This is a note to let you know that I've just added the patch titled usb: dwc3: gadget: Fix ISO transfer performance to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-dwc3-gadget-fix-iso-transfer-performance.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f1d6826cae30e97e37a1f2481d7e1dc4faa09ce1 Mon Sep 17 00:00:00 2001 From: Roger Quadros <rogerq@xxxxxx> Date: Fri, 21 Apr 2017 15:58:08 +0300 Subject: usb: dwc3: gadget: Fix ISO transfer performance From: Roger Quadros <rogerq@xxxxxx> commit f1d6826cae30e97e37a1f2481d7e1dc4faa09ce1 upstream. Commit 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") caused a small change in the way ISO transfer is handled in the case when XferInProgress event happens on Isoc EP with an active transfer. This caused a performance degradation of 50%. e.g. using g_webcam on DUT and luvcview on host the video frame rate dropped from 16fps to 8fps @high-speed. Make the ISO transfer handling equivalent to that prior to that commit to get back the original ISO performance numbers. Fixes: 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") Signed-off-by: Roger Quadros <rogerq@xxxxxx> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/dwc3/gadget.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1258,14 +1258,24 @@ static int __dwc3_gadget_ep_queue(struct __dwc3_gadget_start_isoc(dwc, dep, cur_uf); dep->flags &= ~DWC3_EP_PENDING_REQUEST; } + return 0; } - return 0; + + if ((dep->flags & DWC3_EP_BUSY) && + !(dep->flags & DWC3_EP_MISSED_ISOC)) { + WARN_ON_ONCE(!dep->resource_index); + ret = __dwc3_gadget_kick_transfer(dep, + dep->resource_index); + } + + goto out; } if (!dwc3_calc_trbs_left(dep)) return 0; ret = __dwc3_gadget_kick_transfer(dep, 0); +out: if (ret == -EBUSY) ret = 0; Patches currently in stable-queue which might be from rogerq@xxxxxx are queue-4.11/usb-dwc3-gadget-fix-iso-transfer-performance.patch queue-4.11/mfd-omap-usb-tll-fix-inverted-bit-use-for-usb-tll-mode.patch