From mboxrd@z Thu Jan 1 00:00:00 1970 From: Francesco VIRLINZI Subject: Re: Montreal Linux Power Management Mini-Summit, July 13, 2009 - Meeting Notes Date: Wed, 02 Sep 2009 10:36:55 +0200 Message-ID: <4A9E2EA7.8080700@st.com> References: <63386a3d0909011522m7a175d3eyb3bbe8a29a5fd104@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <63386a3d0909011522m7a175d3eyb3bbe8a29a5fd104@mail.gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Linus Walleij Cc: Linux Power Management List , linux-arm-kernel@lists.infradead.org List-Id: linux-pm@vger.kernel.org Hi Linus FYI: I'm going to present a generic linux clock framework during the CELF-Europe @ http://www.embeddedlinuxconference.com/elc_europe09/sessions.html#Virlinzi It's integrated in the LDM via platform_driver and platform_device. It would be a proposal but it doesn't use the CPUFreq. It uses struct clk to identify each phisical the clock in the system and it adds clock information to the platform_device to link each device to the clock it uses. Regards Francesco On 09/02/2009 12:22 AM, Linus Walleij wrote: > 2009/7/31 Len Brown: > > >> A Linux Power Management "mini-summit" was held on July 13th, 2009 - >> on the first day of the Montreal Linux Symposium. >> (...) >> > >> SH running cpufreq on top of clock framework >> cpufreq has notifiers, clock framework does not >> > Hm! Paul can you elaborate on what that was about. > > I've felt a need for clock notifiers and we've cheated by using > CPUfreq because it so happens that the clocking in system-wide > and whenever the CPU freq change so may the other clocks. > > But if I put code into a PrimeCell MMC/SPI/I2C driver or whatever and > use CPUfreq that's very unelegant, and for other platforms where > the CPU freq don't change when this particular device clk freq > change plain misleading. > > A clk pre/postchange notifier pair would really help and would > make for elegant drivers that can handle clock freq transitions. > > Has anyone poked at this? > > Linus Walleij > _______________________________________________ > linux-pm mailing list > linux-pm@lists.linux-foundation.org > https://lists.linux-foundation.org/mailman/listinfo/linux-pm > >