Move enable/disable/suspend/resume from omap_dss_device to
omap_dss_driver.

This is part of a larger patch-set, which moves the control from omapdss
driver to the display driver.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

Move set/get_update_mode() from omap_dss_device to omap_dss_driver.

This is part of a larger patch-set, which moves the control from omapdss
driver to the display driver.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

Move enable/disable_channel() from omap_dss_device to overlay manager.

This is part of a larger patch-set, which moves the control from omapdss
driver to the display driver.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

dss_select_clk_source() was rather confusing. Selecting the source with
enums is much clearer.

The clk source selection is also stored into memory, so that we know what
is the selected source, even when clocks are off. This is important during
setup, as we need to what clocks to turn on before the clocks are turned
on.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

It looks like on OMAP3 some DSS pins need VDDS_DSI to function properly.

This has not been confirmed from TI, but looking at figure 15-1 "Display
subsystem highlight" from the TRM, some data pins come near the DSI and SDI
blocks. This is not very hard evidence, but the fact remains that with the
power on, pixels are ok, and with the power off, pixels are not ok.

It may also be that VDDS_SDI is needed to power some pins, but as normally
both VDDS_SDI and VDDS_DSI come from the same power source, this hasn't
been shown.

It seems that a single driver can only get a regulator once. This patch
solves it by getting all the required regulators in one place, and from
which the submodules then get the regulators they need.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

This implements MIPI DPI interface.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>