Re: [PATCH v5 4/6] usb: roles: add API to get usb_role_switch by node

Heikki Krogerus
2019-05-27T10:45:14Z

Hi,

> > IMO that case should be handled in USB role switch API initially, not
> > in the device connection API. If there is another user for it one day,
> > then we can move it to device connection API, but not before that.
> Ok
> >
> > How about this on top of the two patches I sent:
> I just test it, it works well.
> I'll prepare a patch and put into this series.
>
> >
> > diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
> > index aab795b54c7f..36ac9d181e09 100644
> > --- a/drivers/usb/roles/class.c
> > +++ b/drivers/usb/roles/class.c
> > @@ -114,6 +114,19 @@ static void *usb_role_switch_match(struct device_connection *con, int ep,
> > return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER);
> > }
> >
> > +static struct usb_role_switch *
> > +usb_role_switch_is_parent(struct fwnode_handle *parent)
> > +{
> > + struct device *dev;
> > +
> > + if (!parent || !fwnode_property_present(parent, "usb-role-switch"))
> > + return NULL;
> > +
> > + dev = class_find_device(role_class, NULL, parent, switch_fwnode_match);
> > +
> > + return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER);
> > +}
> > +
> > /**
> > * usb_role_switch_get - Find USB role switch linked with the caller
> > * @dev: The caller device
> > @@ -125,6 +138,10 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev)
> > {
> > struct usb_role_switch *sw;
> >
> > + sw = usb_role_switch_is_parent(fwnode_get_parent(dev_fwnode(dev)));
> > + if (sw)
> > + return sw;
> Do we also need to get parent module before return?

Yes.

thanks,

--
heikki