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

commit 308c316d16cbad99bb834767382baa693ac42169 upstream.

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 4f59a2afc91bcd81571aec51c65258309e5b55bc..2565a8f129234c9ecf1a91f62d80a1a5a0051f27 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1277,8 +1277,8 @@ 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: