X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fusb%2Fcore%2Fnotify.c;fp=drivers%2Fusb%2Fcore%2Fnotify.c;h=fbbebab52fbd1fbfa23b3d7d48618905067d9424;hb=64ba3f394c830ec48a1c31b53dcae312c56f1604;hp=6b36897ca151998ab28f07c12f0e9baef9e372fe;hpb=be1e6109ac94a859551f8e1774eb9a8469fe055c;p=linux-2.6.git

diff --git a/drivers/usb/core/notify.c b/drivers/usb/core/notify.c
index 6b36897ca..fbbebab52 100644
--- a/drivers/usb/core/notify.c
+++ b/drivers/usb/core/notify.c
@@ -9,13 +9,63 @@
  */
 
 
+#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/notifier.h>
 #include <linux/usb.h>
-#include <linux/mutex.h>
 #include "usb.h"
 
-static BLOCKING_NOTIFIER_HEAD(usb_notifier_list);
+
+static struct notifier_block *usb_notifier_list;
+static DECLARE_MUTEX(usb_notifier_lock);
+
+static void usb_notifier_chain_register(struct notifier_block **list,
+					struct notifier_block *n)
+{
+	down(&usb_notifier_lock);
+	while (*list) {
+		if (n->priority > (*list)->priority)
+			break;
+		list = &((*list)->next);
+	}
+	n->next = *list;
+	*list = n;
+	up(&usb_notifier_lock);
+}
+
+static void usb_notifier_chain_unregister(struct notifier_block **nl,
+				   struct notifier_block *n)
+{
+	down(&usb_notifier_lock);
+	while ((*nl)!=NULL) {
+		if ((*nl)==n) {
+			*nl = n->next;
+			goto exit;
+		}
+		nl=&((*nl)->next);
+	}
+exit:
+	up(&usb_notifier_lock);
+}
+
+static int usb_notifier_call_chain(struct notifier_block **n,
+				   unsigned long val, void *v)
+{
+	int ret=NOTIFY_DONE;
+	struct notifier_block *nb = *n;
+
+	down(&usb_notifier_lock);
+	while (nb) {
+		ret = nb->notifier_call(nb,val,v);
+		if (ret&NOTIFY_STOP_MASK) {
+			goto exit;
+		}
+		nb = nb->next;
+	}
+exit:
+	up(&usb_notifier_lock);
+	return ret;
+}
 
 /**
  * usb_register_notify - register a notifier callback whenever a usb change happens
@@ -25,7 +75,7 @@ static BLOCKING_NOTIFIER_HEAD(usb_notifier_list);
  */
 void usb_register_notify(struct notifier_block *nb)
 {
-	blocking_notifier_chain_register(&usb_notifier_list, nb);
+	usb_notifier_chain_register(&usb_notifier_list, nb);
 }
 EXPORT_SYMBOL_GPL(usb_register_notify);
 
@@ -38,31 +88,27 @@ EXPORT_SYMBOL_GPL(usb_register_notify);
  */
 void usb_unregister_notify(struct notifier_block *nb)
 {
-	blocking_notifier_chain_unregister(&usb_notifier_list, nb);
+	usb_notifier_chain_unregister(&usb_notifier_list, nb);
 }
 EXPORT_SYMBOL_GPL(usb_unregister_notify);
 
 
 void usb_notify_add_device(struct usb_device *udev)
 {
-	blocking_notifier_call_chain(&usb_notifier_list, USB_DEVICE_ADD, udev);
+	usb_notifier_call_chain(&usb_notifier_list, USB_DEVICE_ADD, udev);
 }
 
 void usb_notify_remove_device(struct usb_device *udev)
 {
-	/* Protect against simultaneous usbfs open */
-	mutex_lock(&usbfs_mutex);
-	blocking_notifier_call_chain(&usb_notifier_list,
-			USB_DEVICE_REMOVE, udev);
-	mutex_unlock(&usbfs_mutex);
+	usb_notifier_call_chain(&usb_notifier_list, USB_DEVICE_REMOVE, udev);
 }
 
 void usb_notify_add_bus(struct usb_bus *ubus)
 {
-	blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_ADD, ubus);
+	usb_notifier_call_chain(&usb_notifier_list, USB_BUS_ADD, ubus);
 }
 
 void usb_notify_remove_bus(struct usb_bus *ubus)
 {
-	blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_REMOVE, ubus);
+	usb_notifier_call_chain(&usb_notifier_list, USB_BUS_REMOVE, ubus);
 }