lkml.org 
[lkml]   [2013]   [Apr]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v2 2/8] mtd: add a helper to get the supported features for ONFI nand
From
On Mon, Apr 22, 2013 at 12:47 AM, Huang Shijie <b32955@freescale.com> wrote:
> From: Huang Shijie <shijie8@gmail.com>
>
> add a helper to get the supported features for ONFI nand.
> Also add the neccessary macros.
>
> Signed-off-by: Huang Shijie <b32955@freescale.com>
> ---
> include/linux/mtd/nand.h | 13 +++++++++++++
> 1 files changed, 13 insertions(+), 0 deletions(-)
>
> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
> index 210bf36..122322c 100644
> --- a/include/linux/mtd/nand.h
> +++ b/include/linux/mtd/nand.h
> @@ -202,6 +202,11 @@ typedef enum {
> /* Keep gcc happy */
> struct nand_chip;
>
> +/* ONFI features */
> +#define ONFI_FEATURE_16_BIT_BUS (1 << 0)
> +#define ONFI_FEATURE_EXT_PARAM_PAGE (1 << 7)
> +#define ONFI_FEATURE_UNKNOWN (1 << 15)

Where did you get the UNKNOWN field from? Bit 15 looks like a reserved
field (in ONFI 3.1, at least) and certainly does *not* represent a
null value. Instead, I think it does not need a macro at all, and we
can just use 0 for non-ONFI chips.

> /* ONFI timing mode, used in both asynchronous and synchronous mode */
> #define ONFI_TIMING_MODE_0 (1 << 0)
> #define ONFI_TIMING_MODE_1 (1 << 1)
> @@ -750,6 +755,14 @@ struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
> return chip->priv;
> }
>
> +/* return the supported features. */
> +static inline int onfi_feature(struct nand_chip *chip)
> +{
> + if (!chip->onfi_version)
> + return ONFI_FEATURE_UNKNOWN;

As noted above, just this macro is incorrect.

> + return le16_to_cpu(chip->onfi_params.features);

Just make the whole function:

return chip->onfi_version ? le16_to_cpu(chip->onfi_params.features) : 0;

It is up to the caller to ensure that they don't rely on the returned
value for non-ONFI chips.

> +}
> +
> /* return the supported asynchronous timing mode. */
> static inline int onfi_get_async_timing_mode(struct nand_chip *chip)
> {

Brian


\
 
 \ /
  Last update: 2013-04-22 23:21    [W:0.114 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site