From 4b1d074afbe33e4d7212bfa1b398323d280b3c5c Mon Sep 17 00:00:00 2001 From: Riwen Lu Date: Fri, 4 Jun 2021 11:09:59 +0800 Subject: [PATCH] hwmon: (scpi-hwmon) shows the negative temperature properly BugLink: https://bugs.launchpad.net/bugs/1936688 [ Upstream commit 78d13552346289bad4a9bf8eabb5eec5e5a321a5 ] The scpi hwmon shows the sub-zero temperature in an unsigned integer, which would confuse the users when the machine works in low temperature environment. This shows the sub-zero temperature in an signed value and users can get it properly from sensors. Signed-off-by: Riwen Lu Tested-by: Xin Chen Link: https://lore.kernel.org/r/20210604030959.736379-1-luriwen@kylinos.cn Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin Signed-off-by: Kamal Mostafa Signed-off-by: Stefan Bader --- drivers/hwmon/scpi-hwmon.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/hwmon/scpi-hwmon.c b/drivers/hwmon/scpi-hwmon.c index 25aac40f2764..919877970ae3 100644 --- a/drivers/hwmon/scpi-hwmon.c +++ b/drivers/hwmon/scpi-hwmon.c @@ -99,6 +99,15 @@ scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf) scpi_scale_reading(&value, sensor); + /* + * Temperature sensor values are treated as signed values based on + * observation even though that is not explicitly specified, and + * because an unsigned u64 temperature does not really make practical + * sense especially when the temperature is below zero degrees Celsius. + */ + if (sensor->info.class == TEMPERATURE) + return sprintf(buf, "%lld\n", (s64)value); + return sprintf(buf, "%llu\n", value); } -- 2.39.5