Re: [PATCH 4/6] usb: musb: mediatek: add reset FADDR to zero in reset interrupt handle

[Macpaul Lin <macpaul.lin@mediatek.com>]

On Wed, 2020-06-17 at 10:58 +0200, Greg Kroah-Hartman wrote:
> On Wed, Jun 17, 2020 at 04:17:07PM +0800, Macpaul Lin wrote:
> > Bin Liu <b-liu@ti.com> 於 2020年5月25日 週一 上午10:53寫道：
> > >
> > > From: Macpaul Lin <macpaul.lin@mediatek.com>
> > >
> > > When receiving reset interrupt, FADDR need to be reset to zero in
> > > peripheral mode. Otherwise ep0 cannot do enumeration when re-plugging USB
> > > cable.
> > >
> > > Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com>
> > > Acked-by: Min Guo <min.guo@mediatek.com>
> > > Signed-off-by: Bin Liu <b-liu@ti.com>
> > > ---
> > >  drivers/usb/musb/mediatek.c | 6 ++++++
> > >  1 file changed, 6 insertions(+)
> > >
> > > diff --git a/drivers/usb/musb/mediatek.c b/drivers/usb/musb/mediatek.c
> > > index 6196b0e8d77d..eebeadd26946 100644
> > > --- a/drivers/usb/musb/mediatek.c
> > > +++ b/drivers/usb/musb/mediatek.c
> > > @@ -208,6 +208,12 @@ static irqreturn_t generic_interrupt(int irq, void *__hci)
> > >         musb->int_rx = musb_clearw(musb->mregs, MUSB_INTRRX);
> > >         musb->int_tx = musb_clearw(musb->mregs, MUSB_INTRTX);
> > >
> > > +       if ((musb->int_usb & MUSB_INTR_RESET) && !is_host_active(musb)) {
> > > +               /* ep0 FADDR must be 0 when (re)entering peripheral mode */
> > > +               musb_ep_select(musb->mregs, 0);
> > > +               musb_writeb(musb->mregs, MUSB_FADDR, 0);
> > > +       }
> > > +
> > >         if (musb->int_usb || musb->int_tx || musb->int_rx)
> > >                 retval = musb_interrupt(musb);
> > >
> > > --
> > > 2.17.1
> > >
> > Could this bug fix also been applied to stable kernel?
> 
> Sure, what is the git commit of it in Linus's tree?
> 
> thanks,
> 
> greg k-h

The commit id of this patch should be
402bcac4b25b520c89ba60db85eb6316f36e797f

Thank you very much.

BR
Macpaul Lin