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Commit 042fa8c7 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

rtc: ds1307: remove regs member 



ds1307->regs is never used before being read or initialized locally. There
is no point in keeping a copy in memory.

Also limit the size of the read buffer to what is really used, rename buf
to regs for consistency and use sizeof() where possible.

Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
parent ae930c91

drivers/rtc/rtc-ds1307.c

+107 −100
Original line number Diff line number Diff line
@@ -116,7 +116,6 @@ enum ds_type { 




struct ds1307 {

	u8			regs[11];

	struct nvmem_config	nvmem_cfg;

	enum ds_type		type;

	unsigned long		flags;
@@ -397,34 +396,36 @@ static int ds1307_get_time(struct device *dev, struct rtc_time *t) 
	struct ds1307	*ds1307 = dev_get_drvdata(dev);

	int		tmp, ret;

	const struct chip_desc *chip = &chips[ds1307->type];

	u8 regs[7];



	/* read the RTC date and time registers all at once */

	ret = regmap_bulk_read(ds1307->regmap, chip->offset, ds1307->regs, 7);

	ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs,

			       sizeof(regs));

	if (ret) {

		dev_err(dev, "%s error %d\n", "read", ret);

		return ret;

	}



	dev_dbg(dev, "%s: %7ph\n", "read", ds1307->regs);

	dev_dbg(dev, "%s: %7ph\n", "read", regs);



	/* if oscillator fail bit is set, no data can be trusted */

	if (ds1307->type == m41t0 &&

	    ds1307->regs[DS1307_REG_MIN] & M41T0_BIT_OF) {

	    regs[DS1307_REG_MIN] & M41T0_BIT_OF) {

		dev_warn_once(dev, "oscillator failed, set time!\n");

		return -EINVAL;

	}



	t->tm_sec = bcd2bin(ds1307->regs[DS1307_REG_SECS] & 0x7f);

	t->tm_min = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);

	tmp = ds1307->regs[DS1307_REG_HOUR] & 0x3f;

	t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f);

	t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f);

	tmp = regs[DS1307_REG_HOUR] & 0x3f;

	t->tm_hour = bcd2bin(tmp);

	t->tm_wday = bcd2bin(ds1307->regs[DS1307_REG_WDAY] & 0x07) - 1;

	t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);

	tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;

	t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1;

	t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f);

	tmp = regs[DS1307_REG_MONTH] & 0x1f;

	t->tm_mon = bcd2bin(tmp) - 1;

	t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_YEAR]) + 100;

	t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100;



	if (ds1307->regs[chip->century_reg] & chip->century_bit &&

	if (regs[chip->century_reg] & chip->century_bit &&

	    IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY))

		t->tm_year += 100;
@@ -444,7 +445,7 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t) 
	const struct chip_desc *chip = &chips[ds1307->type];

	int		result;

	int		tmp;

	u8		*buf = ds1307->regs;

	u8		regs[7];



	dev_dbg(dev, "%s secs=%d, mins=%d, "

		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
@@ -463,35 +464,36 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t) 
		return -EINVAL;

#endif



	buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);

	buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);

	buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);

	buf[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);

	buf[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);

	buf[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);

	regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec);

	regs[DS1307_REG_MIN] = bin2bcd(t->tm_min);

	regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);

	regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);

	regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);

	regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);



	/* assume 20YY not 19YY */

	tmp = t->tm_year - 100;

	buf[DS1307_REG_YEAR] = bin2bcd(tmp);

	regs[DS1307_REG_YEAR] = bin2bcd(tmp);



	if (chip->century_enable_bit)

		buf[chip->century_reg] |= chip->century_enable_bit;

		regs[chip->century_reg] |= chip->century_enable_bit;

	if (t->tm_year > 199 && chip->century_bit)

		buf[chip->century_reg] |= chip->century_bit;

		regs[chip->century_reg] |= chip->century_bit;



	if (ds1307->type == mcp794xx) {

		/*

		 * these bits were cleared when preparing the date/time

		 * values and need to be set again before writing the

		 * buffer out to the device.

		 * regsfer out to the device.

		 */

		buf[DS1307_REG_SECS] |= MCP794XX_BIT_ST;

		buf[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;

		regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST;

		regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;

	}



	dev_dbg(dev, "%s: %7ph\n", "write", buf);

	dev_dbg(dev, "%s: %7ph\n", "write", regs);



	result = regmap_bulk_write(ds1307->regmap, chip->offset, buf, 7);

	result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,

				   sizeof(regs));

	if (result) {

		dev_err(dev, "%s error %d\n", "write", result);

		return result;
@@ -503,33 +505,34 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
{

	struct ds1307		*ds1307 = dev_get_drvdata(dev);

	int			ret;

	u8			regs[9];



	if (!test_bit(HAS_ALARM, &ds1307->flags))

		return -EINVAL;



