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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/usb
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--Documentation/usb/CREDITS175
-rw-r--r--Documentation/usb/acm.rst132
-rw-r--r--Documentation/usb/authorization.rst132
-rw-r--r--Documentation/usb/chipidea.rst133
-rw-r--r--Documentation/usb/dwc3.rst53
-rw-r--r--Documentation/usb/ehci.rst230
-rw-r--r--Documentation/usb/functionfs.rst68
-rw-r--r--Documentation/usb/gadget-testing.rst934
-rw-r--r--Documentation/usb/gadget_configfs.rst390
-rw-r--r--Documentation/usb/gadget_hid.rst457
-rw-r--r--Documentation/usb/gadget_multi.rst165
-rw-r--r--Documentation/usb/gadget_printer.rst523
-rw-r--r--Documentation/usb/gadget_serial.rst289
-rw-r--r--Documentation/usb/index.rst38
-rw-r--r--Documentation/usb/iuu_phoenix.rst94
-rw-r--r--Documentation/usb/linux-cdc-acm.inf107
-rw-r--r--Documentation/usb/linux.inf66
-rw-r--r--Documentation/usb/mass-storage.rst234
-rw-r--r--Documentation/usb/misc_usbsevseg.rst51
-rw-r--r--Documentation/usb/mtouchusb.rst84
-rw-r--r--Documentation/usb/ohci.rst35
-rw-r--r--Documentation/usb/raw-gadget.rst84
-rw-r--r--Documentation/usb/text_files.rst23
-rw-r--r--Documentation/usb/usb-help.rst17
-rw-r--r--Documentation/usb/usb-serial.rst537
-rw-r--r--Documentation/usb/usbdevfs-drop-permissions.c120
-rw-r--r--Documentation/usb/usbip_protocol.rst411
-rw-r--r--Documentation/usb/usbmon.rst375
28 files changed, 5957 insertions, 0 deletions
diff --git a/Documentation/usb/CREDITS b/Documentation/usb/CREDITS
new file mode 100644
index 000000000..67c59cdc9
--- /dev/null
+++ b/Documentation/usb/CREDITS
@@ -0,0 +1,175 @@
+Credits for the Simple Linux USB Driver:
+
+The following people have contributed to this code (in alphabetical
+order by last name). I'm sure this list should be longer, its
+difficult to maintain, add yourself with a patch if desired.
+
+ Georg Acher <acher@informatik.tu-muenchen.de>
+ David Brownell <dbrownell@users.sourceforge.net>
+ Alan Cox <alan@lxorguk.ukuu.org.uk>
+ Randy Dunlap <randy.dunlap@intel.com>
+ Johannes Erdfelt <johannes@erdfelt.com>
+ Deti Fliegl <deti@fliegl.de>
+ ham <ham@unsuave.com>
+ Bradley M Keryan <keryan@andrew.cmu.edu>
+ Greg Kroah-Hartman <greg@kroah.com>
+ Pavel Machek <pavel@suse.cz>
+ Paul Mackerras <paulus@cs.anu.edu.au>
+ Petko Manlolov <petkan@dce.bg>
+ David E. Nelson <dnelson@jump.net>
+ Vojtech Pavlik <vojtech@suse.cz>
+ Bill Ryder <bryder@sgi.com>
+ Thomas Sailer <sailer@ife.ee.ethz.ch>
+ Gregory P. Smith <greg@electricrain.com>
+ Linus Torvalds <torvalds@linux-foundation.org>
+ Roman Weissgaerber <weissg@vienna.at>
+ <Kazuki.Yasumatsu@fujixerox.co.jp>
+
+Special thanks to:
+
+ Inaky Perez Gonzalez <inaky@peloncho.fis.ucm.es> for starting the
+ Linux USB driver effort and writing much of the larger uusbd driver.
+ Much has been learned from that effort.
+
+ The NetBSD & FreeBSD USB developers. For being on the Linux USB list
+ and offering suggestions and sharing implementation experiences.
+
+Additional thanks to the following companies and people for donations
+of hardware, support, time and development (this is from the original
+THANKS file in Inaky's driver):
+
+ The following corporations have helped us in the development
+ of Linux USB / UUSBD:
+
+ - 3Com GmbH for donating a ISDN Pro TA and supporting me
+ in technical questions and with test equipment. I'd never
+ expect such a great help.
+
+ - USAR Systems provided us with one of their excellent USB
+ Evaluation Kits. It allows us to test the Linux-USB driver
+ for compliance with the latest USB specification. USAR
+ Systems recognized the importance of an up-to-date open
+ Operating System and supports this project with
+ Hardware. Thanks!.
+
+ - Thanks to Intel Corporation for their precious help.
+
+ - We teamed up with Cherry to make Linux the first OS with
+ built-in USB support. Cherry is one of the biggest keyboard
+ makers in the world.
+
+ - CMD Technology, Inc. sponsored us kindly donating a CSA-6700
+ PCI-to-USB Controller Board to test the OHCI implementation.
+
+ - Due to their support to us, Keytronic can be sure that they
+ will sell keyboards to some of the 3 million (at least)
+ Linux users.
+
+ - Many thanks to ing büro h doran [http://www.ibhdoran.com]!
+ It was almost impossible to get a PC backplate USB connector
+ for the motherboard here at Europe (mine, home-made, was
+ quite lousy :). Now I know where to acquire nice USB stuff!
+
+ - Genius Germany donated a USB mouse to test the mouse boot
+ protocol. They've also donated a F-23 digital joystick and a
+ NetMouse Pro. Thanks!
+
+ - AVM GmbH Berlin is supporting the development of the Linux
+ USB driver for the AVM ISDN Controller B1 USB. AVM is a
+ leading manufacturer for active and passive ISDN Controllers
+ and CAPI 2.0-based software. The active design of the AVM B1
+ is open for all OS platforms, including Linux.
+
+ - Thanks to Y-E Data, Inc. for donating their FlashBuster-U
+ USB Floppy Disk Drive, so we could test the bulk transfer
+ code.
+
+ - Many thanks to Logitech for contributing a three axis USB
+ mouse.
+
+ Logitech designs, manufactures and markets
+ Human Interface Devices, having a long history and
+ experience in making devices such as keyboards, mice,
+ trackballs, cameras, loudspeakers and control devices for
+ gaming and professional use.
+
+ Being a recognized vendor and seller for all these devices,
+ they have donated USB mice, a joystick and a scanner, as a
+ way to acknowledge the importance of Linux and to allow
+ Logitech customers to enjoy support in their favorite
+ operating systems and all Linux users to use Logitech and
+ other USB hardware.
+
+ Logitech is official sponsor of the Linux Conference on
+ Feb. 11th 1999 in Vienna, where we'll will present the
+ current state of the Linux USB effort.
+
+ - CATC has provided means to uncover dark corners of the UHCI
+ inner workings with a USB Inspector.
+
+ - Thanks to Entrega for providing PCI to USB cards, hubs and
+ converter products for development.
+
+ - Thanks to ConnectTech for providing a WhiteHEAT usb to
+ serial converter, and the documentation for the device to
+ allow a driver to be written.
+
+ - Thanks to ADMtek for providing Pegasus and Pegasus II
+ evaluation boards, specs and valuable advices during
+ the driver development.
+
+ And thanks go to (hey! in no particular order :)
+
+ - Oren Tirosh <orenti@hishome.net>, for standing so patiently
+ all my doubts'bout USB and giving lots of cool ideas.
+
+ - Jochen Karrer <karrer@wpfd25.physik.uni-wuerzburg.de>, for
+ pointing out mortal bugs and giving advice.
+
+ - Edmund Humemberger <ed@atnet.at>, for it's great work on
+ public relationships and general management stuff for the
+ Linux-USB effort.
+
+ - Alberto Menegazzi <flash@flash.iol.it> is starting the
+ documentation for the UUSBD. Go for it!
+
+ - Ric Klaren <ia_ric@cs.utwente.nl> for doing nice
+ introductory documents (competing with Alberto's :).
+
+ - Christian Groessler <cpg@aladdin.de>, for it's help on those
+ itchy bits ... :)
+
+ - Paul MacKerras for polishing OHCI and pushing me harder for
+ the iMac support, giving improvements and enhancements.
+
+ - Fernando Herrera <fherrera@eurielec.etsit.upm.es> has taken
+ charge of composing, maintaining and feeding the
+ long-awaited, unique and marvelous UUSBD FAQ! Tadaaaa!!!
+
+ - Rasca Gmelch <thron@gmx.de> has revived the raw driver and
+ pointed bugs, as well as started the uusbd-utils package.
+
+ - Peter Dettori <dettori@ozy.dec.com> is uncovering bugs like
+ crazy, as well as making cool suggestions, great :)
+
+ - All the Free Software and Linux community, the FSF & the GNU
+ project, the MIT X consortium, the TeX people ... everyone!
+ You know who you are!
+
+ - Big thanks to Richard Stallman for creating Emacs!
+
+ - The people at the linux-usb mailing list, for reading so
+ many messages :) Ok, no more kidding; for all your advises!
+
+ - All the people at the USB Implementors Forum for their
+ help and assistance.
+
+ - Nathan Myers <ncm@cantrip.org>, for his advice! (hope you
+ liked Cibeles' party).
+
+ - Linus Torvalds, for starting, developing and managing Linux.
+
+ - Mike Smith, Craig Keithley, Thierry Giron and Janet Schank
+ for convincing me USB Standard hubs are not that standard
+ and that's good to allow for vendor specific quirks on the
+ standard hub driver.
diff --git a/Documentation/usb/acm.rst b/Documentation/usb/acm.rst
new file mode 100644
index 000000000..e8bda98e9
--- /dev/null
+++ b/Documentation/usb/acm.rst
@@ -0,0 +1,132 @@
+======================
+Linux ACM driver v0.16
+======================
+
+Copyright (c) 1999 Vojtech Pavlik <vojtech@suse.cz>
+
+Sponsored by SuSE
+
+0. Disclaimer
+~~~~~~~~~~~~~
+This program is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2 of the License, or (at your option)
+any later version.
+
+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., 59
+Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+Should you need to contact me, the author, you can do so either by e-mail -
+mail your message to <vojtech@suse.cz>, or by paper mail: Vojtech Pavlik,
+Ucitelska 1576, Prague 8, 182 00 Czech Republic
+
+For your convenience, the GNU General Public License version 2 is included
+in the package: See the file COPYING.
+
+1. Usage
+~~~~~~~~
+The drivers/usb/class/cdc-acm.c drivers works with USB modems and USB ISDN terminal
+adapters that conform to the Universal Serial Bus Communication Device Class
+Abstract Control Model (USB CDC ACM) specification.
+
+Many modems do, here is a list of those I know of:
+
+ - 3Com OfficeConnect 56k
+ - 3Com Voice FaxModem Pro
+ - 3Com Sportster
+ - MultiTech MultiModem 56k
+ - Zoom 2986L FaxModem
+ - Compaq 56k FaxModem
+ - ELSA Microlink 56k
+
+I know of one ISDN TA that does work with the acm driver:
+
+ - 3Com USR ISDN Pro TA
+
+Some cell phones also connect via USB. I know the following phones work:
+
+ - SonyEricsson K800i
+
+Unfortunately many modems and most ISDN TAs use proprietary interfaces and
+thus won't work with this drivers. Check for ACM compliance before buying.
+
+To use the modems you need these modules loaded::
+
+ usbcore.ko
+ uhci-hcd.ko ohci-hcd.ko or ehci-hcd.ko
+ cdc-acm.ko
+
+After that, the modem[s] should be accessible. You should be able to use
+minicom, ppp and mgetty with them.
+
+2. Verifying that it works
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The first step would be to check /sys/kernel/debug/usb/devices, it should look
+like this::
+
+ T: Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2
+ B: Alloc= 0/900 us ( 0%), #Int= 0, #Iso= 0
+ D: Ver= 1.00 Cls=09(hub ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
+ P: Vendor=0000 ProdID=0000 Rev= 0.00
+ S: Product=USB UHCI Root Hub
+ S: SerialNumber=6800
+ C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr= 0mA
+ I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
+ E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=255ms
+ T: Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 2 Spd=12 MxCh= 0
+ D: Ver= 1.00 Cls=02(comm.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 2
+ P: Vendor=04c1 ProdID=008f Rev= 2.07
+ S: Manufacturer=3Com Inc.
+ S: Product=3Com U.S. Robotics Pro ISDN TA
+ S: SerialNumber=UFT53A49BVT7
+ C: #Ifs= 1 Cfg#= 1 Atr=60 MxPwr= 0mA
+ I: If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=acm
+ E: Ad=85(I) Atr=02(Bulk) MxPS= 64 Ivl= 0ms
+ E: Ad=04(O) Atr=02(Bulk) MxPS= 64 Ivl= 0ms
+ E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=128ms
+ C:* #Ifs= 2 Cfg#= 2 Atr=60 MxPwr= 0mA
+ I: If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=acm
+ E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=128ms
+ I: If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=acm
+ E: Ad=85(I) Atr=02(Bulk) MxPS= 64 Ivl= 0ms
+ E: Ad=04(O) Atr=02(Bulk) MxPS= 64 Ivl= 0ms
+
+The presence of these three lines (and the Cls= 'comm' and 'data' classes)
+is important, it means it's an ACM device. The Driver=acm means the acm
+driver is used for the device. If you see only Cls=ff(vend.) then you're out
+of luck, you have a device with vendor specific-interface::
+
+ D: Ver= 1.00 Cls=02(comm.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 2
+ I: If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=acm
+ I: If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=acm
+
+In the system log you should see::
+
+ usb.c: USB new device connect, assigned device number 2
+ usb.c: kmalloc IF c7691fa0, numif 1
+ usb.c: kmalloc IF c7b5f3e0, numif 2
+ usb.c: skipped 4 class/vendor specific interface descriptors
+ usb.c: new device strings: Mfr=1, Product=2, SerialNumber=3
+ usb.c: USB device number 2 default language ID 0x409
+ Manufacturer: 3Com Inc.
