diff options
Diffstat (limited to 'Documentation/usb')
-rw-r--r-- | Documentation/usb/WUSB-Design-overview.txt | 448 | ||||
-rw-r--r-- | Documentation/usb/anchors.txt | 29 | ||||
-rw-r--r-- | Documentation/usb/auerswald.txt | 30 | ||||
-rw-r--r-- | Documentation/usb/authorization.txt | 2 | ||||
-rw-r--r-- | Documentation/usb/gadget_serial.txt | 35 | ||||
-rw-r--r-- | Documentation/usb/misc_usbsevseg.txt | 46 | ||||
-rw-r--r-- | Documentation/usb/persist.txt | 7 | ||||
-rw-r--r-- | Documentation/usb/power-management.txt | 15 | ||||
-rw-r--r-- | Documentation/usb/uhci.txt | 165 | ||||
-rw-r--r-- | Documentation/usb/wusb-cbaf | 139 |
10 files changed, 704 insertions, 212 deletions
diff --git a/Documentation/usb/WUSB-Design-overview.txt b/Documentation/usb/WUSB-Design-overview.txt new file mode 100644 index 00000000000..4c3d62c7843 --- /dev/null +++ b/Documentation/usb/WUSB-Design-overview.txt @@ -0,0 +1,448 @@ + +Linux UWB + Wireless USB + WiNET + + (C) 2005-2006 Intel Corporation + Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License version + 2 as published by the Free Software Foundation. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301, USA. + + +Please visit http://bughost.org/thewiki/Design-overview.txt-1.8 for +updated content. + + * Design-overview.txt-1.8 + +This code implements a Ultra Wide Band stack for Linux, as well as +drivers for the the USB based UWB radio controllers defined in the +Wireless USB 1.0 specification (including Wireless USB host controller +and an Intel WiNET controller). + + 1. Introduction + 1. HWA: Host Wire adapters, your Wireless USB dongle + + 2. DWA: Device Wired Adaptor, a Wireless USB hub for wired + devices + 3. WHCI: Wireless Host Controller Interface, the PCI WUSB host + adapter + 2. The UWB stack + 1. Devices and hosts: the basic structure + + 2. Host Controller life cycle + + 3. On the air: beacons and enumerating the radio neighborhood + + 4. Device lists + 5. Bandwidth allocation + + 3. Wireless USB Host Controller drivers + + 4. Glossary + + + Introduction + +UWB is a wide-band communication protocol that is to serve also as the +low-level protocol for others (much like TCP sits on IP). Currently +these others are Wireless USB and TCP/IP, but seems Bluetooth and +Firewire/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 being +negotiated w/ regulators, so watch for changes). That band is divided in +a bunch of ~1.5 GHz wide channels (or band groups) composed of three +subbands/subchannels (528 MHz each). Each channel is independent of each +other, so you could consider them different "busses". Initially this +driver considers them all a single one. + +Radio time is divided in 65536 us long /superframes/, each one divided +in 256 256us long /MASs/ (Media Allocation Slots), which are the basic +time/media allocation units for transferring data. At the beginning of +each superframe there is a Beacon Period (BP), where every device +transmit its beacon on a single MAS. The length of the BP depends on how +many devices are present and the length of their beacons. + +Devices have a MAC (fixed, 48 bit address) and a device (changeable, 16 +bit address) and send periodic beacons to advertise themselves and pass +info on what they are and do. They advertise their capabilities and a +bunch of other stuff. + +The different logical parts of this driver are: + + * + + *UWB*: the Ultra-Wide-Band stack -- manages the radio and + associated spectrum to allow for devices sharing it. Allows to + control bandwidth assingment, 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 to + do the actual WUSB. + + + HWA: Host Wire adapters, your Wireless USB dongle + +WUSB also defines a device called a Host Wire Adaptor (HWA), which in +mere terms is a USB dongle that enables your PC to have UWB and Wireless +USB. 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 the + Ultra-Wide-Band radio controller. The driver for this implements a + USB-based UWB Radio Controller to the UWB stack. + + * + + *HC*: the wireless USB host controller. It looks like a USB host + whose 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 USB + controller that is connected via USB instead of PCI. + + * + + *WINET*: some HW provide a WiNET interface (IP over UWB). This + package provides a driver for it (it looks like a network + interface, winetX). The driver detects when there is a link up for + their 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 connecting +wired devices, but it is connected to your PC connected via Wireless +USB. To the system it looks like yet another USB host. To the untrained +eye, it looks like a hub that connects upstream wirelessly. + +We still offer no support for this; however, it should share a lot of +code with the HWA-RC driver; there is a bunch