diff mbox

[RFC,1/2] mmc: sdhci: dt: Add device tree property sdhci-cap-speed-modes-broken

Message ID 1476824736-9337-2-git-send-email-zach.brown@ni.com (mailing list archive)
State New, archived
Headers show

Commit Message

Zach Brown Oct. 18, 2016, 9:05 p.m. UTC
On some systems the sdhci capabilty registers are incorrect for one
reason or another.

The sdhci-cap-speed-modes-broken property will let the driver know that
the sdhci capability registers should not be relied on for speed modes.
Instead the driver should check the mmc generic DT bindings.

Signed-off-by: Zach Brown <zach.brown@ni.com>
---
 Documentation/devicetree/bindings/mmc/mmc.txt | 3 +++
 1 file changed, 3 insertions(+)

Comments

Rob Herring (Arm) Oct. 26, 2016, 9:03 p.m. UTC | #1
On Tue, Oct 18, 2016 at 04:05:35PM -0500, Zach Brown wrote:
> On some systems the sdhci capabilty registers are incorrect for one
> reason or another.
> 
> The sdhci-cap-speed-modes-broken property will let the driver know that
> the sdhci capability registers should not be relied on for speed modes.
> Instead the driver should check the mmc generic DT bindings.
> 
> Signed-off-by: Zach Brown <zach.brown@ni.com>
> ---
>  Documentation/devicetree/bindings/mmc/mmc.txt | 3 +++
>  1 file changed, 3 insertions(+)

Acked-by: Rob Herring <robh@kernel.org>
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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index 8a37782..671d6c0 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -52,6 +52,9 @@  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
+- sdhci-cap-speed-modes-broken: One or more of the bits in the sdhci
+  capabilities registers representing speed modes are incorrect. All the bits
+  representing speed modes should be ignored.
 
 *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"