Re: [PATCH v3 14/32] mtd: spi-nor: Fix retlen handling in sst_write()

[Boris Brezillon]

On Tue, 29 Oct 2019 11:17:10 +0000
<Tudor.Ambarus@xxxxxxxxxxxxx> wrote:

> From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
> 
> In case the write of the first byte failed, retlen was incorrectly
> incremented to *retlen += actual; on the exit path. retlen should be
> incremented when actual data was written to the flash.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>

> ---
>  drivers/mtd/spi-nor/spi-nor.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index bc46b946ac77..889fd77dbe96 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -2667,7 +2667,7 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
>  		size_t *retlen, const u_char *buf)
>  {
>  	struct spi_nor *nor = mtd_to_spi_nor(mtd);
> -	size_t actual;
> +	size_t actual = 0;
>  	int ret;
>  
>  	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
> @@ -2680,9 +2680,8 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
>  
>  	nor->sst_write_second = false;
>  
> -	actual = to % 2;
>  	/* Start write from odd address. */
> -	if (actual) {
> +	if (to % 2) {
>  		nor->program_opcode = SPINOR_OP_BP;
>  
>  		/* write one byte. */
> @@ -2693,8 +2692,10 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
>  		ret = spi_nor_wait_till_ready(nor);
>  		if (ret)
>  			goto sst_write_err;
> +
> +		to++;
> +		actual++;
>  	}
> -	to += actual;
>  
>  	/* Write out most of the data here. */
>  	for (; actual < len - 1; actual += 2) {