Add generic Type-C "port manager" support

[raveslave]

Add support for USB Type-C controllers with PD

This is useful when designing products using USB-C connectors needing additional support like higher current, role-switching "host/device", power source/sink or simply supporting vendor packages over PD (using the CC pins).

The driver should implement support for

• DRP (DFP/UFP), i.e. the type-c terms for "OTG", with low amount of programmability.
• PD 2.0 / 3.0 to support source or sink, incl providing or negotiating power-requirements (voltage/current) with PD-compliant power-supplies or computers using Type-C.
• Alternate mode(s)

The driver should basically serve as a state machine that orchestrates connection-events, data and power roles as well as runtime changes like role-swap or power-updates.

The connection between the TCPM (running in Zephyr) and the TCPC (vendor IC) is defined as the USB Type-C Port Controller Interface, TCPCI. see: https://www.usb.org/document-library/usb-type-cr-port-controller-interface-specification

Event and control needs

The low level driver should be responsible for

• Reporting VBUS status and activating VBUS
• Setting CC lines and providing CC line status
• Setting line polarity
• Activating and deactivating VCONN
• Setting current limits
• Activating and deactivating PD message transfers
• Sending and receiving PD messages
• wip...

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[keith-zephyr]

Google is in the planning process of upstreaming the USB-C stack used on Chromebooks into Zephyr.

The is a bit of work needed to reorganize the code to conform to Zephyr's structure, so if anyone has specific features like would like prioritized, please add a comment to this issue.

[dzarda]

@keith-zephyr That's a nice bit of news. Last time I checked there was no Sink-only support in the Chrome EC codebase. However that's a major case for Zephyr devices. Would that be available?

[keith-zephyr]

Yes, we plan to provide source-only, sink-only, and dual-role port operation. We also support try source and try sink operation for dual-role ports.

[keith-zephyr]

This github issue has been created that will cover the work of moving Google's USB-C stack to Zephyr. We welcome comments and suggestions.