Hi Ondřej, > > Hi, > > On Sun, Aug 20, 2023 at 11:15:18PM +0800, Xu Yang wrote: > > The try_src_count and try_snk_count may still be 1 after enter into > > unattached state. This may be caused by below case: > > - SNK_TRY->SNK_TRY_WAIT->SRC_TRYWAIT->SNK_UNATTACHED > > - SRC_TRY->SRC_TRY_WAIT->SNK_TRYWAIT->SNK_UNATTACHED > > > > The port->attached is not true at the end and tcpm_reset_port() will not > > be called. This will reset counter into for these cases, otherwise the tcpm > > won't try role when new cable attached. > > > > Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx> > > --- > > drivers/usb/typec/tcpm/tcpm.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > > index 5639b9a1e0bf..c9a186a8c58c 100644 > > --- a/drivers/usb/typec/tcpm/tcpm.c > > +++ b/drivers/usb/typec/tcpm/tcpm.c > > @@ -3719,6 +3719,9 @@ static void tcpm_detach(struct tcpm_port *port) > > if (tcpm_port_is_disconnected(port)) > > port->hard_reset_count = 0; > > > > + port->try_src_count = 0; > > + port->try_snk_count = 0; > > This patch breaks partner detection for USB type-c hubs and USB type-c docks. I guess the type-c port of hub is sink-only and the type-c port of dock is DRP, right? > > Connecting an unpowered USB-C 4-port HUB: > > Before reverting this patch: (endless loop) > > [ 0.657246] Setting usb_comm capable false > [ 0.661870] Setting voltage/current limit 0 mV 0 mA > [ 0.661880] polarity 0 > [ 0.661883] Requesting mux state 0, usb-role 0, orientation 0 > [ 0.663879] state change INVALID_STATE -> SNK_UNATTACHED [rev1 NONE_AMS] > [ 0.663891] CC1: 0 -> 0, CC2: 0 -> 0 [state SNK_UNATTACHED, polarity 0, disconnected] > [ 0.663897] 4-0022: registered > [ 0.663962] Setting usb_comm capable false > [ 0.669903] Setting voltage/current limit 0 mV 0 mA > [ 0.669914] polarity 0 > [ 0.669917] Requesting mux state 0, usb-role 0, orientation 0 > [ 0.672166] cc:=2 > [ 0.679360] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev1 NONE_AMS] > [ 0.779554] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms] > [ 0.779570] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev1 NONE_AMS] > [ 0.779576] Start toggling > [ 12.957711] CC1: 0 -> 0, CC2: 0 -> 2 [state TOGGLING, polarity 0, connected] > [ 12.957720] state change TOGGLING -> SRC_ATTACH_WAIT [rev1 NONE_AMS] > [ 12.957729] pending state change SRC_ATTACH_WAIT -> SNK_TRY @ 200 ms [rev1 NONE_AMS] > [ 13.157924] state change SRC_ATTACH_WAIT -> SNK_TRY [delayed 200 ms] > [ 13.157939] cc:=2 > [ 13.167339] pending state change SNK_TRY -> SNK_TRY_WAIT @ 100 ms [rev1 NONE_AMS] > [ 13.267545] state change SNK_TRY -> SNK_TRY_WAIT [delayed 100 ms] > [ 13.267561] state change SNK_TRY_WAIT -> SRC_TRYWAIT [rev1 NONE_AMS] > [ 13.267566] cc:=3 > [ 13.278148] pending state change SRC_TRYWAIT -> SRC_TRYWAIT_UNATTACHED @ 100 ms [rev1 NONE_AMS] Based on my assumption, the DRP port is presenting Rp-default termination on CC line again, then tcpc should report CC change due to a connection is established in 100 ms. However, this CC change is not reported here. This leads to state from SRC_TRYWAIT to SRC_TRYWAIT_UNATTACHED rather SRC_TRYWAIT_DEBOUNCE. Below log is a normal case. --- [ 149.954434] CC1: 0 -> 0, CC2: 0 -> 2 [state TOGGLING, polarity 0, connected] [ 149.954447] state change TOGGLING -> SRC_ATTACH_WAIT [rev1 NONE_AMS] [ 149.954452] pending state change SRC_ATTACH_WAIT -> SNK_TRY @ 200 ms [rev1 NONE_AMS] [ 150.154543] state change SRC_ATTACH_WAIT -> SNK_TRY [delayed 200 ms] [ 150.154554] cc:=2 [ 150.154859] pending state change SNK_TRY -> SNK_TRY_WAIT @ 100 ms [rev1 NONE_AMS] [ 150.254881] state change SNK_TRY -> SNK_TRY_WAIT [delayed 100 ms] [ 150.254893] state change SNK_TRY_WAIT -> SRC_TRYWAIT [rev1 NONE_AMS] [ 150.254896] cc:=3 [ 150.255200] pending state change SRC_TRYWAIT -> SRC_TRYWAIT_UNATTACHED @ 100 ms [rev1 NONE_AMS] [ 150.257288] CC1: 0 -> 0, CC2: 2 -> 2 [state SRC_TRYWAIT, polarity 0, connected] [ 150.257295] state change SRC_TRYWAIT -> SRC_TRYWAIT_DEBOUNCE [rev1 NONE_AMS] [ 150.257300] pending state change SRC_TRYWAIT_DEBOUNCE -> SRC_ATTACHED @ 200 ms [rev1 NONE_AMS] [ 150.457319] state change SRC_TRYWAIT_DEBOUNCE -> SRC_ATTACHED [delayed 200 ms] [ 150.457329] cc:=3 [ 150.457606] polarity 1 [ 150.458314] Requesting mux state 1, usb-role 1, orientation 2 [ 150.460722] vbus:=1 charge=0 --- So the issue may be why that CC change is not reported? Please refer to USB Type-C Specification Figure 4-17 Connection State Diagram: DRP with Accessory and Try.SNK Support Thanks, Xu Yang > [ 13.378347] state change SRC_TRYWAIT -> SRC_TRYWAIT_UNATTACHED [delayed 100 ms] > [ 13.378364] state change SRC_TRYWAIT_UNATTACHED -> SNK_UNATTACHED [rev1 NONE_AMS] > [ 13.378373] Start toggling > [ 13.387019] state change SNK_UNATTACHED -> TOGGLING [rev1 NONE_AMS] > [ 13.462597] CC1: 0 -> 0, CC2: 2 -> 2 [state TOGGLING, polarity 0, connected] > [ 13.462606] state change TOGGLING -> SRC_ATTACH_WAIT [rev1 NONE_AMS] > [ 13.462613] pending state change SRC_ATTACH_WAIT -> SNK_TRY @ 200 ms [rev1 NONE_AMS] > [ 13.662808] state change SRC_ATTACH_WAIT -> SNK_TRY [delayed 200 ms] > [ 13.662827] cc:=2
