The document focuses mainly on PCI soundcards. In the case of other device types, the API might be different, too. This document targets people who already have enough C language skills and have basic linux kernel programming knowledge. If you are already familiar with the older ALSA ver.
networking - How to write a dummy network device driver - Stack Overflow
Last month I talked about how to write a device driver for radio-tuner cards. This month, I'll cover video-capture devices, which share the same interfaces as radio devices. In order to explain the video-capture interface I will use the example of a camera that has no tuners or audio input. This keeps the example relatively clean.
Kernel space: the UIO interface for device drivers
In UNIX, hardware devices are accessed by the user through special device files. The device driver is a kernel component usually a module that interacts with a hardware device. In the UNIX world there are two categories of device files and thus device drivers: character and block. This division is done by the speed, volume and way of organizing the data to be transferred from the device to the system and vice versa.