From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Thu, 25 Oct 2012 16:51:43 +0100 Subject: [PATCH 2/6] pinctrl: Update clock handling for the pinctrl-nomadik GPIO driver In-Reply-To: References: <1351089926-32161-1-git-send-email-lee.jones@linaro.org> <1351089926-32161-3-git-send-email-lee.jones@linaro.org> Message-ID: <20121025155143.GK4008@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, 25 Oct 2012, Linus Walleij wrote: > On Thu, Oct 25, 2012 at 2:41 PM, Linus Walleij wrote: > > On Wed, Oct 24, 2012 at 4:45 PM, Lee Jones wrote: > > > >> The clock framework has changed somewhat and it's now better to > >> invoke clock_prepare_enable() and clk_disable_unprepare() rather > >> than the legacy clk_enable() and clk_disable() calls. This patch > >> converts the Nomadik Pin Control driver to the new framework. > >> > >> Signed-off-by: Lee Jones > > > > I was convinced that this is a good change but no regression, > > so applied to the devel branch for 3.8. > > > > I also removed the initial clk_prepare() so the reference count > > may actually go down to 0 for the GPIO block and the peripheral > > cluster eventually gets relaxed. > > Famous last words! > > The good news is that this actually works, and the refcount > *does* go down to zero and gate off entire peripheral > clusters. > > However that was not good because something vital in > some peripheral cluster died and killed the system :-D > > Lee, could to to track down the reason and fix it so the patch > can be applied? > > The only thing you need to do is to remove the superfluous > clk_prepare() right after the devm_clk_get() that hogs each > peripheral cluster. > > Probably some driver is needing a clk_get() or a clk_get_sys() is > needs to be added somewhere to bring up some vital cluster, > or there may be some out-of-tree driver needed to bring up the > cluster properly I have no clue... Maybe some cluster just > cannot be declocked like that. I leave work in 10 mins and won't be coding again for ~2.5 weeks. So if this is something you could squeeze in and fix-up, I'd be very grateful. Kind regards, Lee -- Lee Jones Linaro ST-Ericsson Landing Team Lead Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog