xref: /linux/Documentation/devicetree/bindings/display/panel/tpo,tpg110.yaml (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e) 
1# SPDX-License-Identifier: GPL-2.0
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/display/panel/tpo,tpg110.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: TPO TPG110 Panel
8
9maintainers:
10  - Linus Walleij <linus.walleij@linaro.org>
11  - Thierry Reding <thierry.reding@gmail.com>
12
13description: |+
14  This panel driver is a component that acts as an intermediary
15  between an RGB output and a variety of panels. The panel
16  driver is strapped up in electronics to the desired resolution
17  and other properties, and has a control interface over 3WIRE
18  SPI. By talking to the TPG110 over SPI, the strapped properties
19  can be discovered and the hardware is therefore mostly
20  self-describing.
21
22         +--------+
23  SPI -> |  TPO   | -> physical display
24  RGB -> | TPG110 |
25         +--------+
26
27  If some electrical strap or alternate resolution is desired,
28  this can be set up by taking software control of the display
29  over the SPI interface. The interface can also adjust
30  for properties of the display such as gamma correction and
31  certain electrical driving levels.
32
33  The TPG110 does not know the physical dimensions of the panel
34  connected, so this needs to be specified in the device tree.
35
36  It requires a GPIO line for control of its reset line.
37
38  The serial protocol has line names that resemble I2C but the
39  protocol is not I2C but 3WIRE SPI.
40
41
42allOf:
43  - $ref: panel-common.yaml#
44
45properties:
46  compatible:
47    oneOf:
48      - items:
49          - enum:
50              - ste,nomadik-nhk15-display
51          - const: tpo,tpg110
52      - const: tpo,tpg110
53
54  reg: true
55
56  grestb-gpios:
57    maxItems: 1
58    description: panel reset GPIO
59
60  spi-3wire: true
61
62  spi-max-frequency:
63    const: 3000000
64
65required:
66  - compatible
67  - reg
68  - grestb-gpios
69  - width-mm
70  - height-mm
71  - spi-3wire
72  - spi-max-frequency
73  - port
74
75unevaluatedProperties: false
76
77examples:
78  - |+
79    spi {
80      #address-cells = <1>;
81      #size-cells = <0>;
82
83      panel: display@0 {
84        compatible = "tpo,tpg110";
85        reg = <0>;
86        spi-3wire;
87        /* 320 ns min period ~= 3 MHz */
88        spi-max-frequency = <3000000>;
89        /* Width and height from data sheet */
90        width-mm = <116>;
91        height-mm = <87>;
92        grestb-gpios = <&foo_gpio 5 1>;
93        backlight = <&bl>;
94
95        port {
96          nomadik_clcd_panel: endpoint {
97            remote-endpoint = <&foo>;
98          };
99        };
100      };
101    };
102
103...
104