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path: root/drivers/usb/dwc2/hcd_intr.c
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Diffstat (limited to 'drivers/usb/dwc2/hcd_intr.c')
-rw-r--r--drivers/usb/dwc2/hcd_intr.c9
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
index ed7f05cf4906..8ce10caf3e19 100644
--- a/drivers/usb/dwc2/hcd_intr.c
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -1231,7 +1231,10 @@ static void dwc2_hc_nak_intr(struct dwc2_hsotg *hsotg,
* avoid interrupt storms we'll wait before retrying if we've got
* several NAKs. If we didn't do this we'd retry directly from the
* interrupt handler and could end up quickly getting another
- * interrupt (another NAK), which we'd retry.
+ * interrupt (another NAK), which we'd retry. Note that we do not
+ * delay retries for IN parts of control requests, as those are expected
+ * to complete fairly quickly, and if we delay them we risk confusing
+ * the device and cause it issue STALL.
*
* Note that in DMA mode software only gets involved to re-send NAKed
* transfers for split transactions, so we only need to apply this
@@ -1244,7 +1247,9 @@ static void dwc2_hc_nak_intr(struct dwc2_hsotg *hsotg,
qtd->error_count = 0;
qtd->complete_split = 0;
qtd->num_naks++;
- qtd->qh->want_wait = qtd->num_naks >= DWC2_NAKS_BEFORE_DELAY;
+ qtd->qh->want_wait = qtd->num_naks >= DWC2_NAKS_BEFORE_DELAY &&
+ !(chan->ep_type == USB_ENDPOINT_XFER_CONTROL &&
+ chan->ep_is_in);
dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NAK);
goto handle_nak_done;
}