diff --git a/drivers/staging/vt6656/baseband.c b/drivers/staging/vt6656/baseband.c
index e7000bba644a..1d75acaec8f3 100644
--- a/drivers/staging/vt6656/baseband.c
+++ b/drivers/staging/vt6656/baseband.c
@@ -23,6 +23,7 @@
  */
 
 #include <linux/bits.h>
+#include <linux/errno.h>
 #include <linux/kernel.h>
 #include "device.h"
 #include "mac.h"
@@ -367,21 +368,22 @@ int vnt_set_short_slot_time(struct vnt_private *priv)
 
 	ret = vnt_control_in_u8(priv, MESSAGE_REQUEST_BBREG, 0xe7, &bb_vga);
 	if (ret)
-		goto end;
+		return ret;
 
 	if (bb_vga == priv->bb_vga[0])
 		priv->bb_rx_conf |= 0x20;
 
-	ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x0a,
-				 priv->bb_rx_conf);
-
-end:
-	return ret;
+	return vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x0a,
+				  priv->bb_rx_conf);
 }
 
-void vnt_set_vga_gain_offset(struct vnt_private *priv, u8 data)
+int vnt_set_vga_gain_offset(struct vnt_private *priv, u8 data)
 {
-	vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xE7, data);
+	int ret;
+
+	ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xE7, data);
+	if (ret)
+		return ret;
 
 	/* patch for 3253B0 Baseband with Cardbus module */
 	if (priv->short_slot_time)
@@ -389,7 +391,8 @@ void vnt_set_vga_gain_offset(struct vnt_private *priv, u8 data)
 	else
 		priv->bb_rx_conf |= 0x20; /* 0010 0000 */
 
-	vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x0a, priv->bb_rx_conf);
+	return vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x0a,
+				  priv->bb_rx_conf);
 }
 
 /*
@@ -430,12 +433,13 @@ int vnt_exit_deep_sleep(struct vnt_private *priv)
 	return vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x0d, 0x01);
 }
 
-void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
+int vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
 {
 	const struct vnt_threshold *threshold = NULL;
 	u8 length;
 	u8 cr_201, cr_206;
 	u8 ed_inx;
+	int ret;
 
 	switch (priv->rf_type) {
 	case RF_AL2230:
@@ -458,7 +462,7 @@ void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
 	}
 
 	if (!threshold)
-		return;
+		return -EINVAL;
 
 	for (ed_inx = scanning ? 0 : length - 1; ed_inx > 0; ed_inx--) {
 		if (priv->bb_pre_ed_rssi <= threshold[ed_inx].bb_pre_ed_rssi)
@@ -469,14 +473,17 @@ void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
 	cr_206 = threshold[ed_inx].cr_206;
 
 	if (ed_inx == priv->bb_pre_ed_index && !scanning)
-		return;
+		return 0;
 
 	priv->bb_pre_ed_index = ed_inx;
 
 	dev_dbg(&priv->usb->dev, "%s bb_pre_ed_rssi %d\n",
 		__func__, priv->bb_pre_ed_rssi);
 
-	vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xc9, cr_201);
-	vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xce, cr_206);
+	ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xc9, cr_201);
+	if (ret)
+		return ret;
+
+	return vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xce, cr_206);
 }
 
diff --git a/drivers/staging/vt6656/baseband.h b/drivers/staging/vt6656/baseband.h
index ee7325d942fe..12456ebc23ec 100644
--- a/drivers/staging/vt6656/baseband.h
+++ b/drivers/staging/vt6656/baseband.h
@@ -67,11 +67,11 @@
 #define TOP_RATE_1M         0x00100000
 
 int vnt_set_short_slot_time(struct vnt_private *priv);
-void vnt_set_vga_gain_offset(struct vnt_private *priv, u8 data);
+int vnt_set_vga_gain_offset(struct vnt_private *priv, u8 data);
 int vnt_set_antenna_mode(struct vnt_private *priv, u8 antenna_mode);
 int vnt_vt3184_init(struct vnt_private *priv);
 int vnt_set_deep_sleep(struct vnt_private *priv);
 int vnt_exit_deep_sleep(struct vnt_private *priv);
-void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning);
+int vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning);
 
 #endif /* __BASEBAND_H__ */
diff --git a/drivers/staging/vt6656/card.c b/drivers/staging/vt6656/card.c
index 939bf11d5a6f..341796da2561 100644
--- a/drivers/staging/vt6656/card.c
+++ b/drivers/staging/vt6656/card.c
@@ -27,6 +27,7 @@
  */
 
 #include <linux/bitops.h>
+#include <linux/errno.h>
 #include "device.h"
 #include "card.h"
 #include "baseband.h"
@@ -55,10 +56,12 @@ static const u16 cw_rxbcntsf_off[MAX_RATE] = {
  *  Out:
  *      none
  */
-void vnt_set_channel(struct vnt_private *priv, u32 connection_channel)
+int vnt_set_channel(struct vnt_private *priv, u32 connection_channel)
 {
+	int ret;
+
 	if (connection_channel > CB_MAX_CHANNEL || !connection_channel)
-		return;
+		return -EINVAL;
 
 	/* clear NAV */
 	vnt_mac_reg_bits_on(priv, MAC_REG_MACCR, MACCR_CLRNAV);
@@ -67,11 +70,13 @@ void vnt_set_channel(struct vnt_private *priv, u32 connection_channel)
 	vnt_mac_reg_bits_off(priv, MAC_REG_CHANNEL,
 			     (BIT(7) | BIT(5) | BIT(4)));
 
-	vnt_control_out(priv, MESSAGE_TYPE_SELECT_CHANNEL,
-			connection_channel, 0, 0, NULL);
+	ret = vnt_control_out(priv, MESSAGE_TYPE_SELECT_CHANNEL,
+			      connection_channel, 0, 0, NULL);
+	if (ret)
+		return ret;
 
-	vnt_control_out_u8(priv, MESSAGE_REQUEST_MACREG, MAC_REG_CHANNEL,
-			   (u8)(connection_channel | 0x80));
+	return vnt_control_out_u8(priv, MESSAGE_REQUEST_MACREG, MAC_REG_CHANNEL,
+				  (u8)(connection_channel | 0x80));
 }
 
 static const u8 vnt_rspinf_b_short_table[] = {
@@ -107,10 +112,11 @@ static const u8 vnt_rspinf_gb_table[] = {
  *
  */
 
-void vnt_set_rspinf(struct vnt_private *priv, u8 bb_type)
+int vnt_set_rspinf(struct vnt_private *priv, u8 bb_type)
 {
 	const u8 *data;
 	u16 len;
+	int ret;
 
 	if (priv->preamble_type) {
 		data = vnt_rspinf_b_short_table;
@@ -121,8 +127,10 @@ void vnt_set_rspinf(struct vnt_private *priv, u8 bb_type)
 	}
 
 	 /* RSPINF_b_1 to RSPINF_b_11 */
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_RSPINF_B_1,
-			MESSAGE_REQUEST_MACREG, len, data);
+	ret = vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_RSPINF_B_1,
+			      MESSAGE_REQUEST_MACREG, len, data);
+	if (ret)
+		return ret;
 
 	if (bb_type == BB_TYPE_11A) {
 		data = vnt_rspinf_a_table;
@@ -133,8 +141,8 @@ void vnt_set_rspinf(struct vnt_private *priv, u8 bb_type)
 	}
 
 	/* RSPINF_a_6 to RSPINF_a_72 */
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_RSPINF_A_6,
-			MESSAGE_REQUEST_MACREG, len, data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_RSPINF_A_6,
+			       MESSAGE_REQUEST_MACREG, len, data);
 }
 
