patch "iio: adc: viperboard: Fix error handling in vprbrd_iio_read_raw" 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: viperboard: Fix error handling in vprbrd_iio_read_raw

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 422b5bbf333f75fb486855ad0eedc23cf21f3277 Mon Sep 17 00:00:00 2001
From: Salah Triki <salah.triki@gmail.com>
Date: Thu, 7 May 2026 20:07:51 +0100
Subject: iio: adc: viperboard: Fix error handling in vprbrd_iio_read_raw
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The driver proceeds to the reception phase even if the preceding
transmission fails.

This uses a goto error label for an early bail out and ensures the mutex is
properly unlocked in case of failure.

Fixes: ffd8a6e7a778 ("iio: adc: Add viperboard adc driver")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Reviewed-by: Maxwell Doose <m32285159@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/adc/viperboard_adc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/viperboard_adc.c b/drivers/iio/adc/viperboard_adc.c
index 9bb0b83c8f67..6efe1c618ef7 100644
--- a/drivers/iio/adc/viperboard_adc.c
+++ b/drivers/iio/adc/viperboard_adc.c
@@ -70,8 +70,10 @@ static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
 			VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
 			sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
 		if (ret != sizeof(struct vprbrd_adc_msg)) {
-			dev_err(&iio_dev->dev, "usb send error on adc read\n");
+			mutex_unlock(&vb->lock);
 			error = -EREMOTEIO;
+			dev_err(&iio_dev->dev, "usb send error on adc read\n");
+			goto error;
 		}
 
 		ret = usb_control_msg(vb->usb_dev,
-- 
2.54.0