+ Product: 3Com U.S. Robotics Pro ISDN TA
+ SerialNumber: UFT53A49BVT7
+ acm.c: probing config 1
+ acm.c: probing config 2
+ ttyACM0: USB ACM device
+ acm.c: acm_control_msg: rq: 0x22 val: 0x0 len: 0x0 result: 0
+ acm.c: acm_control_msg: rq: 0x20 val: 0x0 len: 0x7 result: 7
+ usb.c: acm driver claimed interface c7b5f3e0
+ usb.c: acm driver claimed interface c7b5f3f8
+ usb.c: acm driver claimed interface c7691fa0
+
+If all this seems to be OK, fire up minicom and set it to talk to the ttyACM
+device and try typing 'at'. If it responds with 'OK', then everything is
+working.
diff --git a/Documentation/usb/authorization.rst b/Documentation/usb/authorization.rst
new file mode 100644
index 000000000..9e53909d0
--- /dev/null
+++ b/Documentation/usb/authorization.rst
@@ -0,0 +1,132 @@
+==============================================================
+Authorizing (or not) your USB devices to connect to the system
+==============================================================
+
+Copyright (C) 2007 Inaky Perez-Gonzalez <inaky@linux.intel.com> Intel Corporation
+
+This feature allows you to control if a USB device can be used (or
+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
+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.
+
+Usage
+=====
+
+Authorize a device to connect::
+
+ $ echo 1 > /sys/bus/usb/devices/DEVICE/authorized
+
+De-authorize a device::
+
+ $ echo 0 > /sys/bus/usb/devices/DEVICE/authorized
+
+Set new devices connected to hostX to be deauthorized by default (ie:
+lock down)::
+
+ $ echo 0 > /sys/bus/usb/devices/usbX/authorized_default
+
+Remove the lock down::
+
+ $ echo 1 > /sys/bus/usb/devices/usbX/authorized_default
+
+By default, Wired USB devices are authorized by default to
+connect. Wireless USB hosts deauthorize by default all new connected
+devices (this is so because we need to do an authentication phase
+before authorizing). Writing "2" to the authorized_default attribute
+causes kernel to only authorize by default devices connected to internal
+USB ports.
+
+
+Example system lockdown (lame)
+------------------------------
+
+Imagine you want to implement a lockdown so only devices of type XYZ
+can be connected (for example, it is a kiosk machine with a visible
+USB port)::
+
+ boot up
+ rc.local ->
+
+ for host in /sys/bus/usb/devices/usb*
+ do
+ echo 0 > $host/authorized_default
+ done
+
+Hookup an script to udev, for new USB devices::
+
+ if device_is_my_type $DEV
+ then
+ echo 1 > $device_path/authorized
+ done
+
+
+Now, device_is_my_type() is where the juice for a lockdown is. Just
+checking if the class, type and protocol match something is the worse
+security verification you can make (or the best, for someone willing
+to break it). If you need something secure, use crypto and Certificate
+Authentication or stuff like that. Something simple for an storage key
+could be::
+
+ function device_is_my_type()
+ {
+ echo 1 > authorized # temporarily authorize it
+ # FIXME: make sure none can mount it
+ mount DEVICENODE /mntpoint
+ sum=$(md5sum /mntpoint/.signature)
+ if [ $sum = $(cat /etc/lockdown/keysum) ]
+ then
+ echo "We are good, connected"
+ umount /mntpoint
+ # Other stuff so others can use it
+ else
+ echo 0 > authorized
+ fi
+ }
+
+
+Of course, this is lame, you'd want to do a real certificate
+verification stuff with PKI, so you don't depend on a shared secret,
+etc, but you get the idea. Anybody with access to a device gadget kit
+can fake descriptors and device info. Don't trust that. You are
+welcome.
+
+
+Interface authorization
+-----------------------
+
+There is a similar approach to allow or deny specific USB interfaces.
+That allows to block only a subset of an USB device.
+
+Authorize an interface::
+
+ $ echo 1 > /sys/bus/usb/devices/INTERFACE/authorized
+
+Deauthorize an interface::
+
+ $ echo 0 > /sys/bus/usb/devices/INTERFACE/authorized
+
+The default value for new interfaces
+on a particular USB bus can be changed, too.
+
+Allow interfaces per default::
+
+ $ echo 1 > /sys/bus/usb/devices/usbX/interface_authorized_default
+
+Deny interfaces per default::
+
+ $ echo 0 > /sys/bus/usb/devices/usbX/interface_authorized_default
+
+Per default the interface_authorized_default bit is 1.
+So all interfaces would authorized per default.
+
+Note:
+ If a deauthorized interface will be authorized so the driver probing must
+ be triggered manually by writing INTERFACE to /sys/bus/usb/drivers_probe
+
+For drivers that need multiple interfaces all needed interfaces should be
+authorized first. After that the drivers should be probed.
+This avoids side effects.
diff --git a/Documentation/usb/chipidea.rst b/Documentation/usb/chipidea.rst
new file mode 100644
index 000000000..68473abe2
--- /dev/null
+++ b/Documentation/usb/chipidea.rst
@@ -0,0 +1,133 @@
+==============================================
+ChipIdea Highspeed Dual Role Controller Driver
+==============================================
+
+1. How to test OTG FSM(HNP and SRP)
+-----------------------------------
+
+To show how to demo OTG HNP and SRP functions via sys input files
+with 2 Freescale i.MX6Q sabre SD boards.
+
+1.1 How to enable OTG FSM
+-------------------------
+
+1.1.1 Select CONFIG_USB_OTG_FSM in menuconfig, rebuild kernel
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Image and modules. If you want to check some internal
+variables for otg fsm, mount debugfs, there are 2 files
+which can show otg fsm variables and some controller registers value::
+
+ cat /sys/kernel/debug/ci_hdrc.0/otg
+ cat /sys/kernel/debug/ci_hdrc.0/registers
+
+1.1.2 Add below entries in your dts file for your controller node
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+::
+
+ otg-rev = <0x0200>;
+ adp-disable;
+
+1.2 Test operations
+-------------------
+
+1) Power up 2 Freescale i.MX6Q sabre SD boards with gadget class driver loaded
+ (e.g. g_mass_storage).
+
+2) Connect 2 boards with usb cable with one end is micro A plug, the other end
+ is micro B plug.
+
+ The A-device(with micro A plug inserted) should enumerate B-device.
+
+3) Role switch
+
+ On B-device::
+
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ B-device should take host role and enumerate A-device.
+
+4) A-device switch back to host.
+
+ On B-device::
+
+ echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ or, by introducing HNP polling, B-Host can know when A-peripheral wish
+ to be host role, so this role switch also can be trigged in A-peripheral
+ side by answering the polling from B-Host, this can be done on A-device::
+
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+ A-device should switch back to host and enumerate B-device.
+
+5) Remove B-device(unplug micro B plug) and insert again in 10 seconds,
+ A-device should enumerate B-device again.
+
+6) Remove B-device(unplug micro B plug) and insert again after 10 seconds,
+ A-device should NOT enumerate B-device.
+
+ if A-device wants to use bus:
+
+ On A-device::
+
+ echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+ if B-device wants to use bus:
+
+ On B-device::
+
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+7) A-device power down the bus.
+
+ On A-device::
+
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+
+ A-device should disconnect with B-device and power down the bus.
+
+8) B-device does data pulse for SRP.
+
+ On B-device::
+
+ echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+ A-device should resume usb bus and enumerate B-device.
+
+1.3 Reference document
+----------------------
+"On-The-Go and Embedded Host Supplement to the USB Revision 2.0 Specification
+July 27, 2012 Revision 2.0 version 1.1a"
+
+2. How to enable USB as system wakeup source
+--------------------------------------------
+Below is the example for how to enable USB as system wakeup source
+at imx6 platform.
+
+2.1 Enable core's wakeup::
+
+ echo enabled > /sys/bus/platform/devices/ci_hdrc.0/power/wakeup
+
+2.2 Enable glue layer's wakeup::
+
+ echo enabled > /sys/bus/platform/devices/2184000.usb/power/wakeup
+
+2.3 Enable PHY's wakeup (optional)::
+
+ echo enabled > /sys/bus/platform/devices/20c9000.usbphy/power/wakeup
+
+2.4 Enable roothub's wakeup::
+
+ echo enabled > /sys/bus/usb/devices/usb1/power/wakeup
+
+2.5 Enable related device's wakeup::
+
+ echo enabled > /sys/bus/usb/devices/1-1/power/wakeup
+
+If the system has only one usb port, and you want usb wakeup at this port, you
+can use below script to enable usb wakeup::
+
+ for i in $(find /sys -name wakeup | grep usb);do echo enabled > $i;done;
diff --git a/Documentation/usb/dwc3.rst b/Documentation/usb/dwc3.rst
new file mode 100644
index 000000000..f94a7ba16
--- /dev/null
+++ b/Documentation/usb/dwc3.rst
@@ -0,0 +1,53 @@
+===========
+DWC3 driver
+===========
+
+
+TODO
+~~~~
+
+Please pick something while reading :)
+
+- Convert interrupt handler to per-ep-thread-irq
+
+ As it turns out some DWC3-commands ~1ms to complete. Currently we spin
+ until the command completes which is bad.
+
+ Implementation idea:
+
+ - dwc core implements a demultiplexing irq chip for interrupts per
+ endpoint. The interrupt numbers are allocated during probe and belong
+ to the device. If MSI provides per-endpoint interrupt this dummy
+ interrupt chip can be replaced with "real" interrupts.
+ - interrupts are requested / allocated on usb_ep_enable() and removed on
+ usb_ep_disable(). Worst case are 32 interrupts, the lower limit is two
+ for ep0/1.
+ - dwc3_send_gadget_ep_cmd() will sleep in wait_for_completion_timeout()
+ until the command completes.
+ - the interrupt handler is split into the following pieces:
+
+ - primary handler of the device
+ goes through every event and calls generic_handle_irq() for event
+ it. On return from generic_handle_irq() in acknowledges the event
+ counter so interrupt goes away (eventually).
+
+ - threaded handler of the device
+ none
+
+ - primary handler of the EP-interrupt
+ reads the event and tries to process it. Everything that requires
+ sleeping is handed over to the Thread. The event is saved in an
+ per-endpoint data-structure.
+ We probably have to pay attention not to process events once we
+ handed something to thread so we don't process event X prio Y
+ where X > Y.
+
+ - threaded handler of the EP-interrupt
+ handles the remaining EP work which might sleep such as waiting
+ for command completion.
+
+ Latency:
+
+ There should be no increase in latency since the interrupt-thread has a
+ high priority and will be run before an average task in user land
+ (except the user changed priorities).
diff --git a/Documentation/usb/ehci.rst b/Documentation/usb/ehci.rst
new file mode 100644
index 000000000..31f650e7c
--- /dev/null
+++ b/Documentation/usb/ehci.rst
@@ -0,0 +1,230 @@
+===========
+EHCI driver
+===========
+
+27-Dec-2002
+
+The EHCI driver is used to talk to high speed USB 2.0 devices using
+USB 2.0-capable host controller hardware. The USB 2.0 standard is
+compatible with the USB 1.1 standard. It defines three transfer speeds:
+
+ - "High Speed" 480 Mbit/sec (60 MByte/sec)
+ - "Full Speed" 12 Mbit/sec (1.5 MByte/sec)
+ - "Low Speed" 1.5 Mbit/sec
+
+USB 1.1 only addressed full speed and low speed. High speed devices
+can be used on USB 1.1 systems, but they slow down to USB 1.1 speeds.
+
+USB 1.1 devices may also be used on USB 2.0 systems. When plugged
+into an EHCI controller, they are given to a USB 1.1 "companion"
+controller, which is a OHCI or UHCI controller as normally used with
+such devices. When USB 1.1 devices plug into USB 2.0 hubs, they
+interact with the EHCI controller through a "Transaction Translator"
+(TT) in the hub, which turns low or full speed transactions into
+high speed "split transactions" that don't waste transfer bandwidth.
+
+At this writing, this driver has been seen to work with implementations
+of EHCI from (in alphabetical order): Intel, NEC, Philips, and VIA.
+Other EHCI implementations are becoming available from other vendors;
+you should expect this driver to work with them too.
+
+While usb-storage devices have been available since mid-2001 (working
+quite speedily on the 2.4 version of this driver), hubs have only
+been available since late 2001, and other kinds of high speed devices
+appear to be on hold until more systems come with USB 2.0 built-in.
+Such new systems have been available since early 2002, and became much
+more typical in the second half of 2002.
+
+Note that USB 2.0 support involves more than just EHCI. It requires
+other changes to the Linux-USB core APIs, including the hub driver,
+but those changes haven't needed to really change the basic "usbcore"
+APIs exposed to USB device drivers.
+
+- David Brownell
+ <dbrownell@users.sourceforge.net>
+
+
+Functionality
+=============
+
+This driver is regularly tested on x86 hardware, and has also been
+used on PPC hardware so big/little endianness issues should be gone.
+It's believed to do all the right PCI magic so that I/O works even on
+systems with interesting DMA mapping issues.
+
+Transfer Types
+--------------
+
+At this writing the driver should comfortably handle all control, bulk,
+and interrupt transfers, including requests to USB 1.1 devices through
+transaction translators (TTs) in USB 2.0 hubs. But you may find bugs.
