[PATCH v1 5/7] mtd: fsl-quadspi: get the dummy cycles for DDR Quad read from the DT property

Marek Vasut marex at denx.de
Wed Apr 23 12:48:50 PDT 2014


On Wednesday, April 23, 2014 at 12:16:53 PM, Huang Shijie wrote:
> Check the "spi-nor,ddr-quad-read-dummy" DT property to get the
> dummy cycles for DDR quad read.
> 
> Signed-off-by: Huang Shijie <b32955 at freescale.com>
> ---
>  drivers/mtd/spi-nor/fsl-quadspi.c |    7 +++++++
>  1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c
> b/drivers/mtd/spi-nor/fsl-quadspi.c index 8d659a2..15bdeb9 100644
> --- a/drivers/mtd/spi-nor/fsl-quadspi.c
> +++ b/drivers/mtd/spi-nor/fsl-quadspi.c
> @@ -883,6 +883,7 @@ static int fsl_qspi_probe(struct platform_device *pdev)
>  	for_each_available_child_of_node(dev->of_node, np) {
>  		const struct spi_device_id *id;
>  		char modalias[40];
> +		u32 dummy = 0;
> 
>  		/* skip the holes */
>  		if (!has_second_chip)
> @@ -918,6 +919,12 @@ static int fsl_qspi_probe(struct platform_device
> *pdev) if (ret < 0)
>  			goto map_failed;
> 
> +		/* Set the dummy cycles for the DDR Quad Read */
> +		ret = of_property_read_u32(np, "spi-nor,ddr-quad-read-dummy",
> +				&dummy);
> +		if (!ret && dummy > 0 && dummy < 8)
> +			nor->read_dummy = dummy;

Is there any reason for the upper limit on number of dummy cycles ?

Best regards,
Marek Vasut



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