| Message ID | 20220126020016.3159598-1-badhri@google.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2,1/2] usb: typec: tcpm: Do not disconnect while receiving VBUS off | expand |
On 1/25/22 18:00, 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 > 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> Why did you drop the Reviewed-by/Acked-by tags ? Guenter > --- > Changes since v1: > - Fix typos stated by Guenter Roeck. > --- > 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..3bf79f52bd34 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 reach VSAFE5V to connect */ > break; > > case SNK_NEGOTIATE_CAPABILITIES:
My bad ! Apologies .. fixing it in V3.. On Tue, Jan 25, 2022 at 7:34 PM Guenter Roeck <linux@roeck-us.net> wrote: > > On 1/25/22 18:00, 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 > > 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> > > Why did you drop the Reviewed-by/Acked-by tags ? > > Guenter > > > --- > > Changes since v1: > > - Fix typos stated by Guenter Roeck. > > --- > > 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..3bf79f52bd34 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 reach VSAFE5V to connect */ > > break; > > > > case SNK_NEGOTIATE_CAPABILITIES: >
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 59d4fa2443f2..3bf79f52bd34 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 reach 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 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> --- Changes since v1: - Fix typos stated by Guenter Roeck. --- drivers/usb/typec/tcpm/tcpm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)