Re: [PATCH 2/2] mmc: fix mmc card disappearence on resume on ricoh mmc controllers

[Philip Langdale <philipl@overt.org>]

On Mon,  7 Jun 2010 00:28:51 +0300, Maxim Levitsky
<maximlevitsky@gmail.com> wrote:
> The reason was that it takes time for controller to detect the card.
> So wait a bit for the card to appear.
> In worst case scenario, when you suspend the system with mmc card,
> and actually remove it, the resume will be delayed maximum by 2 seconds

I suspect it's probably sending an SD id command to the card and then that
has to time out on MMC cards.

Acked-by: Philip Langdale <philipl@overt.org>

> Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
> ---
>  drivers/mmc/host/sdhci-pci.c |    3 ++-
>  drivers/mmc/host/sdhci.c     |   18 ++++++++++++++++++
>  drivers/mmc/host/sdhci.h     |    2 ++
>  3 files changed, 22 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
> index c4bcaeb..49d863c 100644
> --- a/drivers/mmc/host/sdhci-pci.c
> +++ b/drivers/mmc/host/sdhci-pci.c
> @@ -115,7 +115,8 @@ static const struct sdhci_pci_fixes sdhci_ricoh_mmc
= {
>  	.quirks		= SDHCI_QUIRK_32BIT_DMA_ADDR |
>  			  SDHCI_QUIRK_CLOCK_BEFORE_RESET |
>  			  SDHCI_QUIRK_NO_CARD_NO_RESET |
> -			  SDHCI_QUIRK_MISSING_CAPS
> +			  SDHCI_QUIRK_MISSING_CAPS |
> +			  SDHCI_QUIRK_WAIT_CARD_ON_RESUME
>  };
>  
>  static const struct sdhci_pci_fixes sdhci_ene_712 = {
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 483b78e..6cda505 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1612,6 +1612,24 @@ int sdhci_resume_host(struct sdhci_host *host)
>  {
>  	int ret;
>  
> +	/* Some controllers (especialy the ricoh mmc controller) delay
> +		card detection on resume (probably since the controller
> +		has to poke the card to determine if its MMC or not */
> +
> +	if (host->mmc->bus_ops && (host->quirks &
> +			SDHCI_QUIRK_WAIT_CARD_ON_RESUME)) {
> +
> +		unsigned long timeout = jiffies + msecs_to_jiffies(2000);
> +
> +		while (!time_after(jiffies, timeout))
> +			if (sdhci_readl(host, SDHCI_PRESENT_STATE)
> +							& SDHCI_CARD_PRESENT) {
> +				break;
> +			}
> +			cpu_relax();
> +	}
> +
> +
>  	if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
>  		if (host->ops->enable_dma)
>  			host->ops->enable_dma(host);
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index b1839a3..c9d099c 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -242,6 +242,8 @@ struct sdhci_host {
>  #define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC		(1<<26)
>  /* Controller is missing device caps. Use caps provided by host */
>  #define SDHCI_QUIRK_MISSING_CAPS			(1<<27)
> +/* Card doesn't appear immediatly on resume from low power state */
> +#define SDHCI_QUIRK_WAIT_CARD_ON_RESUME			(1<<28)
>  
>  	int			irq;		/* Device IRQ */
>  	void __iomem *		ioaddr;		/* Mapped address */

--phil