIE irq */
+		ret = rv3029_alarm_irq_enable(dev, 0);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int rv3029_set_time(struct device *dev, struct rtc_time *tm)
+{
+	u8 regs[8];
+	int ret;
+
+	/*
+	 * The clock has an 8 bit wide bcd-coded register (they never learn)
+	 * for the year. tm_year is an offset from 1900 and we are interested
+	 * in the 2000-2099 range, so any value less than 100 is invalid.
+	*/
+	if (tm->tm_year < 100)
+		return -EINVAL;
+
+	regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
+	regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
+	regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
+	regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
+	regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
+	regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
+	regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 100);
+
+	ret = rv3029_write_regs(dev, RV3029_W_SEC, regs,
+				RV3029_WATCH_SECTION_LEN);
+	if (ret < 0)
+		return ret;
+
+	ret = rv3029_get_sr(dev, regs);
+	if (ret < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return ret;
+	}
+	/* clear PON bit */
+	ret = rv3029_set_sr(dev, (regs[0] & ~RV3029_STATUS_PON));
+	if (ret < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct rv3029_trickle_tab_elem {
+	u32 r;		/* resistance in ohms */
+	u8 conf;	/* trickle config bits */
+} rv3029_trickle_tab[] = {
+	{
+		.r	= 1076,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
+			  RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
+	}, {
+		.r	= 1091,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
+			  RV3029_TRICKLE_20K,
+	}, {
+		.r	= 1137,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
+			  RV3029_TRICKLE_80K,
+	}, {
+		.r	= 1154,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,
+	}, {
+		.r	= 1371,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |
+			  RV3029_TRICKLE_80K,
+	}, {
+		.r	= 1395,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,
+	}, {
+		.r	= 1472,
+		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,
+	}, {
+		.r	= 1500,
+		.conf	= RV3029_TRICKLE_1K,
+	}, {
+		.r	= 3810,
+		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |
+			  RV3029_TRICKLE_80K,
+	}, {
+		.r	= 4000,
+		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,
+	}, {
+		.r	= 4706,
+		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,
+	}, {
+		.r	= 5000,
+		.conf	= RV3029_TRICKLE_5K,
+	}, {
+		.r	= 16000,
+		.conf	= RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
+	}, {
+		.r	= 20000,
+		.conf	= RV3029_TRICKLE_20K,
+	}, {
+		.r	= 80000,
+		.conf	= RV3029_TRICKLE_80K,
+	},
+};
+
+static void rv3029_trickle_config(struct device *dev)
+{
+	struct device_node *of_node = dev->of_node;
+	const struct rv3029_trickle_tab_elem *elem;
+	int i, err;
+	u32 ohms;
+	u8 trickle_set_bits;
+
+	if (!of_node)
+		return;
+
+	/* Configure the trickle charger. */
+	err = of_property_read_u32(of_node, "trickle-resistor-ohms", &ohms);
+	if (err) {
+		/* Disable trickle charger. */
+		trickle_set_bits = 0;
+	} else {
+		/* Enable trickle charger. */
+		for (i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++) {
+			elem = &rv3029_trickle_tab[i];
+			if (elem->r >= ohms)
+				break;
+		}
+		trickle_set_bits = elem->conf;
+		dev_info(dev,
+			 "Trickle charger enabled at %d ohms resistance.\n",
+			 elem->r);
+	}
+	err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
+					RV3029_TRICKLE_MASK,
+					trickle_set_bits);
+	if (err < 0)
