Linux内核裁剪入门实例分析—USB转网口驱动模块配置

太过爱你忘了你带给我的痛 2023-06-14 10:51 54阅读 0赞

最近在调试USB转网口，涉及到Linux内核编译配置文件的更改，记录一下调试过程。

首先需要了解USB设备接入后系统的识别信息，打印内核日志：

root@MyDevice:/# dmesg | tail -20
    [ 5364.325642] usb 1-1.1: new high-speed USB device number 5 using xhci-hcd
    [ 5364.426138] usb 1-1.1: New USB device found, idVendor=0bda, idProduct=8152
    [ 5364.426145] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
    [ 5364.426148] usb 1-1.1: Product: USB 10/100 LAN
    [ 5364.426152] usb 1-1.1: Manufacturer: Realtek
    [ 5364.426155] usb 1-1.1: SerialNumber: 00E04C3607A9

注意idProduct和Manufacturer内容，我用的这款USB转网口设备嵌入的是瑞昱的8152网口芯片。

进入Linux内核源码的kernel目录执行

make menuconfig

进入到图形化配置界面，依次键选\[Device Drivers -> Network device support -> USB Network Adapters\]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MDQxMDgz_size_16_color_FFFFFF_t_70][]

找到 Realtek RTL8152/RTL8153 Based USB Ethernet Adapters选项使能即可。

以上选项信息参考博文：[https://www.eefocus.com/toradex/blog/16-12/401923\_7db7d.html][https_www.eefocus.com_toradex_blog_16-12_401923_7db7d.html]

然而，编译出的内核版本验证未成功，进入menuconfig图形界面发现勾选已失效（无法正常保存勾选），因此在内核源码目录下寻找config文件进行手动更改配置项

.../configs/.../normal\_kernel.config

查看代码

...
    CONFIG_USB_NET_DRIVERS=y
    # CONFIG_USB_CATC is not set
    # CONFIG_USB_KAWETH is not set
    # CONFIG_USB_PEGASUS is not set
    #CONFIG_USB_RTL8150 is not set
    #CONFIG_USB_RTL8152 is not set
    # CONFIG_USB_LAN78XX is not set
    CONFIG_USB_USBNET=y
    CONFIG_USB_NET_AX8817X=y
    CONFIG_USB_NET_AX88179_178A=y
    CONFIG_USB_NET_CDCETHER=y
    # CONFIG_USB_NET_CDC_EEM is not set
    ...

将CONFIG\_USB\_RTL8150和CONFIG\_USB\_RTL8152设为使能，进入menuconfig查看相应配置项，已更新为勾选。

制作内核版本，烧写至设备后上电启动，dmesg查看USB接口信息：

[  471.409739] usb 1-1.1: new high-speed USB device number 4 using xhci-hcd
    [  471.510346] usb 1-1.1: New USB device found, idVendor=0bda, idProduct=8152
    [  471.510353] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
    [  471.510357] usb 1-1.1: Product: USB 10/100 LAN
    [  471.510360] usb 1-1.1: Manufacturer: Realtek
    [  471.510364] usb 1-1.1: SerialNumber: 00E04C3607A9
    [  471.701309] usb 1-1.1: reset high-speed USB device number 4 using xhci-hcd
    [  471.882926] r8152 1-1.1:1.0 eth1: v1.09.9

可以发现，多出了一行识别信息，r8152被识别为eth1（此时ifconfig发现新的网卡，但是没有IP等信息），使用udhcpc命令为eth1分配动态ip地址：

udhcpc -i eth1

ifconfig查看网络配置情况：

root@MyDevice:~# ifconfig
    eth0      Link encap:Ethernet  HWaddr 00:0D:0D:D6:B6:21
              inet6 addr: fe80::20d:dff:fed6:b621/64 Scope:Link
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:367 errors:0 dropped:0 overruns:0 frame:0
              TX packets:525 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:92887 (90.7 KiB)  TX bytes:74001 (72.2 KiB)
              Interrupt:30
    
    eth0.10   Link encap:Ethernet  HWaddr 00:0D:0D:D6:B6:21
              inet addr:10.16.7.122  Bcast:10.16.7.255  Mask:255.255.255.0
              inet6 addr: 2001:10:16:8::60/64 Scope:Global
              inet6 addr: fe80::20d:dff:fed6:b621/64 Scope:Link
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:0 errors:0 dropped:0 overruns:0 frame:0
              TX packets:97 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:0 (0.0 B)  TX bytes:18767 (18.3 KiB)
    
    eth1      Link encap:Ethernet  HWaddr 00:E0:4C:36:07:A9
              inet addr:192.168.1.101  Bcast:192.168.1.255  Mask:255.255.255.0
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:20 errors:0 dropped:0 overruns:0 frame:0
              TX packets:13 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:4679 (4.5 KiB)  TX bytes:2086 (2.0 KiB)
    
    lo        Link encap:Local Loopback
              inet addr:127.0.0.1  Mask:255.0.0.0
              inet6 addr: ::1/128 Scope:Host
              UP LOOPBACK RUNNING  MTU:65536  Metric:1
              RX packets:201 errors:0 dropped:0 overruns:0 frame:0
              TX packets:201 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:22516 (21.9 KiB)  TX bytes:22516 (21.9 KiB

发现eth1的IP地址生效，且与eth0.30在同一局域网，接着验证eth1的网络性能，发现无法ping通局域网中的其他设备。

route add default gw 192.168.1.1 eth1

进一步设置eth1的默认网关，再ping成功。t802:~\# route add default gw 192.168.1.1 eth1

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[https_www.eefocus.com_toradex_blog_16-12_401923_7db7d.html]: https://www.eefocus.com/toradex/blog/16-12/401923_7db7d.html