+
+High Speed Isochronous (ISO) transfer support is also functional, but
+at this writing no Linux drivers have been using that support.
+
+Full Speed Isochronous transfer support, through transaction translators,
+is not yet available. Note that split transaction support for ISO
+transfers can't share much code with the code for high speed ISO transfers,
+since EHCI represents these with a different data structure. So for now,
+most USB audio and video devices can't be connected to high speed buses.
+
+Driver Behavior
+---------------
+
+Transfers of all types can be queued. This means that control transfers
+from a driver on one interface (or through usbfs) won't interfere with
+ones from another driver, and that interrupt transfers can use periods
+of one frame without risking data loss due to interrupt processing costs.
+
+The EHCI root hub code hands off USB 1.1 devices to its companion
+controller. This driver doesn't need to know anything about those
+drivers; a OHCI or UHCI driver that works already doesn't need to change
+just because the EHCI driver is also present.
+
+There are some issues with power management; suspend/resume doesn't
+behave quite right at the moment.
+
+Also, some shortcuts have been taken with the scheduling periodic
+transactions (interrupt and isochronous transfers). These place some
+limits on the number of periodic transactions that can be scheduled,
+and prevent use of polling intervals of less than one frame.
+
+
+Use by
+======
+
+Assuming you have an EHCI controller (on a PCI card or motherboard)
+and have compiled this driver as a module, load this like::
+
+ # modprobe ehci-hcd
+
+and remove it by::
+
+ # rmmod ehci-hcd
+
+You should also have a driver for a "companion controller", such as
+"ohci-hcd" or "uhci-hcd". In case of any trouble with the EHCI driver,
+remove its module and then the driver for that companion controller will
+take over (at lower speed) all the devices that were previously handled
+by the EHCI driver.
+
+Module parameters (pass to "modprobe") include:
+
+ log2_irq_thresh (default 0):
+ Log2 of default interrupt delay, in microframes. The default
+ value is 0, indicating 1 microframe (125 usec). Maximum value
+ is 6, indicating 2^6 = 64 microframes. This controls how often
+ the EHCI controller can issue interrupts.
+
+If you're using this driver on a 2.5 kernel, and you've enabled USB
+debugging support, you'll see three files in the "sysfs" directory for
+any EHCI controller:
+
+ "async"
+ dumps the asynchronous schedule, used for control
+ and bulk transfers. Shows each active qh and the qtds
+ pending, usually one qtd per urb. (Look at it with
+ usb-storage doing disk I/O; watch the request queues!)
+ "periodic"
+ dumps the periodic schedule, used for interrupt
+ and isochronous transfers. Doesn't show qtds.
+ "registers"
+ show controller register state, and
+
+The contents of those files can help identify driver problems.
+
+
+Device drivers shouldn't care whether they're running over EHCI or not,
+but they may want to check for "usb_device->speed == USB_SPEED_HIGH".
+High speed devices can do things that full speed (or low speed) ones
+can't, such as "high bandwidth" periodic (interrupt or ISO) transfers.
+Also, some values in device descriptors (such as polling intervals for
+periodic transfers) use different encodings when operating at high speed.
+
+However, do make a point of testing device drivers through USB 2.0 hubs.
+Those hubs report some failures, such as disconnections, differently when
+transaction translators are in use; some drivers have been seen to behave
+badly when they see different faults than OHCI or UHCI report.
+
+
+Performance
+===========
+
+USB 2.0 throughput is gated by two main factors: how fast the host
+controller can process requests, and how fast devices can respond to
+them. The 480 Mbit/sec "raw transfer rate" is obeyed by all devices,
+but aggregate throughput is also affected by issues like delays between
+individual high speed packets, driver intelligence, and of course the
+overall system load. Latency is also a performance concern.
+
+Bulk transfers are most often used where throughput is an issue. It's
+good to keep in mind that bulk transfers are always in 512 byte packets,
+and at most 13 of those fit into one USB 2.0 microframe. Eight USB 2.0
+microframes fit in a USB 1.1 frame; a microframe is 1 msec/8 = 125 usec.
+
+So more than 50 MByte/sec is available for bulk transfers, when both
+hardware and device driver software allow it. Periodic transfer modes
+(isochronous and interrupt) allow the larger packet sizes which let you
+approach the quoted 480 MBit/sec transfer rate.
+
+Hardware Performance
+--------------------
+
+At this writing, individual USB 2.0 devices tend to max out at around
+20 MByte/sec transfer rates. This is of course subject to change;
+and some devices now go faster, while others go slower.
+
+The first NEC implementation of EHCI seems to have a hardware bottleneck
+at around 28 MByte/sec aggregate transfer rate. While this is clearly
+enough for a single device at 20 MByte/sec, putting three such devices
+onto one bus does not get you 60 MByte/sec. The issue appears to be
+that the controller hardware won't do concurrent USB and PCI access,
+so that it's only trying six (or maybe seven) USB transactions each
+microframe rather than thirteen. (Seems like a reasonable trade off
+for a product that beat all the others to market by over a year!)
+
+It's expected that newer implementations will better this, throwing
+more silicon real estate at the problem so that new motherboard chip
+sets will get closer to that 60 MByte/sec target. That includes an
+updated implementation from NEC, as well as other vendors' silicon.
+
+There's a minimum latency of one microframe (125 usec) for the host
+to receive interrupts from the EHCI controller indicating completion
+of requests. That latency is tunable; there's a module option. By
+default ehci-hcd driver uses the minimum latency, which means that if
+you issue a control or bulk request you can often expect to learn that
+it completed in less than 250 usec (depending on transfer size).
+
+Software Performance
+--------------------
+
+To get even 20 MByte/sec transfer rates, Linux-USB device drivers will
+need to keep the EHCI queue full. That means issuing large requests,
+or using bulk queuing if a series of small requests needs to be issued.
+When drivers don't do that, their performance results will show it.
+
+In typical situations, a usb_bulk_msg() loop writing out 4 KB chunks is
+going to waste more than half the USB 2.0 bandwidth. Delays between the
+I/O completion and the driver issuing the next request will take longer
+than the I/O. If that same loop used 16 KB chunks, it'd be better; a
+sequence of 128 KB chunks would waste a lot less.
+
+But rather than depending on such large I/O buffers to make synchronous
+I/O be efficient, it's better to just queue up several (bulk) requests
+to the HC, and wait for them all to complete (or be canceled on error).
+Such URB queuing should work with all the USB 1.1 HC drivers too.
+
+In the Linux 2.5 kernels, new usb_sg_*() api calls have been defined; they
+queue all the buffers from a scatterlist. They also use scatterlist DMA
+mapping (which might apply an IOMMU) and IRQ reduction, all of which will
+help make high speed transfers run as fast as they can.
+
+
+TBD:
+ Interrupt and ISO transfer performance issues. Those periodic
+ transfers are fully scheduled, so the main issue is likely to be how
+ to trigger "high bandwidth" modes.
+
+TBD:
+ More than standard 80% periodic bandwidth allocation is possible
+ through sysfs uframe_periodic_max parameter. Describe that.
diff --git a/Documentation/usb/functionfs.rst b/Documentation/usb/functionfs.rst
new file mode 100644
index 000000000..7fdc6d840
--- /dev/null
+++ b/Documentation/usb/functionfs.rst
@@ -0,0 +1,68 @@
+====================
+How FunctionFS works
+====================
+
+From kernel point of view it is just a composite function with some
+unique behaviour. It may be added to an USB configuration only after
+the user space driver has registered by writing descriptors and
+strings (the user space program has to provide the same information
+that kernel level composite functions provide when they are added to
+the configuration).
+
+This in particular means that the composite initialisation functions
+may not be in init section (ie. may not use the __init tag).
+
+From user space point of view it is a file system which when
+mounted provides an "ep0" file. User space driver need to
+write descriptors and strings to that file. It does not need
+to worry about endpoints, interfaces or strings numbers but
+simply provide descriptors such as if the function was the
+only one (endpoints and strings numbers starting from one and
+interface numbers starting from zero). The FunctionFS changes
+them as needed also handling situation when numbers differ in
+different configurations.
+
+When descriptors and strings are written "ep#" files appear
+(one for each declared endpoint) which handle communication on
+a single endpoint. Again, FunctionFS takes care of the real
+numbers and changing of the configuration (which means that
+"ep1" file may be really mapped to (say) endpoint 3 (and when
+configuration changes to (say) endpoint 2)). "ep0" is used
+for receiving events and handling setup requests.
+
+When all files are closed the function disables itself.
+
+What I also want to mention is that the FunctionFS is designed in such
+a way that it is possible to mount it several times so in the end
+a gadget could use several FunctionFS functions. The idea is that
+each FunctionFS instance is identified by the device name used
+when mounting.
+
+One can imagine a gadget that has an Ethernet, MTP and HID interfaces
+where the last two are implemented via FunctionFS. On user space
+level it would look like this::
+
+ $ insmod g_ffs.ko idVendor=<ID> iSerialNumber=<string> functions=mtp,hid
+ $ mkdir /dev/ffs-mtp && mount -t functionfs mtp /dev/ffs-mtp
+ $ ( cd /dev/ffs-mtp && mtp-daemon ) &
+ $ mkdir /dev/ffs-hid && mount -t functionfs hid /dev/ffs-hid
+ $ ( cd /dev/ffs-hid && hid-daemon ) &
+
+On kernel level the gadget checks ffs_data->dev_name to identify
+whether it's FunctionFS designed for MTP ("mtp") or HID ("hid").
+
+If no "functions" module parameters is supplied, the driver accepts
+just one function with any name.
+
+When "functions" module parameter is supplied, only functions
+with listed names are accepted. In particular, if the "functions"
+parameter's value is just a one-element list, then the behaviour
+is similar to when there is no "functions" at all; however,
+only a function with the specified name is accepted.
+
+The gadget is registered only after all the declared function
+filesystems have been mounted and USB descriptors of all functions
+have been written to their ep0's.
+
+Conversely, the gadget is unregistered after the first USB function
+closes its endpoints.
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
new file mode 100644
index 000000000..2eeb3e929
--- /dev/null
+++ b/Documentation/usb/gadget-testing.rst
@@ -0,0 +1,934 @@
+==============
+Gadget Testing
+==============
+
+This file summarizes information on basic testing of USB functions
+provided by gadgets.
+
+.. contents
+
+ 1. ACM function
+ 2. ECM function
+ 3. ECM subset function
+ 4. EEM function
+ 5. FFS function
+ 6. HID function
+ 7. LOOPBACK function
+ 8. MASS STORAGE function
+ 9. MIDI function
+ 10. NCM function
+ 11. OBEX function
+ 12. PHONET function
+ 13. RNDIS function
+ 14. SERIAL function
+ 15. SOURCESINK function
+ 16. UAC1 function (legacy implementation)
+ 17. UAC2 function
+ 18. UVC function
+ 19. PRINTER function
+ 20. UAC1 function (new API)
+
+
+1. ACM function
+===============
+
+The function is provided by usb_f_acm.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "acm".
+The ACM function provides just one attribute in its function directory:
+
+ port_num
+
+The attribute is read-only.
+
+There can be at most 4 ACM/generic serial/OBEX ports in the system.
+
+
+Testing the ACM function
+------------------------
+
+On the host::
+
+ cat > /dev/ttyACM<X>
+
+On the device::
+
+ cat /dev/ttyGS<Y>
+
+then the other way round
+
+On the device::
+
+ cat > /dev/ttyGS<Y>
+
+On the host::
+
+ cat /dev/ttyACM<X>
+
+2. ECM function
+===============
+
+The function is provided by usb_f_ecm.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "ecm".
+The ECM function provides these attributes in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ qmult queue length multiplier for high and super speed
+ host_addr MAC address of host's end of this
+ Ethernet over USB link
+ dev_addr MAC address of device's end of this
+ Ethernet over USB link
+ =============== ==================================================
+
+and after creating the functions/ecm.<instance name> they contain default
+values: qmult is 5, dev_addr and host_addr are randomly selected.
+Except for ifname they can be written to until the function is linked to a
+configuration. The ifname is read-only and contains the name of the interface
+which was assigned by the net core, e. g. usb0.
+
+Testing the ECM function
+------------------------
+
+Configure IP addresses of the device and the host. Then:
+
+On the device::
+
+ ping <host's IP>
+
+On the host::
+
+ ping <device's IP>
+
+3. ECM subset function
+======================
+
+The function is provided by usb_f_ecm_subset.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "geth".
+The ECM subset function provides these attributes in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ qmult queue length multiplier for high and super speed
+ host_addr MAC address of host's end of this
+ Ethernet over USB link
+ dev_addr MAC address of device's end of this
+ Ethernet over USB link
+ =============== ==================================================
+
+and after creating the functions/ecm.<instance name> they contain default
+values: qmult is 5, dev_addr and host_addr are randomly selected.
+Except for ifname they can be written to until the function is linked to a
+configuration. The ifname is read-only and contains the name of the interface
+which was assigned by the net core, e. g. usb0.
+
+Testing the ECM subset function
+-------------------------------
+
+Configure IP addresses of the device and the host. Then:
+
+On the device::
+
+ ping <host's IP>
+
+On the host::
+
+ ping <device's IP>
+
+4. EEM function
+===============
+
+The function is provided by usb_f_eem.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "eem".
+The EEM function provides these attributes in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ qmult queue length multiplier for high and super speed
+ host_addr MAC address of host's end of this
+ Ethernet over USB link
+ dev_addr MAC address of device's end of this
+ Ethernet over USB link
+ =============== ==================================================
+
+and after creating the functions/eem.<instance name> they contain default
+values: qmult is 5, dev_addr and host_addr are randomly selected.
