On Wed, 05 Jul 2006, Vojtech Pavlik wrote: > > > I don't know about AMS, but talking to HDAPS when > > > you don't need to does waste enough system resources and power to actually > > > justify implementing this. > > I'd doubt any of the accelerometer implementations would consume much > power or CPU. It is not just CPU or power, although IMO striving for perfection on power management in a laptop is almost always a good thing if it can be done safely. HDAPS talks to the embedded controller using IO over the LPC bus, and not to the accelerometer chip or to a simple A/D i2c chip which is used excusively for accelerometer access. The EC interface for HDAPS data retrieval is not friendly to any errors, and hardlocks the machine somehow if any firmware bugs hit or if we violate any of the rules (that are not written anywhere) about how to access the EC without geting the SMBIOS unhappy. So, turning off HDAPS polling while it is not necessary really looks like a good idea overall. We are investigating the ACPI global lock as a way to at least get the SMBIOS to stay away from the EC while we talk to it, but we don't know if the entire SMBIOS firmware respects that lock. -- "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
