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			63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			ReStructuredText
		
	
	
	
	
	
| Frame Buffer Library
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| ====================
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| Frame Buffer Memory
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| -------------------
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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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| 
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| Frame Buffer Colormap
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| ---------------------
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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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| 
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| Frame Buffer Video Mode Database
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| --------------------------------
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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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| 
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| .. kernel-doc:: drivers/video/fbdev/core/modedb.c
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|    :export:
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| 
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| Frame Buffer Macintosh Video Mode Database
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| ------------------------------------------
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| 
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| .. kernel-doc:: drivers/video/fbdev/macmodes.c
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|    :export:
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| 
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| Frame Buffer Fonts
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| ------------------
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| 
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| Refer to the file lib/fonts/fonts.c for more information.
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| 
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