On Tue, Aug 23, 2016 at 09:22:29AM +0300, Adrian Hunter wrote: > On 23/08/16 01:55, Zach Brown wrote: > > From: Jaeden Amero <jaeden.amero@xxxxxx> > > > > On some devices, CD is broken so that we must force the SDHCI into test > > mode and set CD, so that it always detects an SD card as present. > > > > In order to get a device with broken CD working, we had previously > > always set the SDHCI into test mode. Unfortunately, this had the side > > effect of making all SD cards used with our Linux kernels undetectable > > and non-removable. > > > > By making this "SD test mode" setting optional via a quirk, we can avoid > > this side effect for devices other than the device with broken CD. > > Additionally, we add a device parameter to sdhci-pltfm to allow all > > SDHCI drivers to enable this quirk. > > Generally new quirks are not acceptable, but I don't see how test mode helps > very much since you still don't get any card detection events. If you > really need test mode, please explain more about how it helps (as opposed to > polling for example). > > Polling doesnt work in our case, since the issue lies with the SD controller itself. The SD controller in xilinx zynq devices requires the CDn signal to work. http://www.xilinx.com/support/answers/61064.html We have a situation where the controller requires the signal, but we can't use any of our pins to supply it. With test mode we can get the controller into a state where it works despite not having the signal. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
