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author | Jonathan Corbet <corbet@lwn.net> | 2016-08-20 21:17:32 +0200 |
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committer | Jonathan Corbet <corbet@lwn.net> | 2016-08-22 22:42:08 +0200 |
commit | dcec3c8c9aea9e779c59f420465381c0f3322913 (patch) | |
tree | f8752c216e37a44941af6a16fda595c0fa4dde0d /Documentation/driver-api/frame-buffer.rst | |
parent | Docs: sphinxify device-drivers.tmpl (diff) | |
download | linux-dcec3c8c9aea9e779c59f420465381c0f3322913.tar.xz linux-dcec3c8c9aea9e779c59f420465381c0f3322913.zip |
docs: split up the driver book
We don't need to keep it as a single large file anymore; split it up so
that it is easier to manage and the individual sections can be read
directly as plain files.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/driver-api/frame-buffer.rst')
-rw-r--r-- | Documentation/driver-api/frame-buffer.rst | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/driver-api/frame-buffer.rst b/Documentation/driver-api/frame-buffer.rst new file mode 100644 index 000000000000..9dd3060f027d --- /dev/null +++ b/Documentation/driver-api/frame-buffer.rst @@ -0,0 +1,62 @@ +Frame Buffer Library +==================== + +The frame buffer drivers depend heavily on four data structures. These +structures are declared in include/linux/fb.h. They are fb_info, +fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs. The last +three can be made available to and from userland. + +fb_info defines the current state of a particular video card. Inside +fb_info, there exists a fb_ops structure which is a collection of +needed functions to make fbdev and fbcon work. fb_info is only visible +to the kernel. + +fb_var_screeninfo is used to describe the features of a video card +that are user defined. With fb_var_screeninfo, things such as depth +and the resolution may be defined. + +The next structure is fb_fix_screeninfo. This defines the properties +of a card that are created when a mode is set and can't be changed +otherwise. A good example of this is the start of the frame buffer +memory. This "locks" the address of the frame buffer memory, so that it +cannot be changed or moved. + +The last structure is fb_monospecs. In the old API, there was little +importance for fb_monospecs. This allowed for forbidden things such as +setting a mode of 800x600 on a fix frequency monitor. With the new API, +fb_monospecs prevents such things, and if used correctly, can prevent a +monitor from being cooked. fb_monospecs will not be useful until +kernels 2.5.x. + +Frame Buffer Memory +------------------- + +.. kernel-doc:: drivers/video/fbdev/core/fbmem.c + :export: + +Frame Buffer Colormap +--------------------- + +.. kernel-doc:: drivers/video/fbdev/core/fbcmap.c + :export: + +Frame Buffer Video Mode Database +-------------------------------- + +.. kernel-doc:: drivers/video/fbdev/core/modedb.c + :internal: + +.. kernel-doc:: drivers/video/fbdev/core/modedb.c + :export: + +Frame Buffer Macintosh Video Mode Database +------------------------------------------ + +.. kernel-doc:: drivers/video/fbdev/macmodes.c + :export: + +Frame Buffer Fonts +------------------ + +Refer to the file lib/fonts/fonts.c for more information. + |