drm/mode: add the GTF algorithm in kernel space
Add the GTF algorithm in kernel space. And this function can be called to
generate the required modeline.
I copied it from the file of xserver/hw/xfree86/modes/xf86gtf.c. What I have
done is to translate it by using integer calculation. This is to avoid
the float-point calculation in kernel space.
At the same tie I also refer to the function of fb_get_mode in
drivers/video/fbmon.c
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 820bc09..125994d 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -739,4 +739,7 @@
extern struct drm_display_mode *drm_cvt_mode(struct drm_device *dev,
int hdisplay, int vdisplay, int vrefresh,
bool reduced, bool interlaced);
+extern struct drm_display_mode *drm_gtf_mode(struct drm_device *dev,
+ int hdisplay, int vdisplay, int vrefresh,
+ bool interlaced, int margins);
#endif /* __DRM_CRTC_H__ */