[PATCH v2 3/4] platform/chrome: cros_ec_typec: Configure muxes at start of port update

From: Prashant Malani
Date: Tue Feb 08 2022 - 13:48:07 EST


There are situations where the mux state reported by the Embedded
Controller (EC), might lag the partner "connected" state. So, the mux
state might still suggest that a partner is connected, while the PD
"connected" state, being in Try.SNK (for example) suggests that the
partner is disconnected.

In such a scenario, we will end up sending a disconnect command to the
mux driver, followed by a connect command, since the mux is configured
later. Avoid this by configuring the mux before
registering/disconnecting a partner.

Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
---

Changes in v2:
- Change return at end of port_update() to just return 0.

drivers/platform/chrome/cros_ec_typec.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 3d34ece7f790..3019e29f200d 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -965,6 +965,11 @@ static int cros_typec_port_update(struct cros_typec_data *typec, int port_num)
if (ret < 0)
return ret;

+ /* Update the switches if they exist, according to requested state */
+ ret = cros_typec_configure_mux(typec, port_num, &resp);
+ if (ret)
+ dev_warn(typec->dev, "Configure muxes failed, err = %d\n", ret);
+
dev_dbg(typec->dev, "Enabled %d: 0x%hhx\n", port_num, resp.enabled);
dev_dbg(typec->dev, "Role %d: 0x%hhx\n", port_num, resp.role);
dev_dbg(typec->dev, "Polarity %d: 0x%hhx\n", port_num, resp.polarity);
@@ -980,12 +985,7 @@ static int cros_typec_port_update(struct cros_typec_data *typec, int port_num)
if (typec->typec_cmd_supported)
cros_typec_handle_status(typec, port_num);

- /* Update the switches if they exist, according to requested state */
- ret = cros_typec_configure_mux(typec, port_num, &resp);
- if (ret)
- dev_warn(typec->dev, "Configure muxes failed, err = %d\n", ret);
-
- return ret;
+ return 0;
}

static int cros_typec_get_cmd_version(struct cros_typec_data *typec)
--
2.35.0.263.gb82422642f-goog