Hi,
On Fri, Mar 08, 2013 at 08:37:00PM +0800, Peter Chen wrote:
> On Fri, Mar 08, 2013 at 01:30:52PM +0200, Felipe Balbi wrote:
> > this method will be used to enable or disable
> > the charge pump.
> >
> > Whenever we have DRD devices, we need to be
> > able to turn VBUS on or off whenever we want.
> >
> > Note that in the ideal case, this would be
> > controlled by the ID-pin Interrupt, but not
> > all devices have ID-pin properly routed since
> > manufacturers can choose to save that trace
> > if they're building a host-only product out
> > of a DRD IP.
> >
> > This is also useful during debugging where
> > we might not have the proper cable hanging
> > around.
> >
> > Signed-off-by: Felipe Balbi <balbi@xxxxxx>
> > ---
> > include/linux/usb/phy.h | 21 +++++++++++++++++++++
> > 1 file changed, 21 insertions(+)
> >
> > diff --git a/include/linux/usb/phy.h b/include/linux/usb/phy.h
> > index b001dc3..b7c2217 100644
> > --- a/include/linux/usb/phy.h
> > +++ b/include/linux/usb/phy.h
> > @@ -91,6 +91,9 @@ struct usb_phy {
> > int (*init)(struct usb_phy *x);
> > void (*shutdown)(struct usb_phy *x);
> >
> > + /* enable/disable VBUS */
> > + int (*set_vbus)(struct usb_phy *x, int on);
> > +
> > /* effective for B devices, ignored for A-peripheral */
> > int (*set_power)(struct usb_phy *x,
> > unsigned mA);
> > @@ -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.
yeah, that's gotta go. Even if we're host only, we might still want to
disable the charge pump to save some power.
If you look into USB Power Delivery class, some new connectors will be
coming to the market where there will be a switch inside the connector
so you can know a cable is connected. That means we can keep vbus turned
off until that switch is toggled, clearly not an OTG-specific thing ;-)
Thanks for spotting that, do you wanna send a patch removing set_vbus
from otg.h ? There are some users of that though:
$ git grep -e otg_set_vbus
arch/arm/mach-pxa/pxa3xx-ulpi.c: err = otg_set_vbus(u2d->otg->otg, 1);
arch/arm/mach-pxa/pxa3xx-ulpi.c: otg_set_vbus(u2d->otg->otg, 0);
drivers/usb/host/ehci-mxc.c: ret = otg_set_vbus(pdata->otg->otg, 1);
drivers/usb/musb/musb_gadget.c: otg_set_vbus(otg, 1);
drivers/usb/musb/omap2430.c: otg_set_vbus(otg, 1);
drivers/usb/musb/omap2430.c: otg_set_vbus(musb->xceiv->otg, 0);
I guess most are easy enough to fix by switching over to the phy
interface. Doesn't to happen *right now* though.
cheers
--
balbi
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