 /*
@@ -149,10 +157,11 @@ void vnt_set_rspinf(struct vnt_private *priv, u8 bb_type)
  * Return Value: None.
  *
  */
-void vnt_update_ifs(struct vnt_private *priv)
+int vnt_update_ifs(struct vnt_private *priv)
 {
 	u8 max_min = 0;
 	u8 data[4];
+	int ret;
 
 	if (priv->packet_type == PK_TYPE_11A) {
 		priv->slot = C_SLOT_SHORT;
@@ -212,13 +221,15 @@ void vnt_update_ifs(struct vnt_private *priv)
 	data[2] = (u8)priv->eifs;
 	data[3] = (u8)priv->slot;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_SIFS,
-			MESSAGE_REQUEST_MACREG, 4, &data[0]);
+	ret = vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_SIFS,
+			      MESSAGE_REQUEST_MACREG, 4, &data[0]);
+	if (ret)
+		return ret;
 
 	max_min |= 0xa0;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_CWMAXMIN0,
-			MESSAGE_REQUEST_MACREG, 1, &max_min);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_CWMAXMIN0,
+			       MESSAGE_REQUEST_MACREG, 1, &max_min);
 }
 
 void vnt_update_top_rates(struct vnt_private *priv)
@@ -281,8 +292,8 @@ u64 vnt_get_tsf_offset(u8 rx_rate, u64 tsf1, u64 tsf2)
  * Return Value: none
  *
  */
-void vnt_adjust_tsf(struct vnt_private *priv, u8 rx_rate,
-		    u64 time_stamp, u64 local_tsf)
+int vnt_adjust_tsf(struct vnt_private *priv, u8 rx_rate,
+		   u64 time_stamp, u64 local_tsf)
 {
 	u64 tsf_offset = 0;
 	u8 data[8];
@@ -298,8 +309,8 @@ void vnt_adjust_tsf(struct vnt_private *priv, u8 rx_rate,
 	data[6] = (u8)(tsf_offset >> 48);
 	data[7] = (u8)(tsf_offset >> 56);
 
-	vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
-			MESSAGE_REQUEST_TSF, 0, 8, data);
+	return vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
+			       MESSAGE_REQUEST_TSF, 0, 8, data);
 }
 
 /*
@@ -388,7 +399,7 @@ u64 vnt_get_next_tbtt(u64 tsf, u16 beacon_interval)
  * Return Value: none
  *
  */
-void vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval)
+int vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval)
 {
 	u64 next_tbtt = 0;
 	u8 data[8];
@@ -406,8 +417,8 @@ void vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval)
 	data[6] = (u8)(next_tbtt >> 48);
 	data[7] = (u8)(next_tbtt >> 56);
 
-	vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
-			MESSAGE_REQUEST_TBTT, 0, 8, data);
+	return vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
+			       MESSAGE_REQUEST_TBTT, 0, 8, data);
 }
 
 /*
@@ -425,10 +436,11 @@ void vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval)
  * Return Value: none
  *
  */
-void vnt_update_next_tbtt(struct vnt_private *priv, u64 tsf,
-			  u16 beacon_interval)
+int vnt_update_next_tbtt(struct vnt_private *priv, u64 tsf,
+			 u16 beacon_interval)
 {
 	u8 data[8];
+	int ret;
 
 	tsf = vnt_get_next_tbtt(tsf, beacon_interval);
 
@@ -441,10 +453,13 @@ void vnt_update_next_tbtt(struct vnt_private *priv, u64 tsf,
 	data[6] = (u8)(tsf >> 48);
 	data[7] = (u8)(tsf >> 56);
 
-	vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
-			MESSAGE_REQUEST_TBTT, 0, 8, data);
+	ret = vnt_control_out(priv, MESSAGE_TYPE_SET_TSFTBTT,
+			      MESSAGE_REQUEST_TBTT, 0, 8, data);
+	if (ret)
+		return ret;
 
 	dev_dbg(&priv->usb->dev, "%s TBTT: %8llx\n", __func__, tsf);
+	return 0;
 }
 
 /*
@@ -533,8 +548,10 @@ int vnt_radio_power_on(struct vnt_private *priv)
 	return vnt_mac_reg_bits_off(priv, MAC_REG_GPIOCTL1, GPIO3_INTMD);
 }
 
-void vnt_set_bss_mode(struct vnt_private *priv)
+int vnt_set_bss_mode(struct vnt_private *priv)
 {
+	int ret = 0;
+
 	if (priv->rf_type == RF_AIROHA7230 && priv->bb_type == BB_TYPE_11A)
 		vnt_mac_set_bb_type(priv, BB_TYPE_11G);
 	else
@@ -543,11 +560,16 @@ void vnt_set_bss_mode(struct vnt_private *priv)
 	priv->packet_type = vnt_get_pkt_type(priv);
 
 	if (priv->bb_type == BB_TYPE_11A)
-		vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x88, 0x03);
+		ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
+					 0x88, 0x03);
 	else if (priv->bb_type == BB_TYPE_11B)
-		vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x88, 0x02);
+		ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
+					 0x88, 0x02);
 	else if (priv->bb_type == BB_TYPE_11G)
-		vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0x88, 0x08);
+		ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
+					 0x88, 0x08);
+	if (ret)
+		return ret;
 
 	vnt_update_ifs(priv);
 	vnt_set_rspinf(priv, (u8)priv->bb_type);
@@ -556,8 +578,10 @@ void vnt_set_bss_mode(struct vnt_private *priv)
 		if (priv->rf_type == RF_AIROHA7230) {
 			priv->bb_vga[0] = 0x20;
 
-			vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
-					   0xe7, priv->bb_vga[0]);
+			ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
+						 0xe7, priv->bb_vga[0]);
+			if (ret)
+				return ret;
 		}
 
 		priv->bb_vga[2] = 0x10;
@@ -566,8 +590,10 @@ void vnt_set_bss_mode(struct vnt_private *priv)
 		if (priv->rf_type == RF_AIROHA7230) {
 			priv->bb_vga[0] = 0x1c;
 
-			vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
-					   0xe7, priv->bb_vga[0]);
+			ret = vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG,
+						 0xe7, priv->bb_vga[0]);
+			if (ret)
+				return ret;
 		}
 
 		priv->bb_vga[2] = 0x0;
@@ -575,4 +601,5 @@ void vnt_set_bss_mode(struct vnt_private *priv)
 	}
 
 	vnt_set_vga_gain_offset(priv, priv->bb_vga[0]);
+	return 0;
 }
diff --git a/drivers/staging/vt6656/card.h b/drivers/staging/vt6656/card.h
index eaa15d0c291a..a524fdc60ae3 100644
--- a/drivers/staging/vt6656/card.h
+++ b/drivers/staging/vt6656/card.h
@@ -25,23 +25,23 @@
 
 struct vnt_private;
 
-void vnt_set_channel(struct vnt_private *priv, u32 connection_channel);
-void vnt_set_rspinf(struct vnt_private *priv, u8 bb_type);
-void vnt_update_ifs(struct vnt_private *priv);
+int vnt_set_channel(struct vnt_private *priv, u32 connection_channel);
+int vnt_set_rspinf(struct vnt_private *priv, u8 bb_type);
+int vnt_update_ifs(struct vnt_private *priv);
 void vnt_update_top_rates(struct vnt_private *priv);
 bool vnt_ofdm_min_rate(struct vnt_private *priv);
-void vnt_adjust_tsf(struct vnt_private *priv, u8 rx_rate,
-		    u64 time_stamp, u64 local_tsf);
+int vnt_adjust_tsf(struct vnt_private *priv, u8 rx_rate,
+		   u64 time_stamp, u64 local_tsf);
 bool vnt_get_current_tsf(struct vnt_private *priv, u64 *current_tsf);
 bool vnt_clear_current_tsf(struct vnt_private *priv);
-void vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval);
-void vnt_update_next_tbtt(struct vnt_private *priv, u64 tsf,
-			  u16 beacon_interval);
+int vnt_reset_next_tbtt(struct vnt_private *priv, u16 beacon_interval);
+int vnt_update_next_tbtt(struct vnt_private *priv, u64 tsf,
+			 u16 beacon_interval);
 u64 vnt_get_next_tbtt(u64 tsf, u16 beacon_interval);
 u64 vnt_get_tsf_offset(u8 rx_rate, u64 tsf1, u64 tsf2);
 int vnt_radio_power_off(struct vnt_private *priv);
 int vnt_radio_power_on(struct vnt_private *priv);
 u8 vnt_get_pkt_type(struct vnt_private *priv);
-void vnt_set_bss_mode(struct vnt_private *priv);
+int vnt_set_bss_mode(struct vnt_private *priv);
 
 #endif /* __CARD_H__ */
diff --git a/drivers/staging/vt6656/mac.c b/drivers/staging/vt6656/mac.c
index 5cacf6e60e90..639172fad0f3 100644
--- a/drivers/staging/vt6656/mac.c
+++ b/drivers/staging/vt6656/mac.c
@@ -35,12 +35,13 @@
  * Return Value: none
  *
  */
-void vnt_mac_set_filter(struct vnt_private *priv, u64 mc_filter)
+int vnt_mac_set_filter(struct vnt_private *priv, u64 mc_filter)
 {
 	__le64 le_mc = cpu_to_le64(mc_filter);
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_MAR0,
-			MESSAGE_REQUEST_MACREG, sizeof(le_mc), (u8 *)&le_mc);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_MAR0,
+			       MESSAGE_REQUEST_MACREG, sizeof(le_mc),
+			       (u8 *)&le_mc);
 }
 
 /*
@@ -54,20 +55,21 @@ void vnt_mac_set_filter(struct vnt_private *priv, u64 mc_filter)
  *
  *
  */
-void vnt_mac_shutdown(struct vnt_private *priv)
+int vnt_mac_shutdown(struct vnt_private *priv)
 {
-	vnt_control_out(priv, MESSAGE_TYPE_MACSHUTDOWN, 0, 0, 0, NULL);
+	return vnt_control_out(priv, MESSAGE_TYPE_MACSHUTDOWN, 0, 0, 0, NULL);
 }
 
-void vnt_mac_set_bb_type(struct vnt_private *priv, u8 type)
+int vnt_mac_set_bb_type(struct vnt_private *priv, u8 type)
 {
 	u8 data[2];
 
 	data[0] = type;
 	data[1] = EnCFG_BBType_MASK;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
-			MESSAGE_REQUEST_MACREG,	ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
+			       MESSAGE_REQUEST_MACREG,	ARRAY_SIZE(data),
+			       data);
 }
 
 /*
@@ -84,10 +86,10 @@ void vnt_mac_set_bb_type(struct vnt_private *priv, u8 type)
  * Return Value: none
  *
  */
-void vnt_mac_disable_keyentry(struct vnt_private *priv, u8 entry_idx)
+int vnt_mac_disable_keyentry(struct vnt_private *priv, u8 entry_idx)
 {
-	vnt_control_out(priv, MESSAGE_TYPE_CLRKEYENTRY, 0, 0,
-			sizeof(entry_idx), &entry_idx);
+	return vnt_control_out(priv, MESSAGE_TYPE_CLRKEYENTRY, 0, 0,
+			       sizeof(entry_idx), &entry_idx);
 }
 
 /*
@@ -104,8 +106,8 @@ void vnt_mac_disable_keyentry(struct vnt_private *priv, u8 entry_idx)
  * Return Value: none
  *
  */
-void vnt_mac_set_keyentry(struct vnt_private *priv, u16 key_ctl, u32 entry_idx,
-			  u32 key_idx, u8 *addr, u8 *key)
+int vnt_mac_set_keyentry(struct vnt_private *priv, u16 key_ctl, u32 entry_idx,
+			 u32 key_idx, u8 *addr, u8 *key)
 {
 	struct vnt_mac_set_key set_key;
 	u16 offset;
@@ -124,9 +126,9 @@ void vnt_mac_set_keyentry(struct vnt_private *priv, u16 key_ctl, u32 entry_idx,
 	dev_dbg(&priv->usb->dev, "offset %d key ctl %d set key %24ph\n",
 		offset, key_ctl, (u8 *)&set_key);
 
