[PATCH v1] usb: typec: tcpm: Disregard vbus off while in PR_SWAP_SNK_SRC_SOURCE_ON

From: Badhri Jagan Sridharan
Date: Tue Nov 24 2020 - 21:07:53 EST


During PR_SWAP sequence, when TCPM is waiting in PR_SWAP_SNK_SRC_SOURCE_ON
for the vbus source to ramp up, TCPM would prematurely exit
PR_SWAP_SNK_SRC_SOURCE_ON and transition to SNK_UNATTACHED state when a
vbus off notification is received. This should not be the case as vbus
can still be off while in PR_SWAP_SNK_SRC_SOURCE_ON and the vbus source
has PD_T_NEWSRC to ramp up.

Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
---
drivers/usb/typec/tcpm/tcpm.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 4aac0efdb720..277b9d4d9c84 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4218,6 +4218,14 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port)
/* Do nothing, expected */
break;

+ case PR_SWAP_SNK_SRC_SOURCE_ON:
+ /*
+ * Do nothing when vbus off notification is received.
+ * TCPM can wait for PD_T_NEWSRC in PR_SWAP_SNK_SRC_SOURCE_ON
+ * for the vbus source to ramp up.
+ */
+ break;
+
case PORT_RESET_WAIT_OFF:
tcpm_set_state(port, tcpm_default_state(port), 0);
break;
--
2.29.2.454.gaff20da3a2-goog