cb09e99b9a
[ Upstream commit 49ad712afa88c502831d37f7089d98eac441fb80 ] The Image Signal Processor found on Cherry Trail devices is brought up in D0 state on devices which have camera sensors attached to it. The ISP will not enter D3 state again without some massaging of its registers beforehand and the ISP not being in D3 state blocks the SoC from entering S0ix modes. There was a driver for the ISP in drivers/staging but that got removed again because it never worked. It does not seem likely that a real driver for the ISP will be added to the mainline kernel anytime soon. This commit adds a dummy driver which contains the necessary magic from the staging driver to powerdown the ISP, so that Cherry Trail devices where the ISP is used will properly use S0ix modes when suspended. Together with other recent S0ix related fixes this allows S0ix modes to be entered on e.g. a Chuwi Hi8 Pro and a HP x2 210. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=196915 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> 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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.