8f4fd97df2
The default value of the maximum fan speed limit register is 0, essentially translating to an unlimited fan speed. When reading the limit, a value of 0 is reported in this case. However, writing a value of 0 results in writing a value of 0xffff into the register, which is inconsistent. To solve the problem, permit writing a limit of 0 for the maximim fan speed, effectively translating to "no limit". Write 0 into the register if a limit value of 0 is written. Otherwise limit the range to <1..6000000> and write 1..0xffff into the register. This ensures that reading and writing from and to a limit register return the same value while at the same time not changing reported values when reading the speed or limits. While at it, restrict fan limit writes to non-negative numbers; writing a negative limit does not make sense and should be reported instead of being corrected. Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de> 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 reStructuredText 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.