From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zach Brown Subject: Re: [PATCH 1/2] sdhci-of-arasan: Add quirk and device tree parameter to fake CD bit Date: Fri, 26 Aug 2016 17:29:46 -0500 Message-ID: <20160826222945.GA6679@zach-desktop> References: <1472080984-17373-1-git-send-email-zach.brown@ni.com> <20160825105640.GA5439@remoulade> <20160825171539.GA13571@zach-desktop> <20160825180959.GA14705@remoulade> <20160825182621.GA14817@zach-desktop> <20160825182852.GB15000@remoulade> <20160825204645.GA19450@zach-desktop> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Ulf Hansson Cc: Mark Rutland , "devicetree@vger.kernel.org" , Lars-Peter Clausen , linux-mmc , Adrian Hunter , "linux-kernel@vger.kernel.org" , Rob Herring , "linux-arm-kernel@lists.infradead.org" , Michal Simek , =?iso-8859-1?Q?S=F6ren?= Brinkmann List-Id: devicetree@vger.kernel.org On Fri, Aug 26, 2016 at 09:42:38AM +0200, Ulf Hansson wrote: > On 25 August 2016 at 22:46, Zach Brown wrote: > > On Thu, Aug 25, 2016 at 07:28:55PM +0100, Mark Rutland wrote: > >> On Thu, Aug 25, 2016 at 01:26:22PM -0500, Zach Brown wrote: > >> > On Thu, Aug 25, 2016 at 07:10:00PM +0100, Mark Rutland wrote: > >> > > On Thu, Aug 25, 2016 at 12:15:44PM -0500, Zach Brown wrote: > >> > > > In cases where the card is non-removable then polling doesn't make sense. > >> > > > >> > > We have the non-removable property to describe that, so we can also look at that. > >> > > > >> > > > So it doesn't make sense to tie the test mode workaround into the broken-cd > >> > > > property, even though I agree the nature of the defect fits under the notion > >> > > > of the CD being broken. > >> > > > >> > > Maybe not solely on broken-cd, but I think that we dont necessarily need a new > >> > > DT property. As above, broken-cd, non-removable, and the compatible string may > >> > > together give the kernel enough information to choose the right thing to do. > >> > > > >> > > Thanks, > >> > > Mark. > >> > > >> > I'm not sure if I understand your suggestion completely. Are you suggesting > >> > setting both the broken-cd and non-removable properties? That would make sense, > >> > but my understanding was that the two properities are not meant to co-exist. In > >> > /Documentation/devicetree/bindings/mmc/mmc.txt it states that only one should > >> > be supplied. Don't the two properties conflict with each other? > >> > >> They do for the cases that exist today, but given we're updating the document > >> anyway, we could simply clarify the cases in which the two can sanely co-exist > >> (e.g. for this particular IP block). > > No, please! > > Depending on the SDHCI variant there is already some difference on how > broken-cd is treated. > > Let's not add yet another, as I think it will be too complicated for > people to understand the bindings. > Shawn Lin pointed out that there might be instances of the arasan controller that don't have the behavior the patch addresses. Having a new DT binding specific for this case would avoid needing to maintain a list of controllers that need the fix. > >> > >> Thanks, > >> Mark. > > > > That makes sense. I'll change the documentation for broken-cd and non-removable > > in the IP specific document and change the driver accordingly. > > I rather have a new DT binding specific for this case. > > Perhaps there's a better name than "fake-cd". How about "force-cd", or > if someone can come up with a better name. > > Kind regards > Uffe I've been trying to come up with a better name. Here are a few ideas cd-not-wired needs-test-cd fails-without-force-cd