pd: Remove ACCESSORY states

According to the USB-C spec, when a debug accessory is identified, we may
optionally establish USB PD communication over CC. Some DTS partners
(eg. servo_v4) expect us to speak PD, so let's make it so. There is no
need for special ACCESSORY states, these do not exist in the PD spec.

BRANCH=servo
BUG=chromium:737755,b:65837068
TEST=On scarlet, attach servo_v4 and verify scarlet charges. Also verify
EC and cr50 consoles are available through servo_v4.

Change-Id: I59d1ca50b4766509eccf38562cdf926578138585
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/693294
Commit-Ready: Shawn N <shawnn@chromium.org>
Tested-by: Shawn N <shawnn@chromium.org>
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/739995

12 files changed, 56 insertions, 141 deletions

diff --git a/board/eve/board.h b/board/eve/board.h
index 7235ea163d..21d0a3845a 100644
--- a/board/eve/board.h
+++ b/board/eve/board.h
@@ -19,7 +19,6 @@
 #define CONFIG_BOARD_HAS_BEFORE_RSMRST
 #define CONFIG_BOARD_VERSION
 #define CONFIG_BUTTON_COUNT 2
-#define CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
 #define CONFIG_DPTF
 #define CONFIG_FLASH_SIZE 0x80000
 #define CONFIG_FPU
diff --git a/board/kevin/board.h b/board/kevin/board.h
index 33f634e8db..a0a2498945 100644
--- a/board/kevin/board.h
+++ b/board/kevin/board.h
@@ -108,7 +108,6 @@
 #define CONFIG_TABLET_MODE_SWITCH
 
 /* USB PD config */
-#define CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
 #define CONFIG_CHARGE_MANAGER
 #define CONFIG_USB_POWER_DELIVERY
 #define CONFIG_USB_PD_ALT_MODE
diff --git a/board/pyro/board.h b/board/pyro/board.h
index 0ddfb2b572..d47052e5bf 100644
--- a/board/pyro/board.h
+++ b/board/pyro/board.h
@@ -76,7 +76,6 @@
 #define GPIO_USB_CTL1 GPIO_EN_PP5000
 
 /* USB PD config */
-#define CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
 #define CONFIG_CMD_PD_CONTROL
 #define CONFIG_USB_PD_ALT_MODE
 #define CONFIG_USB_PD_ALT_MODE_DFP
diff --git a/board/reef/board.h b/board/reef/board.h
index d30a158d36..9941bd6b5c 100644
--- a/board/reef/board.h
+++ b/board/reef/board.h
@@ -80,7 +80,6 @@
 #define CONFIG_TABLET_MODE
 
 /* USB PD config */
-#define CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
 #define CONFIG_CMD_PD_CONTROL
 #define CONFIG_USB_PD_ALT_MODE
 #define CONFIG_USB_PD_ALT_MODE_DFP
diff --git a/board/servo_v4/board.c b/board/servo_v4/board.c
index c83c48072d..6eed57e862 100644
--- a/board/servo_v4/board.c
+++ b/board/servo_v4/board.c
@@ -6,7 +6,6 @@
 
 #include "adc.h"
 #include "adc_chip.h"
-#include "case_closed_debug.h"
 #include "common.h"
 #include "console.h"
 #include "ec_version.h"
@@ -415,9 +414,9 @@ static void check_for_disconnect(void)
 	ccd_keepalive_enabled = 0;
 }
 
-void ccd_set_mode(enum ccd_mode new_mode)
+void ccd_enable(int enable)
 {
-	if (new_mode == CCD_MODE_ENABLED) {
+	if (enable) {
 		/*
 		 * Unfortunately the polarity detect is designed for real plug
 		 * events, and only accurately detects pre-connect idle. If
@@ -434,7 +433,7 @@ void ccd_set_mode(enum ccd_mode new_mode)
 			/* Allow some time following turning on of VBUS */
 			hook_call_deferred(&ccd_measure_sbu_data,
 					   PD_POWER_SUPPLY_TURN_ON_DELAY);
-	} else if (new_mode == CCD_MODE_DISABLED) {
+	} else {
 		/* We are not connected to anything */
 
 		/* Disable ccd_measure_sbu deferred call always */
diff --git a/board/servo_v4/board.h b/board/servo_v4/board.h
index e79da62c7e..dfe8b77e15 100644
--- a/board/servo_v4/board.h
+++ b/board/servo_v4/board.h
@@ -86,7 +86,6 @@
 #undef CONFIG_TASK_PROFILING
 
