TCPMv2: Store Tx type in PE state

This will be used for VDM request state for discovery. Also change
names of identity discovery timer and counter fields to comport with PD
spec.

This is substantially based on https://crrev.com/c/2148427.

BUG=none
TEST=make buildall
BRANCH=none

Change-Id: Iabda5c4cd169944a6c84bc72f551de7eb82ab424
Signed-off-by: Abe Levkoy <alevkoy@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2174463
Reviewed-by: Diana Z <dzigterman@chromium.org>

5 files changed, 49 insertions, 43 deletions

diff --git a/common/usb_pd_alt_mode_dfp.c b/common/usb_pd_alt_mode_dfp.c
index 3ec48fa213..715dc9b995 100644
--- a/common/usb_pd_alt_mode_dfp.c
+++ b/common/usb_pd_alt_mode_dfp.c
@@ -510,6 +510,10 @@ enum idh_ptype get_usb_pd_cable_type(int port)
 	return cable->type;
 }
 
+/*
+ * TODO(b/152417597): Support SOP and SOP'; eliminate redundant code for port
+ * partner and cable identity discovery.
+ */
 void dfp_consume_cable_response(int port, int cnt, uint32_t *payload,
 				uint16_t head)
 {
@@ -547,7 +551,6 @@ void dfp_consume_cable_response(int port, int cnt, uint32_t *payload,
 					payload[VDO_INDEX_PTYPE_CABLE2];
 
 		cable->is_identified = 1;
-		cable->discovery = PD_DISC_COMPLETE;
 	}
 }
 
diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c
index 51ed5113da..d3e0d40617 100644
--- a/common/usb_pd_policy.c
+++ b/common/usb_pd_policy.c
@@ -899,7 +899,7 @@ int pd_svdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload,
 			if (is_transmit_msg_sop_prime(port)) {
 				/* Store cable type */
 				dfp_consume_cable_response(port, cnt, payload,
-							head);
+						       head);
 
 				/*
 				 * Enter USB4 mode if the cable supports USB4
diff --git a/common/usbc/usb_pe_drp_sm.c b/common/usbc/usb_pe_drp_sm.c
index 7f6d81adcd..4f80eb72f4 100644
--- a/common/usbc/usb_pe_drp_sm.c
+++ b/common/usbc/usb_pe_drp_sm.c
@@ -380,9 +380,12 @@ static struct policy_engine {
 	/* PD_VDO_INVALID is used when there is an invalid VDO */
 	int32_t ama_vdo;
 	int32_t vpd_vdo;
-	/* alternate mode discovery results */
+	/* Alternate mode discovery results */
 	struct pd_discovery discovery;
 
+	/* Partner type to send */
+	enum tcpm_transmit_type tx_type;
+
 	/* VDM - used to send information to shared VDM Request state */
 	/* TODO(b/150611251): Remove when all VDMs use shared parent */
 	enum port_partner partner_type;
@@ -424,7 +427,7 @@ static struct policy_engine {
 	 * This timer is used during an Explicit Contract when discovering
 	 * whether a Port Partner is PD Capable using SOP'.
 	 */
-	uint64_t discover_port_identity_timer;
+	uint64_t discover_identity_timer;
 
 	/*
 	 * This timer is used in a Source to ensure that the Sink has had
@@ -511,7 +514,7 @@ static struct policy_engine {
 	 * nDiscoverIdentityCount, the port shall not send any further
 	 * SOP'/SOP'' messages.
 	 */
-	uint32_t discover_port_identity_counter;
+	uint32_t discover_identity_counter;
 	/*
 	 * For PD2.0, we need to be a DFP before sending a discovery identity
 	 * message to our port partner. This counter keeps track of how
@@ -561,6 +564,7 @@ static void pe_init(int port)
 	pe[port].source_cap_timer = TIMER_DISABLED;
 	pe[port].no_response_timer = TIMER_DISABLED;
 	pe[port].data_role = pd_get_data_role(port);
+	pe[port].tx_type = TCPC_TX_INVALID;
 
 	tc_pd_connection(port, 0);
 
@@ -996,8 +1000,8 @@ static bool common_src_snk_dpm_requests(int port)
 			PE_CLR_FLAG(port, PE_FLAGS_DISCOVER_PORT_IDENTITY_DONE);
 			pd_dfp_discovery_init(port);
 			pe[port].dr_swap_attempt_counter = 0;
-			pe[port].discover_port_identity_counter = 0;
-			pe[port].discover_port_identity_timer = get_time().val +
+			pe[port].discover_identity_counter = 0;
+			pe[port].discover_identity_timer = get_time().val +
 						PD_T_DISCOVER_IDENTITY;
 		}
 		return true;
@@ -1191,7 +1195,7 @@ static bool pe_attempt_port_discovery(int port)
 	/* If mode entry was successful, disable the timer */
 	if (PE_CHK_FLAG(port, PE_FLAGS_MODAL_OPERATION)) {
 		PE_SET_FLAG(port, PE_FLAGS_DISCOVER_PORT_IDENTITY_DONE);
-		pe[port].discover_port_identity_timer = TIMER_DISABLED;
+		pe[port].discover_identity_timer = TIMER_DISABLED;
 		return false;
 	}
 
@@ -1199,9 +1203,9 @@ static bool pe_attempt_port_discovery(int port)
 	 * Run discovery functions when the timer indicating either cable
 	 * discovery spacing or BUSY spacing runs out.
 	 */
-	if (get_time().val > pe[port].discover_port_identity_timer) {
-		if (pe[port].cable.discovery == PD_DISC_NEEDED &&
-		    pe_can_send_sop_prime(port)) {
+	if (get_time().val > pe[port].discover_identity_timer) {
+		if (pd_get_identity_discovery(port, TCPC_TX_SOP_PRIME) ==
+		    PD_DISC_NEEDED && pe_can_send_sop_prime(port)) {
 			PE_SET_FLAG(port, PE_FLAGS_LOCALLY_INITIATED_AMS);
 			set_state_pe(port, PE_VDM_IDENTITY_REQUEST_CBL);
 			return true;
@@ -1334,14 +1338,14 @@ static void pe_src_startup_entry(int port)
 		 * src_discovery for the first time.  After initial startup
 		 * set, vdm_identity_request_cbl will handle the timer updates.
 		 */
-		pe[port].discover_port_identity_timer = get_time().val;
+		pe[port].discover_identity_timer = get_time().val;
 
 		/* Clear port discovery flags */
 		PE_CLR_FLAG(port, PE_FLAGS_DISCOVER_PORT_IDENTITY_DONE);
 		pd_dfp_discovery_init(port);
 		pe[port].ama_vdo = PD_VDO_INVALID;
 		pe[port].vpd_vdo = PD_VDO_INVALID;
-		pe[port].discover_port_identity_counter = 0;
+		pe[port].discover_identity_counter = 0;
 		memset(&pe[port].cable, 0, sizeof(struct pd_cable));
 
 		/* Reset dr swap attempt counter */
@@ -1413,9 +1417,9 @@ static void pe_src_discovery_run(int port)
 	 * contract, we use it here to ensure we space any potential BUSY
 	 * requests properly.
 	 */
-	if (pe[port].cable.discovery == PD_DISC_NEEDED &&
-	    get_time().val > pe[port].discover_port_identity_timer &&
-	    pe_can_send_sop_prime(port)) {
+	if (pd_get_identity_discovery(port, TCPC_TX_SOP_PRIME) == PD_DISC_NEEDED
+			&& get_time().val > pe[port].discover_identity_timer
+			&& pe_can_send_sop_prime(port)) {
 		set_state_pe(port, PE_VDM_IDENTITY_REQUEST_CBL);
 		return;
 	}
@@ -2116,12 +2120,12 @@ static void pe_snk_startup_entry(int port)
 		 * Set DiscoverIdentityTimer to trigger when we enter
 		 * snk_ready for the first time.
 		 */
-		pe[port].discover_port_identity_timer = get_time().val;
+		pe[port].discover_identity_timer = get_time().val;
 
 		/* Clear port discovery flags */
 		PE_CLR_FLAG(port, PE_FLAGS_DISCOVER_PORT_IDENTITY_DONE);
 		pd_dfp_discovery_init(port);
-		pe[port].discover_port_identity_counter = 0;
+		pe[port].discover_identity_counter = 0;
 		memset(&pe[port].cable, 0, sizeof(struct pd_cable));
 
