背景
在 Linux-3.8 以后,Android 的内核分支,便去掉了 f_adb,改使用 USB function FS,在用户空间实现 USB adb 功能。这篇文章依据原作者的 Google+ 文章,在 Atmel sama5 开发板上做了測试,将步骤记录例如以下,供须要使用的读者參考,你也能够查看作者原文:https://plus.google.com/111524780435806926688/posts/AaEccFjKNHE
在 Linux-3.10 上使能 USB ADB
编译内核时使能 USB FunctionFS
When building your kernel, make sure to configure in FunctionFS:
Device Drivers -> USB Support -> USB Gadget Support
-> USB Gadget Driver -> Function Filesystem
Device Drivers -> USB Support -> USB Gadget Support
-> USB Gadget Driver -> Function Filesystem
设置正确的 USB vendor ID 和 Product ID
这个设置能够放在 bootcmd 或者载入内核模块的时候通过參数传递:
Modify your boot parameters to set the vendor and product ids so adb on your host recognizes the device.
g_ffs.idVendor=0x18d1 g_ffs.idProduct=0x4e26
g_ffs.idVendor=0x18d1 g_ffs.idProduct=0x4e26
Alternatively this can also be done if you built the gadget driver as a module at load time:
insmod g_ffs.ko idVendor=0x18d1 idProduct=0x4e26
启动 Android 并挂载 functionFS, 使能 USB adb
Now here I'm assuming you've got a serial port working. Boot your target device with your new kernel (and insmod the g_ffs driver if necessary), and setup the functionfs directory:
# mkdir /dev/usb-ffs
# mkdir /dev/usb-ffs/adb
# mount -o uid=2000,gid=2000 -t functionfs adb /dev/usb-ffs/adb
重新启动 adbd 守护进程
If everything is working, you can kill adbd and when it restarts it should find the functionfs mount and make use of it.
# ps adbd
# kill <pid for adbd>
然后进入 cmd 或者 Linux Host 就能够成功连接 usb adb 获得 Android shell 了
On your host system, connect to the target using the adb program:
$ ./adb shell
root@android:/#
Hooray there's your shell!