在《debian下使用dynamic printk分析usb转串口驱动执行流程》中使用了usb转串口，当前例子使用usb网卡分析驱动（dm9601芯片)。
仍然需要使能dynamic printk,可以参考《debian下配置dynamic printk以及重新编译内核》配置并重新编译内核。
此处使用的usb网卡是从京东购买的沐阳 Jp1081。
未插入usb网卡时，查看usb信息：
$ lsusb Bus 001 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 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 002: ID 174f:114f Syntek Bus 003 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 004 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 003 Device 003: ID 105b:e065 Bus 003 Device 004: ID 0bda:0129 Realtek Semiconductor Corp.
插入usb网卡，查看usb信息：
$ lsusb Bus 001 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 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 002: ID 174f:114f Syntek Bus 003 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 004 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 003 Device 003: ID 105b:e065 Bus 003 Device 004: ID 0bda:0129 Realtek Semiconductor Corp. Bus 001 Device 074: ID 0fe6:9700 Kontron (Industrial Computer Source / ICS Advent) DM9601 Fast Ethernet Adapter
可以看到多出一行输出信息，其核心芯片是DM9601。
查看dm9601驱动信息：
$ sudo modinfo dm9601 [sudo] password for host: filename: /lib/modules/3.2.57/kernel/drivers/net/usb/dm9601.ko license: GPL description: Davicom DM9601 USB 1.1 ethernet devices author: Peter Korsgaard <jacmet@sunsite.dk> alias: usb:v0A46p9000d*dc*dsc*dp*ic*isc*ip* alias: usb:v0FE6p9700d*dc*dsc*dp*ic*isc*ip* alias: usb:v0FE6p8101d*dc*dsc*dp*ic*isc*ip* alias: usb:v0A47p9601d*dc*dsc*dp*ic*isc*ip* alias: usb:v0A46p8515d*dc*dsc*dp*ic*isc*ip* alias: usb:v0A46p0268d*dc*dsc*dp*ic*isc*ip* alias: usb:v0A46p6688d*dc*dsc*dp*ic*isc*ip* alias: usb:v0A46p9601d*dc*dsc*dp*ic*isc*ip* alias: usb:v07AAp9601d*dc*dsc*dp*ic*isc*ip* depends: usbnet,usbcore,mii intree: Y vermagic: 3.2.57 SMP mod_unload modversions
其中depends：一行后面的内容表示dm9601依赖于usbnet和usbcore和mii这三个驱动模块，
可以继续用modinfo查看其他模块的依赖关系，还有usbcore依赖于usb-common模块。
所以dm9601芯片依赖于dm9601、usbnet、mii、usbcore和usb-common这五个驱动程序。
查看drivers/net/usbMakefile,可以知道：
dm9601驱动由drivers/net/usb/dm9601.c生成的
usbnet驱动是由drivers/net/usb/usbnet.c生成的。
查看drivers/net/Makefile,可以知道：
mii驱动是由drivers/net/mii.c生成的。
查看drivers/usb/Makefile，可以知道：
usb-common驱动是由drivers/usb/usb-common.c生成的。
查看drivers/usb/core/Makefile，可以知道：
usbcore是由由drivers/usb/core/下面的usb.c hub.c hcd.c urb.c message.c driver.c config.c file.c buffer.c sysfs.c endpoint.c devio.c
notify.c generic.c quirks.c devices.c hcd-pci.c inode.c这些文件生成的。
编译一个配置脚本来配置dynamic printk，内容如下：
#!/bin/sh DYNAMIC_CONTROL=/sys/kernel/debug/dynamic_debug/control #usbcore echo 'file drivers/usb/core/usb.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/hub.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/hcd.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/urb.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/message.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/driver.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/config.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/file.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/buffer.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/sysfs.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/endpoint.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/device.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/notify.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/generic.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/quirks.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/devices.