RE: 2.6.22-rc: regression: no irda0 interface (2.6.21 was OK), smsc does not find chip

[Linus Walleij (LD/EAB)]

Björn wrote:

> Something's wrong with this strategy.  The BIOS is telling us 
> that an SMCf010 device is present, active, and responds at io 
> ports 0x100-0x107 and 0x2e8-0x2ef.  The fact that it happens 
> to be on the other side of an ISA or LPC bridge should be 
> immaterial to the OS driver.

Yes, ideally. Yes of course it is wrong, or from a platonic
perspective. If nobody wrote buggy BIOS:es there would be no
problem.

There is some history in the preconfigure functions:
these come from the smcinit tool (see http://irda.sourceforge.net/smcinit/),
the hacks target laptops where the (buggy) BIOS does not properly
preconfigure the bridge. The assumption in the current code
is that Toshiba laptops with this smscchip will have the problem,
because they always had in the past...

I have no idea how bridges on such laptops are really preconfigured,
possibly with some special hacks to the (manufacturer-supplied-assumed)
"driver CD" for Windows only that apply some low-level tweaks to the
WinNT/XP boot process. All info an reverse-engineering on this subject
is warmly welcomed.

There are some troubles further related to issues due to laptops
supporting both ACPI and APM too I think, never dug into it.

Linus
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