Allows drivers to define more fine grained features for devices, not
strictly depending on assumptions we can make depending on the
implemented vfuncs.
We keep this per class but could be in theory moved to each instance.
In any case, added an utility function to initialize it in the way we
can ensure that we've a consistent way for setting them across all the
devices.
Each command should be separated by SLEEP to be considered as something
we want to perform during the current operation, otherwise will be used
by next operation consuming it.
In case we sent a sleep event to the device we may want to wait it to
emit the finger needed state before the timeout is completed.
So add a function to manage this for all the scan cases
There are two variants one with storage and identify support and the
other without storage.
It implements the following commands:
* INSERT id
* REMOVE id
* SCAN id
* ERROR error-code
* LIST (returns saved print)
The INSERT/REMOVE/LIST commands are only available in the storage
driver. The SCAN command emulates presenting a finger.
These commands can be send ahead of time, and will be queued and
processed when appropriate. i.e. for INSERT/REMOVE that is immediately
when possible, for SCAN/ERROR processing is delayed.
The LIST command is always processed immediately.
Note that only a single command can be send per socket connection and
the command must be send in a single message. The socket will be closed
after the command has been processed.
Co-authored-by: Bastien Nocera <hadess@hadess.net>
Co-authored-by: Marco Trevisan (Treviño) <mail@3v1n0.net>
