platform | Kernel version | Android version |
---|---|---|
RK3399 | Linux4.4 | Android7.1 |
1. Introduction to mdev
Linux
Using traditional methods to create static equipment, in dev/
case created a large number of nodes, regardless of these nodes corresponding hardware device is present. Linux 2.6
The kernel was introduced to be executable in user space udev
, allowing users to no longer need to care about the major and minor device numbers. hotplug
Only when the system detects the device's hot plug ( ) event can the /dev
corresponding device node files be dynamically created and deleted. In short, udev
the main function is to create and delete device nodes in real time. If you want to be like Windows
systems, the system is able to recognize the device and mounted automatically when the device is plugged in, you can create the user space udev
rules and write a script file to achieve. mdev
Is actually embedded application development, udev
simplified version, its role and udev
the same, ie hot-swap event occurs or when the system starts, automatically generated files node drivers needed