[v3,06/15] dt-bindings: media: sun6i-a31-csi: Add MIPI CSI-2 input port

Commit Message

Paul Kocialkowski Dec. 11, 2020, 3:56 p.m. UTC

The A31 CSI controller supports two distinct input interfaces:
parallel and an external MIPI CSI-2 bridge. The parallel interface
is often connected to a set of hardware pins while the MIPI CSI-2
bridge is an internal FIFO-ish link. As a result, these two inputs
are distinguished as two different ports.

Note that only one of the two may be present on a controller instance.
For example, the V3s has one controller dedicated to MIPI-CSI2 and one
dedicated to parallel.

Update the binding with an explicit ports node that holds two distinct
port nodes: one for parallel input and one for MIPI CSI-2.

This is backward-compatible with the single-port approach that was
previously taken for representing the parallel interface port, which
stays enumerated as fwnode port 0.

Note that additional ports may be added in the future, especially to
support feeding the CSI controller's output to the ISP.

Signed-off-by: Paul Kocialkowski <[e-mail]>
---
 .../media/allwinner,sun6i-a31-csi.yaml        | 88 ++++++++++++++++---
 1 file changed, 75 insertions(+), 13 deletions(-)

Comments

Rob Herring Dec. 14, 2020, 11:12 p.m. UTC | #1

On Fri, 11 Dec 2020 16:56:59 +0100, Paul Kocialkowski wrote:
> The A31 CSI controller supports two distinct input interfaces:
> parallel and an external MIPI CSI-2 bridge. The parallel interface
> is often connected to a set of hardware pins while the MIPI CSI-2
> bridge is an internal FIFO-ish link. As a result, these two inputs
> are distinguished as two different ports.
> 
> Note that only one of the two may be present on a controller instance.
> For example, the V3s has one controller dedicated to MIPI-CSI2 and one
> dedicated to parallel.
> 
> Update the binding with an explicit ports node that holds two distinct
> port nodes: one for parallel input and one for MIPI CSI-2.
> 
> This is backward-compatible with the single-port approach that was
> previously taken for representing the parallel interface port, which
> stays enumerated as fwnode port 0.
> 
> Note that additional ports may be added in the future, especially to
> support feeding the CSI controller's output to the ISP.
> 
> Signed-off-by: Paul Kocialkowski <[e-mail]>
> ---
>  .../media/allwinner,sun6i-a31-csi.yaml        | 88 ++++++++++++++++---
>  1 file changed, 75 insertions(+), 13 deletions(-)
> 

Reviewed-by: Rob Herring <[e-mail]>

Though, it may need updating to use video-interfaces and graph 
schemas[1] depending what lands first.

[1] https://lore.kernel.org/linux-devicetree/[e-mail]/

Patch

diff --git a/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml b/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
index 1fd9b5532a21..77ded77505e9 100644
--- a/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
+++ b/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
@@ -67,6 +67,62 @@  properties:
 
     additionalProperties: false
 
+  ports:
+    type: object
+
+    properties:
+      port@0:
+        type: object
+        description: Parallel input port, connect to a parallel sensor
+
+        properties:
+          reg:
+            const: 0
+
+          endpoint:
+            type: object
+
+            properties:
+              remote-endpoint: true
+
+              bus-width:
+                enum: [ 8, 10, 12, 16 ]
+
+              pclk-sample: true
+              hsync-active: true
+              vsync-active: true
+
+            required:
+              - bus-width
+              - remote-endpoint
+
+        required:
+          - endpoint
+
+        additionalProperties: false
+
+      port@1:
+        type: object
+        description: MIPI CSI-2 bridge input port
+
+        properties:
+          reg:
+            const: 1
+
+          endpoint:
+            type: object
+
+            properties:
+              remote-endpoint: true
+
+            required:
+              - remote-endpoint
+
+        required:
+          - endpoint
+
+        additionalProperties: false
+
 required:
   - compatible
   - reg
@@ -95,19 +151,25 @@  examples:
                       "ram";
         resets = <&ccu RST_BUS_CSI>;
 
-        port {
-            /* Parallel bus endpoint */
-            csi1_ep: endpoint {
-                remote-endpoint = <&adv7611_ep>;
-                bus-width = <16>;
-
-                /*
-                 * If hsync-active/vsync-active are missing,
-                 * embedded BT.656 sync is used.
-                 */
-                 hsync-active = <0>; /* Active low */
-                 vsync-active = <0>; /* Active low */
-                 pclk-sample = <1>;  /* Rising */
+        ports {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            port@0 {
+                reg = <0>;
+                /* Parallel bus endpoint */
+                csi1_ep: endpoint {
+                    remote-endpoint = <&adv7611_ep>;
+                    bus-width = <16>;
+
+                    /*
+                     * If hsync-active/vsync-active are missing,
+                     * embedded BT.656 sync is used.
+                     */
+                     hsync-active = <0>; /* Active low */
+                     vsync-active = <0>; /* Active low */
+                     pclk-sample = <1>;  /* Rising */
+                };
             };
         };
     };