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>

8 files changed, 56 insertions, 2 deletions

diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index e9b436d2d944..9e9421525fb9 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/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,
diff --git a/drivers/media/video/dabusb.c b/drivers/media/video/dabusb.c
index ba3709bec3f0..ec2f45dde164 100644
--- a/drivers/media/video/dabusb.c
+++ b/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,
 };
diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index d2747a49b974..26c09f0257db 100644
--- a/drivers/usb/class/usblp.c
+++ b/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,
 };
diff --git a/drivers/usb/core/file.c b/drivers/usb/core/file.c
index 997e659ff693..5cef88929b3e 100644
--- a/drivers/usb/core/file.c
+++ b/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);
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 7eee400d3e32..927a27dd2f85 100644
--- a/drivers/usb/core/usb.c
+++ b/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,
 };
 
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index a4ef77ef917d..3c5fe5cee05a 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/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,
 };
diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
index ab0f3226158b..c1e2433f640d 100644
--- a/drivers/usb/misc/legousbtower.c
+++ b/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,
 };
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 3aa2cd1f8d08..34cdfcac4555 100644
--- a/include/linux/usb.h
+++ b/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;
 };