pd: treat externally powered dualrole devices as dedicated chargers

Treat externally powered dualrole devices as dedicated chargers.
This allows us to default to consuming power from externally powered
dualrole devices and cancels a charger override when one is attached.

BUG=chrome-os-partner:38785
BRANCH=samus
TEST=tested with third-party dualrole device that can be externally
powered.

also tested with another samus that was hard-coded with externally
powered bit set, and deleted it's policy for power swapping. when
this externally-powered samus is plugged into a samus running this CL,
we always charge from the externally-powered samus.

Change-Id: I850eba668e86d311d9353aa3881fc3a518409630
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/263331
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

1 files changed, 34 insertions, 45 deletions

diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index 639de2c287..01da41cdaa 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -217,28 +217,6 @@ static uint32_t pd_src_caps[PD_PORT_COUNT][PDO_MAX_OBJECTS];
 static int pd_src_cap_cnt[PD_PORT_COUNT];
 #endif
 
-#define PD_FLAGS_PING_ENABLED      (1 << 0) /* SRC_READY pings enabled */
-#define PD_FLAGS_PARTNER_DR_POWER  (1 << 1) /* port partner is dualrole power */
-#define PD_FLAGS_PARTNER_DR_DATA   (1 << 2) /* port partner is dualrole data */
-#define PD_FLAGS_DATA_SWAPPED      (1 << 3) /* data swap complete */
-#define PD_FLAGS_SNK_CAP_RECVD     (1 << 4) /* sink capabilities received */
-#define PD_FLAGS_GET_SNK_CAP_SENT  (1 << 5) /* get sink cap sent */
-#define PD_FLAGS_EXPLICIT_CONTRACT (1 << 6) /* explicit pwr contract in place */
-#define PD_FLAGS_SFT_RST_DIS_COMM  (1 << 7) /* disable comms after soft reset */
-#define PD_FLAGS_PREVIOUS_PD_CONN  (1 << 8) /* previously PD connected */
-#define PD_FLAGS_CHECK_PR_ROLE     (1 << 9) /* check power role in READY */
-#define PD_FLAGS_CHECK_DR_ROLE     (1 << 10)/* check data role in READY */
-/* Flags to clear on a disconnect */
-#define PD_FLAGS_RESET_ON_DISCONNECT_MASK (PD_FLAGS_PARTNER_DR_POWER | \
-					   PD_FLAGS_PARTNER_DR_DATA | \
-					   PD_FLAGS_DATA_SWAPPED | \
-					   PD_FLAGS_SNK_CAP_RECVD | \
-					   PD_FLAGS_GET_SNK_CAP_SENT | \
-					   PD_FLAGS_EXPLICIT_CONTRACT | \
-					   PD_FLAGS_PREVIOUS_PD_CONN | \
-					   PD_FLAGS_CHECK_PR_ROLE | \
-					   PD_FLAGS_CHECK_DR_ROLE)
-
 static struct pd_protocol {
 	/* current port power role (SOURCE or SINK) */
 	uint8_t power_role;
@@ -967,24 +945,39 @@ static void pd_send_request_msg(int port, int always_send_request)
 static void pd_update_pdo_flags(int port, uint32_t pdo)
 {
 	/* can only parse PDO flags if type is fixed */
-	if ((pdo & PDO_TYPE_MASK) == PDO_TYPE_FIXED) {
-		if (pdo & PDO_FIXED_DUAL_ROLE) {
-			pd[port].flags |= PD_FLAGS_PARTNER_DR_POWER;
-#ifdef CONFIG_CHARGE_MANAGER
-			charge_manager_update_dualrole(port, CAP_DUALROLE);
-#endif
-		} else {
-			pd[port].flags &= ~PD_FLAGS_PARTNER_DR_POWER;
-#ifdef CONFIG_CHARGE_MANAGER
-			charge_manager_update_dualrole(port, CAP_DEDICATED);
+	if ((pdo & PDO_TYPE_MASK) != PDO_TYPE_FIXED)
+		return;
+
+#ifdef CONFIG_USB_PD_DUAL_ROLE
+	if (pdo & PDO_FIXED_DUAL_ROLE)
+		pd[port].flags |= PD_FLAGS_PARTNER_DR_POWER;
+	else
+		pd[port].flags &= ~PD_FLAGS_PARTNER_DR_POWER;
+
+	if (pdo & PDO_FIXED_EXTERNAL)
+		pd[port].flags |= PD_FLAGS_PARTNER_EXTPOWER;
+	else
+		pd[port].flags &= ~PD_FLAGS_PARTNER_EXTPOWER;
 #endif
-		}
 