 		/* Reset dr swap attempt counter */
@@ -4124,14 +4128,14 @@ static void pe_vdm_identity_request_cbl_entry(int port)
 
 	print_current_state(port);
 
-	msg[0] = VDO(USB_SID_PD, 1, VDO_SVDM_VERS(pd_get_vdo_ver(port,
-							   TCPC_TX_SOP_PRIME)) |
-		     DISCOVER_IDENTITY);
+	msg[0] = VDO(USB_SID_PD, 1,
+			VDO_SVDM_VERS(pd_get_vdo_ver(port, TCPC_TX_SOP_PRIME)) |
+			DISCOVER_IDENTITY);
 	tx_emsg[port].len = sizeof(uint32_t);
 
 	prl_send_data_msg(port, TCPC_TX_SOP_PRIME, PD_DATA_VENDOR_DEF);
 
-	pe[port].discover_port_identity_counter++;
+	pe[port].discover_identity_counter++;
 }
 
 static void pe_vdm_identity_request_cbl_run(int port)
@@ -4177,7 +4181,7 @@ static void pe_vdm_identity_request_cbl_run(int port)
 				 * during an Explicit Contract
 				 */
 				if (prl_get_rev(port, TCPC_TX_SOP) != PD_REV20)
-					prl_set_rev(port, TCPC_TX_SOP_PRIME,
+					prl_set_rev(port, sop,
 							pe[port].cable.rev);
 
 			} else if (PD_VDO_CMDT(payload[0]) == CMDT_RSP_NAK) {
@@ -4185,7 +4189,8 @@ static void pe_vdm_identity_request_cbl_run(int port)
 				 * PE_SRC_VDM_Identity_NAKed and
 				 * PE_INIT_PORT_VDM_Identity_NAKed embedded here
 				 */
-				pe[port].cable.discovery = PD_DISC_FAIL;
+				pd_set_identity_discovery(port, sop,
+						PD_DISC_FAIL);
 			} else if (PD_VDO_CMDT(payload[0]) == CMDT_RSP_BUSY) {
 				/*
 				 * Don't fill in the discovery field so we
@@ -4193,14 +4198,15 @@ static void pe_vdm_identity_request_cbl_run(int port)
 				 */
 				CPRINTS("C%d: Cable Busy, DiscIdent "
 					"will be re-tried", port);
-				pe[port].discover_port_identity_timer =
+				pe[port].discover_identity_timer =
 						get_time().val + PD_T_VDM_BUSY;
 			} else {
 				/*
 				 * Cable gave us an incorrect size or command,
 				 * mark discovery as failed
 				 */
-				pe[port].cable.discovery = PD_DISC_FAIL;
+				pd_set_identity_discovery(port, sop,
+						PD_DISC_FAIL);
 				CPRINTS("C%d: Unexpected cable response: "
 					"0x%04x 0x%04x", port,
 					rx_emsg[port].header, payload[0]);
@@ -4253,9 +4259,9 @@ static void pe_vdm_identity_request_cbl_run(int port)
 
 static void pe_vdm_identity_request_cbl_exit(int port)
 {
-	if (pe[port].discover_port_identity_counter >=
-						N_DISCOVER_IDENTITY_COUNT)
-		pe[port].cable.discovery = PD_DISC_FAIL;
+	if (pe[port].discover_identity_counter >= N_DISCOVER_IDENTITY_COUNT)
+		pd_set_identity_discovery(port, TCPC_TX_SOP_PRIME,
+				PD_DISC_FAIL);
 
 	/*
 	 * Set discover identity timer unless BUSY case already did so
@@ -4264,9 +4270,9 @@ static void pe_vdm_identity_request_cbl_exit(int port)
 	 * contract, so we could re-try faster from src_discovery if
 	 * desired here
 	 */
-	if (pe[port].cable.discovery == PD_DISC_NEEDED &&
-			pe[port].discover_port_identity_timer > get_time().val)
-		pe[port].discover_port_identity_timer = get_time().val +
+	if (pd_get_identity_discovery(port, TCPC_TX_SOP_PRIME) == PD_DISC_NEEDED
+			   && pe[port].discover_identity_timer > get_time().val)
+		pe[port].discover_identity_timer = get_time().val +
 							PD_T_DISCOVER_IDENTITY;
 }
 
