From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 1/3] Revert "spi/pl022: fix spi-pl022 pm enable at probe" Date: Sun, 30 Sep 2012 11:14:18 +0100 Message-ID: <20120930101418.GF6933@n2100.arm.linux.org.uk> References: <1348831266-16721-1-git-send-email-ulf.hansson@stericsson.com> <1348831266-16721-2-git-send-email-ulf.hansson@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Ulf Hansson , Vipul Kumar Samar , Viresh Kumar , spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Ulf Hansson , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Linus Walleij Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org On Sun, Sep 30, 2012 at 10:44:17AM +0200, Linus Walleij wrote: > On Fri, Sep 28, 2012 at 1:21 PM, Ulf Hansson wrote: > > > From: Ulf Hansson > > > > This reverts commit 6887237cd7da904184dab2750504040c68f3a080. > > > > Signed-off-by: Ulf Hansson > > Why? > > It was removed in this commit, is it wrong? Linus, please read the previous thread on pl022. The long and short of it is that your commit 2fb30d1147c599f5657e8c62c862f9a0f58d9d99 (spi/pl022: enable runtime PM) is totally broken, and Michel came along trying to fix the resulting breakage by partially removing your commit in 6887237cd7da904184dab2750504040c68f3a080 (spi/pl022: fix spi-pl022 pm enable at probe). The reason why your commit is wrong is: pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); ret = pcdrv->probe(pcdev, id); So, adding this in spi-pl022 probe: + pm_runtime_enable(dev); + pm_runtime_resume(dev); makes the sequence: pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); pm_runtime_enable(dev); pm_runtime_resume(dev); which is absolute rubbish. Your commit should never have gone into any tree. The real answer is to revert both commits to get the driver back to a sane state, before then progressing with the driver in a sane manner. This is what Ulf is doing. ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://ad.doubleclick.net/clk;258768047;13503038;j? http://info.appdynamics.com/FreeJavaPerformanceDownload.html