charge_manager: Consider port in source PDO.

When CONFIG_USB_PD_MAX_SINGLE_SOURCE_CURRENT is defined for a board, as
its name implies, the board can source a higher current if there is
only one port acting as a source.

This commit fixes an issue with selecting the right source capability
message to advertise.  charge_manager_get_source_pdo() was simply
checking if there was more than one sink connected, instead of checking
if there were any *other* sinks connected.  In the event that a sink
was connected to a different port, we would advertise the max source
PDO.

BUG=b:64037926, b:35577509
BRANCH=gru,eve,reef
TEST=Connect sink to port 1.  Connect a AMA to port 0 that claims that
VBUS isn't necessary.  Start sending source caps, verify that the max
PDO is not being advertised in the source caps.

Change-Id: Ie4145ecaf98d5b9070ad3e8b139e5653685fa801
Signed-off-by: Aseda Aboagye <aaboagye@google.com>
Reviewed-on: https://chromium-review.googlesource.com/610479
Commit-Ready: Aseda Aboagye <aaboagye@chromium.org>
Tested-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Shawn N <shawnn@chromium.org>

1 files changed, 12 insertions, 12 deletions

diff --git a/common/charge_manager.c b/common/charge_manager.c
index 7b119da347..9d9226cb19 100644
--- a/common/charge_manager.c
+++ b/common/charge_manager.c
@@ -963,20 +963,20 @@ void charge_manager_source_port(int port, int enable)
 	}
 }
 
-int charge_manager_get_source_pdo(const uint32_t **src_pdo)
+int charge_manager_get_source_pdo(const uint32_t **src_pdo, const int port)
 {
-	int p;
-	int count = 0;
-
-	/* count the number of connected sinks */
-	for (p = 0; p < CONFIG_USB_PD_PORT_COUNT; p++)
-		if (source_port_bitmap & (1 << p))
-			count++;
-
-	/* send the maximum current if we are sourcing only on one port */
-	*src_pdo = count <= 1 ? pd_src_pdo_max : pd_src_pdo;
+	/* Are there any other connected sinks? */
+	if (source_port_bitmap & ~(1 << port)) {
+		*src_pdo = pd_src_pdo;
+		return pd_src_pdo_cnt;
+	}
 
-	return count <= 1 ? pd_src_pdo_cnt : pd_src_pdo_max_cnt;
+	/*
+	 * If not, send the maximum current since we're sourcing on only one
+	 * port.
+	 */
+	*src_pdo = pd_src_pdo_max;
+	return pd_src_pdo_max_cnt;
 }
 #endif /* CONFIG_USB_PD_MAX_SINGLE_SOURCE_CURRENT */