| From fad311feab8af47fcc403d145e5f60a0157620d9 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 18 Apr 2022 17:07:06 +0800 |
| Subject: hwmon: (f71882fg) Fix negative temperature |
| |
| From: Ji-Ze Hong (Peter Hong) <hpeter@gmail.com> |
| |
| [ 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@gmail.com> |
| Link: https://lore.kernel.org/r/20220418090706.6339-1-hpeter+linux_kernel@gmail.com |
| Signed-off-by: Guenter Roeck <linux@roeck-us.net> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/hwmon/f71882fg.c | 5 +++-- |
| 1 file changed, 3 insertions(+), 2 deletions(-) |
| |
| diff --git a/drivers/hwmon/f71882fg.c b/drivers/hwmon/f71882fg.c |
| index 4dec793fd07d..94b35723ee7a 100644 |
| --- a/drivers/hwmon/f71882fg.c |
| +++ b/drivers/hwmon/f71882fg.c |
| @@ -1577,8 +1577,9 @@ 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); |
| } |
| -- |
| 2.35.1 |
| |