+Except for ifname they can be written to until the function is linked to a
+configuration. The ifname is read-only and contains the name of the interface
+which was assigned by the net core, e. g. usb0.
+
+Testing the EEM function
+------------------------
+
+Configure IP addresses of the device and the host. Then:
+
+On the device::
+
+ ping <host's IP>
+
+On the host::
+
+ ping <device's IP>
+
+5. FFS function
+===============
+
+The function is provided by usb_f_fs.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "ffs".
+The function directory is intentionally empty and not modifiable.
+
+After creating the directory there is a new instance (a "device") of FunctionFS
+available in the system. Once a "device" is available, the user should follow
+the standard procedure for using FunctionFS (mount it, run the userspace
+process which implements the function proper). The gadget should be enabled
+by writing a suitable string to usb_gadget/<gadget>/UDC.
+
+Testing the FFS function
+------------------------
+
+On the device: start the function's userspace daemon, enable the gadget
+
+On the host: use the USB function provided by the device
+
+6. HID function
+===============
+
+The function is provided by usb_f_hid.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "hid".
+The HID function provides these attributes in its function directory:
+
+ =============== ===========================================
+ protocol HID protocol to use
+ report_desc data to be used in HID reports, except data
+ passed with /dev/hidg<X>
+ report_length HID report length
+ subclass HID subclass to use
+ =============== ===========================================
+
+For a keyboard the protocol and the subclass are 1, the report_length is 8,
+while the report_desc is::
+
+ $ hd my_report_desc
+ 00000000 05 01 09 06 a1 01 05 07 19 e0 29 e7 15 00 25 01 |..........)...%.|
+ 00000010 75 01 95 08 81 02 95 01 75 08 81 03 95 05 75 01 |u.......u.....u.|
+ 00000020 05 08 19 01 29 05 91 02 95 01 75 03 91 03 95 06 |....).....u.....|
+ 00000030 75 08 15 00 25 65 05 07 19 00 29 65 81 00 c0 |u...%e....)e...|
+ 0000003f
+
+Such a sequence of bytes can be stored to the attribute with echo::
+
+ $ echo -ne \\x05\\x01\\x09\\x06\\xa1.....
+
+Testing the HID function
+------------------------
+
+Device:
+
+- create the gadget
+- connect the gadget to a host, preferably not the one used
+ to control the gadget
+- run a program which writes to /dev/hidg<N>, e.g.
+ a userspace program found in Documentation/usb/gadget_hid.rst::
+
+ $ ./hid_gadget_test /dev/hidg0 keyboard
+
+Host:
+
+- observe the keystrokes from the gadget
+
+7. LOOPBACK function
+====================
+
+The function is provided by usb_f_ss_lb.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "Loopback".
+The LOOPBACK function provides these attributes in its function directory:
+
+ =============== =======================
+ qlen depth of loopback queue
+ bulk_buflen buffer length
+ =============== =======================
+
+Testing the LOOPBACK function
+-----------------------------
+
+device: run the gadget
+
+host: test-usb (tools/usb/testusb.c)
+
+8. MASS STORAGE function
+========================
+
+The function is provided by usb_f_mass_storage.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "mass_storage".
+The MASS STORAGE function provides these attributes in its directory:
+files:
+
+ =============== ==============================================
+ stall Set to permit function to halt bulk endpoints.
+ Disabled on some USB devices known not to work
+ correctly. You should set it to true.
+ num_buffers Number of pipeline buffers. Valid numbers
+ are 2..4. Available only if
+ CONFIG_USB_GADGET_DEBUG_FILES is set.
+ =============== ==============================================
+
+and a default lun.0 directory corresponding to SCSI LUN #0.
+
+A new lun can be added with mkdir::
+
+ $ mkdir functions/mass_storage.0/partition.5
+
+Lun numbering does not have to be continuous, except for lun #0 which is
+created by default. A maximum of 8 luns can be specified and they all must be
+named following the <name>.<number> scheme. The numbers can be 0..8.
+Probably a good convention is to name the luns "lun.<number>",
+although it is not mandatory.
+
+In each lun directory there are the following attribute files:
+
+ =============== ==============================================
+ file The path to the backing file for the LUN.
+ Required if LUN is not marked as removable.
+ ro Flag specifying access to the LUN shall be
+ read-only. This is implied if CD-ROM emulation
+ is enabled as well as when it was impossible
+ to open "filename" in R/W mode.
+ removable Flag specifying that LUN shall be indicated as
+ being removable.
+ cdrom Flag specifying that LUN shall be reported as
+ being a CD-ROM.
+ nofua Flag specifying that FUA flag
+ in SCSI WRITE(10,12)
+ =============== ==============================================
+
+Testing the MASS STORAGE function
+---------------------------------
+
+device: connect the gadget, enable it
+host: dmesg, see the USB drives appear (if system configured to automatically
+mount)
+
+9. MIDI function
+================
+
+The function is provided by usb_f_midi.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "midi".
+The MIDI function provides these attributes in its function directory:
+
+ =============== ====================================
+ buflen MIDI buffer length
+ id ID string for the USB MIDI adapter
+ in_ports number of MIDI input ports
+ index index value for the USB MIDI adapter
+ out_ports number of MIDI output ports
+ qlen USB read request queue length
+ =============== ====================================
+
+Testing the MIDI function
+-------------------------
+
+There are two cases: playing a mid from the gadget to
+the host and playing a mid from the host to the gadget.
+
+1) Playing a mid from the gadget to the host:
+
+host::
+
+ $ arecordmidi -l
+ Port Client name Port name
+ 14:0 Midi Through Midi Through Port-0
+ 24:0 MIDI Gadget MIDI Gadget MIDI 1
+ $ arecordmidi -p 24:0 from_gadget.mid
+
+gadget::
+
+ $ aplaymidi -l
+ Port Client name Port name
+ 20:0 f_midi f_midi
+
+ $ aplaymidi -p 20:0 to_host.mid
+
+2) Playing a mid from the host to the gadget
+
+gadget::
+
+ $ arecordmidi -l
+ Port Client name Port name
+ 20:0 f_midi f_midi
+
+ $ arecordmidi -p 20:0 from_host.mid
+
+host::
+
+ $ aplaymidi -l
+ Port Client name Port name
+ 14:0 Midi Through Midi Through Port-0
+ 24:0 MIDI Gadget MIDI Gadget MIDI 1
+
+ $ aplaymidi -p24:0 to_gadget.mid
+
+The from_gadget.mid should sound identical to the to_host.mid.
+
+The from_host.id should sound identical to the to_gadget.mid.
+
+MIDI files can be played to speakers/headphones with e.g. timidity installed::
+
+ $ aplaymidi -l
+ Port Client name Port name
+ 14:0 Midi Through Midi Through Port-0
+ 24:0 MIDI Gadget MIDI Gadget MIDI 1
+ 128:0 TiMidity TiMidity port 0
+ 128:1 TiMidity TiMidity port 1
+ 128:2 TiMidity TiMidity port 2
+ 128:3 TiMidity TiMidity port 3
+
+ $ aplaymidi -p 128:0 file.mid
+
+MIDI ports can be logically connected using the aconnect utility, e.g.::
+
+ $ aconnect 24:0 128:0 # try it on the host
+
+After the gadget's MIDI port is connected to timidity's MIDI port,
+whatever is played at the gadget side with aplaymidi -l is audible
+in host's speakers/headphones.
+
+10. NCM function
+================
+
+The function is provided by usb_f_ncm.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "ncm".
+The NCM function provides these attributes in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ qmult queue length multiplier for high and super speed
+ host_addr MAC address of host's end of this
+ Ethernet over USB link
+ dev_addr MAC address of device's end of this
+ Ethernet over USB link
+ =============== ==================================================
+
+and after creating the functions/ncm.<instance name> they contain default
+values: qmult is 5, dev_addr and host_addr are randomly selected.
+Except for ifname they can be written to until the function is linked to a
+configuration. The ifname is read-only and contains the name of the interface
+which was assigned by the net core, e. g. usb0.
+
+Testing the NCM function
+------------------------
+
+Configure IP addresses of the device and the host. Then:
+
+On the device::
+
+ ping <host's IP>
+
+On the host::
+
+ ping <device's IP>
+
+11. OBEX function
+=================
+
+The function is provided by usb_f_obex.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "obex".
+The OBEX function provides just one attribute in its function directory:
+
+ port_num
+
+The attribute is read-only.
+
+There can be at most 4 ACM/generic serial/OBEX ports in the system.
+
+Testing the OBEX function
+-------------------------
+
+On device::
+
+ seriald -f /dev/ttyGS<Y> -s 1024
+
+On host::
+
+ serialc -v <vendorID> -p <productID> -i<interface#> -a1 -s1024 \
+ -t<out endpoint addr> -r<in endpoint addr>
+
+where seriald and serialc are Felipe's utilities found here:
+
+ https://github.com/felipebalbi/usb-tools.git master
+
+12. PHONET function
+===================
+
+The function is provided by usb_f_phonet.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "phonet".
+The PHONET function provides just one attribute in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ =============== ==================================================
+
+Testing the PHONET function
+---------------------------
+
+It is not possible to test the SOCK_STREAM protocol without a specific piece
+of hardware, so only SOCK_DGRAM has been tested. For the latter to work,
+in the past I had to apply the patch mentioned here:
+
+http://www.spinics.net/lists/linux-usb/msg85689.html
+
+These tools are required:
+
+git://git.gitorious.org/meego-cellular/phonet-utils.git
+
+On the host::
+
+ $ ./phonet -a 0x10 -i usbpn0
+ $ ./pnroute add 0x6c usbpn0
+ $./pnroute add 0x10 usbpn0
+ $ ifconfig usbpn0 up
+
+On the device::
+
+ $ ./phonet -a 0x6c -i upnlink0
+ $ ./pnroute add 0x10 upnlink0
+ $ ifconfig upnlink0 up
+
+Then a test program can be used::
+
+ http://www.spinics.net/lists/linux-usb/msg85690.html
+
+On the device::
+
+ $ ./pnxmit -a 0x6c -r
+
+On the host::
+
+ $ ./pnxmit -a 0x10 -s 0x6c
+
+As a result some data should be sent from host to device.
+Then the other way round:
+
+On the host::
+
+ $ ./pnxmit -a 0x10 -r
+
+On the device::
+
+ $ ./pnxmit -a 0x6c -s 0x10
+
+13. RNDIS function
+==================
+
+The function is provided by usb_f_rndis.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "rndis".
+The RNDIS function provides these attributes in its function directory:
+
+ =============== ==================================================
+ ifname network device interface name associated with this
+ function instance
+ qmult queue length multiplier for high and super speed
+ host_addr MAC address of host's end of this
+ Ethernet over USB link
+ dev_addr MAC address of device's end of this
+ Ethernet over USB link
+ =============== ==================================================
+
+and after creating the functions/rndis.<instance name> they contain default
+values: qmult is 5, dev_addr and host_addr are randomly selected.
+Except for ifname they can be written to until the function is linked to a
+configuration. The ifname is read-only and contains the name of the interface
+which was assigned by the net core, e. g. usb0.
+
+Testing the RNDIS function
+--------------------------
+
+Configure IP addresses of the device and the host. Then:
+
+On the device::
+
+ ping <host's IP>
+
+On the host::
+
+ ping <device's IP>
+
+14. SERIAL function
+===================
+
+The function is provided by usb_f_gser.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "gser".
+The SERIAL function provides just one attribute in its function directory:
+
+ port_num
+
+The attribute is read-only.
+
+There can be at most 4 ACM/generic serial/OBEX ports in the system.
+
+Testing the SERIAL function
+---------------------------
+
+On host::
+
+ insmod usbserial
+ echo VID PID >/sys/bus/usb-serial/drivers/generic/new_id
+
+On host::
+
+ cat > /dev/ttyUSB<X>
+
+On target::
+
+ cat /dev/ttyGS<Y>
+
+then the other way round
+
+On target::
+
+ cat > /dev/ttyGS<Y>
+
+On host::
+
+ cat /dev/ttyUSB<X>
+
+15. SOURCESINK function
+=======================
+
+The function is provided by usb_f_ss_lb.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "SourceSink".
+The SOURCESINK function provides these attributes in its function directory:
+
+ =============== ==================================
+ pattern 0 (all zeros), 1 (mod63), 2 (none)
+ isoc_interval 1..16
+ isoc_maxpacket 0 - 1023 (fs), 0 - 1024 (hs/ss)
+ isoc_mult 0..2 (hs/ss only)
+ isoc_maxburst 0..15 (ss only)
+ bulk_buflen buffer length
+ bulk_qlen depth of queue for bulk
+ iso_qlen depth of queue for iso
+ =============== ==================================
+
+Testing the SOURCESINK function
+-------------------------------
+
+device: run the gadget
+
+host: test-usb (tools/usb/testusb.c)
+
+
+16. UAC1 function (legacy implementation)
+=========================================
+
+The function is provided by usb_f_uac1_legacy.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory
+is "uac1_legacy".
+The uac1 function provides these attributes in its function directory:
+
+ =============== ====================================
+ audio_buf_size audio buffer size
+ fn_cap capture pcm device file name
+ fn_cntl control device file name
+ fn_play playback pcm device file name
+ req_buf_size ISO OUT endpoint request buffer size
+ req_count ISO OUT endpoint request count
+ =============== ====================================
+
+The attributes have sane default values.
+
+Testing the UAC1 function
+-------------------------
+
+device: run the gadget
+
+host::
+
+ aplay -l # should list our USB Audio Gadget
+
+17. UAC2 function
+=================
+
+The function is provided by usb_f_uac2.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "uac2".
