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From 9354c224c9b4f55847a0de3e968cba2ebf15af3b Mon Sep 17 00:00:00 2001
From: Dmitry Rokosov <DDRokosov@sberdevices.ru>
Date: Tue, 24 May 2022 18:14:43 +0000
Subject: [PATCH] iio:accel:mxc4005: rearrange iio trigger get and register
Git-commit: 9354c224c9b4f55847a0de3e968cba2ebf15af3b
Patch-mainline: v5.19-rc4
References: git-fixes

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
callback or "delete module" path) will dereference "default" module
refcnt, which is incorrect behaviour.

Fixes: 47196620c82f ("iio: mxc4005: add data ready trigger for mxc4005")
Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220524181150.9240-4-ddrokosov@sberdevices.ru
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/iio/accel/mxc4005.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/mxc4005.c b/drivers/iio/accel/mxc4005.c
index b3afbf064915..df600d2917c0 100644
--- a/drivers/iio/accel/mxc4005.c
+++ b/drivers/iio/accel/mxc4005.c
@@ -456,8 +456,6 @@ static int mxc4005_probe(struct i2c_client *client,
 
 		data->dready_trig->ops = &mxc4005_trigger_ops;
 		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
-		indio_dev->trig = data->dready_trig;
-		iio_trigger_get(indio_dev->trig);
 		ret = devm_iio_trigger_register(&client->dev,
 						data->dready_trig);
 		if (ret) {
@@ -465,6 +463,8 @@ static int mxc4005_probe(struct i2c_client *client,
 				"failed to register trigger\n");
 			return ret;
 		}
+
+		indio_dev->trig = iio_trigger_get(data->dready_trig);
 	}
 
 	return devm_iio_device_register(&client->dev, indio_dev);
-- 
2.35.3