USB_Analysis

https://www.kernel.org/doc/Documentation/usb/usbmon.txt

http://www.linux-usb.org/usb.ids




 mount -t debugfs none_debugs /sys/kernel/debug
 modprobe usbmon
  
 jaguar-ThinkPad-T540p usbmon # pwd
/sys/kernel/debug/usb/usbmon
jaguar-ThinkPad-T540p usbmon # ls
0s  0u  1s  1t  1u  2s  2t  2u  3s  3t  3u  4s  4t  4u

 
  
   sysfs structures for Linux USB:
   
   
   jaguar@jaguar-ThinkPad-T540p ~ $ ls   /sys/bus/usb/devices/
1-0:1.0  1-12:1.0  1-3      1-7      2-0:1.0  3-1      4-0:1.0  4-1:1.0  usb2  usb4
1-12     1-12:1.1  1-3:1.0  1-7:1.0  3-0:1.0  3-1:1.0  4-1      usb1     usb3

USB-controllers:
The names that begin with "usb" refer to USB controllers.
More accurately, they refer to the "root hub" associated with each controller. 
usb1 ---> root hub of usb-controller. It's bus number is 1. //bus1-port0(not actually a port) is used to refer roothub of bus1
usb2 ---> root hub of usb-controller. It's bus number is 2

USB devices:   bus-port.port.port....
eg: 1-2.3.1 ==> bus1(root-hub) - device plugged into port2 of root-hub.This device is another hub
=> device plugged into port3 of that hub.this device is another hub
==> device plugged into port1 of that hub.this device is not a hub.
simply 1-2.3.1 == device plugged into : bus1--port2 of root-hub .port3 of 1st level-hub . port1 of 2nd level hub.

1-12 ---->  bus1 - port12  : device is attached to the port12 of roothub
4-1  ---->  bus4 - port1   : device is attached to port1 of roothub

Interfaces of devices :  bus-port.port.port..... :config.interface
Each interface gets its own entry in sysfs and can have its own driver.

eg:     1-2.3:1.0	 ==> device plugged into : bus1--port2 of root-hub .port3 of 1st level-hub . port1 of 2nd level hub
              device is using configuration 1 and this configuration has only a single interface, number 0.
1-12:1.1 

Special case : ROOT-HUB's interface
A hub will never have more than a single interface; that's part of the USB spec. 
But other devices can have multiple interfaces (and sometimes multiple configurations)
 eg: "1-0:1.0"  It refers to the root hub's interface. 
This acts just like the interface in an actual hub an almost every respec
1-0:1.0 -->  bus1-port0 is used to refer roothub of bus1 -- here roothub is part of controller,not actually a port.
2-0:1.0 
3-0:1.0
4-0:1.0



jaguar@jaguar-ThinkPad-T540p ~ $ cat   /sys/bus/usb/devices/1-3:1.0/bInterfaceClass
fe
jaguar@jaguar-ThinkPad-T540p ~ $ cat   /sys/bus/usb/devices/1-3:1.0/bInterfaceNumber
00
jaguar@jaguar-ThinkPad-T540p ~ $ cat   /sys/bus/usb/devices/1-3:1.0/bInterfaceProtocol
00
jaguar@jaguar-ThinkPad-T540p ~ $ cat   /sys/bus/usb/devices/1-3:1.0/bInterfaceSubClass
01
jaguar@jaguar-ThinkPad-T540p ~ $ cat   /sys/bus/usb/devices/1-3:1.0/bNumEndpoints
00













  
  
  
  cat /proc/bus/usb/devices : find the T-line which corresponds tothe device
  lsusb
  
  
  # cat /sys/kernel/debug/usbmon/3u > /tmp/1.mon.out

to listen on a single bus, otherwise, to listen on all buses, type:

# cat /sys/kernel/debug/usbmon/0u > /tmp/1.mon.out
 

sudo tshark -D







jaguar@jaguar-ThinkPad-T540p ~ $ sudo tshark -D
Running as user "root" and group "root". This could be dangerous.
tshark: Lua: Error during loading:
 [string "/usr/share/wireshark/init.lua"]:44: dofile has been disabled due to running Wireshark as superuser. See https://wiki.wireshark.org/CaptureSetup/CapturePrivileges for help in running Wireshark as an unprivileged user.
1. wlan0
2. nflog
3. nfqueue
4. pan1
5. usbmon1
6. usbmon2
7. usbmon3
8. usbmon4
9. any
10. lo (Loopback)

jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 005: ID 0471:df55 Philips (or NXP) LPCXpresso LPC-Link
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

to capture 0471:df55 on bus 1 ----- in a file trace1.pcap

jaguar@jaguar-ThinkPad-T540p ~ $ tshark -i usbmon2 -w trace1.pcap 
Capturing on 'usbmon2'
tshark: Couldn't run /usr/bin/dumpcap in child process: Permission denied

jaguar@jaguar-ThinkPad-T540p ~ $ sudo tshark -i usbmon1 -w ~/trace1.pcap 
Running as user "root" and group "root". This could be dangerous.
tshark: Lua: Error during loading:
 [string "/usr/share/wireshark/init.lua"]:44: dofile has been disabled due to running Wireshark as superuser. See https://wiki.wireshark.org/CaptureSetup/CapturePrivileges for help in running Wireshark as an unprivileged user.
Capturing on 'usbmon1'
tshark: The file to which the capture would be saved ("/home/jaguar/trace1.pcap") could not be opened: Permission denied.



When a device plugs into a port, the device’s pull-up brings its line high,
enabling the hub to detect that a device is attached
The hub detects the device.

Each hub uses its interrupt endpoint
to report events at the hub. The report indicates only whether the hub or a
port (and if so, which port) has experienced an event



URB-status-word:=> 
(URB status, interval, start frame, and error count)
a letter/several numbers separated by colon 
(all fields except the status are optional : Interval is printed  only for interrupt and isochronous URBs. Start frame is printed only for
  isochronous URBs,Error count is printed only for isochronous callback  events.)