+The uac2 function provides these attributes in its function directory:
+
+ =============== ====================================================
+ c_chmask capture channel mask
+ c_srate capture sampling rate
+ c_ssize capture sample size (bytes)
+ p_chmask playback channel mask
+ p_srate playback sampling rate
+ p_ssize playback sample size (bytes)
+ req_number the number of pre-allocated request for both capture
+ and playback
+ =============== ====================================================
+
+The attributes have sane default values.
+
+Testing the UAC2 function
+-------------------------
+
+device: run the gadget
+host: aplay -l # should list our USB Audio Gadget
+
+This function does not require real hardware support, it just
+sends a stream of audio data to/from the host. In order to
+actually hear something at the device side, a command similar
+to this must be used at the device side::
+
+ $ arecord -f dat -t wav -D hw:2,0 | aplay -D hw:0,0 &
+
+e.g.::
+
+ $ arecord -f dat -t wav -D hw:CARD=UAC2Gadget,DEV=0 | \
+ aplay -D default:CARD=OdroidU3
+
+18. UVC function
+================
+
+The function is provided by usb_f_uvc.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "uvc".
+The uvc function provides these attributes in its function directory:
+
+ =================== ================================================
+ streaming_interval interval for polling endpoint for data transfers
+ streaming_maxburst bMaxBurst for super speed companion descriptor
+ streaming_maxpacket maximum packet size this endpoint is capable of
+ sending or receiving when this configuration is
+ selected
+ =================== ================================================
+
+There are also "control" and "streaming" subdirectories, each of which contain
+a number of their subdirectories. There are some sane defaults provided, but
+the user must provide the following:
+
+ ================== ====================================================
+ control header create in control/header, link from control/class/fs
+ and/or control/class/ss
+ streaming header create in streaming/header, link from
+ streaming/class/fs and/or streaming/class/hs and/or
+ streaming/class/ss
+ format description create in streaming/mjpeg and/or
+ streaming/uncompressed
+ frame description create in streaming/mjpeg/<format> and/or in
+ streaming/uncompressed/<format>
+ ================== ====================================================
+
+Each frame description contains frame interval specification, and each
+such specification consists of a number of lines with an inverval value
+in each line. The rules stated above are best illustrated with an example::
+
+ # mkdir functions/uvc.usb0/control/header/h
+ # cd functions/uvc.usb0/control/
+ # ln -s header/h class/fs
+ # ln -s header/h class/ss
+ # mkdir -p functions/uvc.usb0/streaming/uncompressed/u/360p
+ # cat <<EOF > functions/uvc.usb0/streaming/uncompressed/u/360p/dwFrameInterval
+ 666666
+ 1000000
+ 5000000
+ EOF
+ # cd $GADGET_CONFIGFS_ROOT
+ # mkdir functions/uvc.usb0/streaming/header/h
+ # cd functions/uvc.usb0/streaming/header/h
+ # ln -s ../../uncompressed/u
+ # cd ../../class/fs
+ # ln -s ../../header/h
+ # cd ../../class/hs
+ # ln -s ../../header/h
+ # cd ../../class/ss
+ # ln -s ../../header/h
+
+
+Testing the UVC function
+------------------------
+
+device: run the gadget, modprobe vivid::
+
+ # uvc-gadget -u /dev/video<uvc video node #> -v /dev/video<vivid video node #>
+
+where uvc-gadget is this program:
+ http://git.ideasonboard.org/uvc-gadget.git
+
+with these patches:
+
+ http://www.spinics.net/lists/linux-usb/msg99220.html
+
+host::
+
+ luvcview -f yuv
+
+19. PRINTER function
+====================
+
+The function is provided by usb_f_printer.ko module.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "printer".
+The printer function provides these attributes in its function directory:
+
+ ========== ===========================================
+ pnp_string Data to be passed to the host in pnp string
+ q_len Number of requests per endpoint
+ ========== ===========================================
+
+Testing the PRINTER function
+----------------------------
+
+The most basic testing:
+
+device: run the gadget::
+
+ # ls -l /devices/virtual/usb_printer_gadget/
+
+should show g_printer<number>.
+
+If udev is active, then /dev/g_printer<number> should appear automatically.
+
+host:
+
+If udev is active, then e.g. /dev/usb/lp0 should appear.
+
+host->device transmission:
+
+device::
+
+ # cat /dev/g_printer<number>
+
+host::
+
+ # cat > /dev/usb/lp0
+
+device->host transmission::
+
+ # cat > /dev/g_printer<number>
+
+host::
+
+ # cat /dev/usb/lp0
+
+More advanced testing can be done with the prn_example
+described in Documentation/usb/gadget_printer.rst.
+
+
+20. UAC1 function (virtual ALSA card, using u_audio API)
+========================================================
+
+The function is provided by usb_f_uac1.ko module.
+It will create a virtual ALSA card and the audio streams are simply
+sinked to and sourced from it.
+
+Function-specific configfs interface
+------------------------------------
+
+The function name to use when creating the function directory is "uac1".
+The uac1 function provides these attributes in its function directory:
+
+ ========== ====================================================
+ c_chmask capture channel mask
+ c_srate capture sampling rate
+ c_ssize capture sample size (bytes)
+ p_chmask playback channel mask
+ p_srate playback sampling rate
+ p_ssize playback sample size (bytes)
+ req_number the number of pre-allocated request for both capture
+ and playback
+ ========== ====================================================
+
+The attributes have sane default values.
+
+Testing the UAC1 function
+-------------------------
+
+device: run the gadget
+host: aplay -l # should list our USB Audio Gadget
+
+This function does not require real hardware support, it just
+sends a stream of audio data to/from the host. In order to
+actually hear something at the device side, a command similar
+to this must be used at the device side::
+
+ $ arecord -f dat -t wav -D hw:2,0 | aplay -D hw:0,0 &
+
+e.g.::
+
+ $ arecord -f dat -t wav -D hw:CARD=UAC1Gadget,DEV=0 | \
+ aplay -D default:CARD=OdroidU3
diff --git a/Documentation/usb/gadget_configfs.rst b/Documentation/usb/gadget_configfs.rst
new file mode 100644
index 000000000..158e48dab
--- /dev/null
+++ b/Documentation/usb/gadget_configfs.rst
@@ -0,0 +1,390 @@
+============================================
+Linux USB gadget configured through configfs
+============================================
+
+
+25th April 2013
+
+
+
+
+Overview
+========
+
+A USB Linux Gadget is a device which has a UDC (USB Device Controller) and can
+be connected to a USB Host to extend it with additional functions like a serial
+port or a mass storage capability.
+
+A gadget is seen by its host as a set of configurations, each of which contains
+a number of interfaces which, from the gadget's perspective, are known as
+functions, each function representing e.g. a serial connection or a SCSI disk.
+
+Linux provides a number of functions for gadgets to use.
+
+Creating a gadget means deciding what configurations there will be
+and which functions each configuration will provide.
+
+Configfs (please see `Documentation/filesystems/configfs.rst`) lends itself nicely
+for the purpose of telling the kernel about the above mentioned decision.
+This document is about how to do it.
+
+It also describes how configfs integration into gadget is designed.
+
+
+
+
+Requirements
+============
+
+In order for this to work configfs must be available, so CONFIGFS_FS must be
+'y' or 'm' in .config. As of this writing USB_LIBCOMPOSITE selects CONFIGFS_FS.
+
+
+
+
+Usage
+=====
+
+(The original post describing the first function
+made available through configfs can be seen here:
+http://www.spinics.net/lists/linux-usb/msg76388.html)
+
+::
+
+ $ modprobe libcomposite
+ $ mount none $CONFIGFS_HOME -t configfs
+
+where CONFIGFS_HOME is the mount point for configfs
+
+1. Creating the gadgets
+-----------------------
+
+For each gadget to be created its corresponding directory must be created::
+
+ $ mkdir $CONFIGFS_HOME/usb_gadget/<gadget name>
+
+e.g.::
+
+ $ mkdir $CONFIGFS_HOME/usb_gadget/g1
+
+ ...
+ ...
+ ...
+
+ $ cd $CONFIGFS_HOME/usb_gadget/g1
+
+Each gadget needs to have its vendor id <VID> and product id <PID> specified::
+
+ $ echo <VID> > idVendor
+ $ echo <PID> > idProduct
+
+A gadget also needs its serial number, manufacturer and product strings.
+In order to have a place to store them, a strings subdirectory must be created
+for each language, e.g.::
+
+ $ mkdir strings/0x409
+
+Then the strings can be specified::
+
+ $ echo <serial number> > strings/0x409/serialnumber
+ $ echo <manufacturer> > strings/0x409/manufacturer
+ $ echo <product> > strings/0x409/product
+
+2. Creating the configurations
+------------------------------
+
+Each gadget will consist of a number of configurations, their corresponding
+directories must be created:
+
+$ mkdir configs/<name>.<number>
+
+where <name> can be any string which is legal in a filesystem and the
+<number> is the configuration's number, e.g.::
+
+ $ mkdir configs/c.1
+
+ ...
+ ...
+ ...
+
+Each configuration also needs its strings, so a subdirectory must be created
+for each language, e.g.::
+
+ $ mkdir configs/c.1/strings/0x409
+
+Then the configuration string can be specified::
+
+ $ echo <configuration> > configs/c.1/strings/0x409/configuration
+
+Some attributes can also be set for a configuration, e.g.::
+
+ $ echo 120 > configs/c.1/MaxPower
+
+3. Creating the functions
+-------------------------
+
+The gadget will provide some functions, for each function its corresponding
+directory must be created::
+
+ $ mkdir functions/<name>.<instance name>
+
+where <name> corresponds to one of allowed function names and instance name
+is an arbitrary string allowed in a filesystem, e.g.::
+
+ $ mkdir functions/ncm.usb0 # usb_f_ncm.ko gets loaded with request_module()
+
+ ...
+ ...
+ ...
+
+Each function provides its specific set of attributes, with either read-only
+or read-write access. Where applicable they need to be written to as
+appropriate.
+Please refer to Documentation/ABI/*/configfs-usb-gadget* for more information.
+
+4. Associating the functions with their configurations
+------------------------------------------------------
+
+At this moment a number of gadgets is created, each of which has a number of
+configurations specified and a number of functions available. What remains
+is specifying which function is available in which configuration (the same
+function can be used in multiple configurations). This is achieved with
+creating symbolic links::
+
+ $ ln -s functions/<name>.<instance name> configs/<name>.<number>
+
+e.g.::
+
+ $ ln -s functions/ncm.usb0 configs/c.1
+
+ ...
+ ...
+ ...
+
+5. Enabling the gadget
+----------------------
+
+All the above steps serve the purpose of composing the gadget of
+configurations and functions.
+
+An example directory structure might look like this::
+
+ .
+ ./strings
+ ./strings/0x409
+ ./strings/0x409/serialnumber
+ ./strings/0x409/product
+ ./strings/0x409/manufacturer
+ ./configs
+ ./configs/c.1
+ ./configs/c.1/ncm.usb0 -> ../../../../usb_gadget/g1/functions/ncm.usb0
+ ./configs/c.1/strings
+ ./configs/c.1/strings/0x409
+ ./configs/c.1/strings/0x409/configuration
+ ./configs/c.1/bmAttributes
+ ./configs/c.1/MaxPower
+ ./functions
+ ./functions/ncm.usb0
+ ./functions/ncm.usb0/ifname
+ ./functions/ncm.usb0/qmult
+ ./functions/ncm.usb0/host_addr
+ ./functions/ncm.usb0/dev_addr
+ ./UDC
+ ./bcdUSB
+ ./bcdDevice
+ ./idProduct
+ ./idVendor
+ ./bMaxPacketSize0
+ ./bDeviceProtocol
+ ./bDeviceSubClass
+ ./bDeviceClass
+
+
+Such a gadget must be finally enabled so that the USB host can enumerate it.
+
+In order to enable the gadget it must be bound to a UDC (USB Device
+Controller)::
+
+ $ echo <udc name> > UDC
+
+where <udc name> is one of those found in /sys/class/udc/*
+e.g.::
+
+ $ echo s3c-hsotg > UDC
+
+
+6. Disabling the gadget
+-----------------------
+
+::
+
+ $ echo "" > UDC
+
+7. Cleaning up
+--------------
+
+Remove functions from configurations::
+
+ $ rm configs/<config name>.<number>/<function>
+
+where <config name>.<number> specify the configuration and <function> is
+a symlink to a function being removed from the configuration, e.g.::
+
+ $ rm configs/c.1/ncm.usb0
+
+ ...
+ ...
+ ...
+
+Remove strings directories in configurations:
+
+ $ rmdir configs/<config name>.<number>/strings/<lang>
+
+e.g.::
+
+ $ rmdir configs/c.1/strings/0x409
+
+ ...
+ ...
+ ...
+
+and remove the configurations::
+
+ $ rmdir configs/<config name>.<number>
+
+e.g.::
+
+ rmdir configs/c.1
+
+ ...
+ ...
+ ...
+
+Remove functions (function modules are not unloaded, though):
+
+ $ rmdir functions/<name>.<instance name>
+
+e.g.::
+
+ $ rmdir functions/ncm.usb0
+
+ ...
+ ...
+ ...
+
+Remove strings directories in the gadget::
+
+ $ rmdir strings/<lang>
+
+e.g.::
+
+ $ rmdir strings/0x409
+
+and finally remove the gadget::
+
+ $ cd ..
+ $ rmdir <gadget name>
+
+e.g.::
+
+ $ rmdir g1
+
+
+
+
+Implementation design
+=====================
+
+Below the idea of how configfs works is presented.
+In configfs there are items and groups, both represented as directories.
+The difference between an item and a group is that a group can contain
+other groups. In the picture below only an item is shown.
+Both items and groups can have attributes, which are represented as files.
