fd67e9c6ed
The Tegra DRM driver heavily relies on the implementations for runtime suspend/resume to be called at specific times. Unfortunately, there are some cases where that doesn't work. One example is if the user disables runtime PM for a given subdevice. Another example is that the PM core acquires a reference to runtime PM during system sleep, effectively preventing devices from going into low power modes. This is intentional to avoid nasty race conditions, but it also causes system sleep to not function properly on all Tegra systems. Fix this by not implementing runtime PM at all. Instead, a minimal, reference-counted suspend/resume infrastructure is added to the host1x bus. This has the benefit that it can be used regardless of the system power state (or any transitions we might be in), or whether or not the user allows runtime PM. Atomic modesetting guarantees that these functions will end up being called at the right point in time, so the pitfalls for the more generic runtime PM do not apply here. Signed-off-by: Thierry Reding <treding@nvidia.com>
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.