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