Bug 49116

While the ACPI module is loaded the Kernel fails to detect the psm0 device.

This is the dmesg output while acpi_module is loaded:
Note the wrong allocation of the keyboard controller to the acpi bus!

atkbdc0: <Keyboard controller (i8042)> port 0x64,0x60 irq 1 on acpi0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
atkbd: the current kbd controller command byte 0047
atkbd: keyboard ID 0x54ab (2)
kbd0 at atkbd0
kbd0: atkbd0, AT 101/102 (2), config:0x1, flags:0x3d0000
psm0: unable to allocate IRQ

When I disable the loading of the acpi module the keyboard controller is
correctly attached to the isa0 bus. And most importandtly the psm0 device
is detected correctly.

atkbdc0: <Keyboard controller (i8042)> at port 0x64,0x60 on isa0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
atkbd: the current kbd controller command byte 0047
atkbd: keyboard ID 0x54ab (2)
kbd0 at atkbd0
kbd0: atkbd0, AT 101/102 (2), config:0x1, flags:0x3d0000
psm0: current command byte:0047
psm0: <PS/2 Mouse> irq 12 on atkbdc0
psm0: model Generic PS/2 mouse, device ID 0-00, 2 buttons
psm0: config:00000000, flags:00000000, packet size:3
psm0: syncmask:c0, syncbits:00

Fix: 

Disable acpi support.
How-To-Repeat: Just boot with and without the acpi module loaded