| Message ID | 20210517192112.40934-3-badhri@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/4] usb: typec: tcpm: Fix up PR_SWAP when vsafe0v is signalled | expand |
On Mon, May 17, 2021 at 12:21:11PM -0700, Badhri Jagan Sridharan wrote: > When vbus auto discharge is enabled, TCPCI based TCPC transitions > into Attached.SNK/Attached.SRC state. During PR_SWAP, TCPCI based > TCPC would disconnect when partner changes power roles. TCPC has > to be moved APPLY RC state during PR_SWAP. This is done by > ROLE_CONTROL.CC1 != ROLE_CONTROL.CC2 and > POWER_CONTROL.AutodischargeDisconnect is 0. Once the swap sequence > is done, AutoDischargeDisconnect is re-enabled. > > Fixes: f321a02caebd ("usb: typec: tcpm: Implement enabling Auto Discharge disconnect support") > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > Changes since v1: > - Added additional check port->tcpc->apply_rc as suggested by Guenter > Roeck > --- > drivers/usb/typec/tcpm/tcpm.c | 16 ++++++++++++++++ > include/linux/usb/tcpm.h | 4 ++++ > 2 files changed, 20 insertions(+) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index b475d9b9d38d..3c2cade986c9 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -786,6 +786,19 @@ static int tcpm_enable_auto_vbus_discharge(struct tcpm_port *port, bool enable) > return ret; > } > > +static void tcpm_apply_rc(struct tcpm_port *port) > +{ > + /* > + * TCPCI: Move to APPLY_RC state to prevent disconnect during PR_SWAP > + * when Vbus auto discharge on disconnect is enabled. > + */ > + if (port->tcpc->enable_auto_vbus_discharge && port->tcpc->apply_rc) { > + tcpm_log(port, "Apply_RC"); > + port->tcpc->apply_rc(port->tcpc, port->cc_req, port->polarity); > + tcpm_enable_auto_vbus_discharge(port, false); > + } > +} > + > /* > * Determine RP value to set based on maximum current supported > * by a port if configured as source. > @@ -4428,6 +4441,7 @@ static void run_state_machine(struct tcpm_port *port) > tcpm_set_state(port, ready_state(port), 0); > break; > case PR_SWAP_START: > + tcpm_apply_rc(port); > if (port->pwr_role == TYPEC_SOURCE) > tcpm_set_state(port, PR_SWAP_SRC_SNK_TRANSITION_OFF, > PD_T_SRC_TRANSITION); > @@ -4467,6 +4481,7 @@ static void run_state_machine(struct tcpm_port *port) > tcpm_set_state(port, ERROR_RECOVERY, PD_T_PS_SOURCE_ON_PRS); > break; > case PR_SWAP_SRC_SNK_SINK_ON: > + tcpm_enable_auto_vbus_discharge(port, true); > /* Set the vbus disconnect threshold for implicit contract */ > tcpm_set_auto_vbus_discharge_threshold(port, TYPEC_PWR_MODE_USB, false, VSAFE5V); > tcpm_set_state(port, SNK_STARTUP, 0); > @@ -4483,6 +4498,7 @@ static void run_state_machine(struct tcpm_port *port) > PD_T_PS_SOURCE_OFF); > break; > case PR_SWAP_SNK_SRC_SOURCE_ON: > + tcpm_enable_auto_vbus_discharge(port, true); > tcpm_set_cc(port, tcpm_rp_cc(port)); > tcpm_set_vbus(port, true); > /* > diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h > index 42fcfbe10590..bffc8d3e14ad 100644 > --- a/include/linux/usb/tcpm.h > +++ b/include/linux/usb/tcpm.h > @@ -66,6 +66,8 @@ enum tcpm_transmit_type { > * For example, some tcpcs may include BC1.2 charger detection > * and use that in this case. > * @set_cc: Called to set value of CC pins > + * @apply_rc: Optional; Needed to move TCPCI based chipset to APPLY_RC state > + * as stated by the TCPCI specification. > * @get_cc: Called to read current CC pin values > * @set_polarity: > * Called to set polarity > @@ -120,6 +122,8 @@ struct tcpc_dev { > int (*get_vbus)(struct tcpc_dev *dev); > int (*get_current_limit)(struct tcpc_dev *dev); > int (*set_cc)(struct tcpc_dev *dev, enum typec_cc_status cc); > + int (*apply_rc)(struct tcpc_dev *dev, enum typec_cc_status cc, > + enum typec_cc_polarity polarity); > int (*get_cc)(struct tcpc_dev *dev, enum typec_cc_status *cc1, > enum typec_cc_status *cc2); > int (*set_polarity)(struct tcpc_dev *dev, > -- > 2.31.1.751.gd2f1c929bd-goog
