Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6:
  USB: export autosuspend delay in sysfs
  sysfs: allow attributes to be added to groups
  USB: make autosuspend delay a module parameter
  USB: minor cleanups for sysfs.c
  USB: add a blacklist for devices that can't handle some things we throw at them.
  USB: refactor usb device matching and create usb_device_match
  USB: Wacom driver updates
  gadgetfs: Fixed bug in ep_aio_read_retry.
  USB: Use USB defines in usbmouse.c and usbkbd.c
  USB: add rationale on why usb descriptor structures have to be packed
  USB: ftdi_sio: Adding VID and PID for Tellstick
  UHCI: Eliminate asynchronous skeleton Queue Headers
  UHCI: Add macros for computing DMA values
  USB: Davicom DM9601 usbnet driver
  USB: asix.c - Add JVC-PRX1 ids
  usbmon: Remove erroneous __exit
  USB: add driver for iowarrior devices.
  USB: option: add a bunch of new device ids
  USB: option: remove duplicate device id table

1 files changed, 18 insertions, 4 deletions

diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 245c7253122..1122a6c2c1a 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -1,8 +1,9 @@
 /*
- * This file holds USB constants and structures that are needed for USB
- * device APIs.  These are used by the USB device model, which is defined
- * in chapter 9 of the USB 2.0 specification.  Linux has several APIs in C
- * that need these:
+ * This file holds USB constants and structures that are needed for
+ * USB device APIs.  These are used by the USB device model, which is
+ * defined in chapter 9 of the USB 2.0 specification and in the
+ * Wireless USB 1.0 (spread around).  Linux has several APIs in C that
+ * need these:
  *
  * - the master/host side Linux-USB kernel driver API;
  * - the "usbfs" user space API; and
@@ -14,6 +15,19 @@
  *
  * There's also "Wireless USB", using low power short range radios for
  * peripheral interconnection but otherwise building on the USB framework.
+ *
+ * Note all descriptors are declared '__attribute__((packed))' so that:
+ *
+ * [a] they never get padded, either internally (USB spec writers
+ *     probably handled that) or externally;
+ *
+ * [b] so that accessing bigger-than-a-bytes fields will never
+ *     generate bus errors on any platform, even when the location of
+ *     its descriptor inside a bundle isn't "naturally aligned", and
+ *
+ * [c] for consistency, removing all doubt even when it appears to
+ *     someone that the two other points are non-issues for that
+ *     particular descriptor type.
  */
 
 #ifndef __LINUX_USB_CH9_H