The drivers current default configuration drives the pixel data
on rising edge of the pixel clock. However, most display sample
data on rising edge... This leads to color shift artefacts visible
especially at edges.

This patch changes the relevant defines to be useful and actually
set the bits, and changes pixel clock polarity to drive the pixel
data on falling edge by default. The patch also adds an explicit
pixel clock polarity flag to the display introduced with the driver
(NEC WQVGA "nec,nl4827hc19-05b") using the new bus_flags field to
retain the initial behavior.
Signed-off-by: NStefan Agner <stefan@agner.ch>

Add driver for the TCON (timing controller) module. The TCON module
is a separate module attached after the DCU (display controller
unit). Each DCU instance has its own, directly connected TCON
instance. The DCU's RGB and timing signals are passing through
the TCON module. TCON can provide timing signals for raw TFT panels
or operate in a bypass mode which leaves all signals unaltered.

The driver currently only supports the bypass mode.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NStefan Agner <stefan@agner.ch>

The Vybrid DCU variant has two independent clock inputs, one
for the registers (IPG bus clock) and one for the pixel clock.
Support this distinction in the DCU DRM driver while staying
backward compatible for old device trees.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NStefan Agner <stefan@agner.ch>

Fix alpha blending by enabling alpha blending for the whole frame if
a color mode with alpha channel is selected (DRM_FORMAT_ARGB*). Also
support color modes without alpha channel (DRM_FORMAT_XRGB*) by just
not enabling alpha blending on layer level.
Signed-off-by: NStefan Agner <stefan@agner.ch>

This patch add support for Two Dimensional Animation and Compositing
Engine (2D-ACE) on the Freescale SoCs.

2D-ACE is a Freescale display controller. 2D-ACE describes
the functionality of the module extremely well its name is a value
that cannot be used as a token in programming languages.
Instead the valid token "DCU" is used to tag the register names and
function names.

The Display Controller Unit (DCU) module is a system master that
fetches graphics stored in internal or external memory and displays
them on a TFT LCD panel. A wide range of panel sizes is supported
and the timing of the interface signals is highly configurable.
Graphics are read directly from memory and then blended in real-time,
which allows for dynamic content creation with minimal CPU
intervention.

The features:
(1) Full RGB888 output to TFT LCD panel.
(2) Blending of each pixel using up to 4 source layers
dependent
on size of panel.
(3) Each graphic layer can be placed with one pixel resolution
in either axis.
(4) Each graphic layer support RGB565 and RGB888 direct colors
without alpha channel and BGRA8888 BGRA4444 ARGB1555 direct
colors
with an alpha channel and YUV422 format.
(5) Each graphic layer support alpha blending with 8-bit
resolution.
This is a simplified version, only one primary plane, one
framebuffer, one crtc, one connector and one encoder for TFT
LCD panel.
Signed-off-by: NAlison Wang <b18965@freescale.com>
Signed-off-by: NXiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: NJianwei Wang <jianwei.wang.chn@gmail.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>