Re: [PATCH v4 26/35] mtd: rawnand: atmel: convert driver to nand_scan()

[Boris Brezillon <boris.brezillon@bootlin.com>]

On Fri, 20 Jul 2018 17:15:18 +0200
Miquel Raynal <miquel.raynal@bootlin.com> wrote:

> Two helpers have been added to the core to make ECC-related
> configuration between the detection phase and the final NAND scan. Use
> these hooks and convert the driver to just use nand_scan() instead of
> both nand_scan_ident() and nand_scan_tail().
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  drivers/mtd/nand/raw/atmel/nand-controller.c | 83 ++++++++++++++--------------
>  1 file changed, 40 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c
> index 855cc7729c43..0bc7e2abc885 100644
> --- a/drivers/mtd/nand/raw/atmel/nand-controller.c
> +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c
> @@ -202,7 +202,7 @@ struct atmel_nand_controller_ops {
>  	int (*remove)(struct atmel_nand_controller *nc);
>  	void (*nand_init)(struct atmel_nand_controller *nc,
>  			  struct atmel_nand *nand);
> -	int (*ecc_init)(struct atmel_nand *nand);
> +	int (*ecc_init)(struct nand_chip *chip);
>  	int (*setup_data_interface)(struct atmel_nand *nand, int csline,
>  				    const struct nand_data_interface *conf);
>  };
> @@ -1133,9 +1133,8 @@ static int atmel_nand_pmecc_init(struct nand_chip *chip)
>  	return 0;
>  }
>  
> -static int atmel_nand_ecc_init(struct atmel_nand *nand)
> +static int atmel_nand_ecc_init(struct nand_chip *chip)
>  {
> -	struct nand_chip *chip = &nand->base;
>  	struct atmel_nand_controller *nc;
>  	int ret;
>  
> @@ -1170,12 +1169,11 @@ static int atmel_nand_ecc_init(struct atmel_nand *nand)
>  	return 0;
>  }
>  
> -static int atmel_hsmc_nand_ecc_init(struct atmel_nand *nand)
> +static int atmel_hsmc_nand_ecc_init(struct nand_chip *chip)
>  {
> -	struct nand_chip *chip = &nand->base;
>  	int ret;
>  
> -	ret = atmel_nand_ecc_init(nand);
> +	ret = atmel_nand_ecc_init(chip);
>  	if (ret)
>  		return ret;
>  
> @@ -1558,22 +1556,6 @@ static void atmel_hsmc_nand_init(struct atmel_nand_controller *nc,
>  	chip->select_chip = atmel_hsmc_nand_select_chip;
>  }
>  
> -static int atmel_nand_detect(struct atmel_nand *nand)
> -{
> -	struct nand_chip *chip = &nand->base;
> -	struct mtd_info *mtd = nand_to_mtd(chip);
> -	struct atmel_nand_controller *nc;
> -	int ret;
> -
> -	nc = to_nand_controller(chip->controller);
> -
> -	ret = nand_scan_ident(mtd, nand->numcs, NULL);
> -	if (ret)
> -		dev_err(nc->dev, "nand_scan_ident() failed: %d\n", ret);
> -
> -	return ret;
> -}
> -
>  static int atmel_nand_unregister(struct atmel_nand *nand)
>  {
>  	struct nand_chip *chip = &nand->base;
> @@ -1595,7 +1577,6 @@ static int atmel_nand_register(struct atmel_nand *nand)
>  	struct nand_chip *chip = &nand->base;
>  	struct mtd_info *mtd = nand_to_mtd(chip);
>  	struct atmel_nand_controller *nc;
> -	int ret;
>  
>  	nc = to_nand_controller(chip->controller);
>  
> @@ -1626,21 +1607,6 @@ static int atmel_nand_register(struct atmel_nand *nand)
>  		}
>  	}
>  
> -	ret = nand_scan_tail(mtd);
> -	if (ret) {
> -		dev_err(nc->dev, "nand_scan_tail() failed: %d\n", ret);
> -		return ret;
> -	}
> -
> -	ret = mtd_device_register(mtd, NULL, 0);
> -	if (ret) {
> -		dev_err(nc->dev, "Failed to register mtd device: %d\n", ret);
> -		nand_cleanup(chip);
> -		return ret;
> -	}
> -
> -	list_add_tail(&nand->node, &nc->chips);
> -

You can move all the code in atmel_nand_register() directly in
atmel_nand_controller_add_nand() + rename atmel_nand_unregister() into
atmel_nand_controller_remove_nand(). This should be done in a separate
patch so that the transition to nand_scan() is easier to review.

>  	return 0;
>  }
>  
> @@ -1755,6 +1721,8 @@ static int
>  atmel_nand_controller_add_nand(struct atmel_nand_controller *nc,
>  			       struct atmel_nand *nand)
>  {
> +	struct nand_chip *chip = &nand->base;
> +	struct mtd_info *mtd = nand_to_mtd(chip);
>  	int ret;
>  
>  	/* No card inserted, skip this NAND. */
> @@ -1765,15 +1733,30 @@ atmel_nand_controller_add_nand(struct atmel_nand_controller *nc,
>  
>  	nc->caps->ops->nand_init(nc, nand);
>  
> -	ret = atmel_nand_detect(nand);
> -	if (ret)
> +	ret = nand_scan(mtd, nand->numcs);
> +	if (ret) {
> +		dev_err(nc->dev, "NAND scan failed: %d\n", ret);
>  		return ret;
> +	}
>  
> -	ret = nc->caps->ops->ecc_init(nand);
> +	ret = atmel_nand_register(nand);
>  	if (ret)
> -		return ret;
> +		goto cleanup_nand;
> +
> +	ret = mtd_device_register(mtd, NULL, 0);
> +	if (ret) {
> +		dev_err(nc->dev, "Failed to register mtd device: %d\n", ret);
> +		goto cleanup_nand;
> +	}
> +
> +	list_add_tail(&nand->node, &nc->chips);
> +
> +	return 0;
> +
> +cleanup_nand:
> +	nand_cleanup(chip);
>  
> -	return atmel_nand_register(nand);
> +	return ret;
>  }
>  
>  static int
> @@ -1958,6 +1941,19 @@ static const struct of_device_id atmel_matrix_of_ids[] = {
>  	{ /* sentinel */ },
>  };
>  
> +static int atmel_nand_attach_chip(struct nand_chip *chip)
> +{
> +	struct atmel_nand_controller *nc;
> +
> +	nc = to_nand_controller(chip->controller);
> +
> +	return nc->caps->ops->ecc_init(chip);
> +}
> +
> +static const struct nand_controller_ops atmel_nand_controller_ops = {
> +	.attach_chip = atmel_nand_attach_chip,
> +};
> +
>  static int atmel_nand_controller_init(struct atmel_nand_controller *nc,
>  				struct platform_device *pdev,
>  				const struct atmel_nand_controller_caps *caps)
> @@ -1967,6 +1963,7 @@ static int atmel_nand_controller_init(struct atmel_nand_controller *nc,
>  	int ret;
>  
>  	nand_controller_init(&nc->base);
> +	nc->base.ops = &atmel_nand_controller_ops;
>  	INIT_LIST_HEAD(&nc->chips);
>  	nc->dev = dev;
>  	nc->caps = caps;