drm/tilcdc: adding some more devicetree config

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: Darren Etheridge <detheridge@ti.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt b/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
index e5f1301..fff10da 100644
--- a/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
+++ b/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
@@ -10,6 +10,14 @@
    services interrupts for this device.
  - ti,hwmods: Name of the hwmod associated to the LCDC
 
+Optional properties:
+ - max-bandwidth: The maximum pixels per second that the memory
+   interface / lcd controller combination can sustain
+ - max-width: The maximum horizontal pixel width supported by
+   the lcd controller.
+ - max-pixelclock: The maximum pixel clock that can be supported
+   by the lcd controller in KHz.
+
 Example:
 
 	fb: fb@4830e000 {