| Message ID | 20210407200723.1914388-1-badhri@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/6] usb: typec: tcpm: Address incorrect values of tcpm psy for fixed supply | expand |
On Wed, Apr 07, 2021 at 01:07:18PM -0700, Badhri Jagan Sridharan wrote: > tcpm_pd_build_request overwrites current_limit and supply_voltage > even before port partner accepts the requests. This leaves stale > values in current_limit and supply_voltage that get exported by > "tcpm-source-psy-". Solving this problem by caching the request > values of current limit/supply voltage in req_current_limit > and req_supply_voltage. current_limit/supply_voltage gets updated > once the port partner accepts the request. > > Fixes: f2a8aa053c176 ("typec: tcpm: Represent source supply through power_supply") > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> > Reviewed-by: Guenter Roeck <linux@roeck-us.net> > Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > Changes since V1: > * Fixed typo as suggested by Guenter Roeck. > * Added Reviewed-by tags. > --- > drivers/usb/typec/tcpm/tcpm.c | 17 ++++++++++------- > 1 file changed, 10 insertions(+), 7 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index ca1fc77697fc..4ea4b30ae885 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -389,7 +389,10 @@ struct tcpm_port { > unsigned int operating_snk_mw; > bool update_sink_caps; > > - /* Requested current / voltage */ > + /* Requested current / voltage to the port partner */ > + u32 req_current_limit; > + u32 req_supply_voltage; > + /* Actual current / voltage limit of the local port */ > u32 current_limit; > u32 supply_voltage; > > @@ -2435,8 +2438,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > case SNK_TRANSITION_SINK: > if (port->vbus_present) { > tcpm_set_current_limit(port, > - port->current_limit, > - port->supply_voltage); > + port->req_current_limit, > + port->req_supply_voltage); > port->explicit_contract = true; > tcpm_set_auto_vbus_discharge_threshold(port, > TYPEC_PWR_MODE_PD, > @@ -2545,8 +2548,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > break; > case SNK_NEGOTIATE_PPS_CAPABILITIES: > port->pps_data.active = true; > - port->supply_voltage = port->pps_data.out_volt; > - port->current_limit = port->pps_data.op_curr; > + port->req_supply_voltage = port->pps_data.out_volt; > + port->req_current_limit = port->pps_data.op_curr; > tcpm_set_state(port, SNK_TRANSITION_SINK, 0); > break; > case SOFT_RESET_SEND: > @@ -3195,8 +3198,8 @@ static int tcpm_pd_build_request(struct tcpm_port *port, u32 *rdo) > flags & RDO_CAP_MISMATCH ? " [mismatch]" : ""); > } > > - port->current_limit = ma; > - port->supply_voltage = mv; > + port->req_current_limit = ma; > + port->req_supply_voltage = mv; > > return 0; > } > -- > 2.31.1.295.g9ea45b61b8-goog
On Wed, Apr 07, 2021 at 01:07:21PM -0700, Badhri Jagan Sridharan wrote: > >From PD Spec: > The Sink Shall transition to Sink Standby before a positive or > negative voltage transition of VBUS. During Sink Standby > the Sink Shall reduce its power draw to pSnkStdby. This allows > the Source to manage the voltage transition as well as > supply sufficient operating current to the Sink to maintain PD > operation during the transition. The Sink Shall > complete this transition to Sink Standby within tSnkStdby > after evaluating the Accept Message from the Source. The > transition when returning to Sink operation from Sink Standby > Shall be completed within tSnkNewPower. The > pSnkStdby requirement Shall only apply if the Sink power draw > is higher than this level. > > The above requirement needs to be met to prevent hard resets > from port partner. > > Without the patch: (5V/3A during SNK_DISCOVERY all the way through > explicit contract) > [ 95.711984] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > [ 95.712007] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > [ 95.712017] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > [ 95.837190] VBUS on > [ 95.882075] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > [ 95.882082] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > [ 95.882086] polarity 1 > [ 95.883151] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > [ 95.883441] enable vbus discharge ret:0 > [ 95.883445] Requesting mux state 1, usb-role 2, orientation 2 > [ 95.883776] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > [ 95.883879] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > [ 96.038960] VBUS on > [ 96.383939] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > [ 96.383946] Setting