USB: MUSB: fix kernel WARNING/oops when unloading module in OTG mode

Since commit 461972d (musb_core: don't call
musb_platform_exit() twice), unloading the driver module results in a WARNING
"kobject: '(null)' (c73de788): is not initialized, yet kobject_put() is being
called." (or even kernel oops) on e.g. DaVincis, though only in the OTG mode.
There exists dubious and unbalanced put_device() call in musb_free() which
takes place only in the OTG mode.  As this commit caused musb_platform_exit()
to be called (and so unregister the NOP transceiver) before this put_device()
call, this function references already freed memory.

On the other hand, all the glue layers miss the otg_put_transceiver() call,
complementary to the otg_get_transceiver() call that they do.  So, I think
the solution is to get rid of the strange put_device() call, and instead
call otg_put_transceiver() in the glue layers...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/blackfin.c

@@ -397,5 +397,6 @@ int musb_platform_exit(struct musb *musb)
 
 	gpio_free(musb->config->gpio_vrsel);
 
+	otg_put_transceiver(musb->xceiv);
 	return 0;
 }

drivers/usb/musb/davinci.c

@@ -446,6 +446,7 @@ int __init musb_platform_init(struct musb *musb, void *board_data)
 fail:
 	clk_disable(musb->clock);
 
+	otg_put_transceiver(musb->xceiv);
 	usb_nop_xceiv_unregister();
 	return -ENODEV;
 }
@@ -496,6 +497,7 @@ int musb_platform_exit(struct musb *musb)
 
 	clk_disable(musb->clock);
 
+	otg_put_transceiver(musb->xceiv);
 	usb_nop_xceiv_unregister();
 
 	return 0;

drivers/usb/musb/musb_core.c

@@ -1926,10 +1926,6 @@ static void musb_free(struct musb *musb)
 		dma_controller_destroy(c);
 	}
 
-#ifdef CONFIG_USB_MUSB_OTG
-	put_device(musb->xceiv->dev);
-#endif
-
 #ifdef CONFIG_USB_MUSB_HDRC_HCD
 	usb_put_hcd(musb_to_hcd(musb));
 #else

drivers/usb/musb/omap2430.c

@@ -320,5 +320,6 @@ int musb_platform_exit(struct musb *musb)
 
 	musb_platform_suspend(musb);
 
+	otg_put_transceiver(musb->xceiv);
 	return 0;
 }

drivers/usb/musb/tusb6010.c

@@ -1152,6 +1152,8 @@ int __init musb_platform_init(struct musb *musb, void *board_data)
 	if (ret < 0) {
 		if (sync)
 			iounmap(sync);
+
+		otg_put_transceiver(musb->xceiv);
 		usb_nop_xceiv_unregister();
 	}
 	return ret;
@@ -1166,6 +1168,8 @@ int musb_platform_exit(struct musb *musb)
 		musb->board_set_power(0);
 
 	iounmap(musb->sync_va);
+
+	otg_put_transceiver(musb->xceiv);
 	usb_nop_xceiv_unregister();
 	return 0;
 }