From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: Re: nokia 770 [was Re: community PM requirements/issues and PowerOP] Date: Wed, 13 Dec 2006 17:58:02 -0500 Message-ID: <20061213225802.GN2418@redhat.com> References: <20060914101704.GA17820@elf.ucw.cz> <457FEE17.8080806@gmail.com> <20061213210359.GC11843@elf.ucw.cz> <200612131332.58606.david-b@pacbell.net> <20061213215351.GE2418@redhat.com> <5062AF8D-E97F-41D2-8602-59578F2B4655@comcast.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <5062AF8D-E97F-41D2-8602-59578F2B4655@comcast.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.osdl.org Errors-To: linux-pm-bounces@lists.osdl.org To: Matthew Locke Cc: linux-pm@lists.osdl.org, scott.preece@motorola.com, Pavel Machek , Amit Kucheria List-Id: linux-pm@vger.kernel.org On Wed, Dec 13, 2006 at 02:50:12PM -0800, Matthew Locke wrote: > = > >>> I'd find that it's used on N770, as a good way to kick in low = > >>> voltage > >>> operation modes. > >> > >> Except that cpufreq doesn't really support voltage changes > > > > The majority of cpufreq drivers in the tree right now support > > voltage scaling just fine. > = > Ok, let's reword my sentence. The cpufreq interface does not support = > voltage as a parameter Please explain why this is useful at all. Under what circumstance is "Set the CPU voltage to 1.2V" a useful thing for a user, sysadmin, or application to do ? The voltage something runs at is utterly irrelevant to all the above. Given it's inherently tied to the speed a chip runs at, which makes a lot more sense for all the above scenarios to change, we export that inst= ead. AFAICS, exposing voltages to userspace would be completely pointless. Dave -- = http://www.codemonkey.org.uk