[PATCH v4 1/3] dt-bindings: media: atmel: csi2dc: add bindings for microchip csi2dc

From: Eugen Hristev
Date: Tue Nov 10 2020 - 10:11:49 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 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 | 144 ++++++++++++++++++
1 file changed, 144 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..967e8fefe363
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/microchip,csi2dc.yaml
@@ -0,0 +1,144 @@
+# 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.
+
+ 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 source pad with Synopsys 32-bit
+ IDI interface. The connected endpoint must be a IDI interface compatible
+ device (like Synopsys CSI2HOST) , that can provide 32-bit IDI interface
+ connection as sink pad.
+ For media entity and endpoints please refer to the bindings defined in
+ Documentation/devicetree/bindings/media/video-interfaces.txt.
+ For Synopsys IDI interface please refer to
+ Documentation/devicetree/bindings/media/snps,dw-csi-plat.txt
+
+ CSI2DC supports one 'port' node as sink pad with parallel interface. This is
+ called video pipe.
+ This port has an 'endpoint' can then be used as a source pad for another
+ controller (next in pipeline).
+ Please refer to the bindings defined in
+ Documentation/devicetree/bindings/media/video-interfaces.txt.
+
+ CSI2DC also supports direct access to the data through AHB, via DMA channel,
+ called data pipe.
+ Because of this, the sink 'port' child node (second) is not mandatory.
+ If the sink 'port' child node is missing, only data pipe is available.
+
+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
+
+ port@0:
+ type: object
+ description:
+ Input port node, single endpoint describing the input pad.
+
+ properties:
+ reg:
+ const: 0
+
+ endpoint:
+ type: object
+
+ properties:
+ remote-endpoint: true
+
+ required:
+ - remote-endpoint
+
+ additionalProperties: false
+
+ additionalProperties: false
+
+ port@1:
+ type: object
+ description:
+ Output port node, single endpoint, describing the output pad.
+
+ properties:
+ reg:
+ const: 1
+
+ endpoint:
+ type: object
+
+ properties:
+ remote-endpoint: true
+
+ required:
+ - remote-endpoint
+
+ additionalProperties: false
+
+ additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+ - port@0
+
+examples:
+ - |
+ csi2dc@e1404000 {
+ compatible = "microchip,sama7g5-csi2dc";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0xe1404000 0x500>;
+ clocks = <&pclk>, <&scck>;
+ clock-names = "pclk", "scck";
+
+ 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 */
+ };
+ };
+ };
+
+...
--
2.25.1