From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.axiontech.ca (unknown [207.164.255.36]) by lists.ozlabs.org (Postfix) with ESMTP id 829751A0257 for ; Tue, 10 Feb 2015 10:21:48 +1100 (AEDT) From: Michael Tessier To: Alan Stern Subject: RE: PROBLEM: USB isochronous urb leak on EHCI driver Date: Mon, 9 Feb 2015 23:21:45 +0000 Message-ID: <66A26A9AA227D947AF088537F041526E224CCB@VSVR-EX10-MB1.pocatec.com> References: <66A26A9AA227D947AF088537F041526E2009E5@VSVR-EX10-MB1.pocatec.com> In-Reply-To: Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Cc: "linuxppc-dev@lists.ozlabs.org" , "linux-usb@vger.kernel.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > > > > > > That is interresting, however, I have an older kernel running=20 > > > > > > an OHCI driver which is able to handle 4 codecs. Same usb=20 > > > > > > hardware (codecs and hub), but older kernel on a different=20 > > > > > > CPU, with much less power. This makes me believe that there's a= solution to make it work... > > > > >=20 > > > > > Of course there is: Install an OHCI host controller and use it to= drive your codecs. It should work fine. > >=20 > > What do you mean by that? The host controller is embedded in the i.MX C= PU... > > Changing the CPU is not really an option to me. Unless I am missing=20 > > something? > > I didn't realize you were talking about an i.MX-based system. On a compu= ter with a free PCI slot, it's easy to add an OHCI controller. =20 > iMX isn't as accomodating. > > If there's no way to add an extra USB controller to your system then the = only choice is to upgrade the driver software. > > Alan Stern Okay; I did my homeworks. We've loaded kernel V3.16 (Oct 14th, 2015) on an = i.MX51 plattform and the problem is still there. Unless an important change= occured in V3.19, it appears that the latest kernel is not the solution fo= r us. So we're still not able to use 4 codecs on our i.MX plattform. So just to make things clearer: - We have customers waiting for a solution with that hardware (this hardwar= e is already delivred AND used); - We have important comittments and severe penalties ($$$) if we're not abl= e to deliver on time (due for March 15th); - We've already looked at a hardware solution, which corresponds to replace= current units ($$$$$), so that is not really an option for us; So as a last resort, I'm wondering, where is the USB expert who could help = us solving our problem? Any suggestions? If we are to get into debugging the USB driver, we would do it with the cur= rent kernel used (V2.6.31). What are the better tools to get into that? I g= uess a USB analyzer (hardware) would be the smart thing? Any brand name to = suggest? Any other ideas for a solution will be really appreciated. Regards, Michael Tessier.