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SubjectRE: [PATCH 1/2] usb: dwc2: add ep enabled flag to avoid double enable/disable
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Hi, Balbi,
Please ignore this patch set. Because we have a fix in gadget API layer.
[PATCH] usb: gadget: forbid queuing request to a disabled ep

> > Enabling an already enabled ep is illegal, because the ep may has trbs
> > running. Reprogram the ep may break running transfer. So udc driver
> > must avoid this happening by return an error -EBUSY. Gadget function
> > driver also should avoid such things, but that is out of udc driver.
> >
> > Similarly, disable a disabled ep makes no sense, but no need return
> > an error here.
> >
> > Signed-off-by: Du, Changbin <changbin.du@intel.com>
> > ---
> > drivers/usb/dwc2/core.h | 1 +
> > drivers/usb/dwc2/gadget.c | 20 +++++++++++++++++++-
> > 2 files changed, 20 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> > index a66d3cb..cf7eccd 100644
> > --- a/drivers/usb/dwc2/core.h
> > +++ b/drivers/usb/dwc2/core.h
> > @@ -162,6 +162,7 @@ struct dwc2_hsotg_ep {
> > unsigned char mc;
> > unsigned char interval;
> >
> > + unsigned int enabled:1;
> > unsigned int halted:1;
> > unsigned int periodic:1;
> > unsigned int isochronous:1;
> > diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> > index 0abf73c..586bbcd 100644
> > --- a/drivers/usb/dwc2/gadget.c
> > +++ b/drivers/usb/dwc2/gadget.c
> > @@ -2423,6 +2423,7 @@ void dwc2_hsotg_core_init_disconnected(struct
> dwc2_hsotg *hsotg,
> > /* enable, but don't activate EP0in */
> > dwc2_writel(dwc2_hsotg_ep0_mps(hsotg->eps_out[0]-
> >ep.maxpacket) |
> > DXEPCTL_USBACTEP, hsotg->regs + DIEPCTL0);
> > + hsotg->eps_out[0]->enabled = 1;
> >
> > dwc2_hsotg_enqueue_setup(hsotg);
> >
> > @@ -2680,6 +2681,14 @@ static int dwc2_hsotg_ep_enable(struct usb_ep
> *ep,
> > return -EINVAL;
> > }
> >
> > + spin_lock_irqsave(&hsotg->lock, flags);
> > + if (hs_ep->enabled) {
> > + dev_warn(hsotg->dev, "%s: ep %s already enabled\n",
> > + __func__, hs_ep->name);
>
> this is a rather serious condition. I'd rather use dev_WARN_ONCE():
>
> if (dev_WARN_ONCE(hsotg->dev, hs_ep->enabled,
> "ep %s already enabled\n", hs_ep->name)) {
>
> --
> balbi


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