The patch below adds power management support to the i2c bus.
It adds just two small functions which call down to the devices
power management functions if they are present, so the i2c device
drivers will receive the suspend and resume events.

From: Gerd Knorr <kraxel@bytesex.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>