Re: [Linux-fbdev-devel] New API

[James S. <jsi...@tr...>]

> > Hi folks. I finally hammered a newer api for framebuffer devices. I
> > adapted skeletonfb.c to show it off. Feedback welcomed.
> 
> Good news!

A few drivers have been converted over to it :-) 


> >     /*
> >      *  If your driver supports multiple boards, you should make these
> >      *  arrays, or allocate them dynamically (using kmalloc()).
> >      */
> 
> Perhaps make it more clear that this applies to all 3 (4?) variables below

I should. In reality all of them can be dynamically allocated. 

> > /**
> >  *      xxxfb_check_var - REQUIRED function. Validates a var passed in.
> 
> Is this function really required? Imagine a graphics card with a fixed
> resolution (e.g. old Sun3 bwtwo), or vesafb/offb.
> 
> If it's NULL, you cannot change var, and upper layer can check that an
> identical var was passed (using memcmp()).

Wait. Your right. In CVS I made it optional. I missed updating this. If
you can change the mode it just returns the current mode instead.

        if (!info->fbops->fb_check_var) {
                *var = info->var;
                return 0;
        }

> >  *  	xxxfb_setcolreg - REQUIRED function. Sets a color register.
> 
> Is this function really required? Imagine static pseudocolor (fixed palette)
> hardware.

I never thought about that. Your right. Will fix. 

> >     /* Truecolor has hardware independent palette */
> >     if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
> >        u32 v;
> >
> >        if (regno >= 16)
> >            return 1;
> >
> >        v = (red << info->var.red.offset) |
> >            (green << info->var.green.offset) |
> >            (blue << info->var.blue.offset) |
> >            (transp << info->var.transp.offset);
> >        if (info->var.bits_per_pixel == 16)
> >            ((u16*)(info->pseudo_palette))[regno] = v;
> >        else
> >            ((u32*)(info->pseudo_palette))[regno] = v;
> >        return 0;
> 
> What about info->var.bits_per_pixel == 8? Some handhelds are RGB332 truecolor.

Your right again. Even the Matrox millenium could do this mode. I will add
as a example. Made changes to skeletonfb.c.