Re: [PATCH v2] mmc: sdhci-of-arasan: Add shutdown callback

[Ulf Hansson]

On Thu, 29 May 2025 at 12:49, Paul Alvin <alvin.paulp@xxxxxxx> wrote:
>
> Implement shutdown hook to suspend host and disable all mmc clocks to
> increase power saving during shutdown or reboot.

So how long is the shutdown process for the platform? What do we really gain?

In general we don't quite care about power-savings during shutdown, as
we are going to turn off things anyway, right?

Kind regards
Uffe

>
> Signed-off-by: Paul Alvin <alvin.paulp@xxxxxxx>
> ---
>
> Changes in v2:
> - Make use of platform suspend instead of driver suspend as driver
>   suspend will only get defined if PMC_SLEEP is configured which
>   results in build failure if it is not configured.
> - Updated commit description.
>
>  drivers/mmc/host/sdhci-of-arasan.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index 8c29676ab662..4abdad3c4e5b 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -2056,6 +2056,11 @@ static void sdhci_arasan_remove(struct platform_device *pdev)
>         clk_disable_unprepare(clk_ahb);
>  }
>
> +static void sdhci_arasan_shutdown(struct platform_device *pdev)
> +{
> +       sdhci_pltfm_suspend(&pdev->dev);
> +}
> +
>  static struct platform_driver sdhci_arasan_driver = {
>         .driver = {
>                 .name = "sdhci-arasan",
> @@ -2065,6 +2070,7 @@ static struct platform_driver sdhci_arasan_driver = {
>         },
>         .probe = sdhci_arasan_probe,
>         .remove = sdhci_arasan_remove,
> +       .shutdown = sdhci_arasan_shutdown,
>  };
>
>  module_platform_driver(sdhci_arasan_driver);
> --
> 2.44.1
>