Driver Core: usb: add nodename support for usb drivers.

This adds support for USB drivers to report their requested nodename to
userspace.  It also updates a number of USB drivers to provide the
needed subdirectory and device name to be used for them.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/hid/usbhid/hiddev.c

@@ -850,8 +850,14 @@ static const struct file_operations hiddev_fops = {
 #endif
 };
 
+static char *hiddev_nodename(struct device *dev)
+{
+	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
+}
+
 static struct usb_class_driver hiddev_class = {
 	.name =		"hiddev%d",
+	.nodename =	hiddev_nodename,
 	.fops =		&hiddev_fops,
 	.minor_base =	HIDDEV_MINOR_BASE,
 };
@@ -955,7 +961,6 @@ static int hiddev_usbd_probe(struct usb_interface *intf,
 	return -ENODEV;
 }
 
-
 static /* const */ struct usb_driver hiddev_driver = {
 	.name =		"hiddev",
 	.probe =	hiddev_usbd_probe,

drivers/media/video/dabusb.c

@@ -747,8 +747,14 @@ static const struct file_operations dabusb_fops =
 	.release =	dabusb_release,
 };
 
+static char *dabusb_nodename(struct device *dev)
+{
+	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
+}
+
 static struct usb_class_driver dabusb_class = {
 	.name =		"dabusb%d",
+	.nodename =	dabusb_nodename,
 	.fops =		&dabusb_fops,
 	.minor_base =	DABUSB_MINOR,
 };

drivers/usb/class/usblp.c

@@ -1057,8 +1057,14 @@ static const struct file_operations usblp_fops = {
 	.release =	usblp_release,
 };
 
+static char *usblp_nodename(struct device *dev)
+{
+	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
+}
+
 static struct usb_class_driver usblp_class = {
 	.name =		"lp%d",
+	.nodename =	usblp_nodename,
 	.fops =		&usblp_fops,
 	.minor_base =	USBLP_MINOR_BASE,
 };

drivers/usb/core/file.c

@@ -67,6 +67,16 @@ static struct usb_class {
 	struct class *class;
 } *usb_class;
 
+static char *usb_nodename(struct device *dev)
+{
+	struct usb_class_driver *drv;
+
+	drv = dev_get_drvdata(dev);
+	if (!drv || !drv->nodename)
+		return NULL;
+	return drv->nodename(dev);
+}
+
 static int init_usb_class(void)
 {
 	int result = 0;
@@ -90,6 +100,7 @@ static int init_usb_class(void)
 		kfree(usb_class);
 		usb_class = NULL;
 	}
+	usb_class->class->nodename = usb_nodename;
 
 exit:
 	return result;
@@ -198,7 +209,7 @@ int usb_register_dev(struct usb_interface *intf,
 	else
 		temp = name;
 	intf->usb_dev = device_create(usb_class->class, &intf->dev,
-				      MKDEV(USB_MAJOR, minor), NULL,
+				      MKDEV(USB_MAJOR, minor), class_driver,
 				      "%s", temp);
 	if (IS_ERR(intf->usb_dev)) {
 		down_write(&minor_rwsem);

drivers/usb/core/usb.c

@@ -305,10 +305,21 @@ static struct dev_pm_ops usb_device_pm_ops = {
 
 #endif	/* CONFIG_PM */
 
+
+static char *usb_nodename(struct device *dev)
+{
+	struct usb_device *usb_dev;
+
+	usb_dev = to_usb_device(dev);
+	return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
+			 usb_dev->bus->busnum, usb_dev->devnum);
+}
+
 struct device_type usb_device_type = {
 	.name =		"usb_device",
 	.release =	usb_release_dev,
 	.uevent =	usb_dev_uevent,
+	.nodename = 	usb_nodename,
 	.pm =		&usb_device_pm_ops,
 };
 

drivers/usb/misc/iowarrior.c

@@ -726,12 +726,18 @@ static const struct file_operations iowarrior_fops = {
 	.poll = iowarrior_poll,
 };
 
+static char *iowarrior_nodename(struct device *dev)
+{
+	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
+}
+
 /*
  * usb class driver info in order to get a minor number from the usb core,
  * and to have the device registered with devfs and the driver core
  */
 static struct usb_class_driver iowarrior_class = {
 	.name = "iowarrior%d",
+	.nodename = iowarrior_nodename,
 	.fops = &iowarrior_fops,
 	.minor_base = IOWARRIOR_MINOR_BASE,
 };

drivers/usb/misc/legousbtower.c

@@ -266,12 +266,18 @@ static const struct file_operations tower_fops = {
 	.llseek =	tower_llseek,
 };
 
+static char *legousbtower_nodename(struct device *dev)
+{
+	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
+}
+
 /*
  * usb class driver info in order to get a minor number from the usb core,
  * and to have the device registered with the driver core
  */
 static struct usb_class_driver tower_class = {
 	.name =		"legousbtower%d",
+	.nodename = 	legousbtower_nodename,
 	.fops =		&tower_fops,
 	.minor_base =	LEGO_USB_TOWER_MINOR_BASE,
 };

include/linux/usb.h

@@ -869,6 +869,8 @@ struct usb_driver {
  * struct usb_device_driver - identifies USB device driver to usbcore
  * @name: The driver name should be unique among USB drivers,
  *	and should normally be the same as the module name.
+ * @nodename: Callback to provide a naming hint for a possible
+ *	device node to create.
  * @probe: Called to see if the driver is willing to manage a particular
  *	device.  If it is, probe returns zero and uses dev_set_drvdata()
  *	to associate driver-specific data with the device.  If unwilling
@@ -912,6 +914,7 @@ extern struct bus_type usb_bus_type;
  */
 struct usb_class_driver {
 	char *name;
+	char *(*nodename)(struct device *dev);
 	const struct file_operations *fops;
 	int minor_base;
 };