Android Qcom USB Driver学习(二)

usb hub区分端口 USB 子系统拓扑浅析
USB ID Database VendorID and ProductID

usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 4.19
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: xHCI Host Controller
usb usb1: Manufacturer: Linux 4.19.157 xhci-hcd
usb usb1: SerialNumber: xhci-hcd.0.auto
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected

usb 1-1: New USB device found, idVendor=0451, idProduct=8142, bcdDevice= 1.00
usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=1
usb 1-1: SerialNumber: 3E000079C0A6
hub 1-1:1.0: USB hub found
hub 1-1:1.0: 4 ports detected

usb 1-1.1: New USB device found, idVendor=0451, idProduct=8027, bcdDevice= 1.10
usb 1-1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=1
usb 1-1.1: SerialNumber: F30100617AAF
hub 1-1.1:1.0: USB hub found
hub 1-1.1:1.0: 2 ports detected

usb 1-1.2: New USB device found, idVendor=0424, idProduct=9e00, bcdDevice= 2.00
usb 1-1.2: Product: USB 2.0 Fast Ethernet Adapter

  usb1 是 USB Host Controller 直接控制的 roothub, roothub 是 1 起序的，所以这是第一个 hub；其中 “1-0:1.0”中的 “1-0”表示的是第 1 个 hub（即usb1）的第 0 号端口，但实际上 hub 的 port 编号是从 1 开始， 0 号 port 就是指 hub 自身。而 “:” 后面的 “1.0” 对应的语法格式是 “configID:interfaceID”，当检测到连在 roothub（usb1） 上的另一个新设备 “1-1”。 它连在 roothub 的第 2 个 port 上，编号从 1 开始。

idVendor(vid):    厂商ID
idProduct(pid):   产品ID
bcdDevice:        设备版本号

iManufacturer:    描述厂商的字符串索引
iProduct:         描述产品的字符串索引
iSerialNumber:    产品序列号字符串的索引

usb拓扑图

---------------------------------------+------------------------------  platform bus
			                           |
							   /-----------------
							   | Host Controller |  (usb1), which contains a roothub (1-0)
							   -----------------/  the roothub has only one downstream port
			                           |          
---------------------------------------+------------------------------ usb bus (level 1)
							           |		
							      /---------
							      |   1-1   |    hub (1-1), has 4 ports
							      ---------/
							           |
-----------------+----------------+---------------------+-------+----- usb bus (level 2)
                 |                |                     |       |
            /---------            |                     |       |
            |  1-1.1  | Fast Ethernet Adapter(1-1.2)  1-1.3   1.1.4     
            ---------/   
                 |
----------+-------------+------------------------------------------- usb bus (level 3)
          |             |
          |             |