[RFC 1/2] sdhci: Add device tree property sd-broken-highspeed
From: Zach Brown <hidden>
Date: 2016-09-23 20:23:46
Also in:
linux-mmc, lkml
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, open firmware and flattened device tree bindings, the rest · Maintainers:
Ulf Hansson, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
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 <redacted> --- 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