Hi Sakari,
Thanks for the review!
On 2/9/24 10:48, Sakari Ailus wrote:
Hi Julien,
On Thu, Jan 11, 2024 at 02:03:47PM +0100, Julien Massot wrote:
Add DT bindings for Maxim MAX96714F GMSL2 Deserializer.
Signed-off-by: Julien Massot <julien.massot@xxxxxxxxxxxxx>
---
Change since v2:
- remove reg description
- rename enable gpio to powerdown
- use generic node name: i2c, serializer, deserializer
---
.../bindings/media/i2c/maxim,max96714f.yaml | 171 ++++++++++++++++++
1 file changed, 171 insertions(+)
create mode 100644 Documentation/devicetree/bindings/media/i2c/maxim,max96714f.yaml
diff --git a/Documentation/devicetree/bindings/media/i2c/maxim,max96714f.yaml b/Documentation/devicetree/bindings/media/i2c/maxim,max96714f.yaml
new file mode 100644
index 000000000000..2423d166c954
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/maxim,max96714f.yaml
@@ -0,0 +1,171 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2024 Collabora Ltd.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/media/i2c/maxim,max96714f.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Maxim MAX96714 GMSL2 to CSI-2 Deserializer
+
+maintainers:
+ - Julien Massot <julien.massot@xxxxxxxxxxxxx>
+
+description: |
+ The MAX96714F deserializer converts GMSL2 serial inputs into MIPI
+ CSI-2 D-PHY or C-PHY formatted output. The device allows the GMSL2 link to
Description is wrong if the MAX96717F is supporting C-PHY MAX96714F doesn't.
I will remove the mention to C-PHY sorry for the confusion.
+ simultaneously transmit bidirectional control-channel data while forward
+ video transmissions are in progress. The MAX96714F can connect to one
+ remotely located serializer using industry-standard coax or STP
+ interconnects. The device cans operate in pixel or tunnel mode. In pixel mode
+ the MAX96714F can select individual video stream, while the tunnel mode forward all
+ the MIPI data received by the serializer.
+
+ The GMSL2 serial link operates at a fixed rate of 3Gbps in the
+ forward direction and 187.5Mbps in the reverse direction.
+
+properties:
+ compatible:
+ const: maxim,max96714f
+
+ reg:
+ maxItems: 1
+
+ powerdown-gpios:
+ maxItems: 1
+ description:
+ Specifier for the GPIO connected to the PWDNB pin.
+
+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ unevaluatedProperties: false
+ description: GMSL Input
+ properties:
+ endpoint:
+ $ref: /schemas/media/video-interfaces.yaml#
+ unevaluatedProperties: false
+ description:
+ Endpoint for GMSL2-Link port.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/$defs/port-base
+ unevaluatedProperties: false
+ description: CSI-2 Output port
+
+ properties:
+ endpoint:
+ $ref: /schemas/media/video-interfaces.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ data-lanes:
+ minItems: 1
+ maxItems: 4
+
+ link-frequencies:
+ maxItems: 1
+
+ bus-type:
+ enum:
+ - 4 # MEDIA_BUS_TYPE_CSI2_DPHY
MEDIA_BUS_TYPE_CSI2_CPHY (1) is missing. Even if the driver doesn't support
it, it would be best to list it here.
After verification the hardware only support D-PHY and not C-PHY, will
drop the required
property for 'bus-type'.
+
+ required:
+ - data-lanes
+ - bus-type
+
+ required:
+ - port@1
Why port@1 but not port@0?
The device can be used as a pattern generator, so this is fine not to
have a serializer connected to the port@0, but it makes no sense to
leave the deserializer CSI port not connected.
+
+ i2c-gate:
+ $ref: /schemas/i2c/i2c-controller.yaml
+ unevaluatedProperties: false
+ description: |
+ The MAX96714 will pass through and forward the I2C requests from the
+ incoming I2C bus over the GMSL2 link. Therefore it supports an i2c-gate
+ subnode to configure a serializer.
+
+ port0-poc-supply:
+ description: Regulator providing Power over Coax for the GMSL port
+
+required:
+ - compatible
+ - reg
+ - ports
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/media/video-interfaces.h>
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ deserializer@28 {
+ compatible = "maxim,max96714f";
+ reg = <0x28>;
+ powerdown-gpios = <&main_gpio0 37 GPIO_ACTIVE_LOW>;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port@0 {
+ reg = <0>;
+ max96714_gmsl_in: endpoint {
+ remote-endpoint = <&max96917f_gmsl_out>;
+ };
+ };
+
+ port@1 {
+ reg = <1>;
+ max96714_csi_out: endpoint {
+ bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
+ clock-lanes = <0>;
clock-lanes isn't listed in bindings. You can drop it from here.
Ok
+ data-lanes = <1 2 3 4>;
+ link-frequencies = /bits/ 64 <400000000>;
+ remote-endpoint = <&csi_in>;
+ };
+ };
+ };
+
+ i2c-gate {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ serializer@40 {
+ compatible = "maxim,max96717f";
+ reg = <0x40>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ #clock-cells = <0>;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ port@0 {
+ reg = <0>;
+ max96717f_csi_in: endpoint {
+ data-lanes = <1 2>;
+ lane-polarities = <1 0 1>;
Shouldn't lane-polarities be mentioned in bindings, too?
You are right I will add lane-polarities to my next patchset.
+ remote-endpoint = <&sensor_out>;
+ };
+ };
+
+ port@1 {
+ reg = <1>;
+ max96917f_gmsl_out: endpoint {
+ remote-endpoint = <&max96714_gmsl_in>;
+ };
+ };
+ };
+ };
+ };
+ };
+ };
+...
Best regards,
--
Julien Massot
Senior Software Engineer
Collabora Ltd.
Platinum Building, St John's Innovation Park, Cambridge CB4 0DS, UK
Registered in England & Wales, no. 5513718