of factorization work that +has 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 concept +to EHCI, it allows your wireless USB devices (including DWAs) to connect +to your host via a PCI interface. As in the case of the HWA, it has a +Radio Control interface and the WUSB Host Controller interface per se. + +There is still no driver support for this, but will be in upcoming +releases. + + + The UWB stack + +The main mission of the UWB stack is to keep a tally of which devices +are in radio proximity to allow drivers to connect to them. As well, it +provides an API for controlling the local radio controllers (RCs from +now 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). For +each device that pops up in radio presence (ie: the UWB host receives a +beacon from it) you get a struct uwb_dev that will show up in +/sys/class/uwb and in /sys/bus/uwb/devices. + +For each RC that is detected, a new struct uwb_rc is created. In turn, a +RC is also a device, so they also show in /sys/class/uwb and +/sys/bus/uwb/devices, but at the same time, only radio controllers show +up in /sys/class/uwb_rc. + + * + + [*] The reason for RCs being also devices is that not only we can + see them while enumerating the system device tree, but also on the + radio (their beacons and stuff), so the handling has to be + likewise to that of a device. + +Each RC driver is implemented by a separate driver that plugs into the +interface that the UWB stack provides through a struct uwb_rc_ops. The +spec creators have been nice enough to make the message format the same +for HWA and WHCI RCs, so the driver is really a very thin transport that +moves 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, that +is chartered, among other things, to keep the tab of how the UWB radio +neighborhood looks, creating and destroying devices as they show up or +dissapear. + +Command execution is very simple: a command block is sent and a event +block or reply is expected back. For sending/receiving command/events, a +handle 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 for +the USB connected HWA. Eventually, drivers/whci-rc.c will do the same +for the PCI connected WHCI controller. + + + Host Controller life cycle + +So let's say we connect a dongle to the system: it is detected and +firmware 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 the +Wire-Adaptor environment and then suck it into the UWB stack's vision of +the 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 to + connect to them, but this is policy stuff and should be driven + from user space. As of now, the operator is expected to do it + manually; 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 and we have agreed for a channel to connect +on (let's say 9), we put the new RC to beacon: + + * + + $ echo 9 0 > /sys/class/uwb_rc/uwb0/beacon + +Now it is visible. If there were other devices in the same radio channel +and beacon group (that's what the zero is for), the dongle's radio +control interface will send beacon notifications on its +notification/event endpoint (NEEP). The beacon notifications are part of +the event stream that is funneled into the API with +/drivers/uwb/neh.c:uwb_rc_neh_grok()/ and delivered to the UWBD, the UWB +daemon through a notification list. + +UWBD wakes up and scans the event list; finds a beacon and adds it to +the BEACON CACHE (/uwb_beca/). If he receives a number of beacons from +the same device, he considers it to be 'onair' and creates a new device +[/drivers/uwb/lc-dev.c:uwbd_dev_onair()/]. Similarly, when no beacons +are received in some time, the device is considered gone and wiped out +[uwbd calls periodically /uwb/beacon.c:uwb_beca_purge()/ that will purge +the beacon cache of dead devices]. + + + Device lists + +All UWB devices are kept in the list of the struct bus_type uwb_bus. + + + Bandwidth allocation + +The UWB stack maintains a local copy of DRP availability through +processing of incoming *DRP Availability Change* notifications. This +local copy is currently used to present the current bandwidth +availability to the user through the sysfs file +/sys/class/uwb_rc/uwbx/bw_avail. In the future the bandwidth +availability information will be used by the bandwidth reservation +routines. + +The bandwidth reservation routines are in progress and are thus not +present in the current release. When completed they will enable a user +to initiate DRP reservation requests through interaction with sysfs. DRP +reservation requests from remote UWB devices will also be handled. The +bandwidth management done by the UWB stack will include callbacks to the +higher layers will enable the higher layers to use the reservations upon +completion. [Note: The bandwidth reservation work is in progress and +subject to change.] + + + Wireless USB Host Controller drivers + +*WARNING* This section needs a lot of work! + +As explained above, there are three different types of HCs in the WUSB +world: HWA-HC, DWA-HC and WHCI-HC. + +HWA-HC and DWA-HC share that they are Wire-Adapters (USB or WUSB +connected controllers), and their transfer management system is almost +identical. So is their notification delivery system. + +HWA-HC and WHCI-HC share that they are both WUSB host controllers, so +they have to deal with WUSB device life cycle and maintenance, wireless +root-hub + +HWA exposes a Host Controller interface (HWA-HC 0xe0/02/02). This has +three endpoints (Notifications, Data Transfer In and Data Transfer +Out--known as NEP, DTI and DTO in the code). + +We reserve UWB bandwidth for our Wireless USB Cluster, create a Cluster +ID and tell the HC to use all that. Then we start it. This means the HC +starts sending MMCs. + + * + + The MMCs are blocks of data defined somewhere in the WUSB1.0 spec + that define a stream in the UWB channel time allocated for sending + WUSB IEs (host to device commands/notifications) and Device + Notifications (device initiated to host). Each host defines a + unique Wireless USB cluster through MMCs. Devices can connect to a + single cluster at the time. The IEs are Information Elements, and + among them are the bandwidth allocations that tell each device + when can they transmit or receive. + +Now it all depends on external stimuli. + +*New device connection* + +A new device pops up, it scans the radio looking for MMCs that give out +the existence of Wireless USB channels. Once one (or more) are found, +selects which one to connect to. Sends a /DN_Connect/ (device +notification connect) during the DNTS (Device Notification Time +Slot--announced in the MMCs + +HC picks the /DN_Connect/ out (nep module sends to notif.c for delivery +into /devconnect/). This process starts the authentication process for +the device. First we allocate a /fake port/ and assign an +unauthenticated address (128 to 255--what we really do is +0x80 | fake_port_idx). We fiddle with the fake port status and /khubd/ +sees a new connection, so he moves on to enable the fake port with a reset. + +So now we are in the reset path -- we know we have a non-yet enumerated +device with an unauthorized address; we ask user space to authenticate +(FIXME: not yet done, similar to bluetooth pairing), then we do the key +exchange (FIXME: not yet done) and issue a /set address 0/ to bring the +device to the default state. Device is authenticated. + +From here, the USB stack takes control through the usb_hcd ops. khubd +has seen the port status changes, as we have been toggling them. It will +start enumerating and doing transfers through usb_hcd->urb_enqueue() to +read descriptors and move our data. + +*Device life cycle and keep alives* + +Everytime there is a succesful transfer to/from a device, we update a +per-device activity timestamp. If not, every now and then we check and +if the activity timestamp gets old, we ping the device by sending it a +Keep Alive IE; it responds with a /DN_Alive/ pong during the DNTS (this +arrives to us as a notification through +devconnect.c:wusb_handle_dn_alive(). If a device times out, we +disconnect it from the system (cleaning up internal information and +toggling the bits in the fake hub port, which kicks khubd into removing +the rest of the stuff). + +This is done through devconnect:__wusb_check_devs(), which will scan the +device list looking for whom needs refreshing. + +If the device wants to disconnect, it will either die (ugly) or send a +/DN_Disconnect/ that will prompt a disconnection from the system. + +*Sending and receiving data* + +Data is sent and received through /Remote Pipes/ (rpipes). An rpipe is +/aimed/ at an endpoint in a WUSB device. This is the same for HWAs and +DWAs. + +Each HC has a number of rpipes and buffers that can be assigned to them; +when doing a data transfer (xfer), first the rpipe has to be aimed and +prepared (buffers assigned), then we can start queueing requests for +data in or out. + +Data buffers have to be segmented out before sending--so we send first a +header (segment request) and then if there is any data, a data buffer +immediately after to the DTI interface (yep, even the request). If our +buffer is bigger than the max segment size, then we just do multiple +requests. + +[This sucks, because doing USB scatter gatter in Linux is resource +intensive, if any...not that the current approach is not. It just has to +be cleaned up a lot :)]. + +If reading, we don't send data buffers, just the segment headers saying +we want to read segments. + +When the xfer is executed, we receive a notification that says data is +ready in the DTI endpoint (handled through +xfer.c:wa_handle_notif_xfer()). In there we read from the DTI endpoint a +descriptor that gives us the status of the transfer, its identification +(given when we issued it) and the segment number. If it was a data read, +we issue another URB to read into the destination buffer the chunk of +data coming out of the remote endpoint. Done, wait for the next guy. The +callbacks for the URBs issued from here are the ones that will declare +the xfer complete at some point and call it's callback. + +Seems simple, but the implementation is not trivial. + + * + + *WARNING* Old!! + +The main xfer descriptor, wa_xfer (equivalent to a URB) contains an +array of segments, tallys on segments and buffers and callback +information. Buried in there is a lot of URBs for executing the segments +and buffer transfers. + +For OUT xfers, there is an array of segments, one URB for each, another +one of buffer URB. When submitting, we submit URBs for segment request +1, buffer 1, segment 2, buffer 2...etc. Then we wait on the DTI for xfer +result data; when all the segments are complete, we call the callback to +finalize the transfer. + +For IN xfers, we only issue URBs for the segments we want to read and +then wait for the xfer result data. + +*URB mapping into xfers* + +This is done by hwahc_op_urb_[en|de]queue(). In enqueue() we aim an +rpipe to the endpoint where we have to transmit, create a transfer +context (wa_xfer) and submit it. When the xfer is done, our callback is +called and we assign the status bits and release the xfer resources. + +In dequeue() we are basically cancelling/aborting the transfer. We issue +a xfer abort request to the HC, cancell all the URBs we had submitted +and not yet done and when all that is done, the xfer callback will be +called--this will call the URB callback. + + + Glossary + +*DWA* -- Device Wire Adapter + +USB host, wired for downstream devices, upstream connects wirelessly +with Wireless USB. + +*EVENT* -- Response to a command on the NEEP + +*HWA* -- Host Wire Adapter / USB dongle for UWB and Wireless USB + +*NEH* -- Notification/Event Handle + +Handle/file descriptor for receiving notifications or events. The WA +code requires you to get one of this to listen for notifications or +events on the NEEP. + +*NEEP* -- Notification/Event EndPoint + +Stuff related to the management of the first endpoint of a HWA USB +dongle that is used to deliver an stream of events and notifications to +the host. + +*NOTIFICATION* -- Message coming in the NEEP as response to something. + +*RC* -- Radio Control + +Design-overview.txt-1.8 (last edited 2006-11-04 12:22:24 by +InakyPerezGonzalez) + diff --git a/Documentation/usb/anchors.txt b/Documentation/usb/anchors.txt index 7304bcf5a30..6f24f566955 100644 --- a/Documentation/usb/anchors.txt +++ b/Documentation/usb/anchors.txt @@ -42,9 +42,38 @@ This function kills all URBs associated with an anchor. The URBs are called in the reverse temporal order they were submitted. This way no data can be reordered. +usb_unlink_anchored_urbs() +-------------------------- + +This function unlinks all URBs associated with an anchor. The URBs +are processed in the reverse temporal order they were submitted. +This is similar to usb_kill_anchored_urbs(), but it will not sleep. +Therefore no guarantee is made that the URBs have been unlinked when +the call returns. They may be unlinked later but will be unlinked in +finite time. + +usb_scuttle_anchored_urbs() +--------------------------- + +All URBs of an anchor are unanchored en masse. + usb_wait_anchor_empty_timeout() ------------------------------- This function waits for all URBs associated with an anchor to finish or a timeout, whichever comes first. Its return value will tell you whether the timeout was reached. + +usb_anchor_empty() +------------------ + +Returns true if no URBs are associated with an anchor. Locking +is the caller's responsibility. + +usb_get_from_anchor() +--------------------- + +Returns the oldest anchored URB of an anchor. The URB is unanchored +and returned with a reference. As you may mix URBs to several +destinations in one anchor you have no guarantee the chronologically +first submitted URB is returned.
