Re: [PATCH v3 3/3] EDAC: nuvoton: Add NPCM memory controller driver

[Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>]

On 11/03/2022 02:42, Medad CChien wrote:
> Add support for Nuvoton NPCM SoC.
> 
> Signed-off-by: Medad CChien <ctcchien@nuvoton.com>
> ---
>  drivers/edac/Kconfig     |   9 +
>  drivers/edac/Makefile    |   1 +
>  drivers/edac/npcm_edac.c | 714 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 724 insertions(+)
>  create mode 100644 drivers/edac/npcm_edac.c
> 
> diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> index 58ab63642e72..757e1d160640 100644
> --- a/drivers/edac/Kconfig
> +++ b/drivers/edac/Kconfig
> @@ -539,4 +539,13 @@ config EDAC_DMC520
>  	  Support for error detection and correction on the
>  	  SoCs with ARM DMC-520 DRAM controller.
>  
> +config EDAC_NPCM
> +	tristate "Nuvoton NPCM DDR Memory Controller"
> +	depends on ARCH_NPCM

|| COMPILE_TEST
(and test if it compiles)

(...)

> +
> +MODULE_DEVICE_TABLE(of, npcm_edac_of_match);
> +
> +static int npcm_edac_mc_probe(struct platform_device *pdev)
> +{
> +	const struct npcm_edac_platform_data *npcm_chip;
> +	struct device *dev = &pdev->dev;
> +	struct edac_mc_layer layers[1];
> +	const struct of_device_id *id;
> +	struct priv_data *priv_data;
> +	struct mem_ctl_info *mci;
> +	struct resource *res;
> +	void __iomem *reg;
> +	int ret = -ENODEV;
> +	int irq;
> +
> +	id = of_match_device(npcm_edac_of_match, &pdev->dev);
> +	if (!id)
> +		return -ENODEV;

Why do you need it? How such case is even possible?

> +
> +	npcm_chip = of_device_get_match_data(&pdev->dev);
> +	if (!npcm_chip)
> +		return -ENODEV;

I wonder, how is it possible to have here NULL?

Best regards,
Krzysztof