João Paulo Gonçalves
90cf254f88
Add support for using the AMC6821 as a cooling device. The AMC6821 registers with the thermal framework only if the `cooling-levels` property is present in the fan device tree child node. If this property is present, the driver assumes the fan will operate in open-loop, and the kernel will control it directly. In this case, the driver will change the AMC6821 mode to manual (software DCY) and set the initial PWM duty cycle to the maximum fan cooling state level as defined in the DT. It is worth mentioning that the cooling device is registered on the child fan node, not on the fan controller node. Existing behavior is unchanged, so the AMC6821 can still be used without the thermal framework (hwmon only). Signed-off-by: João Paulo Gonçalves <joao.goncalves@toradex.com> Link: https://lore.kernel.org/r/20250613-b4-amc6821-cooling-device-support-v4-3-a8fc063c55de@toradex.com [groeck: Reduced line length when registering thermal device] 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.