USB: make usbdevices export their device nodes instead of using a separate class

o The "real" usb-devices export now a device node which can
  populate /dev/bus/usb.

o The usb_device class is optional now and can be disabled in the
  kernel config. Major/minor of the "real" devices and class devices
  are the same.

o The environment of the usb-device event contains DEVNUM and BUSNUM to
  help udev and get rid of the ugly udev rule we need for the class
  devices.

o The usb-devices and usb-interfaces share the same bus, so I used
  the new "struct device_type" to let these devices identify
  themselves. This also removes the current logic of using a magic
  platform-pointer.
  The name of the device_type is also added to the environment
  which makes it easier to distinguish the different kinds of devices
  on the same subsystem.

  It looks like this:
    add@/devices/pci0000:00/0000:00:1d.1/usb2/2-1
    ACTION=add
    DEVPATH=/devices/pci0000:00/0000:00:1d.1/usb2/2-1
    SUBSYSTEM=usb
    SEQNUM=1533
    MAJOR=189
    MINOR=131
    DEVTYPE=usb_device
    PRODUCT=46d/c03e/2000
    TYPE=0/0/0
    BUSNUM=002
    DEVNUM=004

This udev rule works as a replacement for usb_device class devices:
  SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \
    NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644"

Updated patch, which needs the device_type patches in Greg's tree.

I also got a bugzilla assigned for this. :)
  https://bugzilla.novell.com/show_bug.cgi?id=250659


Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 63 insertions, 2 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index c359ccb..da4ee07 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1305,7 +1305,7 @@ int usb_reset_configuration(struct usb_device *dev)
 	return 0;
 }
 
-static void release_interface(struct device *dev)
+void usb_release_interface(struct device *dev)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_interface_cache *intfc =
@@ -1315,6 +1315,67 @@ static void release_interface(struct device *dev)
 	kfree(intf);
 }
 
+#ifdef	CONFIG_HOTPLUG
+static int usb_if_uevent(struct device *dev, char **envp, int num_envp,
+		 char *buffer, int buffer_size)
+{
+	struct usb_device *usb_dev;
+	struct usb_interface *intf;
+	struct usb_host_interface *alt;
+	int i = 0;
+	int length = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	/* driver is often null here; dev_dbg() would oops */
+	pr_debug ("usb %s: uevent\n", dev->bus_id);
+
+	intf = to_usb_interface(dev);
+	usb_dev = interface_to_usbdev(intf);
+	alt = intf->cur_altsetting;
+
+	if (add_uevent_var(envp, num_envp, &i,
+		   buffer, buffer_size, &length,
+		   "INTERFACE=%d/%d/%d",
+		   alt->desc.bInterfaceClass,
+		   alt->desc.bInterfaceSubClass,
+		   alt->desc.bInterfaceProtocol))
+		return -ENOMEM;
+
+	if (add_uevent_var(envp, num_envp, &i,
+		   buffer, buffer_size, &length,
+		   "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
+		   le16_to_cpu(usb_dev->descriptor.idVendor),
+		   le16_to_cpu(usb_dev->descriptor.idProduct),
+		   le16_to_cpu(usb_dev->descriptor.bcdDevice),
+		   usb_dev->descriptor.bDeviceClass,
+		   usb_dev->descriptor.bDeviceSubClass,
+		   usb_dev->descriptor.bDeviceProtocol,
+		   alt->desc.bInterfaceClass,
+		   alt->desc.bInterfaceSubClass,
+		   alt->desc.bInterfaceProtocol))
+		return -ENOMEM;
+
+	envp[i] = NULL;
+	return 0;
+}
+
+#else
+
+static int usb_if_uevent(struct device *dev, char **envp,
+			 int num_envp, char *buffer, int buffer_size)
+{
+	return -ENODEV;
+}
+#endif	/* CONFIG_HOTPLUG */
+
+struct device_type usb_if_device_type = {
+	.name =		"usb_interface",
+	.release =	usb_release_interface,
+	.uevent =	usb_if_uevent,
+};
+
 /*
  * usb_set_configuration - Makes a particular device setting be current
  * @dev: the device whose configuration is being updated
@@ -1478,8 +1539,8 @@ free_interfaces:
 		intf->dev.parent = &dev->dev;
 		intf->dev.driver = NULL;
 		intf->dev.bus = &usb_bus_type;
+		intf->dev.type = &usb_if_device_type;
 		intf->dev.dma_mask = dev->dev.dma_mask;
-		intf->dev.release = release_interface;
 		device_initialize (&intf->dev);
 		mark_quiesced(intf);
 		sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d",