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/hci-pci.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/usb/core/inode.c +flmpt' > $DYNAMIC_CONTROL #drivers/base files echo 'file drivers/base/core.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/sys.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/bus.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/dd.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/syscore.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/driver.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/class.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/platform.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/cpu.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/firmware.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/init.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/map.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/devres.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/attribute_container.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/transport_class.c +flmpt' > $DYNAMIC_CONTROL echo 'file drivers/base/topology.c +flmpt' > $DYNAMIC_CONTROL #usb-common echo 'file drivers/usb/usb-common.c +flmpt' > $DYNAMIC_CONTROL #mii echo 'file drivers/net/mii.c +flmpt' > $DYNAMIC_CONTROL #usbnet echo 'file drivers/net/usbnet.c +flmpt' > $DYNAMIC_CONTROL #dm9601 echo 'file drivers/net/dm9601.c +flmpt' > $DYNAMIC_CONTROL
切换到root账户：
su
下面命令都是使用root账户执行：
挂载debugfs:
mount -t debugfs none /sys/kernel/debug
拔掉usb网卡，删除dm9601、usbnet和mii驱动（usbcore和usb_common无法删除，也应该删除）：
# modprobe -r dm9601 usbnet mii
然后执行上面配置dynamic printk的脚本。
然后插入usb网卡，得到下面信息（使用dmesg)：
[38737.680241] [11477] usbcore:usb_remote_wakeup:2737: usb usb1: usb wakeup-resume [38737.680254] [11477] usbcore:hcd_bus_resume:2013: usb usb1: usb auto-resume [38737.693461] [11477] usbcore:hub_resume:2810: hub 1-0:1.0: hub_resume [38737.693488] [11477] usbcore:hub_activate:860: hub 1-0:1.0: port 2: status 0101 change 0001 [38737.693504] [11477] usbcore:hub_activate:860: hub 1-0:1.0: port 4: status 0507 change 0000 [38737.797310] [164] usbcore:hub_events:3592: hub 1-0:1.0: state 7 ports 4 chg 0004 evt 0000 [38737.797343] [164] usbcore:hub_port_connect_change:3330: hub 1-0:1.0: port 2, status 0101, change 0001, 12 Mb/s [38737.925150] [164] usbcore:hub_port_debounce:2899: hub 1-0:1.0: debounce: port 2: total 100ms stable 100ms status 0x101 [38738.036986] usb 1-2: new full-speed USB device number 78 using xhci_hcd [38738.053846] [164] usbcore:usb_get_langid:791: usb 1-2: default language 0x0409 [38738.054100] [164] usbcore:usb_new_device:1973: usb 1-2: udev 78, busnum 1, minor = 77 [38738.054108] usb 1-2: New USB device found, idVendor=0fe6, idProduct=9700 [38738.054112] usb 1-2: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [38738.054116] usb 1-2: Product: USB 2.0 10/100M Ethernet Adaptor [38738.054125] [164] core:device_add:973: device: '1-2': device_add [38738.054287] [164] bus:bus_add_device:502: bus: 'usb': add device 1-2 [38738.054364] [164] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2 with driver usb [38738.054375] [164] dd:really_probe:114: bus: 'usb': really_probe: probing driver usb with device 1-2 [38738.054395] [164] usbcore:usb_probe_device:228: usb 1-2: usb_probe_device [38738.054407] [164] usbcore:usb_choose_configuration:146: usb 1-2: configuration #1 chosen from 1 choice [38738.054669] [164] usbcore:usb_set_configuration:1863: usb 1-2: adding 1-2:1.0 (config #1, interface 0) [38738.054684] [164] core:device_add:973: device: '1-2:1.0': device_add [38738.054720] [164] bus:bus_add_device:502: bus: 'usb': add device 1-2:1.0 [38738.054802] [164] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2:1.0 with driver usbserial_generic [38738.054814] [164] dd:really_probe:114: bus: 'usb': really_probe: probing driver usbserial_generic with device 1-2:1.0 [38738.054837] [164] usbcore:usb_probe_interface:279: usbserial_generic 1-2:1.0: usb_probe_interface [38738.054851] [164] usbcore:usb_probe_interface:297: usbserial_generic 1-2:1.0: usb_probe_interface - got id [38738.054877] [164] dd:really_probe:152: usbserial_generic: probe of 1-2:1.0 rejects match -19 [38738.054916] [164] core:device_add:973: device: 'ep_81': device_add [38738.054975] [164] core:device_add:973: device: 'ep_02': device_add [38738.055022] [164] core:device_add:973: device: 'ep_83': device_add [38738.055079] [164] dd:driver_bound:41: driver: '1-2': driver_bound: bound to device 'usb' [38738.055088] [164] dd:really_probe:137: bus: 'usb': really_probe: bound device 1-2 to driver usb [38738.055101] [164] core:device_add:973: device: 'ep_00': device_add [38738.079351] [11786] bus:bus_add_driver:702: bus: 'usb': add driver dm9601 [38738.079374] [11786] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2:1.0 with driver dm9601 [38738.079382] [11786] dd:really_probe:114: bus: 'usb': really_probe: probing driver dm9601 with device 1-2:1.0 [38738.079392] [11786] usbcore:usb_probe_interface:279: dm9601 1-2:1.0: usb_probe_interface [38738.079399] [11786] usbcore:usb_probe_interface:297: dm9601 1-2:1.0: usb_probe_interface - got id [38738.092443] [11786] core:device_add:973: device: 'eth0': device_add [38738.093442] dm9601 1-2:1.0: eth0: register 'dm9601' at usb-0000:00:14.0-2, Davicom DM9601 USB Ethernet, 00:e0:4c:53:44:58 [38738.093482] [11786] dd:driver_bound:41: driver: '1-2:1.0': driver_bound: bound to device 'dm9601' [38738.093497] [11786] dd:really_probe:137: bus: 'usb': really_probe: bound device 1-2:1.0 to driver dm9601 [38738.093586] usbcore: registered new interface driver dm9601 [38738.101169] [11663] core:device_rename:1651: device: 'eth0': device_rename: renaming to 'eth1' [38738.137651] udevd[11663]: renamed network interface eth0 to eth1 [38738.188557] dm9601 1-2:1.0: eth1: link up, 100Mbps, full-duplex, lpa 0xFFFF [38748.657111] eth1: no IPv6 routers present
前面大部分输出信息跟使用usb转串口类似，都是使用usbcore检测设备信息以及设备驱动，最终检测到dm9601驱动
usb中有个remote wakeup功能,usb hcd(host controller driver)中默认remote wakeup功能就是调用hcd_resume_work实现，
该函数会调用usb_remote_wakeup,就产生了输出信息：
[38737.680241] [11477] usbcore:usb_remote_wakeup:2737: usb usb1: usb wakeup-resume
在usb子系统初始化之时，执行usb_init函数，该函数调用了usb_register_device_driver(&usb_generic_driver, THIS_MODULE).
默认情况下找到usb设备都是先调用usb_generic_driver的相关函数。此处执行resume功能就调用usb.generic_driver的resume功能，
即generic_resume函数。
在执行generic_resume时,调用了hcd_bus_resume函数，输出了下面信息：
[38737.680254] [11477] usbcore:hcd_bus_resume:2013: usb usb1: usb auto-resume
接着调用hub的resume功能，即hub_resume函数，输出下面信息：
[38737.693461] [11477] usbcore:hub_resume:2810: hub 1-0:1.0: hub_resume
hub_resume中还执行hub_activate(hub,HUB_RESUME),在hub_activate中检查每一个port是否状态发生了改变，并输出信息，
产生下面两行输出：
[38737.693488] [11477] usbcore:hub_activate:860: hub 1-0:1.0: port 2: status 0101 change 0001 [38737.693504] [11477] usbcore:hub_activate:860: hub 1-0:1.0: port 4: status 0507 change 0000
在usb hub初始化时，创建了一个内核线程(名为khubd)，线程执行函数是hub_thread.