URB status : number
              This field makes no sense for submissions
              In case of a submission of a Control packet, this field contains a Setup Tag
              
if Setup Tag was 's': then only decode below
Setup packet : ( bmRequestType, bRequest, wValue, wIndex, wLength):as per USB-2.0.

ffff8801f6e0a6c0 3824618392 C Ii:1:001:1 0:2048 2 = 4000
explaination:
C - callback event 
Ii:1:001:1   ====   Interrupt : IN : bus-1 : device-1 : endpoint-1   // bus1,dev-1 is HUB.
URB type and direction, Bus number, Device address, Endpoint number

0:2048
status-0: Interval-2048

---------------------------------------------------------------------------------------------------------

ffff8801f6e0a6c0 3824618402 S Ii:1:001:1 -115:2048 4 <
S - setup event 
Ii:1:001:1   ====   Interrupt : IN : bus-1 : device-1 : endpoint-1   // bus1,dev-1 is HUB.
URB type and direction, Bus number, Device address, Endpoint number

-115:2048 
status-EINPROGRESS: Interval-2048
 
 4 <  
 requested data length =4
 -----------------------------------------------------------------------------------------------------------------
 
 ffff8800b5c8fa80 3824618413 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
 S - setup event 
 Ci:1:001:0   ====   Control : IN : bus-1 : device-1 : endpoint-0
 
 s 
 Setup Tag
 
 a3 00 0000 0006 0004
 bmRequestType = a3 , bRequest =00 , wValue=0000, wIndex=0006, wLength=0004
 
 bmRequestType: direction of data flow, the type of request, and the recipient.
 1(OUT/IN)010(standard/class-specific/vendor-specific)0011
 a3 = 1010 0011   ===> 1(dev->host) 01(class)  00011(other element in device)
 
 bRequest: 00 (GET_STATUS)
 wValue : request-specific value -
 wIndex : enpoint-index/interface-index  --- endpoint 6 => port6
 wLength: number of data bytes in the Data stage that follow
 
 
 
 
 
 
 
 
 
 
              
              
              





















Data transactions occur in three phases: Token, Data, and Handshake.

All communication on the USB is host-directed. 

In the Token phase, the host will generate a Token packet which will address a specific device/endpoint combination.
A Token packet can be IN, OUT, or SETUP.

IN  :  The host is requesting data from the addressed dev/ep.

OUT : The host is sending data to the addressed dev/ep.

SETUP:  The host is transmitting control information to the device.

In the data phase, the transmitter will send one data packet.
For IN requests, the device may send a NAK or STALL packet during the data phase to 
indicate that it isn’t able to service the token that it received.

 in the Handshake phase the receiver can send an ACK, NAK, or STALL indicating the success or failure of the transaction.
 
 All of the transfers described above follow this general scheme with the exception of the Isochronous transfer.
 In this case, no Handshake phase occurs because it is more important to stream data out in a timely fashion.
 It is acceptable to drop packets occasionally and there is no need to waste time by attempting to retransmit.
 
 
 
 
 



cat 1u > ~/link.mon
vusb-analyzer ~/link.mon

USB class/device drivers communicate with USB host controllers by submitting URBs.
Each URB request host controller to send/rxv data to/from  an EP on device.
host controller schedules the request on the bus and notifies the driver when request completes.

URB submission to USB-subsystem:
usb_submit_urb :  submits URB and transfers control of the URB ,describing that request ,to the USB subsystem
If the submission is successful, the complete callback from the URB will be called exactly once, 
when the USB core and Host Controller Driver (HCD) are finished with the URB. 
When the completion function is called, control of the URB is returned to the device driver which issued the request. 
The completion handler may then immediately free or reuse that URB. 






ffff8801f6e36480 1880200748 C Ii:1:001:1 0:2048 2 = 0800
ffff8801f6e36480 1880200759 S Ii:1:001:1 -115:2048 4 <
ffff8801f5393540 1880200792 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880200803 C Ci:1:001:0 0 4 = 01010100
ffff8801f5393540 1880200807 S Co:1:001:0 s 23 01 0010 0003 0000 0
ffff8801f5393540 1880200816 C Co:1:001:0 0 0
ffff8801f5393540 1880200824 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880200839 C Ci:1:001:0 0 4 = 01010000
ffff8801f5393540 1880230373 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880230388 C Ci:1:001:0 0 4 = 01010000
ffff8801f5393540 1880262368 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880262384 C Ci:1:001:0 0 4 = 01010000
ffff8801f5393540 1880294432 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880294460 C Ci:1:001:0 0 4 = 01010000
ffff8801f5393540 1880326439 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880326465 C Ci:1:001:0 0 4 = 01010000
ffff8801f5393540 1880326556 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8801f5393540 1880326586 C Co:1:001:0 0 0
ffff8801f5393540 1880382396 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880382426 C Ci:1:001:0 0 4 = 03051000
ffff8801f5393540 1880382439 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8801f5393540 1880382455 C Co:1:001:0 0 0
ffff8801f5393540 1880438526 S Ci:1:000:0 s 80 06 0100 0000 0040 64 <
ffff8801f5393540 1880438700 C Ci:1:000:0 0 18 = 12010002 00000040 710455df 01000000 0001
ffff8801f5393540 1880438780 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8801f5393540 1880438806 C Co:1:001:0 0 0
ffff8801f5393540 1880494395 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880494429 C Ci:1:001:0 0 4 = 03051000
ffff8801f5393540 1880494441 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8801f5393540 1880494456 C Co:1:001:0 0 0
ffff8801f5393540 1880566429 S Ci:1:010:0 s 80 06 0100 0000 0012 18 <
ffff8801f5393540 1880566631 C Ci:1:010:0 0 18 = 12010002 00000040 710455df 01000000 0001
ffff8801f5393540 1880566674 S Ci:1:010:0 s 80 06 0200 0000 0009 9 <
ffff8801f5393540 1880566863 C Ci:1:010:0 0 9 = 09021900 01010080 32
ffff8801f5393540 1880566897 S Ci:1:010:0 s 80 06 0200 0000 0019 25 <
ffff8801f5393540 1880567111 C Ci:1:010:0 0 25 = 09021900 01010080 32090400 0000fe01 00000721 01ffff00 08
ffff8801f5393600 1880567333 S Co:1:010:0 s 00 09 0001 0000 0000 0
ffff8801f5393600 1880567452 C Co:1:010:0 0 0










decoding URB with Id: ffff8801f5393540

ffff8801f5393540 1880200792 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <

S: Event is an URB submission :

Ci:1:001:0  ==> driver is  submitting control request for IN data to bus1-dev1-Ep0

s a3 00 0000 0003 0004 ==>   setup-stage-data: bmRequestType,bRequest,wValue,wIndex,wLength
                             
                             req-direction:dev-host,req for a specific class,req to other element in device. 
 