voltage/current limit 5000 mV 3000 mA > [ 96.383961] vbus=0 charge:=1 > [ 96.386044] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > [ 96.386309] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > [ 96.394404] PD RX, header: 0x2161 [1] > [ 96.394408] PDO 0: type 0, 5000 mV, 3000 mA [E] > [ 96.394410] PDO 1: type 0, 9000 mV, 2000 mA [] > [ 96.394412] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > [ 96.394416] Setting usb_comm capable false > [ 96.395083] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > [ 96.395089] Requesting PDO 1: 9000 mV, 2000 mA > [ 96.395093] PD TX, header: 0x1042 > [ 96.397404] PD TX complete, status: 0 > [ 96.397424] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > [ 96.400826] PD RX, header: 0x363 [1] > [ 96.400829] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > [ 96.400832] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > [ 96.577315] PD RX, header: 0x566 [1] > [ 96.577321] Setting voltage/current limit 9000 mV 2000 mA > [ 96.578363] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > [ 96.578370] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > > With the patch: > [ 168.398573] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > [ 168.398605] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > [ 168.398619] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > [ 168.522348] VBUS on > [ 168.568676] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > [ 168.568684] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > [ 168.568688] polarity 1 > [ 168.569867] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > [ 168.570158] enable vbus discharge ret:0 > [ 168.570161] Requesting mux state 1, usb-role 2, orientation 2 > [ 168.570504] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > [ 168.570634] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > [ 169.070689] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > [ 169.070695] Setting voltage/current limit 5000 mV 3000 mA > [ 169.070702] vbus=0 charge:=1 > [ 169.072719] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > [ 169.073145] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > [ 169.077162] PD RX, header: 0x2161 [1] > [ 169.077172] PDO 0: type 0, 5000 mV, 3000 mA [E] > [ 169.077178] PDO 1: type 0, 9000 mV, 2000 mA [] > [ 169.077183] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > [ 169.077191] Setting usb_comm capable false > [ 169.077753] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > [ 169.077759] Requesting PDO 1: 9000 mV, 2000 mA > [ 169.077762] PD TX, header: 0x1042 > [ 169.079990] PD TX complete, status: 0 > [ 169.080013] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > [ 169.083183] VBUS on > [ 169.084195] PD RX, header: 0x363 [1] > [ 169.084200] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > [ 169.084206] Setting standby current 5000 mV @ 500 mA > [ 169.084209] Setting voltage/current limit 5000 mV 500 mA > [ 169.084220] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > [ 169.260222] PD RX, header: 0x566 [1] > [ 169.260227] Setting voltage/current limit 9000 mV 2000 mA > [ 169.261315] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > [ 169.261321] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > [ 169.261570] AMS POWER_NEGOTIATION finished > > Fixes: f0690a25a140b ("staging: typec: USB Type-C Port Manager (tcpm)") > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> > --- > drivers/usb/typec/tcpm/tcpm.c | 17 +++++++++++++++++ > include/linux/usb/pd.h | 2 ++ > 2 files changed, 19 insertions(+) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index d1d03ee90d8f..770b2edd9a04 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -4131,6 +4131,23 @@ static void run_state_machine(struct tcpm_port *port) > } > break; > case SNK_TRANSITION_SINK: > + /* From the USB PD spec: > + * "The Sink Shall transition to Sink Standby before a positive or > + * negative voltage transition of VBUS. During Sink Standby > + * the Sink Shall reduce its power draw to pSnkStdby." > + * > + * This is not applicable to PPS though as the port can continue > + * to draw negotiated power without switching to standby. > + */ > + if (port->supply_voltage != port->req_supply_voltage && !port->pps_data.active && > + port->current_limit * port->supply_voltage / 1000 > PD_P_SNK_STDBY_MW) { > + u32 stdby_ma = port->supply_voltage ? PD_P_SNK_STDBY_MW * 1000 / > + port->supply_voltage : 0; Looks like unnecessary condition to me. The first condition can not be true if port->supply_voltage == 0. So I