ACPI: ibm-acpi: fix and extend fan control functions
This patch extend fan control functions, implementing enable/disable for
all write access modes, implementing level control for all level-capable
write access modes.
The patch also updates the documentation, explaining levels auto and
disengaged.
ABI changes:
1. Support level 0 as an equivalent to disable
2. Add support for level auto and level disengaged when doing
EC 0x2f fan control
3. Support enable/disable for all level-based write access modes
4. Add support for level command on FANS thinkpads, as per
thinkwiki reports
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
projects / linux-2.6 / commit