Commit e1dadd3b authored by Felipe Balbi's avatar Felipe Balbi
Browse files

usb: dwc3: workaround: bogus hibernation events 



Revision 2.20a of the core has a known issue
which would generate bogus hibernation events
_and_ random failures on USB CV TD.9.23 test
case.

The suggested workaround is to ignore hibernation
events which don't match currently connected
speed.

Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 32a4a135

drivers/usb/dwc3/gadget.c

+31 −0
Original line number Diff line number Diff line
@@ -2378,6 +2378,30 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc, 
	dev_vdbg(dwc->dev, "%s link %d\n", __func__, dwc->link_state);

}



static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,

		unsigned int evtinfo)

{

	unsigned int is_ss = evtinfo & BIT(4);



	/**

	 * WORKAROUND: DWC3 revison 2.20a with hibernation support

	 * have a known issue which can cause USB CV TD.9.23 to fail

	 * randomly.

	 *

	 * Because of this issue, core could generate bogus hibernation

	 * events which SW needs to ignore.

	 *

	 * Refers to:

	 *

	 * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0

	 * Device Fallback from SuperSpeed

	 */

	if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))

		return;



	/* enter hibernation here */

}



static void dwc3_gadget_interrupt(struct dwc3 *dwc,

		const struct dwc3_event_devt *event)

{
@@ -2394,6 +2418,13 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc, 
	case DWC3_DEVICE_EVENT_WAKEUP:

		dwc3_gadget_wakeup_interrupt(dwc);

		break;

	case DWC3_DEVICE_EVENT_HIBER_REQ:

		if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,

					"unexpected hibernation event\n"))

			break;



		dwc3_gadget_hibernation_interrupt(dwc, event->event_info);

		break;

	case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:

		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);

		break;