Commit 80137c18 authored by Kyle Tso's avatar Kyle Tso Committed by Greg Kroah-Hartman
Browse files

usb: typec: tcpm: Fix misuses of AMS invocation 



tcpm_ams_start is used to initiate an AMS as well as checking Collision
Avoidance conditions but not for flagging passive AMS (initiated by the
port partner). Fix the misuses of tcpm_ams_start in tcpm_pd_svdm.

ATTENTION doesn't need responses so the AMS flag is not needed here.

Fixes: 0bc3ee92 ("usb: typec: tcpm: Properly interrupt VDM AMS")
Signed-off-by: default avatarKyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210601123151.3441914-5-kyletso@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7ac50510

drivers/usb/typec/tcpm/tcpm.c

+5 −6
Original line number Diff line number Diff line
@@ -1555,7 +1555,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev, 
				svdm_version = PD_VDO_SVDM_VER(p[0]);

			}



			tcpm_ams_start(port, DISCOVER_IDENTITY);

			port->ams = DISCOVER_IDENTITY;

			/*

			 * PD2.0 Spec 6.10.3: respond with NAK as DFP (data host)

			 * PD3.1 Spec 6.4.4.2.5.1: respond with NAK if "invalid field" or
@@ -1576,19 +1576,18 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev, 
			}

			break;

		case CMD_DISCOVER_SVID:

			tcpm_ams_start(port, DISCOVER_SVIDS);

			port->ams = DISCOVER_SVIDS;

			break;

		case CMD_DISCOVER_MODES:

			tcpm_ams_start(port, DISCOVER_MODES);

			port->ams = DISCOVER_MODES;

			break;

		case CMD_ENTER_MODE:

			tcpm_ams_start(port, DFP_TO_UFP_ENTER_MODE);

			port->ams = DFP_TO_UFP_ENTER_MODE;

			break;

		case CMD_EXIT_MODE:

			tcpm_ams_start(port, DFP_TO_UFP_EXIT_MODE);

			port->ams = 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;