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1Frame Buffer Library2====================3 4The frame buffer drivers depend heavily on four data structures. These5structures are declared in include/linux/fb.h. They are fb_info,6fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs. The last7three can be made available to and from userland.8 9fb_info defines the current state of a particular video card. Inside10fb_info, there exists a fb_ops structure which is a collection of11needed functions to make fbdev and fbcon work. fb_info is only visible12to the kernel.13 14fb_var_screeninfo is used to describe the features of a video card15that are user defined. With fb_var_screeninfo, things such as depth16and the resolution may be defined.17 18The next structure is fb_fix_screeninfo. This defines the properties19of a card that are created when a mode is set and can't be changed20otherwise. A good example of this is the start of the frame buffer21memory. This "locks" the address of the frame buffer memory, so that it22cannot be changed or moved.23 24The last structure is fb_monospecs. In the old API, there was little25importance for fb_monospecs. This allowed for forbidden things such as26setting a mode of 800x600 on a fix frequency monitor. With the new API,27fb_monospecs prevents such things, and if used correctly, can prevent a28monitor from being cooked. fb_monospecs will not be useful until29kernels 2.5.x.30 31Frame Buffer Memory32-------------------33 34.. kernel-doc:: drivers/video/fbdev/core/fbmem.c35 :export:36 37Frame Buffer Colormap38---------------------39 40.. kernel-doc:: drivers/video/fbdev/core/fbcmap.c41 :export:42 43Frame Buffer Video Mode Database44--------------------------------45 46.. kernel-doc:: drivers/video/fbdev/core/modedb.c47 :internal:48 49.. kernel-doc:: drivers/video/fbdev/core/modedb.c50 :export:51 52Frame Buffer Macintosh Video Mode Database53------------------------------------------54 55.. kernel-doc:: drivers/video/fbdev/macmodes.c56 :export:57 58Frame Buffer Fonts59------------------60 61Refer to the file lib/fonts/fonts.c for more information.62 63