patch "iio: ad7292: Prevent regulator double disable" added to char-misc-linus

patch "iio: ad7292: Prevent regulator double disable" added to char-misc-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: ad7292: Prevent regulator double disable

to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From 22b4277641c6823ec03d5b1cd82628e5e53e75b7 Mon Sep 17 00:00:00 2001
From: Matti Vaittinen <mazziesaccount@gmail.com>
Date: Fri, 19 Aug 2022 11:51:07 +0300
Subject: iio: ad7292: Prevent regulator double disable

The ad7292 tries to add an devm_action for disabling a regulator at
device detach using devm_add_action_or_reset(). The
devm_add_action_or_reset() does call the release function should adding
action fail. The driver inspects the value returned by
devm_add_action_or_reset() and manually calls regulator_disable() if
adding the action has failed. This leads to double disable and messes
the enable count for regulator.

Do not manually call disable if devm_add_action_or_reset() fails.

Fixes: 506d2e317a0a ("iio: adc: Add driver support for AD7292")
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Tested-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Link: https://lore.kernel.org/r/Yv9O+9sxU7gAv3vM@fedora
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/ad7292.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ad7292.c b/drivers/iio/adc/ad7292.c
index 92c68d467c50..a2f9fda25ff3 100644
--- a/drivers/iio/adc/ad7292.c
+++ b/drivers/iio/adc/ad7292.c
@@ -287,10 +287,8 @@ static int ad7292_probe(struct spi_device *spi)
 
 		ret = devm_add_action_or_reset(&spi->dev,
 					       ad7292_regulator_disable, st);
-		if (ret) {
-			regulator_disable(st->reg);
+		if (ret)
 			return ret;
-		}
 
 		ret = regulator_get_voltage(st->reg);
 		if (ret < 0)
-- 
2.37.2