Re: [PATCH v4 08/11] mtd: brcmnand: add BCM63138 support

[Arnd Bergmann <arnd@arndb.de>]

On Tuesday 12 May 2015 17:53:41 Brian Norris wrote:
> +static bool bcm63138_nand_intc_ack(struct brcmnand_soc *soc)
> +{
> +       struct bcm63138_nand_soc_priv *priv = soc->priv;
> +       void __iomem *mmio = priv->base + BCM63138_NAND_INT_STATUS;
> +       u32 val = brcmnand_readl(mmio);
> +
> +       if (val & BCM63138_CTLRDY) {
> +               brcmnand_writel(val & ~BCM63138_CTLRDY, mmio);
> +               return true;
> +       }
> +
> +       return false;
> +}
...
> +static int bcm63138_nand_probe(struct platform_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct bcm63138_nand_soc_priv *priv;
> +       struct brcmnand_soc *soc;
> +       struct resource *res;
> +
> +       soc = devm_kzalloc(dev, sizeof(*soc), GFP_KERNEL);
> +       if (!soc)
> +               return -ENOMEM;
> +
> +       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +       if (!priv)
> +               return -ENOMEM;
> +

This is a slightly unconventional method of doing the abstraction.
For consistency with a lot of other drivers, I'd do it like this:

struct bcm63138_controller {
	void __iomem *base;
	brcmnand_controller parent;
};

static bool bcm63138_nand_intc_ack(struct brcmnand_controller *parent)
{
	struct bcm63138_controller *controller;
	controller = container_of(parent, struct brcmnand_controller, parent);

	...
}

static int bcm63138_nand_probe(...)
{
	struct bcm63138_controller *controller;

	controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL);
	...
	return brcmnand_probe(pdev, &controller->parent);
}

This also simplifies the probe() functions and means less pointer chasing.

	Arnd