think that should be just: u32 stdby_ma = PD_P_SNK_STDBY_MW * 1000 / port->supply_voltage; Or did I miss something? > + tcpm_log(port, "Setting standby current %u mV @ %u mA", > + port->supply_voltage, stdby_ma); > + tcpm_set_current_limit(port, stdby_ma, port->supply_voltage); > + } > + fallthrough; > case SNK_TRANSITION_SINK_VBUS: > tcpm_set_state(port, hard_reset_state(port), > PD_T_PS_TRANSITION); > diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h > index 70d681918d01..bf00259493e0 100644 > --- a/include/linux/usb/pd.h > +++ b/include/linux/usb/pd.h > @@ -493,4 +493,6 @@ static inline unsigned int rdo_max_power(u32 rdo) > #define PD_N_CAPS_COUNT (PD_T_NO_RESPONSE / PD_T_SEND_SOURCE_CAP) > #define PD_N_HARD_RESET_COUNT 2 > > +#define PD_P_SNK_STDBY_MW 2500 /* 2500 mW */ > + > #endif /* __LINUX_USB_PD_H */ > -- > 2.31.1.295.g9ea45b61b8-goog thanks,
On 4/7/21 1:07 PM, Badhri Jagan Sridharan wrote: >>From PD Spec: > The Sink Shall transition to Sink Standby before a positive or > negative voltage transition of VBUS. During Sink Standby > the Sink Shall reduce its power draw to pSnkStdby. This allows > the Source to manage the voltage transition as well as > supply sufficient operating current to the Sink to maintain PD > operation during the transition. The Sink Shall > complete this transition to Sink Standby within tSnkStdby > after evaluating the Accept Message from the Source. The > transition when returning to Sink operation from Sink Standby > Shall be completed within tSnkNewPower. The > pSnkStdby requirement Shall only apply if the Sink power draw > is higher than this level. > > The above requirement needs to be met to prevent hard resets > from port partner. > > Without the patch: (5V/3A during SNK_DISCOVERY all the way through > explicit contract) > [ 95.711984] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > [ 95.712007] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > [ 95.712017] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > [ 95.837190] VBUS on > [ 95.882075] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > [ 95.882082] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > [ 95.882086] polarity 1 > [ 95.883151] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > [ 95.883441] enable vbus discharge ret:0 > [ 95.883445] Requesting mux state 1, usb-role 2, orientation 2 > [ 95.883776] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > [ 95.883879] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > [ 96.038960] VBUS on > [ 96.383939] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > [ 96.383946] Setting voltage/current limit 5000 mV 3000 mA > [ 96.383961] vbus=0 charge:=1 > [ 96.386044] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > [ 96.386309] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > [ 96.394404] PD RX, header: 0x2161 [1] > [ 96.394408] PDO 0: type 0, 5000 mV, 3000 mA [E] > [ 96.394410] PDO 1: type 0, 9000 mV, 2000 mA [] > [ 96.394412] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > [ 96.394416] Setting usb_comm capable false > [ 96.395083] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > [ 96.395089] Requesting PDO 1: 9000 mV, 2000 mA > [ 96.395093] PD TX, header: 0x1042 > [ 96.397404] PD TX complete, status: 0 > [ 96.397424] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > [ 96.400826] PD RX, header: 0x363 [1] > [ 96.400829] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > [ 96.400832] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > [ 96.577315] PD RX, header: 0x566 [1] > [ 96.577321] Setting voltage/current limit 9000 mV 2000 mA > [ 96.578363] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > [ 96.578370] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > > With the patch: > [ 168.398573] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > [ 168.398605] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > [ 168.398619] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > [ 168.522348] VBUS on > [ 168.568676] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > [ 168.568684] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > [ 168.568688] polarity 1 > [ 168.569867] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > [ 168.570158] enable vbus discharge ret:0 > [ 168.570161] Requesting mux state 1, usb-role 2, orientation 2 > [ 168.570504] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > [ 168.570634] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > [ 169.070689] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > [ 169.070695] Setting voltage/current limit 5000 mV 3000 mA > [ 169.070702] vbus=0 charge:=1 > [ 169.072719] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > [ 169.073145] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > [ 169.077162] PD RX, header: 0x2161 [1] > [ 169.077172] PDO 0: type 0, 5000 mV, 3000 mA [E] > [ 169.077178] PDO 1: type 0, 9000 mV, 2000 mA [] > [ 169.077183] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > [ 169.077191] Setting usb_comm capable false > [ 169.077753] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > [ 169.077759] Requesting PDO 1: 9000 mV, 2000 mA > [ 169.077762] PD TX, header: 0x1042 > [ 169.079990] PD TX complete, status: 0 > [ 169.080013] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > [ 169.083183] VBUS on > [ 169.084195] PD RX, header: 0x363 [1] > [ 169.084200] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > [ 169.084206] Setting standby current 5000 mV @ 500 mA > [ 169.084209] Setting voltage/current limit 5000 mV 500 mA > [ 169.084220] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > [ 169.260222] PD RX, header: 0x566 [1] > [ 169.260227] Setting voltage/current limit 9000 mV 2000 mA > [ 169.261315] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > [ 169.261321] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > [ 169.261570] AMS POWER_NEGOTIATION finished > > Fixes: f0690a25a140b ("staging: typec: USB Type-C Port Manager (tcpm)") > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > drivers/usb/typec/tcpm/tcpm.c | 17 +++++++++++++++++ > include/linux/usb/pd.h | 2 ++ > 2 files changed, 19 insertions(+) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index d1d03ee90d8f..770b2edd9a04 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -4131,6 +4131,23 @@ static void run_state_machine(struct tcpm_port *port) > } > break; > case SNK_TRANSITION_SINK: > + /* From the USB PD spec: > + * "The Sink Shall transition to Sink Standby before a positive or > + * negative voltage transition of VBUS. During Sink Standby > + * the Sink Shall reduce its power draw to pSnkStdby." > + * > + * This is not applicable to PPS though as the port can continue > + * to draw negotiated power without switching to standby. > + */ > + if (port->supply_voltage != port->req_supply_voltage && !port->pps_data.active && > + port->current_limit * port->supply_voltage / 1000 > PD_P_SNK_STDBY_MW) { > + u32 stdby_ma = port->supply_voltage ? PD_P_SNK_STDBY_MW * 1000 / > + port->supply_voltage : 0; > + tcpm_log(port, "Setting standby current %u mV @ %u mA", > + port->supply_voltage, stdby_ma); > + tcpm_set_current_limit(port, stdby_ma, port->supply_voltage); > + } > + fallthrough; > case SNK_TRANSITION_SINK_VBUS: > tcpm_set_state(port, hard_reset_state(port), > PD_T_PS_TRANSITION); > diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h > index 70d681918d01..bf00259493e0 100644 > --- a/include/linux/usb/pd.h > +++ b/include/linux/usb/pd.h > @@ -493,4 +493,6 @@ static inline unsigned int rdo_max_power(u32 rdo) > #define PD_N_CAPS_COUNT (PD_T_NO_RESPONSE / PD_T_SEND_SOURCE_CAP) > #define PD_N_HARD_RESET_COUNT 2 > > +#define PD_P_SNK_STDBY_MW 2500 /* 2500 mW */ > + > #endif /* __LINUX_USB_PD_H */ >
On Thu, Apr 8, 2021 at 12:48 AM Heikki Krogerus <heikki.krogerus@linux.intel.com> wrote: > > On Wed, Apr 07, 2021 at 01:07:21PM -0700, Badhri Jagan Sridharan wrote: > > >From PD Spec: > > The Sink Shall transition to Sink Standby before a positive or > > negative voltage transition of VBUS. During Sink Standby > > the Sink Shall reduce its power draw to pSnkStdby. This allows > > the Source to manage the voltage transition as well as > > supply sufficient operating current to the Sink to maintain PD > > operation during the transition. The Sink Shall > > complete this transition to Sink Standby within tSnkStdby > > after evaluating the Accept Message from the Source. The > > transition when returning to Sink operation from Sink Standby > > Shall be completed within tSnkNewPower. The > > pSnkStdby requirement Shall only apply if the Sink power draw > > is higher than this level. > > > > The above requirement needs to be met to prevent hard resets > > from port partner. > > > > Without the patch: (5V/3A during SNK_DISCOVERY all the way through > > explicit contract) > > [ 95.711984] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > > [ 95.712007] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > > [ 95.712017] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > > [ 95.837190] VBUS on > > [ 