dt-bindings: display: Start the info graphics with HS/VS change
authorMarek Vasut <marex@denx.de>
Tue, 21 Feb 2023 20:04:07 +0000 (21:04 +0100)
committerMarek Vasut <marex@denx.de>
Mon, 3 Apr 2023 14:38:16 +0000 (16:38 +0200)
The VS signal change is synchronized to HS signal change, start the
info graphics with that event, instead of having that event occur in
the middle of it.

Scope trace of DPI bus with HS/VS active HIGH looks as follows:
         ________________...__
VS...___/__         __        \______...
HS...___/  \_______/  \__...__/  \___...
        ^                        ^
|                        |
        |    Used to start here -'
|
'--- Start info graphics here

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230221200407.16531-1-marex@denx.de
Documentation/devicetree/bindings/display/panel/panel-timing.yaml

index 0d317e6..aea69b8 100644 (file)
@@ -17,29 +17,29 @@ description: |
 
   The parameters are defined as seen in the following illustration.
 
-  +----------+-------------------------------------+----------+-------+
-  |          |        ^                            |          |       |
-  |          |        |vback_porch                 |          |       |
-  |          |        v                            |          |       |
-  +----------#######################################----------+-------+
-  |          #        ^                            #          |       |
-  |          #        |                            #          |       |
-  |  hback   #        |                            #  hfront  | hsync |
-  |   porch  #        |       hactive              #  porch   |  len  |
-  |<-------->#<-------+--------------------------->#<-------->|<----->|
-  |          #        |                            #          |       |
-  |          #        |vactive                     #          |       |
-  |          #        |                            #          |       |
-  |          #        v                            #          |       |
-  +----------#######################################----------+-------+
-  |          |        ^                            |          |       |
-  |          |        |vfront_porch                |          |       |
-  |          |        v                            |          |       |
-  +----------+-------------------------------------+----------+-------+
-  |          |        ^                            |          |       |
-  |          |        |vsync_len                   |          |       |
-  |          |        v                            |          |       |
-  +----------+-------------------------------------+----------+-------+
+  +-------+----------+-------------------------------------+----------+
+  |       |          |        ^                            |          |
+  |       |          |        |vsync_len                   |          |
+  |       |          |        v                            |          |
+  +-------+----------+-------------------------------------+----------+
+  |       |          |        ^                            |          |
+  |       |          |        |vback_porch                 |          |
+  |       |          |        v                            |          |
+  +-------+----------#######################################----------+
+  |       |          #        ^                            #          |
+  |       |          #        |                            #          |
+  | hsync |  hback   #        |                            #  hfront  |
+  |  len  |   porch  #        |       hactive              #  porch   |
+  |<----->|<-------->#<-------+--------------------------->#<-------->|
+  |       |          #        |                            #          |
+  |       |          #        |vactive                     #          |
+  |       |          #        |                            #          |
+  |       |          #        v                            #          |
+  +-------+----------#######################################----------+
+  |       |          |        ^                            |          |
+  |       |          |        |vfront_porch                |          |
+  |       |          |        v                            |          |
+  +-------+----------+-------------------------------------+----------+
 
 
   The following is the panel timings shown with time on the x-axis.