Searched hist:"67 e972130bb646e34ed96c21499c93d35bc74474" (Results 1 – 1 of 1) sorted by relevance
/openbmc/linux/drivers/iio/magnetometer/ |
H A D | yamaha-yas530.c | diff 67e972130bb646e34ed96c21499c93d35bc74474 Fri Nov 29 15:25:07 CST 2024 Jakob Hauser <jahau@rocketmail.com> iio: magnetometer: yas530: use signed integer type for clamp limits
[ Upstream commit f1ee5483e40881d8ad5a63aa148b753b5c6a839b ]
In the function yas537_measure() there is a clamp_val() with limits of -BIT(13) and BIT(13) - 1. The input clamp value h[] is of type s32. The BIT() is of type unsigned long integer due to its define in include/vdso/bits.h. The lower limit -BIT(13) is recognized as -8192 but expressed as an unsigned long integer. The size of an unsigned long integer differs between 32-bit and 64-bit architectures. Converting this to type s32 may lead to undesired behavior.
Additionally, in the calculation lines h[0], h[1] and h[2] the unsigned long integer divisor BIT(13) causes an unsigned division, shifting the left-hand side of the equation back and forth, possibly ending up in large positive values instead of negative values on 32-bit architectures.
To solve those two issues, declare a signed integer with a value of BIT(13).
There is another omission in the clamp line: clamp_val() returns a value and it's going nowhere here. Self-assign it to h[i] to make use of the clamp macro.
Finally, replace clamp_val() macro by clamp() because after changing the limits from type unsigned long integer to signed integer it's fine that way.
Link: https://lkml.kernel.org/r/11609b2243c295d65ab4d47e78c239d61ad6be75.1732914810.git.jahau@rocketmail.com Fixes: 65f79b501030 ("iio: magnetometer: yas530: Add YAS537 variant") Signed-off-by: Jakob Hauser <jahau@rocketmail.com>
Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202411230458.dhZwh3TT-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202411282222.oF0B4110-lkp@intel.com/ Reviewed-by: David Laight <david.laight@aculab.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
|