[PATCH] iio: core: WARN in case sample bits do not fit storage bits

[Marek Vasut <marex@denx.de>]

Add runtime check to verify whether storagebits are at least as big
as shifted realbits. This should help spot broken drivers which may
set realbits + shift above storagebits.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Daniel Baluta <daniel.baluta@nxp.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/industrialio-buffer.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index b078eb2f3c9de..bac1e994e7bef 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -1629,6 +1629,11 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
 			if (channels[i].scan_index < 0)
 				continue;
 
+			/* Verify that sample bits fit into storage */
+			WARN_ON(channels[i].scan_type.storagebits <
+				channels[i].scan_type.realbits +
+				channels[i].scan_type.shift);
+
 			ret = iio_buffer_add_channel_sysfs(indio_dev, buffer,
 							 &channels[i]);
 			if (ret < 0)
-- 
2.35.1