Re: [Linux-fbdev-devel] problem with gen_update_var

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

> In ywrap_up in fbcon.c, it has this code:
>
>     p->var.xoffset = 0;
>     p->var.yoffset = p->yscroll*fontheight(p);
>     p->var.vmode |= FB_VMODE_YWRAP;
>     p->fb_info->updatevar(unit, p->fb_info);
>
> (*p is struct display).  gen_update_var will call pan_display(info->var,
> con, info).

Only if con == currcon.

> But as can be seen, info->var is not updated by ywrap_up.

Your right. I will fix that.

> Unless, the low-level driver's implementation is to get the offsets
> from fb_display[con].var, that's the only time it will work.  But it
> will break userland apps that will call pan_display(var, con, info)
> expecting that the offsets contained in the passed var parameter will be
> updated.

Don't worry about userland apps. They can't pan non foreground consoles.
Only fbcon inside the kernel can.