On Thu, Jun 29, 2017 at 10:41 PM, Chen-Yu Tsai [off-list ref] wrote:

On Fri, Jun 30, 2017 at 5:19 AM, Rob Herring [off-list ref] wrote:

quoted

On Tue, Jun 27, 2017 at 07:07:34PM +0800, Yong Deng wrote:

quoted

Add binding documentation for Allwinner CSI.

For the subject:

dt-bindings: media: Add Allwinner Camera Sensor Interface (CSI)

"binding documentation" is redundant.

quoted

Signed-off-by: Yong Deng <yong.deng@magewell.com>
---
 .../devicetree/bindings/media/sunxi-csi.txt        | 51 ++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/sunxi-csi.txt

diff --git a/Documentation/devicetree/bindings/media/sunxi-csi.txt b/Documentation/devicetree/bindings/media/sunxi-csi.txt
new file mode 100644
index 0000000..770be0e
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/sunxi-csi.txt

@@ -0,0 +1,51 @@
+Allwinner V3s Camera Sensor Interface
+------------------------------
+
+Required properties:
+  - compatible: value must be "allwinner,sun8i-v3s-csi"
+  - reg: base address and size of the memory-mapped region.
+  - interrupts: interrupt associated to this IP
+  - clocks: phandles to the clocks feeding the CSI
+    * ahb: the CSI interface clock
+    * mod: the CSI module clock
+    * ram: the CSI DRAM clock
+  - clock-names: the clock names mentioned above
+  - resets: phandles to the reset line driving the CSI
+
+- ports: A ports node with endpoint definitions as defined in
+  Documentation/devicetree/bindings/media/video-interfaces.txt. The
+  first port should be the input endpoints, the second one the outputs

Is there more than one endpoint for each port? If so, need to define
that numbering too.

It is possible to have multiple camera sensors connected to the same
bus. Think front and back cameras on a cell phone or tablet.

I don't think any kind of numbering makes much sense though. The
system is free to use just one sensor at a time, or use many with
some time multiplexing scheme. What might matter to the end user
is where the camera is placed. But using the position or orientation
as a numbering scheme might not work well either. Someone may end
up using two sensors with the same orientation for stereoscopic
vision.

Well, for muxing, you need to no which endpoint is which mux input,
but if the muxing is at the board level, then that's really outside
this binding. For stereoscopic, don't you need both sensors to work at
the same time (i.e. not muxed). That would be multiple ports.

When would you have 2 output endpoints though? That could be to
different processing blocks, but those connections are internal,
fixed, and known. So you should document the numbering in that case.

Rob