	/* read all ALARM1, ALARM2, and status registers at once */

	ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS,

			       ds1307->regs, 9);

			       regs, sizeof(regs));

	if (ret) {

		dev_err(dev, "%s error %d\n", "alarm read", ret);

		return ret;

	}



	dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",

		&ds1307->regs[0], &ds1307->regs[4], &ds1307->regs[7]);

		&regs[0], &regs[4], &regs[7]);



	/*

	 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,

	 * and that all four fields are checked matches

	 */

	t->time.tm_sec = bcd2bin(ds1307->regs[0] & 0x7f);

	t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);

	t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);

	t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);

	t->time.tm_sec = bcd2bin(regs[0] & 0x7f);

	t->time.tm_min = bcd2bin(regs[1] & 0x7f);

	t->time.tm_hour = bcd2bin(regs[2] & 0x3f);

	t->time.tm_mday = bcd2bin(regs[3] & 0x3f);



	/* ... and status */

	t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);

	t->pending = !!(ds1307->regs[8] & DS1337_BIT_A1I);

	t->enabled = !!(regs[7] & DS1337_BIT_A1IE);

	t->pending = !!(regs[8] & DS1337_BIT_A1I);



	dev_dbg(dev, "%s secs=%d, mins=%d, "

		"hours=%d, mday=%d, enabled=%d, pending=%d\n",
@@ -543,7 +546,7 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)

{

	struct ds1307		*ds1307 = dev_get_drvdata(dev);

	unsigned char		*buf = ds1307->regs;

	unsigned char		regs[9];

	u8			control, status;

	int			ret;
@@ -557,33 +560,35 @@ static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
		t->enabled, t->pending);



	/* read current status of both alarms and the chip */

	ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, buf, 9);

	ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,

			       sizeof(regs));

	if (ret) {

		dev_err(dev, "%s error %d\n", "alarm write", ret);

		return ret;

	}

	control = ds1307->regs[7];

	status = ds1307->regs[8];

	control = regs[7];

	status = regs[8];



	dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",

		&ds1307->regs[0], &ds1307->regs[4], control, status);

		&regs[0], &regs[4], control, status);



	/* set ALARM1, using 24 hour and day-of-month modes */

	buf[0] = bin2bcd(t->time.tm_sec);

	buf[1] = bin2bcd(t->time.tm_min);

	buf[2] = bin2bcd(t->time.tm_hour);

	buf[3] = bin2bcd(t->time.tm_mday);

	regs[0] = bin2bcd(t->time.tm_sec);

	regs[1] = bin2bcd(t->time.tm_min);

	regs[2] = bin2bcd(t->time.tm_hour);

	regs[3] = bin2bcd(t->time.tm_mday);



	/* set ALARM2 to non-garbage */

	buf[4] = 0;

	buf[5] = 0;

	buf[6] = 0;

	regs[4] = 0;

	regs[5] = 0;

	regs[6] = 0;



	/* disable alarms */

	buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);

	buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);

	regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);

	regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);



	ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, buf, 9);

	ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,

				sizeof(regs));

	if (ret) {

		dev_err(dev, "can't set alarm time\n");

		return ret;
@@ -592,8 +597,8 @@ static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
	/* optionally enable ALARM1 */

	if (t->enabled) {

		dev_dbg(dev, "alarm IRQ armed\n");

		buf[7] |= DS1337_BIT_A1IE;	/* only ALARM1 is used */

		regmap_write(ds1307->regmap, DS1337_REG_CONTROL, buf[7]);

		regs[7] |= DS1337_BIT_A1IE;	/* only ALARM1 is used */

		regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]);

	}



	return 0;
@@ -830,26 +835,27 @@ static irqreturn_t mcp794xx_irq(int irq, void *dev_id) 
static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)

{

	struct ds1307 *ds1307 = dev_get_drvdata(dev);

	u8 *regs = ds1307->regs;

	u8 regs[10];

	int ret;



	if (!test_bit(HAS_ALARM, &ds1307->flags))

		return -EINVAL;



	/* Read control and alarm 0 registers. */

	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 10);

	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,

			       sizeof(regs));

	if (ret)

		return ret;



	t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);



	/* Report alarm 0 time assuming 24-hour and day-of-month modes. */

	t->time.tm_sec = bcd2bin(ds1307->regs[3] & 0x7f);

	t->time.tm_min = bcd2bin(ds1307->regs[4] & 0x7f);

	t->time.tm_hour = bcd2bin(ds1307->regs[5] & 0x3f);

	t->time.tm_wday = bcd2bin(ds1307->regs[6] & 0x7) - 1;

	t->time.tm_mday = bcd2bin(ds1307->regs[7] & 0x3f);

	t->time.tm_mon = bcd2bin(ds1307->regs[8] & 0x1f) - 1;

	t->time.tm_sec = bcd2bin(regs[3] & 0x7f);

	t->time.tm_min = bcd2bin(regs[4] & 0x7f);

	t->time.tm_hour = bcd2bin(regs[5] & 0x3f);

	t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1;

	t->time.tm_mday = bcd2bin(regs[7] & 0x3f);

	t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1;

	t->time.tm_year = -1;

	t->time.tm_yday = -1;

	t->time.tm_isdst = -1;
@@ -858,9 +864,9 @@ static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
		"enabled=%d polarity=%d irq=%d match=%d\n", __func__,

