Re: [PATCH] usb: gadget: udc_core: Use right kobj when calling sysfs_notify

[Andreas Larsson]

On 2014-09-16 07:15, Felipe Balbi wrote:
> Hi,
>
> On Tue, Sep 16, 2014 at 10:02:25AM +0800, Peter Chen wrote:
> > On Mon, Sep 15, 2014 at 12:42:27PM +0200, Andreas Larsson wrote:
> > > The state attribute is connected to the kobj of the udc, not the gadget.
> > >
> > > Signed-off-by: Andreas Larsson <andreas@xxxxxxxxxxx>
> > > ---
> > >   drivers/usb/gadget/udc/udc-core.c |   14 +++++++++++++-
> > >   1 file changed, 13 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c
> > > index b0d9817..37c129a 100644
> > > --- a/drivers/usb/gadget/udc/udc-core.c
> > > +++ b/drivers/usb/gadget/udc/udc-core.c
> > > @@ -109,8 +109,20 @@ EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
> > >   static void usb_gadget_state_work(struct work_struct *work)
> > >   {
> > >   	struct usb_gadget	*gadget = work_to_gadget(work);
> > > +	struct usb_udc		*udc = NULL;
> > > +
> > > +	mutex_lock(&udc_lock);
> > > +	list_for_each_entry(udc, &udc_list, list)
> > > +		if (udc->gadget == gadget)
> > > +			goto found;
> > > +	mutex_unlock(&udc_lock);
> > > +
> > > +	return;
> > > +
> > > +found:
> > > +	mutex_unlock(&udc_lock);
> > >
> > > -	sysfs_notify(&gadget->dev.kobj, NULL, "state");
> > > +	sysfs_notify(&udc->dev.kobj, NULL, "state");
> > >   }
> > >
> > >   void usb_gadget_set_state(struct usb_gadget *gadget,
> >
> > What's the user mode difference with and without this patch?
>
> poll() will actually wakeup ?

Yes, that is indeed the difference.

Cheers,
Andreas Larsson
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