[PATCH v2] iio: adc: viperboard: Fix error handling in vprbrd_iio_read_raw
From: Salah Triki
Date: Thu May 07 2026 - 15:08:04 EST
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@xxxxxxxxx>
Reviewed-by: Joshua Crofts <joshua.crofts1@xxxxxxxxx>
Reviewed-by: Maxwell Doose <m32285159@xxxxxxxxx>
---
Changes in v2:
- Add "adc" to the patch title.
- Move dev_err() out of the mutex critical section.
- Include Reviewed-by tags from Joshua and Maxwell.
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..f7ce3effd730 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");
error = -EREMOTEIO;
+ mutex_unlock(&vb->lock);
+ dev_err(&iio_dev->dev, "usb send error on adc read\n");
+ goto error;
}
ret = usb_control_msg(vb->usb_dev,
--
2.43.0