95.882075] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > > [ 95.882082] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > > [ 95.882086] polarity 1 > > [ 95.883151] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > > [ 95.883441] enable vbus discharge ret:0 > > [ 95.883445] Requesting mux state 1, usb-role 2, orientation 2 > > [ 95.883776] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > > [ 95.883879] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > > [ 96.038960] VBUS on > > [ 96.383939] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > > [ 96.383946] Setting voltage/current limit 5000 mV 3000 mA > > [ 96.383961] vbus=0 charge:=1 > > [ 96.386044] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > > [ 96.386309] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > > [ 96.394404] PD RX, header: 0x2161 [1] > > [ 96.394408] PDO 0: type 0, 5000 mV, 3000 mA [E] > > [ 96.394410] PDO 1: type 0, 9000 mV, 2000 mA [] > > [ 96.394412] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > > [ 96.394416] Setting usb_comm capable false > > [ 96.395083] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > > [ 96.395089] Requesting PDO 1: 9000 mV, 2000 mA > > [ 96.395093] PD TX, header: 0x1042 > > [ 96.397404] PD TX complete, status: 0 > > [ 96.397424] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > > [ 96.400826] PD RX, header: 0x363 [1] > > [ 96.400829] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > > [ 96.400832] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > > [ 96.577315] PD RX, header: 0x566 [1] > > [ 96.577321] Setting voltage/current limit 9000 mV 2000 mA > > [ 96.578363] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > > [ 96.578370] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > > > > With the patch: > > [ 168.398573] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] > > [ 168.398605] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS] > > [ 168.398619] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS] > > [ 168.522348] VBUS on > > [ 168.568676] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] > > [ 168.568684] state change SNK_DEBOUNCED -> SNK_ATTACHED [rev3 NONE_AMS] > > [ 168.568688] polarity 1 > > [ 168.569867] set_auto_vbus_discharge_threshold mode:0 pps_active:n vbus:5000 ret:0 > > [ 168.570158] enable vbus discharge ret:0 > > [ 168.570161] Requesting mux state 1, usb-role 2, orientation 2 > > [ 168.570504] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS] > > [ 168.570634] pending state change SNK_STARTUP -> SNK_DISCOVERY @ 500 ms [rev3 NONE_AMS] > > [ 169.070689] state change SNK_STARTUP -> SNK_DISCOVERY [delayed 500 ms] > > [ 169.070695] Setting voltage/current limit 5000 mV 3000 mA > > [ 169.070702] vbus=0 charge:=1 > > [ 169.072719] state change SNK_DISCOVERY -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS] > > [ 169.073145] pending state change SNK_WAIT_CAPABILITIES -> HARD_RESET_SEND @ 450 ms [rev3 NONE_AMS] > > [ 169.077162] PD RX, header: 0x2161 [1] > > [ 169.077172] PDO 0: type 0, 5000 mV, 3000 mA [E] > > [ 169.077178] PDO 1: type 0, 9000 mV, 2000 mA [] > > [ 169.077183] state change SNK_WAIT_CAPABILITIES -> SNK_NEGOTIATE_CAPABILITIES [rev2 POWER_NEGOTIATION] > > [ 169.077191] Setting usb_comm capable false > > [ 169.077753] cc=0 cc1=0 cc2=5 vbus=0 vconn=sink polarity=1 > > [ 169.077759] Requesting PDO 1: 9000 mV, 2000 mA > > [ 169.077762] PD TX, header: 0x1042 > > [ 169.079990] PD TX complete, status: 0 > > [ 169.080013] pending state change SNK_NEGOTIATE_CAPABILITIES -> HARD_RESET_SEND @ 60 ms [rev2 POWER_NEGOTIATION] > > [ 169.083183] VBUS on > > [ 169.084195] PD RX, header: 0x363 [1] > > [ 169.084200] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_TRANSITION_SINK [rev2 POWER_NEGOTIATION] > > [ 169.084206] Setting standby current 5000 mV @ 500 mA > > [ 169.084209] Setting voltage/current limit 5000 mV 500 mA > > [ 169.084220] pending state change SNK_TRANSITION_SINK -> HARD_RESET_SEND @ 500 ms [rev2 POWER_NEGOTIATION] > > [ 169.260222] PD RX, header: 0x566 [1] > > [ 169.260227] Setting voltage/current limit 9000 mV 2000 mA > > [ 169.261315] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:9000 ret:0 > > [ 169.261321] state change SNK_TRANSITION_SINK -> SNK_READY [rev2 POWER_NEGOTIATION] > > [ 169.261570] AMS POWER_NEGOTIATION finished > > > > Fixes: f0690a25a140b ("staging: typec: USB Type-C Port Manager (tcpm)") > > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> > > --- > > drivers/usb/typec/tcpm/tcpm.c | 17 +++++++++++++++++ > > include/linux/usb/pd.h | 2 ++ > > 2 files changed, 19 insertions(+) > > > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > > index d1d03ee90d8f..770b2edd9a04 100644 > > --- a/drivers/usb/typec/tcpm/tcpm.c > > +++ b/drivers/usb/typec/tcpm/tcpm.c > > @@ -4131,6 +4131,23 @@ static void run_state_machine(struct tcpm_port *port) > > } > > break; > > case SNK_TRANSITION_SINK: > > + /* From the USB PD spec: > > + * "The Sink Shall transition to Sink Standby before a positive or > > + * negative voltage transition of VBUS. During Sink Standby > > + * the Sink Shall reduce its power draw to pSnkStdby." > > + * > > + * This is not applicable to PPS though as the port can continue > > + * to draw negotiated power without switching to standby. > > + */ > > + if (port->supply_voltage != port->req_supply_voltage && !port->pps_data.active && > > + port->current_limit * port->supply_voltage / 1000 > PD_P_SNK_STDBY_MW) { > > + u32 stdby_ma = port->supply_voltage ? PD_P_SNK_STDBY_MW * 1000 / > > + port->supply_voltage : 0; > > Looks like unnecessary condition to me. The first condition can not be > true if port->supply_voltage == 0. So I think that should be just: > > u32 stdby_ma = PD_P_SNK_STDBY_MW * 1000 / port->supply_voltage; > > Or did I miss something? You are right. That's indeed not necessary. I was wondering whether port->supply_voltage would be 0 during the swap sequence. It doesn't seem to be. Updating in my next version - V3. Thanks Heikki ! > > > + tcpm_log(port, "Setting standby current %u mV @ %u mA", > > + port->supply_voltage, stdby_ma); > > + tcpm_set_current_limit(port, stdby_ma, port->supply_voltage); > > + } > > + fallthrough; > > case SNK_TRANSITION_SINK_VBUS: > > tcpm_set_state(port, hard_reset_state(port), > > PD_T_PS_TRANSITION); > > diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h > > index 70d681918d01..bf00259493e0 100644 > > --- a/include/linux/usb/pd.h > > +++ b/include/linux/usb/pd.h > > @@ -493,4 +493,6 @@ static inline unsigned int rdo_max_power(u32 rdo) > > #define PD_N_CAPS_COUNT (PD_T_NO_RESPONSE / PD_T_SEND_SOURCE_CAP) > > #define PD_N_HARD_RESET_COUNT 2 > > > > +#define PD_P_SNK_STDBY_MW 2500 /* 2500 mW */ > > + > > #endif /* __LINUX_USB_PD_H */ > > -- > > 2.31.1.295.g9ea45b61b8-goog > > thanks, > > -- > heikki
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index ca1fc77697fc..4ea4b30ae885 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -389,7 +389,10 @@ struct tcpm_port { unsigned int operating_snk_mw; bool update_sink_caps; - /* Requested current / voltage */ + /* Requested current / voltage to the port partner */ + u32 req_current_limit; + u32 req_supply_voltage; + /* Actual current / voltage limit of the local port */ u32 current_limit; u32 supply_voltage; @@ -2435,8 +2438,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, case SNK_TRANSITION_SINK: if (port->vbus_present) { tcpm_set_current_limit(port, - port->current_limit, - port->supply_voltage); + port->req_current_limit, + port->req_supply_voltage); port->explicit_contract = true; tcpm_set_auto_vbus_discharge_threshold(port, TYPEC_PWR_MODE_PD, @@ -2545,8 +2548,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, break; case SNK_NEGOTIATE_PPS_CAPABILITIES: port->pps_data.active = true; - port->supply_voltage = port->pps_data.out_volt; - port->current_limit = port->pps_data.op_curr; + port->req_supply_voltage = port->pps_data.out_volt; + port->req_current_limit = port->pps_data.op_curr; tcpm_set_state(port, SNK_TRANSITION_SINK, 0); break; case SOFT_RESET_SEND: @@ -3195,8 +3198,8 @@ static int tcpm_pd_build_request(struct tcpm_port *port, u32 *rdo) flags & RDO_CAP_MISMATCH ? " [mismatch]" : ""); } - port->current_limit = ma; - port->supply_voltage = mv; + port->req_current_limit = ma; + port->req_supply_voltage = mv; return 0; }
tcpm_pd_build_request overwrites current_limit and supply_voltage even before port partner accepts the requests. This leaves stale values in current_limit and supply_voltage that get exported by "tcpm-source-psy-". Solving this problem by caching the request values of current limit/supply voltage in req_current_limit and req_supply_voltage. current_limit/supply_voltage gets updated once the port partner accepts the request. Fixes: f2a8aa053c176 ("typec: tcpm: Represent source supply through power_supply") Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> --- Changes since V1: * Fixed typo as suggested by Guenter Roeck. * Added Reviewed-by tags. --- drivers/usb/typec/tcpm/tcpm.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-)