Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 926 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
new file mode 100644
index 000000000..9b0138d07
--- /dev/null
+++ b/drivers/rtc/rtc-abx80x.c
@@ -0,0 +1,926 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * A driver for the I2C members of the Abracon AB x8xx RTC family,
+ * and compatible: AB 1805 and AB 0805
+ *
+ * Copyright 2014-2015 Macq S.A.
+ *
+ * Author: Philippe De Muyter <phdm@macqel.be>
+ * Author: Alexandre Belloni <alexandre.belloni@bootlin.com>
+ *
+ */
+
+#include <linux/bcd.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/rtc.h>
+#include <linux/watchdog.h>
+
+#define ABX8XX_REG_HTH		0x00
+#define ABX8XX_REG_SC		0x01
+#define ABX8XX_REG_MN		0x02
+#define ABX8XX_REG_HR		0x03
+#define ABX8XX_REG_DA		0x04
+#define ABX8XX_REG_MO		0x05
+#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_STATUS_BLF	BIT(4)
+#define ABX8XX_STATUS_WDT	BIT(6)
+
+#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_CTRL2	0x11
+#define ABX8XX_CTRL2_RSVD	BIT(5)
+
+#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_OSC		0x1c
+#define ABX8XX_OSC_FOS		BIT(3)
+#define ABX8XX_OSC_BOS		BIT(4)
+#define ABX8XX_OSC_ACAL_512	BIT(5)
+#define ABX8XX_OSC_ACAL_1024	BIT(6)
+
+#define ABX8XX_OSC_OSEL		BIT(7)
+
+#define ABX8XX_REG_OSS		0x1d
+#define ABX8XX_OSS_OF		BIT(1)
+#define ABX8XX_OSS_OMODE	BIT(4)
+
+#define ABX8XX_REG_WDT		0x1b
+#define ABX8XX_WDT_WDS		BIT(7)
+#define ABX8XX_WDT_BMB_MASK	0x7c
+#define ABX8XX_WDT_BMB_SHIFT	2
+#define ABX8XX_WDT_MAX_TIME	(ABX8XX_WDT_BMB_MASK >> ABX8XX_WDT_BMB_SHIFT)
+#define ABX8XX_WDT_WRB_MASK	0x03
+#define ABX8XX_WDT_WRB_1HZ	0x02
+
+#define ABX8XX_REG_CFG_KEY	0x1f
+#define ABX8XX_CFG_KEY_OSC	0xa1
+#define ABX8XX_CFG_KEY_MISC	0x9d
+
+#define ABX8XX_REG_ID0		0x28
+
+#define ABX8XX_REG_OUT_CTRL	0x30
+#define ABX8XX_OUT_CTRL_EXDS	BIT(4)
+
+#define ABX8XX_REG_TRICKLE	0x20
+#define ABX8XX_TRICKLE_CHARGE_ENABLE	0xa0
+#define ABX8XX_TRICKLE_STANDARD_DIODE	0x8
+#define ABX8XX_TRICKLE_SCHOTTKY_DIODE	0x4
+
+static u8 trickle_resistors[] = {0, 3, 6, 11};
+
+enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,
+	AB1801, AB1803, AB1804, AB1805, RV1805, ABX80X};
+
+struct abx80x_cap {
+	u16 pn;
+	bool has_tc;
+	bool has_wdog;
+};
+
+static struct abx80x_cap abx80x_caps[] = {
+	[AB0801] = {.pn = 0x0801},
+	[AB0803] = {.pn = 0x0803},
+	[AB0804] = {.pn = 0x0804, .has_tc = true, .has_wdog = true},
+	[AB0805] = {.pn = 0x0805, .has_tc = true, .has_wdog = true},
+	[AB1801] = {.pn = 0x1801},
+	[AB1803] = {.pn = 0x1803},
+	[AB1804] = {.pn = 0x1804, .has_tc = true, .has_wdog = true},
+	[AB1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},
+	[RV1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},
+	[ABX80X] = {.pn = 0}
+};
+
+struct abx80x_priv {
+	struct rtc_device *rtc;
+	struct i2c_client *client;
+	struct watchdog_device wdog;
+};
+
+static int abx80x_write_config_key(struct i2c_client *client, u8 key)
+{
+	if (i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, key) < 0) {
+		dev_err(&client->dev, "Unable to write configuration key\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int abx80x_is_rc_mode(struct i2c_client *client)
+{
+	int flags = 0;
+
+	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
+	if (flags < 0) {
+		dev_err(&client->dev,
+			"Failed to read autocalibration attribute\n");
+		return flags;
+	}
+
+	return (flags & ABX8XX_OSS_OMODE) ? 1 : 0;
+}
+
+static int abx80x_enable_trickle_charger(struct i2c_client *client,
+					 u8 trickle_cfg)
+{
+	int err;
+
+	/*
+	 * Write the configuration key register to enable access to the Trickle
+	 * register
+	 */
+	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)
+		return -EIO;
+
+	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,
+					ABX8XX_TRICKLE_CHARGE_ENABLE |
+					trickle_cfg);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to write trickle register\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	unsigned char buf[8];
+	int err, flags, rc_mode = 0;
+
+	/* Read the Oscillator Failure only in XT mode */
+	rc_mode = abx80x_is_rc_mode(client);
+	if (rc_mode < 0)
+		return rc_mode;
+
+	if (!rc_mode) {
