[PATCH V4 1/2] dt-bindings: display: bridge: lvds-codec: Document pixel data sampling edge select

[PATCH V4 1/2] dt-bindings: display: bridge: lvds-codec: Document pixel data sampling edge select

[Marek Vasut]

The OnSemi FIN3385 Parallel-to-LVDS encoder has a dedicated input line to
select input pixel data sampling edge. Add DT property "pclk-sample", not
the same as the one used by display timings but rather the same as used by
media, to define the pixel data sampling edge.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Antonio Borneo <antonio.borneo@st.com>
Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Biju Das <biju.das.jz@bp.renesas.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Philippe Cornu <philippe.cornu@st.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Yannick Fertre <yannick.fertre@st.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
To: dri-devel@lists.freedesktop.org
---
V4: New patch split from combined V3
---
 .../bindings/display/bridge/lvds-codec.yaml    | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
index 304a1367faaa..f4dd16bd69d2 100644
--- a/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
@@ -64,6 +64,14 @@ properties:
       - port@0
       - port@1
 
+  pclk-sample:
+    description:
+      Data sampling on rising or falling edge.
+    enum:
+      - 0  # Falling edge
+      - 1  # Rising edge
+    default: 0
+
   powerdown-gpios:
     description:
       The GPIO used to control the power down line of this device.
@@ -71,6 +79,16 @@ properties:
 
   power-supply: true
 
+if:
+  not:
+    properties:
+      compatible:
+        contains:
+          const: lvds-encoder
+then:
+  properties:
+    pclk-sample: false
+
 required:
   - compatible
   - ports
-- 
2.30.2

Re: [PATCH V4 1/2] dt-bindings: display: bridge: lvds-codec: Document pixel data sampling edge select

[Rob Herring]

On Sat, May 15, 2021 at 10:43:15PM +0200, Marek Vasut wrote:
> The OnSemi FIN3385 Parallel-to-LVDS encoder has a dedicated input line to
> select input pixel data sampling edge. Add DT property "pclk-sample", not
> the same as the one used by display timings but rather the same as used by
> media, to define the pixel data sampling edge.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Alexandre Torgue <alexandre.torgue@st.com>
> Cc: Andrzej Hajda <a.hajda@samsung.com>
> Cc: Antonio Borneo <antonio.borneo@st.com>
> Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
> Cc: Biju Das <biju.das.jz@bp.renesas.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> Cc: Philippe Cornu <philippe.cornu@st.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> Cc: Vincent Abriou <vincent.abriou@st.com>
> Cc: Yannick Fertre <yannick.fertre@st.com>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-stm32@st-md-mailman.stormreply.com
> To: dri-devel@lists.freedesktop.org
> ---
> V4: New patch split from combined V3
> ---
>  .../bindings/display/bridge/lvds-codec.yaml    | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> index 304a1367faaa..f4dd16bd69d2 100644
> --- a/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> @@ -64,6 +64,14 @@ properties:
>        - port@0
>        - port@1
>  
> +  pclk-sample:
> +    description:
> +      Data sampling on rising or falling edge.
> +    enum:
> +      - 0  # Falling edge
> +      - 1  # Rising edge
> +    default: 0

This is already defined in video-interfaces.yaml, why are you redefining 
it here?

It's also defined to be an endpoint property, so move it there and 
reference video-interfaces.yaml.

> +
>    powerdown-gpios:
>      description:
>        The GPIO used to control the power down line of this device.
> @@ -71,6 +79,16 @@ properties:
>  
>    power-supply: true
>  
> +if:
> +  not:
> +    properties:
> +      compatible:
> +        contains:
> +          const: lvds-encoder
> +then:
> +  properties:
> +    pclk-sample: false

This constraint would be difficult to express with the property in an 
endpoint. I'd just drop it.

Rob