Some clocks and resets supposed to drive the LVDS logic in the display
engine have been overlooked when the driver was first introduced.

Add those additional resources to the binding, and we'll deal with the ABI
stability in the code.
Reviewed-by: NChen-Yu Tsai <wens@csie.org>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ddbde28fe2e4f21412974e4c69fbfe1c5ff9383f.1513854122.git-series.maxime.ripard@free-electrons.com

Improve the binding example by removing all the leading zeros to fix the
following dtc warnings:

Warning (unit_address_format): Node /XXX unit name should not have leading 0s

Converted using the following command:

perl -p -i -e 's/\@0+([0-9a-f])/\@$1/g' `find ./Documentation/devicetree/bindings "*.txt"`

Some unnecessary changes were manually fixed.
Signed-off-by: NMarco Franchi <marco.franchi@nxp.com>
Signed-off-by: NRob Herring <robh@kernel.org>

The A20 display pipeline has 2 frontends, 2 backends, and 2 TCONs.
This patch adds support (or a compatible string in the frontend's
case) for these components.

The TCONs support directly outputting to CPU/RGB/LVDS LCD panels,
or it can output to HDMI via an on-chip HDMI controller, or
CVBS/YPbPr/VGA signals via on-chip TV encoders. These additional
encoders are not covered in this patch.
Signed-off-by: NJonathan Liu <net147@gmail.com>
[wens@csie.org: Expand commit message]
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171017121807.2994-6-wens@csie.org

The A10 display pipeline has 2 frontends, 2 backends, and 2 TCONs.
This patch adds support (or a compatible string in the frontend's
case) for these components.

The TCONs support directly outputting to CPU/RGB/LVDS LCD panels,
or it can output to HDMI via an on-chip HDMI controller, or
CVBS/YPbPr/VGA signals via on-chip TV encoders. These additional
encoders are not covered in this patch.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171017121807.2994-5-wens@csie.org

The HDMI controller in the A10 SoC is the same as the one currently
supported in the A10s. It has slightly different setup parameters.
Since these parameters are not thoroughly understood, we add support
for this variant by copying these parameters verbatim.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171017121807.2994-4-wens@csie.org

The A10 has two TCONs that are similar to the ones found on other SoCs.
Like the A31, TCON0 has a register used to mux the TCON outputs to the
downstream encoders. The bit fields are slightly different.
Signed-off-by: NJonathan Liu <net147@gmail.com>
[wens@csie.org: Reworked for A10 and fixed up commit message]
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171017121807.2994-3-wens@csie.org

The HDMI controller in the A31 SoC is slightly different from the
earlier version. In addition to the TMDS clock and DDC controls,
this version now takes a second DDC clock input.

Add a compatible string for it, and add the DDC clock input to the
list of clocks required.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010032008.682-7-wens@csie.org

Pretty much any node can have a status property, so it doesn't need to
be in examples.

Converted with the following command and removed examples with SoC and
board specific splits:

git grep -l -E 'status.*=.*' Documentation/devicetree/ | xargs sed -i -E '/\sstatus.*=.*"(disabled|ok|okay)/d'
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NRob Herring <robh@kernel.org>

The explanation for the endpoint ID numbering scheme is convoluted
and hard to understand.

This patch aims to improve the readability of it by combining the
existing two paragraphs, while also providing a diagram example,
and how endpoints should be numbered based on that example.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The A10s has a slightly different display pipeline than the A13, with an
HDMI controller.

Add a compatible for it.
Reviewed-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The Allwinner Timings Controller has two, mutually exclusive, channels.
When the binding has been introduced, it was assumed that there would be
only a single user per channel in the system.

While this is likely for the channel 0 which only connects to LCD displays,
it turns out that the channel 1 can be connected to multiple controllers in
the SoC (HDMI and TV encoders for example). And while the simultaneous use
of HDMI and TV outputs cannot be achieved, switching from one to the other
at runtime definitely sounds plausible.

Add an extra property, allwinner,tcon-channel, to specify for a given
endpoint which TCON channel it is connected to, while falling back to the
previous mechanism if that property is missing.
Acked-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

One of the possible output of the display pipeline, on the SoCs that have
it, is the HDMI controller.

Add a binding for it.
Acked-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

Allwinner V3s SoC have a display engine which have a different pipeline
with older SoCs.

Add document for it (new compatibles and the new "mixer" part).
Signed-off-by: NIcenowy Zheng <icenowy@aosc.io>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The Allwinner display pipeline contains many hardware components, some
of which can consume data from one of multiple upstream components.
The numbering scheme of these components must be encoded into the device
tree so the driver can figure out which component out of two or more of
the same type it is supposed to use or program.

This patch adds the constraint that local endpoint IDs must be the index
or number of the remote endpoint's hardware block, for all components
in the display pipeline up to the TCONs.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The display backend has an interrupt line. Add it to the device tree
binding.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The A31's display pipeline has 2 frontends, 2 backends, and 2 TCONs. It
also has new display enhancement blocks, such as the DRC (Dynamic Range
Controller), the DEU (Display Enhancement Unit), and the CMU (Color
Management Unit). It supports HDMI, MIPI DSI, and 2 LCD/LVDS channels.

The A31s display pipeline is almost the same, just without MIPI DSI.
Only the TCON seems to be different, due to the missing mux for MIPI
DSI.

Add compatible strings for both of them.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The A31 TCON has mux controls for how TCON outputs are routed to the
HDMI and MIPI DSI blocks.

Since the A31s does not have MIPI DSI, it only has a mux for the HDMI
controller input.

This patch only adds support for the compatible strings. Actual support
for the mux controls should be added with HDMI and MIPI DSI support.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

The A31 and A31s also have the DRC as part of the display pipeline.
As we know virtually nothing about them, just add compatible strings
for both SoCs to the stub driver.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime 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: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NChen-Yu Tsai <wens@csie.org>
Acked-by: NPeter Korsgaard <peter@korsgaard.com>

The A33 has an block called SAT that is part of the backend that needs to
be clocked and out of reset to be able for the backend to operate properly.

Extend the binding to have the SAT resources listed, and claim them when
the backend probes.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NChen-Yu Tsai <wens@csie.org>

The A33 has a significantly different pipeline, with components that differ
too.

Make sure we had compatible for them.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NChen-Yu Tsai <wens@csie.org>

The display pipeline of the Allwinner A10 is involving several loosely
coupled components.

Add a documentation for the bindings.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>