usb_pd TCPMv1: Maintain independent MessageID for SOP Prime

This patchset enables storage of MessageId counter received from the
cable plug.

Since SOP*(Cable) communication and SOP(Port Partner) have separate
MessageID counters, it is necessary to store separate messageIDs to
avoid the the incoming packets from getting dropped.

BUG=b:148481858
BRANCH=None
TEST=Tested on Volteer, able to maintain separate MessageId count for
     SOP and SOP' communication.

Change-Id: Iac2dc616f99a9e19914588e59441df8b09068afa
Signed-off-by: Ayushee <ayushee.shah@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2026650
Reviewed-by: Keith Short <keithshort@chromium.org>

3 files changed, 68 insertions, 9 deletions

diff --git a/common/usb_pd_policy.c b/common/usb_pd_policy.c
index 1b582b75d4..7ff9c3342d 100644
--- a/common/usb_pd_policy.c
+++ b/common/usb_pd_policy.c
@@ -167,12 +167,30 @@ int pd_charge_from_device(uint16_t vid, uint16_t pid)
 
 static struct pd_cable cable[CONFIG_USB_PD_PORT_MAX_COUNT];
 
-static bool is_transmit_msg_sop_prime(int port)
+bool is_transmit_msg_sop_prime(int port)
 {
 	return (IS_ENABLED(CONFIG_USB_PD_DECODE_SOP) &&
 		(cable[port].flags & CABLE_FLAGS_SOP_PRIME_ENABLE));
 }
 
+int cable_consume_repeat_message(int port, uint8_t msg_id)
+{
+
+	if (cable[port].last_cable_msg_id != msg_id) {
+		cable[port].last_cable_msg_id = msg_id;
+		return 0;
+	}
+	CPRINTF("C%d Cable repeat msg_id %d\n", port, msg_id);
+	return 1;
+
+}
+
+static void disable_transmit_sop_prime(int port)
+{
+	if (IS_ENABLED(CONFIG_USB_PD_DECODE_SOP))
+		cable[port].flags &= ~CABLE_FLAGS_SOP_PRIME_ENABLE;
+}
+
 uint8_t is_sop_prime_ready(int port,
 			   enum pd_data_role data_role,
 			   uint32_t pd_flags)
@@ -189,16 +207,33 @@ uint8_t is_sop_prime_ready(int port,
 	 * ensure that it is the Vconn Source
 	 */
 	if (pd_flags & PD_FLAGS_VCONN_ON && (IS_ENABLED(CONFIG_USB_PD_REV30) ||
-		data_role == PD_ROLE_DFP))
+		data_role == PD_ROLE_DFP)) {
 		return is_transmit_msg_sop_prime(port);
+	}
+	if (is_transmit_msg_sop_prime(port)) {
+		/*
+		 * Clear the CABLE_FLAGS_SOP_PRIME_ENABLE flag if the port is
+		 * unable to communicate with the cable plug.
+		 */
+		disable_transmit_sop_prime(port);
+	}
 
 	return 0;
 }
 
 void reset_pd_cable(int port)
 {
-	if (IS_ENABLED(CONFIG_USB_PD_DECODE_SOP))
+	if (IS_ENABLED(CONFIG_USB_PD_DECODE_SOP)) {
 		memset(&cable[port], 0, sizeof(cable[port]));
+		/*
+		 * Invalidate the last cable messageId counter. The cable
+		 * Message id starts from 0 to 7 and if last_cable msg_id
+		 * is initialized to 0, it will lead to repetitive message
+		 * id with first received packet. Hence, initialize it with
+		 * an invalid value 0xff.
+		 */
+		cable[port].last_cable_msg_id = 0xff;
+	}
 }
 
 enum idh_ptype get_usb_pd_cable_type(int port)
@@ -333,12 +368,6 @@ static void enable_transmit_sop_prime(int port)
 		cable[port].flags |= CABLE_FLAGS_SOP_PRIME_ENABLE;
 }
 
-static void disable_transmit_sop_prime(int port)
-{
-	if (IS_ENABLED(CONFIG_USB_PD_DECODE_SOP))
-		cable[port].flags &= ~CABLE_FLAGS_SOP_PRIME_ENABLE;
-}
-
 static bool is_tbt_compat_enabled(int port)
 {
 	return (IS_ENABLED(CONFIG_USB_PD_TBT_COMPAT_MODE) &&
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index 6e29bf06b8..18a6afdfbb 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -700,6 +700,14 @@ static int consume_repeat_message(int port, uint16_t msg_header)
 	if (PD_HEADER_TYPE(msg_header) == PD_CTRL_SOFT_RESET &&
 	    PD_HEADER_CNT(msg_header) == 0) {
 		return 0;
+	/* TODO: Check for incoming SOP'' messages */
+	} else if (is_transmit_msg_sop_prime(port)) {
+		/*
+		 * From USB PD version 1.3 section 6.7.1, the port which
+		 * communicates using SOP* Packets Shall maintain copy
+		 * of the last MessageID for each type of SOP* it uses.
+		 */
+		return cable_consume_repeat_message(port, msg_id);
 	} else if (pd[port].last_msg_id != msg_id) {
 		pd[port].last_msg_id = msg_id;
 	} else if (pd[port].last_msg_id == msg_id) {
diff --git a/include/usb_pd.h b/include/usb_pd.h
index eaff1212c9..8ce6335b7d 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -529,6 +529,8 @@ enum pd_rev_type {
 
 /* Cable structure for storing cable attributes */
 struct pd_cable {
+	/* Last received cable message id counter*/
+	uint8_t last_cable_msg_id;
 	uint8_t is_identified;
 	/* Type of cable */
 	enum idh_ptype type;
@@ -1683,6 +1685,26 @@ uint32_t *pd_get_mode_vdo(int port, uint16_t svid_idx);
 struct svdm_amode_data *pd_get_amode_data(int port, uint16_t svid);
 
 /**
+ * Returns 0 if previous cable messageId count is different from received
+ * messageId count.
+ *
+ * @param port		USB-C port number
+ * @param msg_id        Received cable msg_id
+ * @return              0 if Received MessageId count is different from the
+ *                      previous one.
+ *                      1 Otherwise
+ */
+int cable_consume_repeat_message(int port, uint8_t msg_id);
+
+/**
+ * Returns status of CABLE_FLAGS_SOP_PRIME_ENABLE flag
+ *
+ * @param port		USB-C port number
+ * @return              Status of CABLE_FLAGS_SOP_PRIME_ENABLE flag
+ */
+bool is_transmit_msg_sop_prime(int port);
+
+/**
  * Returns the status of cable flag - CABLE_FLAGS_SOP_PRIME_ENABLE
  *
  * @param port		USB-C port number