This also introduces a new class, `USBConfiguration` that stores a
configuration. The device, when instructed, sets this configuration and
holds a pointer to it so we have a record of what configuration is
currently active.
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.
Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
And also try_create<T> => try_make_ref_counted<T>.
A global "create" was a bit much. The new name matches make<T> better,
which we've used for making single-owner objects since forever.
A hub can technically have up to 255 ports, given that bNbrPorts is a
u8 and the DeviceRemovable field is a VLA to support up to 255 ports.
Source: USB 2.0 Specification Section 11.23.2.1
That means this enum is not going to scale well in terms of size.
Replacing it with a raw u8 allows me to remove the two port assumption
and a cast.
This removes Pipes dependency on the UHCIController by introducing a
controller base class. This will be used to implement other controllers
such as OHCI.
Additionally, there can be multiple instances of a UHCI controller.
For example, multiple UHCI instances can be required for systems with
EHCI controllers. EHCI relies on using multiple of either UHCI or OHCI
controllers to drive USB 1.x devices.
This means UHCIController can no longer be a singleton. Multiple
instances of it can now be created and passed to the device and then to
the pipe.
To handle finding and creating these instances, USBManagement has been
introduced. It has the same pattern as the other management classes
such as NetworkManagement.