                             request = GET_STATUS

                             Endpoint = 03  which is OUT ep  

                             number of data bytes in the Data stage that follow = 4

===> Host initiated control transfer by sending setup type token packet.
     token indicates device should transmit the status of EP-3

setup stage of Control-IN transfer is completed.

ffff8801f5393540 1880200803 C Ci:1:001:0 0 4 = 01010100

 C : Event is URB-callback

 C Ci:1:001:0   ==> call-back event of URB-submitted for control request for IN data to bus1-dev1-Ep0
 0 => URB's status is success.
 4 => data bytes recieved in the data stage .
01010100 ==> EP3 status of bus1-dev1

==> device recieved the control-IN request and replied with control-info requested,successfully.




ffff8801f5393540 1880200807 S Co:1:001:0 s 23 01 0010 0003 0000 0
setup stage of control-OUT request : to bus1-dev1-ep0 : host-dev-->clear-feature request for ep3
                                    feature =10 (C_PORT_CONNECTION) , no data-stage follows

====>  host sent control-OUT request to device asking for clear-C_PORT_CONNECTION : disable the feature(connection status)on ep3.


ffff8801f5393540 1880200816 C Co:1:001:0 0 0 
--> call back event--of URB-submitted for OUT-control request--success.

 


ffff8801f5393540 1880200824 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880200839 C Ci:1:001:0 0 4 = 01010000
get-status( dev-->host),ep3 
success : 01010000 -->

Above is repeted 5 times..


ffff8801f5393540 1880326556 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8801f5393540 1880326586 C Co:1:001:0 0 0

(host-->dev)Set_Feature : PORT_RESET -reset processing is not yet completed.
success.


ffff8801f5393540 1880382396 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880382426 C Ci:1:001:0 0 4 = 03051000
setup-CTRL-IN-Get_status of ep3
successfull - status = 03051000


ffff8801f5393540 1880382439 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8801f5393540 1880382455 C Co:1:001:0 0 0
setup-CTRL-out:CLEAR_FEATURE= C_PORT_RESET -


ffff8801f5393540 1880438526 S Ci:1:000:0 s 80 06 0100 0000 0040 64 <
ffff8801f5393540 1880438700 C Ci:1:000:0 0 18 = 12010002 00000040 710455df 01000000 0001
setup-CTRL-IN: 
 80= 1000 0000 = 1 00 0000 => dev->host,std-req,req to device.
 06 --> get_descriptor
0100 -->00 01 --.> bDescriptorType =01 ==> device descriptor type.
64 bytes of data expecting in data stage

success : 18 bytes



ffff8801f5393540 1880438780 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8801f5393540 1880438806 C Co:1:001:0 0 0
h->dev:SET_FEATURE : PORT_RESET

ffff8801f5393540 1880494395 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8801f5393540 1880494429 C Ci:1:001:0 0 4 = 03051000
dev-->host GET_STATUS :ep3

ffff8801f5393540 1880494441 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8801f5393540 1880494456 C Co:1:001:0 0 0
host-->dev  clear_feature -C_PORT_RESET

ffff8801f5393540 1880566429 S Ci:1:010:0 s 80 06 0100 0000 0012 18 <
ffff8801f5393540 1880566631 C Ci:1:010:0 0 18 = 12010002 00000040 710455df 01000000 0001







#########################################################################################










jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M
    |__ Port 7: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 12: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
    |__ Port 12: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M


jaguar@jaguar-ThinkPad-T540p ~ $ ls  /sys/bus/usb/devices/
1-0:1.0  1-12:1.0  1-7      2-0:1.0  3-1      4-0:1.0  4-1:1.0  usb2  usb4
1-12     1-12:1.1  1-7:1.0  3-0:1.0  3-1:1.0  4-1      usb1     usb3
jaguar@jaguar-ThinkPad-T540p ~ $ 

jaguar@jaguar-ThinkPad-T540p ~ $ ls  /sys/bus/usb/devices/

usb1  --> usb controller
1-0:1.0  root-hub --part of usb1-controller/not a port
1-12  ----> Accer camera @ bus1-port12
1-12:1.0 -- interface 0 of accer camera to port 12 of bus1
1-12:1.1 -- interface 1 of accer camera to port 12 of bus1
1-7    -----validity sensors@ bus1-port7
1-7:1.0 ----validity sensors: bus1-port7

2-0:1.0

3-1   
3-0:1.0  
3-1:1.0  

4-0:1.0
4-1:1.0 
4-1   

usb2  usb3 usb4




jaguar@jaguar-ThinkPad-T540p ~ $ ls -l   /sys/bus/usb/devices/
total 0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12:1.1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-7 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-7:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 2-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb2/2-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-0:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-1 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-1:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-1 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-1:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb2 -> ../../../devices/pci0000:00/0000:00:14.0/usb2
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb3 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb4 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4


jaguar@jaguar-ThinkPad-T540p ~ $ ls -l   /sys/bus/usb/drivers
total 0
drwxr-xr-x 2 root root 0 Aug  6 17:23 btusb
drwxr-xr-x 2 root root 0 Aug  6 17:23 hub
drwxr-xr-x 2 root root 0 Aug  6 17:23 uas
drwxr-xr-x 2 root root 0 Aug  6 17:23 usb
drwxr-xr-x 2 root root 0 Aug  6 17:23 usbfs
drwxr-xr-x 2 root root 0 Aug  6 17:23 usbhid
drwxr-xr-x 2 root root 0 Aug  6 17:23 usb-storage
drwxr-xr-x 2 root root 0 Aug  6 17:23 uvcvideo