		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,

		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,

		!!(ds1307->regs[6] & MCP794XX_BIT_ALMX_POL),

		!!(ds1307->regs[6] & MCP794XX_BIT_ALMX_IF),

		(ds1307->regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);

		!!(regs[6] & MCP794XX_BIT_ALMX_POL),

		!!(regs[6] & MCP794XX_BIT_ALMX_IF),

		(regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);



	return 0;

}
@@ -868,7 +874,7 @@ static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) 
static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)

{

	struct ds1307 *ds1307 = dev_get_drvdata(dev);

	unsigned char *regs = ds1307->regs;

	unsigned char regs[10];

	int ret;



	if (!test_bit(HAS_ALARM, &ds1307->flags))
@@ -881,7 +887,8 @@ static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
		t->enabled, t->pending);



	/* Read control and alarm 0 registers. */

	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 10);

	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,

			       sizeof(regs));

	if (ret)

		return ret;
@@ -900,7 +907,8 @@ static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t) 
	/* Disable interrupt. We will not enable until completely programmed */

	regs[0] &= ~MCP794XX_BIT_ALM0_EN;



	ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs, 10);

	ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs,

				sizeof(regs));

	if (ret)

		return ret;
@@ -1344,7 +1352,7 @@ static int ds1307_probe(struct i2c_client *client, 
	const struct chip_desc	*chip;

	bool			want_irq;

	bool			ds1307_can_wakeup_device = false;

	unsigned char		*buf;

	unsigned char		regs[8];

	struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);

	struct rtc_time		tm;

	unsigned long		timestamp;
@@ -1400,8 +1408,6 @@ static int ds1307_probe(struct i2c_client *client, 
			     trickle_charger_setup);

	}



	buf = ds1307->regs;



#ifdef CONFIG_OF

/*

 * For devices with no IRQ directly connected to the SoC, the RTC chip
@@ -1423,15 +1429,15 @@ static int ds1307_probe(struct i2c_client *client, 
	case ds_3231:

		/* get registers that the "rtc" read below won't read... */

		err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL,

				       buf, 2);

				       regs, 2);

		if (err) {

			dev_dbg(ds1307->dev, "read error %d\n", err);

			goto exit;

		}



		/* oscillator off?  turn it on, so clock can tick. */

		if (ds1307->regs[0] & DS1337_BIT_nEOSC)

			ds1307->regs[0] &= ~DS1337_BIT_nEOSC;

		if (regs[0] & DS1337_BIT_nEOSC)

			regs[0] &= ~DS1337_BIT_nEOSC;



		/*

		 * Using IRQ or defined as wakeup-source?
@@ -1440,77 +1446,77 @@ static int ds1307_probe(struct i2c_client *client, 
		 * running on Vbackup (BBSQI/BBSQW)

		 */

		if (want_irq || ds1307_can_wakeup_device) {

			ds1307->regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;

			ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);

			regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;

			regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);

		}



		regmap_write(ds1307->regmap, DS1337_REG_CONTROL,

			     ds1307->regs[0]);

			     regs[0]);



		/* oscillator fault?  clear flag, and warn */

		if (ds1307->regs[1] & DS1337_BIT_OSF) {

		if (regs[1] & DS1337_BIT_OSF) {

			regmap_write(ds1307->regmap, DS1337_REG_STATUS,

				     ds1307->regs[1] & ~DS1337_BIT_OSF);

				     regs[1] & ~DS1337_BIT_OSF);

			dev_warn(ds1307->dev, "SET TIME!\n");

		}

		break;



	case rx_8025:

		err = regmap_bulk_read(ds1307->regmap,

				       RX8025_REG_CTRL1 << 4 | 0x08, buf, 2);

				       RX8025_REG_CTRL1 << 4 | 0x08, regs, 2);

		if (err) {

			dev_dbg(ds1307->dev, "read error %d\n", err);

			goto exit;

		}



		/* oscillator off?  turn it on, so clock can tick. */

		if (!(ds1307->regs[1] & RX8025_BIT_XST)) {

			ds1307->regs[1] |= RX8025_BIT_XST;

		if (!(regs[1] & RX8025_BIT_XST)) {

			regs[1] |= RX8025_BIT_XST;

			regmap_write(ds1307->regmap,

				     RX8025_REG_CTRL2 << 4 | 0x08,

				     ds1307->regs[1]);

				     regs[1]);

			dev_warn(ds1307->dev,

				 "oscillator stop detected - SET TIME!\n");

