Re: [PATCH] drm: exynos: Fix fb_videomode <-> drm_mode_modeinfo conversion

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi James,

On Thursday 08 March 2012 16:57:21 James Simmons wrote:
> > The fb_videomode structure stores the front porch and back porch in the
> > right_margin and left_margin fields respectively. right_margin should
> > thus be computed with hsync_start - hdisplay, and left_margin with
> > htotal - hsync_end. The same holds for the vertical direction.
> > 
> >        Active               Front           Sync            Back
> >        Region               Porch                           Porch
> > 
> > <-------------------><----------------><-------------><---------------->
> > 
> >   //////////////////|
> >  
> >  ////////////////// |
> > 
> > //////////////////  |..................               ..................
> > 
> >                                        _______________
> > 
> > <------ xres -------><- right_margin -><- hsync_len -><- left_margin -->
> > 
> > <---- hdisplay ----->
> > <------------ hsync_start ------------>
> > <--------------------- hsync_end -------------------->
> > <--------------------------------- htotal ----------------------------->
> > 
> > Fix the fb_videomode <-> drm_mode_modeinfo conversion functions
> > accordingly.
> 
> Wow I see this has remegered. Some time last year I posted a patch that
> had these routines in a generic format for people to use. I can repost
> them again if people are interested.

As part of the EDID parser rework, I will introduce a common structure to 
describe video modes. Conversion functions between the common structures and 
struct drm_mode_modeinfo, struct fb_videomode and struct v4l2_bt_timings will 
be provided. Direct conversion between drm_mode_modeinfo and fb_videomode 
should then disappear.

This being said, we could introduce add you conversion functions in the 
meantime. I will then post a patch to remove them when the common video mode 
structure will be pushed to mainline :-)

-- 
Regards,

Laurent Pinchart