On Sun, Aug 20, 2023 at 04:44:48AM +0000, Badhri Jagan Sridharan wrote: > When partner does not support get_status message, tcpm right now > responds with soft reset message. This causes PD renegotiation to > happen and resets PPS link. Avoid soft resetting the link when > partner does not support get_status message to mitigate PPS resets. > > [ 208.926752] Setting voltage/current limit 9500 mV 2450 mA > [ 208.930407] set_auto_vbus_discharge_threshold mode:3 pps_active:y vbus:9500 ret:0 > [ 208.930418] state change SNK_TRANSITION_SINK -> SNK_READY [rev3 POWER_NEGOTIATION] > [ 208.930455] AMS POWER_NEGOTIATION finished > > // ALERT message from the Source > [ 213.948442] PD RX, header: 0x19a6 [1] > [ 213.948451] state change SNK_READY -> GET_STATUS_SEND [rev3 GETTING_SOURCE_SINK_STATUS] > [ 213.948457] PD TX, header: 0x492 > [ 213.950402] PD TX complete, status: 0 > [ 213.950427] pending state change GET_STATUS_SEND -> GET_STATUS_SEND_TIMEOUT @ 60 ms [rev3 GETTING_SOURCE_SINK_STATUS] > > // NOT_SUPPORTED from the Source > [ 213.959954] PD RX, header: 0xbb0 [1] > > // sink sends SOFT_RESET > [ 213.959958] state change GET_STATUS_SEND -> SNK_SOFT_RESET [rev3 GETTING_SOURCE_SINK_STATUS] > [ 213.959962] AMS GETTING_SOURCE_SINK_STATUS finished > [ 213.959964] AMS SOFT_RESET_AMS start > [ 213.959966] state change SNK_SOFT_RESET -> AMS_START [rev3 SOFT_RESET_AMS] > [ 213.959969] state change AMS_START -> SOFT_RESET_SEND [rev3 SOFT_RESET_AMS] > > Cc: stable@xxxxxxxxxxxxxxx > Fixes: 8dea75e11380 ("usb: typec: tcpm: Protocol Error handling") > Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx> Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > --- > 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 5639b9a1e0bf..280ce1bd7b53 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -2753,6 +2753,13 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > port->sink_cap_done = true; > tcpm_set_state(port, ready_state(port), 0); > break; > + /* > + * Some port partners do not support GET_STATUS, avoid soft reset the link to > + * prevent redundant power re-negotiation > + */ > + case GET_STATUS_SEND: > + tcpm_set_state(port, ready_state(port), 0); > + break; > case SRC_READY: > case SNK_READY: > if (port->vdm_state > VDM_STATE_READY) { > > base-commit: bbb9e06d2c6435af9c62074ad7048910eeb2e7bc > -- > 2.42.0.rc1.204.g551eb34607-goog -- heikki