Commit 9a3dce62 authored by Zhuang Yuyao's avatar Zhuang Yuyao Committed by Alexandre Belloni
Browse files

rtc: ds1307: ds3231 temperature s16 overflow 



while retrieving temperature from ds3231, the result may be overflow
since s16 is too small for a multiplication with 250.

ie. if temp_buf[0] == 0x2d, the result (s16 temp) will be negative.

Signed-off-by: default avatarAkinobu Mita <akinobu.mita@gmail.com>
Tested-by: default avatarMichael Tatarinov <kukabu@gmail.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
parent 00c9329e

drivers/rtc/rtc-ds1307.c

+2 −2
Original line number Diff line number Diff line
@@ -863,7 +863,7 @@ out: 
 * A user-initiated temperature conversion is not started by this function,

 * so the temperature is updated once every 64 seconds.

 */

static int ds3231_hwmon_read_temp(struct device *dev, s16 *mC)

static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)

{

	struct ds1307 *ds1307 = dev_get_drvdata(dev);

	u8 temp_buf[2];
@@ -892,7 +892,7 @@ static ssize_t ds3231_hwmon_show_temp(struct device *dev, 
				struct device_attribute *attr, char *buf)

{

	int ret;

	s16 temp;

	s32 temp;



	ret = ds3231_hwmon_read_temp(dev, &temp);

	if (ret)

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