@@ -4332,7 +4338,7 @@ static void pe_init_port_vdm_identity_request_run(int port)
 				/*
 				 * PE_INIT_PORT_VDM_Identity_NAKed embedded here
 				 */
-				pd_set_identity_discovery(port, TCPC_TX_SOP,
+				pd_set_identity_discovery(port, sop,
 							  PD_DISC_FAIL);
 			} else if (PD_VDO_CMDT(payload[0]) == CMDT_RSP_BUSY) {
 				/*
@@ -4344,14 +4350,14 @@ static void pe_init_port_vdm_identity_request_run(int port)
 				 */
 				CPRINTS("C%d: Partner Busy, DiscIdent "
 					"will be re-tried", port);
-				pe[port].discover_port_identity_timer =
+				pe[port].discover_identity_timer =
 						get_time().val + PD_T_VDM_BUSY;
 			} else {
 				/*
 				 * Partner gave an incorrect size or command,
 				 * mark discovery as failed
 				 */
-				pd_set_identity_discovery(port, TCPC_TX_SOP,
+				pd_set_identity_discovery(port, sop,
 							  PD_DISC_FAIL);
 				CPRINTS("C%d: Unexpected partner response: "
 					"0x%04x 0x%04x", port,
@@ -4362,8 +4368,7 @@ static void pe_init_port_vdm_identity_request_run(int port)
 			 * Partner doesn't support structured VDMs, mark
 			 * discovery as failed
 			 */
-			pd_set_identity_discovery(port, TCPC_TX_SOP,
-							  PD_DISC_FAIL);
+			pd_set_identity_discovery(port, sop, PD_DISC_FAIL);
 		} else {
 			/*
 			 * Return to PE_S[RC,NK]_Ready to process unexpected
@@ -5005,7 +5010,7 @@ static void pe_vcs_turn_off_vconn_swap_run(int port)
 		 * A VCONN Swap Shall reset the DiscoverIdentityCounter
 		 * to zero
 		 */
-		pe[port].discover_port_identity_counter = 0;
+		pe[port].discover_identity_counter = 0;
 		pe[port].dr_swap_attempt_counter = 0;
 
 		if (pe[port].power_role == PD_ROLE_SOURCE)
@@ -5061,7 +5066,7 @@ static void pe_vcs_send_ps_rdy_swap_run(int port)
 			 * A VCONN Swap Shall reset the
 			 * DiscoverIdentityCounter to zero
 			 */
-			pe[port].discover_port_identity_counter = 0;
+			pe[port].discover_identity_counter = 0;
 			pe[port].dr_swap_attempt_counter = 0;
 
 			if (pe[port].power_role == PD_ROLE_SOURCE)
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 6033a4cfa0..d5e133bfe0 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -544,9 +544,6 @@ struct pd_cable {
 	/* For storing Discover mode response from cable */
 	union tbt_mode_resp_cable cable_mode_resp;
 
-	/* Note: this field is for TCPMv2's probing process */
-	enum pd_discovery_state discovery;
-
 	/* Shared fields between TCPMv1 and TCPMv2 */
 	uint8_t is_identified;
 	/* Type of cable */
diff --git a/include/usb_pd_tcpm.h b/include/usb_pd_tcpm.h
index 1ad9e6b03d..6cc53209a1 100644
--- a/include/usb_pd_tcpm.h
+++ b/include/usb_pd_tcpm.h
@@ -92,7 +92,8 @@ enum tcpm_transmit_type {
 	TCPC_TX_SOP_DEBUG_PRIME_PRIME = 4,
 	TCPC_TX_HARD_RESET = 5,
 	TCPC_TX_CABLE_RESET = 6,
-	TCPC_TX_BIST_MODE_2 = 7
+	TCPC_TX_BIST_MODE_2 = 7,
+	TCPC_TX_INVALID = 0xf,
 };
 
 /* Number of valid Transmit Types */