Re: [PATCH v7 2/3] dt-bindings: mmc: Add reset-card-at-resume property

From: Rob Herring

Date: Fri Aug 07 2026 - 10:19:15 EST


On Wed, Aug 05, 2026 at 06:24:59PM -0400, Kamal Dasu wrote:
> On some platforms, firmware or other hardware accesses the card
> during suspend/resume, before the kernel's own resume path has run,
> leaving the card in a state the kernel can no longer assume it knows.
> Add a flag property so such boards can tell the mmc core the card
> needs to be reset before it can be used again.
>
> This is expected to be paired with keep-power-in-suspend on boards
> whose firmware needs the card to stay powered and live throughout
> suspend: since the card is never power-cycled, nothing else would
> force it back to a known state on resume.
>
> Signed-off-by: Kamal Dasu <kamal.dasu@xxxxxxxxxxxx>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> ---
> Changes in v7:
> - Added Krzysztof's Reviewed-by.
> - No other change here; patch 3/3 now requires this property
> alongside keep-power-in-suspend for (e)MMC rather than treating
> them as fully independent in the driver -- see that patch's
> changelog.
>
> Changes in v6:
> - New patch, per Ulf's suggestion: rather than fold "needs a reset
> at resume" into keep-power-in-suspend's own meaning, describe it
> as its own independent property, so the two can be combined only
> where actually needed (brcmstb sets both; SDIO's existing
> keep-power-in-suspend users are unaffected and set neither this
> nor a reset).
>
> Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml | 7 +++++++
> 1 file changed, 7 insertions(+)

sashiko issue needs to be addressed