>> >> Split packet transactions are hidden. I could see them by clicking on >> >> the (Show/Hide Split transactions) button. For INT IN, I could see >> >> only Start Split packet. >> >> >> >> I attached([2014-10-28 session 144012] Trace0003.rar) complete log for >> >> this scenario. >> > >> > How come the log doesn't contain any SOF packets? >> >> >> To avoid recording a huge quantity of data , I enabled the "Drop Start >> of Frames" filter in the recording options. > > Can you do it again, but this time keep the SOF packets? > > You don't have to post the entire analyzer log. Just extract 3 or 4 ms > from the middle, where it shows the SSPLITS but no CSPLITS for the > interrupt endpoints, and post only that portion. > I tried again, I keep getting STALL's but this time I see CSPLITS for the interrupt end points. [root@banunxcas29 ns06]# lsusb -t 1-1.5.1:1.2: No such file or directory 1-1.5.2:1.2: 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 51, If 0, Class=hub, Driver=hub/4p, 480M |__ Port 1: Dev 52, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 1: Dev 52, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 1: Dev 52, If 2, Class=app., Driver=, 12M |__ Port 2: Dev 53, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 2: Dev 53, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 2: Dev 53, If 2, Class=app., Driver=, 12M |__ Port 3: Dev 56, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 3: Dev 56, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 3: Dev 56, If 2, Class=app., Driver=, 12M |__ Port 4: Dev 55, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 4: Dev 55, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M |__ Port 4: Dev 55, If 2, Class=app., Driver=, 12M Here Dev 51 is external USB-2 hub. usbmon log: ffff8800b2cce6c0 1558099725 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 1558099740 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 1558435684 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 1558435700 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 1558447773 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 1558447790 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 1562003759 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 1562003777 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 1835091798 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 1835091818 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2360295770 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2360295785 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2360307814 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2360307827 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2746327776 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2746327796 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2750455832 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2750455844 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2751751777 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2751751788 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2752707689 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2752707707 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2762271761 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2762271776 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 2977131824 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 2977131835 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 3602679779 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 3602679798 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 456023739 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 456023758 S Ii:1:055:1 -115:1 16 < ffff8800b2cce6c0 456231695 C Ii:1:055:1 -32:1 0 ffff8800b2cce6c0 456231712 S Ii:1:055:1 -115:1 16 < Dev 55 usb log: SSPLIT IN transaction 55 1 HS No data 0.000 238 117 Start of Frame (2) HS 228.0 -> 228.1 0.000 340 583 CSPLIT IN transaction 55 1 NAK HS No data 0.000 489 817 Start of Frame (6) HS 228.2 -> 228.7 0.000 590 617 SSPLIT IN transaction 55 1 HS No data 0.001 238 117 Start of Frame (2) HS 229.0 -> 229.1 0.001 340 733 CSPLIT IN transaction 55 1 NAK HS No data 0.001 489 850 Start of Frame (6) HS 229.2 -> 229.7 0.001 590 767 SSPLIT IN transaction 55 1 HS No data 0.002 238 933 Start of Frame (2) HS 230.0 -> 230.1 0.002 340 867 CSPLIT IN transaction 55 1 NAK HS No data 0.002 489 933 Start of Frame (6) HS 230.2 -> 230.7 0.002 590 900 SSPLIT IN transaction 55 1 HS No data 0.003 238 967 Start of Frame (2) HS 231.0 -> 231.1 0.003 341 017 CSPLIT IN transaction 55 1 NAK HS No data 0.003 489 900 Start of Frame (6) HS 231.2 -> 231.7 0.003 591 050 SSPLIT IN transaction 55 1 HS No data 0.004 238 950 Start of Frame (2) HS 232.0 -> 232.1 0.004 341 150 CSPLIT IN transaction 55 1 NAK HS No data 0.004 489 950 Start of Frame (6) HS 232.2 -> 232.7 0.004 591 183 SSPLIT IN transaction 55 1 HS No data 0.005 239 000 Start of Frame (2) HS 233.0 -> 233.1 0.005 341 283 CSPLIT IN transaction 55 1 NAK HS No data 0.005 490 000 External USB-2 hub (Dev 51) log: Start of Frame (570) HS 258.7 -> 330.0 0.000 090 550 IN transaction 51 1 NAK HS No data 0.071 226 050 Start of Frame (2,048) HS 299.0 -> 554.7 0.071 350 517 IN transaction 51 1 NAK HS No data 0.327 261 817 Start of Frame (2,048) HS 555.0 -> 810.7 0.327 386 250 IN transaction 51 1 NAK HS No data 0.583 297 550 Start of Frame (2,048) HS 811.0 -> 1,066.7 0.583 422 000 IN transaction 51 1 NAK HS No data 0.839 333 283 Start of Frame (2,048) HS 1,067.0 -> 1,322.7 0.839 457 733 IN transaction 51 1 NAK HS No data 1.095 369 050 Start of Frame (2,048) HS 1,323.0 -> 1,578.7 1.095 493 483 IN transaction 51 1 NAK HS No data 1.351 404 767 Start of Frame (2,048) HS 1,579.0 -> 1,834.7 1.351 529 233 IN transaction 51 1 NAK HS No data 1.607 440 517 Internal USB-2 hub (Dev 2) log: Start of Frame (266) HS 258.7 -> 292.0 0.000 090 550 Incomplete IN transaction 2 1 INCOMPLETE HS No data 0.033 220 750 Start of Frame (2,048) HS 261.0 -> 516.7 0.033 345 200 Incomplete IN transaction 2 1 INCOMPLETE HS No data 0.289 256 517 Start of Frame (2,048) HS 517.0 -> 772.7 0.289 380 950 Incomplete IN transaction 2 1 INCOMPLETE HS No data 0.545 292 233 Start of Frame (2,048) HS 773.0 -> 1,028.7 0.545 416 683 Incomplete IN transaction 2 1 INCOMPLETE HS No data 0.801 328 000 [root@banunxcas29 ns06]# 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) [root@banunxcas29 ns06]# lsusb -v -s 1:1 | grep iSerial iSerial 1 0000:00:1a.0 Attached the files present under /sys/kernel/debug/usb/ehci/0000\:00\:1a.0/. Thanks, Naveen