 #define CONFIG_USB_POWER_DELIVERY
-#define CONFIG_USB_PD_DTS
 #define CONFIG_CMD_PD
 #define CONFIG_USB_PD_DUAL_ROLE
 #define CONFIG_USB_PD_DYNAMIC_SRC_CAP
@@ -210,5 +209,11 @@ int pd_set_rp_rd(int port, int cc_pull, int rp_value);
  */
 int board_get_version(void);
 
+/**
+ * Enable or disable CCD
+ *
+ * @param enable Enable CCD if true, otherwise disable
+ */
+void ccd_enable(int enable);
 #endif /* !__ASSEMBLER__ */
 #endif /* __CROS_EC_BOARD_H */
diff --git a/board/servo_v4/usb_pd_policy.c b/board/servo_v4/usb_pd_policy.c
index a4e057ef6c..9cf81a9dce 100644
--- a/board/servo_v4/usb_pd_policy.c
+++ b/board/servo_v4/usb_pd_policy.c
@@ -415,6 +415,10 @@ int pd_set_power_supply_ready(int port)
 	vbus[DUT].mv = 5000;
 	vbus[DUT].ma = 500;
 
+	/* Enable CCD, if debuggable TS attached */
+	if (pd_ts_dts_plugged(DUT))
+		ccd_enable(1);
+
 	return EC_SUCCESS; /* we are ready */
 }
 
@@ -424,6 +428,8 @@ void pd_power_supply_reset(int port)
 	if (port == CHG)
 		return;
 
+	ccd_enable(0);
+
 	/* Disable VBUS */
 	gpio_set_level(GPIO_DUT_CHG_EN, 0);
 	/* Set default VBUS source to Host */
diff --git a/board/snappy/board.h b/board/snappy/board.h
index c6673ae719..1e62bb0829 100644
--- a/board/snappy/board.h
+++ b/board/snappy/board.h
@@ -75,7 +75,6 @@
 #define GPIO_USB_CTL1 GPIO_EN_PP5000
 
 /* USB PD config */
-#define CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
 #define CONFIG_CMD_PD_CONTROL
 #define CONFIG_USB_PD_ALT_MODE
 #define CONFIG_USB_PD_ALT_MODE_DFP
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index d85e8ea83c..26615fd037 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -5,7 +5,6 @@
 
 #include "battery.h"
 #include "board.h"
-#include "case_closed_debug.h"
 #include "charge_manager.h"
 #include "charge_state.h"
 #include "chipset.h"
@@ -113,8 +112,6 @@ static struct pd_protocol {
 	uint8_t power_role;
 	/* current port data role (DFP or UFP) */
 	uint8_t data_role;
-	/* port flags, see PD_FLAGS_* */
-	uint16_t flags;
 	/* 3-bit rolling message ID counter */
 	uint8_t msg_id;
 	/* Port polarity : 0 => CC1 is CC line, 1 => CC2 is CC line */
@@ -125,6 +122,8 @@ static struct pd_protocol {
 	enum pd_states last_state;
 	/* The state to go to after timeout */
 	enum pd_states timeout_state;
+	/* port flags, see PD_FLAGS_* */
+	uint32_t flags;
 	/* Timeout for the current state. Set to 0 for no timeout. */
 	uint64_t timeout;
 	/* Time for source recovery after hard reset */
@@ -171,12 +170,12 @@ static const char * const pd_state_names[] = {
 	"DISABLED", "SUSPENDED",
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 	"SNK_DISCONNECTED", "SNK_DISCONNECTED_DEBOUNCE",
-	"SNK_ACCESSORY", "SNK_HARD_RESET_RECOVER",
+	"SNK_HARD_RESET_RECOVER",
 	"SNK_DISCOVERY", "SNK_REQUESTED", "SNK_TRANSITION", "SNK_READY",
 	"SNK_SWAP_INIT", "SNK_SWAP_SNK_DISABLE",
 	"SNK_SWAP_SRC_DISABLE", "SNK_SWAP_STANDBY", "SNK_SWAP_COMPLETE",
 #endif /* CONFIG_USB_PD_DUAL_ROLE */
-	"SRC_DISCONNECTED", "SRC_DISCONNECTED_DEBOUNCE", "SRC_ACCESSORY",
+	"SRC_DISCONNECTED", "SRC_DISCONNECTED_DEBOUNCE",
 	"SRC_HARD_RESET_RECOVER", "SRC_STARTUP",
 	"SRC_DISCOVERY", "SRC_NEGOCIATE", "SRC_ACCEPTED", "SRC_POWERED",
 	"SRC_TRANSITION", "SRC_READY", "SRC_GET_SNK_CAP", "DR_SWAP",
@@ -232,6 +231,15 @@ int pd_is_connected(int port)
 		pd[port].task_state != PD_STATE_SRC_DISCONNECTED_DEBOUNCE);
 }
 
