Subject: Re: [PATCH net-next 2/4] net: dsa: mt7530: add interrupt support

From: Florian Fainelli <[email-masked]>
Date: Thu, 29 Apr 2021 16:39:36 -0700

On 4/28/2021 11:21 PM, DENG Qingfang wrote:
> Add support for MT7530 interrupt controller to handle internal PHYs.
> In order to assign an IRQ number to each PHY, the registration of MDIO bus
> is also done in this driver.
> 
> Signed-off-by: DENG Qingfang <[email-masked]>
> ---

[snip]

> +static int
> +mt7530_setup_irq(struct mt7530_priv *priv)
> +{
> +	struct device *dev = priv->dev;
> +	struct device_node *np = dev->of_node;
> +	int ret;
> +
> +	if (!of_property_read_bool(np, "interrupt-controller")) {
> +		dev_info(dev, "no interrupt support\n");
> +		return 0;
> +	}
> +
> +	priv->irq = of_irq_get(np, 0);

Using platform_get_irq() may be a bit nicer to avoid using too many
OF-centric APIs, but this does not have to be changed right now.
Likewise for the interrupt-controller above.

> +	if (priv->irq <= 0) {
> +		dev_err(dev, "failed to get parent IRQ: %d\n", priv->irq);
> +		return priv->irq ? : -EINVAL;
> +	}
> +
> +	priv->irq_domain = irq_domain_add_linear(np, MT7530_NUM_PHYS,
> +						 &mt7530_irq_domain_ops, priv);
> +	if (!priv->irq_domain) {
> +		dev_err(dev, "failed to create IRQ domain\n");
> +		return -ENOMEM;
> +	}
> +
> +	/* This register must be set for MT7530 to properly fire interrupts */
> +	if (priv->id != ID_MT7531)
> +		mt7530_set(priv, MT7530_TOP_SIG_CTRL, TOP_SIG_CTRL_NORMAL);
> +
> +	ret = request_threaded_irq(priv->irq, NULL, mt7530_irq_thread_fn,
> +				   IRQF_ONESHOT, KBUILD_MODNAME, priv);

Maybe dev_name() would be more unique in case a system happens to have
more switches in the future so you can easily differentiate them.

> +	if (ret) {

Can you call mt7530_free_irq() to avoid the error repetition?

> +		irq_domain_remove(priv->irq_domain);
> +		dev_err(dev, "failed to request IRQ: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void
> +mt7530_free_mdio_irq(struct mt7530_priv *priv)
> +{
> +	int p;
> +
> +	for (p = 0; p < MT7530_NUM_PHYS; p++) {
> +		if (BIT(p) & priv->ds->phys_mii_mask) {
> +			unsigned int irq;
> +
> +			irq = irq_find_mapping(priv->irq_domain, p);
> +			irq_dispose_mapping(irq);
> +		}
> +	}
> +}
> +
> +static void
> +mt7530_free_irq_common(struct mt7530_priv *priv)
> +{
> +	free_irq(priv->irq, priv);
> +	irq_domain_remove(priv->irq_domain);
> +}
> +
> +static void
> +mt7530_free_irq(struct mt7530_priv *priv)
> +{
> +	mt7530_free_mdio_irq(priv);
> +	mt7530_free_irq_common(priv);
> +}
> +
> +static int
> +mt7530_setup_mdio(struct mt7530_priv *priv)
> +{
> +	struct dsa_switch *ds = priv->ds;
> +	struct device *dev = priv->dev;
> +	struct mii_bus *bus;
> +	static int idx;
> +	int ret;
> +
> +	bus = devm_mdiobus_alloc(dev);
> +	if (!bus)
> +		return -ENOMEM;
> +
> +	ds->slave_mii_bus = bus;
> +	bus->priv = priv;
> +	bus->name = KBUILD_MODNAME "-mii";
> +	snprintf(bus->id, MII_BUS_ID_SIZE, KBUILD_MODNAME "-%d", idx++);

Likewise using dev_name() here would provide an unique name in case you
have multiple switches.

Feel free to address my comments later, they do not seem to be blocking:

Reviewed-by: Florian Fainelli <[email-masked]>
-- 
Florian