b2644494a4
ADT7461 and TMP451 temperature sensors support extended temperature ranges. If standard temperature range is selected, the temperature range is unsigned and limited to 0 .. 127 degrees C. For TMP461, the standard temperature range is -128000 ... 127000 degrees C. Distinguish between the two chips by introducing a feature flag indicating if the standard temperature range is signed or unsigned. Use the same flag for MAX6646/ MAX6647 as well since those chips also support unsigned temperatures. Note that while the datasheet for ADT7461 suggests that the default temperature range is unsigned, tests with a real chip suggest that this is not the case: If the temperature offset is set to a value << 0, the temperature register does report negative values. Tests with real chips show that MAX6680/MAX6681 and SA56004 report temperatures of 128 degrees C and higher as negative temperatures. Add respective comments to the code. Also use clamp_val() and DIV_ROUND_CLOSEST where appropriate in calculations. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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.