On Wed, Jun 22, 2016 at 12:50:16PM +0300, Heikki Krogerus wrote: > On Tue, Jun 21, 2016 at 10:25:05PM +0200, Oliver Neukum wrote: > > On Tue, 2016-06-21 at 17:51 +0300, Heikki Krogerus wrote: > > > +What: /sys/class/typec/<port>/supported_data_roles > > > +Data: June 2016 > > > +Contact: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > > > +Description: > > > + Lists the USB data roles, host or device, the port is > > > capable > > > + of supporting. > > > > On third thought, this is a problem. Looking at 4.4.8.1 > > DEVICE_CAPABILITIES (Required) of USB Type-C Port Controller > > Interface Specification we lack capability. > > > > A port that can do DRP is not the same thing as a port that > > can be switched between DFP and UFP. We cannot express that. > > What do you mean? DRP means we support and are able to swap the data > role, but it just does not mean we can act as both source and sink. And > that information we already get from separate attribute: > "supported_power_roles". > > But if the port is DRP, we will always be able to swap the data role > between DFP and UFP. Just to clarify: DRP as it's defined in Type-C spec < 1.2 means the data role, not power role. And that is what Universal Serial Bus Type-CTM Port Controller specification is based on. Please correct me if I'm wrong. Thanks, -- heikki -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
