[PATCH AUTOSEL 5.6 06/38] hwmon: (drivetemp) Return -ENODATA for invalid temperatures

Sasha Levin
2020-04-24T12:22:50Z

From: Guenter Roeck <linux@roeck-us.net>

[ Upstream commit ed08ebb7124e90a99420bb913d602907d377d03d ]

Holger Hoffstätte observed that Samsung 850 Pro may return invalid
temperatures for a short period of time after resume. Return -ENODATA
to userspace if this is observed.

Fixes: 5b46903d8bf3 ("hwmon: Driver for disk and solid state drives with temperature sensors")
Reported-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Cc: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/hwmon/drivetemp.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/hwmon/drivetemp.c b/drivers/hwmon/drivetemp.c
index 370d0c74eb012..9179460c2d9d5 100644
--- a/drivers/hwmon/drivetemp.c
+++ b/drivers/hwmon/drivetemp.c
@@ -264,12 +264,18 @@ static int drivetemp_get_scttemp(struct drivetemp_data *st, u32 attr, long *val)
return err;
switch (attr) {
case hwmon_temp_input:
+ if (!temp_is_valid(buf[SCT_STATUS_TEMP]))
+ return -ENODATA;
*val = temp_from_sct(buf[SCT_STATUS_TEMP]);
break;
case hwmon_temp_lowest:
+ if (!temp_is_valid(buf[SCT_STATUS_TEMP_LOWEST]))
+ return -ENODATA;
*val = temp_from_sct(buf[SCT_STATUS_TEMP_LOWEST]);
break;
case hwmon_temp_highest:
+ if (!temp_is_valid(buf[SCT_STATUS_TEMP_HIGHEST]))
+ return -ENODATA;
*val = temp_from_sct(buf[SCT_STATUS_TEMP_HIGHEST]);
break;
default:
--
2.20.1