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63 lines
2.0 KiB
ReStructuredText
63 lines
2.0 KiB
ReStructuredText
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Frame Buffer Library
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====================
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The frame buffer drivers depend heavily on four data structures. These
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structures are declared in include/linux/fb.h. They are fb_info,
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fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs. The last
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three can be made available to and from userland.
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fb_info defines the current state of a particular video card. Inside
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fb_info, there exists a fb_ops structure which is a collection of
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needed functions to make fbdev and fbcon work. fb_info is only visible
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to the kernel.
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fb_var_screeninfo is used to describe the features of a video card
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that are user defined. With fb_var_screeninfo, things such as depth
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and the resolution may be defined.
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The next structure is fb_fix_screeninfo. This defines the properties
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of a card that are created when a mode is set and can't be changed
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otherwise. A good example of this is the start of the frame buffer
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memory. This "locks" the address of the frame buffer memory, so that it
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cannot be changed or moved.
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The last structure is fb_monospecs. In the old API, there was little
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importance for fb_monospecs. This allowed for forbidden things such as
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setting a mode of 800x600 on a fix frequency monitor. With the new API,
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fb_monospecs prevents such things, and if used correctly, can prevent a
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monitor from being cooked. fb_monospecs will not be useful until
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kernels 2.5.x.
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Frame Buffer Memory
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-------------------
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.. kernel-doc:: drivers/video/fbdev/core/fbmem.c
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:export:
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Frame Buffer Colormap
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---------------------
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.. kernel-doc:: drivers/video/fbdev/core/fbcmap.c
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:export:
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Frame Buffer Video Mode Database
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--------------------------------
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.. kernel-doc:: drivers/video/fbdev/core/modedb.c
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:internal:
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.. kernel-doc:: drivers/video/fbdev/core/modedb.c
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:export:
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Frame Buffer Macintosh Video Mode Database
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------------------------------------------
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.. kernel-doc:: drivers/video/fbdev/macmodes.c
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:export:
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Frame Buffer Fonts
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------------------
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Refer to the file lib/fonts/fonts.c for more information.
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