| Message ID | 20220122015520.332507-1-badhri@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v1,1/2] usb: typec: tcpm: Do not disconnect while receiving VBUS off | expand |
On 1/21/22 17:55, Badhri Jagan Sridharan wrote: > With some chargers, vbus might momentarily raise above VSAFE5V and fall > back to 0V before tcpm gets to read port->tcpc->get_vbus. This will > will report a VBUS off event causing TCPM to transition to s/will will/will/ > SNK_UNATTACHED where it should be waiting in either SNK_ATTACH_WAIT > or SNK_DEBOUNCED state. This patch makes TCPM avoid vbus off events > while in SNK_ATTACH_WAIT or SNK_DEBOUNCED state. > > Stub from the spec: > "4.5.2.2.4.2 Exiting from AttachWait.SNK State > A Sink shall transition to Unattached.SNK when the state of both > the CC1 and CC2 pins is SNK.Open for at least tPDDebounce. > A DRP shall transition to Unattached.SRC when the state of both > the CC1 and CC2 pins is SNK.Open for at least tPDDebounce." > > [23.194131] CC1: 0 -> 0, CC2: 0 -> 5 [state SNK_UNATTACHED, polarity 0, connected] > [23.201777] state change SNK_UNATTACHED -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > [23.209949] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > [23.300579] VBUS off > [23.300668] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [rev3 NONE_AMS] > [23.301014] VBUS VSAFE0V > [23.301111] Start toggling > > Fixes: f0690a25a140b8 ("staging: typec: USB Type-C Port Manager (tcpm)") > Cc: stable@vger.kernel.org > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> > --- > drivers/usb/typec/tcpm/tcpm.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index 59d4fa2443f2..b8afe3d8c882 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -5156,7 +5156,8 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) > case SNK_TRYWAIT_DEBOUNCE: > break; > case SNK_ATTACH_WAIT: > - tcpm_set_state(port, SNK_UNATTACHED, 0); > + case SNK_DEBOUNCED: > + /* Do nothing, as TCPM is still waiting for vbus to reaach VSAFE5V to connect */ s/reaach/reach/ Other than that, Reviewed-by: Guenter Roeck <linux@roeck-us.net> > break; > > case SNK_NEGOTIATE_CAPABILITIES:
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 59d4fa2443f2..b8afe3d8c882 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -5156,7 +5156,8 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) case SNK_TRYWAIT_DEBOUNCE: break; case SNK_ATTACH_WAIT: - tcpm_set_state(port, SNK_UNATTACHED, 0); + case SNK_DEBOUNCED: + /* Do nothing, as TCPM is still waiting for vbus to reaach VSAFE5V to connect */ break; case SNK_NEGOTIATE_CAPABILITIES:
With some chargers, vbus might momentarily raise above VSAFE5V and fall back to 0V before tcpm gets to read port->tcpc->get_vbus. This will will report a VBUS off event causing TCPM to transition to SNK_UNATTACHED where it should be waiting in either SNK_ATTACH_WAIT or SNK_DEBOUNCED state. This patch makes TCPM avoid vbus off events while in SNK_ATTACH_WAIT or SNK_DEBOUNCED state. Stub from the spec: "4.5.2.2.4.2 Exiting from AttachWait.SNK State A Sink shall transition to Unattached.SNK when the state of both the CC1 and CC2 pins is SNK.Open for at least tPDDebounce. A DRP shall transition to Unattached.SRC when the state of both the CC1 and CC2 pins is SNK.Open for at least tPDDebounce." [23.194131] CC1: 0 -> 0, CC2: 0 -> 5 [state SNK_UNATTACHED, polarity 0, connected] [23.201777] state change SNK_UNATTACHED -> SNK_ATTACH_WAIT [rev3 NONE_AMS] [23.209949] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] [23.300579] VBUS off [23.300668] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [rev3 NONE_AMS] [23.301014] VBUS VSAFE0V [23.301111] Start toggling Fixes: f0690a25a140b8 ("staging: typec: USB Type-C Port Manager (tcpm)") Cc: stable@vger.kernel.org Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> --- drivers/usb/typec/tcpm/tcpm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)