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proc_usb_info.txt: Correct documentation about endianness of config d…
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…escriptors

The config descriptors as read from /proc/bus/usb/BBB/DDD are in *bus* endian
format. Correct proc_usb_info.txt to correctly reflect that.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Hans de Goede authored and Greg Kroah-Hartman committed Aug 12, 2013
1 parent b4f17a4 commit 21a9631
Showing 1 changed file with 6 additions and 3 deletions.
9 changes: 6 additions & 3 deletions Documentation/usb/proc_usb_info.txt
Original file line number Diff line number Diff line change
Expand Up @@ -54,9 +54,12 @@ it and 002/048 sometime later.

These files can be read as binary data. The binary data consists
of first the device descriptor, then the descriptors for each
configuration of the device. Multi-byte fields in the device and
configuration descriptors, but not other descriptors, are converted
to host endianness by the kernel. This information is also shown
configuration of the device. Multi-byte fields in the device descriptor
are converted to host endianness by the kernel. The configuration
descriptors are in bus endian format! The configuration descriptor
are wTotalLength bytes apart. If a device returns less configuration
descriptor data than indicated by wTotalLength there will be a hole in
the file for the missing bytes. This information is also shown
in text form by the /proc/bus/usb/devices file, described later.

These files may also be used to write user-level drivers for the USB
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