TCPMv2: Remove PE_FLAGS_VDM_SETUP_DONE

Remove a PE flag that is redundant with the discovery state. Update the
discovery state where appropriate to keep it internally consistent.

BUG=b:189353401
TEST=voxel: Attach TBT4 hub; verify discovery sequence
BRANCH=none

Change-Id: I8ea870271ee95eb1dd4633370f7e39ca789f1328
Signed-off-by: Abe Levkoy <alevkoy@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4237156
Reviewed-by: Diana Z <dzigterman@chromium.org>

5 files changed, 55 insertions, 18 deletions

diff --git a/common/usb_pd_discovery.c b/common/usb_pd_discovery.c
index 9cadd197be..3fad82d10d 100644
--- a/common/usb_pd_discovery.c
+++ b/common/usb_pd_discovery.c
@@ -185,6 +185,17 @@ void dfp_consume_modes(int port, enum tcpci_msg_type type, int cnt,
 			       PD_DISC_COMPLETE);
 }
 
+void pd_disable_discovery(int port)
+{
+	/* Mark identity and SVIDs for the port partner and cable as failed.
+	 * With no discovered SVIDs, there are no modes to mark as failed.
+	 */
+	pd_set_identity_discovery(port, TCPCI_MSG_SOP, PD_DISC_FAIL);
+	pd_set_svids_discovery(port, TCPCI_MSG_SOP, PD_DISC_FAIL);
+	pd_set_identity_discovery(port, TCPCI_MSG_SOP_PRIME, PD_DISC_FAIL);
+	pd_set_svids_discovery(port, TCPCI_MSG_SOP_PRIME, PD_DISC_FAIL);
+}
+
 void pd_set_identity_discovery(int port, enum tcpci_msg_type type,
 			       enum pd_discovery_state disc)
 {
diff --git a/common/usbc/usb_pe_drp_sm.c b/common/usbc/usb_pe_drp_sm.c
index 249526d36e..5eb983a89c 100644
--- a/common/usbc/usb_pe_drp_sm.c
+++ b/common/usbc/usb_pe_drp_sm.c
@@ -1927,13 +1927,6 @@ __maybe_unused static bool pe_attempt_port_discovery(int port)
 	if (!IS_ENABLED(CONFIG_USB_PD_ALT_MODE_DFP))
 		assert(0);
 
-	/*
-	 * DONE set once modal entry is successful, discovery completes, or
-	 * discovery results in a NAK
-	 */
-	if (PE_CHK_FLAG(port, PE_FLAGS_VDM_SETUP_DONE))
-		return false;
-
 	/* Apply Port Discovery DR Swap Policy */
 	if (port_discovery_dr_swap_policy(
 		    port, pe[port].data_role,
@@ -1951,12 +1944,9 @@ __maybe_unused static bool pe_attempt_port_discovery(int port)
 	 */
 	if (pe[port].data_role == PD_ROLE_UFP &&
 	    prl_get_rev(port, TCPCI_MSG_SOP) == PD_REV20) {
-		pd_set_identity_discovery(port, TCPCI_MSG_SOP, PD_DISC_FAIL);
-		pd_set_identity_discovery(port, TCPCI_MSG_SOP_PRIME,
-					  PD_DISC_FAIL);
+		pd_disable_discovery(port);
 		pd_notify_event(port, PD_STATUS_EVENT_SOP_DISC_DONE);
 		pd_notify_event(port, PD_STATUS_EVENT_SOP_PRIME_DISC_DONE);
-		PE_SET_FLAG(port, PE_FLAGS_VDM_SETUP_DONE);
 		return false;
 	}
 
@@ -2009,7 +1999,6 @@ __maybe_unused static bool pe_attempt_port_discovery(int port)
 			set_state_pe(port, PE_INIT_VDM_MODES_REQUEST);
 			return true;
 		} else {
-			PE_SET_FLAG(port, PE_FLAGS_VDM_SETUP_DONE);
 			pd_timer_disable(port, PE_TIMER_DISCOVER_IDENTITY);
 			return false;
 		}
@@ -7782,7 +7771,6 @@ void pd_dfp_discovery_init(int port)
 		  BIT(task_get_current()));
 
 	memset(pe[port].discovery, 0, sizeof(pe[port].discovery));
-	PE_CLR_FLAG(port, PE_FLAGS_VDM_SETUP_DONE);
 }
 