+		flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
+		if (flags < 0)
+			return flags;
+
+		if (flags & ABX8XX_OSS_OF) {
+			dev_err(dev, "Oscillator failure, data is invalid.\n");
+			return -EINVAL;
+		}
+	}
+
+	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,
+					    sizeof(buf), buf);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to read date\n");
+		return -EIO;
+	}
+
+	tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);
+	tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);
+	tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);
+	tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;
+	tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);
+	tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;
+	tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;
+
+	return 0;
+}
+
+static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	unsigned char buf[8];
+	int err, flags;
+
+	if (tm->tm_year < 100)
+		return -EINVAL;
+
+	buf[ABX8XX_REG_HTH] = 0;
+	buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);
+	buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);
+	buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);
+	buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);
+	buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);
+	buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);
+	buf[ABX8XX_REG_WD] = tm->tm_wday;
+
+	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,
+					     sizeof(buf), buf);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to write to date registers\n");
+		return -EIO;
+	}
+
+	/* Clear the OF bit of Oscillator Status Register */
+	flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
+	if (flags < 0)
+		return flags;
+
+	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS,
+					flags & ~ABX8XX_OSS_OF);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to write oscillator status register\n");
+		return err;
+	}
+
+	return 0;
+}
+
+static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
+{
+	struct i2c_client *client = dev_id;
+	struct abx80x_priv *priv = i2c_get_clientdata(client);
+	struct rtc_device *rtc = priv->rtc;
+	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);
+
+	/*
+	 * It is unclear if we'll get an interrupt before the external
+	 * reset kicks in.
+	 */
+	if (status & ABX8XX_STATUS_WDT)
+		dev_alert(&client->dev, "watchdog timeout interrupt.\n");
+
+	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_rtc_set_autocalibration(struct device *dev,
+					  int autocalibration)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int retval, flags = 0;
+
+	if ((autocalibration != 0) && (autocalibration != 1024) &&
+	    (autocalibration != 512)) {
+		dev_err(dev, "autocalibration value outside permitted range\n");
+		return -EINVAL;
+	}
+
+	flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
+	if (flags < 0)
+		return flags;
+
+	if (autocalibration == 0) {
+		flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024);
+	} else if (autocalibration == 1024) {
+		/* 1024 autocalibration is 0x10 */
+		flags |= ABX8XX_OSC_ACAL_1024;
+		flags &= ~(ABX8XX_OSC_ACAL_512);
+	} else {
+		/* 512 autocalibration is 0x11 */
+		flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512);
+	}
+
+	/* Unlock write access to Oscillator Control Register */
+	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)
+		return -EIO;
+
+	retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
+
+	return retval;
+}
+
+static int abx80x_rtc_get_autocalibration(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int flags = 0, autocalibration;
+
+	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
+	if (flags < 0)
+		return flags;
+
+	if (flags & ABX8XX_OSC_ACAL_512)
+		autocalibration = 512;
+	else if (flags & ABX8XX_OSC_ACAL_1024)
+		autocalibration = 1024;
+	else
+		autocalibration = 0;
+
+	return autocalibration;
+}
+
+static ssize_t autocalibration_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	int retval;
+	unsigned long autocalibration = 0;
+
+	retval = kstrtoul(buf, 10, &autocalibration);
+	if (retval < 0) {
+		dev_err(dev, "Failed to store RTC autocalibration attribute\n");
+		return -EINVAL;
+	}
+
