[PATCH v4 2/6] mmc: sdhci-esdhc-imx: add tuning-step seting support

Dong Aisheng aisheng.dong at freescale.com
Fri Aug 7 00:40:20 PDT 2015


On Wed, Aug 05, 2015 at 06:38:38PM +0800, Haibo Chen wrote:
> tuning-step is the delay cell steps in tuning procedure. The default value
> of tuning-step is 1. Some boards or cards need another value to pass the
> tuning procedure. For example, imx7d-sdb board need the tuning-step value
> as 2, otherwise it can't pass the tuning procedure.
> 
> So this patch add the tuning-step setting in driver, so that user can set
> the tuning-step value in dts.
> 
> Signed-off-by: Haibo Chen <haibo.chen at freescale.com>
> ---
>  drivers/mmc/host/sdhci-esdhc-imx.c          | 9 +++++++++
>  include/linux/platform_data/mmc-esdhc-imx.h | 1 +
>  2 files changed, 10 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 48f009c..803d24f 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -75,6 +75,7 @@
>  #define ESDHC_STD_TUNING_EN		(1 << 24)
>  /* NOTE: the minimum valid tuning start tap for mx6sl is 1 */
>  #define ESDHC_TUNING_START_TAP		0x1
> +#define ESDHC_TUNING_STEP_SHIFT		16
>  
>  /* pinctrl state */
>  #define ESDHC_PINCTRL_STATE_100MHZ	"state_100mhz"
> @@ -474,6 +475,7 @@ static void esdhc_writew_le(struct sdhci_host *host, u16 val, int reg)
>  		} else if (imx_data->socdata->flags & ESDHC_FLAG_STD_TUNING) {
>  			u32 v = readl(host->ioaddr + SDHCI_ACMD12_ERR);
>  			u32 m = readl(host->ioaddr + ESDHC_MIX_CTRL);
> +			u32 tuning_ctrl;
>  			if (val & SDHCI_CTRL_TUNED_CLK) {
>  				v |= ESDHC_MIX_CTRL_SMPCLK_SEL;
>  			} else {
> @@ -484,6 +486,11 @@ static void esdhc_writew_le(struct sdhci_host *host, u16 val, int reg)
>  			if (val & SDHCI_CTRL_EXEC_TUNING) {
>  				v |= ESDHC_MIX_CTRL_EXE_TUNE;
>  				m |= ESDHC_MIX_CTRL_FBCLK_SEL;
> +				tuning_ctrl = readl(host->ioaddr + ESDHC_TUNING_CTRL);
> +				tuning_ctrl |= ESDHC_STD_TUNING_EN | ESDHC_TUNING_START_TAP;
> +				if (imx_data->boarddata.tuning_step)
> +					tuning_ctrl |= imx_data->boarddata.tuning_step << ESDHC_TUNING_STEP_SHIFT;
> +					writel(tuning_ctrl, host->ioaddr + ESDHC_TUNING_CTRL);

Is there a code indent issue here?
Otherwise, the patch looks good to me.

Regards
Dong Aisheng

>  			} else {
>  				v &= ~ESDHC_MIX_CTRL_EXE_TUNE;
>  			}
> @@ -964,6 +971,8 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev,
>  	if (gpio_is_valid(boarddata->wp_gpio))
>  		boarddata->wp_type = ESDHC_WP_GPIO;
>  
> +	of_property_read_u32(np, "fsl,tuning-step", &boarddata->tuning_step);
> +
>  	if (of_find_property(np, "no-1-8-v", NULL))
>  		boarddata->support_vsel = false;
>  	else
> diff --git a/include/linux/platform_data/mmc-esdhc-imx.h b/include/linux/platform_data/mmc-esdhc-imx.h
> index e1571ef..95ccab3 100644
> --- a/include/linux/platform_data/mmc-esdhc-imx.h
> +++ b/include/linux/platform_data/mmc-esdhc-imx.h
> @@ -45,5 +45,6 @@ struct esdhc_platform_data {
>  	int max_bus_width;
>  	bool support_vsel;
>  	unsigned int delay_line;
> +	unsigned int tuning_step;       /* The delay cell steps in tuning procedure */
>  };
>  #endif /* __ASM_ARCH_IMX_ESDHC_H */
> -- 
> 1.9.1
> 



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