在hub_thread函数中循环执行hub_events函数，hub_events中循环检测是否port状态发生了改变，并根据其改变状态执行功能。
hub_events函数中如果hub_event_list不空，那么就获取从hub_event_list获取对应的事件，根据该事件得到hub，再根据hub得到对应的hub_dev。
然后输出事件信息：
[38737.797310] [164] usbcore:hub_events:3592: hub 1-0:1.0: state 7 ports 4 chg 0004 evt 0000
hub_events中检测到port连接状态发生了改变，会调用hub_port_connect_change函数，该函数开头输出信息：
[38737.797343] [164] usbcore:hub_port_connect_change:3330: hub 1-0:1.0: port 2, status 0101, change 0001, 12 Mb/s
在hub_port_connect_change函数中执行hub_port_debounce函数，输出下面信息：
[38737.925150] [164] usbcore:hub_port_debounce:2899: hub 1-0:1.0: debounce: port 2: total 100ms stable 100ms status 0x101
接着执行hub_port_init函数，在hub_port_init中输出下面信息：
[38738.036986] usb 1-2: new full-speed USB device number 78 using xhci_hcd
接着执行usb_new_device函数，调用usb_enumerate_device函数，usb_enumerate_device调用usb_cache_string，
usb_cache_string调用usb_string,usb_string调用usb_get_langid，输出下面信息：
[38738.053846] [164] usbcore:usb_get_langid:791: usb 1-2: default language 0x0409
之后usb_new_device输出下面信息：
[38738.054100] [164] usbcore:usb_new_device:1973: usb 1-2: udev 78, busnum 1, minor = 77
在usb_new_device中调用announce_device函数，输出下面信息：
[38738.054108] usb 1-2: New USB device found, idVendor=0fe6, idProduct=9700 [38738.054112] usb 1-2: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [38738.054116] usb 1-2: Product: USB 2.0 10/100M Ethernet Adaptor
usb_new_device接着调用device_add。
在device_add中输出信息：
[38738.054125] [164] core:device_add:973: device: '1-2': device_add
device_add中接着调用bus_add_device。
bus_add_device中输出信息：
[38738.054287] [164] bus:bus_add_device:502: bus: 'usb': add device 1-2
device_add中接着调用bus_probe_device，bus_probe_device中执行device_attach.
在device_attach中对其bus上的每一个驱动都调用__device_attach函数。
在__device_attach中对调用driver_match_device来对驱动和设备来进行匹配，如果匹配成功，则调用driver_probe_device，否则直接返回0.
此处将设备和驱动匹配成功，所以执行driver_probe_device函数。
在执行driver_probe_device时输出下面信息：
[38738.054364] [164] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2 with driver usb
driver_probe_device继续执行really_probe函数，输出下面信息：
[38738.054375] [164] dd:really_probe:114: bus: 'usb': really_probe: probing driver usb with device 1-2
driver_probe_device会执行其驱动的probe函数。之前在对usb subsys初始化时调用了usb_init,usb_init调用了
usb_register_device_driver(&usb_generic_driver, THIS_MODULE)，然后usb_register_device_driver中设置了驱动的probe函数是usb_probe_device.
所以这里执行usb_probe_device函数，在此函数中输出下面信息：
[38738.054395] [164] usbcore:usb_probe_device:228: usb 1-2: usb_probe_device
usb_probe_device还会执行usb_device_driver的probe函数，而usb_generic_driver定义时就将其probe设置成了generic_probe.
所以这里会调用generic_probe函数。在generic_probe中会调用usb_choose_configuration，从而输出下面信息：
[38738.054407] [164] usbcore:usb_choose_configuration:146: usb 1-2: configuration #1 chosen from 1 choice
generic_probe中接下来调用usb_set_configuration.
usb_set_configuration中对usb接口输出下面信息：
[38738.054669] [164] usbcore:usb_set_configuration:1863: usb 1-2: adding 1-2:1.0 (config #1, interface 0)
在usb_set_configuration中调用device_add函数添加该usb接口设备。
device_add中输出下面信息：
[38738.054684] [164] core:device_add:973: device: '1-2:1.0': device_add
device_add中调用bus_add_device，输出下面信息：
[38738.054720] [164] bus:bus_add_device:502: bus: 'usb': add device 1-2:1.0
device_add接下来调用bus_probe_device,跟前面类似，仍然对总线上所有驱动和设备来进行匹配，如果匹配成功，
就执行这个驱动。此处匹配usbserial-generic驱动成功，执行driver_probe_device,输出下面信息：
[38738.054802] [164] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2:1.0 with driver usbserial_generic
driver_probe_device中调用really_probe，在really_probe中输出信息：
[38738.054814] [164] dd:really_probe:114: bus: 'usb': really_probe: probing driver usbserial_generic with device 1-2:1.0
跟前面类似，调用驱动的probe函数，即usb_probe_interface函数。
usb_probe_interface中输出下面信息：
[38738.054837] [164] usbcore:usb_probe_interface:279: usbserial_generic 1-2:1.0: usb_probe_interface [38738.054851] [164] usbcore:usb_probe_interface:297: usbserial_generic 1-2:1.0: usb_probe_interface - got id
该函数执行失败，在回到really_probe函数后输出下面信息：
[38738.054877] [164] dd:really_probe:152: usbserial_generic: probe of 1-2:1.0 rejects match -19
接下来三行输出信息不知道是哪部分代码产生的：
[38738.054916] [164] core:device_add:973: device: 'ep_81': device_add [38738.054975] [164] core:device_add:973: device: 'ep_02': device_add [38738.055022] [164] core:device_add:973: device: 'ep_83': device_add
此时返回到上一个执行的really_probe,执行driver_bound,输出信息：
[38738.055079] [164] dd:driver_bound:41: driver: '1-2': driver_bound: bound to device 'usb'
然后在really_probe中输出下面信息：
[38738.055079] [164] dd:driver_bound:41: driver: '1-2': driver_bound: bound to device 'usb'
下面一行输出信息页不知道是那部分代码产生的（可能和当前代码执行流程无关?)：
[38738.055101] [164] core:device_add:973: device: 'ep_00': device_add
接下来加载dm9601驱动，调用dm9601_init,dm9601_init调用usb_register(&dm9601_driver).