-	vnt_control_out(priv, MESSAGE_TYPE_SETKEY, offset,
-			(u16)key_idx, sizeof(struct vnt_mac_set_key),
-			(u8 *)&set_key);
+	return vnt_control_out(priv, MESSAGE_TYPE_SETKEY, offset,
+			       (u16)key_idx, sizeof(struct vnt_mac_set_key),
+			       (u8 *)&set_key);
 }
 
 int vnt_mac_reg_bits_off(struct vnt_private *priv, u8 reg_ofs, u8 bits)
@@ -151,76 +153,76 @@ int vnt_mac_reg_bits_on(struct vnt_private *priv, u8 reg_ofs, u8 bits)
 			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_write_word(struct vnt_private *priv, u8 reg_ofs, u16 word)
+int vnt_mac_write_word(struct vnt_private *priv, u8 reg_ofs, u16 word)
 {
 	u8 data[2];
 
 	data[0] = (u8)(word & 0xff);
 	data[1] = (u8)(word >> 8);
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, reg_ofs,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, reg_ofs,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_set_bssid_addr(struct vnt_private *priv, u8 *addr)
+int vnt_mac_set_bssid_addr(struct vnt_private *priv, u8 *addr)
 {
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_BSSID0,
-			MESSAGE_REQUEST_MACREG, ETH_ALEN, addr);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_BSSID0,
+			       MESSAGE_REQUEST_MACREG, ETH_ALEN, addr);
 }
 
-void vnt_mac_enable_protect_mode(struct vnt_private *priv)
+int vnt_mac_enable_protect_mode(struct vnt_private *priv)
 {
 	u8 data[2];
 
 	data[0] = EnCFG_ProtectMd;
 	data[1] = EnCFG_ProtectMd;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_disable_protect_mode(struct vnt_private *priv)
+int vnt_mac_disable_protect_mode(struct vnt_private *priv)
 {
 	u8 data[2];
 
 	data[0] = 0;
 	data[1] = EnCFG_ProtectMd;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG0,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_enable_barker_preamble_mode(struct vnt_private *priv)
+int vnt_mac_enable_barker_preamble_mode(struct vnt_private *priv)
 {
 	u8 data[2];
 
 	data[0] = EnCFG_BarkerPream;
 	data[1] = EnCFG_BarkerPream;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG2,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG2,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_disable_barker_preamble_mode(struct vnt_private *priv)
+int vnt_mac_disable_barker_preamble_mode(struct vnt_private *priv)
 {
 	u8 data[2];
 
 	data[0] = 0;
 	data[1] = EnCFG_BarkerPream;
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG2,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE_MASK, MAC_REG_ENCFG2,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
-void vnt_mac_set_beacon_interval(struct vnt_private *priv, u16 interval)
+int vnt_mac_set_beacon_interval(struct vnt_private *priv, u16 interval)
 {
 	u8 data[2];
 
 	data[0] = (u8)(interval & 0xff);
 	data[1] = (u8)(interval >> 8);
 
-	vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_BI,
-			MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
+	return vnt_control_out(priv, MESSAGE_TYPE_WRITE, MAC_REG_BI,
+			       MESSAGE_REQUEST_MACREG, ARRAY_SIZE(data), data);
 }
 
 int vnt_mac_set_led(struct vnt_private *priv, u8 state, u8 led)
diff --git a/drivers/staging/vt6656/mac.h b/drivers/staging/vt6656/mac.h
index b01d9ee8677e..dae70b5c7634 100644
--- a/drivers/staging/vt6656/mac.h
+++ b/drivers/staging/vt6656/mac.h
@@ -355,21 +355,21 @@ struct vnt_mac_set_key {
 	u8 key[WLAN_KEY_LEN_CCMP];
 } __packed;
 
