Linux uses get_modes() to fetch all available panel modes from the
driver. This is also used to fetch the modes from Linux's simple panel
implementation where a list of drm_display_mode structs is used to
define the different possible panels.

To make our work easier, create a compatible way of fetching and
defining these modes in u-boot. get_modes() fetches the available modes
from the panel driver. The get_display_timing() call maps the
drm_display_mode properties to the display_timing struct. This call now
uses whatever panel operation is available, get_display_timing() or
get_modes().

Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Markus Schneider-Pargmann (TI.com) <msp@baylibre.com>

For completeness add it.

Signed-off-by: Markus Schneider-Pargmann (TI.com) <msp@baylibre.com>

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

At present the panel can be turned on but not off, and the brightness
cannot be controlled at run-time. Add a new API function to both the panel
and backlight uclasses to handle this. Enhance the PWM backlight driver
to deal with custom levels properly and allow the backlight to be turned
on and off.

Update the test to cover thes new features.

Signed-off-by: Simon Glass <sjg@chromium.org>

Get timings from panel instead of read device tree.

Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

LCD panels can usefully be modelled as their own uclass. They can be probed
(which powers them up ready for use). If they have a backlight, this can be
enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>