[PATCH] mmc: dw_mmc: fix 32bit little-endian access of des1 field

[Shawn Lin]

Hi Ben,

On 2016-6-7 21:37, Ben Dooks wrote:
> The IDMAC_SET_BUFFER1_SIZE() macro modifies des1, but does
> not check if the value being passed is big or little endian
> desptire the des1 field being marked as __le32.

Looks good.

Reviewed-by: Shawn Lin <shawn.lin at rock-chips.com>

Test on Rockchip platform, so

Tested-by: Shawn Lin <shawn.lin at rock-chips.com>

> Fix the issue by ensuring the values are changed from the
> cpu endian to the descriptor endian by using cpu_to_le32.
>
> Spotted whilst doing big endian conversion work on Exynos,
> and stops the mmc worker thread from stalling.
>
> Signed-off-by: Ben Dooks <ben.dooks at codethink.co.uk>
> ---
> Cc: Matthew Leach <matt.leach at codethink.co.uk>
> Cc: Jaehoon Chung <jh80.chung at samsung.com>
> Cc: Ulf Hansson <ulf.hansson at linaro.org>
> Cc: linux-mmc at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> ---
>   drivers/mmc/host/dw_mmc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 2cc6123..544397e 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -92,7 +92,7 @@ struct idmac_desc {
>   
>   	__le32		des1;	/* Buffer sizes */
>   #define IDMAC_SET_BUFFER1_SIZE(d, s) \
> -	((d)->des1 = ((d)->des1 & 0x03ffe000) | ((s) & 0x1fff))
> +	((d)->des1 = ((d)->des1 & cpu_to_le32(0x03ffe000)) | (cpu_to_le32((s) & 0x1fff)))
>   
>   	__le32		des2;	/* buffer 1 physical address */
>