[PATCH v2 02/25] dt-bindings: media: atmel: csi2dc: add bindings for microchip csi2dc

From: Eugen Hristev
Date: Fri Nov 12 2021 - 09:27:08 EST


Add bindings documentation for Microchip CSI2 Demultiplexer controller.

CSI2DC is a demultiplexer from Synopsys IDI interface specification to
parallel interface connection or direct memory access.

Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
---
Changes in v2:
- changed the endpoint/port references as suggested by Rob

Changes in this version :
- fixed 'sink' name to be actually source.
- added dma properties and example with dma

Previous change log:
Changes in v5:
- modified bindings as per Rob Herring review

Changes in v4:
- Removed property for inter-line-delay and for clock continuous/non-continuous
- Removed virtual channel by reg for second endpoint

Changes in v3:
- Removed some text from description, as it was explained in the schema
- fixed other things as per Rob's review
- moved some text inside the schema, like the clock description

Changes in v2:
- fixed warnings reported by dt_binding_check

.../bindings/media/microchip,csi2dc.yaml | 159 ++++++++++++++++++
1 file changed, 159 insertions(+)
create mode 100644 Documentation/devicetree/bindings/media/microchip,csi2dc.yaml

diff --git a/Documentation/devicetree/bindings/media/microchip,csi2dc.yaml b/Documentation/devicetree/bindings/media/microchip,csi2dc.yaml
new file mode 100644
index 000000000000..45418c964bf3
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/microchip,csi2dc.yaml
@@ -0,0 +1,159 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/media/microchip,csi2dc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip CSI2 Demux Controller (CSI2DC)
+
+maintainers:
+ - Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
+
+description:
+ CSI2DC - Camera Serial Interface 2 Demux Controller
+
+ CSI2DC is a hardware block that receives incoming data from an IDI interface
+ and filters packets based on their data type and virtual channel identifier,
+ then converts the byte stream into a cross clock domain to a pixel stream
+ to a parallel interface that can be read by a sensor controller.
+ IDI interface is Synopsys proprietary.
+
+ CSI2DC provides two pipes, one video pipe and one data pipe. Video pipe
+ is connected to a sensor controller and the data pipe is accessible
+ as a DMA slave port to a DMA controller.
+
+ CSI2DC supports a single 'port' node as a sink port with Synopsys 32-bit
+ IDI interface. The connected endpoint must be a IDI interface compatible
+ device , that can provide 32-bit IDI interface connection as source port.
+ This port is mandatory.
+
+ CSI2DC supports one 'port' node as source port with parallel interface.
+ This is called video pipe.
+ This port has an 'endpoint' that can be connected to a sink port of another
+ controller (next in pipeline).
+
+ CSI2DC also supports direct access to the data through AHB, via DMA channel,
+ called data pipe.
+ Because of this, the source 'port' child node (second) is not mandatory.
+ If the source 'port' child node is missing, only data pipe is available.
+ For data pipe to be available, a dma controller must be referenced.
+
+properties:
+ compatible:
+ const: microchip,sama7g5-csi2dc
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 2
+
+ clock-names:
+ description:
+ CSI2DC must have two clocks to function correctly. One clock is the
+ peripheral clock for the inside functionality of the hardware block.
+ This is named 'pclk'. The second clock must be the cross domain clock,
+ in which CSI2DC will perform clock crossing. This clock must be fed
+ by the next controller in pipeline, which usually is a sensor controller.
+ Normally this clock should be given by this sensor controller who
+ is also a clock source. This clock is named 'scck', sensor controller clock.
+ items:
+ - const: pclk
+ - const: scck
+
+ dmas:
+ maxItems: 1
+
+ dma-names:
+ const: rx
+
+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ Input port node, single endpoint describing the input port.
+
+ properties:
+ endpoint:
+ $ref: video-interfaces.yaml#
+ unevaluatedProperties: false
+ description: Endpoint connected to input device
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ Output port node, single endpoint describing the output port.
+
+ properties:
+ endpoint:
+ unevaluatedProperties: false
+ $ref: video-interfaces.yaml#
+ description: Endpoint connected to output device
+
+ required:
+ - port@0
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+ - ports
+
+examples:
+ # Example for connecting to a parallel sensor controller block
+ - |
+ csi2dc@e1404000 {
+ compatible = "microchip,sama7g5-csi2dc";
+ reg = <0xe1404000 0x500>;
+ clocks = <&pclk>, <&scck>;
+ clock-names = "pclk", "scck";
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port@0 {
+ reg = <0>; /* must be 0, first child port */
+ csi2dc_in: endpoint { /* input from IDI interface */
+ remote-endpoint = <&csi2host_out>;
+ };
+ };
+
+ port@1 {
+ reg = <1>; /* must be 1, second child port */
+ csi2dc_out: endpoint {
+ remote-endpoint = <&xisc_in>; /* output to sensor controller */
+ };
+ };
+ };
+ };
+
+ # Example for connecting to a DMA master as an AHB slave
+ - |
+ #include <dt-bindings/dma/at91.h>
+ csi2dc@e1404000 {
+ compatible = "microchip,sama7g5-csi2dc";
+ reg = <0xe1404000 0x500>;
+ clocks = <&pclk>, <&scck>;
+ clock-names = "pclk", "scck";
+ dmas = <&dma0 AT91_XDMAC_DT_PERID(34)>;
+ dma-names = "rx";
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port@0 {
+ reg = <0>; /* must be 0, first child port */
+ csi2dc_input: endpoint { /* input from IDI interface */
+ remote-endpoint = <&csi2host_out>;
+ };
+ };
+ };
+ };
+
+...
--
2.25.1