jaguar@jaguar-ThinkPad-T540p ~ $ ls -l   /sys/bus/usb/drivers/usb
total 0
lrwxrwxrwx 1 root root    0 Aug  6 17:24 1-12 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1/1-12
lrwxrwxrwx 1 root root    0 Aug  6 17:24 1-7 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1/1-7
lrwxrwxrwx 1 root root    0 Aug  6 17:24 3-1 -> ../../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1
lrwxrwxrwx 1 root root    0 Aug  6 17:24 4-1 -> ../../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1
--w------- 1 root root 4096 Aug  6 17:24 bind
--w------- 1 root root 4096 Aug  6 17:24 uevent
--w------- 1 root root 4096 Aug  6 17:24 unbind
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb1 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb2 -> ../../../../devices/pci0000:00/0000:00:14.0/usb2
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb3 -> ../../../../devices/pci0000:00/0000:00:1a.0/usb3
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb4 -> ../../../../devices/pci0000:00/0000:00:1d.0/usb4
jaguar@jaguar-ThinkPad-T540p ~ $ 







jaguar-ThinkPad-T540p usbmon # cat ~/link.mon
ffff8801f6e36480 169368299 C Ii:1:001:1 0:2048 2 = 0800
ffff8801f6e36480 169368319 S Ii:1:001:1 -115:2048 4 <
ffff8800c8ce5000 169368408 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169368428 C Ci:1:001:0 0 4 = 01010100
ffff8800c8ce5000 169368438 S Co:1:001:0 s 23 01 0010 0003 0000 0
ffff8800c8ce5000 169368453 C Co:1:001:0 0 0
ffff8800c8ce5000 169368461 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169368503 C Ci:1:001:0 0 4 = 01010000
ffff8800c8ce5000 169398438 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169398468 C Ci:1:001:0 0 4 = 01010000
ffff8800c8ce5000 169430417 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169430443 C Ci:1:001:0 0 4 = 01010000
ffff8800c8ce5000 169462445 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169462480 C Ci:1:001:0 0 4 = 01010000
ffff8800c8ce5000 169494368 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169494390 C Ci:1:001:0 0 4 = 01010000
ffff8800c8ce5000 169494446 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8800c8ce5000 169494462 C Co:1:001:0 0 0
ffff8800c8ce5000 169550437 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169550465 C Ci:1:001:0 0 4 = 03051000
ffff8800c8ce5000 169550474 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8800c8ce5000 169550489 C Co:1:001:0 0 0
ffff8800c8ce5000 169606486 S Ci:1:000:0 s 80 06 0100 0000 0040 64 <
ffff8800c8ce5000 169606646 C Ci:1:000:0 0 18 = 12010002 00000040 710455df 01000000 0001
ffff8800c8ce5000 169606682 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8800c8ce5000 169606709 C Co:1:001:0 0 0
ffff8800c8ce5000 169662395 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8ce5000 169662426 C Ci:1:001:0 0 4 = 03051000
ffff8800c8ce5000 169662435 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8800c8ce5000 169662449 C Co:1:001:0 0 0
ffff8800c8ce5000 169734381 S Ci:1:014:0 s 80 06 0100 0000 0012 18 <
ffff8800c8ce5000 169734579 C Ci:1:014:0 0 18 = 12010002 00000040 710455df 01000000 0001
ffff8800c8ce5000 169734613 S Ci:1:014:0 s 80 06 0200 0000 0009 9 <
ffff8800c8ce5000 169734869 C Ci:1:014:0 0 9 = 09021900 01010080 32
ffff8800c8ce5000 169734921 S Ci:1:014:0 s 80 06 0200 0000 0019 25 <
ffff8800c8ce5000 169735169 C Ci:1:014:0 0 25 = 09021900 01010080 32090400 0000fe01 00000721 01ffff00 08
ffff8800c8ce59c0 169735461 S Co:1:014:0 s 00 09 0001 0000 0000 0
ffff8800c8ce59c0 169735565 C Co:1:014:0 0 0



























jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M
    |__ Port 3: Dev 14, If 0, Class=Application Specific Interface, Driver=, 480M
    |__ Port 7: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 12: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
    |__ Port 12: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 014: ID 0471:df55 Philips (or NXP) LPCXpresso LPC-Link
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls  /sys/bus/usb/devices/
1-0:1.0  1-12:1.0  1-3      1-7      2-0:1.0  3-1      4-0:1.0  4-1:1.0  usb2  usb4
1-12     1-12:1.1  1-3:1.0  1-7:1.0  3-0:1.0  3-1:1.0  4-1      usb1     usb3
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls -l   /sys/bus/usb/devices/
total 0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-12:1.1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.1
lrwxrwxrwx 1 root root 0 Aug  6 17:27 1-3 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-3
lrwxrwxrwx 1 root root 0 Aug  6 17:27 1-3:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-7 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7
lrwxrwxrwx 1 root root 0 Aug  6 17:23 1-7:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 2-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb2/2-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-0:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-1 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 3-1:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-0:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-1 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 4-1:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1:1.0
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb2 -> ../../../devices/pci0000:00/0000:00:14.0/usb2
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb3 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3
lrwxrwxrwx 1 root root 0 Aug  6 17:23 usb4 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls -l   /sys/bus/usb/drivers/usb
total 0
lrwxrwxrwx 1 root root    0 Aug  6 17:24 1-12 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1/1-12
lrwxrwxrwx 1 root root    0 Aug  6 17:28 1-3 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1/1-3
lrwxrwxrwx 1 root root    0 Aug  6 17:24 1-7 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1/1-7
lrwxrwxrwx 1 root root    0 Aug  6 17:24 3-1 -> ../../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1
lrwxrwxrwx 1 root root    0 Aug  6 17:24 4-1 -> ../../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1
--w------- 1 root root 4096 Aug  6 17:24 bind
--w------- 1 root root 4096 Aug  6 17:24 uevent
--w------- 1 root root 4096 Aug  6 17:24 unbind
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb1 -> ../../../../devices/pci0000:00/0000:00:14.0/usb1
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb2 -> ../../../../devices/pci0000:00/0000:00:14.0/usb2
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb3 -> ../../../../devices/pci0000:00/0000:00:1a.0/usb3
lrwxrwxrwx 1 root root    0 Aug  6 17:24 usb4 -> ../../../../devices/pci0000:00/0000:00:1d.0/usb4
jaguar@jaguar-ThinkPad-T540p ~ $ 


