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diff --git a/Documentation/fb/internals.txt b/Documentation/fb/internals.txt deleted file mode 100644 index 9b2a2b2f3e57..000000000000 --- a/Documentation/fb/internals.txt +++ /dev/null @@ -1,82 +0,0 @@ - -This is a first start for some documentation about frame buffer device -internals. - -Geert Uytterhoeven <geert@linux-m68k.org>, 21 July 1998 -James Simmons <jsimmons@user.sf.net>, Nov 26 2002 - --------------------------------------------------------------------------------- - - *** STRUCTURES USED BY THE FRAME BUFFER DEVICE API *** - -The following structures play a role in the game of frame buffer devices. They -are defined in <linux/fb.h>. - -1. Outside the kernel (user space) - - - struct fb_fix_screeninfo - - Device independent unchangeable information about a frame buffer device and - a specific video mode. This can be obtained using the FBIOGET_FSCREENINFO - ioctl. - - - struct fb_var_screeninfo - - Device independent changeable information about a frame buffer device and a - specific video mode. This can be obtained using the FBIOGET_VSCREENINFO - ioctl, and updated with the FBIOPUT_VSCREENINFO ioctl. If you want to pan - the screen only, you can use the FBIOPAN_DISPLAY ioctl. - - - struct fb_cmap - - Device independent colormap information. You can get and set the colormap - using the FBIOGETCMAP and FBIOPUTCMAP ioctls. - - -2. Inside the kernel - - - struct fb_info - - Generic information, API and low level information about a specific frame - buffer device instance (slot number, board address, ...). - - - struct `par' - - Device dependent information that uniquely defines the video mode for this - particular piece of hardware. - - --------------------------------------------------------------------------------- - - *** VISUALS USED BY THE FRAME BUFFER DEVICE API *** - - -Monochrome (FB_VISUAL_MONO01 and FB_VISUAL_MONO10) -------------------------------------------------- -Each pixel is either black or white. - - -Pseudo color (FB_VISUAL_PSEUDOCOLOR and FB_VISUAL_STATIC_PSEUDOCOLOR) ---------------------------------------------------------------------- -The whole pixel value is fed through a programmable lookup table that has one -color (including red, green, and blue intensities) for each possible pixel -value, and that color is displayed. - - -True color (FB_VISUAL_TRUECOLOR) --------------------------------- -The pixel value is broken up into red, green, and blue fields. - - -Direct color (FB_VISUAL_DIRECTCOLOR) ------------------------------------- -The pixel value is broken up into red, green, and blue fields, each of which -are looked up in separate red, green, and blue lookup tables. - - -Grayscale displays ------------------- -Grayscale and static grayscale are special variants of pseudo color and static -pseudo color, where the red, green and blue components are always equal to -each other. - |