Re: [PATCH] DMI: Decode and save OEM String information

["Shem Multinymous" <multinymous@gmail.com>]

Hi,

On 7/27/06, Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
> I always thought that ACPI was supposed to describe everything that
> (a) consumes resources or requires a driver and (b) is not enumerable
> by other hardware standards such as PCI.
>
> If that's true, isn't it a BIOS defect if this embedded controller isn't
> described via ACPI?

The ThinkPad ACPI tables do list the relevant IO ports (0x1600-0x161F)
as reserved, but provide no way to discern what's behind them. Other
machines have different hardware on the same ports.

BTW, I should clarify that this embedded controller interface (used by
hdaps and tp_smapi) is different than the standard ACPI EC interface,
and goes through different IO ports.


> it seems like the ideal way forward
> would be to get the BIOS fixed so you could claim the device with PNP
> for future ThinkPads, and the table of OEM strings would not require
> ongoing maintenance.

This is unrealistic. The hdaps and tp_smapi drivers support dozens of
ThinkPad models, each with a different BIOS.

For the tp_smapi driver, AFAIK the only completely safe alternative to
this patch is a frequently-updated whitelist of over a hundred models,
identified by the existing DMI attributes.

  Shem