At present, TCPM code assumes that local device supports
variable/batt pdos and always selects the pdo with highest
possible power within the board limit. This assumption
might not hold good for all devices. To overcome this,
this patch makes TCPM only accept a source_pdo when there is
a matching sink pdo.
For Fixed pdos: The voltage should match between the
incoming source_cap and the registered snk_pdo
For Variable/Batt pdos: The incoming source_cap voltage
range should fall within the registered snk_pdo's voltage
range.
Also, when the cap_mismatch bit is set, the max_power/current
should be set to the max_current/power of the sink_pdo.
This is according to:
"If the Capability Mismatch bit is set to one
The Maximum Operating Current/Power field may contain a value
larger than the maximum current/power offered in the Source
Capabilities message’s PDO as referenced by the Object position field.
This enables the Sink to indicate that it requires more current/power
than is being offered. If the Sink requires a different voltage this
will be indicated by its Sink Capabilities message.