Hi Sebastian,

Thank you for the patch.

On Thu, Feb 27, 2020 at 09:35:21PM +0100, Sam Ravnborg wrote:

On Tue, Feb 25, 2020 at 12:53:41PM +0100, Sebastian Reichel wrote:

...

Convert panel-dsi-cm bindings to YAML and add missing properties while at it.

Signed-off-by: Sebastian Reichel sebastian.reichel@collabora.com

As saind in previous mail - I prefer to convert ann then patch. But end result is the same so OK.

I agree, splitting the patch would be better.

...

---

.../bindings/display/panel/panel-dsi-cm.txt | 31 ------ .../bindings/display/panel/panel-dsi-cm.yaml | 97 +++++++++++++++++++ 2 files changed, 97 insertions(+), 31 deletions(-) delete mode 100644 Documentation/devicetree/bindings/display/panel/panel-dsi-cm.txt create mode 100644 Documentation/devicetree/bindings/display/panel/panel-dsi-cm.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.txt b/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.txt deleted file mode 100644 index f92d5c9adfc5..000000000000 --- a/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.txt +++ /dev/null @@ -1,31 +0,0 @@

-Generic MIPI DSI Command Mode Panel

-Required properties: -- compatible: "panel-dsi-cm" -- reg: DSI channel number

-Optional properties: -- label: a symbolic name for the panel -- reset-gpios: panel reset gpio -- te-gpios: panel TE gpio

-Required nodes: -- Video port for DSI input

-Example

-lcd0: panel@0 {

• compatible = "tpo,taal", "panel-dsi-cm";
• label = "lcd0";
• reg = <0>;
• reset-gpios = <&gpio4 6 GPIO_ACTIVE_HIGH>;
• port {

• lcd0_in: endpoint {
  

• 	remote-endpoint = <&dsi1_out_ep>;
  

• };
  

• };

-}; diff --git a/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.yaml b/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.yaml new file mode 100644 index 000000000000..ca61171ae145 --- /dev/null +++ b/Documentation/devicetree/bindings/display/panel/panel-dsi-cm.yaml @@ -0,0 +1,97 @@ +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/display/panel/panel-dsi-cm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: DSI command mode panels

+maintainers:

• • Tomi Valkeinen tomi.valkeinen@ti.com
• • Sebastian Reichel sre@kernel.org

+description: |

• This binding file is a collection of the DSI panels that
• are usually driven in command mode. If no backlight is
• referenced via the optional backlight property, the DSI
• panel is assumed to have native backlight support.

Maybe this sentence could be moved to the description of the backlight property ? Or would it override the description from panel-common.yaml ? If so, is there a way in the yaml bindings syntax to extend that property ?

...

• The panel may use an OF graph binding for the association
• to the display, or it may be a direct child node of the
• display.

+allOf:

• • $ref: panel-common.yaml#

+properties:

• compatible:
• enum:

•  # compatible must be listed in alphabetical order, ordered by compatible.
  

•  # The description in the comment is mandatory for each compatible.
  

•  - motorola,droid4-panel, panel-dsi-cm
  

•  - nokia,himalaya, panel-dsi-cm
  

•  - tpo,taal, panel-dsi-cm
  

Please consider to use the following syntax (from memory - may require an enum:):

compatible: description: Shall contain a panel specific compatible and "panel-dsi-cm" in that order. items: - oneOf: # Maybe add a short description of this panel - motorola,droid4-panel # Maybe add a short description of this panel

• nokia,himalaya # Maybe add a short description of this panel

• tpo,taal

  • const: panel-dsi-cm

Then panel-dsi-cm is always specified as a second mandatory compatible.

This is not only nicer, but it's actually correct, while the original version isn't. The original version would require, for instance,

compatible = "motorola,droid4-panel, panel-dsi-cm";

and not

compatible = "motorola,droid4-panel", "panel-dsi-cm";

...

• reg:
• maxItems: 1
• description: DSI virtual channel
• te-gpios:
• maxItems: 1
• description:

•  Specifier for a GPIO connected to the panel TE (tearing event) signal.
  

•  The GPIO informs the system, that data should be sent to the display
  

•  on rising edges of the GPIO to avoid (or reduce) tearing effects.
  

•  Falling edge can be supported by inverting the GPIO specifier polarity
  

•  flag.
  

te-gpios is used by several panels. Please add it to panel-common with your nice description.

Possible too late to change this, but shouldn't we really have used

interrupts = <...>; interrupt-names = "te";

?

The TE signal may be connected to an interrupt pin that is not a GPIO.

With the above addressed: Reviewed-by: Sam Ravnborg sam@ravnborg.org

...

• vddi-supply:
• description:

•  Display panels require power to be supplied. While several panels need
  

•  more than one power supply with panel-specific constraints governing the
  

•  order and timings of the power supplies, in many cases a single power
  

•  supply is sufficient, either because the panel has a single power rail, or
  

•  because all its power rails can be driven by the same supply. In that case
  

•  the vddi-supply property specifies the supply powering the panel as a
  

•  phandle to a regulator.
  

• vpnl-supply:
• description:

•  When the display panel needs a second power supply, this property can be
  

•  used in addition to vddi-supply. Both supplies will be enabled at the
  

•  same time before the panel is being accessed.
  

Too late for this too, but I wonder if the best practice for this kind of cases wouldn't be to specify a single supply that would be modelled by a regulator with multiple inputs.

...

• width-mm: true
• height-mm: true
• label: true
• rotation: true
• panel-timing: true
• port: true
• reset-gpios: true
• backlight: true

+additionalProperties: false

+required:

• • compatible
• • port

You wrote in the overall description that the panel may have a port node or may be a child of the DSI controller. Doesn't that make port optional ?

Should we require width-mm and height-mm ?

...

• • reg

+examples:

• • |
• dsi1@12345678 {

•  #address-cells = <1>;
  

•  #size-cells = <0>;
  

•  panel@0 {
  

•    compatible = "tpo,taal", "panel-dsi-cm";
  

•    label = "lcd0";
  

•    reg = <0>;
  

•    reset-gpios = <&gpio4 6 GPIO_ACTIVE_HIGH>;
  

•    port {
  

•      panel: endpoint {
  

•        remote-endpoint = <&dsi1_out_ep>;
  

•      };
  

•    };
  

•  };
  

• };