Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751498AbWINJWa (ORCPT ); Thu, 14 Sep 2006 05:22:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751502AbWINJWa (ORCPT ); Thu, 14 Sep 2006 05:22:30 -0400 Received: from sccrmhc14.comcast.net ([63.240.77.84]:14742 "EHLO sccrmhc14.comcast.net") by vger.kernel.org with ESMTP id S1751498AbWINJW3 (ORCPT ); Thu, 14 Sep 2006 05:22:29 -0400 Mime-Version: 1.0 (Apple Message framework v624) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit Cc: kernel list From: Matthew Locke Subject: PowerOP vs OPpoint Date: Thu, 14 Sep 2006 02:22:25 -0700 To: pm list X-Mailer: Apple Mail (2.624) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1989 Lines: 42 Unfortunately, there are two efforts underway that makes this confusing and I think require a bit more than the short summary requested. A one paragraph summary can't address the why and how. This email briefly describes the why and the differences. There are two main reasons for both these efforts: - existing power management interfaces do not enable the power management features on the latest SOC's used in embedded mobile devices - existing power management interfaces do not provide the API necessary to build power managers (userspace and/or kernel space) that optimize power consumption to level required by embedded mobile devices PowerOP Focus is on a platform independent interface for selecting and creating operating points. We want to get the basic power management block in place and build on it. Integrating with other existing power management interfaces as it makes sense. The first natural integration point is the cpufreq_driver layer in cpufreq and does not affect the userspace interface. OPpoint Goal is to show how all existing interfaces can use the operating point concept. It is more than an interface for selecting and creating operating points. It integrates with cpufreq and sleep states defining new userspace interfaces and using existing interfaces in different ways. There are a lot of issues with the OPpoint operating point interface that was discussed here: http://lists.osdl.org/pipermail/linux-pm/2006-August/003541.html . Many objections to the sleep state integration. Most of the negative comments about cpufreq are about the OPpoint patches. I have not seen or heard any justification for the OPpoint patches to create a different operating point interface. Matt - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/