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62 lines
2.0 KiB
62 lines
2.0 KiB
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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