Add a driver for the ACPI-based EC event interface found on the OLPC
XO-1.5 laptop. This enables notification of battery/AC power events, and
enables various devices to be used as wakeup sources through regular ACPI
mechanisms.
This driver can't be built as a module, because some drivers need to know
at boot-time if SCI-based functionality is available via
olpc_ec_wakeup_available().
Signed-off-by: Daniel Drake <dsd@laptop.org> Acked-by: Andres Salomon <dilinger@queued.net> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>