| Message ID | 20210508205658.91105-1-dev@lynxeye.de |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] dt-bindings: mmc: add no-mmc-hs400 flag | expand |
On Sat, 08 May 2021 22:56:57 +0200, Lucas Stach wrote: > HS400 requires a data strobe line in addition to the other MMC signal > lines, so if a board design neglects to wire up this signal, HS400 mode > is no available, even if both the controller and the eMMC are claiming > to support this mode. Add a DT flag to allow boards to disable the > HS400 support in this case. > > Signed-off-by: Lucas Stach <dev@lynxeye.de> > --- > Documentation/devicetree/bindings/mmc/mmc-controller.yaml | 5 +++++ > 1 file changed, 5 insertions(+) > Acked-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml index e141330c1114..ac80d09df3a9 100644 --- a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml +++ b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml @@ -220,6 +220,11 @@ properties: description: eMMC HS400 enhanced strobe mode is supported + no-mmc-hs400: + $ref: /schemas/types.yaml#/definitions/flag + description: + All eMMC HS400 modes are not supported. + dsr: description: Value the card Driver Stage Register (DSR) should be programmed
HS400 requires a data strobe line in addition to the other MMC signal lines, so if a board design neglects to wire up this signal, HS400 mode is no available, even if both the controller and the eMMC are claiming to support this mode. Add a DT flag to allow boards to disable the HS400 support in this case. Signed-off-by: Lucas Stach <dev@lynxeye.de> --- Documentation/devicetree/bindings/mmc/mmc-controller.yaml | 5 +++++ 1 file changed, 5 insertions(+)