Re: [PATCH v5 2/2] Ethernet driver for the WIZnet W5100 chip

[Mark Brown <broonie@opensource.wolfsonmicro.com>]

On Fri, Mar 30, 2012 at 01:00:06PM +0600, Mike Sinkovsky wrote:

> +config WIZNET_W5100
> +	tristate "WIZnet W5100 Ethernet support"
> +	depends on ARM || BLACKFIN

What are the architecture dependencies here?

> +static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
> +{
> +	struct net_device *ndev = ndev_instance;
> +	struct w5100_priv *priv = netdev_priv(ndev);
> +
> +	int ir = w5100_read(priv, W5100_S0_IR);
> +	w5100_write(priv, W5100_S0_IR, ir);
> +
> +	if (ir & S0_IR_RECV) {
> +		if (napi_schedule_prep(&priv->napi)) {
> +			w5100_write(priv, W5100_IMR, 0);
> +			mmiowb();
> +			__napi_schedule(&priv->napi);
> +		}
> +	}
> +
> +	if (ir & S0_IR_SENDOK) {
> +		if (unlikely(netif_queue_stopped(ndev)))
> +			netif_wake_queue(ndev);
> +	}
> +
> +	return IRQ_HANDLED;

This unconditionally acknowledges the interrupt even if one wasn't
reported by the device.

> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +	ret = devm_request_irq(&pdev->dev, irq, w5100_interrupt,
> +			       IRQ_TYPE_LEVEL_LOW, name, ndev);
> +	if (ret < 0)
> +		return ret;
> +	priv->irq = irq;
> +
> +	link = platform_get_resource(pdev, IORESOURCE_IO, 0);
> +	if (!link) {
> +		priv->link_gpio = -1;

This is rather an abuse of the resource API and will run into trouble on
device tree based systems.  You should use platform data for non-DT
systems.

> +		if (request_irq(priv->link_irq, w5100_detect_link,
> +				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
> +				link_name, priv->ndev) < 0)

Suggest using request_any_context_irq() to increase the range of
supported interrupt controllers.

> +err_register:
> +	free_netdev(ndev);
> +	platform_set_drvdata(pdev, NULL);
> +	dev_info(&pdev->dev, "probe failed (%d)\n", err);

This will be done for you by the driver core.