[PATCH v1 1/5] iio:accel:bma180: rearrange iio trigger get and register

Dmitry Rokosov posted 5 patches 3 years, 8 months ago
There is a newer version of this series
[PATCH v1 1/5] iio:accel:bma180: rearrange iio trigger get and register
Posted by Dmitry Rokosov 3 years, 8 months ago
IIO trigger interface function iio_trigger_get() should be called after
iio_trigger_register() (or its devm analogue) strictly, because of
iio_trigger_get() acquires module refcnt based on the trigger->owner
pointer, which is initialized inside iio_trigger_register() to
THIS_MODULE.
If this call order is wrong, the next iio_trigger_put() (from sysfs
callbacks or rmmod) will derefence "default" module refcnt, which is
completely incorrect.

Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
---
 drivers/iio/accel/bma180.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/bma180.c b/drivers/iio/accel/bma180.c
index d8a454c266d5..5d0bd0fc3018 100644
--- a/drivers/iio/accel/bma180.c
+++ b/drivers/iio/accel/bma180.c
@@ -1006,11 +1006,12 @@ static int bma180_probe(struct i2c_client *client,
 
 		data->trig->ops = &bma180_trigger_ops;
 		iio_trigger_set_drvdata(data->trig, indio_dev);
-		indio_dev->trig = iio_trigger_get(data->trig);
 
 		ret = iio_trigger_register(data->trig);
 		if (ret)
 			goto err_trigger_free;
+
+		indio_dev->trig = iio_trigger_get(data->trig);
 	}
 
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
-- 
2.36.0