linux-brain/tools/iio
Bastien Nocera 44b2e647a5 iio: iio-utils: Fix possible incorrect mask calculation
[ Upstream commit 208a68c839 ]

On some machines, iio-sensor-proxy was returning all 0's for IIO sensor
values. It turns out that the bits_used for this sensor is 32, which makes
the mask calculation:

*mask = (1 << 32) - 1;

If the compiler interprets the 1 literals as 32-bit ints, it generates
undefined behavior depending on compiler version and optimization level.
On my system, it optimizes out the shift, so the mask value becomes

*mask = (1) - 1;

With a mask value of 0, iio-sensor-proxy will always return 0 for every axis.

Avoid incorrect 0 values caused by compiler optimization.

See original fix by Brett Dutro <brett.dutro@gmail.com> in
iio-sensor-proxy:
9615ceac7c

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31 07:28:53 +02:00
..
Build iio: tools: move to tools buildsystem 2017-08-09 14:29:36 +01:00
Makefile tools: fix cross-compile var clobbering 2019-01-13 10:01:02 +01:00
iio_event_monitor.c iio: Add channel for Gravity 2017-01-05 13:02:25 +00:00
iio_generic_buffer.c tools: iio: iio_generic_buffer: drop unneeded parentheses 2016-10-23 19:34:10 +01:00
iio_utils.c iio: iio-utils: Fix possible incorrect mask calculation 2019-07-31 07:28:53 +02:00
iio_utils.h iio: tools: generic_buffer: increase trigger length 2017-05-07 16:08:04 +01:00
lsiio.c tools: iio: lsiio: enumerate processed channels 2016-08-15 18:33:23 +01:00