Re: [PATCH v7 5/8] dt-bindings: display: add i.MX6 MIPI DSI host controller doc

From: Laurent Pinchart
Date: Tue Apr 21 2020 - 21:02:16 EST

Hi Adrian,

On Wed, Apr 22, 2020 at 03:58:33AM +0300, Laurent Pinchart wrote:
> On Tue, Apr 21, 2020 at 07:16:07PM +0300, Adrian Ratiu wrote:
> > This provides an example DT binding for the MIPI DSI host controller
> > present on the i.MX6 SoC based on Synopsis DesignWare v1.01 IP.
> >
> > Cc: Rob Herring <robh@xxxxxxxxxx>
> > Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> > Cc: Fabio Estevam <festevam@xxxxxxxxx>
> > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > Cc: devicetree@xxxxxxxxxxxxxxx
> > Tested-by: Adrian Pop <pop.adrian61@xxxxxxxxx>
> > Tested-by: Arnaud Ferraris <arnaud.ferraris@xxxxxxxxxxxxx>
> > Signed-off-by: Sjoerd Simons <sjoerd.simons@xxxxxxxxxxxxx>
> > Signed-off-by: Martyn Welch <martyn.welch@xxxxxxxxxxxxx>
> > Signed-off-by: Adrian Ratiu <adrian.ratiu@xxxxxxxxxxxxx>
> > ---
> > Changes since v6:
> > - Added ref to the newly created snps,dw-mipi-dsi.yaml (Laurent)
> > - Moved *-cells properties outside patternProperties (Laurent)
> > - Removed the panel port documentation (Laurent)
> > - Wrapped lines at 80 chars, typo fixes, sort includes (Laurent)
> >
> > Changes since v5:
> > - Fixed missing reg warning (Fabio)
> > - Updated dt-schema and fixed warnings (Rob)
> >
> > Changes since v4:
> > - Fixed yaml binding to pass `make dt_binding_check dtbs_check`
> > and addressed received binding feedback (Rob)
> >
> > Changes since v3:
> > - Added commit message (Neil)
> > - Converted to yaml format (Neil)
> > - Minor dt node + driver fixes (Rob)
> > - Added small panel example to the host controller binding
> >
> > Changes since v2:
> > - Fixed commit tags (Emil)
> > ---
> > .../display/imx/fsl,mipi-dsi-imx6.yaml | 135 ++++++++++++++++++
> > 1 file changed, 135 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/display/imx/fsl,mipi-dsi-imx6.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/display/imx/fsl,mipi-dsi-imx6.yaml b/Documentation/devicetree/bindings/display/imx/fsl,mipi-dsi-imx6.yaml
> > new file mode 100644
> > index 0000000000000..b73e3ae33a852
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/imx/fsl,mipi-dsi-imx6.yaml
> > @@ -0,0 +1,135 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/imx/fsl,mipi-dsi-imx6.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Freescale i.MX6 DW MIPI DSI Host Controller
> > +
> > +maintainers:
> > + - Adrian Ratiu <adrian.ratiu@xxxxxxxxxxxxx>
> > +
> > +description: |
> > + The i.MX6 DSI host controller is a Synopsys DesignWare MIPI DSI v1.01
> > + IP block with a companion PHY IP.

I forgot to mention, if there's a companion PHY, shouldn't it be
referenced from the DT bindings ?

> > +
> > + These DT bindings follow the Synopsys DW MIPI DSI bindings defined in
> > + Documentation/devicetree/bindings/display/bridge/dw_mipi_dsi.txt with
> > + the following device-specific properties.
> > +
> > +allOf:
> > + - $ref: ../bridge/snps,dw-mipi-dsi.yaml#
> > +
> > +properties:
> > + '#address-cells':
> > + const: 1
> > +
> > + '#size-cells':
> > + const: 0
> > +
> > + compatible:
> > + items:
> > + - const: fsl,imx6q-mipi-dsi
> > + - const: snps,dw-mipi-dsi
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + interrupts:
> > + maxItems: 1
> > +
> > + clocks:
> > + items:
> > + - description: Module Clock
> > + - description: DSI bus clock
> > +
> > + clock-names:
> > + items:
> > + - const: ref
> > + - const: pclk
> > +
> > + fsl,gpr:
> > + description:
> > + Phandle to the iomuxc-gpr region containing the multiplexer ctrl register.
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > +
> > + ports:
> > + type: object
> > + description: |
> > + A node containing DSI input & output port nodes with endpoint
> > + definitions as documented in
> > + Documentation/devicetree/bindings/media/video-interfaces.txt
> > + Documentation/devicetree/bindings/graph.txt
> > + properties:
> > + port@0:
> > + type: object
> > + description:
> > + DSI input port node, connected to the ltdc rgb output port.
> > +
> > + port@1:
> > + type: object
> > + description:
> > + RGB output port node, connected to a panel or a bridge input port.
>
> Isn't it the other way around, doesn't the bridge take RGB input and
> output DSI ? And to be precise, it's not about RGB, but about the input
> being parallel interface (DSI will also carry RGB).
>
> I would add
>
> required:
> - port@0
> - port@1
>
> > +
> > +additionalProperties: false
> > +
> > +patternProperties:
> > + "^panel@[0-3]$":
> > + type: object
> > +
> > +required:
> > + - "#address-cells"
> > + - "#size-cells"
> > + - compatible
> > + - reg
> > + - interrupts
> > + - clocks
> > + - clock-names
> > + - ports
> > +
> > +examples:
> > + - |+
> > + #include <dt-bindings/clock/imx6qdl-clock.h>
> > + #include <dt-bindings/gpio/gpio.h>
> > + #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +
> > + dsi: dsi@21e0000 {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > + compatible = "fsl,imx6q-mipi-dsi", "snps,dw-mipi-dsi";
> > + reg = <0x021e0000 0x4000>;
> > + interrupts = <0 102 IRQ_TYPE_LEVEL_HIGH>;
> > + fsl,gpr = <&gpr>;
> > + clocks = <&clks IMX6QDL_CLK_MIPI_CORE_CFG>,
> > + <&clks IMX6QDL_CLK_MIPI_IPG>;
> > + clock-names = "ref", "pclk";
> > +
> > + ports {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
>
> port@0 is missing.
>
> > + port@1 {
> > + reg = <1>;
> > + dsi_out: endpoint {
> > + remote-endpoint = <&panel_in>;
> > + };
> > + };
> > + };
> > +
> > + panel@0 {
> > + compatible = "sharp,ls032b3sx01";
> > + reg = <0>;
> > + reset-gpios = <&gpio6 8 GPIO_ACTIVE_LOW>;
> > + ports {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > + port@0 {
> > + reg = <0>;
> > + panel_in: endpoint {
> > + remote-endpoint = <&dsi_out>;
> > + };
> > + };
> > + };
> > + };
> > + };
> > +
> > +...

--
Regards,

Laurent Pinchart