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

    commit 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.

Fixes: e97a45f1b460 ("hwmon: (lm75) Add OF device ID table")
Signed-off-by: Matwey V. Kornilov <mat...@sai.msu.ru>
---
 drivers/hwmon/lm75.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index e447febd121a..130ad5042107 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -561,9 +561,15 @@ static int lm75_probe(struct i2c_client *client)
        int status, err;
        enum lm75_type kind;
 
-       if (client->dev.of_node)
-               kind = (enum lm75_type)of_device_get_match_data(&client->dev);
-       else
+       if (dev->of_node) {
+               const struct of_device_id *match =
+                       of_match_device(dev->driver->of_match_table, dev);
+
+               if (!match)
+                       return -ENODEV;
+
+               kind = (enum lm75_type)(match->data);
+       } else
                kind = i2c_match_id(lm75_ids, client)->driver_data;
 
        if (!i2c_check_functionality(client->adapter,
-- 
2.26.2

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