usb: add decriptor of persist fail for some morph usb devices

Some morph devices will morph after being reset and cause persist
to fail. This patch is to add descriptor about this in the
Document/usb/persist.txt

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/usb/persist.txt b/Documentation/usb/persist.txt
index 074b159b77c20344aaa0a4abf7becc8603a2a065..35d70eda9ad627bf0eff7c1193f91fb451126e5b 100644 (file)
--- a/Documentation/usb/persist.txt
+++ b/Documentation/usb/persist.txt
@@ -155,6 +155,9 @@ If the kernel gets fooled in this way, it's almost certain to cause
 data corruption and to crash your system.  You'll have no one to blame
 but yourself.
 
+For those devices with avoid_reset_quirk attribute being set, persist
+maybe fail because they may morph after reset.
+
 YOU HAVE BEEN WARNED!  USE AT YOUR OWN RISK!
 
 That having been said, most of the time there shouldn't be any trouble