usb: dwc3: gadget: Don't set IMI for no_interrupt

The gadget driver may have a certain expectation of how the request
completion flow should be from to its configuration. Make sure the
controller driver respect that. That is, don't set IMI (Interrupt on
Missed Isoc) when usb_request->no_interrupt is set. Also, the driver
should only set IMI to the last TRB of a chain.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Cc: stable@vger.kernel.org
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Reviewed-by: Jeff Vanhoof <jdv1029@gmail.com>
Tested-by: Jeff Vanhoof <jdv1029@gmail.com>
Link: https://lore.kernel.org/r/ced336c84434571340c07994e3667a0ee284fefe.1666735451.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 230b3c66005401b72504f87444307d6670860483..5fe2d136dff51e32e59fe2b75bef0d6f1ad45bd4 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1292,8 +1292,8 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
                        trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
                }
 
-               /* always enable Interrupt on Missed ISOC */
-               trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
+               if (!no_interrupt && !chain)
+                       trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
                break;
 
        case USB_ENDPOINT_XFER_BULK: