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authorHans de Goede <hdegoede@redhat.com>2013-08-03 16:37:49 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-08-12 12:24:27 -0700
commit21a9631586a07198e22d278fb8695bdd74d9b5c5 (patch)
tree0f78064a58bb5e9b2a40581ca40e2826d2bbdaf1 /Documentation/usb/proc_usb_info.txt
parentb4f17a488ae2e09bfcf95c0e0b4219c246f1116a (diff)
downloadblackbird-op-linux-21a9631586a07198e22d278fb8695bdd74d9b5c5.tar.gz
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proc_usb_info.txt: Correct documentation about endianness of config descriptors
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>
Diffstat (limited to 'Documentation/usb/proc_usb_info.txt')
-rw-r--r--Documentation/usb/proc_usb_info.txt9
1 files changed, 6 insertions, 3 deletions
diff --git a/Documentation/usb/proc_usb_info.txt b/Documentation/usb/proc_usb_info.txt
index c9c3f0f5ad7b..98be91982677 100644
--- a/Documentation/usb/proc_usb_info.txt
+++ b/Documentation/usb/proc_usb_info.txt
@@ -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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