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DRM_GTF_MODE(9) DRM Core DRM_GTF_MODE(9)

NAME

drm_gtf_mode - create the modeline based on the GTF algorithm

SYNOPSIS

struct drm_display_mode * drm_gtf_mode(struct drm_device * dev, int hdisplay, int vdisplay, int vrefresh, bool interlaced, int margins);

ARGUMENTS

dev
drm device
hdisplay
hdisplay size
vdisplay
vdisplay size
vrefresh
vrefresh rate.
interlaced
whether to compute an interlaced mode
margins
desired margin (borders) size

DESCRIPTION

return the modeline based on GTF algorithm
This function is to create the modeline based on the GTF algorithm.

GENERALIZED TIMING FORMULA IS DERIVED FROM

GTF Spreadsheet by Andy Morrish (1/5/97)

AVAILABLE AT HTTP

//www.vesa.org
And it is copied from the file of xserver/hw/xfree86/modes/xf86gtf.c. What I have done is to translate it by using integer calculation. I also refer to the function of fb_get_mode in the file of drivers/video/fbmon.c

STANDARD GTF PARAMETERS

M = 600 C = 40 K = 128 J = 20

RETURNS

The modeline based on the GTF algorithm stored in a drm_display_mode object. The display mode object is allocated with drm_mode_create. Returns NULL when no mode could be allocated.

AUTHORS

Jesse Barnes <jesse.barnes@intel.com>
 
Intel Corporation,
Initial version
Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 
Ideas on board SPRL,
Driver internals
Daniel Vetter <daniel.vetter@ffwll.ch>
 
Intel Corporation,
Contributions all over the place

COPYRIGHT

May 2018 Kernel Hackers Manual 3.16