diff --git a/feed/app/switch/src/switch_753x.c b/feed/app/switch/src/switch_753x.c
index 6936f6a..9218e57 100644
--- a/feed/app/switch/src/switch_753x.c
+++ b/feed/app/switch/src/switch_753x.c
@@ -8,6 +8,7 @@
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <linux/if.h>
+#include <errno.h>
 
 #include "switch_netlink.h"
 #include "switch_ioctl.h"
@@ -427,27 +428,39 @@
 {
 	unsigned int val;
 	unsigned int off;
+	char *endptr;
 	int i, j;
 
 	if (!strncmp(argv[len - 3], "reg", 4)) {
 		if (argv[len - 2][0] == 'r') {
-			off = strtoul(argv[len - 1], NULL, 16);
+			errno = 0;
+			off = strtoul(argv[len - 1], &endptr, 16);
+			if (errno != 0 || *endptr != '\0')
+				goto error;
 			reg_read(off, &val);
 			printf(" Read reg=%x, value=%x\n", off, val);
 		} else if (argv[len - 2][0] == 'w') {
-			off = strtoul(argv[len - 1], NULL, 16);
+			errno = 0;
+			off = strtoul(argv[len - 1], &endptr, 16);
+			if (errno != 0 || *endptr != '\0')
+				goto error;
 			if (argc != len + 1)
 				usage(argv[0]);
-			val = strtoul(argv[len], NULL, 16);
+			errno = 0;
+			val = strtoul(argv[len], &endptr, 16);
+			if (errno != 0 || *endptr != '\0')
+				goto error;
 			reg_write(off, val);
 			printf(" Write reg=%x, value=%x\n", off, val);
 		} else if (argv[len - 2][0] == 'd') {
-			off = strtoul(argv[len - 1], NULL, 16);
+			errno = 0;
+			off = strtoul(argv[len - 1], &endptr, 16);
+			if (errno != 0 || *endptr != '\0')
+				goto error;
 			for (i = 0; i < 16; i++) {
 				printf("0x%08x: ", off + 0x10 * i);
 				for (j = 0; j < 4; j++) {
-					reg_read(off + i * 0x10 + j * 0x4,
-						 &val);
+					reg_read(off + i * 0x10 + j * 0x4, &val);
 					printf(" 0x%08x", val);
 				}
 				printf("\n");
@@ -456,6 +469,9 @@
 			usage(argv[0]);
 	} else
 		usage(argv[0]);
+	return;
+error:
+	printf("Error: string converting\n");
 }
 
 static int get_chip_name()
@@ -622,7 +638,7 @@
 
 int main(int argc, char *argv[])
 {
-	int err;
+	int err = -EINVAL;
 
 	attres = (struct mt753x_attr *)malloc(sizeof(struct mt753x_attr));
 	if (attres == NULL) {
diff --git a/feed/app/switch/src/switch_netlink.c b/feed/app/switch/src/switch_netlink.c
index 397ebe5..f6f5fb0 100644
--- a/feed/app/switch/src/switch_netlink.c
+++ b/feed/app/switch/src/switch_netlink.c
@@ -44,7 +44,7 @@
 			    nla_get_string(attrs[MT753X_ATTR_TYPE_MESG]);
 			printf("register switch dev:\n%s", val->dev_info);
 		} else {
-			fprintf(stderr, "ERROR:No switch dev now\n");
+			printf("ERROR:No switch dev now\n");
 			goto done;
 		}
 	} else
@@ -132,7 +132,7 @@
 	/* Allocate an netllink message buffer */
 	msg = nlmsg_alloc();
 	if (!msg) {
-		fprintf(stderr, "Failed to allocate netlink message\n");
+		printf("Failed to allocate netlink message\n");
 		exit(1);
 	}
 	if (!construct) {
@@ -148,7 +148,7 @@
 	if (construct) {
 		err = construct(msg, arg);
 		if (err < 0) {
-			fprintf(stderr, "attributes error\n");
+			printf("attributes error\n");
 			goto nal_put_failure;
 		}
 	}
@@ -156,14 +156,14 @@
 	/* Allocate an new callback handler */
 	callback = nl_cb_alloc(NL_CB_CUSTOM);
 	if (!callback) {
-		fprintf(stderr, "Failed to allocate callback handler\n");
+		printf("Failed to allocate callback handler\n");
 		exit(1);
 	}
 
 	/* Send netlink message */
 	err = nl_send_auto_complete(user_sock, msg);
 	if (err < 0) {
-		fprintf(stderr, "nl_send_auto_complete failied:%d\n", err);
+		printf("nl_send_auto_complete failied:%d\n", err);
 		goto out;
 	}
 	finished = 0;
@@ -218,18 +218,18 @@
 	/* Allocate an new netlink socket */
 	user_sock = nl_socket_alloc();
 	if (!user_sock) {
-		fprintf(stderr, "Failed to create user socket\n");
+		printf("Failed to create user socket\n");
 		goto err;
 	}
 	/* Connetct the genl controller */
 	if (genl_connect(user_sock)) {
-		fprintf(stderr, "Failed to connetct to generic netlink\n");
+		printf("Failed to connetct to generic netlink\n");
 		goto err;
 	}
 	/* Allocate an new nl_cache */
 	ret = genl_ctrl_alloc_cache(user_sock, &cache);
 	if (ret < 0) {
-		fprintf(stderr, "Failed to allocate netlink cache\n");
+		printf("Failed to allocate netlink cache\n");
 		goto err;
 	}
 
@@ -254,7 +254,7 @@
 
 	err = mt753x_request_callback(cmd, list_swdevs, NULL, arg);
 	if (err < 0)
-		fprintf(stderr, "mt753x list dev error\n");
+		printf("mt753x list dev error\n");
 }
 
 static int mt753x_request(struct mt753x_attr *arg, int cmd)
@@ -263,7 +263,7 @@
 
 	err = mt753x_request_callback(cmd, spilt_attrs, construct_attrs, arg);
 	if (err < 0) {
-		fprintf(stderr, "mt753x deal request error\n");
+		printf("mt753x deal request error\n");
 		return err;
 	}
 	return 0;
@@ -279,7 +279,7 @@
 	attr->port_num = port_num;
 	attr->phy_dev = phy_dev;
 	attr->reg = offset;
-	attr->value = -1;
+	attr->value = 0;
 	attr->type = MT753X_ATTR_TYPE_REG;
 
 	switch (op) {