From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034570AbcIWUXq (ORCPT ); Fri, 23 Sep 2016 16:23:46 -0400 Received: from skprod3.natinst.com ([130.164.80.24]:44792 "EHLO ni.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1030280AbcIWUXU (ORCPT ); Fri, 23 Sep 2016 16:23:20 -0400 From: Zach Brown To: ulf.hansson@linaro.org Cc: adrian.hunter@intel.com, robh+dt@kernel.org, mark.rutland@arm.com, linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, zach.brown@ni.com Subject: [RFC 1/2] sdhci: Add device tree property sd-broken-highspeed Date: Fri, 23 Sep 2016 15:01:08 -0500 Message-Id: <1474660869-15532-2-git-send-email-zach.brown@ni.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1474660869-15532-1-git-send-email-zach.brown@ni.com> References: <1474660869-15532-1-git-send-email-zach.brown@ni.com> X-MIMETrack: Itemize by SMTP Server on US-AUS-MGWOut2/AUS/H/NIC(Release 8.5.3FP6 HF1218|December 12, 2014) at 09/23/2016 03:01:10 PM, Serialize by Router on US-AUS-MGWOut2/AUS/H/NIC(Release 8.5.3FP6 HF1218|December 12, 2014) at 09/23/2016 03:23:11 PM, Serialize complete at 09/23/2016 03:23:11 PM X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-09-23_07:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Certain board configurations can make highspeed malfunction due to timing issues. In these cases a way is needed to force the controller and card into standard speed even if they otherwise appear to be capable of highspeed. The sd-broken-highspeed property will let the sdhci driver know that highspeed will not work. Signed-off-by: Zach Brown --- Documentation/devicetree/bindings/mmc/mmc.txt | 2 ++ 1 file changed, 2 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt index 8a37782..59332ea 100644 --- a/Documentation/devicetree/bindings/mmc/mmc.txt +++ b/Documentation/devicetree/bindings/mmc/mmc.txt @@ -52,6 +52,8 @@ Optional properties: - no-sdio: controller is limited to send sdio cmd during initialization - no-sd: controller is limited to send sd cmd during initialization - no-mmc: controller is limited to send mmc cmd during initialization +- sd-broken-highspeed: Highspeed is broken, even if the controller and card + themselves claim they support highspeed. *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line polarity properties, we have to fix the meaning of the "normal" and "inverted" -- 2.7.4