Re: [PATCH v2 5/6] mtd: spi-nor: simplify spi_nor_get_flash_info()

Tudor Ambarus
2024-04-22T06:41:12Z

On 4/19/24 15:12, Michael Walle wrote:
> Rework spi_nor_get_flash_info() to make it look more straight forward
> and esp. don't return early. The latter is a preparation to check for
> deprecated flashes.
>
> Signed-off-by: Michael Walle <mwalle@kernel.org>
> Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
> ---
> drivers/mtd/spi-nor/core.c | 45 ++++++++++++++++++--------------------
> 1 file changed, 21 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index 4e2ae6642d4c..8e4ae1317870 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -3294,39 +3294,36 @@ static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
> static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
> const char *name)
> {
> - const struct flash_info *info = NULL;
> + const struct flash_info *jinfo = NULL, *info = NULL;
>
> if (name)
> info = spi_nor_match_name(nor, name);
> - /* Try to auto-detect if chip name wasn't specified or not found */
> - if (!info)
> - return spi_nor_detect(nor);
> -
> /*
> - * If caller has specified name of flash model that can normally be
> - * detected using JEDEC, let's verify it.
> + * Auto-detect if chip name wasn't specified or not found, or the chip
> + * has an ID. If the chip supposedly has an ID, we also do an
> + * auto-detection to compare it later.
> */
> - if (name && info->id) {
> - const struct flash_info *jinfo;
> -
> + if (!info || info->id) {
> jinfo = spi_nor_detect(nor);
> - if (IS_ERR(jinfo)) {
> + if (IS_ERR(jinfo))
> return jinfo;
> - } else if (jinfo != info) {

you can remove else if with if (jinfo != info)

> - /*
> - * JEDEC knows better, so overwrite platform ID. We
> - * can't trust partitions any longer, but we'll let
> - * mtd apply them anyway, since some partitions may be
> - * marked read-only, and we don't want to loose that
> - * information, even if it's not 100% accurate.
> - */
> - dev_warn(nor->dev, "found %s, expected %s\n",
> - jinfo->name, info->name);

keep the warning where it was
> - info = jinfo;

move this so that it belongs to if (!info || info->id)
> - }
> }
>

and then return info. Does it work?

if (name)
info = spi_nor_match_name(nor, name);

if (!info || info->id) {
jinfo = spi_nor_detect(nor);
if (IS_ERR(jinfo))
return jinfo;

if (jinfo != info)
dev_warn(();
info = jinfo;
}

return info;

> - return info;
> + /*
> + * If caller has specified name of flash model that can normally be
> + * detected using JEDEC, let's verify it.
> + */
> + if (info && jinfo && jinfo != info)> + dev_warn(nor->dev, "found %s, expected %s\n",
> + jinfo->name, info->name);
> +
> + /*
> + * JEDEC knows better, so overwrite platform ID. We can't trust
> + * partitions any longer, but we'll let mtd apply them anyway, since
> + * some partitions may be marked read-only, and we don't want to loose
> + * that information, even if it's not 100% accurate.
> + */
> + return jinfo ?: info;