+		dev_err(dev, "Failed to update trickle charger config\n");
+}
+
+#ifdef CONFIG_RTC_DRV_RV3029_HWMON
+
+static int rv3029_read_temp(struct device *dev, int *temp_mC)
+{
+	int ret;
+	u8 temp;
+
+	ret = rv3029_read_regs(dev, RV3029_TEMP_PAGE, &temp, 1);
+	if (ret < 0)
+		return ret;
+
+	*temp_mC = ((int)temp - 60) * 1000;
+
+	return 0;
+}
+
+static ssize_t rv3029_hwmon_show_temp(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	int ret, temp_mC;
+
+	ret = rv3029_read_temp(dev, &temp_mC);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", temp_mC);
+}
+
+static ssize_t rv3029_hwmon_set_update_interval(struct device *dev,
+						struct device_attribute *attr,
+						const char *buf,
+						size_t count)
+{
+	unsigned long interval_ms;
+	int ret;
+	u8 th_set_bits = 0;
+
+	ret = kstrtoul(buf, 10, &interval_ms);
+	if (ret < 0)
+		return ret;
+
+	if (interval_ms != 0) {
+		th_set_bits |= RV3029_EECTRL_THE;
+		if (interval_ms >= 16000)
+			th_set_bits |= RV3029_EECTRL_THP;
+	}
+	ret = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
+					RV3029_EECTRL_THE | RV3029_EECTRL_THP,
+					th_set_bits);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static ssize_t rv3029_hwmon_show_update_interval(struct device *dev,
+						 struct device_attribute *attr,
+						 char *buf)
+{
+	int ret, interval_ms;
+	u8 eectrl;
+
+	ret = rv3029_eeprom_read(dev, RV3029_CONTROL_E2P_EECTRL,
+				 &eectrl, 1);
+	if (ret < 0)
+		return ret;
+
+	if (eectrl & RV3029_EECTRL_THE) {
+		if (eectrl & RV3029_EECTRL_THP)
+			interval_ms = 16000;
+		else
+			interval_ms = 1000;
+	} else {
+		interval_ms = 0;
+	}
+
+	return sprintf(buf, "%d\n", interval_ms);
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, rv3029_hwmon_show_temp,
+			  NULL, 0);
+static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
+			  rv3029_hwmon_show_update_interval,
+			  rv3029_hwmon_set_update_interval, 0);
+
+static struct attribute *rv3029_hwmon_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_update_interval.dev_attr.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(rv3029_hwmon);
+
+static void rv3029_hwmon_register(struct device *dev, const char *name)
+{
+	struct rv3029_data *rv3029 = dev_get_drvdata(dev);
+	struct device *hwmon_dev;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, name, rv3029,
+							   rv3029_hwmon_groups);
+	if (IS_ERR(hwmon_dev)) {
+		dev_warn(dev, "unable to register hwmon device %ld\n",
+			 PTR_ERR(hwmon_dev));
+	}
+}
+
+#else /* CONFIG_RTC_DRV_RV3029_HWMON */
+
+static void rv3029_hwmon_register(struct device *dev, const char *name)
+{
+}
+
+#endif /* CONFIG_RTC_DRV_RV3029_HWMON */
+
+static struct rtc_class_ops rv3029_rtc_ops = {
+	.read_time	= rv3029_read_time,
+	.set_time	= rv3029_set_time,
+};
+
+static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
+			const char *name)
+{
+	struct rv3029_data *rv3029;
+	int rc = 0;
+	u8 buf[1];
+
+	rv3029 = devm_kzalloc(dev, sizeof(*rv3029), GFP_KERNEL);
+	if (!rv3029)
+		return -ENOMEM;
+
+	rv3029->regmap = regmap;
+	rv3029->irq = irq;
+	rv3029->dev = dev;
+	dev_set_drvdata(dev, rv3029);
+
+	rc = rv3029_get_sr(dev, buf);
+	if (rc < 0) {
+		dev_err(dev, "reading status failed\n");
+		return rc;
+	}
+
+	rv3029_trickle_config(dev);
+	rv3029_hwmon_register(dev, name);
+
+	rv3029->rtc = devm_rtc_device_register(dev, name, &rv3029_rtc_ops,
+					       THIS_MODULE);
+	if (IS_ERR(rv3029->rtc)) {
+		dev_err(dev, "unable to register the class device\n");
+		return PTR_ERR(rv3029->rtc);
+	}
+
+	if (rv3029->irq > 0) {
+		rc = devm_request_threaded_irq(dev, rv3029->irq,
+					       NULL, rv3029_handle_irq,
+					       IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					       "rv3029", dev);
+		if (rc) {
+			dev_warn(dev, "unable to request IRQ, alarms disabled\n");
+			rv3029->irq = 0;
+		} else {
+			rv3029_rtc_ops.read_alarm = rv3029_read_alarm;
+			rv3029_rtc_ops.set_alarm = rv3029_set_alarm;
+			rv3029_rtc_ops.alarm_irq_enable = rv3029_alarm_irq_enable;
+		}
+	}
+
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_I2C)
+
+static int rv3029_i2c_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+	};
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
+				     I2C_FUNC_SMBUS_BYTE)) {
+		dev_err(&client->dev, "Adapter does not support SMBUS_I2C_BLOCK or SMBUS_I2C_BYTE\n");
+		return -ENODEV;
+	}
+
+	regmap = devm_regmap_init_i2c(client, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return rv3029_probe(&client->dev, regmap, client->irq, client->name);
+}
+
+static const struct i2c_device_id rv3029_id[] = {
+	{ "rv3029", 0 },
+	{ "rv3029c2", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, rv3029_id);
+
+static const struct of_device_id rv3029_of_match[] = {
+	{ .compatible = "microcrystal,rv3029" },
+	/* Backward compatibility only, do not use compatibles below: */
+	{ .compatible = "rv3029" },
+	{ .compatible = "rv3029c2" },
+	{ .compatible = "mc,rv3029c2" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rv3029_of_match);
+
+static struct i2c_driver rv3029_driver = {
+	.driver = {
+		.name = "rtc-rv3029c2",
+		.of_match_table = of_match_ptr(rv3029_of_match),
+	},
+	.probe		= rv3029_i2c_probe,
+	.id_table	= rv3029_id,
+};
+
+static int rv3029_register_driver(void)
+{
+	return i2c_add_driver(&rv3029_driver);
+}
+
+static void rv3029_unregister_driver(void)
+{
+	i2c_del_driver(&rv3029_driver);
+}
+
+#else
+
+static int rv3029_register_driver(void)
+{
+	return 0;
+}
+
+static void rv3029_unregister_driver(void)
+{
+}
+
+#endif
+
+#if IS_ENABLED(CONFIG_SPI_MASTER)
+
+static int rv3049_probe(struct spi_device *spi)
+{
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+	};
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_spi(spi, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return rv3029_probe(&spi->dev, regmap, spi->irq, "rv3049");
+}
+
+static struct spi_driver rv3049_driver = {
+	.driver = {
+		.name    = "rv3049",
+	},
+	.probe   = rv3049_probe,
+};
+
+static int rv3049_register_driver(void)
+{
+	return spi_register_driver(&rv3049_driver);
+}
+
+static void rv3049_unregister_driver(void)
+{
+	spi_unregister_driver(&rv3049_driver);
+}
+
+#else
+
+static int rv3049_register_driver(void)
+{
+	return 0;
+}
+
+static void rv3049_unregister_driver(void)
+{
+}
+
+#endif
+
+static int __init rv30x9_init(void)
+{
+	int ret;
+
+	ret = rv3029_register_driver();
+	if (ret) {
+		pr_err("Failed to register rv3029 driver: %d\n", ret);
+		return ret;
+	}
+
+	ret = rv3049_register_driver();
+	if (ret) {
+		pr_err("Failed to register rv3049 driver: %d\n", ret);
+		rv3029_unregister_driver();
+	}
+
+	return ret;
+}
+module_init(rv30x9_init)
+
+static void __exit rv30x9_exit(void)
+{
+	rv3049_unregister_driver();
+	rv3029_unregister_driver();
+}
+module_exit(rv30x9_exit)
+
+MODULE_AUTHOR("Gregory Hermant <gregory.hermant@calao-systems.com>");
+MODULE_AUTHOR("Michael Buesch <m@bues.ch>");
+MODULE_DESCRIPTION("Micro Crystal RV3029/RV3049 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:rv3049");