Messages in this thread Patch in this message | | | From | Guenter Roeck <> | Subject | Re: [PATCH v2 2/2] usb: typec: tcpm: Support non-PD mode | Date | Tue, 27 Jul 2021 15:46:54 -0700 |
| |
On 7/27/21 8:13 AM, Kyle Tso wrote: > Even if the Type-C controller supports PD, it is doable to disable PD > capabilities with the current state machine in TCPM. Without enabling RX > in low-level drivers and with skipping the power negotiation, the port > is eligible to be a non-PD Type-C port. Use new flags whose values are > populated from the device tree to decide the port PD capability. Adding > "pd-supported" property in device tree indicates that the port supports > PD. If "pd-supported" is not found, "typec-power-opmode" shall be added > to specify the advertised Rp value if the port supports SRC role. > > Signed-off-by: Kyle Tso <kyletso@google.com> > --- > changes since v1: > - Revised the patch to use dt properties > - Added back the checks of callbacks set_pd_rx and pd_transmit > - Added src_rp to indicate which Rp value should be used in SRC. This > variable is derived from dt property "typec-power-opmode" > > drivers/usb/typec/tcpm/tcpm.c | 108 +++++++++++++++++++++++++--------- > 1 file changed, 79 insertions(+), 29 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index 5b22a1c931a9..4cf77c787f54 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -316,6 +316,7 @@ struct tcpm_port { > struct typec_partner *partner; > > enum typec_cc_status cc_req; > + enum typec_cc_status src_rp; /* work only if pd_supported == false */ > > enum typec_cc_status cc1; > enum typec_cc_status cc2; > @@ -323,6 +324,7 @@ struct tcpm_port { > > bool attached; > bool connected; > + bool pd_supported; > enum typec_port_type port_type; > > /* > @@ -804,6 +806,7 @@ static void tcpm_apply_rc(struct tcpm_port *port) > } > } > > + > /* > * Determine RP value to set based on maximum current supported > * by a port if configured as source. > @@ -815,6 +818,9 @@ static enum typec_cc_status tcpm_rp_cc(struct tcpm_port *port) > int nr_pdo = port->nr_src_pdo; > int i; > > + if (!port->pd_supported) > + return port->src_rp; > + > /* > * Search for first entry with matching voltage. > * It should report the maximum supported current. > @@ -3568,9 +3574,11 @@ static int tcpm_src_attach(struct tcpm_port *port) > if (ret < 0) > return ret; > > - ret = port->tcpc->set_pd_rx(port->tcpc, true); > - if (ret < 0) > - goto out_disable_mux; > + if (port->pd_supported) { > + ret = port->tcpc->set_pd_rx(port->tcpc, true); > + if (ret < 0) > + goto out_disable_mux; > + } > > /* > * USB Type-C specification, version 1.2, > @@ -3600,7 +3608,8 @@ static int tcpm_src_attach(struct tcpm_port *port) > out_disable_vconn: > tcpm_set_vconn(port, false); > out_disable_pd: > - port->tcpc->set_pd_rx(port->tcpc, false); > + if (port->pd_supported) > + port->tcpc->set_pd_rx(port->tcpc, false); > out_disable_mux: > tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE, > TYPEC_ORIENTATION_NONE); > @@ -3804,6 +3813,20 @@ static enum typec_pwr_opmode tcpm_get_pwr_opmode(enum typec_cc_status cc) > } > } > > +static enum typec_cc_status tcpm_pwr_opmode_to_rp(enum typec_pwr_opmode opmode) > +{ > + switch (opmode) { > + case TYPEC_PWR_MODE_USB: > + return TYPEC_CC_RP_DEF; > + case TYPEC_PWR_MODE_1_5A: > + return TYPEC_CC_RP_1_5; > + case TYPEC_PWR_MODE_3_0A: > + case TYPEC_PWR_MODE_PD: > + default: > + return TYPEC_CC_RP_3_0; > + } > +} > + > static void run_state_machine(struct tcpm_port *port) > { > int ret; > @@ -3914,6 +3937,10 @@ static void run_state_machine(struct tcpm_port *port) > if (port->ams == POWER_ROLE_SWAP || > port->ams == FAST_ROLE_SWAP) > tcpm_ams_finish(port); > + if (!port->pd_supported) { > + tcpm_set_state(port, SRC_READY, 0); > + break; > + } > port->upcoming_state = SRC_SEND_CAPABILITIES; > tcpm_ams_start(port, POWER_NEGOTIATION); > break; > @@ -4161,7 +4188,10 @@ static void run_state_machine(struct tcpm_port *port) > current_lim = PD_P_SNK_STDBY_MW / 5; > tcpm_set_current_limit(port, current_lim, 5000); > tcpm_set_charge(port, true); > - tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0); > + if (!port->pd_supported) > + tcpm_set_state(port, SNK_READY, 0); > + else > + tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0); > break; > } > /* > @@ -4389,7 +4419,8 @@ static void run_state_machine(struct tcpm_port *port) > tcpm_set_vbus(port, true); > if (port->ams == HARD_RESET) > tcpm_ams_finish(port); > - port->tcpc->set_pd_rx(port->tcpc, true); > + if (port->pd_supported) > + port->tcpc->set_pd_rx(port->tcpc, true); > tcpm_set_attached_state(port, true); > tcpm_set_state(port, SRC_UNATTACHED, PD_T_PS_SOURCE_ON); > break; > @@ -5898,6 +5929,7 @@ EXPORT_SYMBOL_GPL(tcpm_tcpc_reset); > static int tcpm_fw_get_caps(struct tcpm_port *port, > struct fwnode_handle *fwnode) > { > + const char *opmode_str; > const char *cap_str; > int ret; > u32 mw, frs_current; > @@ -5932,22 +5964,36 @@ static int tcpm_fw_get_caps(struct tcpm_port *port, > return ret; > port->typec_caps.type = ret; > port->port_type = port->typec_caps.type; > + port->pd_supported = fwnode_property_read_bool(fwnode, "pd-supported"); >
As mentioned in the other patch, I think this needs to be negated. Not the variable itself, but the meaning of the property.
