[PATCH] mmc: sdhci: fixed regulator control when suspend/resume

[PATCH] mmc: sdhci: fixed regulator control when suspend/resume

[Jaehoon Chung]

Suspend/resume is working always enable regulator after resuming. 
(if there is host->vmmc)
I assume that if regulator is enabled, card is inserted.
Then We need to restore "vmmc".

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/mmc/host/sdhci.c  |    8 +++++---
 include/linux/mmc/sdhci.h |    1 +
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9e15f41..70cbbd6 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1663,8 +1663,10 @@ int sdhci_suspend_host(struct sdhci_host *host, pm_message_t state)
 
 	free_irq(host->irq, host);
 
-	if (host->vmmc)
+	if (host->vmmc && regulator_is_enabled(host->vmmc)) {
 		ret = regulator_disable(host->vmmc);
+		host->restore_vmmc = true;
+	}
 
 	return ret;
 }
@@ -1675,8 +1677,8 @@ int sdhci_resume_host(struct sdhci_host *host)
 {
 	int ret;
 
-	if (host->vmmc) {
-		int ret = regulator_enable(host->vmmc);
+	if (host->vmmc && host->restore_vmmc) {
+		ret = regulator_enable(host->vmmc);
 		if (ret)
 			return ret;
 	}
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 83bd9f7..1c38261 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -92,6 +92,7 @@ struct sdhci_host {
 	const struct sdhci_ops *ops;	/* Low level hw interface */
 
 	struct regulator *vmmc;	/* Power regulator */
+	bool restore_vmmc;	/* Restore vmmc */
 
 	/* Internal data */
 	struct mmc_host *mmc;	/* MMC structure */
-- 

Re: [PATCH] mmc: sdhci: fixed regulator control when suspend/resume

[Wolfram Sang]

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On Thu, Apr 07, 2011 at 01:23:52PM +0900, Jaehoon Chung wrote:
> Suspend/resume is working always enable regulator after resuming. 
> (if there is host->vmmc)

The regulator is enabled during add_host. How could it not be enabled in
suspend?

>  	struct regulator *vmmc;	/* Power regulator */
> +	bool restore_vmmc;	/* Restore vmmc */

If you can explain the above, this should be turned into a SDHCI_-flag IMHO.

Regards,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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Re: [PATCH] mmc: sdhci: fixed regulator control when suspend/resume

[Jae hoon Chung]

Hi, Wolfram..

2011/4/9 Wolfram Sang <w.sang@pengutronix.de>:
> On Thu, Apr 07, 2011 at 01:23:52PM +0900, Jaehoon Chung wrote:
>> Suspend/resume is working always enable regulator after resuming.
>> (if there is host->vmmc)
>
> The regulator is enabled during add_host. How could it not be enabled in
> suspend?

you're right..When running add_host, enabled the regulator "vmmc".
I'm missing this patch.sorry ^^
Actually,If controller didn't detect the card, i added disable
function in sdhci-s3c.c.
Then regulator is disabled when enter suspend. :)

But i didn't find methed to disable in sdhci.c.
(i think that should be find to use CDn pin)

I'll resend the modified patch.
If you have other method, let me know your opinion.

Thanks very much for your comment.
>
>>       struct regulator *vmmc; /* Power regulator */
>> +     bool restore_vmmc;      /* Restore vmmc */
>
> If you can explain the above, this should be turned into a SDHCI_-flag IMHO.
>
> Regards,
>
>   Wolfram
>
> --
> Pengutronix e.K.                           | Wolfram Sang                |
> Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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