USB Type-C Specification defines a cable and connector for USB where
only one type of plug is supported on both ends, i.e. there will not
be Type-A plug on one end of the cable and Type-B plug on the other.
Determination of the host-to-device relationship happens through a
specific Configuration Channel (CC) which goes through the USB Type-C
cable. The Configuration Channel may also be used to detect optional
Accessory Modes - Analog Audio and Debug - and if USB Power Delivery
is supported, the Alternate Modes, where the connector is used for
something else then USB communication.

USB Power Delivery Specification defines a protocol that can be used
to negotiate the voltage and current levels with the connected
partners. USB Power Delivery allows higher voltages then the normal
5V, up to 20V, and current up to 5A over the cable. The USB Power
Delivery protocol is also used to negotiate the optional Alternate
Modes when they are supported. USB Power Delivery does not depend on
USB Type-C connector, however it is mostly used together with USB
Type-C connectors.

USB Type-C and USB Power Delivery Specifications define a set of state
machines that need to be implemented in either software or firmware.
Simple USB Type-C PHYs, for example USB Type-C Port Controller
Interface Specification compliant "Port Controllers" need the state
machines to be handled in the OS, but stand-alone USB Type-C and Power
Delivery controllers handle the state machines inside their firmware.
The USB Type-C and Power Delivery controllers usually function
autonomously, and do not necessarily require drivers.

Enable this configurations option if you have USB Type-C connectors on
your system and 1) you know your USB Type-C hardware requires OS
control (a driver) to function, or 2) if you need to be able to read
the status of the USB Type-C ports in your system, or 3) if you need
to be able to swap the power role (decide are you supplying or
consuming power over the cable) or data role (host or device) when
both roles are supported.

For more information, see the kernel documentation for USB Type-C
Connector Class API (Documentation/driver-api/usb/typec.rst)
<https://www.kernel.org/doc/html/latest/driver-api/usb/typec.html>
and ABI (Documentation/ABI/testing/sysfs-class-typec).

source code:

drivers/usb/typec/