Commit 063933f4 authored by Kyle Tso's avatar Kyle Tso Committed by Greg Kroah-Hartman
Browse files

usb: typec: tcpm: Properly handle Alert and Status Messages 



When receiving Alert Message, if it is not unexpected but is
unsupported for some reason, the port should return Not_Supported
Message response.

Also, according to PD3.0 Spec 6.5.2.1.4 Event Flags Field, the
OTP/OVP/OCP flags in the Event Flags field in Status Message no longer
require Get_PPS_Status Message to clear them. Thus remove it when
receiving Status Message with those flags being set.

In addition, add the missing AMS operations for Status Message.

Fixes: 64f7c494 ("typec: tcpm: Add support for sink PPS related messages")
Fixes: 0908c5ac ("usb: typec: tcpm: AMS and Collision Avoidance")
Signed-off-by: default avatarKyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210531164928.2368606-1-kyletso@google.com


Cc: stable <stable@vger.kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4d2aa178

drivers/usb/typec/tcpm/tcpm.c

+27 −25
Original line number Diff line number Diff line
@@ -2188,20 +2188,25 @@ static void tcpm_handle_alert(struct tcpm_port *port, const __le32 *payload, 


	if (!type) {

		tcpm_log(port, "Alert message received with no type");

		tcpm_queue_message(port, PD_MSG_CTRL_NOT_SUPP);

		return;

	}



	/* Just handling non-battery alerts for now */

	if (!(type & USB_PD_ADO_TYPE_BATT_STATUS_CHANGE)) {

		switch (port->state) {

		case SRC_READY:

		case SNK_READY:

		if (port->pwr_role == TYPEC_SOURCE) {

			port->upcoming_state = GET_STATUS_SEND;

			tcpm_ams_start(port, GETTING_SOURCE_SINK_STATUS);

		} else {

			/*

			 * Do not check SinkTxOk here in case the Source doesn't set its Rp to

			 * SinkTxOk in time.

			 */

			port->ams = GETTING_SOURCE_SINK_STATUS;

			tcpm_set_state(port, GET_STATUS_SEND, 0);

			break;

		default:

			tcpm_queue_message(port, PD_MSG_CTRL_WAIT);

			break;

		}

	} else {

		tcpm_queue_message(port, PD_MSG_CTRL_NOT_SUPP);

	}

}
@@ -2445,6 +2450,11 @@ static void tcpm_pd_data_request(struct tcpm_port *port, 
		tcpm_pd_handle_state(port, BIST_RX, BIST, 0);

		break;

	case PD_DATA_ALERT:

		if (port->state != SRC_READY && port->state != SNK_READY)

			tcpm_pd_handle_state(port, port->pwr_role == TYPEC_SOURCE ?

					     SRC_SOFT_RESET_WAIT_SNK_TX : SNK_SOFT_RESET,

					     NONE_AMS, 0);

		else

			tcpm_handle_alert(port, msg->payload, cnt);

		break;

	case PD_DATA_BATT_STATUS:
@@ -2769,24 +2779,16 @@ static void tcpm_pd_ext_msg_request(struct tcpm_port *port, 


	switch (type) {

	case PD_EXT_STATUS:

		/*

		 * If PPS related events raised then get PPS status to clear

		 * (see USB PD 3.0 Spec, 6.5.2.4)

		 */

		if (msg->ext_msg.data[USB_PD_EXT_SDB_EVENT_FLAGS] &

		    USB_PD_EXT_SDB_PPS_EVENTS)

			tcpm_pd_handle_state(port, GET_PPS_STATUS_SEND,

					     GETTING_SOURCE_SINK_STATUS, 0);



		else

			tcpm_pd_handle_state(port, ready_state(port), NONE_AMS, 0);

		break;

	case PD_EXT_PPS_STATUS:

		/*

		 * For now the PPS status message is used to clear events

		 * and nothing more.

		 */

		tcpm_pd_handle_state(port, ready_state(port), NONE_AMS, 0);

		if (port->ams == GETTING_SOURCE_SINK_STATUS) {

			tcpm_ams_finish(port);

			tcpm_set_state(port, ready_state(port), 0);

		} else {

			/* unexpected Status or PPS_Status Message */

			tcpm_pd_handle_state(port, port->pwr_role == TYPEC_SOURCE ?

					     SRC_SOFT_RESET_WAIT_SNK_TX : SNK_SOFT_RESET,

					     NONE_AMS, 0);

		}

		break;

	case PD_EXT_SOURCE_CAP_EXT:

	case PD_EXT_GET_BATT_CAP:

include/linux/usb/pd_ext_sdb.h

+0 −4
Original line number Diff line number Diff line
@@ -24,8 +24,4 @@ enum usb_pd_ext_sdb_fields { 
#define USB_PD_EXT_SDB_EVENT_OVP		BIT(3)

#define USB_PD_EXT_SDB_EVENT_CF_CV_MODE		BIT(4)



#define USB_PD_EXT_SDB_PPS_EVENTS	(USB_PD_EXT_SDB_EVENT_OCP |	\

					 USB_PD_EXT_SDB_EVENT_OTP |	\

					 USB_PD_EXT_SDB_EVENT_OVP)



#endif /* __LINUX_USB_PD_EXT_SDB_H */