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(-)

--- a/drivers/iio/chemical/ccs811.c

+++ b/drivers/iio/chemical/ccs811.c

@@ -418,11 +418,11 @@ static int ccs811_probe(struct i2c_clien

 		data->drdy_trig->dev.parent = &client->dev;

 		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,