[PATCH] hwmon: lm75: Use zero lm75_type for lm75

From: Matwey V. Kornilov
Date: Sat Jan 30 2021 - 05:16:41 EST


There is a logical flaw in lm75_probe() function introduced in

e97a45f1b460 ("hwmon: (lm75) Add OF device ID table")

Note, that of_device_get_match_data() returns NULL when no match
found. This is the case when OF node exists but has unknown
compatible line, while the module is still loaded via i2c
detection.

arch/powerpc/boot/dts/fsl/p2041rdb.dts:

lm75b@48 {
compatible = "nxp,lm75a";
reg = <0x48>;
};

In this case, the sensor is mistakenly considered as ADT75 variant.
The simplest way to handle this issue is to make the LM75 code
zero.

Fixes: e97a45f1b460 ("hwmon: (lm75) Add OF device ID table")
Signed-off-by: Matwey V. Kornilov <matwey@xxxxxxxxxx>
---
drivers/hwmon/lm75.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index e447febd121a..3aa7f9454f57 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -25,12 +25,12 @@
*/

enum lm75_type { /* keep sorted in alphabetical order */
+ lm75 = 0, /* except of lm75 which is default fallback */
adt75,
ds1775,
ds75,
ds7505,
g751,
- lm75,
lm75a,
lm75b,
max6625,
--
2.26.2