###########################################################################################################3



jaguar@jaguar-ThinkPad-T540p ~ $ lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M
    |__ Port 7: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 12: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
    |__ Port 12: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M

jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls  /sys/bus/usb/devices/
1-0:1.0  1-12  1-12:1.0  1-12:1.1  1-7  1-7:1.0  2-0:1.0  3-0:1.0  3-1  3-1:1.0  4-0:1.0  4-1  4-1:1.0  usb1  usb2  usb3  usb4
jaguar@jaguar-ThinkPad-T540p ~ $ 

usb1  --> usb controller
1-0:1.0  root-hub --part of usb1-controller/not a port
1-12  ----> Accer camera @ bus1-port12
1-12:1.0 -- interface 0 of accer camera to port 12 of bus1
1-12:1.1 -- interface 1 of accer camera to port 12 of bus1
1-7    -----validity sensors@ bus1-port7
1-7:1.0 ----validity sensors: bus1-port7

2-0:1.0

3-1   
3-0:1.0  
3-1:1.0  

4-0:1.0
4-1:1.0 
4-1   

usb2  usb3 usb4



jaguar-ThinkPad-T540p usbmon # cat ~/link.mon


URB-ffff8801f6e36480
addressing bus1-dev1-ep1 rootHUB-ep1 

ffff8801f6e36480 2403355872 C Ii:1:001:1 0:2048 2 = 0800
ffff8801f6e36480 2403355895 S Ii:1:001:1 -115:2048 4 <

Each hub uses its interrupt endpoint to report events at the hub.
 The report indicates only whether the hub or a port (and if so, which port) has experienced an event.

-EINPROGRESS = - 115 
 - Out of memory (-ENOMEM)
- Unplugged device (-ENODEV)
- Stalled endpoint (-EPIPE)
- Too many queued ISO transfers (-EAGAIN)
- Too many requested ISO frames (-EFBIG)
- Invalid INT interval (-EINVAL)
- More than one packet for INT (-EINVAL)



URB- ffff8800c8c10900
addressing bus1-dev1-ep0 rootHUB-ep0 

ffff8800c8c10900 2403355967 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403355987 C Ci:1:001:0 0 4 = 01010100
GET_STATUS

ffff8800c8c10900 2403355994 S Co:1:001:0 s 23 01 0010 0003 0000 0
ffff8800c8c10900 2403356008 C Co:1:001:0 0 0
CLEAR_FEATURE : C_PORT_CONNECTION

ffff8800c8c10900 2403356014 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403356025 C Ci:1:001:0 0 4 = 01010000
GET_STATUS

ffff8800c8c10900 2403386434 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403386460 C Ci:1:001:0 0 4 = 01010000
GET_STATUS

ffff8800c8c10900 2403418425 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403418450 C Ci:1:001:0 0 4 = 01010000
GET_STATUS

ffff8800c8c10900 2403450419 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403450442 C Ci:1:001:0 0 4 = 01010000
GET_STATUS

ffff8800c8c10900 2403482387 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403482408 C Ci:1:001:0 0 4 = 01010000
GET_STATUS

ffff8800c8c10900 2403482467 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8800c8c10900 2403482481 C Co:1:001:0 0 0
SET_FEATURE  : PORT_RESET 


ffff8800c8c10900 2403538391 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403538412 C Ci:1:001:0 0 4 = 03051000
GET_STATUS

ffff8800c8c10900 2403538420 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8800c8c10900 2403538431 C Co:1:001:0 0 0
CLEAR_FEATURE= C_PORT_RESET 


addressing bus1-dev0-ep0   LPC-link-ep-0 (Univeral-address 0 on bus1)

ffff8800c8c10900 2403594509 S Ci:1:000:0 s 80 06 0100 0000 0040 64 <
ffff8800c8c10900 2403594674 C Ci:1:000:0 0 18 = 12010002 00000040 710455df 01000000 0001
GET_DESCRIPTOR : DEVICE_DESCRIPTOR


addressing bus1-dev1-ep0 rootHUB-ep-0

ffff8800c8c10900 2403594723 S Co:1:001:0 s 23 03 0004 0003 0000 0
ffff8800c8c10900 2403594740 C Co:1:001:0 0 0
SET_FEATURE : PORT_RESET

ffff8800c8c10900 2403650385 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ffff8800c8c10900 2403650407 C Ci:1:001:0 0 4 = 03051000
GET_STATUS

ffff8800c8c10900 2403650415 S Co:1:001:0 s 23 01 0014 0003 0000 0
ffff8800c8c10900 2403650428 C Co:1:001:0 0 0
CLEAR_FEATURE= C_PORT_RESET 

addressing bus1-dev17-ep0 LPC-link-ep-0

ffff8800c8c10900 2403722370 S Ci:1:017:0 s 80 06 0100 0000 0012 18 <
ffff8800c8c10900 2403722547 C Ci:1:017:0 0 18 = 12010002 00000040 710455df 01000000 0001
GET_DESCRIPTOR=DEVICE

ffff8800c8c10900 2403722579 S Ci:1:017:0 s 80 06 0200 0000 0009 9 <
ffff8800c8c10900 2403722727 C Ci:1:017:0 0 9 = 09021900 01010080 32
GET_DESCRIPTOR=CONFIGURATION
CONFIGURATION DESCRIPTOR
    bLength: 9
    bDescriptorType: 0x02 (CONFIGURATION)
    wTotalLength: 25
    bNumInterfaces: 1
    bConfigurationValue: 1
    iConfiguration: 0
    Configuration bmAttributes: 0x80  NOT SELF-POWERED  NO REMOTE-WAKEUP
        1... .... = Must be 1: Must be 1 for USB 1.1 and higher
        .0.. .... = Self-Powered: This device is powered from the USB bus
        ..0. .... = Remote Wakeup: This device does NOT support remote wakeup
    bMaxPower: 50  (100mA)


