On Fri, Aug 09, 2024 at 07:29:01PM +0800, Xu Yang wrote:
> 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@xxxxxxxxxxxxxxx
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> drivers/usb/typec/tcpm/tcpm.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index cce39818e99a..4b02d6474259 100644
> --- 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
> --
> 2.34.1
--
heikki
