The tcon provides part of the functionality of the crtc, and also
provides the device node for the output port of the crtc. To be able
to use drm_of_find_possible_crtcs(), all crtc must be initialized before
any downstream encoders. The other part of the crtc is the display
backend.
The Rockchip DRM driver does this by first binding all vops, which is
their crtc, and this step also creates the crtc objects. Then all
remaining hardware components are bound. With the Allwinner display
pipeline, we have multiple components comprising the crtc, and varying
depths of the display pipeline. Since components are added with a depth
first search of the of_graph, we can initialize the crtc object within
the tcon bind function. Since the backend precedes the tcon, and the
backends cannot be muxed or switched around, we can be sure that the
associated backend is already initialized.
This patch also moves the crtc pointer from the main drm_device data to
the tcon device data. Besides the crtc callbacks, the crtc structure is
only used within the tcon driver to signal vblank events from its
interrupt handler.
As the crtc and layer bits are now called from the tcon bits, we must
move them from the sun4i-drm module to the sun4i-tcon module to avoid
circular dependencies between the two modules. This is because sun4i-drm
also calls into sun4i-tcon.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The A33 pipeline also has a component called DRC. Even though its exact
features and programming model is not known (or documented), it needs to
be clocked for the pipeline to carry the video signal all the way.
Add a minimal driver for it that just claim the needed resources for the
pipeline to operate properly.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Some Allwinner SoCs have an IP called the TV encoder that is used to output
composite and VGA signals. In such a case, we need to use the second TCON
channel.
Add support for that TV encoder.
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
One of the A10 display pipeline possible output is an RGB interface to
drive LCD panels directly. This is done through the first channel of the
TCON that will output our video signals directly.
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The Allwinner A10 and subsequent SoCs share the same display pipeline, with
variations in the number of controllers (1 or 2), or the presence or not of
some output (HDMI, TV, VGA) or not.
Add a driver with a limited set of features for now, and we will hopefully
support all of them eventually
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
