usb: dwc3: clear 'res_trans_idx' as soon as it becomes invalid

Transfer resource index is cleared in hardware when XFERCOMPLETE
event is generated, so clear the driver's res_trans_idx variable
immediately after that event is received. The upcoming hibernation
patches depend on this change.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

2 files changed, 4 insertions, 3 deletions

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 4fa2c9873ea..73efdf6938a 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -617,6 +617,7 @@ static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
         struct dwc3_ep          *dep = dwc->eps[event->endpoint_number];
 
         dep->flags &= ~DWC3_EP_BUSY;
+        dep->res_trans_idx = 0;
         dwc->setup_packet_pending = false;
 
         switch (dwc->ep0state) {
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index bfdfd4f151f..da317f6a8bc 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1628,10 +1628,8 @@ static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
                 status = -ECONNRESET;
 
         clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
-        if (clean_busy) {
+        if (clean_busy)
                 dep->flags &= ~DWC3_EP_BUSY;
-                dep->res_trans_idx = 0;
-        }
 
         /*
          * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
@@ -1736,6 +1734,8 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
 
         switch (event->endpoint_event) {
         case DWC3_DEPEVT_XFERCOMPLETE:
+                dep->res_trans_idx = 0;
+
                 if (usb_endpoint_xfer_isoc(dep->desc)) {
                         dev_dbg(dwc->dev, "%s is an Isochronous endpoint\n",
                                         dep->name);