[PATCH V1 1/3] dt-bindings: mmc: qcom: Document level shifter flag for SD card

[Sarthak Garg]

Introduce a flag to indicate if the Qualcomm platform has a level
shifter for SD cards. With level shifter addition some extra delay is
seen on RX data path leading to CRC errors. To compensate these delays
and avoid CRC errors below things needs to be done:

1) Enable tuning for SDR50 mode
2) Limit HS mode frequency to 37.5MHz from 50MHz

Add this flag for all targets with a level shifter to handle these
issues for SD card.

Signed-off-by: Sarthak Garg <quic_sartgarg@xxxxxxxxxxx>
---
 Documentation/devicetree/bindings/mmc/sdhci-msm.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml b/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
index b32253c60919..14f1ec9ae5bd 100644
--- a/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
+++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
@@ -131,6 +131,9 @@ properties:
     $ref: /schemas/types.yaml#/definitions/uint32
     description: platform specific settings for DLL_CONFIG reg.
 
+  qcom,use-level-shifter:
+    description: Flag to indicate if platform has level shifter for SD card.
+
   iommus:
     minItems: 1
     maxItems: 8
-- 
2.17.1