ffff8800c8c10900 2403722758 S Ci:1:017:0 s 80 06 0200 0000 0019 25 <
ffff8800c8c10900 2403722964 C Ci:1:017:0 0 25 = 09021900 01010080 32090400 0000fe01 00000721 01ffff00 08
GET_DESCRIPTOR=CONFIGURATION
CONFIGURATION DESCRIPTOR
    bLength: 9
    bDescriptorType: 0x02 (CONFIGURATION)
    wTotalLength: 25
    bNumInterfaces: 1
    bConfigurationValue: 1
    iConfiguration: 0
    Configuration bmAttributes: 0x80  NOT SELF-POWERED  NO REMOTE-WAKEUP
        1... .... = Must be 1: Must be 1 for USB 1.1 and higher
        .0.. .... = Self-Powered: This device is powered from the USB bus
        ..0. .... = Remote Wakeup: This device does NOT support remote wakeup
    bMaxPower: 50  (100mA)
INTERFACE DESCRIPTOR (0.0): class Application Specific
    bLength: 9
    bDescriptorType: 0x04 (INTERFACE)
    bInterfaceNumber: 0
    bAlternateSetting: 0
    bNumEndpoints: 0
    bInterfaceClass: Application Specific (0xfe)
    bInterfaceProtocol: Device Firmware Upgrade (0x01)
    bInterfaceProtocol: Unknown (0x00)
    iInterface: 0
DFU Descriptor: DFU FUNCTIONAL
    bLength: 7
    bDescriptorType: 0x21 (DFU FUNCTIONAL)
    0000 .... = Reserved: 0x00
    .... 0... = Will Detach: False
    .... .0.. = Manifestation Tolerant: False
    .... ..0. = Can Upload: False
    .... ...1 = Can Download: True
    wDetachTimeOut: 65535
    wTransferSize: 2048



URB-ffff8800c8c10780
addressing bus1-dev14-ep0 LPC-link-ep-0

ffff8800c8c10780 2403723183 S Co:1:017:0 s 00 09 0001 0000 0000 0
ffff8800c8c10780 2403723295 C Co:1:017:0 0 0
SET_CONFIGURATION


jaguar@jaguar-ThinkPad-T540p ~ $ lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M
    |__ Port 3: Dev 17, If 0, Class=Application Specific Interface, Driver=, 480M
    |__ Port 7: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 12: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
    |__ Port 12: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M
jaguar@jaguar-ThinkPad-T540p ~ $ lsusb 
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 017: ID 0471:df55 Philips (or NXP) LPCXpresso LPC-Link
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls  /sys/bus/usb/devices/
1-0:1.0  1-12:1.0  1-3      1-7      2-0:1.0  3-1      4-0:1.0  4-1:1.0  usb2  usb4
1-12     1-12:1.1  1-3:1.0  1-7:1.0  3-0:1.0  3-1:1.0  4-1      usb1     usb3
jaguar@jaguar-ThinkPad-T540p ~ $ 

all hubs only have one interface; the interrupt interface to notify of events on the hub

Root Hub: The USB controller implements a root hub
The hub driver lives in drivers/usb/core/hub.c.
The USB initialisation function starts up the khubd thread which waits for and handles USB events.
(drivers/usb/core/hub.c:usb_hub_init()) 

hub driver setup:
usb_init() ---> usb_hub_init()--->usb_register_driver(): adds itself(hub-driver) to the USB bus and sets up usb_probe_device() 

The root hub setup : The Linux driver core goes through all devices on the PCI bus
including the USB host controller,and calls the probe() function registerd by deriver of host controller (uhci_hcd_init())

The USB host controller driver-->usb_hcd_pci_probe() --->does some generic setup, then calls back into the host driver start()
--->calls usb_add_hcd() which does some generic HCD setup and ends up calling register_root_hub().

register_root_hub() creates a new USB device and registers it with drivers/usb/core/hub.c
usb_new_device() first calls drivers/usb/core/config.c:usb_get_configuration which sets up the interface(Interrupt interface of hub)
 for the device before registering with the Linux driver core via drivers/base/core/device_add()-->which rescans USB bus




Binding root hub to a driver:

USB core  usb_init()-->usb_register_device_driver(): setting up usb_probe_device() --->driver_register
ore/device_add()-->which rescans USB bus-->driver core will now see this new device and start probing for a driver to handle it. 

usb_probe_device() of The USB generic drive is called back.This converts the Linux driver core device back to a USB device
 that was registered by register_root_hub()) and calls calls the drivers probe function generic_probe().


The role of the generic driver is to get the interfaces on the device up and running
 Firstly it calls :choose_configuration() which simply reads through the device data and chooses a sane configuration
how does it know what is a sane configuration for the root hub? All the information has been "faked" for the root hub in drivers/usb/core/hcd.c:usb2_rh_dev_descriptor and the like. The root hub details are defined by the USB specification, so these can be kept statically.

usb_set_configuration() is called to set up the chosen configuration.
It uses the helper function usb_control_message() to send a message to the device about what configuration mode to go into
It then goes through the available interfaces setting up the kernel structures, and adds them with device_add().


When a new interface is added, the driver core will now try and find a driver to handle it.
When an interface driver is registered with drivers/usb/core/driver.c:usb_register_driver() it sets the probe function to drivers/usb/core/driver.c:usb_probe_interface(). 

driver core calls this function, and the first thing it does is checks the ID against the IDs the driver is happy to handle from the drivers id_table: usb_match_one_id() :  match the class, subclass and protocol


The root hub is part of the hub class, so can be handled by the hub drive
 drivers/usb/core/hub.c:hub_probe() will be called to get the hub driver to bind with the new hub
hub_probe() ---> hub_configure() 
does  some setup . Interesting is setting up Interrupt end point of roothub.

The interrupt end-point on a hub will send an event whenever something happens on the hub, such as a device being plugged in or unplugged.
Interrupt end-point is setup:

This is done by creating a URB and binding it to the end-point, asking that hub_irq be called whenever this URB is complete (e.g. when an event is received).


New events on the hub:
 The root hub is setup and listening for new events - 
 plug in our device : host controller will raise an interrupt signalling that one of its ports has changed state.
 This will be handled by drivers/usb/host/uhci-hcd.c:uhci_irq() ---> uhci_scan_schedule()

uhci_scan_schedule : implements the interface between the UHCI "transfer data" messages and the Linux URB scheme
                    It goes through the queues and finds any complete URBs and calls their completion function

 kernel starts the khubd daemon to handle hub events. We can see that hub_irq does some simple error checking, but its real job is to notify khubd that there is a new event on this hub.
hub_events() is the khubd daemon thread doing all the work. Once notified the hub has new event, it goes and reads the hub status to see what to do. A new device appearing will trigger a port change event, which is handled by hub_port_connect_change(). This does some initial setup of the device, but most importantly now calls usb_new_device().

