From d710359c0b445e8c03e24f19ae2fb79ce7282260 Mon Sep 17 00:00:00 2001
From: Dmitry Rokosov <DDRokosov@sberdevices.ru>
Date: Tue, 24 May 2022 18:14:45 +0000
Subject: [PATCH] iio:chemical:ccs811: rearrange iio trigger get and register
Git-commit: d710359c0b445e8c03e24f19ae2fb79ce7282260
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: f1f065d7ac30 ("iio: chemical: ccs811: Add support for data ready trigger")
Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220524181150.9240-5-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/chemical/ccs811.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c
index 847194fa1e46..80ef1aa9aae3 100644
--- a/drivers/iio/chemical/ccs811.c
+++ b/drivers/iio/chemical/ccs811.c
@@ -499,11 +499,11 @@ static int ccs811_probe(struct i2c_client *client,
 
 		data->drdy_trig->ops = &ccs811_trigger_ops;
 		iio_trigger_set_drvdata(data->drdy_trig, indio_dev);
-		indio_dev->trig = data->drdy_trig;
-		iio_trigger_get(indio_dev->trig);
 		ret = iio_trigger_register(data->drdy_trig);
 		if (ret)
 			goto err_poweroff;
+
+		indio_dev->trig = iio_trigger_get(data->drdy_trig);
 	}
 
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
-- 
2.35.3