Commit e0cc05d5 authored by Guan-Yu Lin's avatar Guan-Yu Lin Committed by Greg Kroah-Hartman
Browse files

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: default avatarGuan-Yu Lin <guanyulin@google.com>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231116083221.1201892-1-guanyulin@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 9768af12

drivers/usb/typec/tcpm/tcpm.c

+3 −3
Original line number Diff line number Diff line
@@ -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;

		}