Thanks a lot for the review and comments.

This patch was derived from our old mmc driver code base, which was based on 
kernel 3.10 and did not implemented the mmc_shutdown() callback in mmc.c yet.
So it added shutdown callback in drivers/mmc/card/block.c to fix data 
corruption issue observed at that time.

Since flush eMMC cache in mmc_shutdown() callback is better than in 
mmc_blk_shutdown(), I think my patch is not needed for current upstream mmc 
driver any more.
Please ignore it :-)

Thanks.

Regards,
Yunpeng

-----Original Message-----
From: Jaehoon Chung [mailto:jh80.ch...@samsung.com] 
Sent: Monday, July 14, 2014 5:51 PM
To: Gao, Yunpeng; linux-mmc@vger.kernel.org
Subject: Re: [PATCH] mmc: blk: add emmc cache flush in shutdown callback

Hi,

On 07/14/2014 06:34 PM, Yunpeng Gao wrote:
> If eMMC Cache feature enabled, we'd better flush eMMC cache in the 
> shutdown callback. Otherwise data corruption issue may be observed.

I knew mmc_flush_cache() is called into mmc_shutdown() (driver/mmc/core/mmc.c) 
Which data corruption is occurred? Could you explain more?

Best Regards,
Jaehoon Chung 

> 
> Signed-off-by: Yunpeng Gao <yunpeng....@intel.com>
> ---
>  drivers/mmc/card/block.c |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 
> 452782b..8a4010e 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -2509,6 +2509,10 @@ static int _mmc_blk_suspend(struct mmc_card 
> *card)  static void mmc_blk_shutdown(struct mmc_card *card)  {
>       _mmc_blk_suspend(card);
> +
> +     mmc_claim_host(card->host);
> +     mmc_flush_cache(card);
> +     mmc_release_host(card->host);
>  }
>  
>  #ifdef CONFIG_PM
> 

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