On Fri, Aug 12, 2011 at 6:46 AM, Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> wrote: > On Fri, Aug 12, 2011 at 03:28:42AM +0200, Daniel Mack wrote: >> On Fri, Aug 12, 2011 at 1:50 AM, Matěj Laitl <matej@xxxxxxxx> wrote: >> > On 12. 8. 2011 Daniel Mack wrote: >> >> > This patch actually makes the sound playback _worse_. Now I get strange >> >> > squawks where previously at least first seconds of a song sounded >> >> > normally. >> >> > >> >> > However, I no longer get "zero length buffer submitted" or that "... >> >> > Weird." debug messages, only several megabytes of: (should I post these >> >> > somewhere?) >> >> > >> >> > xhci_hcd 0000:05:00.0: Giveback URB ffff880114cec000, len = 880, >> >> > expected = 1000, status = -115 >> >> > xhci_hcd 0000:05:00.0: Giveback URB ffff880114740000, len = 352, >> >> > expected = 1000, status = -115 >> >> > xhci_hcd 0000:05:00.0: underrun event on endpoint >> >> >> >> Might be the hardware doesn't like this. As I said, the patch is blindly >> >> written and I couldn't test it. Did you test this on a EHCI port as well? >> > >> > Good point, this patch distorts the playback also on the EHCI port. (the >> > playback seems to be 10 times slower than it should be) >> >> And it is only this *last* patch that causes it, yes? >> >> If that is the case, we need empty subframes in the middle of urbs, >> and we need to figure a way how to teach the XHCI driver to cope with >> that, too. > > By empty subframes, you mean zero-length frame buffers in the middle of > the URB, correct? Yep. > Andiry and Alan had some suggestions for how to fix > that, so I'll try to cook up a patch tomorrow. Then we'll have to > "unpeel" the debug patches and make sure the system is still usable. Good :) And I'll make a patch to make double-submission impossible in a nice way. Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
