diff --git a/drivers/message/i2o/driver.c b/drivers/message/i2o/driver.c
index d330e4e..a3ee179 100644
--- a/drivers/message/i2o/driver.c
+++ b/drivers/message/i2o/driver.c
@@ -20,6 +20,7 @@
 #include <linux/workqueue.h>
 #include <linux/string.h>
 #include <linux/slab.h>
+#include <linux/log2.h>
 #include "core.h"
 
 #define OSM_NAME	"i2o"
@@ -260,7 +261,7 @@
 	int i;
 	struct i2o_driver *drv;
 
-	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
+	for (i = 0; i < i2o_max_drivers; i++) {
 		drv = i2o_drivers[i];
 
 		if (drv)
@@ -280,7 +281,7 @@
 	int i;
 	struct i2o_driver *drv;
 
-	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
+	for (i = 0; i < i2o_max_drivers; i++) {
 		drv = i2o_drivers[i];
 
 		if (drv)
@@ -299,7 +300,7 @@
 	int i;
 	struct i2o_driver *drv;
 
-	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
+	for (i = 0; i < i2o_max_drivers; i++) {
 		drv = i2o_drivers[i];
 
 		if (drv)
@@ -318,7 +319,7 @@
 	int i;
 	struct i2o_driver *drv;
 
-	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
+	for (i = 0; i < i2o_max_drivers; i++) {
 		drv = i2o_drivers[i];
 
 		if (drv)
@@ -340,8 +341,7 @@
 	spin_lock_init(&i2o_drivers_lock);
 
 	if ((i2o_max_drivers < 2) || (i2o_max_drivers > 64) ||
-	    ((i2o_max_drivers ^ (i2o_max_drivers - 1)) !=
-	     (2 * i2o_max_drivers - 1))) {
+	    !is_power_of_2(i2o_max_drivers)) {
 		osm_warn("max_drivers set to %d, but must be >=2 and <= 64 and "
 			 "a power of 2\n", i2o_max_drivers);
 		i2o_max_drivers = I2O_MAX_DRIVERS;
@@ -349,7 +349,7 @@
 	osm_info("max drivers = %d\n", i2o_max_drivers);
 
 	i2o_drivers =
-	    kzalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL);
+	    kcalloc(i2o_max_drivers, sizeof(*i2o_drivers), GFP_KERNEL);
 	if (!i2o_drivers)
 		return -ENOMEM;