musb suspend crash prevent hack

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index be123a1..191c9ca 100644 (file)
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2338,6 +2338,7 @@ static int musb_suspend(struct device *dev)
 {
        struct musb     *musb = dev_to_musb(dev);
        unsigned long   flags;
+       int             ret = 0;
 
        spin_lock_irqsave(&musb->lock, flags);
 
@@ -2345,6 +2346,20 @@ static int musb_suspend(struct device *dev)
                /* FIXME force disconnect unless we know USB will wake
                 * the system up quickly enough to respond ...
                 */
+               /*
+                * FIXME: musb must be already runtime suspended at this point.
+                * If it's not, framework will try to suspend it late when
+                * i2c will be off, and twl4030 will want to access it for it's
+                * stuff, causing data abort.
+                */
+               int pm_usage_count =
+                       atomic_read(&musb->controller->power.usage_count);
+               if (pm_usage_count > 1) {
+                       dev_err(dev, "can't suspend while still active, "
+                               "try removing gadget drivers (usage_count %d)\n",
+                               pm_usage_count);
+                       ret = -EBUSY;
+               }
        } else if (is_host_active(musb)) {
                /* we know all the children are suspended; sometimes
                 * they will even be wakeup-enabled.
@@ -2352,7 +2367,7 @@ static int musb_suspend(struct device *dev)
        }
 
        spin_unlock_irqrestore(&musb->lock, flags);
-       return 0;
+       return ret;
 }
 
 static int musb_resume_noirq(struct device *dev)