[PATCH 5.9 121/133] usb: dwc3: ep0: Fix delay status handling

From: Greg Kroah-Hartman
Date: Mon Nov 09 2020 - 08:22:00 EST


From: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>

commit fa27e2f6c5e674f3f1225f9ca7a7821faaf393bb upstream.

If we want to send a control status on our own time (through
delayed_status), make sure to handle a case where we may queue the
delayed status before the host requesting for it (when XferNotReady
is generated). Otherwise, the driver won't send anything because it's
not EP0_STATUS_PHASE yet. To resolve this, regardless whether
dwc->ep0state is EP0_STATUS_PHASE, make sure to clear the
dwc->delayed_status flag if dwc3_ep0_send_delayed_status() is called.
The control status can be sent when the host requests it later.

Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: d97c78a1908e ("usb: dwc3: gadget: END_TRANSFER before CLEAR_STALL command")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/dwc3/ep0.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -1058,10 +1058,11 @@ void dwc3_ep0_send_delayed_status(struct
{
unsigned int direction = !dwc->ep0_expect_in;

+ dwc->delayed_status = false;
+
if (dwc->ep0state != EP0_STATUS_PHASE)
return;

- dwc->delayed_status = false;
__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
}