Windows 10 Version 1607 -1909 ONLY: Use file Version Win10.1607 only. DO NOT use file Version Win10.1607 for previous build versions of Windows. Latest Displaylink driver must also be downloaded and installed with the GUWAVKIT4B UWB connection software. Please visit Displaylink.com for the latest Displaylink driver. Not compatible with build 2004. Generated on 2019-Mar-29 from project linux revision v5.1-rc2 Powered by Code Browser 2.1 Generator usage only permitted with license. Code Browser 2.1 Generator usage only. /. Ultra Wide Band. Driver initialization. FIXME: explain. UWB radio controller:. 1. Alloc a uwbrc, zero it. 2. Call uwbrcinit on it to set it up + ops (won't do any. kind of allocation). 3. Register (now it is owned by the UWB stack-deregister before. freeing/destroying).

Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>

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Please visit http://bughost.org/thewiki/Design-overview.txt-1.8 forupdated content.

This code implements a Ultra Wide Band stack for Linux, as well asdrivers for the USB based UWB radio controllers defined in theWireless USB 1.0 specification (including Wireless USB host controllerand an Intel WiNET controller).

Introduction¶

UWB is a wide-band communication protocol that is to serve also as thelow-level protocol for others (much like TCP sits on IP). Currentlythese others are Wireless USB and TCP/IP, but seems Bluetooth andFirewire/1394 are coming along.

UWB uses a band from roughly 3 to 10 GHz, transmitting at a max of~-41dB (or 0.074 uW/MHz--geography specific data is still beingnegotiated w/ regulators, so watch for changes). That band is divided ina bunch of ~1.5 GHz wide channels (or band groups) composed of threesubbands/subchannels (528 MHz each). Each channel is independent of eachother, so you could consider them different 'busses'. Initially thisdriver considers them all a single one.

Radio time is divided in 65536 us long /superframes/, each one dividedin 256 256us long /MASs/ (Media Allocation Slots), which are the basictime/media allocation units for transferring data. At the beginning ofeach superframe there is a Beacon Period (BP), where every devicetransmit its beacon on a single MAS. The length of the BP depends on howmany devices are present and the length of their beacons.

Devices have a MAC (fixed, 48 bit address) and a device (changeable, 16bit address) and send periodic beacons to advertise themselves and passinfo on what they are and do. They advertise their capabilities and abunch of other stuff.

The different logical parts of this driver are:

UWB: the Ultra-Wide-Band stack -- manages the radio andassociated spectrum to allow for devices sharing it. Allows tocontrol bandwidth assignment, beaconing, scanning, etc
WUSB: the layer that sits on top of UWB to provide Wireless USB.The Wireless USB spec defines means to control a UWB radio and todo the actual WUSB.

HWA: Host Wire adapters, your Wireless USB dongle¶

WUSB also defines a device called a Host Wire Adaptor (HWA), which inmere terms is a USB dongle that enables your PC to have UWB and WirelessUSB. The Wireless USB Host Controller in a HWA looks to the host like a[Wireless] USB controller connected via USB (!)

The HWA itself is broken in two or three main interfaces:

RC: Radio control -- this implements an interface to theUltra-Wide-Band radio controller. The driver for this implements aUSB-based UWB Radio Controller to the UWB stack.
HC: the wireless USB host controller. It looks like a USB hostwhose root port is the radio and the WUSB devices connect to it.To the system it looks like a separate USB host. The driver (will)implement a USB host controller (similar to UHCI, OHCI or EHCI)for which the root hub is the radio...To reiterate: it is a USBcontroller that is connected via USB instead of PCI.
WINET: some HW provide a WiNET interface (IP over UWB). Thispackage provides a driver for it (it looks like a networkinterface, winetX). The driver detects when there is a link up fortheir type and kick into gear.

DWA: Device Wired Adaptor, a Wireless USB hub for wired devices¶

These are the complement to HWAs. They are a USB host for connectingwired devices, but it is connected to your PC connected via WirelessUSB. To the system it looks like yet another USB host. To the untrainedeye, it looks like a hub that connects upstream wirelessly.

We still offer no support for this; however, it should share a lot ofcode with the HWA-RC driver; there is a bunch of factorization work thathas been done to support that in upcoming releases.

WHCI: Wireless Host Controller Interface, the PCI WUSB host adapter¶

This is your usual PCI device that implements WHCI. Similar in conceptto EHCI, it allows your wireless USB devices (including DWAs) to connectto your host via a PCI interface. As in the case of the HWA, it has aRadio Control interface and the WUSB Host Controller interface per se.

There is still no driver support for this, but will be in upcomingreleases.

The UWB stack¶

The main mission of the UWB stack is to keep a tally of which devicesare in radio proximity to allow drivers to connect to them. As well, itprovides an API for controlling the local radio controllers (RCs fromnow on), such as to start/stop beaconing, scan, allocate bandwidth, etc.

Devices and hosts: the basic structure¶

The main building block here is the UWB device (struct uwb_dev). Foreach device that pops up in radio presence (ie: the UWB host receives abeacon from it) you get a struct uwb_dev that will show up in/sys/bus/uwb/devices.

For each RC that is detected, a new struct uwb_rc and struct uwb_dev arecreated. An entry is also created in /sys/class/uwb_rc for each RC.

Each RC driver is implemented by a separate driver that plugs into theinterface that the UWB stack provides through a struct uwb_rc_ops. Thespec creators have been nice enough to make the message format the samefor HWA and WHCI RCs, so the driver is really a very thin transport thatmoves the requests from the UWB API to the device [/uwb_rc_ops->cmd()/]and sends the replies and notifications back to the API[/uwb_rc_neh_grok()/]. Notifications are handled to the UWB daemon, thatis chartered, among other things, to keep the tab of how the UWB radioneighborhood looks, creating and destroying devices as they show up ordisappear.

Command execution is very simple: a command block is sent and a eventblock or reply is expected back. For sending/receiving command/events, ahandle called /neh/ (Notification/Event Handle) is opened with/uwb_rc_neh_open()/.

The HWA-RC (USB dongle) driver (drivers/uwb/hwa-rc.c) does this job forthe USB connected HWA. Eventually, drivers/whci-rc.c will do the samefor the PCI connected WHCI controller.

Host Controller life cycle¶

So let's say we connect a dongle to the system: it is detected andfirmware uploaded if needed [for Intel's i1480/drivers/uwb/ptc/usb.c:ptc_usb_probe()/] and then it is reenumerated.Now we have a real HWA device connected and/drivers/uwb/hwa-rc.c:hwarc_probe()/ picks it up, that will set up theWire-Adaptor environment and then suck it into the UWB stack's vision ofthe world [/drivers/uwb/lc-rc.c:uwb_rc_add()/].

[*] The stack should put a new RC to scan for devices[/uwb_rc_scan()/] so it finds what's available around and tries toconnect to them, but this is policy stuff and should be drivenfrom user space. As of now, the operator is expected to do itmanually; see the release notes for documentation on the procedure.

When a dongle is disconnected, /drivers/uwb/hwa-rc.c:hwarc_disconnect()/takes time of tearing everything down safely (or not...).

On the air: beacons and enumerating the radio neighborhood¶

So assuming we have devices

Drivers UWB Radio Controller