\ No newline at end of file diff --git a/Documentation/usb/auerswald.txt b/Documentation/usb/auerswald.txt deleted file mode 100644 index 7ee4d8f6911..00000000000 --- a/Documentation/usb/auerswald.txt +++ /dev/null @@ -1,30 +0,0 @@ - Auerswald USB kernel driver - =========================== - -What is it? What can I do with it? -================================== -The auerswald USB kernel driver connects your linux 2.4.x -system to the auerswald usb-enabled devices. - -There are two types of auerswald usb devices: -a) small PBX systems (ISDN) -b) COMfort system telephones (ISDN) - -The driver installation creates the devices -/dev/usb/auer0..15. These devices carry a vendor- -specific protocol. You may run all auerswald java -software on it. The java software needs a native -library "libAuerUsbJNINative.so" installed on -your system. This library is available from -auerswald and shipped as part of the java software. - -You may create the devices with: - mknod -m 666 /dev/usb/auer0 c 180 112 - ... - mknod -m 666 /dev/usb/auer15 c 180 127 - -Future plans -============ -- Connection to ISDN4LINUX (the hisax interface) - -The maintainer of this driver is wolfgang@iksw-muees.de diff --git a/Documentation/usb/authorization.txt b/Documentation/usb/authorization.txt index 2af40060949..381b22ee783 100644 --- a/Documentation/usb/authorization.txt +++ b/Documentation/usb/authorization.txt @@ -8,7 +8,7 @@ not) in a system. This feature will allow you to implement a lock-down of USB devices, fully controlled by user space. As of now, when a USB device is connected it is configured and -it's interfaces inmediately made available to the users. With this +its interfaces are immediately made available to the users. With this modification, only if root authorizes the device to be configured will then it be possible to use it. diff --git a/Documentation/usb/gadget_serial.txt b/Documentation/usb/gadget_serial.txt index 815f5c2301f..9b22bd14c34 100644 --- a/Documentation/usb/gadget_serial.txt +++ b/Documentation/usb/gadget_serial.txt @@ -1,6 +1,7 @@ Linux Gadget Serial Driver v2.0 11/20/2004 + (updated 8-May-2008 for v2.3) License and Disclaimer @@ -31,7 +32,7 @@ Prerequisites ------------- Versions of the gadget serial driver are available for the 2.4 Linux kernels, but this document assumes you are using -version 2.0 or later of the gadget serial driver in a 2.6 +version 2.3 or later of the gadget serial driver in a 2.6 Linux kernel. This document assumes that you are familiar with Linux and @@ -40,6 +41,12 @@ standard utilities, use minicom and HyperTerminal, and work with USB and serial devices. It also assumes you configure the Linux gadget and usb drivers as modules. +With version 2.3 of the driver, major and minor device nodes are +no longer statically defined. Your Linux based system should mount +sysfs in /sys, and use "mdev" (in Busybox) or "udev" to make the +/dev nodes matching the sysfs /sys/class/tty files. + + Overview -------- @@ -104,15 +111,8 @@ driver. All this are listed under "USB Gadget Support" when configuring the kernel. Then rebuild and install the kernel or modules. -The gadget serial driver uses major number 127, for now. So you -will need to create a device node for it, like this: - - mknod /dev/ttygserial c 127 0 - -You only need to do this once. - Then you must load the gadget serial driver. To load it as an -ACM device, do this: +ACM device (recommended for interoperability), do this: modprobe g_serial use_acm=1 @@ -125,6 +125,23 @@ controller driver. This must be done each time you reboot the gadget side Linux system. You can add this to the start up scripts, if desired. +Your system should use mdev (from busybox) or udev to make the +device nodes. After this gadget driver has been set up you should +then see a /dev/ttyGS0 node: + + # ls -l /dev/ttyGS0 | cat + crw-rw---- 1 root root 253, 0 May 8 14:10 /dev/ttyGS0 + # + +Note that the major number (253, above) is system-specific. If +you need to create /dev nodes by hand, the right numbers to use +will be in the /sys/class/tty/ttyGS0/dev file. + +When you link this gadget driver early, perhaps even statically, +you may want to set up an /etc/inittab entry to run "getty" on it. +The /dev/ttyGS0 line should work like most any other serial port. + + If gadget serial is loaded as an ACM device you will want to use either the Windows or Linux ACM driver on the host side. If gadget serial is loaded as a bulk in/out device, you will want to use the diff --git a/Documentation/usb/misc_usbsevseg.txt b/Documentation/usb/misc_usbsevseg.txt new file mode 100644 index 00000000000..0f6be4f9930 --- /dev/null +++ b/Documentation/usb/misc_usbsevseg.txt @@ -0,0 +1,46 @@ +USB 7-Segment Numeric Display +Manufactured by Delcom Engineering + +Device Information +------------------ +USB VENDOR_ID 0x0fc5 +USB PRODUCT_ID 0x1227 +Both the 6 character and 8 character displays have PRODUCT_ID, +and according to Delcom Engineering no queryable information +can be obtained from the device to tell them apart. + +Device Modes +------------ +By default, the driver assumes the display is only 6 characters +The mode for 6 characters is: + MSB 0x06; LSB 0x3f +For the 8 character display: + MSB 0x08; LSB 0xff +The device can accept "text" either in raw, hex, or ascii textmode. +raw controls each segment manually, +hex expects a value between 0-15 per character, +ascii expects a value between '0'-'9' and 'A'-'F'. +The default is ascii. + +Device Operation +---------------- +1. Turn on the device: + echo 1 > /sys/bus/usb/.../powered +2. Set the device's mode: + echo $mode_msb > /sys/bus/usb/.../mode_msb + echo $mode_lsb > /sys/bus/usb/.../mode_lsb +3. Set the textmode: + echo $textmode > /sys/bus/usb/.../textmode +4. set the text (for example): + echo "123ABC" > /sys/bus/usb/.../text (ascii) + echo "A1B2" > /sys/bus/usb/.../text (ascii) + echo -ne "\x01\x02\x03" > /sys/bus/usb/.../text (hex) +5. Set the decimal places. + The device has either 6 or 8 decimal points. + to set the nth decimal place calculate 10 ** n + and echo it in to /sys/bus/usb/.../decimals + To set multiple decimals points sum up each power. + For example, to set the 0th and 3rd decimal place + echo 1001 > /sys/bus/usb/.../decimals + + diff --git a/Documentation/usb/persist.txt b/Documentation/usb/persist.txt index d56cb1a1155..074b159b77c 100644 --- a/Documentation/usb/persist.txt +++ b/Documentation/usb/persist.txt @@ -81,8 +81,11 @@ re-enumeration shows that the device now attached to that port has the same descriptors as before, including the Vendor and Product IDs, then the kernel continues to use the same device structure. In effect, the kernel treats the device as though it had merely been reset instead of -unplugged. The same thing happens if the host controller is in the -expected state but a USB device was unplugged and then replugged. +unplugged. + +The same thing happens if the host controller is in the expected state +but a USB device was unplugged and then replugged, or if a USB device +fails to carry out a normal resume. If no device is now attached to the port, or if the descriptors are different from what the kernel remembers, then the treatment is what diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index b2fc4d4a991..e48ea1d5101 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt @@ -350,12 +350,12 @@ without holding the mutex. There also are a couple of utility routines drivers can use: - usb_autopm_enable() sets pm_usage_cnt to 1 and then calls - usb_autopm_set_interface(), which will attempt an autoresume. - - usb_autopm_disable() sets pm_usage_cnt to 0 and then calls + usb_autopm_enable() sets pm_usage_cnt to 0 and then calls usb_autopm_set_interface(), which will attempt an autosuspend. + usb_autopm_disable() sets pm_usage_cnt to 1 and then calls + usb_autopm_set_interface(), which will attempt an autoresume. + The conventional usage pattern is that a driver calls usb_autopm_get_interface() in its open routine and usb_autopm_put_interface() in its close or release routine. But @@ -436,7 +436,12 @@ post_reset; the USB core guarantees that this is true of internal suspend/resume events as well. If a driver wants to block all suspend/resume calls during some -critical section, it can simply acquire udev->pm_mutex. +critical section, it can simply acquire udev->pm_mutex. Note that +calls to resume may be triggered indirectly. Block IO due to memory +allocations can make the vm subsystem resume a device. Thus while +holding this lock you must not allocate memory with GFP_KERNEL or +GFP_NOFS. + Alternatively, if the critical section might call some of the usb_autopm_* routines, the driver can avoid deadlock by doing: diff --git a/Documentation/usb/uhci.txt b/Documentation/usb/uhci.txt deleted file mode 100644 index 2f25952c86c..00000000000 --- a/Documentation/usb/uhci.txt +++ /dev/null @@ -1,165 +0,0 @@ -Specification and Internals for the New UHCI Driver (Whitepaper...) - - brought to you by - - Georg Acher, acher@in.tum.de (executive slave) (base guitar) - Deti Fliegl, deti@fliegl.de (executive slave) (lead voice) - Thomas Sailer, sailer@ife.ee.ethz.ch (chief consultant) (cheer leader) - - $Id: README.uhci,v 1.1 1999/12/14 14:03:02 fliegl Exp $ - -This document and the new uhci sources can be found on - http://hotswap.in.tum.de/usb - -1. General issues - -1.1 Why a new UHCI driver, we already have one?!? - -Correct, but its internal structure got more and more mixed up by the (still -ongoing) efforts to get isochronous transfers (ISO) to work. -Since there is an increasing need for reliable ISO-transfers (especially -for USB-audio needed by TS and for a DAB-USB-Receiver build by GA and DF), -this state was a bit unsatisfying in our opinion, so we've decided (based -on knowledge and experiences with the old UHCI driver) to start -from scratch with a new approach, much simpler but at the same time more -powerful. -It is inspired by the way Win98/Win2000 handles USB requests via URBs, -but it's definitely 100% free of MS-code and doesn't crash while -unplugging an used ISO-device like Win98 ;-) -Some code for HW setup and root hub management was taken from the -original UHCI driver, but heavily modified