[PATCH v9 2/3] mmc: core: Add support for SDIO wakeup interrupt

[Ulf Hansson]

On Tue, 29 Mar 2022 at 05:29, Axe Yang <axe.yang at mediatek.com> wrote:
>
> If wakeup-source flag is set in host dts node, parse EAI information
> from SDIO CCCR interrupt externsion segment for in-band wakeup. If
> async interrupt is supported by SDIO card then enable it and set
> enable_async_irq flag in sdio_cccr structure to 1. The parse flow is
> implemented in sdio_read_cccr().
>
> Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>
> Signed-off-by: Axe Yang <axe.yang at mediatek.com>
> ---
>  drivers/mmc/core/sdio.c  | 17 +++++++++++++++++
>  include/linux/mmc/card.h |  8 +++++++-
>  include/linux/mmc/sdio.h |  5 +++++
>  3 files changed, 29 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
> index 25799accf8a0..4898c5e9a299 100644
> --- a/drivers/mmc/core/sdio.c
> +++ b/drivers/mmc/core/sdio.c
> @@ -226,6 +226,23 @@ static int sdio_read_cccr(struct mmc_card *card, u32 ocr)
>                                 card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_C;
>                         if (data & SDIO_DRIVE_SDTD)
>                                 card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_D;
> +
> +                       if (card->host->pm_caps & MMC_PM_WAKE_SDIO_IRQ) {

After a second thought, I think we can just skip this check. The
MMC_PM_WAKE_SDIO_IRQ indicates that the host supports SDIO IRQs as
*system wakeups*.

But, in fact, I think we want this feature to be enabled to allow
waking up for runtime_suspend (RPM_SUSPENDED) too.

> +                               ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTERRUPT_EXT, 0,
> +                                                      &data);
> +                               if (ret)
> +                                       goto out;
> +
> +                               if (data & SDIO_INTERRUPT_EXT_SAI) {
> +                                       data |= SDIO_INTERRUPT_EXT_EAI;
> +                                       ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_INTERRUPT_EXT,
> +                                                              data, NULL);
> +                                       if (ret)
> +                                               goto out;
> +
> +                                       card->cccr.enable_async_irq = 1;
> +                               }
> +                       }
>                 }

[...]

Other than the above, this looks good to me!

Kind regards
Uffe