[PATCH 1/2] sdhci: Add device tree property broken-highspeed

From	Zach Brown <zach.brown@ni.com>
Newsgroups	linux.kernel
Subject	[PATCH 1/2] sdhci: Add device tree property broken-highspeed
Date	2016-10-18 17:40 +0200
Message-ID	<stEEF-3BE-3@gated-at.bofh.it> (permalink)
References	<stEEF-3BE-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Certain board configurations can make highspeed malfuction 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 broken-highspeed property will let the sdhci driver know that
highspeed will not work.

Signed-off-by: Zach Brown <zach.brown@ni.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 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..a2b298c 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
+- 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

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[PATCH 1/2] sdhci: Add device tree property broken-highspeed Zach Brown <zach.brown@ni.com> - 2016-10-18 17:40 +0200

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