iio: adc: hx711: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

BugLink: https://bugs.launchpad.net/bugs/1938199
[ Upstream commit afe2a789fbf7acd1a05407fc7839cc08d23825e3 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of this function.

Fixes: d3bf60450d47 ("iio: hx711: add triggered buffer support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andreas Klinger <ak@it-klinger.de>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210613152301.571002-3-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
index 62e6c8badd22a8d645c9edb1e0d10784157a5b61..a3265166fd83552e8aed395b8c7ee02a77bdfb6c 100644 (file)
--- a/drivers/iio/adc/hx711.c
+++ b/drivers/iio/adc/hx711.c
@@ -85,9 +85,9 @@ struct hx711_data {
        struct mutex            lock;
        /*
         * triggered buffer
-        * 2x32-bit channel + 64-bit timestamp
+        * 2x32-bit channel + 64-bit naturally aligned timestamp
         */
-       u32                     buffer[4];
+       u32                     buffer[4] __aligned(8);
        /*
         * delay after a rising edge on SCK until the data is ready DOUT
         * this is dependent on the hx711 where the datasheet tells a