iio:accel:kxsd9 fix missing mutex unlock

commit 0ee005c7dc2803125275e24598f0fb37775a6af3 upstream.

This will leave a lock held after reading from the device, preventing
any further reads.

Signed-off-by: Frank Zago <frank@zago.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c
index 709c132..3427715 100644 (file)
--- a/drivers/iio/accel/kxsd9.c
+++ b/drivers/iio/accel/kxsd9.c
@@ -112,9 +112,10 @@ static int kxsd9_read(struct iio_dev *indio_dev, u8 address)
        mutex_lock(&st->buf_lock);
        st->tx[0] = KXSD9_READ(address);
        ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
-       if (ret)
-               return ret;
-       return (((u16)(st->rx[0])) << 8) | (st->rx[1] & 0xF0);
+       if (!ret)
+               ret = (((u16)(st->rx[0])) << 8) | (st->rx[1] & 0xF0);
+       mutex_unlock(&st->buf_lock);
+       return ret;
 }
 
 static IIO_CONST_ATTR(accel_scale_available,