[U-Boot] [PATCH] mmc: Handle switch error status bit in MMC card status

[Pantelis Antoniou]

Hi Andrew,

In general looks good; only a small nag.

On Mar 24, 2014, at 9:39 AM, Andrew Gabbasov wrote:

> MMC switch command for unsupported feature (e.g. bus width) sets a switch
> error bit in card status. This bit should be checked, and, if it's set,
> no access with new controller settings should be performed.
> 
> Signed-off-by: Andrew Gabbasov <andrew_gabbasov at mentor.com>
> ---
> drivers/mmc/mmc.c |    4 +++-
> include/mmc.h     |    2 ++
> 2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
> index 8ab0bc9..16105bc 100644
> --- a/drivers/mmc/mmc.c
> +++ b/drivers/mmc/mmc.c
> @@ -155,6 +155,8 @@ int mmc_send_status(struct mmc *mmc, int timeout)
> #endif
> 		return TIMEOUT;
> 	}
> +	if (cmd.response[0] & MMC_STATUS_SWITCH_ERROR)
> +		return SWITCH_ERR;
> 
> 	return 0;
> }
> @@ -505,7 +507,7 @@ static int mmc_change_freq(struct mmc *mmc)
> 	err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, 1);
> 
> 	if (err)
> -		return err;
> +		return ((err == SWITCH_ERR) ? 0 : err);
> 

Change to:

	return err == SWITCH_ERR ? 0 : err;

No need for parentheses.

> 	/* Now check to see that it worked */
> 	err = mmc_send_ext_csd(mmc, ext_csd);
> diff --git a/include/mmc.h b/include/mmc.h
> index e95a237..d5833f8 100644
> --- a/include/mmc.h
> +++ b/include/mmc.h
> @@ -53,6 +53,7 @@
> #define COMM_ERR		-18 /* Communications Error */
> #define TIMEOUT			-19
> #define IN_PROGRESS		-20 /* operation is in progress */
> +#define SWITCH_ERR		-21 /* Card reports failure to switch mode */
> 
> #define MMC_CMD_GO_IDLE_STATE		0
> #define MMC_CMD_SEND_OP_COND		1
> @@ -108,6 +109,7 @@
> #define SECURE_ERASE		0x80000000
> 
> #define MMC_STATUS_MASK		(~0x0206BF7F)
> +#define MMC_STATUS_SWITCH_ERROR	(1 << 7)
> #define MMC_STATUS_RDY_FOR_DATA (1 << 8)
> #define MMC_STATUS_CURR_STATE	(0xf << 9)
> #define MMC_STATUS_ERROR	(1 << 19)
> -- 
> 1.7.10.4

Regards

-- Pantelis