Chapter 21. Framebuffer Drivers
Video cards always have a certain amount of RAM. This RAM is where the bitmap of image data is buffered for display. From the software point of view, the framebuffer is a character device providing access to this RAM.
That said, a framebuffer driver provides an interface for the following:
- The display mode setting
- Memory access to the video buffer
- Basic 2D acceleration operations (for example, scrolling)
To provide this interface, the framebuffer driver generally talks to the hardware directly. There are well-known framebuffer drivers, such as:
- intelfb: A framebuffer for various Intel 8xx/9xx compatible graphic devices
- vesafb: A framebuffer driver that uses the VESA standard interface to talk to the video hardware
- mxcfb: A framebuffer driver for the i.MX6 chip series
Framebuffer drivers are the simplest form of graphics drivers under Linux. They should not be confused with X.org drivers, which implement advanced features, such as 3D acceleration, or Kernel mode setting...
