2014-07-29 13:26:51

by Raphael Poggi

Subject: [PATCH] mtd: atmel_nand: increase chip_delay

Some nand with 8k page size like Micron MT29F32G08ABAAAWP need more than 20us.

Signed-off-by: Raphaël Poggi <[email protected]>
---
drivers/mtd/nand/atmel_nand.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index e321c56..77bd877 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -2099,7 +2099,7 @@ static int atmel_nand_probe(struct platform_device *pdev)
}

nand_chip->ecc.mode = host->board.ecc_mode;
- nand_chip->chip_delay = 20; /* 20us command delay time */
+ nand_chip->chip_delay = 40; /* 40us command delay time */

if (host->board.bus_width_16) /* 16-bit bus width */
nand_chip->options |= NAND_BUSWIDTH_16;
--
1.7.9.5

2014-07-30 09:37:05

by Josh Wu

Subject: Re: [PATCH] mtd: atmel_nand: increase chip_delay

Hi, Raphael

On 7/29/2014 9:27 PM, Raphael Poggi wrote:
> Some nand with 8k page size like Micron MT29F32G08ABAAAWP need more than 20us.
>
> Signed-off-by: Raphaël Poggi <[email protected]>
> ---
> drivers/mtd/nand/atmel_nand.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
> index e321c56..77bd877 100644
> --- a/drivers/mtd/nand/atmel_nand.c
> +++ b/drivers/mtd/nand/atmel_nand.c
> @@ -2099,7 +2099,7 @@ static int atmel_nand_probe(struct platform_device *pdev)
> }
>
> nand_chip->ecc.mode = host->board.ecc_mode;
> - nand_chip->chip_delay = 20; /* 20us command delay time */
> + nand_chip->chip_delay = 40; /* 40us command delay time */
>
> if (host->board.bus_width_16) /* 16-bit bus width */
> nand_chip->options |= NAND_BUSWIDTH_16;

I just post a patch [1] days ago which does almost the same thing to
support 4k-page nand flash.
personally I am fine with your patch.

Brain, you only need to take care this patch. And drop my patch [1].

[1] http://patchwork.ozlabs.org/patch/372406/

Thanks.
Best Regards,
Josh Wu