usb_register中调用bus_add_driver。
在bus_add_driver中输出下面信息：
[38738.079351] [11786] bus:bus_add_driver:702: bus: 'usb': add driver dm9601
bus_add_driver中调用driver_attach,driver_attach中对于总线上每个设备执行__driver_attach.
__driver_attach中对设备和驱动进行匹配，如果匹配成功，则执行driver_probe_device.
此处匹配成功，执行driver_probe_device函数，输出下面信息：
[38738.079374] [11786] dd:driver_probe_device:211: bus: 'usb': driver_probe_device: matched device 1-2:1.0 with driver dm9601
driver_probe_device中执行really_probe函数，然后调用驱动的probe函数，即usb_probe_interface函数，
usb_probe_interface中输出下面信息：
[38738.079392] [11786] usbcore:usb_probe_interface:279: dm9601 1-2:1.0: usb_probe_interface [38738.079399] [11786] usbcore:usb_probe_interface:297: dm9601 1-2:1.0: usb_probe_interface - got id
usb_probe_interface中调用driver->probe，dm9601_driver定义中其probe函数即usbnet_probe函数。
usbnet_probe函数中调用register_netdev,register_netdev调用register_netdevice,register_netdevice调用netdev_register_kobject，
netdev_register_kobject将设备名称设置成eth0,然后调用device_add,在device_add中输出下面信息：
[38738.092443] [11786] core:device_add:973: device: 'eth0': device_add
usbnet_probe继续执行，输出下面信息：
[38738.093442] dm9601 1-2:1.0: eth0: register 'dm9601' at usb-0000:00:14.0-2, Davicom DM9601 USB Ethernet, 00:e0:4c:53:44:58
回到really_probe继续执行，调用driver_bound,在driver_bound中输出下面信息：
[38738.093482] [11786] dd:driver_bound:41: driver: '1-2:1.0': driver_bound: bound to device 'dm9601'
然后在really_probe中输出下面信息：
[38738.093497] [11786] dd:really_probe:137: bus: 'usb': really_probe: bound device 1-2:1.0 to driver dm9601
回到前面的usb_register_driver，输出下面信息：
[38738.093586] usbcore: registered new interface driver dm9601
我的系统中udev规则（/etc/udev/rules.d/70-persistent-net.rules）中有下面内容：
# USB device 0x:0x (dm9601) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:e0:4c:53:44:58", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL== "eth*", NAME="eth1"
所以在添加usb网卡时会将eth0改成eth1，产生下面输出：
[38738.101169] [11663] core:device_rename:1651: device: 'eth0': device_rename: renaming to 'eth1' [38738.137651] udevd[11663]: renamed network interface eth0 to eth1
dm9601驱动还会调用dm9601_link_reset，dm9601_link_reset调用mii_check_media,mii_check_media中产生下面输出：
[38738.188557] dm9601 1-2:1.0: eth1: link up, 100Mbps, full-duplex, lpa 0xFFFF
最后一行信息是在addr_rs_timer函数中输出的，该函数被配置成ipv6接口的定时器函数，过一段时间都会调用该函数。
到这里整个usb网卡检测过程就完成了，其他的网卡相关函数还需要看看书后再来分析。