Re: [PATCH v3 0/2] mmc: Add power_off_delay_us support

[Ulf Hansson]

On Thu, Aug 6, 2026 at 6:23 PM Judith Mendez <jm@xxxxxx> wrote:
>
> This series adds power_off_delay_us support for MMC controllers,
> enabling boards to specify custom delays after MMC power off to work around
> hardware issues such as slow RC circuites on MMC VDD rails.
>
> Rather than adding host driver-specific workarounds, we abstract the
> implementation into the MMC core and pickup the delay value with a device
> tree property (power-off-delay-us). This allows any board with slow
> power off requirements to configure the necessary delay without code
> changes.
>
> The solution is minimal and follows existing patterns as with
> power_delay_ms. The allowed minimum value = 0 ms (early return).
> The default value is 1000us to not deviate from the
> original 1ms delay set in mmc_power_off().
>
> Link to v1:
> https://lore.kernel.org/all/20260716232641.2659710-1-jm@xxxxxx/
> Link to v2:
> https://lore.kernel.org/all/20260722205701.372789-1-jm@xxxxxx/
>
> Changes since v2:
> - allow 0us as lowest possible value (early return)
> - Change custom logic in mmc_delay_us() to use fsleep()
> - drop dt parsing checkers
>
> Judith Mendez (2):
>   dt-bindings: mmc: Add power-off-delay-us property
>   mmc: core: Add power-off-delay-us support
>
>  .../devicetree/bindings/mmc/mmc-controller-common.yaml | 10 ++++++++++
>  drivers/mmc/core/core.c                                |  2 +-
>  drivers/mmc/core/core.h                                |  8 ++++++++
>  drivers/mmc/core/host.c                                |  4 ++++
>  include/linux/mmc/host.h                               |  1 +
>  5 files changed, 24 insertions(+), 1 deletion(-)
>
> --
> 2.54.0
>

The series applied for next, thanks!

Kind regards
Uffe