[PATCH v1] usb: typec: tcpm: Fix response to vsafe0V event

[Badhri Jagan Sridharan <badhri@google.com>]

Do not transition to SNK_UNATTACHED state when receiving vsafe0v event
while in SNK_HARD_RESET_WAIT_VBUS. Ignore VBUS off events as well as
in some platforms VBUS off can be signalled more than once.

[143515.364753] Requesting mux state 1, usb-role 2, orientation 2
[143515.365520] pending state change SNK_HARD_RESET_SINK_OFF -> SNK_HARD_RESET_SINK_ON @ 650 ms [rev3 HARD_RESET]
[143515.632281] CC1: 0 -> 0, CC2: 3 -> 0 [state SNK_HARD_RESET_SINK_OFF, polarity 1, disconnected]
[143515.637214] VBUS on
[143515.664985] VBUS off
[143515.664992] state change SNK_HARD_RESET_SINK_OFF -> SNK_HARD_RESET_WAIT_VBUS [rev3 HARD_RESET]
[143515.665564] VBUS VSAFE0V
[143515.665566] state change SNK_HARD_RESET_WAIT_VBUS -> SNK_UNATTACHED [rev3 HARD_RESET]

Fixes: 28b43d3d746b ("usb: typec: tcpm: Introduce vsafe0v for vbus")
Cc: <stable@vger.kernel.org>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 829d75ebab42..cc1d83926497 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5349,6 +5349,10 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port)
 		/* Do nothing, vbus drop expected */
 		break;
 
+	case SNK_HARD_RESET_WAIT_VBUS:
+		/* Do nothing, its OK to receive vbus off events */
+		break;
+
 	default:
 		if (port->pwr_role == TYPEC_SINK && port->attached)
 			tcpm_set_state(port, SNK_UNATTACHED, tcpm_wait_for_discharge(port));
@@ -5395,6 +5399,9 @@ static void _tcpm_pd_vbus_vsafe0v(struct tcpm_port *port)
 	case SNK_DEBOUNCED:
 		/*Do nothing, still waiting for VSAFE5V for connect */
 		break;
+	case SNK_HARD_RESET_WAIT_VBUS:
+		/* Do nothing, its OK to receive vbus off events */
+		break;
 	default:
 		if (port->pwr_role == TYPEC_SINK && port->auto_vbus_discharge_enabled)
 			tcpm_set_state(port, SNK_UNATTACHED, 0);

base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5
-- 
2.41.0.255.g8b1d071c50-goog