uwb: document UWB and WUSB sysfs files
Add some brief documentation on the UWB and WUSB related sysfs files.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
diff --git a/Documentation/ABI/testing/sysfs-class-usb_host b/Documentation/ABI/testing/sysfs-class-usb_host
new file mode 100644
index 0000000..46b66ad1
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-usb_host
@@ -0,0 +1,25 @@
+What: /sys/class/usb_host/usb_hostN/wusb_chid
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ Write the CHID (16 space-separated hex octets) for this host controller.
+ This starts the host controller, allowing it to accept connection from
+ WUSB devices.
+
+ Set an all zero CHID to stop the host controller.
+
+What: /sys/class/usb_host/usb_hostN/wusb_trust_timeout
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ Devices that haven't sent a WUSB packet to the host
+ within 'wusb_trust_timeout' ms are considered to have
+ disconnected and are removed. The default value of
+ 4000 ms is the value required by the WUSB
+ specification.
+
+ Since this relates to security (specifically, the
+ lifetime of PTKs and GTKs) it should not be changed
+ from the default.