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index b475d9b9d38d..3c2cade986c9 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -786,6 +786,19 @@ static int tcpm_enable_auto_vbus_discharge(struct tcpm_port *port, bool enable) return ret; } +static void tcpm_apply_rc(struct tcpm_port *port) +{ + /* + * TCPCI: Move to APPLY_RC state to prevent disconnect during PR_SWAP + * when Vbus auto discharge on disconnect is enabled. + */ + if (port->tcpc->enable_auto_vbus_discharge && port->tcpc->apply_rc) { + tcpm_log(port, "Apply_RC"); + port->tcpc->apply_rc(port->tcpc, port->cc_req, port->polarity); + tcpm_enable_auto_vbus_discharge(port, false); + } +} + /* * Determine RP value to set based on maximum current supported * by a port if configured as source. @@ -4428,6 +4441,7 @@ static void run_state_machine(struct tcpm_port *port) tcpm_set_state(port, ready_state(port), 0); break; case PR_SWAP_START: + tcpm_apply_rc(port); if (port->pwr_role == TYPEC_SOURCE) tcpm_set_state(port, PR_SWAP_SRC_SNK_TRANSITION_OFF, PD_T_SRC_TRANSITION); @@ -4467,6 +4481,7 @@ static void run_state_machine(struct tcpm_port *port) tcpm_set_state(port, ERROR_RECOVERY, PD_T_PS_SOURCE_ON_PRS); break; case PR_SWAP_SRC_SNK_SINK_ON: + tcpm_enable_auto_vbus_discharge(port, true); /* Set the vbus disconnect threshold for implicit contract */ tcpm_set_auto_vbus_discharge_threshold(port, TYPEC_PWR_MODE_USB, false, VSAFE5V); tcpm_set_state(port, SNK_STARTUP, 0); @@ -4483,6 +4498,7 @@ static void run_state_machine(struct tcpm_port *port) PD_T_PS_SOURCE_OFF); break; case PR_SWAP_SNK_SRC_SOURCE_ON: + tcpm_enable_auto_vbus_discharge(port, true); tcpm_set_cc(port, tcpm_rp_cc(port)); tcpm_set_vbus(port, true); /* diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h index 42fcfbe10590..bffc8d3e14ad 100644 --- a/include/linux/usb/tcpm.h +++ b/include/linux/usb/tcpm.h @@ -66,6 +66,8 @@ enum tcpm_transmit_type { * For example, some tcpcs may include BC1.2 charger detection * and use that in this case. * @set_cc: Called to set value of CC pins + * @apply_rc: Optional; Needed to move TCPCI based chipset to APPLY_RC state + * as stated by the TCPCI specification. * @get_cc: Called to read current CC pin values * @set_polarity: * Called to set polarity @@ -120,6 +122,8 @@ struct tcpc_dev { int (*get_vbus)(struct tcpc_dev *dev); int (*get_current_limit)(struct tcpc_dev *dev); int (*set_cc)(struct tcpc_dev *dev, enum typec_cc_status cc); + int (*apply_rc)(struct tcpc_dev *dev, enum typec_cc_status cc, + enum typec_cc_polarity polarity); int (*get_cc)(struct tcpc_dev *dev, enum typec_cc_status *cc1, enum typec_cc_status *cc2); int (*set_polarity)(struct tcpc_dev *dev,
When vbus auto discharge is enabled, TCPCI based TCPC transitions into Attached.SNK/Attached.SRC state. During PR_SWAP, TCPCI based TCPC would disconnect when partner changes power roles. TCPC has to be moved APPLY RC state during PR_SWAP. This is done by ROLE_CONTROL.CC1 != ROLE_CONTROL.CC2 and POWER_CONTROL.AutodischargeDisconnect is 0. Once the swap sequence is done, AutoDischargeDisconnect is re-enabled. Fixes: f321a02caebd ("usb: typec: tcpm: Implement enabling Auto Discharge disconnect support") Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> --- Changes since v1: - Added additional check port->tcpc->apply_rc as suggested by Guenter Roeck --- drivers/usb/typec/tcpm/tcpm.c | 16 ++++++++++++++++ include/linux/usb/tcpm.h | 4 ++++ 2 files changed, 20 insertions(+)