usb: typec: intel_pmc_mux: Pass correct USB Type-C port number to SoC

The SoC expects the USB Type-C ports numbers to be starting with 0.
If the port number is passed as it is, the IOM status will not be
updated. The IOM port status check fails which will eventually
lead to PMC IPC communication failure.

Fixes: 43d596e3 ("usb: typec: intel_pmc_mux: Check the port status before connect")
Suggested-by: NUtkarsh Patel <utkarsh.h.patel@intel.com>
Signed-off-by: NAzhar Shaikh <azhar.shaikh@intel.com>
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200916091102.27118-3-heikki.krogerus@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/mux/intel_pmc_mux.c

@@ -148,8 +148,13 @@ struct pmc_usb {
 
 static void update_port_status(struct pmc_usb_port *port)
 {
+	u8 port_num;
+
+	/* SoC expects the USB Type-C port numbers to start with 0 */
+	port_num = port->usb3_port - 1;
+
 	port->iom_status = readl(port->pmc->iom_base + IOM_PORT_STATUS_OFFSET +
-				 port->usb3_port * sizeof(u32));
+				 port_num * sizeof(u32));
 }
 
 static int sbu_orientation(struct pmc_usb_port *port)