Re: New proposed DRM interface design

[Jesse Barnes <jbarnes@engr.sgi.com>]

On Sunday, September 5, 2004 8:31 am, Alan Cox wrote:
> The only glue structure you need for most of this is
>
> struct fb_device
> {
>  struct fb_info *fb; /* NULL or frame buffer device */
>  struct dri_whatever *dri;  /* As yet not nicely extracted DRI
>      object */
>  atomic_t refcnt;
>  void *private
> };
>
> Right now the drvdata for most PCI/AGP frame buffers is set to the
> fb_info. If that is set to the shared object then you can attach DRI and
> or FB first and they can find and call each others methods.
>
> It might also need a single lock just to avoid DRI deciding to go away
> while fb is calling dri and the reverse although I think the refcnt is
> easier and cheaper.
>
> With that in place if X tells DRI "640x480 starting here" then DRI can
> tell fb "640x480 starting here". Similarly fb and dri can find each
> other for acceleration and the kernel can become a DRI client for
> console acceleration.
>
> Once you have this object you can start attaching memory managers and
> mode setup pointers to the shared structure so that they live
> independantly.

So then this structure would represent a merged driver?  That is, you'd have a 
driver that attaches to display devices and creates this structure to manage 
fb and dri?

Jesse