[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20250801084518.2259767-3-quic_sartgarg@quicinc.com>
Date: Fri, 1 Aug 2025 14:15:16 +0530
From: Sarthak Garg <quic_sartgarg@...cinc.com>
To: Ulf Hansson <ulf.hansson@...aro.org>, Rob Herring <robh@...nel.org>,
Krzysztof Kozlowski <krzk+dt@...nel.org>,
Conor Dooley <conor+dt@...nel.org>,
Bjorn Andersson <andersson@...nel.org>,
Konrad Dybcio <konradybcio@...nel.org>,
Adrian Hunter <adrian.hunter@...el.com>
Cc: linux-mmc@...r.kernel.org, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
quic_cang@...cinc.com, quic_nguyenb@...cinc.com,
quic_rampraka@...cinc.com, quic_pragalla@...cinc.com,
quic_sayalil@...cinc.com, quic_nitirawa@...cinc.com,
quic_bhaskarv@...cinc.com, kernel@....qualcomm.com,
Sarthak Garg <quic_sartgarg@...cinc.com>
Subject: [PATCH V4 2/4] dt-bindings: mmc: controller: Add max-sd-hs-frequency property
Some platforms may require limiting the maximum frequency used in SD
High-Speed (HS) mode due to board-level hardware constraints. For
example, certain boards may include level shifters or other components
that cannot reliably operate at the default 50 MHz HS frequency.
Introduce a new optional device tree property max-sd-hs-frequency to
limit the maximum frequency (in Hz) used for SD cards operating in
High-Speed (HS) mode.
Signed-off-by: Sarthak Garg <quic_sartgarg@...cinc.com>
---
.../devicetree/bindings/mmc/mmc-controller-common.yaml | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
index 9a7235439759..6c2529b976d1 100644
--- a/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
+++ b/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
@@ -93,6 +93,16 @@ properties:
minimum: 400000
maximum: 384000000
+ max-sd-hs-frequency:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Maximum frequency (in Hz) to be used for SD cards operating in
+ High-Speed (HS) mode. This is useful for board-specific limitations,
+ such as level shifters or others where the card cannot reliably
+ operate at the default 50 MHz HS frequency.
+ minimum: 400000
+ maximum: 50000000
+
disable-wp:
$ref: /schemas/types.yaml#/definitions/flag
description:
--
2.34.1
Powered by blists - more mailing lists