Re: [PATCH v3 2/2] soc: Add driver for Freescale Vybrid Platform

[Arnd Bergmann <arnd@arndb.de>]

On Friday 22 May 2015 16:21:54 Sanchayan Maity wrote:
> +#define OCOTP_CFG0_OFFSET      0x00000410
> +#define OCOTP_CFG1_OFFSET      0x00000420
> +#define MSCM_CPxCOUNT_OFFSET   0x0000002C
> +#define MSCM_CPxCFG1_OFFSET    0x00000014
> +#define ROM_REVISION_OFFSET    0x00000080
> +
> +static const struct of_device_id vf610_soc_bus_match[] = {
> +	{ .compatible = "fsl,vf610-mscm-cpucfg", },
> +	{ /* sentinel */ }
> +};
> +
> +static int __init vf610_soc_init(void)
> +{
> +	struct regmap *ocotp_regmap, *mscm_regmap, *rom_regmap;
> +	struct soc_device_attribute *soc_dev_attr;
> +	struct soc_device *soc_dev;
> +	struct device_node *np;
> +	char soc_type[] = "xx0";
> +	u32 cpxcount, cpxcfg1;
> +	u32 soc_id1, soc_id2, rom_rev;
> +	u64 soc_id;
> +	int ret;
> +
> +	np = of_find_matching_node(NULL, vf610_soc_bus_match);
> +	if (!np)
> +		return -ENODEV;
> +

Why not use module_platform_driver() and make this a probe function instead?

> +	ocotp_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-ocotp");
> +	if (IS_ERR(ocotp_regmap)) {
> +		pr_err("regmap lookup for octop failed\n");
> +		return PTR_ERR(ocotp_regmap);
> +	}
> +
> +	mscm_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-mscm-cpucfg");
> +	if (IS_ERR(mscm_regmap)) {
> +		pr_err("regmap lookup for mscm failed");
> +		return PTR_ERR(mscm_regmap);
> +	}
> +
> +	rom_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-ocrom");
> +	if (IS_ERR(rom_regmap)) {
> +		pr_err("regmap lookup for ocrom failed");
> +		return PTR_ERR(rom_regmap);
> +	}

Can you use syscon_regmap_lookup_by_phandle instead, and put the
phandles in the fsl,vf610-mscm-cpucfg node?

Also, I'd argue that the mscm should not be a syscon device at all,
but instead I'd use platform_get_resource()/devm_ioremap_resource()
to get an __iomem pointer.

	Arnd