Revert "usb: typec: tcpm: clear pd_event queue in PORT_RESET"

This reverts commit bf20c69cf3cf9c6445c4925dd9a8a6ca1b78bfdf.

During tcpm_init() stage, if the VBUS is still present after
tcpm_reset_port(), then we assume that VBUS will off and goto safe0v
after a specific discharge time. Following a TCPM_VBUS_EVENT event if
VBUS reach to off state. TCPM_VBUS_EVENT event may be set during
PORT_RESET handling stage. If pd_events reset to 0 after TCPM_VBUS_EVENT
set, we will lost this VBUS event. Then the port state machine may stuck
at one state.

Before:

[    2.570172] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev1 NONE_AMS]
[    2.570179] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms]
[    2.570182] pending state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED @ 920 ms [rev1 NONE_AMS]
[    3.490213] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [delayed 920 ms]
[    3.490220] Start toggling
[    3.546050] CC1: 0 -> 0, CC2: 0 -> 2 [state TOGGLING, polarity 0, connected]
[    3.546057] state change TOGGLING -> SRC_ATTACH_WAIT [rev1 NONE_AMS]

After revert this patch, we can see VBUS off event and the port will goto
expected state.

[    2.441992] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev1 NONE_AMS]
[    2.441999] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms]
[    2.442002] pending state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED @ 920 ms [rev1 NONE_AMS]
[    2.442122] VBUS off
[    2.442125] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev1 NONE_AMS]
[    2.442127] VBUS VSAFE0V
[    2.442351] CC1: 0 -> 0, CC2: 0 -> 0 [state SNK_UNATTACHED, polarity 0, disconnected]
[    2.442357] Start toggling
[    2.491850] CC1: 0 -> 0, CC2: 0 -> 2 [state TOGGLING, polarity 0, connected]
[    2.491858] state change TOGGLING -> SRC_ATTACH_WAIT [rev1 NONE_AMS]
[    2.491863] pending state change SRC_ATTACH_WAIT -> SNK_TRY @ 200 ms [rev1 NONE_AMS]
[    2.691905] state change SRC_ATTACH_WAIT -> SNK_TRY [delayed 200 ms]

Fixes: bf20c69cf3cf ("usb: typec: tcpm: clear pd_event queue in PORT_RESET")
Cc: stable@vger.kernel.org
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240809112901.535072-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index cce39818e99aee75723c94be40b8cc72d98f51c0..4b02d6474259109c3ccfe662c96434f0d1ad55c2 100644 (file)
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5655,7 +5655,6 @@ static void run_state_machine(struct tcpm_port *port)
                break;
        case PORT_RESET:
                tcpm_reset_port(port);
-               port->pd_events = 0;
                if (port->self_powered)
                        tcpm_set_cc(port, TYPEC_CC_OPEN);
                else