+	retval = abx80x_rtc_set_autocalibration(dev->parent, autocalibration);
+
+	return retval ? retval : count;
+}
+
+static ssize_t autocalibration_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	int autocalibration = 0;
+
+	autocalibration = abx80x_rtc_get_autocalibration(dev->parent);
+	if (autocalibration < 0) {
+		dev_err(dev, "Failed to read RTC autocalibration\n");
+		sprintf(buf, "0\n");
+		return autocalibration;
+	}
+
+	return sprintf(buf, "%d\n", autocalibration);
+}
+
+static DEVICE_ATTR_RW(autocalibration);
+
+static ssize_t oscillator_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev->parent);
+	int retval, flags, rc_mode = 0;
+
+	if (strncmp(buf, "rc", 2) == 0) {
+		rc_mode = 1;
+	} else if (strncmp(buf, "xtal", 4) == 0) {
+		rc_mode = 0;
+	} else {
+		dev_err(dev, "Oscillator selection value outside permitted ones\n");
+		return -EINVAL;
+	}
+
+	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
+	if (flags < 0)
+		return flags;
+
+	if (rc_mode == 0)
+		flags &= ~(ABX8XX_OSC_OSEL);
+	else
+		flags |= (ABX8XX_OSC_OSEL);
+
+	/* Unlock write access on Oscillator Control register */
+	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)
+		return -EIO;
+
+	retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
+	if (retval < 0) {
+		dev_err(dev, "Failed to write Oscillator Control register\n");
+		return retval;
+	}
+
+	return retval ? retval : count;
+}
+
+static ssize_t oscillator_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	int rc_mode = 0;
+	struct i2c_client *client = to_i2c_client(dev->parent);
+
+	rc_mode = abx80x_is_rc_mode(client);
+
+	if (rc_mode < 0) {
+		dev_err(dev, "Failed to read RTC oscillator selection\n");
+		sprintf(buf, "\n");
+		return rc_mode;
+	}
+
+	if (rc_mode)
+		return sprintf(buf, "rc\n");
+	else
+		return sprintf(buf, "xtal\n");
+}
+
+static DEVICE_ATTR_RW(oscillator);
+
+static struct attribute *rtc_calib_attrs[] = {
+	&dev_attr_autocalibration.attr,
+	&dev_attr_oscillator.attr,
+	NULL,
+};
+
+static const struct attribute_group rtc_calib_attr_group = {
+	.attrs		= rtc_calib_attrs,
+};
+
+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 int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int status, tmp;
+
+	switch (cmd) {
+	case RTC_VL_READ:
+		status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+		if (status < 0)
+			return status;
+
+		tmp = status & ABX8XX_STATUS_BLF ? RTC_VL_BACKUP_LOW : 0;
+
+		return put_user(tmp, (unsigned int __user *)arg);
+
+	case RTC_VL_CLR:
+		status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+		if (status < 0)
+			return status;
+
+		status &= ~ABX8XX_STATUS_BLF;
+
+		tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
+		if (tmp < 0)
+			return tmp;
+
+		return 0;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+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,
+	.ioctl		= abx80x_ioctl,
+};
+
+static int abx80x_dt_trickle_cfg(struct i2c_client *client)
+{
+	struct device_node *np = client->dev.of_node;
+	const char *diode;
+	int trickle_cfg = 0;
+	int i, ret;
+	u32 tmp;
+
+	ret = of_property_read_string(np, "abracon,tc-diode", &diode);
+	if (ret)
+		return ret;
+
+	if (!strcmp(diode, "standard")) {
+		trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE;
+	} else if (!strcmp(diode, "schottky")) {
+		trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE;
+	} else {
+		dev_dbg(&client->dev, "Invalid tc-diode value: %s\n", diode);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < sizeof(trickle_resistors); i++)
+		if (trickle_resistors[i] == tmp)
+			break;
+
+	if (i == sizeof(trickle_resistors)) {
+		dev_dbg(&client->dev, "Invalid tc-resistor value: %u\n", tmp);
+		return -EINVAL;
+	}
+
+	return (trickle_cfg | i);
+}
+
+#ifdef CONFIG_WATCHDOG
+
+static inline u8 timeout_bits(unsigned int timeout)
+{
+	return ((timeout << ABX8XX_WDT_BMB_SHIFT) & ABX8XX_WDT_BMB_MASK) |
+		 ABX8XX_WDT_WRB_1HZ;
+}
+
+static int __abx80x_wdog_set_timeout(struct watchdog_device *wdog,
+				     unsigned int timeout)
+{
+	struct abx80x_priv *priv = watchdog_get_drvdata(wdog);
+	u8 val = ABX8XX_WDT_WDS | timeout_bits(timeout);
+
+	/*
+	 * Writing any timeout to the WDT register resets the watchdog timer.
