usb: typec: tcpci: add attempt_vconn_swap_discovery callback

Add attempt_vconn_swap_discovery callback to determine whether the TCPM
should perform a Vconn swap following Discover Identity on SOP. The tcpci
will return false unless chip level drivers implement the callback.

Maxim based TCPCs will return true unless the last connection resulted in
a Vconn Over Current Fault, which may be the result of the Vconn swap. In
addition to the port resetting, the TCPCI will veto the next Vconn swap
from occurring.

Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240108191620.987785-21-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: maxim_contaminant: Implement check_contaminant callback

Maxim TCPC has additional ADCs and low current(1ua) current source
to measure the impedance of CC and SBU pins. When tcpm invokes
the check_contaminant callback, Maxim TCPC measures the impedance
of the CC & SBU pins and when the impedance measured is less than
1MOhm, it is assumed that USB-C port is contaminated. CC comparators
are also checked to differentiate between presence of sink and
contaminant. Once USB-C is deemed to be contaminated, MAXIM TCPC
has additional hardware to disable normal DRP toggling cycle and
enable 1ua on CC pins once every 2.4secs/4.8secs. Maxim TCPC
interrupts AP once the impedance on the CC pin is above the
1MOhm threshold. The Maxim tcpc driver then signals TCPM_PORT_CLEAN
to restart toggling.

Renaming tcpci_maxim.c to tcpci_maxim_core.c and moving reg read/write
helper functions to the tcpci_maxim.h header file.

Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230114093246.1933321-3-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>