+The user can create and remove directories, but cannot remove files,
+which can be read-only or read-write, depending on what they represent.
+
+The filesystem part of configfs operates on config_items/groups and
+configfs_attributes which are generic and of the same type for all
+configured elements. However, they are embedded in usage-specific
+larger structures. In the picture below there is a "cs" which contains
+a config_item and an "sa" which contains a configfs_attribute.
+
+The filesystem view would be like this::
+
+ ./
+ ./cs (directory)
+ |
+ +--sa (file)
+ |
+ .
+ .
+ .
+
+Whenever a user reads/writes the "sa" file, a function is called
+which accepts a struct config_item and a struct configfs_attribute.
+In the said function the "cs" and "sa" are retrieved using the well
+known container_of technique and an appropriate sa's function (show or
+store) is called and passed the "cs" and a character buffer. The "show"
+is for displaying the file's contents (copy data from the cs to the
+buffer), while the "store" is for modifying the file's contents (copy data
+from the buffer to the cs), but it is up to the implementer of the
+two functions to decide what they actually do.
+
+::
+
+ typedef struct configured_structure cs;
+ typedef struct specific_attribute sa;
+
+ sa
+ +----------------------------------+
+ cs | (*show)(cs *, buffer); |
+ +-----------------+ | (*store)(cs *, buffer, length); |
+ | | | |
+ | +-------------+ | | +------------------+ |
+ | | struct |-|----|------>|struct | |
+ | | config_item | | | |configfs_attribute| |
+ | +-------------+ | | +------------------+ |
+ | | +----------------------------------+
+ | data to be set | .
+ | | .
+ +-----------------+ .
+
+The file names are decided by the config item/group designer, while
+the directories in general can be named at will. A group can have
+a number of its default sub-groups created automatically.
+
+For more information on configfs please see
+`Documentation/filesystems/configfs.rst`.
+
+The concepts described above translate to USB gadgets like this:
+
+1. A gadget has its config group, which has some attributes (idVendor,
+idProduct etc) and default sub-groups (configs, functions, strings).
+Writing to the attributes causes the information to be stored in
+appropriate locations. In the configs, functions and strings sub-groups
+a user can create their sub-groups to represent configurations, functions,
+and groups of strings in a given language.
+
+2. The user creates configurations and functions, in the configurations
+creates symbolic links to functions. This information is used when the
+gadget's UDC attribute is written to, which means binding the gadget
+to the UDC. The code in drivers/usb/gadget/configfs.c iterates over
+all configurations, and in each configuration it iterates over all
+functions and binds them. This way the whole gadget is bound.
+
+3. The file drivers/usb/gadget/configfs.c contains code for
+
+ - gadget's config_group
+ - gadget's default groups (configs, functions, strings)
+ - associating functions with configurations (symlinks)
+
+4. Each USB function naturally has its own view of what it wants
+configured, so config_groups for particular functions are defined
+in the functions implementation files drivers/usb/gadget/f_*.c.
+
+5. Function's code is written in such a way that it uses
+
+usb_get_function_instance(), which, in turn, calls request_module.
+So, provided that modprobe works, modules for particular functions
+are loaded automatically. Please note that the converse is not true:
+after a gadget is disabled and torn down, the modules remain loaded.
diff --git a/Documentation/usb/gadget_hid.rst b/Documentation/usb/gadget_hid.rst
new file mode 100644
index 000000000..e623416de
--- /dev/null
+++ b/Documentation/usb/gadget_hid.rst
@@ -0,0 +1,457 @@
+===========================
+Linux USB HID gadget driver
+===========================
+
+Introduction
+============
+
+The HID Gadget driver provides emulation of USB Human Interface
+Devices (HID). The basic HID handling is done in the kernel,
+and HID reports can be sent/received through I/O on the
+/dev/hidgX character devices.
+
+For more details about HID, see the developer page on
+https://www.usb.org/developers/hidpage/
+
+Configuration
+=============
+
+g_hid is a platform driver, so to use it you need to add
+struct platform_device(s) to your platform code defining the
+HID function descriptors you want to use - E.G. something
+like::
+
+ #include <linux/platform_device.h>
+ #include <linux/usb/g_hid.h>
+
+ /* hid descriptor for a keyboard */
+ static struct hidg_func_descriptor my_hid_data = {
+ .subclass = 0, /* No subclass */
+ .protocol = 1, /* Keyboard */
+ .report_length = 8,
+ .report_desc_length = 63,
+ .report_desc = {
+ 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
+ 0x09, 0x06, /* USAGE (Keyboard) */
+ 0xa1, 0x01, /* COLLECTION (Application) */
+ 0x05, 0x07, /* USAGE_PAGE (Keyboard) */
+ 0x19, 0xe0, /* USAGE_MINIMUM (Keyboard LeftControl) */
+ 0x29, 0xe7, /* USAGE_MAXIMUM (Keyboard Right GUI) */
+ 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
+ 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */
+ 0x75, 0x01, /* REPORT_SIZE (1) */
+ 0x95, 0x08, /* REPORT_COUNT (8) */
+ 0x81, 0x02, /* INPUT (Data,Var,Abs) */
+ 0x95, 0x01, /* REPORT_COUNT (1) */
+ 0x75, 0x08, /* REPORT_SIZE (8) */
+ 0x81, 0x03, /* INPUT (Cnst,Var,Abs) */
+ 0x95, 0x05, /* REPORT_COUNT (5) */
+ 0x75, 0x01, /* REPORT_SIZE (1) */
+ 0x05, 0x08, /* USAGE_PAGE (LEDs) */
+ 0x19, 0x01, /* USAGE_MINIMUM (Num Lock) */
+ 0x29, 0x05, /* USAGE_MAXIMUM (Kana) */
+ 0x91, 0x02, /* OUTPUT (Data,Var,Abs) */
+ 0x95, 0x01, /* REPORT_COUNT (1) */
+ 0x75, 0x03, /* REPORT_SIZE (3) */
+ 0x91, 0x03, /* OUTPUT (Cnst,Var,Abs) */
+ 0x95, 0x06, /* REPORT_COUNT (6) */
+ 0x75, 0x08, /* REPORT_SIZE (8) */
+ 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
+ 0x25, 0x65, /* LOGICAL_MAXIMUM (101) */
+ 0x05, 0x07, /* USAGE_PAGE (Keyboard) */
+ 0x19, 0x00, /* USAGE_MINIMUM (Reserved) */
+ 0x29, 0x65, /* USAGE_MAXIMUM (Keyboard Application) */
+ 0x81, 0x00, /* INPUT (Data,Ary,Abs) */
+ 0xc0 /* END_COLLECTION */
+ }
+ };
+
+ static struct platform_device my_hid = {
+ .name = "hidg",
+ .id = 0,
+ .num_resources = 0,
+ .resource = 0,
+ .dev.platform_data = &my_hid_data,
+ };
+
+You can add as many HID functions as you want, only limited by
+the amount of interrupt endpoints your gadget driver supports.
+
+Configuration with configfs
+===========================
+
+Instead of adding fake platform devices and drivers in order to pass
+some data to the kernel, if HID is a part of a gadget composed with
+configfs the hidg_func_descriptor.report_desc is passed to the kernel
+by writing the appropriate stream of bytes to a configfs attribute.
+
+Send and receive HID reports
+============================
+
+HID reports can be sent/received using read/write on the
+/dev/hidgX character devices. See below for an example program
+to do this.
+
+hid_gadget_test is a small interactive program to test the HID
+gadget driver. To use, point it at a hidg device and set the
+device type (keyboard / mouse / joystick) - E.G.::
+
+ # hid_gadget_test /dev/hidg0 keyboard
+
+You are now in the prompt of hid_gadget_test. You can type any
+combination of options and values. Available options and
+values are listed at program start. In keyboard mode you can
+send up to six values.
+
+For example type: g i s t r --left-shift
+
+Hit return and the corresponding report will be sent by the
+HID gadget.
+
+Another interesting example is the caps lock test. Type
+--caps-lock and hit return. A report is then sent by the
+gadget and you should receive the host answer, corresponding
+to the caps lock LED status::
+
+ --caps-lock
+ recv report:2
+
+With this command::
+
+ # hid_gadget_test /dev/hidg1 mouse
+
+You can test the mouse emulation. Values are two signed numbers.
+
+
+Sample code::
+
+ /* hid_gadget_test */
+
+ #include <pthread.h>
+ #include <string.h>
+ #include <stdio.h>
+ #include <ctype.h>
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <unistd.h>
+
+ #define BUF_LEN 512
+
+ struct options {
+ const char *opt;
+ unsigned char val;
+ };
+
+ static struct options kmod[] = {
+ {.opt = "--left-ctrl", .val = 0x01},
+ {.opt = "--right-ctrl", .val = 0x10},
+ {.opt = "--left-shift", .val = 0x02},
+ {.opt = "--right-shift", .val = 0x20},
+ {.opt = "--left-alt", .val = 0x04},
+ {.opt = "--right-alt", .val = 0x40},
+ {.opt = "--left-meta", .val = 0x08},
+ {.opt = "--right-meta", .val = 0x80},
+ {.opt = NULL}
+ };
+
+ static struct options kval[] = {
+ {.opt = "--return", .val = 0x28},
+ {.opt = "--esc", .val = 0x29},
+ {.opt = "--bckspc", .val = 0x2a},
+ {.opt = "--tab", .val = 0x2b},
+ {.opt = "--spacebar", .val = 0x2c},
+ {.opt = "--caps-lock", .val = 0x39},
+ {.opt = "--f1", .val = 0x3a},
+ {.opt = "--f2", .val = 0x3b},
+ {.opt = "--f3", .val = 0x3c},
+ {.opt = "--f4", .val = 0x3d},
+ {.opt = "--f5", .val = 0x3e},
+ {.opt = "--f6", .val = 0x3f},
+ {.opt = "--f7", .val = 0x40},
+ {.opt = "--f8", .val = 0x41},
+ {.opt = "--f9", .val = 0x42},
+ {.opt = "--f10", .val = 0x43},
+ {.opt = "--f11", .val = 0x44},
+ {.opt = "--f12", .val = 0x45},
+ {.opt = "--insert", .val = 0x49},
+ {.opt = "--home", .val = 0x4a},
+ {.opt = "--pageup", .val = 0x4b},
+ {.opt = "--del", .val = 0x4c},
+ {.opt = "--end", .val = 0x4d},
+ {.opt = "--pagedown", .val = 0x4e},
+ {.opt = "--right", .val = 0x4f},
+ {.opt = "--left", .val = 0x50},
+ {.opt = "--down", .val = 0x51},
+ {.opt = "--kp-enter", .val = 0x58},
+ {.opt = "--up", .val = 0x52},
+ {.opt = "--num-lock", .val = 0x53},
+ {.opt = NULL}
+ };
+
+ int keyboard_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+ {
+ char *tok = strtok(buf, " ");
+ int key = 0;
+ int i = 0;
+
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ if (strcmp(tok, "--hold") == 0) {
+ *hold = 1;
+ continue;
+ }
+
+ if (key < 6) {
+ for (i = 0; kval[i].opt != NULL; i++)
+ if (strcmp(tok, kval[i].opt) == 0) {
+ report[2 + key++] = kval[i].val;
+ break;
+ }
+ if (kval[i].opt != NULL)
+ continue;
+ }
+
+ if (key < 6)
+ if (islower(tok[0])) {
+ report[2 + key++] = (tok[0] - ('a' - 0x04));
+ continue;
+ }
+
+ for (i = 0; kmod[i].opt != NULL; i++)
+ if (strcmp(tok, kmod[i].opt) == 0) {
+ report[0] = report[0] | kmod[i].val;
+ break;
+ }
+ if (kmod[i].opt != NULL)
+ continue;
+
+ if (key < 6)
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 8;
+ }
+
+ static struct options mmod[] = {
+ {.opt = "--b1", .val = 0x01},
+ {.opt = "--b2", .val = 0x02},
+ {.opt = "--b3", .val = 0x04},
+ {.opt = NULL}
+ };
+
+ int mouse_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+ {
+ char *tok = strtok(buf, " ");
+ int mvt = 0;
+ int i = 0;
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ if (strcmp(tok, "--hold") == 0) {
+ *hold = 1;
+ continue;
+ }
+
+ for (i = 0; mmod[i].opt != NULL; i++)
+ if (strcmp(tok, mmod[i].opt) == 0) {
+ report[0] = report[0] | mmod[i].val;
+ break;
+ }
+ if (mmod[i].opt != NULL)
+ continue;
+
+ if (!(tok[0] == '-' && tok[1] == '-') && mvt < 2) {
+ errno = 0;
+ report[1 + mvt++] = (char)strtol(tok, NULL, 0);
+ if (errno != 0) {
+ fprintf(stderr, "Bad value:'%s'\n", tok);
+ report[1 + mvt--] = 0;
+ }
+ continue;
+ }
+
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 3;
+ }
+
+ static struct options jmod[] = {
+ {.opt = "--b1", .val = 0x10},
+ {.opt = "--b2", .val = 0x20},
+ {.opt = "--b3", .val = 0x40},
+ {.opt = "--b4", .val = 0x80},
+ {.opt = "--hat1", .val = 0x00},
+ {.opt = "--hat2", .val = 0x01},
+ {.opt = "--hat3", .val = 0x02},
+ {.opt = "--hat4", .val = 0x03},
+ {.opt = "--hatneutral", .val = 0x04},
+ {.opt = NULL}
+ };
+
+ int joystick_fill_report(char report[8], char buf[BUF_LEN], int *hold)
+ {
+ char *tok = strtok(buf, " ");
+ int mvt = 0;
+ int i = 0;
+
+ *hold = 1;
+
+ /* set default hat position: neutral */
+ report[3] = 0x04;
+
+ for (; tok != NULL; tok = strtok(NULL, " ")) {
+
+ if (strcmp(tok, "--quit") == 0)
+ return -1;
+
+ for (i = 0; jmod[i].opt != NULL; i++)
+ if (strcmp(tok, jmod[i].opt) == 0) {
+ report[3] = (report[3] & 0xF0) | jmod[i].val;
+ break;
