Commit 0bc3ee92 authored by Kyle Tso's avatar Kyle Tso Committed by Greg Kroah-Hartman
Browse files

usb: typec: tcpm: Properly interrupt VDM AMS 



When a VDM AMS is interrupted by Messages other than VDM, the AMS needs
to be finished properly. Also start a VDM AMS if receiving SVDM Commands
from the port partner to complement the functionality of tcpm_vdm_ams().

Fixes: 0908c5ac ("usb: typec: tcpm: AMS and Collision Avoidance")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Acked-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarKyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210523015855.1785484-2-kyletso@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2cbd838e

drivers/usb/typec/tcpm/tcpm.c

+30 −0
Original line number Diff line number Diff line
@@ -1550,6 +1550,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev, 
			if (PD_VDO_SVDM_VER(p[0]) < svdm_version)

				typec_partner_set_svdm_version(port->partner,

							       PD_VDO_SVDM_VER(p[0]));



			tcpm_ams_start(port, DISCOVER_IDENTITY);

			/* 6.4.4.3.1: Only respond as UFP (device) */

			if (port->data_role == TYPEC_DEVICE &&

			    port->nr_snk_vdo) {
@@ -1568,14 +1570,19 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev, 
			}

			break;

		case CMD_DISCOVER_SVID:

			tcpm_ams_start(port, DISCOVER_SVIDS);

			break;

		case CMD_DISCOVER_MODES:

			tcpm_ams_start(port, DISCOVER_MODES);

			break;

		case CMD_ENTER_MODE:

			tcpm_ams_start(port, DFP_TO_UFP_ENTER_MODE);

			break;

		case CMD_EXIT_MODE:

			tcpm_ams_start(port, DFP_TO_UFP_EXIT_MODE);

			break;

		case CMD_ATTENTION:

			tcpm_ams_start(port, ATTENTION);

			/* Attention command does not have response */

			*adev_action = ADEV_ATTENTION;

			return 0;
@@ -2287,6 +2294,12 @@ static void tcpm_pd_data_request(struct tcpm_port *port, 
	bool frs_enable;

	int ret;



	if (tcpm_vdm_ams(port) && type != PD_DATA_VENDOR_DEF) {

		port->vdm_state = VDM_STATE_ERR_BUSY;

		tcpm_ams_finish(port);

		mod_vdm_delayed_work(port, 0);

	}



	switch (type) {

	case PD_DATA_SOURCE_CAP:

		for (i = 0; i < cnt; i++)
@@ -2459,6 +2472,16 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, 
	enum pd_ctrl_msg_type type = pd_header_type_le(msg->header);

	enum tcpm_state next_state;



	/*

	 * Stop VDM state machine if interrupted by other Messages while NOT_SUPP is allowed in

	 * VDM AMS if waiting for VDM responses and will be handled later.

	 */

	if (tcpm_vdm_ams(port) && type != PD_CTRL_NOT_SUPP && type != PD_CTRL_GOOD_CRC) {

		port->vdm_state = VDM_STATE_ERR_BUSY;

		tcpm_ams_finish(port);

		mod_vdm_delayed_work(port, 0);

	}



	switch (type) {

	case PD_CTRL_GOOD_CRC:

	case PD_CTRL_PING:
@@ -2717,6 +2740,13 @@ static void tcpm_pd_ext_msg_request(struct tcpm_port *port, 
	enum pd_ext_msg_type type = pd_header_type_le(msg->header);

	unsigned int data_size = pd_ext_header_data_size_le(msg->ext_msg.header);



	/* stopping VDM state machine if interrupted by other Messages */

	if (tcpm_vdm_ams(port)) {

		port->vdm_state = VDM_STATE_ERR_BUSY;

		tcpm_ams_finish(port);

		mod_vdm_delayed_work(port, 0);

	}



	if (!(le16_to_cpu(msg->ext_msg.header) & PD_EXT_HDR_CHUNKED)) {

		tcpm_pd_handle_msg(port, PD_MSG_CTRL_NOT_SUPP, NONE_AMS);

		tcpm_log(port, "Unchunked extended messages unsupported");