diff mbox series

mmc: core: Wait for Vdd to settle on card power off

Message ID 20250211214611.469260-1-erick.shepherd@ni.com (mailing list archive)
State New
Headers show
Series mmc: core: Wait for Vdd to settle on card power off | expand

Commit Message

Erick Shepherd Feb. 11, 2025, 9:46 p.m. UTC 
The SD spec version 6.0 section 6.4.1.5 requires that Vdd must be
lowered to less than 0.5V for a minimum of 1 ms when powering off a
card. Increase our wait to 15 ms so that voltage has time to drain down
to 0.5V.

Signed-off-by: Kyle Roeschley <kyle.roeschley@ni.com>
Signed-off-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: Erick Shepherd <erick.shepherd@ni.com>
---
 drivers/mmc/host/sdhci.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Avri Altman Feb. 13, 2025, 10:22 a.m. UTC | #1 
> Subject: [PATCH] mmc: core: Wait for Vdd to settle on card power off
                                              ^^^^
Should be a host patch?

> 
> The SD spec version 6.0 section 6.4.1.5 requires that Vdd must be lowered to
> less than 0.5V for a minimum of 1 ms when powering off a card. Increase our
> wait to 15 ms so that voltage has time to drain down to 0.5V.
> 
> Signed-off-by: Kyle Roeschley <kyle.roeschley@ni.com>
> Signed-off-by: Brad Mouring <brad.mouring@ni.com>
> Signed-off-by: Erick Shepherd <erick.shepherd@ni.com>
Acked-by: Avri Altman <avri.altman@sandisk.com>

> ---
>  drivers/mmc/host/sdhci.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index
> f4a7733a8ad2..b15a1f107549 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2415,6 +2415,9 @@ void sdhci_set_ios(struct mmc_host *mmc, struct
> mmc_ios *ios)
>  	else
>  		sdhci_set_power(host, ios->power_mode, ios->vdd);
> 
> +	if (ios->power_mode == MMC_POWER_OFF)
> +		mdelay(15);
> +
>  	if (host->ops->platform_send_init_74_clocks)
>  		host->ops->platform_send_init_74_clocks(host, ios-
> >power_mode);
> 
> --
> 2.43.0
>
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index f4a7733a8ad2..b15a1f107549 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2415,6 +2415,9 @@  void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	else
 		sdhci_set_power(host, ios->power_mode, ios->vdd);
 
+	if (ios->power_mode == MMC_POWER_OFF)
+		mdelay(15);
+
 	if (host->ops->platform_send_init_74_clocks)
 		host->ops->platform_send_init_74_clocks(host, ios->power_mode);