M7101 - SMBus Support for ALi M15x3 based motherboards.

This module was written to enable SMBus support on ALi M15x3 chipset based
motherboards. Although it was written for and tested on Gigabytes GA-5AX 
it should work on any M15x3 chipset based board.

Probably most people trying this software on a GA-5AX will be utterly 
disappointed. We have seen no sensor chips on this board - only DIMMs
were connected to the SMBus. If you are trying to make lm_sensors read
temperature and voltage values you will be pretty lost.

CAVEAT: To perform it's task this module needs to manipulate PCI-config
data and device structures on a very low level. This bears the risk of 
causing havoc to your system in case anything goes wrong. Use this soft-
ware absolutely at your own risk.


Installation:
Untar the m7101.tgz file into an appropriate location and cd into the
m7101 subdirectory. Then type "make" to build the module file 'm7101.o'.
To insert it type 
	$ insmod m7101.o 
as root.

If everything goes well (no error messages) you will see a description like
the following when doing 'lspci -v':

00:03.0 Non-VGA unclassified device: Acer Laboratories Inc. [ALi] M7101 PMU
        Flags: medium devsel
        I/O ports at 4000
        I/O ports at 5000

and find an entry in the proc filesystem under /proc/bus/pci/00/03.0.


Removing the module removes the M7101 device from the proc file system
and switches the SMBus support off.

The lm_sensors software now should be able to access devices on the 
motherboard's SMBus through the M7101. 

Values for the ACPI-IO port (normally 0x4000) and the SMBus-IO port
(normally 0x5000) can be specified using the parameters acpi_io and 
smbus_io respectively on the insmod command line.

In case the module does not load you might want to switch on debugging
by uncommenting the second CFLAGS-line (with the -DM7101_DEBUG switch)
in the Makefile.

This module was written to activate SMBus support. I don't know neither
have I tested wether it works with the software from the ACPI project.

Note: Egcs compilers with versions below 2.95.2 do not compile properly.
Use either 2.95.2 or gcc 2.7.2.x.

I have tested this module with 2.2 kernels up to version 2.2.14.


I wish to thank Frank Bauer for his help with this module.

Burkhard Kohl (burkhard.kohl@gmx.de)