usb: typec: tcpm: skip checking port->send_discover in PD3.0

The original Collison Avoidance mechanism, port->send_discover, avoids
the conflict when port partners start AMS almost the same time. However,
this mechanism is replaced by SINK_TX_OK and SINK_TX_NG. Skip the check
in PD3.0 to avoid the deadlock when source is requesting DR_SWAP where
sink is requesting DISCOVER_IDENTITY.

Signed-off-by: Guan-Yu Lin <guanyulin@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231116083221.1201892-1-guanyulin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 058d5b853b5749d0b9743554380ccaf7880c75c0..ff3c171a3a75e3f37f5cd08997565116409279c3 100644 (file)
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -2847,7 +2847,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
                                           PD_MSG_CTRL_NOT_SUPP,
                                           NONE_AMS);
                } else {
-                       if (port->send_discover) {
+                       if (port->send_discover && port->negotiated_rev < PD_REV30) {
                                tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
                                break;
                        }
@@ -2863,7 +2863,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
                                           PD_MSG_CTRL_NOT_SUPP,
                                           NONE_AMS);
                } else {
-                       if (port->send_discover) {
+                       if (port->send_discover && port->negotiated_rev < PD_REV30) {
                                tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
                                break;
                        }
@@ -2872,7 +2872,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
                }
                break;
        case PD_CTRL_VCONN_SWAP:
-               if (port->send_discover) {
+               if (port->send_discover && port->negotiated_rev < PD_REV30) {
                        tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
                        break;
                }