irqchip: crossbar: Return proper error value

crossbar_of_init always returns -ENOMEM in case of errors.
There can be other causes of failure like invalid data from
DT. So return a appropriate error value for that case.

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Sricharan R <r.sricharan@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Link: https://lkml.kernel.org/r/1403766634-18543-10-git-send-email-r.sricharan@ti.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

drivers/irqchip/irq-crossbar.c

@@ -129,19 +129,25 @@ static const struct irq_domain_ops routable_irq_domain_ops = {
 
 static int __init crossbar_of_init(struct device_node *node)
 {
-	int i, size, max, reserved = 0, entry;
+	int i, size, max = 0, reserved = 0, entry;
 	const __be32 *irqsr;
+	int ret = -ENOMEM;
 
 	cb = kzalloc(sizeof(*cb), GFP_KERNEL);
 
 	if (!cb)
-		return -ENOMEM;
+		return ret;
 
 	cb->crossbar_base = of_iomap(node, 0);
 	if (!cb->crossbar_base)
 		goto err1;
 
 	of_property_read_u32(node, "ti,max-irqs", &max);
+	if (!max) {
+		pr_err("missing 'ti,max-irqs' property\n");
+		ret = -EINVAL;
+		goto err2;
+	}
 	cb->irq_map = kcalloc(max, sizeof(int), GFP_KERNEL);
 	if (!cb->irq_map)
 		goto err2;
@@ -162,6 +168,7 @@ static int __init crossbar_of_init(struct device_node *node)
 						   i, &entry);
 			if (entry > max) {
 				pr_err("Invalid reserved entry\n");
+				ret = -EINVAL;
 				goto err3;
 			}
 			cb->irq_map[entry] = IRQ_RESERVED;
@@ -205,6 +212,7 @@ static int __init crossbar_of_init(struct device_node *node)
 		break;
 	default:
 		pr_err("Invalid reg-size property\n");
+		ret = -EINVAL;
 		goto err4;
 		break;
 	}
@@ -243,7 +251,7 @@ static int __init crossbar_of_init(struct device_node *node)
 	iounmap(cb->crossbar_base);
 err1:
 	kfree(cb);
-	return -ENOMEM;
+	return ret;
 }
 
 static const struct of_device_id crossbar_match[] __initconst = {