+	 * Writing 0 disables it.
+	 */
+	return i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_WDT, val);
+}
+
+static int abx80x_wdog_set_timeout(struct watchdog_device *wdog,
+				   unsigned int new_timeout)
+{
+	int err = 0;
+
+	if (watchdog_hw_running(wdog))
+		err = __abx80x_wdog_set_timeout(wdog, new_timeout);
+
+	if (err == 0)
+		wdog->timeout = new_timeout;
+
+	return err;
+}
+
+static int abx80x_wdog_ping(struct watchdog_device *wdog)
+{
+	return __abx80x_wdog_set_timeout(wdog, wdog->timeout);
+}
+
+static int abx80x_wdog_start(struct watchdog_device *wdog)
+{
+	return __abx80x_wdog_set_timeout(wdog, wdog->timeout);
+}
+
+static int abx80x_wdog_stop(struct watchdog_device *wdog)
+{
+	return __abx80x_wdog_set_timeout(wdog, 0);
+}
+
+static const struct watchdog_info abx80x_wdog_info = {
+	.identity = "abx80x watchdog",
+	.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops abx80x_wdog_ops = {
+	.owner = THIS_MODULE,
+	.start = abx80x_wdog_start,
+	.stop = abx80x_wdog_stop,
+	.ping = abx80x_wdog_ping,
+	.set_timeout = abx80x_wdog_set_timeout,
+};
+
+static int abx80x_setup_watchdog(struct abx80x_priv *priv)
+{
+	priv->wdog.parent = &priv->client->dev;
+	priv->wdog.ops = &abx80x_wdog_ops;
+	priv->wdog.info = &abx80x_wdog_info;
+	priv->wdog.min_timeout = 1;
+	priv->wdog.max_timeout = ABX8XX_WDT_MAX_TIME;
+	priv->wdog.timeout = ABX8XX_WDT_MAX_TIME;
+
+	watchdog_set_drvdata(&priv->wdog, priv);
+
+	return devm_watchdog_register_device(&priv->client->dev, &priv->wdog);
+}
+#else
+static int abx80x_setup_watchdog(struct abx80x_priv *priv)
+{
+	return 0;
+}
+#endif
+
+static int abx80x_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct device_node *np = client->dev.of_node;
+	struct abx80x_priv *priv;
+	int i, data, err, trickle_cfg = -EINVAL;
+	char buf[7];
+	unsigned int part = id->driver_data;
+	unsigned int partnumber;
+	unsigned int majrev, minrev;
+	unsigned int lot;
+	unsigned int wafer;
+	unsigned int uid;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,
+					    sizeof(buf), buf);
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to read partnumber\n");
+		return -EIO;
+	}
+
+	partnumber = (buf[0] << 8) | buf[1];
+	majrev = buf[2] >> 3;
+	minrev = buf[2] & 0x7;
+	lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];
+	uid = ((buf[4] & 0x7f) << 8) | buf[5];
+	wafer = (buf[6] & 0x7c) >> 2;
+	dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
+		 partnumber, majrev, minrev, lot, wafer, uid);
+
+	data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);
+	if (data < 0) {
+		dev_err(&client->dev, "Unable to read control register\n");
+		return -EIO;
+	}
+
+	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
+					((data & ~(ABX8XX_CTRL_12_24 |
+						   ABX8XX_CTRL_ARST)) |
+					 ABX8XX_CTRL_WRITE));
+	if (err < 0) {
+		dev_err(&client->dev, "Unable to write control register\n");
+		return -EIO;
+	}
+
+	/* Configure RV1805 specifics */
+	if (part == RV1805) {
+		/*
+		 * Avoid accidentally entering test mode. This can happen
+		 * on the RV1805 in case the reserved bit 5 in control2
+		 * register is set. RV-1805-C3 datasheet indicates that
+		 * the bit should be cleared in section 11h - Control2.
+		 */
+		data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL2);
+		if (data < 0) {
+			dev_err(&client->dev,
+				"Unable to read control2 register\n");
+			return -EIO;
+		}
+
+		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL2,
+						data & ~ABX8XX_CTRL2_RSVD);
+		if (err < 0) {
+			dev_err(&client->dev,
+				"Unable to write control2 register\n");
+			return -EIO;
+		}
+
+		/*
+		 * Avoid extra power leakage. The RV1805 uses smaller
+		 * 10pin package and the EXTI input is not present.
+		 * Disable it to avoid leakage.
