Re: [PATCH V8 09/12] dt-bindings: display: imx: add binding for i.MX8MP HDMI TX

Adam Ford
2024-02-16T11:31:24Z

On Fri, Feb 16, 2024 at 3:05 AM Alexander Stein
<alexander.stein@ew.tq-group.com> wrote:
>
> Hi all,
>
> Am Samstag, 3. Februar 2024, 17:52:49 CET schrieb Adam Ford:
> > From: Lucas Stach <l.stach@pengutronix.de>
> >
> > The HDMI TX controller on the i.MX8MP SoC is a Synopsys designware IP
> > core with a little bit of SoC integration around it.
> >
> > Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> > Signed-off-by: Adam Ford <aford173@gmail.com>
> >
> > ---
> > V3: Change name and location to better idenfity as a bridge and
> > HDMI 2.0a transmitter
> >
> > Fix typos and feedback from Rob and added ports.
> > ---
> > .../display/bridge/fsl,imx8mp-hdmi-tx.yaml | 102 ++++++++++++++++++
> > 1 file changed, 102 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/display/bridge/fsl,imx8mp-hdmi-tx.yaml
> >
> > diff --git
> > a/Documentation/devicetree/bindings/display/bridge/fsl,imx8mp-hdmi-tx.yaml
> > b/Documentation/devicetree/bindings/display/bridge/fsl,imx8mp-hdmi-tx.yaml
> > new file mode 100644
> > index 000000000000..3791c9f4ebab
> > --- /dev/null
> > +++
> > b/Documentation/devicetree/bindings/display/bridge/fsl,imx8mp-hdmi-tx.yaml
> > @@ -0,0 +1,102 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/bridge/fsl,imx8mp-hdmi-tx.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Freescale i.MX8MP DWC HDMI TX Encoder
> > +
> > +maintainers:
> > + - Lucas Stach <l.stach@pengutronix.de>
> > +
> > +description:
> > + The i.MX8MP HDMI transmitter is a Synopsys DesignWare
> > + HDMI 2.0a TX controller IP.
> > +
> > +allOf:
> > + - $ref: /schemas/display/bridge/synopsys,dw-hdmi.yaml#
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - fsl,imx8mp-hdmi-tx
> > +
> > + reg-io-width:
> > + const: 1
> > +
> > + clocks:
> > + maxItems: 4
> > +
> > + clock-names:
> > + items:
> > + - const: iahb
> > + - const: isfr
> > + - const: cec
> > + - const: pix
> > +
> > + power-domains:
> > + maxItems: 1
> > +
> > + ports:
> > + $ref: /schemas/graph.yaml#/properties/ports
> > +
> > + properties:
> > + port@0:
> > + $ref: /schemas/graph.yaml#/properties/port
> > + description: Parallel RGB input port
> > +
> > + port@1:
> > + $ref: /schemas/graph.yaml#/properties/port
> > + description: HDMI output port
> > +
> > + required:
> > + - port@0
> > + - port@1
>
> Is this really correct that port@1 is required? AFAICS this host already
> supports HPD and DDC by itself, so there is no need for a dedicated HDMI
> connector.
> With the current state of the drivers this output port is completely ignored
> anyway. Yet it works for a lot of people.

One of the feedback responses Lucas got was that it was missing the
reference to the HDMI connector, so I added it as a response to that
feedback. I have tried device trees with and without it, and it
doesn't impact anything, but It seems like there may be a requirement
for it.

adam
>
> Best regards,
> Alexander
>
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - clocks
> > + - clock-names
> > + - interrupts
> > + - power-domains
> > + - ports
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/clock/imx8mp-clock.h>
> > + #include <dt-bindings/interrupt-controller/irq.h>
> > + #include <dt-bindings/power/imx8mp-power.h>
> > +
> > + hdmi@32fd8000 {
> > + compatible = "fsl,imx8mp-hdmi-tx";
> > + reg = <0x32fd8000 0x7eff>;
> > + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>;
> > + clocks = <&clk IMX8MP_CLK_HDMI_APB>,
> > + <&clk IMX8MP_CLK_HDMI_REF_266M>,
> > + <&clk IMX8MP_CLK_32K>,
> > + <&hdmi_tx_phy>;
> > + clock-names = "iahb", "isfr", "cec", "pix";
> > + power-domains = <&hdmi_blk_ctrl IMX8MP_HDMIBLK_PD_HDMI_TX>;
> > + reg-io-width = <1>;
> > + ports {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > + port@0 {
> > + reg = <0>;
> > +
> > + hdmi_tx_from_pvi: endpoint {
> > + remote-endpoint = <&pvi_to_hdmi_tx>;
> > + };
> > + };
> > +
> > + port@1 {
> > + reg = <1>;
> > + hdmi_tx_out: endpoint {
> > + remote-endpoint = <&hdmi0_con>;
> > + };
> > + };
> > + };
> > + };
>
>
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