On Tue, Jul 14, 2020 at 01:36:14PM +0200, Hans de Goede wrote:

This commit adds the minimum bindings required to allow describing which
altmodes a port supports. Currently this is limited to just specifying:

1. The svid, which is the id of the altmode, e.g. displayport altmode has
a svid of 0xff01.

2. The vdo, a 32 bit integer, typically used as a bitmask describing the
capabilities of the altmode, the bits in the vdo are specified in the
specification of the altmode, the dt-binding simply refers to the
specification as that is the canonical source of the meaning of the bits.

What if this information should be derived from information already in 
DT (or would be there if alt mode connections are described)?

Later on we may want to extend the binding with extra properties specific
to some altmode, but for now this is sufficient to e.g. hook up
displayport alternate-mode.

I don't think this is sufficient as it doesn't describe how alternate 
modes are connected to various components. This has been discussed some 
here[1] with the CrOS folks. Maybe this is orthogonal, IDK, but I really 
need something that is somewhat complete and not sprinkle a few new 
properties at a time.

Signed-off-by: Hans de Goede <redacted>
---
Note I hope I got the yaml correct, this is my first time writing a
dt-binding in the new yaml style. I did run:
make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/connector/usb-connector.yaml
and that was happy.

That aspect of it looks fine.

Rob

[1] https://lkml.org/lkml/2020/4/22/1819