On Tue, May 15, 2018 at 08:02:00AM +0000, Yoshihiro Shimoda wrote:
> Hi Simon-san,
>
> Thank you for your review!
>
> > From: Simon Horman, Sent: Tuesday, May 15, 2018 4:54 PM
> > On Mon, May 14, 2018 at 06:15:59PM +0900, Yoshihiro Shimoda wrote:
> <snip>
> > > static void usb3_set_mode(struct renesas_usb3 *usb3, bool host)
> > > {
> > > - _usb3_set_mode(usb3, host);
> > > + if (usb3->role_sw)
> > > + usb_role_switch_set_role(usb3->role_sw, host ?
> > > + USB_ROLE_HOST : USB_ROLE_DEVICE);
> > > + else
> > > + _usb3_set_mode(usb3, host);
> > > }
> > >
> > > static void usb3_vbus_out(struct renesas_usb3 *usb3, bool enable)
> > > @@ -672,8 +676,8 @@ static void usb3_mode_config(struct renesas_usb3 *usb3, bool host, bool a_dev)
> > > {
> > > unsigned long flags;
> > >
> > > - spin_lock_irqsave(&usb3->lock, flags);
> > > usb3_set_mode(usb3, host);
> > > + spin_lock_irqsave(&usb3->lock, flags);
> >
> > Hi Shimoda-san,
> >
> > could you clarify why moving this lock is safe?
>
> The usb3_set_mode() is possible to call usb_role_switch_set_role() API
> and usb_role_switch_set_role() calls mutex_lock().
> So, this moving this lock (especially avoiding irqsave) needs.
Thanks, that make sense.
But usb3_set_mode() may also call _usb3_set_mode().
It is safe to call _usb3_set_mode() without holding the lock?
> Best regards,
> Yoshihiro Shimoda
>
> > > usb3_vbus_out(usb3, a_dev);
> > > /* for A-Peripheral or forced B-device mode */
> > > if ((!host && a_dev) ||
> > > --
> > > 1.9.1
> > >
>
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