> port->slow_charger_loop = fwnode_property_read_bool(fwnode, "slow-charger-loop");
It might make sense to move the properties needed with !pd_supported to here and return immediately after they are read. This would reduce the number of required changes and avoid trying to read irrelevant properties. Something like
if (port->port_type != TYPEC_PORT_SRC) port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
if (!port->pd_supported) return 0;
> if (port->port_type == TYPEC_PORT_SNK) > goto sink; > > /* Get source pdos */ > - ret = fwnode_property_count_u32(fwnode, "source-pdos"); > - if (ret <= 0) > - return -EINVAL; > + if (port->pd_supported) { > + ret = fwnode_property_count_u32(fwnode, "source-pdos"); > + if (ret <= 0) > + return -EINVAL; > > - port->nr_src_pdo = min(ret, PDO_MAX_OBJECTS); > - ret = fwnode_property_read_u32_array(fwnode, "source-pdos", > - port->src_pdo, port->nr_src_pdo); > - if ((ret < 0) || tcpm_validate_caps(port, port->src_pdo, > - port->nr_src_pdo)) > - return -EINVAL; > + port->nr_src_pdo = min(ret, PDO_MAX_OBJECTS); > + ret = fwnode_property_read_u32_array(fwnode, "source-pdos", > + port->src_pdo, port->nr_src_pdo); > + if ((ret < 0) || tcpm_validate_caps(port, port->src_pdo, > + port->nr_src_pdo)) > + return -EINVAL; > + } else { > + port->nr_src_pdo = 0; > + ret = fwnode_property_read_string(fwnode, "typec-power-opmode", &opmode_str); > + if (ret == 0) { > + ret = typec_find_pwr_opmode(opmode_str); > + if (ret < 0) > + return ret; > + port->src_rp = tcpm_pwr_opmode_to_rp(ret); > + } else { > + return ret; > + } > + } > > if (port->port_type == TYPEC_PORT_SRC) > return 0; > @@ -5962,25 +6008,29 @@ static int tcpm_fw_get_caps(struct tcpm_port *port, > return -EINVAL; > sink: > /* Get sink pdos */ > - ret = fwnode_property_count_u32(fwnode, "sink-pdos"); > - if (ret <= 0) > - return -EINVAL; > + if (port->pd_supported) { > + ret = fwnode_property_count_u32(fwnode, "sink-pdos"); > + if (ret <= 0) > + return -EINVAL; > > - port->nr_snk_pdo = min(ret, PDO_MAX_OBJECTS); > - ret = fwnode_property_read_u32_array(fwnode, "sink-pdos", > - port->snk_pdo, port->nr_snk_pdo); > - if ((ret < 0) || tcpm_validate_caps(port, port->snk_pdo, > - port->nr_snk_pdo)) > - return -EINVAL; > + port->nr_snk_pdo = min(ret, PDO_MAX_OBJECTS); > + ret = fwnode_property_read_u32_array(fwnode, "sink-pdos", > + port->snk_pdo, port->nr_snk_pdo); > + if ((ret < 0) || tcpm_validate_caps(port, port->snk_pdo, > + port->nr_snk_pdo)) > + return -EINVAL; > > - if (fwnode_property_read_u32(fwnode, "op-sink-microwatt", &mw) < 0) > - return -EINVAL; > - port->operating_snk_mw = mw / 1000; > + if (fwnode_property_read_u32(fwnode, "op-sink-microwatt", &mw) < 0) > + return -EINVAL; > + port->operating_snk_mw = mw / 1000; > + } else { > + port->nr_snk_pdo = 0; > + } > > port->self_powered = fwnode_property_read_bool(fwnode, "self-powered"); > > - /* FRS can only be supported byb DRP ports */ > - if (port->port_type == TYPEC_PORT_DRP) { > + /* FRS can only be supported by DRP ports */ > + if (port->port_type == TYPEC_PORT_DRP && port->pd_supported) { > ret = fwnode_property_read_u32(fwnode, "new-source-frs-typec-current", > &frs_current); > if (ret >= 0 && frs_current <= FRS_5V_3A) >
| |