 void pd_dfp_mode_init(int port)
diff --git a/common/usbc/usb_pe_private.h b/common/usbc/usb_pe_private.h
index c6703f6fd3..6bbf947bea 100644
--- a/common/usbc/usb_pe_private.h
+++ b/common/usbc/usb_pe_private.h
@@ -48,8 +48,6 @@ enum {
 	PE_FLAGS_PS_RESET_COMPLETE_FN,
 	/* VCONN swap operation has completed */
 	PE_FLAGS_VCONN_SWAP_COMPLETE_FN,
-	/* Flag to note no more setup VDMs (discovery, etc.) should be sent */
-	PE_FLAGS_VDM_SETUP_DONE_FN,
 	/* Flag to note PR Swap just completed for Startup entry */
 	PE_FLAGS_PR_SWAP_COMPLETE_FN,
 	/* Flag to note FRS/PRS context in shared state machine path */
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 08fa9b1dbd..ddc632e91c 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -1960,6 +1960,13 @@ void pd_dfp_discovery_init(int port);
 void pd_dfp_mode_init(int port);
 
 /**
+ * Mark all discovery types as failed to prevent any further discovery attempts
+ * until a connection change or DPM request triggers discovery again.
+ * @param port USB-C port number
+ */
+void pd_disable_discovery(int port);
+
+/**
  * Set identity discovery state for this type and port
  *
  * @param port  USB-C port number
diff --git a/test/usb_pe_drp_old.c b/test/usb_pe_drp_old.c
index 4ea07c1ec9..c352760d1d 100644
--- a/test/usb_pe_drp_old.c
+++ b/test/usb_pe_drp_old.c
@@ -83,11 +83,40 @@ void pd_set_error_recovery(int port)
 {
 }
 
+/* Skip discovery (and the corresponding DRS and VCS sequences) by default. A
+ * test may enable this to allow those sequences to run.
+ */
+static bool discovery_enabled;
+
+__override bool port_discovery_dr_swap_policy(int port, enum pd_data_role dr,
+					      bool dr_swap_flag)
+{
+	if (!discovery_enabled)
+		return false;
+
+	if (dr_swap_flag && dr == PD_ROLE_UFP)
+		return true;
+
+	return false;
+}
+
+__override bool port_discovery_vconn_swap_policy(int port, bool vconn_swap_flag)
+{
+	if (!discovery_enabled)
+		return false;
+
+	if (IS_ENABLED(CONFIG_USBC_VCONN) && vconn_swap_flag &&
+	    !tc_is_vconn_src(port) && tc_check_vconn_swap(port))
+		return true;
+
+	return false;
+}
+
 test_static void setup_source(void)
 {
 	/* Start PE. */
 	task_wait_event(10 * MSEC);
-	pe_set_flag(PORT0, PE_FLAGS_VDM_SETUP_DONE);
+	pd_disable_discovery(PORT0);
 	pe_set_flag(PORT0, PE_FLAGS_EXPLICIT_CONTRACT);
 	/* As long as we're hacking our way to ready, clear any DPM requests */
 	pe_clr_dpm_requests(PORT0);
@@ -103,7 +132,7 @@ test_static void setup_sink(void)
 	task_wait_event(10 * MSEC);
 	pd_comm_enable(PORT0, 1);
 	task_wait_event(10 * MSEC);
-	pe_set_flag(PORT0, PE_FLAGS_VDM_SETUP_DONE);
+	pd_disable_discovery(PORT0);
 	pe_set_flag(PORT0, PE_FLAGS_EXPLICIT_CONTRACT);
 	/* As long as we're hacking our way to ready, clear any DPM requests */
 	pe_clr_dpm_requests(PORT0);
@@ -131,7 +160,7 @@ static int test_pe_frs(void)
 	 * background tasks (ex. discovery) aren't running.
 	 */
 	tc_prs_src_snk_assert_rd(PORT0);
-	pe_set_flag(PORT0, PE_FLAGS_VDM_SETUP_DONE);
+	pd_disable_discovery(PORT0);
 	pe_set_flag(PORT0, PE_FLAGS_EXPLICIT_CONTRACT);
 	pe_clr_dpm_requests(PORT0);
 	set_state_pe(PORT0, PE_SNK_READY);
@@ -332,6 +361,8 @@ test_static int test_prl_is_busy(enum pd_power_role pr)
 {
 	int ready_state;
 
+	discovery_enabled = true;
+
 	if (pr == PD_ROLE_SOURCE)
 		ready_state = PE_SRC_READY;
 	else
@@ -363,6 +394,8 @@ test_static int test_prl_is_busy(enum pd_power_role pr)
 	 */
 	TEST_ASSERT(get_state_pe(PORT0) != ready_state);
 
+	discovery_enabled = false;
+
 	return EC_SUCCESS;
 }