Commit 359d5a85 authored by Wesley Cheng's avatar Wesley Cheng Committed by Greg Kroah-Hartman
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usb: dwc3: Do not service EP0 and conndone events if soft disconnected 



There are some operations that need to be ignored if there is a soft
disconnect in progress.  This is to avoid having a pending EP0 transfer in
progress while attempting to stop active transfers and halting the
controller.

There were several instances seen where a soft disconnect was able to occur
during early link negotiation, i.e. bus reset/conndone, which leads to the
conndone handler re-configuring EPs while attempting to halt the
controller, as DEP flags are cleared as part of the soft disconnect path.

ep0out: cmd 'Start New Configuration'
ep0out: cmd 'Set Endpoint Transfer Resource'
ep0in: cmd 'Set Endpoint Transfer Resource'
ep1out: cmd 'Set Endpoint Transfer Resource'
...
event (00030601): Suspend [U3]
event (00000101): Reset [U0]
ep0out: req ffffff87e5c9e100 length 0/0 zsI ==> 0
event (00000201): Connection Done [U0]
ep0out: cmd 'Start New Configuration'
ep0out: cmd 'Set Endpoint Transfer Resource'

In addition, if a soft disconnect occurs, EP0 events are still allowed to
process, however, it will stall/restart during the SETUP phase.  The
host is still able to query for the DATA phase, leading to a
xfernotready(DATA) event.  Since none of the SETUP transfer parameters are
populated, the xfernotready is treated as a "wrong direction" error,
leading to a duplicate stall/restart routine.

Add the proper softconnect/connected checks in sequences that are
potentially involved during soft disconnect processing.

Reviewed-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: default avatarWesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/20220817182359.13550-2-quic_wcheng@quicinc.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c69400b0

drivers/usb/dwc3/ep0.c

+4 −2
Original line number Diff line number Diff line
@@ -197,7 +197,7 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request, 
	int				ret;



	spin_lock_irqsave(&dwc->lock, flags);

	if (!dep->endpoint.desc || !dwc->pullups_connected) {

	if (!dep->endpoint.desc || !dwc->pullups_connected || !dwc->connected) {

		dev_err(dwc->dev, "%s: can't queue to disabled endpoint\n",

				dep->name);

		ret = -ESHUTDOWN;
@@ -815,7 +815,7 @@ static void dwc3_ep0_inspect_setup(struct dwc3 *dwc, 
	int ret = -EINVAL;

	u32 len;



	if (!dwc->gadget_driver || !dwc->connected)

	if (!dwc->gadget_driver || !dwc->softconnect || !dwc->connected)

		goto out;



	trace_dwc3_ctrl_req(ctrl);
@@ -1118,6 +1118,8 @@ static void dwc3_ep0_xfernotready(struct dwc3 *dwc, 
{

	switch (event->status) {

	case DEPEVT_STATUS_CONTROL_DATA:

		if (!dwc->softconnect || !dwc->connected)

			return;

		/*

		 * We already have a DATA transfer in the controller's cache,

		 * if we receive a XferNotReady(DATA) we will ignore it, unless

drivers/usb/dwc3/gadget.c

+3 −0
Original line number Diff line number Diff line
@@ -3865,6 +3865,9 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc) 
	u8			lanes = 1;

	u8			speed;



	if (!dwc->softconnect)

		return;



	reg = dwc3_readl(dwc->regs, DWC3_DSTS);

	speed = reg & DWC3_DSTS_CONNECTSPD;

	dwc->speed = speed;