+		 */
+		data = i2c_smbus_read_byte_data(client, ABX8XX_REG_OUT_CTRL);
+		if (data < 0) {
+			dev_err(&client->dev,
+				"Unable to read output control register\n");
+			return -EIO;
+		}
+
+		/*
+		 * Write the configuration key register to enable access to
+		 * the config2 register
+		 */
+		if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)
+			return -EIO;
+
+		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OUT_CTRL,
+						data | ABX8XX_OUT_CTRL_EXDS);
+		if (err < 0) {
+			dev_err(&client->dev,
+				"Unable to write output control register\n");
+			return -EIO;
+		}
+	}
+
+	/* part autodetection */
+	if (part == ABX80X) {
+		for (i = 0; abx80x_caps[i].pn; i++)
+			if (partnumber == abx80x_caps[i].pn)
+				break;
+		if (abx80x_caps[i].pn == 0) {
+			dev_err(&client->dev, "Unknown part: %04x\n",
+				partnumber);
+			return -EINVAL;
+		}
+		part = i;
+	}
+
+	if (partnumber != abx80x_caps[part].pn) {
+		dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",
+			partnumber, abx80x_caps[part].pn);
+		return -EINVAL;
+	}
+
+	if (np && abx80x_caps[part].has_tc)
+		trickle_cfg = abx80x_dt_trickle_cfg(client);
+
+	if (trickle_cfg > 0) {
+		dev_info(&client->dev, "Enabling trickle charger: %02x\n",
+			 trickle_cfg);
+		abx80x_enable_trickle_charger(client, trickle_cfg);
+	}
+
+	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
+					BIT(2));
+	if (err)
+		return err;
+
+	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
+	if (priv == NULL)
+		return -ENOMEM;
+
+	priv->rtc = devm_rtc_allocate_device(&client->dev);
+	if (IS_ERR(priv->rtc))
+		return PTR_ERR(priv->rtc);
+
+	priv->rtc->ops = &abx80x_rtc_ops;
+	priv->client = client;
+
+	i2c_set_clientdata(client, priv);
+
+	if (abx80x_caps[part].has_wdog) {
+		err = abx80x_setup_watchdog(priv);
+		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,
+						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;
+		}
+	}
+
+	err = rtc_add_group(priv->rtc, &rtc_calib_attr_group);
+	if (err) {
+		dev_err(&client->dev, "Failed to create sysfs group: %d\n",
+			err);
+		return err;
+	}
+
+	return devm_rtc_register_device(priv->rtc);
+}
+
+static const struct i2c_device_id abx80x_id[] = {
+	{ "abx80x", ABX80X },
+	{ "ab0801", AB0801 },
+	{ "ab0803", AB0803 },
+	{ "ab0804", AB0804 },
+	{ "ab0805", AB0805 },
+	{ "ab1801", AB1801 },
+	{ "ab1803", AB1803 },
+	{ "ab1804", AB1804 },
+	{ "ab1805", AB1805 },
+	{ "rv1805", RV1805 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, abx80x_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id abx80x_of_match[] = {
+	{
+		.compatible = "abracon,abx80x",
+		.data = (void *)ABX80X
+	},
+	{
+		.compatible = "abracon,ab0801",
+		.data = (void *)AB0801
+	},
+	{
+		.compatible = "abracon,ab0803",
+		.data = (void *)AB0803
+	},
+	{
+		.compatible = "abracon,ab0804",
+		.data = (void *)AB0804
+	},
+	{
+		.compatible = "abracon,ab0805",
+		.data = (void *)AB0805
+	},
+	{
+		.compatible = "abracon,ab1801",
+		.data = (void *)AB1801
+	},
+	{
+		.compatible = "abracon,ab1803",
+		.data = (void *)AB1803
+	},
+	{
+		.compatible = "abracon,ab1804",
+		.data = (void *)AB1804
+	},
+	{
+		.compatible = "abracon,ab1805",
+		.data = (void *)AB1805
+	},
+	{
+		.compatible = "microcrystal,rv1805",
+		.data = (void *)RV1805
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, abx80x_of_match);
+#endif
+
+static struct i2c_driver abx80x_driver = {
+	.driver		= {
+		.name	= "rtc-abx80x",
+		.of_match_table = of_match_ptr(abx80x_of_match),
+	},
+	.probe		= abx80x_probe,
+	.id_table	= abx80x_id,
+};
+
+module_i2c_driver(abx80x_driver);
+
+MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
+MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
+MODULE_LICENSE("GPL v2");