Yes I did ! https://lkml.org/lkml/2020/8/11/788 ! For me gmail is grouping V1 and V2 patches in the same thread so thought you saw the v2 patch :P Thanks, Badhri On Tue, Aug 11, 2020 at 5:36 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > On 8/11/20 4:21 PM, Badhri Jagan Sridharan wrote: > > Thanks Guenter ! However I don't see a reviewed-by tag :) > > > > Confused. Did you send a v2 with the changes we discussed ? > I didn't see that. > > Thanks, > Guenter > > > On Tue, Aug 11, 2020 at 1:18 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > >> > >> On 8/11/20 12:39 PM, Badhri Jagan Sridharan wrote: > >>> On Tue, Aug 11, 2020 at 11:45 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > >>>> > >>>> On Tue, Aug 11, 2020 at 11:24:07AM -0700, Badhri Jagan Sridharan wrote: > >>>>> On Mon, Aug 10, 2020 at 6:51 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > >>>>>> > >>>>>> On 8/10/20 6:11 PM, Badhri Jagan Sridharan wrote: > >>>>>>> >From the spec: > >>>>>>> "7.1.5 Response to Hard Resets > >>>>>>> Hard Reset Signaling indicates a communication failure has occurred and > >>>>>>> the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin > >>>>>>> and Shall drive VBUS to vSafe0V as shown in Figure 7-9. The USB connection > >>>>>>> May reset during a Hard Reset since the VBUS voltage will be less than > >>>>>>> vSafe5V for an extended period of time. After establishing the vSafe0V > >>>>>>> voltage condition on VBUS, the Source Shall wait tSrcRecover before > >>>>>>> re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform > >>>>>>> to the VCONN timing as specified in [USB Type-C 1.3]." > >>>>>>> > >>>>>>> Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx> > >>>>>>> --- > >>>>>>> drivers/usb/typec/tcpm/tcpm.c | 16 +++++++++++++--- > >>>>>>> 1 file changed, 13 insertions(+), 3 deletions(-) > >>>>>>> > >>>>>>> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> index 3ef37202ee37..e41c4e5d3c71 100644 > >>>>>>> --- a/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> +++ b/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> @@ -3372,13 +3372,19 @@ static void run_state_machine(struct tcpm_port *port) > >>>>>>> tcpm_set_state(port, SNK_HARD_RESET_SINK_OFF, 0); > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_OFF: > >>>>>>> - tcpm_set_vconn(port, true); > >>>>>>> + /* > >>>>>>> + * 7.1.5 Response to Hard Resets > >>>>>>> + * Hard Reset Signaling indicates a communication failure has occurred and the > >>>>>>> + * Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall > >>>>>>> + * drive VBUS to vSafe0V as shown in Figure 7-9. > >>>>>>> + */ > >>>>>>> + tcpm_set_vconn(port, false); > >>>>>>> tcpm_set_vbus(port, false); > >>>>>>> tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE, > >>>>>>> tcpm_data_role_for_source(port)); > >>>>>>> - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); > >>>>>> > >>>>>> I am a bit concerned about this. If I understand correctly, it means that > >>>>>> we won't turn VBUS back on unless a SRC_HARD_RESET_VBUS_OFF PD event is received. > >>>>>> Is that correct ? What happens if that event is never received ? > >>>>>> > >>>>>> Thanks, > >>>>>> Guenter > >>>>> > >>>>> The term PD event is a little ambiguous to me. Trying to summarize the workflow. > >>>>> Lower level tcpc driver would have to call tcpm_vbus_change which > >>>>> would in-turn trigger TCPM_VBUS_EVENT > >>>>> and queries port->tcpc->get_vbus to get the vbus status. It is not > >>>>> really a PD protocol driven event hence the > >>>>> confusion. > >>>>> > >>>>> "What happens if that event is never received ?" > >>>>> Yeah TCPM would be in SRC_HARD_RESET_VBUS_OFF till the tcpc calls the > >>>>> tcpm_vbus_change. > >>>>> Do you suspect that existing tcpc would not have the capability to > >>>>> monitor vbus status while sourcing and call tcpm_vbus_change? > >>>>> > >>>> That, or the driver might be buggy, or the hardware does't signal a status > >>>> update, or the update gets lost. I think we should have some backup, > >>>> to trigger if the event is not received in a reasonable amout of time. > >>>> I don't know if the specification has some kind of maximum limit. If > >>>> not, we should still have something > >>>> > >>>> Thanks, > >>>> Guenter > >>> > >>> Got it ! The specification actually has a bound for vbus off. > >>> tSafe0V - Time to reach vSafe0V max - 650ms. (PD_T_SAFE_0V). > >>> So I will bound it to that. > >>> > >> > >> Excellent. Thanks a lot for looking into this! > >> > >> Guenter > >> > >>> >From Table 7-12 Sequence Description for a Source Initiated Hard Reset: > >>> 4.Policy Engine waits tPSHardReset after sending Hard Reset Signaling > >>> and then tells the Device Policy Manager to instruct the power supply > >>> to perform a Hard Reset. The transition to vSafe0V Shall occur within > >>> tSafe0V (t2). > >>> 5 After tSrcRecover the Source applies power to VBUS in an attempt to > >>> re-establish communication with the Sink and resume USB Default > >>> Operation. The transition to vSafe5V Shall occur within tSrcTurnOn > >>> (t4). > >>> > >>> Thanks, > >>> Badhri > >>> > >>>> > >>>>> Thanks, > >>>>> Badhri > >>>>> > >>>>> > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_ON: > >>>>>>> + tcpm_set_vconn(port, true); > >>>>>>> tcpm_set_vbus(port, true); > >>>>>>> port->tcpc->set_pd_rx(port->tcpc, true); > >>>>>>> tcpm_set_attached_state(port, true); > >>>>>>> @@ -3944,7 +3950,11 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) > >>>>>>> tcpm_set_state(port, SNK_HARD_RESET_WAIT_VBUS, 0); > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_OFF: > >>>>>>> - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, 0); > >>>>>>> + /* > >>>>>>> + * After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait > >>>>>>> + * tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. > >>>>>>> + */ > >>>>>>> + tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); > >>>>>>> break; > >>>>>>> case HARD_RESET_SEND: > >>>>>>> break; > >>>>>>> > >>>>>> > >> >
