Re: i801_smbus: ... you should use it instead of the native driver

[Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>]

Dobry den Martine,

Sorry for the late reply.

On Mon, 26 Mar 2012 17:06:05 +0200, Martin Mokrejs wrote:
> Hi,
>   I have the following message logged through syslog on a 2.6.32.59 kernel:
> 
> Mar 26 11:21:55 vostro kernel: i801_smbus 0000:00:1f.3: PCI INT C -> GSI 18 (level, low) -> IRQ 18
> Mar 26 11:21:55 vostro kernel: ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver
> 
> 
> And here the relevant line from lspci:
> 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05)
> 
> 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05)
>         Subsystem: Dell Device 04b3
>         Flags: medium devsel, IRQ 18
>         Memory at f7f05000 (64-bit, non-prefetchable) [size=256]
>         I/O ports at f040 [size=32]
>         Kernel modules: i2c-i801
> 
> 
>   So what driver should I use instead? This is a Dell Vostro 3550 laptop with Core i7 on
> a SandyBridge.

Unfortunately, in most cases there's nothing that can be done. The ACPI
BIOS has requested the SMBus controller for its own use. You can
disassemble your DSDT to see if it has good reasons for that.
Unfortunately most BIOSes that do this don't bother implementing a
standard ACPI interface to the SMBus controller for the operating
system's benefit. We have drivers for these standards (i2c-scmi and
sbshc), but it only helps on the rare machines which implement them.

So, as a summary, if your ACPI BIOS implements any device in ACPI0001,
ACPI0005 or SMBUS01, you may get SMBus to work, otherwise you won't,
sorry. Feel free to bring up the issue to your hardware vendor if this
bothers you.

-- 
Jean Delvare