On Fri, Mar 15, 2013 at 09:53:27AM +0200, Felipe Balbi wrote:
> On Fri, Mar 15, 2013 at 02:15:16PM +0800, Peter Chen wrote:
> > On Thu, Mar 14, 2013 at 12:12:47PM +0200, Felipe Balbi wrote:
> > > Hi,
> > >
> > > On Thu, Mar 14, 2013 at 05:38:03PM +0800, Peter Chen wrote:
> > > > > > > @@ -160,6 +163,24 @@ usb_phy_shutdown(struct usb_phy *x)
> > > > > > > x->shutdown(x);
> > > > > > > }
> > > > > > >
> > > > > > > +static inline int
> > > > > > > +usb_phy_vbus_on(struct usb_phy *x)
> > > > > > > +{
> > > > > > > + if (!x->set_vbus)
> > > > > > > + return 0;
> > > > > > > +
> > > > > > > + return x->set_vbus(x, true);
> > > > > > > +}
> > > > > > > +
> > > > > > > +static inline int
> > > > > > > +usb_phy_vbus_off(struct usb_phy *x)
> > > > > > > +{
> > > > > > > + if (!x->set_vbus)
> > > > > > > + return 0;
> > > > > > > +
> > > > > > > + return x->set_vbus(x, false);
> > > > > > > +}
> > > > > > > +
> > > > > >
> > > > > > What's plan for otg's set_vbus? I suggest using phy's to instead of
> > > > > > otg's.
> > > > >
> > > >
> > > > When I think it more, does it work like below:
> > > >
> > > > - If PHY supplies vbus_setting function (like ulpi.c), the callback
> > > > is assigned at PHY driver.
> > > > - If board supplies vbus on/off function (through gpio), the callback
> > > > is assigned at controller driver.
> > > > Here vbus setting is USB staff, no limited to PHY.
> > >
> > > I wonder if the whole vbus toggling logic shouldn't, eventually, become
> > > a regulator. That would clean up a bunch of these details. I mean, we
> > > can still provide usb_phy_vbus_on()/off() but that would just call into
> > > the proper regulator.
> > >
> > > Also, I think we should have a single location where VBUS is controlled,
> > > since the VBUS line is directly routed to a pin in the PHY, the PHY
> >
> > Not for all, for chipidea phy, it has two regulators (2.5v and 3.3v)
> > from outside as phy's power.
> >
> > Even vbus pin is input for PHY, how can PHY turns on or off it without
> > external control like GPIO?
>
> that external control is a Fixed Regulator which your PHY driver
> requests and manages. Then you implement ->set_vbus() with:
>
> my_fancy_set_vbus()
> {
> if (on)
> ret = regulator_enable(reg);
> else
> ret = regulator_disable(reg);
>
> return ret;
> }
Yes, that is the solution.
My most concern is we design the API, how make the user
understand relationship between vbus and PHY, why .set_vbus
is put at PHY driver?
--
Best Regards,
Peter Chen
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