On Thu, Oct 16, 2014 at 7:39 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 16 Oct 2014, Naveen Kumar Parna wrote: > >> > Indeed. However, it is possible to use an additional in between your >> > devices and the internal hub. >> > >> > Regards >> > Oliver >> > >> > >> >> >> Tested with this configuration(external hubs Dev 3, Dev 4, Dev 17, Dev >> 10) and got the same result. >> >> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> >> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> >> |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/6p, 480M >> >> |__ Port 5: Dev 3, If 0, Class=hub, Driver=hub/7p, 12M >> >> |__ Port 1: Dev 4, If 0, Class=hub, Driver=hub/7p, 12M > > This is not what Oliver meant. You have to use a USB-2 hub. And > having one of them is enough; you don't need two. > > Alan Stern > As suggested, I connected USB-2 hub(Dev 87) in between my devices and the internal hub. In this scenario also observed the STALL packets. I am interested in understanding the objective of this test, can you please help me? [lowerlayers@banunxcas29 ~]$ lsusb -t 1-1.5.1:1.2: No such file or directory 1-1.5.3:1.2: No such file or directory 1-1.5.4:1.2: No such file or directory /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/6p, 480M |__ Port 5: Dev 87, If 0, Class=hub, Driver=hub/4p, 480M |__ Port 1: Dev 88, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 1: Dev 88, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 1: Dev 88, If 2, Class=app., Driver=, 12M |__ Port 3: Dev 90, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 3: Dev 90, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 3: Dev 90, If 2, Class=app., Driver=, 12M |__ Port 4: Dev 89, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 4: Dev 89, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 4: Dev 89, If 2, Class=app., Driver=, 12M [root@banunxcas29 ~]# cat /sys/kernel/debug/usb/usbmon/1u ffff8800b2036540 2419900733 C Ii:1:090:1 -32:1 0 ffff8800b2036540 2419900753 S Ii:1:090:1 -115:1 16 < ffff8800b2036540 963424773 C Ii:1:090:1 -32:1 0 ffff8800b2036540 963424792 S Ii:1:090:1 -115:1 16 < ffff8800b2036540 963448864 C Ii:1:090:1 -32:1 0 ffff8800b2036540 963448880 S Ii:1:090:1 -115:1 16 < /var/log/kernel Oct 27 13:21:15 banunxcas29 kernel: [1017571.251514] hci2 urb ffff8800b2036540 status -32 count 0 Oct 27 14:05:15 banunxcas29 kernel: [1020211.003086] hci2 urb ffff8800b2036540 status -32 count 0 Oct 27 14:05:15 banunxcas29 kernel: [1020211.027178] hci2 urb ffff8800b2036540 status -32 count 0 Thanks, Naveen -- 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