Documentation/devicetree/bindings/display/allwinner,sun4i-a10-display-engine.yaml

   1 # SPDX-License-Identifier: GPL-2.0
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/display/allwinner,sun4i-a10-display-engine.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: Allwinner A10 Display Engine Pipeline Device Tree Bindings
   8
   9 maintainers:
  10   - Chen-Yu Tsai <wens@csie.org>
  11   - Maxime Ripard <mripard@kernel.org>
  12
  13 description: |
  14   The display engine pipeline (and its entry point, since it can be
  15   either directly the backend or the frontend) is represented as an
  16   extra node.
  17
  18   The Allwinner A10 Display pipeline is composed of several components
  19   that are going to be documented below:
  20
  21   For all connections between components up to the TCONs in the
  22   display pipeline, when there are multiple components of the same
  23   type at the same depth, the local endpoint ID must be the same as
  24   the remote component's index. For example, if the remote endpoint is
  25   Frontend 1, then the local endpoint ID must be 1.
  26
  27   Frontend 0  [0] ------- [0]  Backend 0  [0] ------- [0]  TCON 0
  28               [1] --   -- [1]             [1] --   -- [1]
  29                     \ /                         \ /
  30                      X                           X
  31                     / \                         / \
  32               [0] --   -- [0]             [0] --   -- [0]
  33   Frontend 1  [1] ------- [1]  Backend 1  [1] ------- [1]  TCON 1
  34
  35   For a two pipeline system such as the one depicted above, the lines
  36   represent the connections between the components, while the numbers
  37   within the square brackets corresponds to the ID of the local endpoint.
  38
  39   The same rule also applies to DE 2.0 mixer-TCON connections:
  40
  41   Mixer 0  [0] ----------- [0]  TCON 0
  42            [1] ----   ---- [1]
  43                    \ /
  44                     X
  45                    / \
  46            [0] ----   ---- [0]
  47   Mixer 1  [1] ----------- [1]  TCON 1
  48
  49 properties:
  50   compatible:
  51     enum:
  52       - allwinner,sun4i-a10-display-engine
  53       - allwinner,sun5i-a10s-display-engine
  54       - allwinner,sun5i-a13-display-engine
  55       - allwinner,sun6i-a31-display-engine
  56       - allwinner,sun6i-a31s-display-engine
  57       - allwinner,sun7i-a20-display-engine
  58       - allwinner,sun8i-a23-display-engine
  59       - allwinner,sun8i-a33-display-engine
  60       - allwinner,sun8i-a83t-display-engine
  61       - allwinner,sun8i-h3-display-engine
  62       - allwinner,sun8i-r40-display-engine
  63       - allwinner,sun8i-v3s-display-engine
  64       - allwinner,sun9i-a80-display-engine
  65       - allwinner,sun50i-a64-display-engine
  66       - allwinner,sun50i-h6-display-engine
  67
  68   allwinner,pipelines:
  69     $ref: /schemas/types.yaml#/definitions/phandle-array
  70     minItems: 1
  71     maxItems: 2
  72     description: |
  73       Available display engine frontends (DE 1.0) or mixers (DE
  74       2.0/3.0) available.
  75
  76 required:
  77   - compatible
  78   - allwinner,pipelines
  79
  80 additionalProperties: false
  81
  82 if:
  83   properties:
  84     compatible:
  85       contains:
  86         enum:
  87           - allwinner,sun4i-a10-display-engine
  88           - allwinner,sun6i-a31-display-engine
  89           - allwinner,sun6i-a31s-display-engine
  90           - allwinner,sun7i-a20-display-engine
  91           - allwinner,sun8i-a83t-display-engine
  92           - allwinner,sun8i-r40-display-engine
  93           - allwinner,sun9i-a80-display-engine
  94           - allwinner,sun50i-a64-display-engine
  95
  96 then:
  97   properties:
  98     allwinner,pipelines:
  99       minItems: 2
 100
 101 else:
 102   properties:
 103     allwinner,pipelines:
 104       maxItems: 1
 105
 106 examples:
 107   - |
 108       de: display-engine {
 109           compatible = "allwinner,sun4i-a10-display-engine";
 110           allwinner,pipelines = <&fe0>, <&fe1>;
 111       };
 112
 113 ...