linux-stable/Documentation/devicetree/bindings/display/allwinner,sun4i-a10-display-engine.yaml
Rob Herring 39bd2b6a37 dt-bindings: Improve phandle-array schemas
The 'phandle-array' type is a bit ambiguous. It can be either just an
array of phandles or an array of phandles plus args. Many schemas for
phandle-array properties aren't clear in the schema which case applies
though the description usually describes it.

The array of phandles case boils down to needing:

items:
  maxItems: 1

The phandle plus args cases should typically take this form:

items:
  - items:
      - description: A phandle
      - description: 1st arg cell
      - description: 2nd arg cell

With this change, some examples need updating so that the bracketing of
property values matches the schema.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Georgi Djakov <djakov@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220119015038.2433585-1-robh@kernel.org
2022-02-04 09:43:42 -06:00

116 lines
3.5 KiB
YAML

# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/display/allwinner,sun4i-a10-display-engine.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Allwinner A10 Display Engine Pipeline Device Tree Bindings
maintainers:
- Chen-Yu Tsai <wens@csie.org>
- Maxime Ripard <mripard@kernel.org>
description: |
The display engine pipeline (and its entry point, since it can be
either directly the backend or the frontend) is represented as an
extra node.
The Allwinner A10 Display pipeline is composed of several components
that are going to be documented below:
For all connections between components up to the TCONs in the
display pipeline, when there are multiple components of the same
type at the same depth, the local endpoint ID must be the same as
the remote component's index. For example, if the remote endpoint is
Frontend 1, then the local endpoint ID must be 1.
Frontend 0 [0] ------- [0] Backend 0 [0] ------- [0] TCON 0
[1] -- -- [1] [1] -- -- [1]
\ / \ /
X X
/ \ / \
[0] -- -- [0] [0] -- -- [0]
Frontend 1 [1] ------- [1] Backend 1 [1] ------- [1] TCON 1
For a two pipeline system such as the one depicted above, the lines
represent the connections between the components, while the numbers
within the square brackets corresponds to the ID of the local endpoint.
The same rule also applies to DE 2.0 mixer-TCON connections:
Mixer 0 [0] ----------- [0] TCON 0
[1] ---- ---- [1]
\ /
X
/ \
[0] ---- ---- [0]
Mixer 1 [1] ----------- [1] TCON 1
properties:
compatible:
enum:
- allwinner,sun4i-a10-display-engine
- allwinner,sun5i-a10s-display-engine
- allwinner,sun5i-a13-display-engine
- allwinner,sun6i-a31-display-engine
- allwinner,sun6i-a31s-display-engine
- allwinner,sun7i-a20-display-engine
- allwinner,sun8i-a23-display-engine
- allwinner,sun8i-a33-display-engine
- allwinner,sun8i-a83t-display-engine
- allwinner,sun8i-h3-display-engine
- allwinner,sun8i-r40-display-engine
- allwinner,sun8i-v3s-display-engine
- allwinner,sun9i-a80-display-engine
- allwinner,sun50i-a64-display-engine
- allwinner,sun50i-h6-display-engine
allwinner,pipelines:
$ref: /schemas/types.yaml#/definitions/phandle-array
minItems: 1
maxItems: 2
items:
maxItems: 1
description: |
Available display engine frontends (DE 1.0) or mixers (DE
2.0/3.0) available.
required:
- compatible
- allwinner,pipelines
additionalProperties: false
if:
properties:
compatible:
contains:
enum:
- allwinner,sun4i-a10-display-engine
- allwinner,sun6i-a31-display-engine
- allwinner,sun6i-a31s-display-engine
- allwinner,sun7i-a20-display-engine
- allwinner,sun8i-a83t-display-engine
- allwinner,sun8i-r40-display-engine
- allwinner,sun9i-a80-display-engine
- allwinner,sun50i-a64-display-engine
then:
properties:
allwinner,pipelines:
minItems: 2
else:
properties:
allwinner,pipelines:
maxItems: 1
examples:
- |
de: display-engine {
compatible = "allwinner,sun4i-a10-display-engine";
allwinner,pipelines = <&fe0>, <&fe1>;
};
...