[PATCH] mtd: core: print error code if registering NVMEM fails

[Miquel Raynal]

Hi Rafał,

zajec5 at gmail.com wrote on Fri, 17 Mar 2023 08:47:36 +0100:

> From: Rafał Miłecki <rafal at milecki.pl>
> 
> It's a common practice that helps debugging problems.

Totally agree. I actually sent a patch to avoid the error message
upon EPROBE_DEFER which has the side effect of printing the error
(thanks to the use of dev_err_probe()):

https://lore.kernel.org/linux-mtd/20230307192506.439532-1-miquel.raynal@bootlin.com/

> Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
> ---
>  drivers/mtd/mtdcore.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index 83a22566a8ce..8303ce62c751 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -539,7 +539,8 @@ static int mtd_nvmem_add(struct mtd_info *mtd)
>  		if (PTR_ERR(mtd->nvmem) == -EOPNOTSUPP) {
>  			mtd->nvmem = NULL;
>  		} else {
> -			dev_err(&mtd->dev, "Failed to register NVMEM device\n");
> +			dev_err(&mtd->dev, "Failed to register NVMEM device: %ld\n",
> +				PTR_ERR(mtd->nvmem));
>  			return PTR_ERR(mtd->nvmem);
>  		}
>  	}


Thanks,
Miquèl