At this point, if the USB driver for this device is loaded, the device is essentially ready to go. As with the root hub, the device will be probed and its interfaces found with the generic driver, and then those interfaces will be registered and any driver asked if they wish to bind to them.




USB-Firmware samples helpfull:
####################################
for LPC1768:


jaguar@jaguar-ThinkPad-T540p ~/Downloads/FreeRTOS_demos/FreeRTOS_V9.0.0rc2/FreeRTOS/Demo/CORTEX_LPC1768_GCC_RedSuite/src/LPCUSB $ ls
type.h    USB_CDC.c     usbdebug.h   usbhw_lpc.h  usbstdreq.c
usbapi.h  usbcontrol.c  usbhw_lpc.c  usbinit.c    usbstruct.h


 TOS/Demo/CORTEX_LPC1768_GCC_RedSuite/src/LPCUSB $ ls /home/jaguar/Documents/Free
Rtos/nxp/lpcopen_proj1 | grep usb
lpcusblib_KeyboardHost lpcusblib_MassStorageHost usbd_lib_cdc usbd_lib_cdc_uart usbd_lib_composite
usbd_lib_hid_generic  usbd_lib_hid_keyboard  usbd_lib_hid_mouse 

####################################################
For Beagle-bone:

 ls /home/jaguar/Documents/Emb_linux/em_lin/practice/am335x_starterware/starterwarefree-code/examples/beaglebone
cache_mmu  gpio               rtc                   usb_dev_msc
demo       hsi2c_eeprom       uart                  usb_dev_serial
dmtimer    hsi2c_eeprom_edma  uart_edma             usb_host_msc
edma       hs_mmcsd           usb_dev_bulk          watchdogTimer
enet_echo  irq_preemption     usb_dev_comp_ser_ser
enet_lwip  neonVFPBenchmark   usb_device_host_msc





################################################################################
Nov8 -2016:

ls -l /sys/kernel/debug/usb/
jaguar-ThinkPad-T540p usb # ls
devices  ehci  ohci  uhci uvcvideo

jaguar-ThinkPad-T540p usb # modprobe usbmon

jaguar-ThinkPad-T540p usb # ls
devices  ehci  ohci  uhci  usbmon  uvcvideo
jaguar-ThinkPad-T540p usb # cd usbmon

jaguar-ThinkPad-T540p usbmon # ls
0s  0u  1s  1t  1u  2s  2t  2u  3s  3t  3u  4s  4t  4u
jaguar-ThinkPad-T540p usbmon # 


launch wireshark :
   select usbmon1 interface to monitor.
   
   jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 015: ID 1fc9:0009 NXP Semiconductors 
Bus 001 Device 017: ID 1ff9:0520                      ================>
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

ALIGNED(4) const uint8_t USB_DeviceDescriptor[] = {
	USB_DEVICE_DESC_SIZE,			/* bLength */
 ......
	WBVAL(0x1FF9),					/* idVendor */           //
	WBVAL(0x0520),					/* idProduct */
	WBVAL(0x0100),					/* bcdDevice */
 ......
};


jaguar@jaguar-ThinkPad-T540p ~ $ lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M
    |__ Port 2: Dev 17, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 3: Dev 15, If 0, Class=Vendor Specific Class, Driver=usbfs, 480M
    |__ Port 7: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
    |__ Port 12: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
    |__ Port 12: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M





   jaguar@jaguar-ThinkPad-T540p ~ $ ls /sys/bus/usb/devices/
1-0:1.0  1-12:1.0  1-2      1-3      1-7      2-0:1.0  3-1      4-0:1.0  4-1:1.0  usb2  usb4
1-12     1-12:1.1  1-2:1.0  1-3:1.0  1-7:1.0  3-0:1.0  3-1:1.0  4-1      usb1     usb3
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls /sys/bus/usb/drivers
btusb  hub  usb  usbfs  uvcvideo
jaguar@jaguar-ThinkPad-T540p ~ $ 
jaguar@jaguar-ThinkPad-T540p ~ $ ls -l /sys/bus/usb/devices/
total 0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-0:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-12 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-12:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-12:1.1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-12/1-12:1.1
lrwxrwxrwx 1 root root 0 Nov  8 19:58 1-2 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-2
lrwxrwxrwx 1 root root 0 Nov  8 19:58 1-2:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2:1.0
lrwxrwxrwx 1 root root 0 Nov  8 19:57 1-3 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-3
lrwxrwxrwx 1 root root 0 Nov  8 19:57 1-3:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-7 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7
lrwxrwxrwx 1 root root 0 Nov  8 18:56 1-7:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 2-0:1.0 -> ../../../devices/pci0000:00/0000:00:14.0/usb2/2-0:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 3-0:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-0:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 3-1 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1
lrwxrwxrwx 1 root root 0 Nov  8 18:56 3-1:1.0 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 4-0:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-0:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 4-1 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1
lrwxrwxrwx 1 root root 0 Nov  8 18:56 4-1:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1:1.0
lrwxrwxrwx 1 root root 0 Nov  8 18:56 usb1 -> ../../../devices/pci0000:00/0000:00:14.0/usb1
lrwxrwxrwx 1 root root 0 Nov  8 18:56 usb2 -> ../../../devices/pci0000:00/0000:00:14.0/usb2
lrwxrwxrwx 1 root root 0 Nov  8 18:56 usb3 -> ../../../devices/pci0000:00/0000:00:1a.0/usb3
lrwxrwxrwx 1 root root 0 Nov  8 18:56 usb4 -> ../../../devices/pci0000:00/0000:00:1d.0/usb4


jaguar@jaguar-ThinkPad-T540p ~ $ ls -l /sys/bus/usb/drivers
total 0
drwxr-xr-x 2 root root 0 Nov  8 18:56 btusb
drwxr-xr-x 2 root root 0 Nov  8 20:02 hub
drwxr-xr-x 2 root root 0 Nov  8 20:02 usb
drwxr-xr-x 2 root root 0 Nov  8 20:02 usbfs
drwxr-xr-x 2 root root 0 Nov  8 18:56 uvcvideo


