usb-pd: send more request after wait

When we are not in an explicit contract, we still need to send more
requests attempts when we receive a WAIT control command. Otherwise,
the port partner can issue a hard reset.

BRANCH=none
BUG=b:117498337
TEST=hard reset boot loop goes away with this CL.

Change-Id: Iabe8f086659dc0d7a405fa9f17495fb1c61494cc
Signed-off-by: Jett Rink <jettrink@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1289311
Commit-Ready: Edward Hill <ecgh@chromium.org>
Reviewed-by: Edward Hill <ecgh@chromium.org>

1 files changed, 35 insertions, 37 deletions

diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index e9e86be32b..988443aba1 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -1381,6 +1381,7 @@ static void handle_data_request(int port, uint16_t head,
 	case PD_DATA_SOURCE_CAP:
 		if ((pd[port].task_state == PD_STATE_SNK_DISCOVERY)
 			|| (pd[port].task_state == PD_STATE_SNK_TRANSITION)
+			|| (pd[port].task_state == PD_STATE_SNK_REQUESTED)
 #ifdef CONFIG_USB_PD_VBUS_DETECT_NONE
 			|| (pd[port].task_state ==
 			    PD_STATE_SNK_HARD_RESET_RECOVER)
@@ -1650,49 +1651,46 @@ static void handle_ctrl_request(int port, uint16_t head,
 			set_state(port, PD_STATE_SNK_READY);
 		else if (pd[port].task_state == PD_STATE_SNK_REQUESTED) {
 			/*
-			 * Explicit Contract in place
+			 * On reception of a WAIT message, transition to
+			 * PD_STATE_SNK_READY after PD_T_SINK_REQUEST ms to
+			 * send another request.
 			 *
-			 *  On reception of a WAIT message, transition to
-			 *  PD_STATE_SNK_READY after PD_T_SINK_REQUEST ms to
-			 *  send another reqest.
+			 * On reception of a REJECT message, transition to
+			 * PD_STATE_SNK_READY but don't resend the request if
+			 * we already have a contract in place.
 			 *
-			 *  On reception of a REJECT messag, transition to
-			 *  PD_STATE_SNK_READY but don't resend the request.
-			 *
-			 * NO Explicit Contract in place
-			 *
-			 *  On reception of a WAIT or REJECT message,
-			 *  transition to PD_STATE_SNK_DISCOVERY
+			 * On reception of a REJECT message without a contract,
+			 * transition to PD_STATE_SNK_DISCOVERY instead.
 			 */
-			if (pd[port].flags & PD_FLAGS_EXPLICIT_CONTRACT) {
-				/* We have an explicit contract */
-				if (type == PD_CTRL_WAIT) {
-					/*
-					 * Trigger a new power request when
-					 * we enter PD_STATE_SNK_READY
-					 */
-					pd[port].new_power_request = 1;
+			if (type == PD_CTRL_WAIT) {
+				/*
+				 * Trigger a new power request when
+				 * we enter PD_STATE_SNK_READY
+				 */
+				pd[port].new_power_request = 1;
 
-					/*
-					 * After the request is triggered,
-					 * make sure the request is sent.
-					 */
-					pd[port].prev_request_mv = 0;
+				/*
+				 * After the request is triggered,
+				 * make sure the request is sent.
+				 */
+				pd[port].prev_request_mv = 0;
 
-					/*
-					 * Transition to PD_STATE_SNK_READY
-					 * after PD_T_SINK_REQUEST ms.
-					 */
-					set_state_timeout(port, get_time().val +
-							PD_T_SINK_REQUEST,
-							PD_STATE_SNK_READY);
-				} else {
-					/* The request was rejected */
-					set_state(port, PD_STATE_SNK_READY);
-				}
+				/*
+				 * Transition to PD_STATE_SNK_READY
+				 * after PD_T_SINK_REQUEST ms.
+				 */
+				set_state_timeout(port,
+						  get_time().val +
+							  PD_T_SINK_REQUEST,
+						  PD_STATE_SNK_READY);
 			} else {
-				/* No explicit contract */
-				set_state(port, PD_STATE_SNK_DISCOVERY);
+				/* The request was rejected */
+				const int in_contract =
+					pd[port].flags &
+					PD_FLAGS_EXPLICIT_CONTRACT;
+				set_state(port,
+					  in_contract ? PD_STATE_SNK_READY
+						      : PD_STATE_SNK_DISCOVERY);
 			}
 		}
 #endif