The Linux kernel timer uses a point-in-time timing method: starting at the current time and ending at a future time.
Kernel timer precision is not high
Kernel timer is not running periodically and will shut down automatically after timeout. You can turn on the timer again in the timer processing function.
Structures and functions
Posted on Fri, 05 Nov 2021 12:21:28 -0400 by OniLink
Blocking and non blocking are common access modes for Linux driver development. Programming should be considered. This introduction is blocked.
1, Blocking introduction
Blocking operation refers to suspending the process until the resource can be accessed when the device operation cannot obtain the device resource. The suspended operation ...
Posted on Thu, 04 Nov 2021 11:18:59 -0400 by skattabrain
The experiment in this chapter is modified from the code of "led driver of device tree" in Chapter 6, and the device tree does not need to be changed.
1, Atomic operation
Only one led can be operated at a time. When the driver is operating the led, other drivers cannot access the led. Idea: define an atomic shaping ...
Posted on Sun, 24 Oct 2021 15:50:57 -0400 by empnorton
1, Introduction to MISC driver
MISC driver is actually the simplest character device driver. The master device number of all MISC device drivers is 10. Different devices use different slave device numbers. MISC device will automatically create cdev, which does not need to be created manually as before. Therefore, using MISC device driver can s ...
Posted on Wed, 06 Oct 2021 20:44:43 -0400 by ratebuster
reference material: https://www.yuanzige.com/
I2C is a very common bus protocol. I2C is designed by NXP company. I2C uses two lines to count between the master controller and the slave According to the communication. One is SCL (serial clock line) and the other is SDA (serial data line). These two data lines need to be conn ...
Posted on Wed, 22 Sep 2021 13:34:18 -0400 by Ang3l0fDeath