diff --git a/feed/mii_mgr/src/mii_mgr.c b/feed/mii_mgr/src/mii_mgr.c
index a22c3e8..8e1ec39 100644
--- a/feed/mii_mgr/src/mii_mgr.c
+++ b/feed/mii_mgr/src/mii_mgr.c
@@ -1,6 +1,8 @@
 #include <errno.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
@@ -17,18 +19,28 @@
 
 #include "mii_mgr.h"
 
+static bool is_silent;
+
+#define INFO(...)			\
+do {					\
+	if (!is_silent) {		\
+		printf(__VA_ARGS__);	\
+	}				\
+} while (0)
+
 void show_usage(void)
 {
-	printf("mii_mgr -g -i [ifname] -p [phy number] -r [register number]\n");
-	printf("  Get: mii_mgr -g -p 3 -r 4\n\n");
-	printf("mii_mgr -s -p [phy number] -r [register number] -v [0xvalue]\n");
-	printf("  Set: mii_mgr -s -p 4 -r 1 -v 0xff11\n");
-	printf("#NOTE: Without -i , eth0 is default ifname!\n");
-	printf("----------------------------------------------------------------------------------------\n");
-	printf("Get: mii_mgr_cl45 -g -p [port number] -d [dev number] -r [register number]\n");
-	printf("Example: mii_mgr_cl45 -g -p 3 -d 0x5 -r 0x4\n\n");
-	printf("Set: mii_mgr_cl45 -s -p [port number] -d [dev number] -r [register number] -v [value]\n");
-	printf("Example: mii_mgr_cl45 -s -p 4 -d 0x6 -r 0x1 -v 0xff11\n\n");
+	INFO("mii_mgr -g -i [ifname] -p [phy number] -r [register number]\n"
+	     "  Get: mii_mgr -g -p 3 -r 4\n\n"
+	     "mii_mgr -s -p [phy number] -r [register number] -v [0xvalue]\n"
+	     "  Set: mii_mgr -s -p 4 -r 1 -v 0xff11\n"
+	     "#NOTE: Without -i , eth0 is default ifname!\n"
+	     " -z: silent mode\n"
+	     "----------------------------------------------------------------------------------------\n"
+	     "Get: mii_mgr_cl45 -g -p [port number] -d [dev number] -r [register number]\n"
+	     "Example: mii_mgr_cl45 -g -p 3 -d 0x5 -r 0x4\n\n"
+	     "Set: mii_mgr_cl45 -s -p [port number] -d [dev number] -r [register number] -v [value]\n"
+	     "Example: mii_mgr_cl45 -s -p 4 -d 0x6 -r 0x1 -v 0xff11\n\n");
 }
 
 static void fill_mii_ioctl(struct mii_ioctl_data *mii, uint16_t phy_id,
@@ -52,18 +64,18 @@
 
 static int __phy_op(char *ifname, uint16_t phy_id, uint16_t reg_num, unsigned int *val, uint16_t cmd, int is_priv)
 {
-        static int sd = -1;
+	static int sd = -1;
 
-        struct ifreq ifr;
-        struct mii_ioctl_data mii;
+	struct ifreq ifr;
+	struct mii_ioctl_data mii;
 	struct mtk_mii_ioctl_data mtk_mii;
-        int err;
+	int err;
 
-        if (sd < 0)
-                sd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (sd < 0)
+		sd = socket(AF_INET, SOCK_DGRAM, 0);
 
-        if (sd < 0)
-                return sd;
+	if (sd < 0)
+		return sd;
 
 	strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
 	ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
@@ -76,9 +88,9 @@
 		ifr.ifr_data = (char *)&mii;
 	}
 
-        err = ioctl(sd, cmd, &ifr);
-        if (err)
-                return -errno;
+	err = ioctl(sd, cmd, &ifr);
+	if (err)
+		return -errno;
 
 	if ((cmd == MTKETH_MII_WRITE) || (cmd == MTKETH_MII_WRITE_CL45) ||
 	    (cmd == SIOCSMIIREG))
@@ -86,7 +98,7 @@
 	else
 		*val = (is_priv) ? mtk_mii.val_out : mii.val_out;
 
-        return 0;
+	return 0;
 }
 
 int main(int argc, char *argv[])
@@ -96,11 +108,10 @@
 	int is_write = 0,is_cl45 = 0;
 	int is_priv = 1;
 	unsigned int port=0, dev=0,reg_num=0,val=0;
-	char ifname[IFNAMSIZ]="eth0";	
+	char ifname[IFNAMSIZ] = "eth0";
 	uint16_t phy_id=0;
 	uint16_t cmd;
 
-
 	if (argc < 6) {
 		show_usage();
 		return 0;
@@ -120,14 +131,14 @@
 			case 'i':
 				strncpy(ifname, optarg, 5);
 				ifname[IFNAMSIZ - 1] = '\0';
-				break;	
+				break;
 			case 'p':
 				port = strtoul(optarg, NULL, 16);
 				if (port > INT_MAX)
 					return -EINVAL;
 				break;
-                        case 'd':				
-                                dev = strtoul(optarg, NULL, 16);
+			case 'd':
+				dev = strtoul(optarg, NULL, 16);
 				if (dev > INT_MAX)
 					return -EINVAL;
 				is_cl45 = 1;
@@ -137,12 +148,14 @@
 				if (reg_num > INT_MAX)
 					return -EINVAL;
 				break;
-
 			case 'v':
 				val = strtoul(optarg, NULL, 16);
 				if (val > INT_MAX)
 					return -EINVAL;
 				break;
+			case 'z':
+				is_silent = true;
+				break;
 			case '?':
 				show_usage();
 				break;
@@ -154,7 +167,7 @@
 	else
 		phy_id = port;
 
-	if(is_write) { 
+	if (is_write) {
 		if (is_priv)
 			cmd = (is_cl45) ? MTKETH_MII_WRITE_CL45 :
 					  MTKETH_MII_WRITE;
@@ -164,10 +177,12 @@
 		__phy_op(ifname,phy_id,reg_num, &val, cmd, is_priv);
 
 		if(is_cl45)
-			printf("Set: port%x dev%Xh_reg%Xh = 0x%04X\n",port, dev, reg_num, val);
+			INFO("Set: port%x dev%Xh_reg%Xh = 0x%04X\n",
+				port, dev, reg_num, val);
 		else
-			printf("Set: phy[%x].reg[%x] = %04x\n",port, reg_num, val);
-	}	
+			INFO("Set: phy[%x].reg[%x] = %04x\n",
+				port, reg_num, val);
+	}
 	else {
 		if (is_priv)
 			cmd = (is_cl45) ? MTKETH_MII_READ_CL45 :
@@ -178,11 +193,12 @@
 		__phy_op(ifname,phy_id,reg_num, &val, cmd, is_priv);
 
 		if(is_cl45)
-			printf("Get: port%x dev%Xh_reg%Xh = 0x%04X\n",port, dev, reg_num, val);
+			INFO("Get: port%x dev%Xh_reg%Xh = 0x%04X\n",
+				port, dev, reg_num, val);
 		else
-			printf("Get: phy[%x].reg[%x] = %04x\n",port, reg_num, val);
-	
+			INFO("Get: phy[%x].reg[%x] = %04x\n",
+				port, reg_num, val);
 	}
 
-	return 0;	
+	return 0;
 }