Re: [PATCH v8 2/2] mtd: spi-nor: Add spi-nor mtd resume handler

[Cyrille Pitchen]

Hi Kamal,

Le 22/08/2017 Ã 22:45, Kamal Dasu a Ãcrit :
> Implemented and populated spi-nor mtd PM handlers for resume ops.
> spi-nor resume op re-initializes spi-nor flash to its probed
> state by calling the newly implemented spi_nor_init() function.
> 
> Signed-off-by: Kamal Dasu <kdasu.kdev@xxxxxxxxx>
> ---
>  drivers/mtd/spi-nor/spi-nor.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index ab98ecff..69164bc 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -1871,6 +1871,19 @@ static int spi_nor_init(struct spi_nor *nor)
>  	return 0;
>  }
>  
> +/* mtd resume handler */
> +static void spi_nor_resume(struct mtd_info *mtd)
> +{
> +	struct spi_nor *nor = mtd_to_spi_nor(mtd);
> +	struct device *dev = nor->dev;
> +	int ret;
> +
> +	/* re-initialize the nor chip */
> +	ret = spi_nor_init(nor);
> +	if (ret)
> +		dev_err(dev, "resume() failed\n");
> +}
> +
>  int spi_nor_scan(struct spi_nor *nor, const char *name,
>  		 const struct spi_nor_hwcaps *hwcaps)
>  {
> @@ -1947,6 +1960,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
>  	mtd->size = params.size;
>  	mtd->_erase = spi_nor_erase;
>  	mtd->_read = spi_nor_read;
> +	mtd->_resume = spi_nor_resume;
>

The series now looks good to me. Just waiting for Marek's
acked-by/reviewed-by to double-check.

Marek: I can't test with the Cadence QSPI controller but based on the
line "mtd->dev.parent = nor->dev;" in spi_nor_scan(), I think this patch
won't conflit with the already PM code in the cadence-quadspi.c driver.

As far as I understand, cqspi_resume() will be called before
mtd_resume() / spi_nor_resume().

Best regards,

Cyrille

>  	/* NOR protection support for STmicro/Micron chips and similar */
>  	if (JEDEC_MFR(info) == SNOR_MFR_MICRON ||
>