iio: adc: ad7923: Fix undersized rx buffer.

BugLink: https://bugs.launchpad.net/bugs/1931896
commit 01fcf129f61b26d5b3d2d8afb03e770dee271bc8 upstream.

Fixes tag is where the max channels became 8, but timestamp space was missing
before that.

Fixes: 851644a60d20 ("iio: adc: ad7923: Add support for the ad7908/ad7918/ad7928")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Daniel Junho <djunho@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210501165314.511954-3-jic23@kernel.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/drivers/iio/adc/ad7923.c b/drivers/iio/adc/ad7923.c
index a2cc966580540734e15a7685b046dce8e2f1503b..8c1e866f72e85971f79fad6771106801ce0bef91 100644 (file)
--- a/drivers/iio/adc/ad7923.c
+++ b/drivers/iio/adc/ad7923.c
@@ -59,8 +59,10 @@ struct ad7923_state {
        /*
         * DMA (thus cache coherency maintenance) requires the
         * transfer buffers to live in their own cache lines.
+        * Ensure rx_buf can be directly used in iio_push_to_buffers_with_timetamp
+        * Length = 8 channels + 4 extra for 8 byte timestamp
         */
-       __be16                          rx_buf[4] ____cacheline_aligned;
+       __be16                          rx_buf[12] ____cacheline_aligned;
        __be16                          tx_buf[4];
 };