Framebuffer application programming practice of Linux Driver Development (i)

1. Framebuffer application Programming

(1) Open the device file

(2) Obtaining device information

Macro-defined commands in/linux/fb.h

Immutable information Fscreeninfo, using the IOCTL parameter has a Fbioget_fscreeninfo macro name, indicating the use of the IOCTL from the driver to obtain the unchanging information of the LCD device

Variable information vscreeninfo, using the IOCTL parameter with the Fbioget_vscreeninfo macro name, indicates that the variable information of the LCD device is obtained from the driver with the IOCTL

FB's driver framework divides all hardware information on the screen into two categories, one of which is immutable and cannot be changed by software (such as screen size, length, etc.). One type can be changed, for example, the resolution can be changed.

Two structures are defined in the kernel to represent variable and immutable information for LCD devices, as well as in/include/linux/fb.h

This article from "Whylinux" blog, declined reprint!

Framebuffer application programming practice of Linux Driver Development (i)