-void vnt_mac_set_filter(struct vnt_private *priv, u64 mc_filter);
-void vnt_mac_shutdown(struct vnt_private *priv);
-void vnt_mac_set_bb_type(struct vnt_private *priv, u8 type);
-void vnt_mac_disable_keyentry(struct vnt_private *priv, u8 entry_idx);
-void vnt_mac_set_keyentry(struct vnt_private *priv, u16 key_ctl, u32 entry_idx,
-			  u32 key_idx, u8 *addr, u8 *key);
+int vnt_mac_set_filter(struct vnt_private *priv, u64 mc_filter);
+int vnt_mac_shutdown(struct vnt_private *priv);
+int vnt_mac_set_bb_type(struct vnt_private *priv, u8 type);
+int vnt_mac_disable_keyentry(struct vnt_private *priv, u8 entry_idx);
+int vnt_mac_set_keyentry(struct vnt_private *priv, u16 key_ctl, u32 entry_idx,
+			 u32 key_idx, u8 *addr, u8 *key);
 int vnt_mac_reg_bits_off(struct vnt_private *priv, u8 reg_ofs, u8 bits);
 int vnt_mac_reg_bits_on(struct vnt_private *priv, u8 reg_ofs, u8 bits);
-void vnt_mac_write_word(struct vnt_private *priv, u8 reg_ofs, u16 word);
-void vnt_mac_set_bssid_addr(struct vnt_private *priv, u8 *addr);
-void vnt_mac_enable_protect_mode(struct vnt_private *priv);
-void vnt_mac_disable_protect_mode(struct vnt_private *priv);
-void vnt_mac_enable_barker_preamble_mode(struct vnt_private *priv);
-void vnt_mac_disable_barker_preamble_mode(struct vnt_private *priv);
-void vnt_mac_set_beacon_interval(struct vnt_private *priv, u16 interval);
+int vnt_mac_write_word(struct vnt_private *priv, u8 reg_ofs, u16 word);
+int vnt_mac_set_bssid_addr(struct vnt_private *priv, u8 *addr);
+int vnt_mac_enable_protect_mode(struct vnt_private *priv);
+int vnt_mac_disable_protect_mode(struct vnt_private *priv);
+int vnt_mac_enable_barker_preamble_mode(struct vnt_private *priv);
+int vnt_mac_disable_barker_preamble_mode(struct vnt_private *priv);
+int vnt_mac_set_beacon_interval(struct vnt_private *priv, u16 interval);
 int vnt_mac_set_led(struct vnt_private *privpriv, u8 state, u8 led);
 
 #endif /* __MAC_H__ */
diff --git a/drivers/staging/vt6656/power.c b/drivers/staging/vt6656/power.c
index 7a086c72d5a8..2d8d5a332a63 100644
--- a/drivers/staging/vt6656/power.c
+++ b/drivers/staging/vt6656/power.c
@@ -87,17 +87,23 @@ void vnt_enable_power_saving(struct vnt_private *priv, u16 listen_interval)
  *
  */
 
-void vnt_disable_power_saving(struct vnt_private *priv)
+int vnt_disable_power_saving(struct vnt_private *priv)
 {
+	int ret;
+
 	/* disable power saving hw function */
-	vnt_control_out(priv, MESSAGE_TYPE_DISABLE_PS, 0,
-			0, 0, NULL);
+	ret = vnt_control_out(priv, MESSAGE_TYPE_DISABLE_PS, 0,
+			      0, 0, NULL);
+	if (ret)
+		return ret;
 
 	/* clear AutoSleep */
 	vnt_mac_reg_bits_off(priv, MAC_REG_PSCFG, PSCFG_AUTOSLEEP);
 
 	/* set always listen beacon */
 	vnt_mac_reg_bits_on(priv, MAC_REG_PSCTL, PSCTL_ALBCN);
+
+	return 0;
 }
 
 /*
diff --git a/drivers/staging/vt6656/power.h b/drivers/staging/vt6656/power.h
index 58755ae16e5a..160872026db3 100644
--- a/drivers/staging/vt6656/power.h
+++ b/drivers/staging/vt6656/power.h
@@ -18,7 +18,7 @@
 
 #define C_PWBT	1000 /* micro sec. power up before TBTT */
 
-void vnt_disable_power_saving(struct vnt_private *priv);
+int vnt_disable_power_saving(struct vnt_private *priv);
 void vnt_enable_power_saving(struct vnt_private *priv, u16 listen_interval);
 int vnt_next_tbtt_wakeup(struct vnt_private *priv);