diff --git a/drivers/macintosh/macio_sysfs.c b/drivers/macintosh/macio_sysfs.c
index 97d22bb..7f7d4ea 100644
--- a/drivers/macintosh/macio_sysfs.c
+++ b/drivers/macintosh/macio_sysfs.c
@@ -39,6 +39,31 @@
 	return length;
 }
 
+static ssize_t modalias_show (struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct of_device *of;
+	char *compat;
+	int cplen;
+	int length;
+
+	of = &to_macio_device (dev)->ofdev;
+	compat = (char *) get_property (of->node, "compatible", &cplen);
+	if (!compat) compat = "", cplen = 1;
+	length = sprintf (buf, "of:N%sT%s", of->node->name, of->node->type);
+	buf += length;
+	while (cplen > 0) {
+		int l;
+		length += sprintf (buf, "C%s", compat);
+		buf += length;
+		l = strlen (compat) + 1;
+		compat += l;
+		cplen -= l;
+	}
+
+	return length;
+}
+
 macio_config_of_attr (name, "%s\n");
 macio_config_of_attr (type, "%s\n");
 
@@ -46,5 +71,6 @@
 	__ATTR_RO(name),
 	__ATTR_RO(type),
 	__ATTR_RO(compatible),
+	__ATTR_RO(modalias),
 	__ATTR_NULL
 };