		}



		if (ds1307->regs[1] & RX8025_BIT_PON) {

			ds1307->regs[1] &= ~RX8025_BIT_PON;

		if (regs[1] & RX8025_BIT_PON) {

			regs[1] &= ~RX8025_BIT_PON;

			regmap_write(ds1307->regmap,

				     RX8025_REG_CTRL2 << 4 | 0x08,

				     ds1307->regs[1]);

				     regs[1]);

			dev_warn(ds1307->dev, "power-on detected\n");

		}



		if (ds1307->regs[1] & RX8025_BIT_VDET) {

			ds1307->regs[1] &= ~RX8025_BIT_VDET;

		if (regs[1] & RX8025_BIT_VDET) {

			regs[1] &= ~RX8025_BIT_VDET;

			regmap_write(ds1307->regmap,

				     RX8025_REG_CTRL2 << 4 | 0x08,

				     ds1307->regs[1]);

				     regs[1]);

			dev_warn(ds1307->dev, "voltage drop detected\n");

		}



		/* make sure we are running in 24hour mode */

		if (!(ds1307->regs[0] & RX8025_BIT_2412)) {

		if (!(regs[0] & RX8025_BIT_2412)) {

			u8 hour;



			/* switch to 24 hour mode */

			regmap_write(ds1307->regmap,

				     RX8025_REG_CTRL1 << 4 | 0x08,

				     ds1307->regs[0] | RX8025_BIT_2412);

				     regs[0] | RX8025_BIT_2412);



			err = regmap_bulk_read(ds1307->regmap,

					       RX8025_REG_CTRL1 << 4 | 0x08,

					       buf, 2);

					       regs, 2);

			if (err) {

				dev_dbg(ds1307->dev, "read error %d\n", err);

				goto exit;

			}



			/* correct hour */

			hour = bcd2bin(ds1307->regs[DS1307_REG_HOUR]);

			hour = bcd2bin(regs[DS1307_REG_HOUR]);

			if (hour == 12)

				hour = 0;

			if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)

			if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)

				hour += 12;



			regmap_write(ds1307->regmap,
@@ -1523,7 +1529,8 @@ static int ds1307_probe(struct i2c_client *client, 


read_rtc:

	/* read RTC registers */

	err = regmap_bulk_read(ds1307->regmap, chip->offset, buf, 8);

	err = regmap_bulk_read(ds1307->regmap, chip->offset, regs,

			       sizeof(regs));

	if (err) {

		dev_dbg(ds1307->dev, "read error %d\n", err);

		goto exit;
@@ -1534,7 +1541,7 @@ static int ds1307_probe(struct i2c_client *client, 
	 * specify the extra bits as must-be-zero, but there are

	 * still a few values that are clearly out-of-range.

	 */

	tmp = ds1307->regs[DS1307_REG_SECS];

	tmp = regs[DS1307_REG_SECS];

	switch (ds1307->type) {

	case ds_1307:

	case m41t0:
@@ -1553,9 +1560,9 @@ static int ds1307_probe(struct i2c_client *client, 
			regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);



		/* oscillator fault?  clear flag, and warn */

		if (ds1307->regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {

		if (regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {

			regmap_write(ds1307->regmap, DS1307_REG_CONTROL,

					ds1307->regs[DS1307_REG_CONTROL] &

					regs[DS1307_REG_CONTROL] &

					~DS1338_BIT_OSF);

			dev_warn(ds1307->dev, "SET TIME!\n");

			goto read_rtc;
@@ -1580,9 +1587,9 @@ static int ds1307_probe(struct i2c_client *client, 
		break;

	case mcp794xx:

		/* make sure that the backup battery is enabled */

		if (!(ds1307->regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {

		if (!(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {

			regmap_write(ds1307->regmap, DS1307_REG_WDAY,

				     ds1307->regs[DS1307_REG_WDAY] |

				     regs[DS1307_REG_WDAY] |

				     MCP794XX_BIT_VBATEN);

		}
@@ -1599,7 +1606,7 @@ static int ds1307_probe(struct i2c_client *client, 
		break;

	}



	tmp = ds1307->regs[DS1307_REG_HOUR];

	tmp = regs[DS1307_REG_HOUR];

	switch (ds1307->type) {

	case ds_1340:

	case m41t0:
@@ -1622,7 +1629,7 @@ static int ds1307_probe(struct i2c_client *client, 
		tmp = bcd2bin(tmp & 0x1f);

		if (tmp == 12)

			tmp = 0;

		if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)

		if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)

			tmp += 12;

		regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR,

			     bin2bcd(tmp));