X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fbase%2Fbus.c;h=29f6af554e715ed408f0f23e8da838284dbc9dc7;hb=900b2b463dc6e65ec474d6880412c63c25b3aea9;hp=ab53832d57e5eff507b8e4552983446641f02d51;hpb=efda9452046bdd707b23a85b7846ec33548f84f1;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index ab53832d57e..29f6af554e7 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -133,7 +133,7 @@ static struct kobj_type ktype_bus = {
 decl_subsys(bus, &ktype_bus, NULL);
 
 
-/* Manually detach a device from it's associated driver. */
+/* Manually detach a device from its associated driver. */
 static int driver_helper(struct device *dev, void *data)
 {
 	const char *name = data;
@@ -151,11 +151,16 @@ static ssize_t driver_unbind(struct device_driver *drv,
 	int err = -ENODEV;
 
 	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
-	if ((dev) &&
-	    (dev->driver == drv)) {
+	if (dev && dev->driver == drv) {
+		if (dev->parent)	/* Needed for USB */
+			down(&dev->parent->sem);
 		device_release_driver(dev);
+		if (dev->parent)
+			up(&dev->parent->sem);
 		err = count;
 	}
+	put_device(dev);
+	put_bus(bus);
 	return err;
 }
 static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind);
@@ -173,16 +178,18 @@ static ssize_t driver_bind(struct device_driver *drv,
 	int err = -ENODEV;
 
 	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
-	if ((dev) &&
-	    (dev->driver == NULL)) {
+	if (dev && dev->driver == NULL) {
+		if (dev->parent)	/* Needed for USB */
+			down(&dev->parent->sem);
 		down(&dev->sem);
 		err = driver_probe_device(drv, dev);
 		up(&dev->sem);
-		put_device(dev);
+		if (dev->parent)
+			up(&dev->parent->sem);
 	}
-	if (err)
-		return err;
-	return count;
+	put_device(dev);
+	put_bus(bus);
+	return err;
 }
 static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind);
 
@@ -358,7 +365,7 @@ int bus_add_device(struct device * dev)
 	if (bus) {
 		pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id);
 		device_attach(dev);
-		klist_add_tail(&bus->klist_devices, &dev->knode_bus);
+		klist_add_tail(&dev->knode_bus, &bus->klist_devices);
 		error = device_add_attrs(bus, dev);
 		if (!error) {
 			sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id);
@@ -421,6 +428,26 @@ static void driver_remove_attrs(struct bus_type * bus, struct device_driver * dr
 	}
 }
 
+#ifdef CONFIG_HOTPLUG
+/*
+ * Thanks to drivers making their tables __devinit, we can't allow manual
+ * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled.
+ */
+static void add_bind_files(struct device_driver *drv)
+{
+	driver_create_file(drv, &driver_attr_unbind);
+	driver_create_file(drv, &driver_attr_bind);
+}
+
+static void remove_bind_files(struct device_driver *drv)
+{
+	driver_remove_file(drv, &driver_attr_bind);
+	driver_remove_file(drv, &driver_attr_unbind);
+}
+#else
+static inline void add_bind_files(struct device_driver *drv) {}
+static inline void remove_bind_files(struct device_driver *drv) {}
+#endif
 
 /**
  *	bus_add_driver - Add a driver to the bus.
@@ -446,12 +473,11 @@ int bus_add_driver(struct device_driver * drv)
 		}
 
 		driver_attach(drv);
-		klist_add_tail(&bus->klist_drivers, &drv->knode_bus);
+		klist_add_tail(&drv->knode_bus, &bus->klist_drivers);
 		module_add_driver(drv->owner, drv);
 
 		driver_add_attrs(bus, drv);
-		driver_create_file(drv, &driver_attr_unbind);
-		driver_create_file(drv, &driver_attr_bind);
+		add_bind_files(drv);
 	}
 	return error;
 }
@@ -469,8 +495,7 @@ int bus_add_driver(struct device_driver * drv)
 void bus_remove_driver(struct device_driver * drv)
 {
 	if (drv->bus) {
-		driver_remove_file(drv, &driver_attr_bind);
-		driver_remove_file(drv, &driver_attr_unbind);
+		remove_bind_files(drv);
 		driver_remove_attrs(drv->bus, drv);
 		klist_remove(&drv->knode_bus);
 		pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
@@ -485,8 +510,13 @@ void bus_remove_driver(struct device_driver * drv)
 /* Helper for bus_rescan_devices's iter */
 static int bus_rescan_devices_helper(struct device *dev, void *data)
 {
-	if (!dev->driver)
+	if (!dev->driver) {
+		if (dev->parent)	/* Needed for USB */
+			down(&dev->parent->sem);
 		device_attach(dev);
+		if (dev->parent)
+			up(&dev->parent->sem);
+	}
 	return 0;
 }
 
@@ -566,6 +596,36 @@ static void bus_remove_attrs(struct bus_type * bus)
 	}
 }
 
+static void klist_devices_get(struct klist_node *n)
+{
+	struct device *dev = container_of(n, struct device, knode_bus);
+
+	get_device(dev);
+}
+
+static void klist_devices_put(struct klist_node *n)
+{
+	struct device *dev = container_of(n, struct device, knode_bus);
+
+	put_device(dev);
+}
+
+static void klist_drivers_get(struct klist_node *n)
+{
+	struct device_driver *drv = container_of(n, struct device_driver,
+						 knode_bus);
+
+	get_driver(drv);
+}
+
+static void klist_drivers_put(struct klist_node *n)
+{
+	struct device_driver *drv = container_of(n, struct device_driver,
+						 knode_bus);
+
+	put_driver(drv);
+}
+
 /**
  *	bus_register - register a bus with the system.
  *	@bus:	bus.
@@ -600,8 +660,8 @@ int bus_register(struct bus_type * bus)
 	if (retval)
 		goto bus_drivers_fail;
 
-	klist_init(&bus->klist_devices);
-	klist_init(&bus->klist_drivers);
+	klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put);
+	klist_init(&bus->klist_drivers, klist_drivers_get, klist_drivers_put);
 	bus_add_attrs(bus);
 
 	pr_debug("bus type '%s' registered\n", bus->name);