adb Permission denied

adb 调试时出现权限不足

Administrator@aaron MINGW64 ~
$ adb shell
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
shell@firefly:/ $ cd sys/dvfs
cd sys/dvfs
shell@firefly:/sys/dvfs $ ls
ls
cpu_temp_enable
cpu_temp_target
dvfs_tree
shell@firefly:/sys/dvfs $ cat dvfs_tree
cat dvfs_tree
/system/bin/sh: cat: dvfs_tree: Permission denied

权限不足是因为没有获取 root 权限，需要先使用 adb root 获取 root 权限，再进 adb shell 。

Administrator@aaron MINGW64 ~
$ adb root
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
restarting adbd as root

Administrator@aaron MINGW64 ~
$ adb shell
root@firefly:/ # cd sys/dvfs
cd sys/dvfs
root@firefly:/sys/dvfs # ls
ls
cpu_temp_enable
cpu_temp_target
dvfs_tree
root@firefly:/sys/dvfs # cat dvfs_tree
cat dvfs_tree