to fit into the new code. -The invention of the basic concept, and major coding were completed in two -days (and nights) on the 16th and 17th of October 1999, now known as the -great USB-October-Revolution started by GA, DF, and TS ;-) - -Since the concept is in no way UHCI dependent, we hope that it will also be -transferred to the OHCI-driver, so both drivers share a common API. - -1.2. Advantages and disadvantages - -+ All USB transfer types work now! -+ Asynchronous operation -+ Simple, but powerful interface (only two calls for start and cancel) -+ Easy migration to the new API, simplified by a compatibility API -+ Simple usage of ISO transfers -+ Automatic linking of requests -+ ISO transfers allow variable length for each frame and striping -+ No CPU dependent and non-portable atomic memory access, no asm()-inlines -+ Tested on x86 and Alpha - -- Rewriting for ISO transfers needed - -1.3. Is there some compatibility to the old API? - -Yes, but only for control, bulk and interrupt transfers. We've implemented -some wrapper calls for these transfer types. The usbcore works fine with -these wrappers. For ISO there's no compatibility, because the old ISO-API -and its semantics were unnecessary complicated in our opinion. - -1.4. What's really working? - -As said above, CTRL and BULK already work fine even with the wrappers, -so legacy code wouldn't notice the change. -Regarding to Thomas, ISO transfers now run stable with USB audio. -INT transfers (e.g. mouse driver) work fine, too. - -1.5. Are there any bugs? - -No ;-) -Hm... -Well, of course this implementation needs extensive testing on all available -hardware, but we believe that any fixes shouldn't harm the overall concept. - -1.6. What should be done next? - -A large part of the request handling seems to be identical for UHCI and -OHCI, so it would be a good idea to extract the common parts and have only -the HW specific stuff in uhci.c. Furthermore, all other USB device drivers -should need URBification, if they use isochronous or interrupt transfers. -One thing missing in the current implementation (and the old UHCI driver) -is fair queueing for BULK transfers. Since this would need (in principle) -the alteration of already constructed TD chains (to switch from depth to -breadth execution), another way has to be found. Maybe some simple -heuristics work with the same effect. - ---------------------------------------------------------------------------- - -2. Internal structure and mechanisms - -To get quickly familiar with the internal structures, here's a short -description how the new UHCI driver works. However, the ultimate source of -truth is only uhci.c! - -2.1. Descriptor structure (QHs and TDs) - -During initialization, the following skeleton is allocated in init_skel: - - framespecific | common chain - -framelist[] -[ 0 ]-----> TD --> TD -------\ -[ 1 ]-----> TD --> TD --------> TD ----> QH -------> QH -------> QH ---> NULL - ... TD --> TD -------/ -[1023]-----> TD --> TD ------/ - - ^^ ^^ ^^ ^^ ^^ ^^ - 1024 TDs for 7 TDs for 1 TD for Start of Start of End Chain - ISO INT (2-128ms) 1ms-INT CTRL Chain BULK Chain - -For each CTRL or BULK transfer a new QH is allocated and the containing data -transfers are appended as (vertical) TDs. After building the whole QH with its -dangling TDs, the QH is inserted before the BULK Chain QH (for CTRL) or -before the End Chain QH (for BULK). Since only the QH->next pointers are -affected, no atomic memory operation is required. The three QHs in the -common chain are never equipped with TDs! - -For ISO or INT, the TD for each frame is simply inserted into the appropriate -ISO/INT-TD-chain for the desired frame. The 7 skeleton INT-TDs are scattered -among the 1024 frames similar to the old UHCI driver. - -For CTRL/BULK/ISO, the last TD in the transfer has the IOC-bit set. For INT, -every TD (there is only one...) has the IOC-bit set. - -Besides the data for the UHCI controller (2 or 4 32bit words), the descriptors -are double-linked through the .vertical and .horizontal elements in the -SW data of the descriptor (using the double-linked list structures and -operations), but SW-linking occurs only in closed domains, i.e. for each of -the 1024 ISO-chains and the 8 INT-chains there is a closed cycle. This -simplifies all insertions and unlinking operations and avoids costly -bus_to_virt()-calls. - -2.2. URB structure and linking to QH/TDs - -During assembly of the QH and TDs of the requested action, these descriptors -are stored in urb->urb_list, so the allocated QH/TD descriptors are bound to -this URB. -If the assembly was successful and the descriptors were added to the HW chain, -the corresponding URB is inserted into a global URB list for this controller. -This list stores all pending URBs. - -2.3. Interrupt