On Thu, Jan 28, 2021 at 10:14:02PM -0800, Benson Leung wrote: > The USB Power Delivery specification Section 6.2.1.1.5 outlines > revision backward compatibility requirements starting from Revision 3.0. > > The Port, the Cable Plug, and the Port Partner may support either > revision 2 or revision 3 independently, and communication between ports, > partners, and cables of different revisions are allowed under rules > that the parties agree to communicate between each other using the > lowest common operating revision. > > This may mean that Port-to-Partner operating revision comms may be > different than Port-to-CablePlug operating revision comms. For example, > it is possible for a R3.0 port to communicate with a R3.0 partner > using R3.0 messages, while the R3.0 port (in the same session) must > communicate with the R2.0 cable using R2.0 messages only. > > Introduce individual revision number properties for cable > and port partner so that the port can track them independently. > > Signed-off-by: Benson Leung <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]> > --- > Documentation/ABI/testing/sysfs-class-typec | 13 +++++++++ > drivers/usb/typec/class.c | 30 ++++++++++++++++++--- > include/linux/usb/typec.h | 10 +++++++ > 3 files changed, 49 insertions(+), 4 deletions(-) > > diff --git a/Documentation/ABI/testing/sysfs-class-typec > b/Documentation/ABI/testing/sysfs-class-typec > index b61480535fdc..40122d915ae1 100644 > --- a/Documentation/ABI/testing/sysfs-class-typec > +++ b/Documentation/ABI/testing/sysfs-class-typec > @@ -112,6 +112,19 @@ Description: > - "3.0": USB Power Delivery Release 3.0 > - "3.1": USB Power Delivery Release 3.1 > > +What: > /sys/class/typec/<port>-{partner|cable}/usb_power_delivery_revision > +Date: January 2021 > +Contact: Benson Leung <[email protected]> > +Description: > + Revision number of the supported USB Power Delivery > + specification of the port partner or cable, or 0.0 when USB > + Power Delivery is not supported. > + > + Example values: > + - "2.0": USB Power Delivery Release 2.0 > + - "3.0": USB Power Delivery Release 3.0 > + - "3.1": USB Power Delivery Release 3.1 > + > What: /sys/class/typec/<port>/usb_typec_revision > Date: April 2017 > Contact: Heikki Krogerus <[email protected]> > diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c > index 4f60ee7ba76a..b5241f4756c2 100644 > --- a/drivers/usb/typec/class.c > +++ b/drivers/usb/typec/class.c > @@ -27,6 +27,7 @@ struct typec_cable { > enum typec_plug_type type; > struct usb_pd_identity *identity; > unsigned int active:1; > + u16 pd_revision; /* 0300H = "3.0" */ > }; > > struct typec_partner { > @@ -36,6 +37,7 @@ struct typec_partner { > enum typec_accessory accessory; > struct ida mode_ids; > int num_altmodes; > + u16 pd_revision; /* 0300H = "3.0" */ > }; > > struct typec_port { > @@ -264,6 +266,11 @@ type_show(struct device *dev, struct device_attribute > *attr, char *buf) > } > static DEVICE_ATTR_RO(type); > > +static ssize_t usb_power_delivery_revision_show(struct device *dev, > + struct device_attribute *attr, > + char *buf); > +static DEVICE_ATTR_RO(usb_power_delivery_revision); > + > /* ------------------------------------------------------------------------- > */ > /* Alternate Modes */ > > @@ -680,6 +687,7 @@ static struct attribute *typec_partner_attrs[] = { > &dev_attr_supports_usb_power_delivery.attr, > &dev_attr_number_of_alternate_modes.attr, > &dev_attr_type.attr, > + &dev_attr_usb_power_delivery_revision.attr, > NULL > }; > > @@ -815,6 +823,7 @@ struct typec_partner *typec_register_partner(struct > typec_port *port, > partner->usb_pd = desc->usb_pd; > partner->accessory = desc->accessory; > partner->num_altmodes = -1; > + partner->pd_revision = desc->pd_revision; > > if (desc->identity) { > /* > @@ -1028,6 +1037,7 @@ static DEVICE_ATTR_RO(plug_type); > static struct attribute *typec_cable_attrs[] = { > &dev_attr_type.attr, > &dev_attr_plug_type.attr, > + &dev_attr_usb_power_delivery_revision.attr, > NULL > }; > ATTRIBUTE_GROUPS(typec_cable); > @@ -1130,6 +1140,7 @@ struct typec_cable *typec_register_cable(struct > typec_port *port, > > cable->type = desc->type; > cable->active = desc->active; > + cable->pd_revision = desc->pd_revision; > > if (desc->identity) { > /* > @@ -1499,12 +1510,23 @@ static ssize_t > usb_power_delivery_revision_show(struct device *dev, > struct device_attribute *attr, > char *buf) > { > - struct typec_port *p = to_typec_port(dev); > - u16 rev = p->cap->pd_revision; > + u16 rev = 0; > > - return sprintf(buf, "%d.%d\n", (rev >> 8) & 0xff, (rev >> 4) & 0xf); > + if (is_typec_partner(dev)) { > + struct typec_partner *partner = to_typec_partner(dev); > + > + rev = partner->pd_revision; > + } else if (is_typec_cable(dev)) { > + struct typec_cable *cable = to_typec_cable(dev); > + > + rev = cable->pd_revision; > + } else if (is_typec_port(dev)) { > + struct typec_port *p = to_typec_port(dev); > + > + rev = p->cap->pd_revision; > + } > + return sysfs_emit(buf, "%d.%d\n", (rev >> 8) & 0xff, (rev >> 4) & 0xf); > } > -static DEVICE_ATTR_RO(usb_power_delivery_revision); > > static ssize_t orientation_show(struct device *dev, > struct device_attribute *attr, > diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h > index 54475323f83b..42c6b7c07a99 100644 > --- a/include/linux/usb/typec.h > +++ b/include/linux/usb/typec.h > @@ -164,6 +164,7 @@ struct typec_plug_desc { > * @type: The plug type from USB PD Cable VDO > * @active: Is the cable active or passive > * @identity: Result of Discover Identity command > + * @pd_revision: USB Power Delivery Specification revision if supported > * > * Represents USB Type-C Cable attached to USB Type-C port. > */ > @@ -171,6 +172,8 @@ struct typec_cable_desc { > enum typec_plug_type type; > unsigned int active:1; > struct usb_pd_identity *identity; > + u16 pd_revision; /* 0300H = "3.0" */ > + > }; > > /* > @@ -178,15 +181,22 @@ struct typec_cable_desc { > * @usb_pd: USB Power Delivery support > * @accessory: Audio, Debug or none. > * @identity: Discover Identity command data > + * @pd_revision: USB Power Delivery Specification Revision if supported > * > * Details about a partner that is attached to USB Type-C port. If @identity > * member exists when partner is registered, a directory named "identity" is > * created to sysfs for the partner device. > + * > + * @pd_revision is based on the setting of the "Specification Revision" field > + * in the message header on the initial "Source Capabilities" message > received > + * from the partner, or a "Request" message received from the partner, > depending > + * on whether our port is a Sink or a Source. > */ > struct typec_partner_desc { > unsigned int usb_pd:1; > enum typec_accessory accessory; > struct usb_pd_identity *identity; > + u16 pd_revision; /* 0300H = "3.0" */ > }; > > /** > -- > 2.30.0.365.g02bc693789-goog thanks, -- heikki
