This is a note to let you know that I've just added the patch titled
hwmon: (f71882fg) Fix negative temperature
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
hwmon-f71882fg-fix-negative-temperature.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 86911354a087a3cfa559a0eb55fb01f065d65f9d
Author: Ji-Ze Hong (Peter Hong) <hpeter@xxxxxxxxx>
Date: Mon Apr 18 17:07:06 2022 +0800
hwmon: (f71882fg) Fix negative temperature
[ Upstream commit 4aaaaf0f279836f06d3b9d0ffeec7a1e1a04ceef ]
All temperature of Fintek superio hwmonitor that using 1-byte reg will use
2's complement.
In show_temp()
temp = data->temp[nr] * 1000;
When data->temp[nr] read as 255, it indicate -1C, but this code will report
255C to userspace. It'll be ok when change to:
temp = ((s8)data->temp[nr]) * 1000;
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220418090706.6339-1-hpeter+linux_kernel@xxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/hwmon/f71882fg.c b/drivers/hwmon/f71882fg.c
index cb28e4b4fb10..b87ca56fb774 100644
--- a/drivers/hwmon/f71882fg.c
+++ b/drivers/hwmon/f71882fg.c
@@ -1590,8 +1590,9 @@ static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
temp *= 125;
if (sign)
temp -= 128000;
- } else
- temp = data->temp[nr] * 1000;
+ } else {
+ temp = ((s8)data->temp[nr]) * 1000;
+ }
return sprintf(buf, "%d\n", temp);
}
