From 21a9631586a07198e22d278fb8695bdd74d9b5c5 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sat, 3 Aug 2013 16:37:49 +0200 Subject: 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 Signed-off-by: Greg Kroah-Hartman --- Documentation/usb/proc_usb_info.txt | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'Documentation/usb') 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 -- cgit v1.2.3-59-g8ed1b