OMAP3: PM: Ensure MUSB block can idle when driver not loaded

Otherwise, bootloaders may leave MUSB in a state which prevents
retention.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-omap2/Makefile

@@ -57,6 +57,4 @@ obj-$(CONFIG_MACH_NOKIA_RX51)		+= board-rx51.o \
 					   mmc-twl4030.o
 
 # Platform specific device init code
-ifeq ($(CONFIG_USB_MUSB_SOC),y)
 obj-y					+= usb-musb.o
-endif

arch/arm/mach-omap2/usb-musb.c

@@ -31,6 +31,17 @@
 #include <mach/mux.h>
 #include <mach/usb.h>
 
+#define OTG_SYSCONFIG	(OMAP34XX_HSUSB_OTG_BASE + 0x404)
+
+static void __init usb_musb_pm_init(void)
+{
+	/* Ensure force-idle mode for OTG controller */
+	if (cpu_is_omap34xx())
+		omap_writel(0, OTG_SYSCONFIG);
+}
+
+#ifdef CONFIG_USB_MUSB_SOC
+
 static struct resource musb_resources[] = {
 	[0] = { /* start and end set dynamically */
 		.flags	= IORESOURCE_MEM,
@@ -183,4 +194,13 @@ void __init usb_musb_init(void)
 		printk(KERN_ERR "Unable to register HS-USB (MUSB) device\n");
 		return;
 	}
+
+	usb_musb_pm_init();
+}
+
+#else
+void __init usb_musb_init(void)
+{
+	usb_musb_pm_init();
 }
+#endif /* CONFIG_USB_MUSB_SOC */

arch/arm/plat-omap/include/mach/usb.h

@@ -27,13 +27,7 @@
 #define UDC_BASE			OMAP2_UDC_BASE
 #define OMAP_OHCI_BASE			OMAP2_OHCI_BASE
 
-#ifdef CONFIG_USB_MUSB_SOC
 extern void usb_musb_init(void);
-#else
-static inline void usb_musb_init(void)
-{
-}
-#endif
 
 #endif