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,sun20i-d1-display-engine
  66       - allwinner,sun50i-a64-display-engine
  67       - allwinner,sun50i-h6-display-engine
  68
  69   allwinner,pipelines:
  70     $ref: /schemas/types.yaml#/definitions/phandle-array
  71     minItems: 1
  72     maxItems: 2
  73     items:
  74       maxItems: 1
  75     description: |
  76       Available display engine frontends (DE 1.0) or mixers (DE
  77       2.0/3.0) available.
  78
  79 required:
  80   - compatible
  81   - allwinner,pipelines
  82
  83 additionalProperties: false
  84
  85 if:
  86   properties:
  87     compatible:
  88       contains:
  89         enum:
  90           - allwinner,sun4i-a10-display-engine
  91           - allwinner,sun6i-a31-display-engine
  92           - allwinner,sun6i-a31s-display-engine
  93           - allwinner,sun7i-a20-display-engine
  94           - allwinner,sun8i-a83t-display-engine
  95           - allwinner,sun8i-r40-display-engine
  96           - allwinner,sun9i-a80-display-engine
  97           - allwinner,sun50i-a64-display-engine
  98
  99 then:
 100   properties:
 101     allwinner,pipelines:
 102       minItems: 2
 103
 104 else:
 105   properties:
 106     allwinner,pipelines:
 107       maxItems: 1
 108
 109 examples:
 110   - |
 111       de: display-engine {
 112           compatible = "allwinner,sun4i-a10-display-engine";
 113           allwinner,pipelines = <&fe0>, <&fe1>;
 114       };
 115
 116 ...