+/*
+ * Return true if partner port is a DTS or TS capable of entering debug
+ * mode (eg. is presenting Rp/Rp or Rd/Rd).
+ */
+int pd_ts_dts_plugged(int port)
+{
+	return pd[port].flags & PD_FLAGS_TS_DTS_PARTNER;
+}
+
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 void pd_vbus_low(int port)
 {
@@ -246,17 +254,6 @@ static inline int pd_is_vbus_present(int port)
 	return pd_snk_is_vbus_provided(port);
 #endif
 }
-
-static int pd_debug_acc_plugged(int port)
-{
-#ifdef CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
-	return pd[port].task_state == PD_STATE_SRC_ACCESSORY ||
-		pd[port].task_state == PD_STATE_SNK_ACCESSORY;
-#else
-	/* Debug accessories not supported */
-	return 0;
-#endif
-}
 #endif
 
 static inline void set_state(int port, enum pd_states next_state)
@@ -1272,7 +1269,7 @@ void pd_update_dual_role_config(int port)
 	 * disconnected state).
 	 */
 	if (pd[port].power_role == PD_ROLE_SOURCE &&
-	    ((drp_state == PD_DRP_FORCE_SINK && !pd_debug_acc_plugged(port)) ||
+	    ((drp_state == PD_DRP_FORCE_SINK && !pd_ts_dts_plugged(port)) ||
 	     (drp_state == PD_DRP_TOGGLE_OFF
 	      && pd[port].task_state == PD_STATE_SRC_DISCONNECTED))) {
 		pd[port].power_role = PD_ROLE_SINK;
@@ -1722,13 +1719,18 @@ void pd_task(void)
 
 			/* Debounce complete */
 			/* UFP is attached */
-			if (new_cc_state == PD_CC_UFP_ATTACHED) {
-				pd[port].polarity = (cc2 == TYPEC_CC_VOLT_RD);
+			if (new_cc_state == PD_CC_UFP_ATTACHED ||
+			    new_cc_state == PD_CC_DEBUG_ACC) {
+				pd[port].polarity = (cc1 != TYPEC_CC_VOLT_RD);
 				tcpm_set_polarity(port, pd[port].polarity);
 
 				/* initial data role for source is DFP */
 				pd_set_data_role(port, PD_ROLE_DFP);
 