processing - -Since UHCI provides no means to directly detect completed transactions, the -following is done in each UHCI interrupt (uhci_interrupt()): - -For each URB in the pending queue (process_urb()), the ACTIVE-flag of the -associated TDs are processed (depending on the transfer type -process_{transfer|interrupt|iso}()). If the TDs are not active anymore, -they indicate the completion of the transaction and the status is calculated. -Inactive QH/TDs are removed from the HW chain (since the host controller -already removed the TDs from the QH, no atomic access is needed) and -eventually the URB is marked as completed (OK or errors) and removed from the -pending queue. Then the next linked URB is submitted. After (or immediately -before) that, the completion handler is called. - -2.4. Unlinking URBs - -First, all QH/TDs stored in the URB are unlinked from the HW chain. -To ensure that the host controller really left a vertical TD chain, we -wait for one frame. After that, the TDs are physically destroyed. - -2.5. URB linking and the consequences - -Since URBs can be linked and the corresponding submit_urb is called in -the UHCI-interrupt, all work associated with URB/QH/TD assembly has to be -interrupt save. This forces kmalloc to use GFP_ATOMIC in the interrupt. diff --git a/Documentation/usb/wusb-cbaf b/Documentation/usb/wusb-cbaf new file mode 100644 index 00000000000..2e78b70f3ad --- /dev/null +++ b/Documentation/usb/wusb-cbaf @@ -0,0 +1,139 @@ +#! /bin/bash +# + +set -e + +progname=$(basename $0) +function help +{ + cat <<EOF +Usage: $progname COMMAND DEVICEs [ARGS] + +Command for manipulating the pairing/authentication credentials of a +Wireless USB device that supports wired-mode Cable-Based-Association. + +Works in conjunction with the wusb-cba.ko driver from http://linuxuwb.org. + + +DEVICE + + sysfs path to the device to authenticate; for example, both this + guys are the same: + + /sys/devices/pci0000:00/0000:00:1d.7/usb1/1-4/1-4.4/1-4.4:1.1 + /sys/bus/usb/drivers/wusb-cbaf/1-4.4:1.1 + +COMMAND/ARGS are + + start + + Start a WUSB host controller (by setting up a CHID) + + set-chid DEVICE HOST-CHID HOST-BANDGROUP HOST-NAME + + Sets host information in the device; after this you can call the + get-cdid to see how does this device report itself to us. + + get-cdid DEVICE + + Get the device ID associated to the HOST-CHDI we sent with + 'set-chid'. We might not know about it. + + set-cc DEVICE + + If we allow the device to connect, set a random new CDID and CK + (connection key). Device saves them for the next time it wants to + connect wireless. We save them for that next time also so we can + authenticate the device (when we see the CDID he uses to id + itself) and the CK to crypto talk to it. + +CHID is always 16 hex bytes in 'XX YY ZZ...' form +BANDGROUP is almost always 0001 + +Examples: + + You can default most arguments to '' to get a sane value: + + $ $progname set-chid '' '' '' "My host name" + + A full sequence: + + $ $progname set-chid '' '' '' "My host name" + $ $progname get-cdid '' + $ $progname set-cc '' + +EOF +} + + +# Defaults +# FIXME: CHID should come from a database :), band group from the host +host_CHID="00 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff" +host_band_group="0001" +host_name=$(hostname) + +devs="$(echo /sys/bus/usb/drivers/wusb-cbaf/[0-9]*)" +hdevs="$(for h in /sys/class/uwb_rc/*/wusbhc; do readlink -f $h; done)" + +result=0 +case $1 in + start) + for dev in ${2:-$hdevs} + do + uwb_rc=$(readlink -f $dev/uwb_rc) + if cat $uwb_rc/beacon | grep -q -- "-1" + then + echo 13 0 > $uwb_rc/beacon + echo I: started beaconing on ch 13 on $(basename $uwb_rc) >&2 + fi + echo $host_CHID > $dev/wusb_chid + echo I: started host $(basename $dev) >&2 + done + ;; + stop) + for dev in ${2:-$hdevs} + do + echo 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > $dev/wusb_chid + echo I: stopped host $(basename $dev) >&2 + uwb_rc=$(readlink -f $dev/uwb_rc) + echo -1 | cat > $uwb_rc/beacon + echo I: stopped beaconing on $(basename $uwb_rc) >&2 + done + ;; + set-chid) + shift + for dev in ${2:-$devs}; do + echo "${4:-$host_name}" > $dev/wusb_host_name + echo "${3:-$host_band_group}" > $dev/wusb_host_band_groups + echo ${2:-$host_CHID} > $dev/wusb_chid + done + ;; + get-cdid) + for dev in ${2:-$devs} + do + cat $dev/wusb_cdid + done + ;; + set-cc) + for dev in ${2:-$devs}; do + shift + CDID="$(head --bytes=16 /dev/urandom | od -tx1 -An)" + CK="$(head --bytes=16 /dev/urandom | od -tx1 -An)" + echo "$CDID" > $dev/wusb_cdid + echo "$CK" > $dev/wusb_ck + + echo I: CC set >&2 + echo "CHID: $(cat $dev/wusb_chid)" + echo "CDID:$CDID" + echo "CK: $CK" + done + ;; + help|h|--help|-h) + help + ;; + *) + echo "E: Unknown usage" 1>&2 + help 1>&2 + result=1 +esac +exit $result |