IRQs in i2c-mpc.c

["Jon Smirl" <jonsmirl@gmail.com>]

I'm doing final clean up the i2c open firmware support. What is the
intention of this code? Is it meant for a missing IRQ attribute to
return a zero and not get an IRQ for the device? Does the device
function without an IRQ? If so, it needs a comment explaining things.
Otherwise IRQ of zero should be an error.

	i2c->irq = irq_of_parse_and_map(op->node, 0);
	if (i2c->irq <= 0) {
		result = -ENXIO;
		goto fail_irq;
	}
	
	if (i2c->irq != 0)
		if ((result = request_irq(i2c->irq, mpc_i2c_isr,
					  	IRQF_SHARED, "i2c-mpc", i2c)) < 0) {
			printk(KERN_ERR "i2c-mpc - failed to attach interrupt\n");
			goto fail_irq;
		}

-- 
Jon Smirl
jonsmirl@gmail.com