   

nxpUSBlib source code Analysis:
=========================================

Example_GenericHIDDevice/GenericHID.c
main==>SetupHardware ==>USB_Init



vi LPCUSBlib/Drivers/USB/Core/LPC/USBController_LPC.c +46
USB_Init --> USB_Memory_Init,HAL_USBInit,USB_ResetInterface
USB_ResetInterface ==> USB_Init_Device or USB_Init_Host  (USB_CAN_BE_DEVICE / USB_CAN_BE_HOST)
USB_Init_Device ==> UsbdRom_Init or Endpoint_ConfigureEndpoint (USB_DEVICE_ROM_DRIVER / no rom driver)

































##########################
Analyse below:jaguar-ThinkPad-T540p usbmon # cat 1u

URBTag
Timestamp
EventType
Address-word: URBtype,direction,Busnumber,Deviceaddress,Endpointnumber
Status-word : URBstatus,[interval],[startframe],[errorcount]

ffff8801f6e18300 1935003616 C Ii:1:001:1 0:2048 2 = 4000
callback Interrupt IN bus-1 deviceaddr-001 endpoint-1  


ffff8801f6e18300 1935003632 S Ii:1:001:1 -115:2048 4 <

ffff8801ff256600 1935003647 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935003661 C Ci:1:001:0 0 4 = 01010100


ffff8801ff256600 1935003665 S Co:1:001:0 s 23 01 0010 0006 0000 0
ffff8801ff256600 1935003675 C Co:1:001:0 0 0


ffff8801ff256600 1935003679 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935003687 C Ci:1:001:0 0 4 = 01010000
ffff8801ff256600 1935035691 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935035706 C Ci:1:001:0 0 4 = 01010000
ffff8801ff256600 1935067684 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935067720 C Ci:1:001:0 0 4 = 01010000
ffff8801ff256600 1935099711 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935099731 C Ci:1:001:0 0 4 = 01010000
ffff8801ff256600 1935131728 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935131747 C Ci:1:001:0 0 4 = 01010000
ffff8801ff256600 1935131802 S Co:1:001:0 s 23 03 0004 0006 0000 0
ffff8801ff256600 1935131818 C Co:1:001:0 0 0
ffff8801ff256600 1935187700 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935187716 C Ci:1:001:0 0 4 = 03011000
ffff8801ff256600 1935187719 S Co:1:001:0 s 23 01 0014 0006 0000 0
ffff8801ff256600 1935187729 C Co:1:001:0 0 0
ffff8801ff256600 1935243758 S Ci:1:000:0 s 80 06 0100 0000 0040 64 <
ffff8801ff256600 1935243859 C Ci:1:000:0 0 18 = 12011001 ff000040 f91f2005 01000102 0301
ffff8801ff256600 1935243874 S Co:1:001:0 s 23 03 0004 0006 0000 0
ffff8801ff256600 1935243886 C Co:1:001:0 0 0
ffff8801ff256600 1935299702 S Ci:1:001:0 s a3 00 0000 0006 0004 4 <
ffff8801ff256600 1935299719 C Ci:1:001:0 0 4 = 03011000
ffff8801ff256600 1935299723 S Co:1:001:0 s 23 01 0014 0006 0000 0
ffff8801ff256600 1935299732 C Co:1:001:0 0 0
ffff8801ff256600 1935371726 S Ci:1:016:0 s 80 06 0100 0000 0012 18 <
ffff8801ff256600 1935371851 C Ci:1:016:0 0 18 = 12011001 ff000040 f91f2005 01000102 0301
ffff8801ff256600 1935371870 S Ci:1:016:0 s 80 06 0200 0000 0009 9 <
ffff8801ff256600 1935371995 C Ci:1:016:0 0 9 = 09022700 010100c0 32
ffff8801ff256600 1935372004 S Ci:1:016:0 s 80 06 0200 0000 0027 39 <
ffff8801ff256600 1935372177 C Ci:1:016:0 0 39 = 09022700 010100c0 32090400 0002ff00 00000000 00000000 00070582 02080001
ffff8801ff256000 1935372195 S Ci:1:016:0 s 80 06 0300 0000 00ff 255 <
ffff8801ff256000 1935372307 C Ci:1:016:0 0 4 = 04030904
ffff8801ff256000 1935372316 S Ci:1:016:0 s 80 06 0302 0409 00ff 255 <
ffff8801ff256000 1935372480 C Ci:1:016:0 0 30 = 1e034c00 50004300 55005300 42006c00 69006200 20003100 37003600 3800
ffff8801ff256000 1935372497 S Ci:1:016:0 s 80 06 0301 0409 00ff 255 <
ffff8801ff256000 1935372603 C Ci:1:016:0 0 16 = 10034e00 47005800 50004e00 58005000
ffff8801ff256000 1935372636 S Ci:1:016:0 s 80 06 0303 0409 00ff 255 <
ffff8801ff256000 1935372794 C Ci:1:016:0 0 30 = 10034100 42004300 44003100 32003300 40000010 0c034300 55005300 5400
ffff8801ff256540 1935372920 S Co:1:016:0 s 00 09 0001 0000 0000 0
ffff8801ff256540 1935373010 C Co:1:016:0 0 0
jaguar@jaguar-ThinkPad-T540p ~ $ dmesg
[  828.649069] usb 1-6: new full-speed USB device number 16 using xhci_hcd
[  828.777678] usb 1-6: config 1 has an invalid descriptor of length 0, skipping remainder of the config
[  828.777682] usb 1-6: config 1 interface 0 altsetting 0 has 0 endpoint descriptors, different from the interface descriptor's value: 2
[  828.778295] usb 1-6: New USB device found, idVendor=1ff9, idProduct=0520
[  828.778298] usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  828.778300] usb 1-6: Product: LPCUSBlib 1768
[  828.778301] usb 1-6: Manufacturer: NGXPNXP
[  828.778302] usb 1-6: SerialNumber: ABCD123
jaguar@jaguar-ThinkPad-T540p ~ $ 

jaguar@jaguar-ThinkPad-T540p ~ $ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp. 
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 138a:0017 Validity Sensors, Inc. 
Bus 001 Device 016: ID 1ff9:0520  
Bus 001 Device 004: ID 5986:026a Acer, Inc 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub