Commit 77d815df authored Apr 21, 2017 by Roger Quadros Committed by Gerrit - the friendly Code Review server Nov 22, 2017

usb: dwc3: gadget: Fix ISO transfer performance



Commit 08a36b54 ("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: 08a36b54 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()")
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Git-commit: f1d6826cae30e97e37a1f2481d7e1dc4faa09ce1
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Change-Id: I4f45206539ca3636531f869baff3940d91c7e77f

parent 1819d0ab

drivers/usb/dwc3/gadget.c

+11 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1321,10 +1321,19 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep dep, struct dwc3_request req)
	__dwc3_gadget_start_isoc(dwc, dep, cur_uf);		__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
	dep->flags &= ~DWC3_EP_PENDING_REQUEST;		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))		if (!dwc3_calc_trbs_left(dep))
	return 0;		return 0;

	@@ -1333,6 +1342,7 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep dep, struct dwc3_request req)
	dwc3_trace(trace_dwc3_gadget,		dwc3_trace(trace_dwc3_gadget,
	"%s: failed to kick transfers",		"%s: failed to kick transfers",
	dep->name);		dep->name);
			out:
	if (ret == -EBUSY)		if (ret == -EBUSY)
	ret = 0;		ret = 0;