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SubjectRe: 2.6.0-test1-ac1 Matrox Compile Error

> > Also doing this kind of thing only covers up broken framebuffer
> > drivers. Unfortunetly its going to take me months to cleanup and make the
> > fbdev drivers behave right.
>
> We don't have months. Should we be talking about reverting to the rather
> solid 2.4 framebuffer side for 2.6 in this case ?

Its not that the 2.5.X framebuffer layer is not solid. Except for the
software cursor it behaves right. The issue I have is the quality of the
framebuffer drivers. Lets take a example. In the new api we have two new
functions called check_var and set_par. Check_var's job is to test a
passed in mode to see if the hardware can support it. It is not to alter
or change any hardware states. The second function set_par does change the
hardware state. Lets look at the Mach64 driver. Mind you it does work and
functions. We have

static int atyfb_check_var(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct atyfb_par *par = (struct atyfb_par *) info->par;
struct crtc crtc;
union aty_pll pll;
int err;

if ((err = aty_var_to_crtc(info, var, &crtc)) ||
(err = par->pll_ops->var_to_pll(info, var->pixclock,
var->bits_per_pixel, &pll)))
return err;

#if 0 /* fbmon is not done. uncomment for 2.5.x -brad */
if (!fbmon_valid_timings(var->pixclock, htotal, vtotal, info))
return -EINVAL;
#endif
aty_crtc_to_var(&crtc, var);
var->pixclock = par->pll_ops->pll_to_var(info, &pll);
return 0;
}

We can see here that we first pass var into aty_var_to_crtc to generate a
crtc struct. Then at the end we do the reverse and use that crtc to create
a var. This is horribly done. Now lets look at what is in set_par.

if ((err = aty_var_to_crtc(info, var, &par->crtc)) ||
(err = par->pll_ops->var_to_pll(info, var->pixclock,
var->bits_per_pixel, &par->pll)))
return err;

Its being called twice. Once in check_var and again in set_par. Mind you
this works but the implementation is horribly done. I see this done alot
in various drivers. The reason it was done this way was because people
wanted a quick port to the new api without thinking much about it.

What makes me sad is I added accel hooks to speed up the console but I
don't see anyone using there accel engines. Everyone is just using my soft
accel functions :-( Using the soft accel was to be the exception not the
rule.


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