Commit f308b682 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

rtc: ds1343: use burst write to set time 

To avoid possible race condition, use regmap_bulk_write to write all the
date/time registers at once instead of sequentially.

Link: https://lore.kernel.org/r/20191019204941.6203-3-alexandre.belloni@bootlin.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 8c9a88fa

drivers/rtc/rtc-ds1343.c

+12 −40
Original line number Diff line number Diff line
@@ -236,46 +236,18 @@ static int ds1343_read_time(struct device *dev, struct rtc_time *dt) 
static int ds1343_set_time(struct device *dev, struct rtc_time *dt)

{

	struct ds1343_priv *priv = dev_get_drvdata(dev);

	int res;



	res = regmap_write(priv->map, DS1343_SECONDS_REG,

				bin2bcd(dt->tm_sec));

	if (res)

		return res;



	res = regmap_write(priv->map, DS1343_MINUTES_REG,

				bin2bcd(dt->tm_min));

	if (res)

		return res;



	res = regmap_write(priv->map, DS1343_HOURS_REG,

				bin2bcd(dt->tm_hour) & 0x3F);

	if (res)

		return res;



	res = regmap_write(priv->map, DS1343_DAY_REG,

				bin2bcd(dt->tm_wday + 1));

	if (res)

		return res;



	res = regmap_write(priv->map, DS1343_DATE_REG,

				bin2bcd(dt->tm_mday));

	if (res)

		return res;



	res = regmap_write(priv->map, DS1343_MONTH_REG,

				bin2bcd(dt->tm_mon + 1));

	if (res)

		return res;



	dt->tm_year %= 100;



	res = regmap_write(priv->map, DS1343_YEAR_REG,

				bin2bcd(dt->tm_year));

	if (res)

		return res;



	return 0;

	u8 buf[7];



	buf[0] = bin2bcd(dt->tm_sec);

	buf[1] = bin2bcd(dt->tm_min);

	buf[2] = bin2bcd(dt->tm_hour) & 0x3F;

	buf[3] = bin2bcd(dt->tm_wday + 1);

	buf[4] = bin2bcd(dt->tm_mday);

	buf[5] = bin2bcd(dt->tm_mon + 1);

	buf[6] = bin2bcd(dt->tm_year - 100);



	return regmap_bulk_write(priv->map, DS1343_SECONDS_REG,

				 buf, sizeof(buf));

}



static int ds1343_update_alarm(struct device *dev)

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