Return-Path: MIME-Version: 1.0 In-Reply-To: References: <1413367888.7328.1.camel@linux-0dmf.site> Date: Wed, 15 Oct 2014 19:16:39 +0530 Message-ID: Subject: Re: btusb_intr_complete returns -EPIPE From: Naveen Kumar Parna To: Oliver Neukum Cc: Alan Stern , "linux-bluetooth@vger.kernel.org" , linux-usb@vger.kernel.org, acho@suse.com Content-Type: text/plain; charset=UTF-8 Sender: linux-usb-owner@vger.kernel.org List-ID: Hi Oliver, I tried this test in two different set of hardware configurations. i) I tried in multiple test systems which has EHCI-USB host controller on PCI card and internal USB 2.0 hub("rate-matching" hub). All the test systems with this configuration gives spurious stall packets. [lowerlayers@banunxcas29 ~]$ lspci | grep -i usb 00:1a.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05) 00:1d.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05) lsusb: Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub ii) I found different test systems which has OHCI-USB host controller on PCI card and internal USB 1.1 hub. All the test systems with this configuration are not producing stall packets. [lowerlayers@camunxcas11 ~]$ lspci | grep -i usb 00:02.0 USB Controller: nVidia Corporation CK804 USB Controller (rev a2) 00:02.1 USB Controller: nVidia Corporation CK804 USB Controller (rev a3) lsusb: Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 002: ID 0451:2077 Texas Instruments, Inc. TUSB2077 Hub My device is a full-speed device. So , stall packets are due to buggy USB 2.0 hub? Is there a chance of getting stall packets “If the device runs at low speed or full speed and is connected through a USB-2.0 hub”? If so it looks like hub driver issue right? If the hub is the problem… what will be the better solution? Is it possible to change internal hub? Thanks, Naveen On Wed, Oct 15, 2014 at 6:39 PM, Naveen Kumar Parna wrote: > EHCI controller on PCI card and hub("rate-matching" hub) also internal. > > Is it possible to change the internal hub? > > > > Thanks, > Naveen > > On Wed, Oct 15, 2014 at 3:41 PM, Oliver Neukum wrote: >> On Thu, 2014-10-09 at 10:31 -0400, Alan Stern wrote: >>> On Thu, 9 Oct 2014, Naveen Kumar Parna wrote: >>> >>> > Hi Oliver & Alan, >>> > >>> > >>> > >>> > Thanks for your inputs. >>> > >>> > >>> > >>> > I enabled the dynamic debugging for USB HC driver. Please correct me >>> > if I am wrong. >>> >>> Debugging the kernel (or doing anything else to the kernel, for that >>> matter) won't solve the problem if it is caused by a buggy hub. >> >> Indeed. Could you just try a different hub? >> >> Regards >> Oliver >> >> >>