From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Ball Subject: Re: [PATCH] mmc: dt: Add 'broken-cd' DT binding Date: Wed, 22 Aug 2012 09:54:30 -0400 Message-ID: <87txvv3ucp.fsf@octavius.laptop.org> References: <1345547371-6784-1-git-send-email-thomas.abraham@linaro.org> <87k3ws5uhs.fsf@octavius.laptop.org> <201208211208.49987.arnd@arndb.de> <87393g5mic.fsf@octavius.laptop.org> <20120822122655.GW24242@S2101-09.ap.freescale.net> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20120822122655.GW24242@S2101-09.ap.freescale.net> (Shawn Guo's message of "Wed, 22 Aug 2012 20:26:56 +0800") Sender: linux-samsung-soc-owner@vger.kernel.org To: Shawn Guo Cc: Arnd Bergmann , Thomas Abraham , linux-mmc@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-samsung-soc@vger.kernel.org, grant.likely@secretlab.ca, rob.herring@calxeda.com, patches@linaro.org, Wolfram Sang List-Id: linux-mmc@vger.kernel.org Hi Shawn, On Wed, Aug 22 2012, Shawn Guo wrote: > mmc: sdhci: Always pass clock request value zero to set_clock host op > > To allow the set_clock host op to disable the SDCLK source when not > needed, always call the host op when the requested clock speed is > zero. Do this even if host->clock already equals zero, because > the SDHCI driver may set that value (without calling the host op) > to force an update at the next (non-zero-speed) call. > > Signed-off-by: Todd Poynor > Acked-by: Adrian Hunter > Signed-off-by: Chris Ball > > Reverting the commit will get "controller" mode back to work. Weird; I wonder how that's related to card detection. I'm afraid it's ultimately a driver bug -- esdhc should be able to handle having set_clock called with a value of 0. It seems to have a case in esdhc_set_clock() for 0, so I'm surprised it's not working. What's the symptom of the failure? Can you debug some more? Thanks, - Chris. -- Chris Ball One Laptop Per Child