Re: [ibm-acpi-devel] THINKPAD_ACPI_INPUT_ENABLED seems regressive

[Henrique de Moraes Holschuh <hmh@hmh.eng.br>]

On Wed, 01 Aug 2007, Hugh Dickins wrote:
> While I had CONFIG_THINKPAD_ACPI_INPUT_ENABLED=y and was trying
> to get Fn+F4 to give me Suspend to RAM somehow, I did try setting
> /sys/blah/blah/blah/hotkey_enable to 0.

That immediately tells the firmware to process hot keys at it would see fit.
You could call it "enter DOS mode for hot keys" if you want.

In that mode, it can and will do some stuff by itself, and Fn+F4 may
generate a sleep button event, for example.

The firmware can also report the hot key anyway, in which case
ibm-acpi/thinkpad-acpi lets it through.  I can probably filter off some, but
it would be unsafe to filter out the whole lot.

> That caused the Fn+F4 key to become active, except that it wanted
> to do Hibernation to Disk instead: a window popped up to tell me
> (IIRC) that my kernel command line didn't have a good resume=

Something in your user space reacted to the ACPI event the firmware
generates by default for FN+F4, and tried to do sleep-to-disk.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh