David Lechner
2f176c0ec9
[ Upstream commite2c68cea43] Fix several issues with division of negative numbers in the tmp513 driver. The docs on the DIV_ROUND_CLOSEST macro explain that dividing a negative value by an unsigned type is undefined behavior. The driver was doing this in several places, i.e. data->shunt_uohms has type of u32. The actual "undefined" behavior is that it converts both values to unsigned before doing the division, for example: int ret = DIV_ROUND_CLOSEST(-100, 3U); results in ret == 1431655732 instead of -33. Furthermore the MILLI macro has a type of unsigned long. Multiplying a signed long by an unsigned long results in an unsigned long. So, we need to cast both MILLI and data data->shunt_uohms to long when using the DIV_ROUND_CLOSEST macro. Fixes:f07f9d2467("hwmon: (tmp513) Use SI constants from units.h") Fixes:59dfa75e5d("hwmon: Add driver for Texas Instruments TMP512/513 sensor chips.") Signed-off-by: David Lechner <dlechner@baylibre.com> Link: https://lore.kernel.org/r/20250114-fix-si-prefix-macro-sign-bugs-v1-1-696fd8d10f00@baylibre.com [groeck: Drop some continuation lines] Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.