usb: udc: store usb_udc pointer in struct usb_gadget

Instead of iterate to find usb_udc according to usb_gadget, this
way is easier.

Alan Stern suggests this way too:
http://marc.info/?l=linux-usb&m=142168496528894&w=2

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 9 insertions, 25 deletions

diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c
index 5a81cb086b99..bf7ed777a87d 100644
--- a/drivers/usb/gadget/udc/udc-core.c
+++ b/drivers/usb/gadget/udc/udc-core.c
@@ -128,21 +128,11 @@ EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
 
 static void usb_gadget_state_work(struct work_struct *work)
 {
-        struct usb_gadget       *gadget = work_to_gadget(work);
-        struct usb_udc          *udc = NULL;
-
-        mutex_lock(&udc_lock);
-        list_for_each_entry(udc, &udc_list, list)
-                if (udc->gadget == gadget)
-                        goto found;
-        mutex_unlock(&udc_lock);
+        struct usb_gadget *gadget = work_to_gadget(work);
+        struct usb_udc *udc = gadget->udc;
 
-        return;
-
-found:
-        mutex_unlock(&udc_lock);
-
-        sysfs_notify(&udc->dev.kobj, NULL, "state");
+        if (udc)
+                sysfs_notify(&udc->dev.kobj, NULL, "state");
 }
 
 void usb_gadget_set_state(struct usb_gadget *gadget,
@@ -278,6 +268,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
                 goto err3;
 
         udc->gadget = gadget;
+        gadget->udc = udc;
 
         mutex_lock(&udc_lock);
         list_add_tail(&udc->list, &udc_list);
@@ -348,21 +339,14 @@ static void usb_gadget_remove_driver(struct usb_udc *udc)
  */
 void usb_del_gadget_udc(struct usb_gadget *gadget)
 {
-        struct usb_udc          *udc = NULL;
+        struct usb_udc *udc = gadget->udc;
 
-        mutex_lock(&udc_lock);
-        list_for_each_entry(udc, &udc_list, list)
-                if (udc->gadget == gadget)
-                        goto found;
-
-        dev_err(gadget->dev.parent, "gadget not registered.\n");
-        mutex_unlock(&udc_lock);
-
-        return;
+        if (!udc)
+                return;
 
-found:
         dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
 
+        mutex_lock(&udc_lock);
         list_del(&udc->list);
         mutex_unlock(&udc_lock);