[RFC PATCH 1/7] mmc: sdhci: add quirk for broken 3.0V support

[Anton Vorontsov]

On Fri, Jun 20, 2014 at 05:35:22PM +0800, Vincent Yang wrote:
> This patch defines a quirk for platforms unable
> to enable 3.0V support.
> It is a preparation and will be used by Fujitsu
> SDHCI controller f_sdh30 driver.
> 
> Signed-off-by: Vincent Yang <Vincent.Yang at tw.fujitsu.com>

I don't think you need this patch. Instead, you can exclude 3V using the
voltage-ranges = <> in the device tree.

Thanks,

Anton

>  drivers/mmc/host/sdhci.c  | 3 +++
>  include/linux/mmc/sdhci.h | 2 ++
>  2 files changed, 5 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 47055f3..523075f 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3069,6 +3069,9 @@ int sdhci_add_host(struct sdhci_host *host)
>  	}
>  #endif /* CONFIG_REGULATOR */
>  
> +	if (host->quirks2 & SDHCI_QUIRK2_NO_3_0_V)
> +		caps[0] &= ~SDHCI_CAN_VDD_300;
> +
>  	/*
>  	 * According to SD Host Controller spec v3.00, if the Host System
>  	 * can afford more than 150mA, Host Driver should set XPC to 1. Also
> diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
> index 08abe99..cac0958 100644
> --- a/include/linux/mmc/sdhci.h
> +++ b/include/linux/mmc/sdhci.h
> @@ -98,6 +98,8 @@ struct sdhci_host {
>  #define SDHCI_QUIRK2_BROKEN_HS200			(1<<6)
>  /* Controller does not support DDR50 */
>  #define SDHCI_QUIRK2_BROKEN_DDR50			(1<<7)
> +/* The system physically doesn't support 3.0v, even if the host does */
> +#define SDHCI_QUIRK2_NO_3_0_V				(1<<8)
>  
>  	int irq;		/* Device IRQ */
>  	void __iomem *ioaddr;	/* Mapped address */
> -- 
> 1.9.0