+ }
+ if (jmod[i].opt != NULL)
+ continue;
+
+ if (!(tok[0] == '-' && tok[1] == '-') && mvt < 3) {
+ errno = 0;
+ report[mvt++] = (char)strtol(tok, NULL, 0);
+ if (errno != 0) {
+ fprintf(stderr, "Bad value:'%s'\n", tok);
+ report[mvt--] = 0;
+ }
+ continue;
+ }
+
+ fprintf(stderr, "unknown option: %s\n", tok);
+ }
+ return 4;
+ }
+
+ void print_options(char c)
+ {
+ int i = 0;
+
+ if (c == 'k') {
+ printf(" keyboard options:\n"
+ " --hold\n");
+ for (i = 0; kmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", kmod[i].opt);
+ printf("\n keyboard values:\n"
+ " [a-z] or\n");
+ for (i = 0; kval[i].opt != NULL; i++)
+ printf("\t\t%-8s%s", kval[i].opt, i % 2 ? "\n" : "");
+ printf("\n");
+ } else if (c == 'm') {
+ printf(" mouse options:\n"
+ " --hold\n");
+ for (i = 0; mmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", mmod[i].opt);
+ printf("\n mouse values:\n"
+ " Two signed numbers\n"
+ "--quit to close\n");
+ } else {
+ printf(" joystick options:\n");
+ for (i = 0; jmod[i].opt != NULL; i++)
+ printf("\t\t%s\n", jmod[i].opt);
+ printf("\n joystick values:\n"
+ " three signed numbers\n"
+ "--quit to close\n");
+ }
+ }
+
+ int main(int argc, const char *argv[])
+ {
+ const char *filename = NULL;
+ int fd = 0;
+ char buf[BUF_LEN];
+ int cmd_len;
+ char report[8];
+ int to_send = 8;
+ int hold = 0;
+ fd_set rfds;
+ int retval, i;
+
+ if (argc < 3) {
+ fprintf(stderr, "Usage: %s devname mouse|keyboard|joystick\n",
+ argv[0]);
+ return 1;
+ }
+
+ if (argv[2][0] != 'k' && argv[2][0] != 'm' && argv[2][0] != 'j')
+ return 2;
+
+ filename = argv[1];
+
+ if ((fd = open(filename, O_RDWR, 0666)) == -1) {
+ perror(filename);
+ return 3;
+ }
+
+ print_options(argv[2][0]);
+
+ while (42) {
+
+ FD_ZERO(&rfds);
+ FD_SET(STDIN_FILENO, &rfds);
+ FD_SET(fd, &rfds);
+
+ retval = select(fd + 1, &rfds, NULL, NULL, NULL);
+ if (retval == -1 && errno == EINTR)
+ continue;
+ if (retval < 0) {
+ perror("select()");
+ return 4;
+ }
+
+ if (FD_ISSET(fd, &rfds)) {
+ cmd_len = read(fd, buf, BUF_LEN - 1);
+ printf("recv report:");
+ for (i = 0; i < cmd_len; i++)
+ printf(" %02x", buf[i]);
+ printf("\n");
+ }
+
+ if (FD_ISSET(STDIN_FILENO, &rfds)) {
+ memset(report, 0x0, sizeof(report));
+ cmd_len = read(STDIN_FILENO, buf, BUF_LEN - 1);
+
+ if (cmd_len == 0)
+ break;
+
+ buf[cmd_len - 1] = '\0';
+ hold = 0;
+
+ memset(report, 0x0, sizeof(report));
+ if (argv[2][0] == 'k')
+ to_send = keyboard_fill_report(report, buf, &hold);
+ else if (argv[2][0] == 'm')
+ to_send = mouse_fill_report(report, buf, &hold);
+ else
+ to_send = joystick_fill_report(report, buf, &hold);
+
+ if (to_send == -1)
+ break;
+
+ if (write(fd, report, to_send) != to_send) {
+ perror(filename);
+ return 5;
+ }
+ if (!hold) {
+ memset(report, 0x0, sizeof(report));
+ if (write(fd, report, to_send) != to_send) {
+ perror(filename);
+ return 6;
+ }
+ }
+ }
+ }
+
+ close(fd);
+ return 0;
+ }
diff --git a/Documentation/usb/gadget_multi.rst b/Documentation/usb/gadget_multi.rst
new file mode 100644
index 000000000..3a22c1b2f
--- /dev/null
+++ b/Documentation/usb/gadget_multi.rst
@@ -0,0 +1,165 @@
+==============================
+Multifunction Composite Gadget
+==============================
+
+Overview
+========
+
+The Multifunction Composite Gadget (or g_multi) is a composite gadget
+that makes extensive use of the composite framework to provide
+a... multifunction gadget.
+
+In it's standard configuration it provides a single USB configuration
+with RNDIS[1] (that is Ethernet), USB CDC[2] ACM (that is serial) and
+USB Mass Storage functions.
+
+A CDC ECM (Ethernet) function may be turned on via a Kconfig option
+and RNDIS can be turned off. If they are both enabled the gadget will
+have two configurations -- one with RNDIS and another with CDC ECM[3].
+
+Please note that if you use non-standard configuration (that is enable
+CDC ECM) you may need to change vendor and/or product ID.
+
+Host drivers
+============
+
+To make use of the gadget one needs to make it work on host side --
+without that there's no hope of achieving anything with the gadget.
+As one might expect, things one need to do very from system to system.
+
+Linux host drivers
+------------------
+
+Since the gadget uses standard composite framework and appears as such
+to Linux host it does not need any additional drivers on Linux host
+side. All the functions are handled by respective drivers developed
+for them.
+
+This is also true for two configuration set-up with RNDIS
+configuration being the first one. Linux host will use the second
+configuration with CDC ECM which should work better under Linux.
+
+Windows host drivers
+--------------------
+
+For the gadget to work under Windows two conditions have to be met:
+
+Detecting as composite gadget
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+First of all, Windows need to detect the gadget as an USB composite
+gadget which on its own have some conditions[4]. If they are met,
+Windows lets USB Generic Parent Driver[5] handle the device which then
+tries to match drivers for each individual interface (sort of, don't
+get into too many details).
+
+The good news is: you do not have to worry about most of the
+conditions!
+
+The only thing to worry is that the gadget has to have a single
+configuration so a dual RNDIS and CDC ECM gadget won't work unless you
+create a proper INF -- and of course, if you do submit it!
+
+Installing drivers for each function
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The other, trickier thing is making Windows install drivers for each
+individual function.
+
+For mass storage it is trivial since Windows detect it's an interface
+implementing USB Mass Storage class and selects appropriate driver.
+
+Things are harder with RDNIS and CDC ACM.
+
+RNDIS
+.....
+
+To make Windows select RNDIS drivers for the first function in the
+gadget, one needs to use the [[file:linux.inf]] file provided with this
+document. It "attaches" Window's RNDIS driver to the first interface
+of the gadget.
+
+Please note, that while testing we encountered some issues[6] when
+RNDIS was not the first interface. You do not need to worry abut it
+unless you are trying to develop your own gadget in which case watch
+out for this bug.
+
+CDC ACM
+.......
+
+Similarly, [[file:linux-cdc-acm.inf]] is provided for CDC ACM.
+
+Customising the gadget
+......................
+
+If you intend to hack the g_multi gadget be advised that rearranging
+functions will obviously change interface numbers for each of the
+functionality. As an effect provided INFs won't work since they have
+interface numbers hard-coded in them (it's not hard to change those
+though[7]).
+
+This also means, that after experimenting with g_multi and changing
+provided functions one should change gadget's vendor and/or product ID
+so there will be no collision with other customised gadgets or the
+original gadget.
+
+Failing to comply may cause brain damage after wondering for hours why
+things don't work as intended before realising Windows have cached
+some drivers information (changing USB port may sometimes help plus
+you might try using USBDeview[8] to remove the phantom device).
+
+INF testing
+...........
+
+Provided INF files have been tested on Windows XP SP3, Windows Vista
+and Windows 7, all 32-bit versions. It should work on 64-bit versions
+as well. It most likely won't work on Windows prior to Windows XP
+SP2.
+
+Other systems
+-------------
+
+At this moment, drivers for any other systems have not been tested.
+Knowing how MacOS is based on BSD and BSD is an Open Source it is
+believed that it should (read: "I have no idea whether it will") work
+out-of-the-box.
+
+For more exotic systems I have even less to say...
+
+Any testing and drivers *are* *welcome*!
+
+Authors
+=======
+
+This document has been written by Michal Nazarewicz
+([[mailto:mina86@mina86.com]]). INF files have been hacked with
+support of Marek Szyprowski ([[mailto:m.szyprowski@samsung.com]]) and
+Xiaofan Chen ([[mailto:xiaofanc@gmail.com]]) basing on the MS RNDIS
+template[9], Microchip's CDC ACM INF file and David Brownell's
+([[mailto:dbrownell@users.sourceforge.net]]) original INF files.
+
+Footnotes
+=========
+
+[1] Remote Network Driver Interface Specification,
+[[https://msdn.microsoft.com/en-us/library/ee484414.aspx]].
+
+[2] Communications Device Class Abstract Control Model, spec for this
+and other USB classes can be found at
+[[http://www.usb.org/developers/devclass_docs/]].
+
+[3] CDC Ethernet Control Model.
+
+[4] [[https://msdn.microsoft.com/en-us/library/ff537109(v=VS.85).aspx]]
+
+[5] [[https://msdn.microsoft.com/en-us/library/ff539234(v=VS.85).aspx]]
+
+[6] To put it in some other nice words, Windows failed to respond to
+any user input.
+
+[7] You may find [[http://www.cygnal.org/ubb/Forum9/HTML/001050.html]]
+useful.
+
+[8] https://www.nirsoft.net/utils/usb_devices_view.html
+
+[9] [[https://msdn.microsoft.com/en-us/library/ff570620.aspx]]
diff --git a/Documentation/usb/gadget_printer.rst b/Documentation/usb/gadget_printer.rst
new file mode 100644
index 000000000..5e5516c69
--- /dev/null
+++ b/Documentation/usb/gadget_printer.rst
@@ -0,0 +1,523 @@
+===============================
+Linux USB Printer Gadget Driver
+===============================
+
+06/04/2007
+
+Copyright (C) 2007 Craig W. Nadler <craig@nadler.us>
+
+
+
+General
+=======
+
+This driver may be used if you are writing printer firmware using Linux as
+the embedded OS. This driver has nothing to do with using a printer with
+your Linux host system.
+
+You will need a USB device controller and a Linux driver for it that accepts
+a gadget / "device class" driver using the Linux USB Gadget API. After the
+USB device controller driver is loaded then load the printer gadget driver.
+This will present a printer interface to the USB Host that your USB Device
+port is connected to.
+
+This driver is structured for printer firmware that runs in user mode. The
+user mode printer firmware will read and write data from the kernel mode
+printer gadget driver using a device file. The printer returns a printer status
+byte when the USB HOST sends a device request to get the printer status. The
+user space firmware can read or write this status byte using a device file
+/dev/g_printer . Both blocking and non-blocking read/write calls are supported.
+
+
+
+
+Howto Use This Driver
+=====================
+
+To load the USB device controller driver and the printer gadget driver. The
+following example uses the Netchip 2280 USB device controller driver::
+
+ modprobe net2280
+ modprobe g_printer
+
+
+The follow command line parameter can be used when loading the printer gadget
+(ex: modprobe g_printer idVendor=0x0525 idProduct=0xa4a8 ):
+
+idVendor
+ This is the Vendor ID used in the device descriptor. The default is
+ the Netchip vendor id 0x0525. YOU MUST CHANGE TO YOUR OWN VENDOR ID
+ BEFORE RELEASING A PRODUCT. If you plan to release a product and don't
+ already have a Vendor ID please see www.usb.org for details on how to
+ get one.
+
+idProduct
+ This is the Product ID used in the device descriptor. The default
+ is 0xa4a8, you should change this to an ID that's not used by any of
+ your other USB products if you have any. It would be a good idea to
+ start numbering your products starting with say 0x0001.
+
+bcdDevice
+ This is the version number of your product. It would be a good idea
+ to put your firmware version here.
+
+iManufacturer
+ A string containing the name of the Vendor.
+
+iProduct
+ A string containing the Product Name.
+
+iSerialNum
+ A string containing the Serial Number. This should be changed for
+ each unit of your product.
+
+iPNPstring
+ The PNP ID string used for this printer. You will want to set
+ either on the command line or hard code the PNP ID string used for
+ your printer product.
+
+qlen
+ The number of 8k buffers to use per endpoint. The default is 10, you
+ should tune this for your product. You may also want to tune the
+ size of each buffer for your product.
+
+
+
+
+Using The Example Code
+======================
+
+This example code talks to stdout, instead of a print engine.
