musb: proper hookup to transceiver drivers

Let the otg_transceiver in MUSB be managed by an external driver;
don't assume it's integrated.  OMAP3 chips need it to be external,
and there may be ways to interact with the transceiver which add
functionality to the system.

Platform init code is responsible for setting up the transeciver,
probably using the NOP transceiver for integrated transceivers.
External ones will use whatever the board init code provided,
such as twl4030 or something more hands-off.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/musb/davinci.c b/drivers/usb/musb/davinci.c
index 6e14e06..180d7da 100644
--- a/drivers/usb/musb/davinci.c
+++ b/drivers/usb/musb/davinci.c
@@ -215,7 +215,7 @@
 	DBG(7, "poll devctl %02x (%s)\n", devctl, otg_state_string(musb));
 
 	spin_lock_irqsave(&musb->lock, flags);
-	switch (musb->xceiv.state) {
+	switch (musb->xceiv->state) {
 	case OTG_STATE_A_WAIT_VFALL:
 		/* Wait till VBUS falls below SessionEnd (~0.2V); the 1.3 RTL
 		 * seems to mis-handle session "start" otherwise (or in our
@@ -226,7 +226,7 @@
 			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
 			break;
 		}
-		musb->xceiv.state = OTG_STATE_A_WAIT_VRISE;
+		musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
 		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
 			MUSB_INTR_VBUSERROR << DAVINCI_USB_USBINT_SHIFT);
 		break;
@@ -251,7 +251,7 @@
 		if (devctl & MUSB_DEVCTL_BDEVICE)
 			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
 		else
-			musb->xceiv.state = OTG_STATE_A_IDLE;
+			musb->xceiv->state = OTG_STATE_A_IDLE;
 		break;
 	default:
 		break;
@@ -325,21 +325,21 @@
 			 * to stop registering in devctl.
 			 */
 			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
-			musb->xceiv.state = OTG_STATE_A_WAIT_VFALL;
+			musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
 			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
 			WARNING("VBUS error workaround (delay coming)\n");
 		} else if (is_host_enabled(musb) && drvvbus) {
 			musb->is_active = 1;
 			MUSB_HST_MODE(musb);
-			musb->xceiv.default_a = 1;
-			musb->xceiv.state = OTG_STATE_A_WAIT_VRISE;
+			musb->xceiv->default_a = 1;
+			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
 			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
 			del_timer(&otg_workaround);
 		} else {
 			musb->is_active = 0;
 			MUSB_DEV_MODE(musb);
-			musb->xceiv.default_a = 0;
-			musb->xceiv.state = OTG_STATE_B_IDLE;
+			musb->xceiv->default_a = 0;
+			musb->xceiv->state = OTG_STATE_B_IDLE;
 			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
 		}
 
@@ -361,7 +361,7 @@
 
 	/* poll for ID change */
 	if (is_otg_enabled(musb)
-			&& musb->xceiv.state == OTG_STATE_B_IDLE)
+			&& musb->xceiv->state == OTG_STATE_B_IDLE)
 		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
 
 	spin_unlock_irqrestore(&musb->lock, flags);
@@ -380,6 +380,11 @@
 	void __iomem	*tibase = musb->ctrl_base;
 	u32		revision;
 
+	usb_nop_xceiv_register();
+	musb->xceiv = otg_get_transceiver();
+	if (!musb->xceiv)
+		return -ENODEV;
+
 	musb->mregs += DAVINCI_BASE_OFFSET;
 
 	clk_enable(musb->clock);
@@ -387,7 +392,7 @@
 	/* returns zero if e.g. not clocked */
 	revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG);
 	if (revision == 0)
-		return -ENODEV;
+		goto fail;
 
 	if (is_host_enabled(musb))
 		setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
@@ -421,6 +426,10 @@
 
 	musb->isr = davinci_interrupt;
 	return 0;
+
+fail:
+	usb_nop_xceiv_unregister();
+	return -ENODEV;
 }
 
 int musb_platform_exit(struct musb *musb)
@@ -431,7 +440,7 @@
 	davinci_source_power(musb, 0 /*off*/, 1);
 
 	/* delay, to avoid problems with module reload */
-	if (is_host_enabled(musb) && musb->xceiv.default_a) {
+	if (is_host_enabled(musb) && musb->xceiv->default_a) {
 		int	maxdelay = 30;
 		u8	devctl, warn = 0;
 
@@ -460,5 +469,7 @@
 
 	clk_disable(musb->clock);
 
+	usb_nop_xceiv_unregister();
+
 	return 0;
 }