usb: dwc3: Prevent indefinite sleep in _dwc3_set_mode during suspend/resume

In the following test we get stuck by sleeping forever in _dwc3_set_mode()
after which dual-role switching doesn't work.

On dra7-evm's dual-role port,
- Load g_zero gadget driver and enumerate to host
- suspend to mem
- disconnect USB cable to host and connect otg cable with Pen drive in it.
- resume system
- we sleep indefinitely in _dwc3_set_mode due to.
  dwc3_gadget_exit()->usb_del_gadget_udc()->udc_stop()->
	dwc3_gadget_stop()->wait_event_lock_irq()

To fix this instead of waiting indefinitely with wait_event_lock_irq()
we use wait_event_interruptible_lock_irq_timeout() and print
and error message if there was a timeout.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
This commit is contained in:
Roger Quadros 2018-03-09 14:47:04 +02:00 committed by Felipe Balbi
parent 365b7673c3
commit 498f0478ab

View File

@ -1950,6 +1950,7 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
int epnum;
u32 tmo_eps = 0;
spin_lock_irqsave(&dwc->lock, flags);
@ -1960,6 +1961,7 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
struct dwc3_ep *dep = dwc->eps[epnum];
int ret;
if (!dep)
continue;
@ -1967,9 +1969,24 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
continue;
wait_event_lock_irq(dep->wait_end_transfer,
!(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
dwc->lock);
ret = wait_event_interruptible_lock_irq_timeout(dep->wait_end_transfer,
!(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
dwc->lock, msecs_to_jiffies(5));
if (ret <= 0) {
/* Timed out or interrupted! There's nothing much
* we can do so we just log here and print which
* endpoints timed out at the end.
*/
tmo_eps |= 1 << epnum;
dep->flags &= DWC3_EP_END_TRANSFER_PENDING;
}
}
if (tmo_eps) {
dev_err(dwc->dev,
"end transfer timed out on endpoints 0x%x [bitmap]\n",
tmo_eps);
}
out: