patch "iio: adc: ad7606: check for NULL before calling sw_mode_config()" added to char-misc-linus

[<gregkh@linuxfoundation.org>]

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

    iio: adc: ad7606: check for NULL before calling sw_mode_config()

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 5257d80e22bf27009d6742e4c174f42cfe54e425 Mon Sep 17 00:00:00 2001
From: David Lechner <dlechner@baylibre.com>
Date: Tue, 18 Mar 2025 17:52:09 -0500
Subject: iio: adc: ad7606: check for NULL before calling sw_mode_config()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Check that the sw_mode_config function pointer is not NULL before
calling it. Not all buses define this callback, which resulted in a NULL
pointer dereference.

Fixes: e571c1902116 ("iio: adc: ad7606: move scale_setup as function pointer on chip-info")
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20250318-iio-adc-ad7606-improvements-v2-1-4b605427774c@baylibre.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/ad7606.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
index 1a314fddd7eb..703556eb7257 100644
--- a/drivers/iio/adc/ad7606.c
+++ b/drivers/iio/adc/ad7606.c
@@ -1236,9 +1236,11 @@ static int ad7616_sw_mode_setup(struct iio_dev *indio_dev)
 	st->write_scale = ad7616_write_scale_sw;
 	st->write_os = &ad7616_write_os_sw;
 
-	ret = st->bops->sw_mode_config(indio_dev);
-	if (ret)
-		return ret;
+	if (st->bops->sw_mode_config) {
+		ret = st->bops->sw_mode_config(indio_dev);
+		if (ret)
+			return ret;
+	}
 
 	/* Activate Burst mode and SEQEN MODE */
 	return ad7606_write_mask(st, AD7616_CONFIGURATION_REGISTER,
@@ -1268,6 +1270,9 @@ static int ad7606b_sw_mode_setup(struct iio_dev *indio_dev)
 	st->write_scale = ad7606_write_scale_sw;
 	st->write_os = &ad7606_write_os_sw;
 
+	if (!st->bops->sw_mode_config)
+		return 0;
+
 	return st->bops->sw_mode_config(indio_dev);
 }
 
-- 
2.49.0