Commits
Kyle Tso committed c710d0bb76f
usb: typec: tcpm: Extend the matching rules on PPS APDO selection Current matching rules ensure that the voltage range of selected Source Capability is entirely within the range defined in one of the Sink Capabilities. This is reasonable but not practical because Sink may not support wide range of voltage when sinking power while Source could advertise its capabilities in relatively wider range. For example, a Source PDO advertising 3.3V-11V@3A (9V Prog of Fixed Nominal Voltage) will not be selected if the Sink requires 5V-12V@3A PPS power. However, the Sink could work well if the requested voltage range in RDOs is 5V-11V@3A. Currently accepted: |--------- source -----| |----------- sink ---------------| Currently not accepted: |--------- source -----| |----------- sink ---------------| |--------- source -----| |----------- sink ---------------| |--------- source -----------------| |------ sink -------| To improve the usability, change the matching rules to what listed below: a. The Source PDO is selectable if any portion of the voltage range overlaps one of the Sink PDO's voltage range. b. The maximum operational voltage will be the lower one between the selected Source PDO and the matching Sink PDO. c. The maximum power will be the maximum operational voltage times the maximum current defined in the selected Source PDO d. Select the Source PDO with the highest maximum power Signed-off-by: Kyle Tso <kyletso@google.com> Acked-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>