diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index b4bbf8f..e54e468 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2007,7 +2007,6 @@
 	/* host side needs more setup */
 	if (is_host_enabled(musb)) {
 		struct usb_hcd	*hcd = musb_to_hcd(musb);
-		u8 busctl;
 
 		otg_set_host(musb->xceiv, &hcd->self);
 
@@ -2018,9 +2017,9 @@
 
 		/* program PHY to use external vBus if required */
 		if (plat->extvbus) {
-			busctl = musb_readb(musb->mregs, MUSB_ULPI_BUSCONTROL);
+			u8 busctl = musb_read_ulpi_buscontrol(musb->mregs);
 			busctl |= MUSB_ULPI_USE_EXTVBUS;
-			musb_writeb(musb->mregs, MUSB_ULPI_BUSCONTROL, busctl);
+			musb_write_ulpi_buscontrol(musb->mregs, busctl);
 		}
 	}
 
diff --git a/drivers/usb/musb/musb_regs.h b/drivers/usb/musb/musb_regs.h
index 8d8062b..327d0ed 100644
--- a/drivers/usb/musb/musb_regs.h
+++ b/drivers/usb/musb/musb_regs.h
@@ -326,6 +326,11 @@
 	musb_writew(mbase, MUSB_RXFIFOADD, c_off);
 }
 
+static inline void musb_write_ulpi_buscontrol(void __iomem *mbase, u8 val)
+{
+	musb_writeb(mbase, MUSB_ULPI_BUSCONTROL, val);
+}
+
 static inline u8 musb_read_txfifosz(void __iomem *mbase)
 {
 	return musb_readb(mbase, MUSB_TXFIFOSZ);
@@ -346,6 +351,11 @@
 	return musb_readw(mbase, MUSB_RXFIFOADD);
 }
 
+static inline u8 musb_read_ulpi_buscontrol(void __iomem *mbase)
+{
+	return musb_readb(mbase, MUSB_ULPI_BUSCONTROL);
+}
+
 static inline u8 musb_read_configdata(void __iomem *mbase)
 {
 	musb_writeb(mbase, MUSB_INDEX, 0);
@@ -510,6 +520,10 @@
 {
 }
 
+static inline void musb_write_ulpi_buscontrol(void __iomem *mbase, u8 val)
+{
+}
+
 static inline u8 musb_read_txfifosz(void __iomem *mbase)
 {
 }
@@ -526,6 +540,11 @@
 {
 }
 
+static inline u8 musb_read_ulpi_buscontrol(void __iomem *mbase)
+{
+	return 0;
+}
+
 static inline u8 musb_read_configdata(void __iomem *mbase)
 {
 	return 0;