+				if (new_cc_state == PD_CC_DEBUG_ACC)
+					pd[port].flags |=
+						PD_FLAGS_TS_DTS_PARTNER;
+
 #ifndef CONFIG_USBC_BACKWARDS_COMPATIBLE_DFP
 				/* Enable VBUS */
 				if (pd_set_power_supply_ready(port)) {
@@ -1755,60 +1757,10 @@ void pd_task(void)
 				timeout = 5*MSEC;
 				set_state(port, PD_STATE_SRC_STARTUP);
 			}
-			/* Accessory is attached */
-			else if (new_cc_state == PD_CC_AUDIO_ACC ||
-				 new_cc_state == PD_CC_DEBUG_ACC) {
-#ifdef CONFIG_USBC_BACKWARDS_COMPATIBLE_DFP
-				/* Remove VBUS */
-				pd_power_supply_reset(port);
-#endif
-				/* Set the USB muxes and the default USB role */
-				pd_set_data_role(port, CONFIG_USB_PD_DEBUG_DR);
-
-#ifdef CONFIG_USB_PD_DTS
-				if (new_cc_state == PD_CC_DEBUG_ACC) {
-					ccd_set_mode(system_is_locked() ?
-						     CCD_MODE_PARTIAL :
-						     CCD_MODE_ENABLED);
-
-					/* Enable Vbus */
-					pd_set_power_supply_ready(port);
-					/* Captive cable, CC1 always */
-					pd[port].polarity = 0;
-					tcpm_set_polarity(port, 0);
-					/* Enable TCPC RX */
-					if (pd_comm_enabled)
-						tcpm_set_rx_enable(port, 1);
-					pd[port].flags |=
-						PD_FLAGS_CHECK_DR_ROLE;
-					hard_reset_count = 0;
-					timeout = 10*MSEC;
-					set_state(port, PD_STATE_SRC_STARTUP);
-					break;
-				}
-#endif
-				set_state(port, PD_STATE_SRC_ACCESSORY);
-			}
-			break;
-		case PD_STATE_SRC_ACCESSORY:
-			/* Combined audio / debug accessory state */
-			timeout = 100*MSEC;
-
-			tcpm_get_cc(port, &cc1, &cc2);
-
-			/* If accessory becomes detached */
-			if ((pd[port].cc_state == PD_CC_AUDIO_ACC &&
-			     (cc1 != TYPEC_CC_VOLT_RA ||
-			      cc2 != TYPEC_CC_VOLT_RA)) ||
-			    (pd[port].cc_state == PD_CC_DEBUG_ACC &&
-			     (cc1 != TYPEC_CC_VOLT_RD ||
-			      cc2 != TYPEC_CC_VOLT_RD))) {
-				set_state(port, PD_STATE_SRC_DISCONNECTED);
-#ifdef CONFIG_USB_PD_DTS
-				ccd_set_mode(CCD_MODE_DISABLED);
-#endif
-				timeout = 10*MSEC;
-			}
+			/*
+			 * AUDIO_ACC will remain in this state indefinitely
+			 * until disconnect.
+			 */
 			break;
 		case PD_STATE_SRC_HARD_RESET_RECOVER:
 			/* Do not continue until hard reset recovery time */
@@ -2241,32 +2193,20 @@ void pd_task(void)
 				tcpm_set_rx_enable(port, 1);
 
 			/* DFP is attached */
-			if (new_cc_state == PD_CC_DFP_ATTACHED) {
+			if (new_cc_state == PD_CC_DFP_ATTACHED ||
+			    new_cc_state == PD_CC_DEBUG_ACC) {
 				pd[port].flags |= PD_FLAGS_CHECK_PR_ROLE |
 						  PD_FLAGS_CHECK_DR_ROLE |
 						  PD_FLAGS_CHECK_IDENTITY;
+				if (new_cc_state == PD_CC_DEBUG_ACC)
+					pd[port].flags |=
+						PD_FLAGS_TS_DTS_PARTNER;
 				set_state(port, PD_STATE_SNK_DISCOVERY);
 				timeout = 10*MSEC;
 				hook_call_deferred(
 					&pd_usb_billboard_deferred_data,
 					PD_T_AME);
 			}
-#ifdef CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
-			else if (new_cc_state == PD_CC_DEBUG_ACC)
-				set_state(port, PD_STATE_SNK_ACCESSORY);
-			break;
-		case PD_STATE_SNK_ACCESSORY:
-			/* debug accessory state */
-			timeout = 100*MSEC;
-
-			tcpm_get_cc(port, &cc1, &cc2);
-
-			/* If accessory becomes detached */
-			if (!cc_is_rp(cc1) || !cc_is_rp(cc2)) {
-				set_state(port, PD_STATE_SNK_DISCONNECTED);
-				timeout = 10*MSEC;
-			}
-#endif
 			break;
 		case PD_STATE_SNK_HARD_RESET_RECOVER:
 			if (pd[port].last_state != pd[port].task_state)
@@ -2803,9 +2743,6 @@ void pd_task(void)
 				set_state(port, PD_STATE_SRC_DISCONNECTED);
 				/* Debouncing */
 				timeout = 10*MSEC;
-#ifdef CONFIG_USB_PD_DTS
-				ccd_set_mode(CCD_MODE_DISABLED);
-#endif
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 				/*
 				 * If Try.SRC is configured, then ATTACHED_SRC
diff --git a/include/case_closed_debug.h b/include/case_closed_debug.h
index b41532bc5e..6a8ce14ffc 100644
--- a/include/case_closed_debug.h
+++ b/include/case_closed_debug.h
@@ -7,34 +7,6 @@
 #ifndef __CROS_EC_CASE_CLOSED_DEBUG_H
 #define __CROS_EC_CASE_CLOSED_DEBUG_H
 
