Re: [PATCH] Ignore ACPI video devices that aren't present in hardware

[Len Brown <lenb@kernel.org>]

On Saturday 26 January 2008 21:09, Matthew Garrett wrote:
> On Thu, Jan 24, 2008 at 05:21:17PM -0500, Len Brown wrote:
> > _ADR returns a bus-specific format.
> > In the case of a video device, section B.6.1 says that
> > _ADR returns a 32-bit device ID, and that
> 
> No, that's only true for the output devices - not the parent device. The 
> parent device is what's interesting here, and the format of its _ADR 
> method is not defined.

oh, ic, you're right.

> In practice, it's either going to be a PCI device ID or something 
> custom. If it's custom, it's unlikely to be a PCI device ID. From that 
> point of view, 0x10000 isn't magic - it's the lowest PCI device ID that 
> stands a real chance of being the graphics hardware or bridge that the 
> graphics hardware is attached to.

I share your uneasyness about this heuristic,
but I don't have a better idea
and this seems to work, so I think we should proceed...

But I have to agree with Thomas' feedback:
"I also wonder why you added this to acpi_video_bus_add_fs and not
 acpi_video_bus_add, but it's functionally the same."

or perhaps acpi_video_bus_check()?

I'll lob this into the test tree in the mean-time...

thanks,
-Len