Assert the DSI controller's reset when the driver is unloaded to reduce
power consumption and to put the controller into a known state for
subsequent driver reloads.
Signed-off-by: NThierry Reding <treding@nvidia.com>

When disabling the DSI controller, the code wasn't really doing what it
was supposed to.
Signed-off-by: NThierry Reding <treding@nvidia.com>

To prevent the enable or disable operations to potentially be run
multiple times, add guards to return early when the output is already
in the targetted state.
Signed-off-by: NThierry Reding <treding@nvidia.com>

The packet sequencer needs to be programmed depending on the video mode
of the attached peripheral. Add support for non-burst video modes with
sync events (as opposed to sync pulses) and select either sequence
depending on the video mode.
Signed-off-by: NThierry Reding <treding@nvidia.com>

The DSI controllers are powered by a (typically 1.2V) regulator. Usually
this is always on, so there was no need to support enabling or disabling
it thus far. But in order not to consume any power when DSI is inactive,
give the driver a chance to enable or disable the supply as needed.
Signed-off-by: NThierry Reding <treding@nvidia.com>

A bunch of registers are initialized to 0 upon during driver probe. It
turns out that none of these are actually needed, so they can simply be
dropped.
Signed-off-by: NThierry Reding <treding@nvidia.com>

The pixel format enumeration values used by the Tegra DSI controller
don't match those defined by the DSI framework. Make sure to convert
them to the internal format before writing it to the register.
Signed-off-by: NThierry Reding <treding@nvidia.com>

The majority of the code in this driver is licensed under the GPL v2, so
relicense the rest under GPL v2 as well for consistency.
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>

Some of the code in the CRTC's mode setting code is specific to the RGB
output or needs to be called slightly differently depending on the type
of output. Push that code down into the output drivers.
Signed-off-by: NThierry Reding <treding@nvidia.com>

In case of error, the devm_ioremap_resource() function returns ERR_PTR()
and never NULL. The NULL test in the return value check should therefore
be replaced with IS_ERR().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NThierry Reding <treding@nvidia.com>

This commit adds support for both DSI outputs found on Tegra. Only very
minimal functionality is implemented, so advanced features like ganged
mode won't work.

Due to the lack of other test hardware, some sections of the driver are
hardcoded to work with Dalmore.
Signed-off-by: NThierry Reding <treding@nvidia.com>