Re: [RFC PATCHv3] usb: USB Type-C Connector Class

From: Heikki Krogerus
Date: Mon Jun 13 2016 - 03:49:10 EST


On Sat, Jun 11, 2016 at 09:05:46AM +0200, Oliver Neukum wrote:
> On Fri, 2016-06-10 at 17:34 +0300, Heikki Krogerus wrote:
> > +static ssize_t
> > +preferred_role_store(struct device *dev, struct device_attribute
> > *attr,
> > + const char *buf, size_t size)
> > +{
> > + struct typec_port *port = to_typec_port(dev);
> > + enum typec_role role;
> > + int ret;
> > +
> > + mutex_lock(&port->lock);
> > +
> > + if (port->cap->type != TYPEC_PORT_DRP) {
> > + dev_dbg(dev, "Try.SRC/SNK only supported with DRP
> > ports\n");
> > + ret = -EOPNOTSUPP;
> > + goto out;
> > + }
>
> I think Try.SNK with an UFP should fail differently from
> Try.SRC and vice versa.
>
> And, even more importantly, this offeres no way to cancel
> a preference.

Well, no way that would actually work. I'll fix that.

Thanks,

--
heikki