Updating the tilcdc DRM driver code to calculate the LCD controller
pixel clock more accurately. Based on a suggested implementation by
Tomi Valkeinen.

The current code does not work correctly and produces wrong results
with many requested clock rates. It also oddly uses two different
clocks, a display pll clock and a divider clock (child of display
pll), instead of just using the clock coming to the lcdc.

This patch removes the use of the display pll clock, and rewrites the
code to calculate the clock rates. The idea is simply to request a
clock rate of pixelclock*2, as the LCD controller has an internal
divider which we set to 2.
Signed-off-by: NDarren Etheridge <detheridge@ti.com>
[Rewrapped description]
Signed-off-by: NJyri Sarha <jsarha@ti.com>
Reviewed-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

v2: Fixup misplaced hunks.

Cc: Rob Clark <robdclark@gmail.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-13-git-send-email-daniel.vetter@ffwll.ch

Add support for an external compontised DRM encoder. The external
encoder can be connected to tilcdc trough device tree graph binding.
The binding document for tilcdc has been updated. The current
implementation supports only tda998x encoder.

To be able to filter out the unsupported video modes the tilcdc driver
needs to hijack the external connectors helper functions. The tilcdc
installes new helper functions that are otherwise identical to
orignals, but the mode_valid() call-back check the mode first localy,
before calling the original call-back. The tilcdc dirver restores the
original helper functions before it is unbound from the external
device.

I got the idea and some lines of code from Jean-Francois Moine's
"drm/tilcdc: Change the interface with the tda998x driver"-patch.
Signed-off-by: NJyri Sarha <jsarha@ti.com>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

Remove tilcdc slave support for tda998x driver. The tilcdc slave
support would conflicts with componentized use of tda998x.
Signed-off-by: NJyri Sarha <jsarha@ti.com>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

The TI tilcdc driver is designed with a notion of submodules. Currently,
at unload time, these submodules are iterated and destroyed.

Now that the tilcdc remove order is fixed, this can be handled perfectly
by the kernel using the device infrastructure, since each submodule
is a kernel driver itself, and they are only destroy()'ed at unload
time. Therefore we move the destroy() functionality to each submodule's
remove().

Also, remove some checks in the unloading process since the new code
guarantees the resources are allocated and need a release.
Signed-off-by: NGuido Martínez <guido@vanguardiasur.com.ar>
Tested-by: NDarren Etheridge <detheridge@ti.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

In certain senarios drm will initialize before i2c this means that i2c
slave devices like the nxp tda998x will fail to be probed.  This patch
detects this condition then defers the probe of the slave device and
the tilcdc main driver.
Signed-off-by: NDarren Etheridge <detheridge@ti.com>
Acked-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Adding support for max-pixelclock and max-width device tree
entries. As some devices that use the tilcdc hardware module
have restrictions on the allowed/tested values.  Also update DT
bindings document to reflect new parameters.
Signed-off-by: NDarren Etheridge <detheridge@ti.com>
Acked-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The preferred_bpp value in currently hard-coded to 16.
This causes color corruption on the am335x-evm lcd panel which
requires 32 bpp instead. This changes attempts to use the configured
bpp value from the DT or built-in panel-info struct.
Signed-off-by: NBenoit Parrot <bparrot@ti.com>
Acked-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

A simple DRM/KMS driver for the TI LCD Controller found in various
smaller TI parts (AM33xx, OMAPL138, etc).  This driver uses the
CMA helpers.  Currently only the TFP410 DVI encoder is supported
(tested with beaglebone + DVI cape).  There are also various LCD
displays, for which support can be added (as I get hw to test on),
and an external i2c HDMI encoder found on some boards.

The display controller supports a single CRTC.  And the encoder+
connector are split out into sub-devices.  Depending on which LCD
or external encoder is actually present, the appropriate output
module(s) will be loaded.

v1: original
v2: fix fb refcnting and few other cleanups
v3: get +/- vsync/hsync from timings rather than panel-info, add
    option DT max-bandwidth field so driver doesn't attempt to
    pick a display mode with too high memory bandwidth, and other
    small cleanups
v4: remove some unneeded stuff from panel-info struct, properly
    set high bits for hfp/hsw/hbp for rev 2, add DT bindings docs
Signed-off-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: NKoen Kooi <koen@dominion.thruhere.net>