-		if (pdo & PDO_FIXED_DATA_SWAP)
-			pd[port].flags |= PD_FLAGS_PARTNER_DR_DATA;
-		else
-			pd[port].flags &= ~PD_FLAGS_PARTNER_DR_DATA;
+	if (pdo & PDO_FIXED_DATA_SWAP)
+		pd[port].flags |= PD_FLAGS_PARTNER_DR_DATA;
+	else
+		pd[port].flags &= ~PD_FLAGS_PARTNER_DR_DATA;
+
+#ifdef CONFIG_CHARGE_MANAGER
+	/*
+	 * If partner supports power swap and is NOT externally powered, then
+	 * treat this as a dualrole device. Otherwise, treat this as a
+	 * dedicated charger.
+	 */
+	if ((pd[port].flags & PD_FLAGS_PARTNER_DR_POWER) &&
+	    !(pd[port].flags & PD_FLAGS_PARTNER_EXTPOWER)) {
+		charge_manager_update_dualrole(port, CAP_DUALROLE);
+	} else {
+		charge_manager_update_dualrole(port, CAP_DEDICATED);
 	}
+#endif
 }
 
 static void handle_data_request(int port, uint16_t head,
@@ -2129,8 +2122,7 @@ void pd_task(void)
 			/* Check power role policy, which may trigger a swap */
 			if (pd[port].flags & PD_FLAGS_CHECK_PR_ROLE) {
 				pd_check_pr_role(port, PD_ROLE_SOURCE,
-						 pd[port].flags &
-						     PD_FLAGS_PARTNER_DR_POWER);
+						 pd[port].flags);
 				pd[port].flags &= ~PD_FLAGS_CHECK_PR_ROLE;
 				break;
 			}
@@ -2138,8 +2130,7 @@ void pd_task(void)
 			/* Check data role policy, which may trigger a swap */
 			if (pd[port].flags & PD_FLAGS_CHECK_DR_ROLE) {
 				pd_check_dr_role(port, pd[port].data_role,
-						 pd[port].flags &
-						     PD_FLAGS_PARTNER_DR_DATA);
+						 pd[port].flags);
 				pd[port].flags &= ~PD_FLAGS_CHECK_DR_ROLE;
 				break;
 			}
@@ -2496,8 +2487,7 @@ void pd_task(void)
 			/* Check power role policy, which may trigger a swap */
 			if (pd[port].flags & PD_FLAGS_CHECK_PR_ROLE) {
 				pd_check_pr_role(port, PD_ROLE_SINK,
-						 pd[port].flags &
-						     PD_FLAGS_PARTNER_DR_POWER);
+						 pd[port].flags);
 				pd[port].flags &= ~PD_FLAGS_CHECK_PR_ROLE;
 				break;
 			}
@@ -2505,8 +2495,7 @@ void pd_task(void)
 			/* Check data role policy, which may trigger a swap */
 			if (pd[port].flags & PD_FLAGS_CHECK_DR_ROLE) {
 				pd_check_dr_role(port, pd[port].data_role,
-						 pd[port].flags &
-						     PD_FLAGS_PARTNER_DR_DATA);
+						 pd[port].flags);
 				pd[port].flags &= ~PD_FLAGS_CHECK_DR_ROLE;
 				break;
 			}