-enum ccd_mode {
-	/*
-	 * The disabled mode tri-states the DP and DN lines.
-	 */
-	CCD_MODE_DISABLED,
-
-	/*
-	 * The partial mode allows some CCD functionality and is to be set
-	 * when the device is write protected and a CCD cable is detected.
-	 * This mode gives access to the APs console.
-	 */
-	CCD_MODE_PARTIAL,
-
-	/*
-	 * The fully enabled mode is used in factory and test lab
-	 * configurations where it is acceptable to be able to reflash the
-	 * device over CCD.
-	 */
-	CCD_MODE_ENABLED,
-
-	CCD_MODE_COUNT,
-};
-
-/*
- * Set current CCD mode, this function is idempotent.
- */
-void ccd_set_mode(enum ccd_mode new_mode);
-
 /**
  * Return non-zero if the CCD external interface is enabled.
  */
diff --git a/include/config.h b/include/config.h
index d461e2e770..660f067850 100644
--- a/include/config.h
+++ b/include/config.h
@@ -336,9 +336,6 @@
  */
 #undef CONFIG_BUTTON_COUNT
 
-/* The case close debug (CCD) feature is provided by an external chip. */
-#undef CONFIG_CASE_CLOSED_DEBUG_EXTERNAL
-
 /*
  * Capsense chip has buttons, too.
  */
@@ -2048,9 +2045,6 @@
  */
 #undef CONFIG_USB_PD_DISCHARGE_TCPC
 
-/* Define if this board is acting as a Debug Test System (DTS) */
-#undef CONFIG_USB_PD_DTS
-
 /* Define if this board can act as a dual-role PD port (source and sink) */
 #undef CONFIG_USB_PD_DUAL_ROLE
 
diff --git a/include/usb_pd.h b/include/usb_pd.h
index bfdc55f6e6..32cba85158 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -635,7 +635,6 @@ enum pd_states {
 #ifdef CONFIG_USB_PD_DUAL_ROLE
 	PD_STATE_SNK_DISCONNECTED,
 	PD_STATE_SNK_DISCONNECTED_DEBOUNCE,
-	PD_STATE_SNK_ACCESSORY,
 	PD_STATE_SNK_HARD_RESET_RECOVER,
 	PD_STATE_SNK_DISCOVERY,
 	PD_STATE_SNK_REQUESTED,
@@ -651,7 +650,6 @@ enum pd_states {
 
 	PD_STATE_SRC_DISCONNECTED,
 	PD_STATE_SRC_DISCONNECTED_DEBOUNCE,
-	PD_STATE_SRC_ACCESSORY,
 	PD_STATE_SRC_HARD_RESET_RECOVER,
 	PD_STATE_SRC_STARTUP,
 	PD_STATE_SRC_DISCOVERY,
@@ -707,6 +705,7 @@ enum pd_states {
 #define PD_FLAGS_TRY_SRC           (1 << 13)/* Try.SRC states are active */
 #define PD_FLAGS_PARTNER_USB_COMM  (1 << 14)/* port partner is USB comms */
 #define PD_FLAGS_UPDATE_SRC_CAPS   (1 << 15)/* send new source capabilities */
+#define PD_FLAGS_TS_DTS_PARTNER    (1 << 16)/* partner has rp/rp or rd/rd */
 /* Flags to clear on a disconnect */
 #define PD_FLAGS_RESET_ON_DISCONNECT_MASK (PD_FLAGS_PARTNER_DR_POWER | \
 					   PD_FLAGS_PARTNER_DR_DATA | \
@@ -721,8 +720,8 @@ enum pd_states {
 					   PD_FLAGS_VCONN_ON | \
 					   PD_FLAGS_TRY_SRC | \
 					   PD_FLAGS_PARTNER_USB_COMM | \
-					   PD_FLAGS_UPDATE_SRC_CAPS)
-
+					   PD_FLAGS_UPDATE_SRC_CAPS | \
+					   PD_FLAGS_TS_DTS_PARTNER)
 
 enum pd_cc_states {
 	PD_CC_NONE,
@@ -1568,6 +1567,14 @@ void pd_prepare_reset(void);
  */
 void pd_set_new_power_request(int port);
 
+/**
+ * Return true if partner port is a DTS or TS capable of entering debug
+ * mode (eg. is presenting Rp/Rp or Rd/Rd).
+ *
+ * @param port USB-C port number
+ */
+int pd_ts_dts_plugged(int port);
+
 /* ----- Logging ----- */
 #ifdef CONFIG_USB_PD_LOGGING
 /**