On Mon, Feb 1, 2021 at 6:59 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> On 2/1/21 1:53 AM, Badhri Jagan Sridharan wrote:
> > The USB Communications Capable bit indicates if port
> > partner is capable of communication over the USB data lines
> > (e.g. D+/- or SS Tx/Rx). Notify the status of the bit to low
> > level drivers to perform chip specific operation.
> > For instance, low level driver enables USB switches on D+/D-
> > lines to set up data path when the bit is set.
> >
> > Refactored from patch initially authored by
> > Kyle Tso <kyletso@xxxxxxxxxx>
> >
> > Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
> > ---
> > drivers/usb/typec/tcpm/tcpm.c | 16 ++++++++++++++++
> > include/linux/usb/tcpm.h | 5 +++++
> > 2 files changed, 21 insertions(+)
> >
> > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> > index 0afd8ef692e8..96190b4d46a7 100644
> > --- a/drivers/usb/typec/tcpm/tcpm.c
> > +++ b/drivers/usb/typec/tcpm/tcpm.c
> > @@ -298,6 +298,7 @@ struct tcpm_port {
> > struct usb_pd_identity partner_ident;
> > struct typec_partner_desc partner_desc;
> > struct typec_partner *partner;
> > + bool partner_usb_comm_capable;
> >
> > enum typec_cc_status cc_req;
> >
> > @@ -3429,6 +3430,16 @@ static void tcpm_unregister_altmodes(struct tcpm_port *port)
> > memset(modep, 0, sizeof(*modep));
> > }
> >
> > +static void tcpm_set_partner_usb_comm_capable(struct tcpm_port *port, bool capable)
> > +{
> > + tcpm_log(port, "Setting usb_comm capable %s", capable ? "true" : "false");
> > +
> > + if (port->tcpc->set_partner_usb_comm_capable)
> > + port->tcpc->set_partner_usb_comm_capable(port->tcpc, capable);
> > +
> > + port->partner_usb_comm_capable = capable;
> > +}
> > +
> > static void tcpm_reset_port(struct tcpm_port *port)
> > {
> > int ret;
> > @@ -3445,6 +3456,7 @@ static void tcpm_reset_port(struct tcpm_port *port)
> > port->attached = false;
> > port->pd_capable = false;
> > port->pps_data.supported = false;
> > + tcpm_set_partner_usb_comm_capable(port, false);
> >
> > /*
> > * First Rx ID should be 0; set this to a sentinel of -1 so that
> > @@ -3785,6 +3797,8 @@ static void run_state_machine(struct tcpm_port *port)
> > }
> > } else {
> > tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
> > + port->partner_usb_comm_capable = port->sink_request & RDO_USB_COMM;
>
> That seems to be redundant since tcpm_set_partner_usb_comm_capable() is setting it again.
You are correct. This is redundant. Removing in V2 version.
>
> > + tcpm_set_partner_usb_comm_capable(port, port->partner_usb_comm_capable);
> > tcpm_set_state(port, SRC_TRANSITION_SUPPLY,
> > PD_T_SRC_TRANSITION);
> > }
> > @@ -4004,6 +4018,8 @@ static void run_state_machine(struct tcpm_port *port)
> > break;
> > case SNK_NEGOTIATE_CAPABILITIES:
> > port->pd_capable = true;
> > + port->partner_usb_comm_capable = port->sink_request & RDO_USB_COMM;
>
> Same here. But then I don't really see where this variable is actually used.
> Am I missing something ?
Not used anywhere else. Removing this in V2.
Also fixing the check for this case. It should have been
port->source_caps[0] & PDO_FIXED_USB_COMM
Thanks for the reviews,
Badhri
>
> Thanks,
> Guenter
>
> > + tcpm_set_partner_usb_comm_capable(port, port->partner_usb_comm_capable);
> > port->hard_reset_count = 0;
> > ret = tcpm_pd_send_request(port);
> > if (ret < 0) {
> > diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
> > index 3af99f85e8b9..42fcfbe10590 100644
> > --- a/include/linux/usb/tcpm.h
> > +++ b/include/linux/usb/tcpm.h
> > @@ -108,6 +108,10 @@ enum tcpm_transmit_type {
> > * is supported by TCPC, set this callback for TCPM to query
> > * whether vbus is at VSAFE0V when needed.
> > * Returns true when vbus is at VSAFE0V, false otherwise.
> > + * @set_partner_usb_comm_capable:
> > + * Optional; The USB Communications Capable bit indicates if port
> > + * partner is capable of communication over the USB data lines
> > + * (e.g. D+/- or SS Tx/Rx). Called to notify the status of the bit.
> > */
> > struct tcpc_dev {
> > struct fwnode_handle *fwnode;
> > @@ -139,6 +143,7 @@ struct tcpc_dev {
> > int (*set_auto_vbus_discharge_threshold)(struct tcpc_dev *dev, enum typec_pwr_opmode mode,
> > bool pps_active, u32 requested_vbus_voltage);
> > bool (*is_vbus_vsafe0v)(struct tcpc_dev *dev);
> > + void (*set_partner_usb_comm_capable)(struct tcpc_dev *dev, bool enable);
> > };
> >
> > struct tcpm_port;
> >
>
