0560054da5
For the YUV conversion to work properly, ->x_scaling[1] should never
be set to VC4_SCALING_NONE, but vc4_get_scaling_mode() might return
VC4_SCALING_NONE if the horizontal scaling ratio exactly matches the
horizontal subsampling factor. Add a test to turn VC4_SCALING_NONE
into VC4_SCALING_PPF when that happens.
The old ->x_scaling[0] adjustment is dropped as I couldn't find any
mention to this constraint in the spec and it's proven to be
unnecessary (I tested various multi-planar YUV formats with scaling
disabled, and all of them worked fine without this adjustment).
Fixes: fc04023fafec ("drm/vc4: Add support for YUV planes.")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181109102633.32603-1-boris.brezillon@bootlin.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.
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.