[PATCH] mtd: nand: Do not automatically set SUBPAGE_READ flag

[Sascha Hauer]

Hi Tjalling,

On Fri, Feb 21, 2014 at 04:23:07PM +0100, Hattink, Tjalling [FINT] wrote:
> The default nand_read_subpage implementation returns -ENOSUPP, so if you
> use a large nand chip without a specific read_subpage implementation the
> read operations will always fail.
> 
> This functionaliy can be restored when a proper nand_read_subpage is
> implemented for the default driver.
> 
> Signed-off-by: Tjalling Hattink <t.hattink at fugro.nl>
> ---
>  drivers/mtd/nand/nand_base.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index 54d8ba3..bfd695b 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -3562,10 +3562,6 @@ int nand_scan_tail(struct mtd_info *mtd)
>         /* Invalidate the pagebuffer reference */
>         chip->pagebuf = -1;
>  
> -       /* Large page NAND with SOFT_ECC should support subpage reads */
> -       if ((chip->ecc.mode == NAND_ECC_SOFT) && (chip->page_shift > 9))
> -               chip->options |= NAND_SUBPAGE_READ;
> -

Only barebox nand_read_subpage returns -ENOSUPP. The kernel has a
default implementation. Wouldn't it be possible (and better) to just
remove the return -ENOSUPP from nand_read_subpage and use the code which
we already have?

Sascha


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