mirror of
https://github.com/brain-hackers/linux-brain.git
synced 2024-06-09 23:36:23 +09:00
iio: iio-utils: Fix possible incorrect mask calculation
[ Upstream commit208a68c839
] 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>
This commit is contained in:
parent
fc9c15c4e3
commit
b150423e0d
|
@ -159,9 +159,9 @@ int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used,
|
|||
*be = (endianchar == 'b');
|
||||
*bytes = padint / 8;
|
||||
if (*bits_used == 64)
|
||||
*mask = ~0;
|
||||
*mask = ~(0ULL);
|
||||
else
|
||||
*mask = (1ULL << *bits_used) - 1;
|
||||
*mask = (1ULL << *bits_used) - 1ULL;
|
||||
|
||||
*is_signed = (signchar == 's');
|
||||
if (fclose(sysfsfp)) {
|
||||
|
|
Loading…
Reference in New Issue
Block a user