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SubjectRe: [PATCH] mmc: host: sdhci: Fix the incorrect soft reset operation when runtime resuming
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On 15/07/19 1:58 PM, Baolin Wang wrote:
> In sdhci_runtime_resume_host() function, we will always do software reset
> for all, but according to the specification, we should issue reset command
> and reinitialize the SD/eMMC card.

Where does it say that?

> However, we only do reinitialize the
> SD/eMMC card when the SD/eMMC card are power down during runtime suspend.
>
> Thus for those platforms that do not power down the SD/eMMC card during
> runtime suspend, we should not do software reset for all.
> To fix this
> issue, we can add one condition to validate the MMC_CAP_AGGRESSIVE_PM
> to decide if we can do software reset for all or just reset command
> and data lines.
>
> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
> ---
> drivers/mmc/host/sdhci.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 9715834..470c5e0 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3333,7 +3333,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
> host->ops->enable_dma(host);
> }
>
> - sdhci_init(host, 0);
> + sdhci_init(host, !(mmc->caps & MMC_CAP_AGGRESSIVE_PM));

We have done a full reset for a long time, so it would be surprising to need
to change it.

What problem is it causing?

>
> if (mmc->ios.power_mode != MMC_POWER_UNDEFINED &&
> mmc->ios.power_mode != MMC_POWER_OFF) {
>

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