Re: [PATCH v2 3/4] media: dt-bindings: add bindings for Toshiba TC358746

From: Laurent Pinchart
Date: Sat Sep 17 2022 - 19:07:12 EST


Hi Marco,

Thank you for the patch.

On Fri, Sep 16, 2022 at 03:45:34PM +0200, Marco Felsch wrote:
> Add the bindings for the Toshiba TC358746 Parallel <-> MIPI-CSI bridge
> driver.
>
> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> Changelog:
>
> v2:
> - addded Robs r-b
> - s/than/then/
> - added hsync/vsync/bus-type, make hsync/vsync required
> - fix example indent
>
> .../bindings/media/i2c/toshiba,tc358746.yaml | 179 ++++++++++++++++++
> 1 file changed, 179 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.yaml
>
> diff --git a/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.yaml b/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.yaml
> new file mode 100644
> index 000000000000..1fa574400bc2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.yaml
> @@ -0,0 +1,179 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/i2c/toshiba,tc358746.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Toshiba TC358746 Parallel to MIPI CSI2 Bridge
> +
> +maintainers:
> + - Marco Felsch <kernel@xxxxxxxxxxxxxx>
> +
> +description: |-
> + The Toshiba TC358746 converts a parallel video stream into a MIPI CSI-2
> + stream. The direction can be either parallel-in -> csi-out or csi-in ->
> + parallel-out The chip is programmable trough I2C and SPI but the SPI
> + interface is only supported in parallel-in -> csi-out mode.
> +
> + Note that the current device tree bindings only support the
> + parallel-in -> csi-out path.
> +
> +properties:
> + compatible:
> + const: toshiba,tc358746
> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + description:
> + The phandle to the reference clock source. This corresponds to the
> + hardware pin REFCLK.
> + maxItems: 1
> +
> + clock-names:
> + const: refclk
> +
> +# The bridge can act as clock provider for the sensor. To enable this support
> +# #clock-cells must be specified. Attention if this feature is used then the
> +# mclk rate must be at least: (2 * link-frequency) / 8
> +# `------------------´ ^
> +# internal PLL rate smallest possible mclk-div
> + "#clock-cells":
> + const: 0
> +
> + clock-output-names:
> + description:
> + The clock name of the MCLK output, the default name is tc358746-mclk.
> + maxItems: 1
> +
> + vddc-supply:
> + description: Digital core voltage supply, 1.2 volts
> +
> + vddio-supply:
> + description: Digital I/O voltage supply, 1.8 volts
> +
> + vddmipi-supply:
> + description: MIPI CSI phy voltage supply, 1.2 volts
> +
> + reset-gpios:
> + description:
> + The phandle and specifier for the GPIO that controls the chip reset.
> + This corresponds to the hardware pin RESX which is physically active low.
> + maxItems: 1
> +
> + ports:
> + $ref: /schemas/graph.yaml#/properties/ports
> + properties:
> + port@0:
> + $ref: /schemas/graph.yaml#/$defs/port-base
> + description: Input port
> +
> + properties:
> + endpoint:
> + $ref: /schemas/media/video-interfaces.yaml#
> + unevaluatedProperties: false
> +
> + properties:
> + hsync-active:
> + enum:
> + - 0 # Hvalid active high
> + vsync-active:
> + enum:
> + - 0 # Vvalid active high
> + bus-type:
> + enum:
> + - 5 # Parallel
> +
> + required:
> + - hsync-active
> + - vsync-active

Let's make bus-type required too, to prepare for BT.656 support.

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> +
> + port@1:
> + $ref: /schemas/graph.yaml#/$defs/port-base
> + description: Output port
> +
> + properties:
> + endpoint:
> + $ref: /schemas/media/video-interfaces.yaml#
> + unevaluatedProperties: false
> +
> + properties:
> + data-lanes:
> + minItems: 1
> + maxItems: 4
> +
> + clock-noncontinuous: true
> + link-frequencies: true
> +
> + required:
> + - data-lanes
> + - link-frequencies
> +
> + required:
> + - port@0
> + - port@1
> +
> +required:
> + - compatible
> + - reg
> + - clocks
> + - clock-names
> + - vddc-supply
> + - vddio-supply
> + - vddmipi-supply
> + - ports
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> +
> + i2c {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + csi-bridge@e {
> + compatible = "toshiba,tc358746";
> + reg = <0xe>;
> +
> + clocks = <&refclk>;
> + clock-names = "refclk";
> +
> + reset-gpios = <&gpio 2 GPIO_ACTIVE_LOW>;
> +
> + vddc-supply = <&v1_2d>;
> + vddio-supply = <&v1_8d>;
> + vddmipi-supply = <&v1_2d>;
> +
> + /* sensor mclk provider */
> + #clock-cells = <0>;
> +
> + ports {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + /* Input */
> + port@0 {
> + reg = <0>;
> + tc358746_in: endpoint {
> + remote-endpoint = <&sensor_out>;
> + hsync-active = <0>;
> + vsync-active = <0>;
> + };
> + };
> +
> + /* Output */
> + port@1 {
> + reg = <1>;
> + tc358746_out: endpoint {
> + remote-endpoint = <&mipi_csi2_in>;
> + data-lanes = <1 2>;
> + clock-noncontinuous;
> + link-frequencies = /bits/ 64 <216000000>;
> + };
> + };
> + };
> + };
> + };

--
Regards,

Laurent Pinchart