Re: [PATCH v3 03/11] mtd: cfi_cmdset_0002: Remove goto statement from do_write_buffer()

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

On Fri, 26 Oct 2018 01:32:11 +0900
Tokunori Ikegami <ikegami@allied-telesis.co.jp> wrote:

> For a maintainability by reducing the goto statement remove it from
> do_write_buffer().

I guess that's a matter of taste, but I don't find this version more
readable than the previous one. Any strong reason to get rid of the
op_done label?

> 
> Signed-off-by: Tokunori Ikegami <ikegami@allied-telesis.co.jp>
> Cc: Fabio Bettoni <fbettoni@gmail.com>
> Co: Hauke Mehrtens <hauke@hauke-m.de>
> Co: Koen Vandeputte <koen.vandeputte@ncentric.com>
> Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
> Cc: Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
> Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
> Cc: linux-mtd@lists.infradead.org
> ---
> Changes since v2:
> - None.
> 
> Changes since v1:
> - Split the patch v1 3/3.
> 
>  drivers/mtd/chips/cfi_cmdset_0002.c | 46 +++++++++++++++--------------
>  1 file changed, 24 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
> index c2e51768a02c..deffafab067e 100644
> --- a/drivers/mtd/chips/cfi_cmdset_0002.c
> +++ b/drivers/mtd/chips/cfi_cmdset_0002.c
> @@ -1884,38 +1884,40 @@ static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
>  
>  		if (chip_good(map, adr, datum)) {
>  			xip_enable(map, chip, adr);
> -			goto op_done;
> +			break;
>  		}
>  
> -		if (time_after(jiffies, timeo))
> +		if (time_after(jiffies, timeo)) {
> +			ret = -EIO;
>  			break;
> +		}
>  
>  		/* Latency issues. Drop the lock, wait a while and retry */
>  		UDELAY(map, chip, adr, 1);
>  	}
>  
> -	/*
> -	 * Recovery from write-buffer programming failures requires
> -	 * the write-to-buffer-reset sequence.  Since the last part
> -	 * of the sequence also works as a normal reset, we can run
> -	 * the same commands regardless of why we are here.
> -	 * See e.g.
> -	 * http://www.spansion.com/Support/Application%20Notes/MirrorBit_Write_Buffer_Prog_Page_Buffer_Read_AN.pdf
> -	 */
> -	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
> -			 cfi->device_type, NULL);
> -	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
> -			 cfi->device_type, NULL);
> -	cfi_send_gen_cmd(0xF0, cfi->addr_unlock1, chip->start, map, cfi,
> -			 cfi->device_type, NULL);
> -	xip_enable(map, chip, adr);
> -	/* FIXME - should have reset delay before continuing */
> +	if (ret) {
> +		/*
> +		 * Recovery from write-buffer programming failures requires
> +		 * the write-to-buffer-reset sequence.  Since the last part
> +		 * of the sequence also works as a normal reset, we can run
> +		 * the same commands regardless of why we are here.
> +		 * See e.g.
> +		 * http://www.spansion.com/Support/Application%20Notes/MirrorBit_Write_Buffer_Prog_Page_Buffer_Read_AN.pdf
> +		 */
> +		cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
> +				 cfi->device_type, NULL);
> +		cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
> +				 cfi->device_type, NULL);
> +		cfi_send_gen_cmd(0xF0, cfi->addr_unlock1, chip->start, map, cfi,
> +				 cfi->device_type, NULL);
> +		xip_enable(map, chip, adr);
> +		/* FIXME - should have reset delay before continuing */
>  
> -	printk(KERN_WARNING "MTD %s(): software timeout, address:0x%.8lx.\n",
> -	       __func__, adr);
> +		printk(KERN_WARNING "MTD %s(): software timeout, address:0x%.8lx.\n",
> +		       __func__, adr);
> +	}
>  
> -	ret = -EIO;
> - op_done:
>  	chip->state = FL_READY;
>  	DISABLE_VPP(map);
>  	put_chip(map, chip, adr);