[U-Boot] [PATCH] powerpc/esdhc: force the bus width to 4bit

[Marek Vasut <marex@denx.de>]

Dear Chang-Ming.Huang at freescale.com,

> From: Jerry Huang <Chang-Ming.Huang@freescale.com>
> 
> For the current u-boot codes, only 4bit/1bit SD/SDHC bus width is support.
> So for MMC card, we also support 4bit bus width,
> otherwiase, we will get the 12bit bus width, which is not correct:

Andy ... can you please explain? I don't quite understand the problem, I thought 
we had no problem supporting 8bit mmc (esp. if the controller handles that for 
us mostly).

> => mmcinfo
> Device: FSL_SDHC
> Manufacturer ID: 1e
> OEM: ffff
> Name: MMC
> Tran Speed: 52000000
> Rd Block Len: 512
> MMC version 4.0
> High Capacity: No
> Capacity: 1.9 GiB
> Bus Width: 12-bit
> 
> Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescalecom>
> CC: Andy Fleming <afleming@gmail.com>
> CC: Marek Vasut <marex@denx.de>
> ---
>  drivers/mmc/fsl_esdhc.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c
> index 3f8d30d..7b83dd2 100644
> --- a/drivers/mmc/fsl_esdhc.c
> +++ b/drivers/mmc/fsl_esdhc.c
> @@ -577,7 +577,7 @@ int fsl_esdhc_initialize(bd_t *bis, struct
> fsl_esdhc_cfg *cfg) return -1;
>  	}
> 
> -	mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT;
> +	mmc->host_caps = MMC_MODE_4BIT;
> 
>  	if (caps & ESDHC_HOSTCAPBLT_HSS)
>  		mmc->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;

Best regards,
Marek Vasut