Re: [PATCH v4 5/5] mmc: sdhci-of-arasan: implement enhanced strobe callback

[Adrian Hunter]

On 20/05/16 11:36, Shawn Lin wrote:
> Currently sdhci-arasan 5.1 can support enhanced strobe function,
> and we now limit it just for "arasan,sdhci-5.1". Add
> mmc-hs400-enhanced-strobe in DT to enable the function if we're
> sure our controller can support it.
> 
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> Reviewed-by: Doug Anderson <dianders@xxxxxxxxxxxx>

Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

> ---
> 
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/mmc/host/sdhci-of-arasan.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index b6f4c1d..533e2bc 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -25,7 +25,9 @@
>  #include "sdhci-pltfm.h"
>  
>  #define SDHCI_ARASAN_CLK_CTRL_OFFSET	0x2c
> +#define SDHCI_ARASAN_VENDOR_REGISTER	0x78
>  
> +#define VENDOR_ENHANCED_STROBE		BIT(0)
>  #define CLK_CTRL_TIMEOUT_SHIFT		16
>  #define CLK_CTRL_TIMEOUT_MASK		(0xf << CLK_CTRL_TIMEOUT_SHIFT)
>  #define CLK_CTRL_TIMEOUT_MIN_EXP	13
> @@ -79,6 +81,21 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
>  	}
>  }
>  
> +static void sdhci_arasan_hs400_enhanced_strobe(struct mmc_host *mmc,
> +					struct mmc_ios *ios)
> +{
> +	u32 vendor;
> +	struct sdhci_host *host = mmc_priv(mmc);
> +
> +	vendor = readl(host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
> +	if (ios->enhanced_strobe)
> +		vendor |= VENDOR_ENHANCED_STROBE;
> +	else
> +		vendor &= ~VENDOR_ENHANCED_STROBE;
> +
> +	writel(vendor, host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
> +}
> +
>  static struct sdhci_ops sdhci_arasan_ops = {
>  	.set_clock = sdhci_arasan_set_clock,
>  	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
> @@ -245,6 +262,9 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
>  			dev_err(&pdev->dev, "phy_power_on err.\n");
>  			goto err_phy_power;
>  		}
> +
> +		host->mmc_host_ops.hs400_enhanced_strobe =
> +					sdhci_arasan_hs400_enhanced_strobe;
>  	}
>  
>  	ret = sdhci_add_host(host);
>