Re: [PATCH 2/2] mtd: spi-nor-core: Add fixups for Spansion S25FL256L

[Pratyush Yadav <p.yadav@ti.com>]

On 08/09/21 05:47PM, tkuw584924@gmail.com wrote:
> From: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
> 
> The S25FL256L is 32MB NOR Flash that does not support Bank Address
> Register. This fixup is activated if CONFIG_SPI_FLASH_BAR is enabled and
> returns ENOTSUPP in setup() hook to avoid further ops.
> 
> Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
> ---
>  drivers/mtd/spi/spi-nor-core.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
> index d5d905fa5a..4940b35682 100644
> --- a/drivers/mtd/spi/spi-nor-core.c
> +++ b/drivers/mtd/spi/spi-nor-core.c
> @@ -3222,6 +3222,23 @@ static struct spi_nor_fixups s25hx_t_fixups = {
>  	.post_bfpt = s25hx_t_post_bfpt_fixup,
>  	.post_sfdp = s25hx_t_post_sfdp_fixup,
>  };
> +
> +#ifdef CONFIG_SPI_FLASH_BAR
> +static int s25fl256l_setup(struct spi_nor *nor, const struct flash_info *info,
> +			   const struct spi_nor_flash_parameter *params)
> +{
> +	return -ENOTSUPP; /* Bank Address Register is not supported */

I am not very familiar with BAR. Can you please explain what would 
happen if we don't do this?

> +}
> +
> +static void s25fl256l_default_init(struct spi_nor *nor)
> +{
> +	nor->setup = s25fl256l_setup;
> +}
> +
> +static struct spi_nor_fixups s25fl256l_fixups = {
> +	.default_init = s25fl256l_default_init,
> +};
> +#endif
>  #endif
>  
>  #ifdef CONFIG_SPI_FLASH_S28HS512T
> @@ -3644,6 +3661,10 @@ void spi_nor_set_fixups(struct spi_nor *nor)
>  			break;
>  		}
>  	}
> +#ifdef CONFIG_SPI_FLASH_BAR

We should avoid using #ifdef as much as possible. Change this to

  if (CONFIG_IS_ENABLED(SPI_FLASH_BAR) && !strcmp())

> +	if (!strcmp(nor->info->name, "s25fl256l"))
> +		nor->fixups = &s25fl256l_fixups;
> +#endif

*sigh* we really need to find a better way to specify fixups. Let me see 
if I can figure something out. In the meantime, this should be fine.

>  #endif
>  
>  #ifdef CONFIG_SPI_FLASH_S28HS512T
> -- 
> 2.25.1
> 

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.