+
+To compile the test code below:
+
+1) save it to a file called prn_example.c
+2) compile the code with the follow command::
+
+ gcc prn_example.c -o prn_example
+
+
+
+To read printer data from the host to stdout::
+
+ # prn_example -read_data
+
+
+To write printer data from a file (data_file) to the host::
+
+ # cat data_file | prn_example -write_data
+
+
+To get the current printer status for the gadget driver:::
+
+ # prn_example -get_status
+
+ Printer status is:
+ Printer is NOT Selected
+ Paper is Out
+ Printer OK
+
+
+To set printer to Selected/On-line::
+
+ # prn_example -selected
+
+
+To set printer to Not Selected/Off-line::
+
+ # prn_example -not_selected
+
+
+To set paper status to paper out::
+
+ # prn_example -paper_out
+
+
+To set paper status to paper loaded::
+
+ # prn_example -paper_loaded
+
+
+To set error status to printer OK::
+
+ # prn_example -no_error
+
+
+To set error status to ERROR::
+
+ # prn_example -error
+
+
+
+
+Example Code
+============
+
+::
+
+
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <fcntl.h>
+ #include <linux/poll.h>
+ #include <sys/ioctl.h>
+ #include <linux/usb/g_printer.h>
+
+ #define PRINTER_FILE "/dev/g_printer"
+ #define BUF_SIZE 512
+
+
+ /*
+ * 'usage()' - Show program usage.
+ */
+
+ static void
+ usage(const char *option) /* I - Option string or NULL */
+ {
+ if (option) {
+ fprintf(stderr,"prn_example: Unknown option \"%s\"!\n",
+ option);
+ }
+
+ fputs("\n", stderr);
+ fputs("Usage: prn_example -[options]\n", stderr);
+ fputs("Options:\n", stderr);
+ fputs("\n", stderr);
+ fputs("-get_status Get the current printer status.\n", stderr);
+ fputs("-selected Set the selected status to selected.\n", stderr);
+ fputs("-not_selected Set the selected status to NOT selected.\n",
+ stderr);
+ fputs("-error Set the error status to error.\n", stderr);
+ fputs("-no_error Set the error status to NO error.\n", stderr);
+ fputs("-paper_out Set the paper status to paper out.\n", stderr);
+ fputs("-paper_loaded Set the paper status to paper loaded.\n",
+ stderr);
+ fputs("-read_data Read printer data from driver.\n", stderr);
+ fputs("-write_data Write printer sata to driver.\n", stderr);
+ fputs("-NB_read_data (Non-Blocking) Read printer data from driver.\n",
+ stderr);
+ fputs("\n\n", stderr);
+
+ exit(1);
+ }
+
+
+ static int
+ read_printer_data()
+ {
+ struct pollfd fd[1];
+
+ /* Open device file for printer gadget. */
+ fd[0].fd = open(PRINTER_FILE, O_RDWR);
+ if (fd[0].fd < 0) {
+ printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ }
+
+ fd[0].events = POLLIN | POLLRDNORM;
+
+ while (1) {
+ static char buf[BUF_SIZE];
+ int bytes_read;
+ int retval;
+
+ /* Wait for up to 1 second for data. */
+ retval = poll(fd, 1, 1000);
+
+ if (retval && (fd[0].revents & POLLRDNORM)) {
+
+ /* Read data from printer gadget driver. */
+ bytes_read = read(fd[0].fd, buf, BUF_SIZE);
+
+ if (bytes_read < 0) {
+ printf("Error %d reading from %s\n",
+ fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ } else if (bytes_read > 0) {
+ /* Write data to standard OUTPUT (stdout). */
+ fwrite(buf, 1, bytes_read, stdout);
+ fflush(stdout);
+ }
+
+ }
+
+ }
+
+ /* Close the device file. */
+ close(fd[0].fd);
+
+ return 0;
+ }
+
+
+ static int
+ write_printer_data()
+ {
+ struct pollfd fd[1];
+
+ /* Open device file for printer gadget. */
+ fd[0].fd = open (PRINTER_FILE, O_RDWR);
+ if (fd[0].fd < 0) {
+ printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ }
+
+ fd[0].events = POLLOUT | POLLWRNORM;
+
+ while (1) {
+ int retval;
+ static char buf[BUF_SIZE];
+ /* Read data from standard INPUT (stdin). */
+ int bytes_read = fread(buf, 1, BUF_SIZE, stdin);
+
+ if (!bytes_read) {
+ break;
+ }
+
+ while (bytes_read) {
+
+ /* Wait for up to 1 second to sent data. */
+ retval = poll(fd, 1, 1000);
+
+ /* Write data to printer gadget driver. */
+ if (retval && (fd[0].revents & POLLWRNORM)) {
+ retval = write(fd[0].fd, buf, bytes_read);
+ if (retval < 0) {
+ printf("Error %d writing to %s\n",
+ fd[0].fd,
+ PRINTER_FILE);
+ close(fd[0].fd);
+ return(-1);
+ } else {
+ bytes_read -= retval;
+ }
+
+ }
+
+ }
+
+ }
+
+ /* Wait until the data has been sent. */
+ fsync(fd[0].fd);
+
+ /* Close the device file. */
+ close(fd[0].fd);
+
+ return 0;
+ }
+
+
+ static int
+ read_NB_printer_data()
+ {
+ int fd;
+ static char buf[BUF_SIZE];
+ int bytes_read;
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR|O_NONBLOCK);
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ while (1) {
+ /* Read data from printer gadget driver. */
+ bytes_read = read(fd, buf, BUF_SIZE);
+ if (bytes_read <= 0) {
+ break;
+ }
+
+ /* Write data to standard OUTPUT (stdout). */
+ fwrite(buf, 1, bytes_read, stdout);
+ fflush(stdout);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return 0;
+ }
+
+
+ static int
+ get_printer_status()
+ {
+ int retval;
+ int fd;
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR);
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ /* Make the IOCTL call. */
+ retval = ioctl(fd, GADGET_GET_PRINTER_STATUS);
+ if (retval < 0) {
+ fprintf(stderr, "ERROR: Failed to set printer status\n");
+ return(-1);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return(retval);
+ }
+
+
+ static int
+ set_printer_status(unsigned char buf, int clear_printer_status_bit)
+ {
+ int retval;
+ int fd;
+
+ retval = get_printer_status();
+ if (retval < 0) {
+ fprintf(stderr, "ERROR: Failed to get printer status\n");
+ return(-1);
+ }
+
+ /* Open device file for printer gadget. */
+ fd = open(PRINTER_FILE, O_RDWR);
+
+ if (fd < 0) {
+ printf("Error %d opening %s\n", fd, PRINTER_FILE);
+ close(fd);
+ return(-1);
+ }
+
+ if (clear_printer_status_bit) {
+ retval &= ~buf;
+ } else {
+ retval |= buf;
+ }
+
+ /* Make the IOCTL call. */
+ if (ioctl(fd, GADGET_SET_PRINTER_STATUS, (unsigned char)retval)) {
+ fprintf(stderr, "ERROR: Failed to set printer status\n");
+ return(-1);
+ }
+
+ /* Close the device file. */
+ close(fd);
+
+ return 0;
+ }
+
+
+ static int
+ display_printer_status()
+ {
+ char printer_status;
+
+ printer_status = get_printer_status();
+ if (printer_status < 0) {
+ fprintf(stderr, "ERROR: Failed to get printer status\n");
+ return(-1);
+ }
+
+ printf("Printer status is:\n");
+ if (printer_status & PRINTER_SELECTED) {
+ printf(" Printer is Selected\n");
+ } else {
+ printf(" Printer is NOT Selected\n");
+ }
+ if (printer_status & PRINTER_PAPER_EMPTY) {
+ printf(" Paper is Out\n");
+ } else {
+ printf(" Paper is Loaded\n");
+ }
+ if (printer_status & PRINTER_NOT_ERROR) {
+ printf(" Printer OK\n");
+ } else {
+ printf(" Printer ERROR\n");
+ }
+
+ return(0);
+ }
+
+
+ int
+ main(int argc, char *argv[])
+ {
+ int i; /* Looping var */
+ int retval = 0;
+
+ /* No Args */
+ if (argc == 1) {
+ usage(0);
+ exit(0);
+ }
+
+ for (i = 1; i < argc && !retval; i ++) {
+
+ if (argv[i][0] != '-') {
+ continue;
+ }
+
+ if (!strcmp(argv[i], "-get_status")) {
+ if (display_printer_status()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-paper_loaded")) {
+ if (set_printer_status(PRINTER_PAPER_EMPTY, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-paper_out")) {
+ if (set_printer_status(PRINTER_PAPER_EMPTY, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-selected")) {
+ if (set_printer_status(PRINTER_SELECTED, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-not_selected")) {
+ if (set_printer_status(PRINTER_SELECTED, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-error")) {
+ if (set_printer_status(PRINTER_NOT_ERROR, 1)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-no_error")) {
+ if (set_printer_status(PRINTER_NOT_ERROR, 0)) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-read_data")) {
+ if (read_printer_data()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-write_data")) {
+ if (write_printer_data()) {
+ retval = 1;
+ }
+
+ } else if (!strcmp(argv[i], "-NB_read_data")) {
+ if (read_NB_printer_data()) {
+ retval = 1;
+ }
+
+ } else {
+ usage(argv[i]);
+ retval = 1;
+ }
+ }
+
+ exit(retval);
+ }
diff --git a/Documentation/usb/gadget_serial.rst b/Documentation/usb/gadget_serial.rst
new file mode 100644
index 000000000..dce8bc1fb
--- /dev/null
+++ b/Documentation/usb/gadget_serial.rst
@@ -0,0 +1,289 @@
+===============================
+Linux Gadget Serial Driver v2.0
+===============================
+
+11/20/2004
+
+(updated 8-May-2008 for v2.3)
+
+
+License and Disclaimer
+----------------------
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of
+the License, or (at your option) any later version.
+
+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., 59 Temple Place, Suite 330, Boston,
+MA 02111-1307 USA.
+
+This document and the gadget serial driver itself are
+Copyright (C) 2004 by Al Borchers (alborchers@steinerpoint.com).
+
+If you have questions, problems, or suggestions for this driver
+please contact Al Borchers at alborchers@steinerpoint.com.
+
+
+Prerequisites
+-------------
+Versions of the gadget serial driver are available for the
+2.4 Linux kernels, but this document assumes you are using
+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
+Windows and know how to configure and build Linux kernels, run
+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
+--------
+The gadget serial driver is a Linux USB gadget driver, a USB device
+side driver. It runs on a Linux system that has USB device side
+hardware; for example, a PDA, an embedded Linux system, or a PC
+with a USB development card.
+
+The gadget serial driver talks over USB to either a CDC ACM driver
+or a generic USB serial driver running on a host PC::
+
+ Host
+ --------------------------------------
+ | Host-Side CDC ACM USB Host |
+ | Operating | or | Controller | USB
+ | System | Generic USB | Driver |--------
+ | (Linux or | Serial | and | |
+ | Windows) Driver USB Stack | |
+ -------------------------------------- |
+ |
+ |
+ |
+ Gadget |
+ -------------------------------------- |
+ | Gadget USB Periph. | |
+ | Device-Side | Gadget | Controller | |
+ | Linux | Serial | Driver |--------
+ | Operating | Driver | and |
+ | System USB Stack |
+ --------------------------------------
+
+On the device-side Linux system, the gadget serial driver looks
+like a serial device.
+
+On the host-side system, the gadget serial device looks like a
+CDC ACM compliant class device or a simple vendor specific device
+with bulk in and bulk out endpoints, and it is treated similarly
+to other serial devices.
+
+The host side driver can potentially be any ACM compliant driver
+or any driver that can talk to a device with a simple bulk in/out
+interface. Gadget serial has been tested with the Linux ACM driver,
+the Windows usbser.sys ACM driver, and the Linux USB generic serial
+driver.
+
+With the gadget serial driver and the host side ACM or generic
+serial driver running, you should be able to communicate between
+the host and the gadget side systems as if they were connected by a
+serial cable.
+
+The gadget serial driver only provides simple unreliable data
+communication. It does not yet handle flow control or many other
+features of normal serial devices.
+
+
+Installing the Gadget Serial Driver
+-----------------------------------
+To use the gadget serial driver you must configure the Linux gadget
+side kernel for "Support for USB Gadgets", for a "USB Peripheral
+Controller" (for example, net2280), and for the "Serial Gadget"
+driver. All this are listed under "USB Gadget Support" when
+configuring the kernel. Then rebuild and install the kernel or
+modules.
+
+Then you must load the gadget serial driver. To load it as an
+ACM device (recommended for interoperability), do this::
+
+ modprobe g_serial
+
+To load it as a vendor specific bulk in/out device, do this::
+
+ modprobe g_serial use_acm=0
+
+This will also automatically load the underlying gadget peripheral
+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
+Linux generic serial driver on the host side. Follow the appropriate
+instructions below to install the host side driver.
+
+
+Installing the Windows Host ACM Driver
+--------------------------------------
+To use the Windows ACM driver you must have the "linux-cdc-acm.inf"
+file (provided along this document) which supports all recent versions
+of Windows.
+
+When the gadget serial driver is loaded and the USB device connected
+to the Windows host with a USB cable, Windows should recognize the
+gadget serial device and ask for a driver. Tell Windows to find the
+driver in the folder that contains the "linux-cdc-acm.inf" file.
+
+For example, on Windows XP, when the gadget serial device is first
+plugged in, the "Found New Hardware Wizard" starts up. Select
+"Install from a list or specific location (Advanced)", then on the
+next screen select "Include this location in the search" and enter the
+path or browse to the folder containing the "linux-cdc-acm.inf" file.
+Windows will complain that the Gadget Serial driver has not passed
+Windows Logo testing, but select "Continue anyway" and finish the
+driver installation.
+
+On Windows XP, in the "Device Manager" (under "Control Panel",
+"System", "Hardware") expand the "Ports (COM & LPT)" entry and you
+should see "Gadget Serial" listed as the driver for one of the COM
+ports.
+
+To uninstall the Windows XP driver for "Gadget Serial", right click
+on the "Gadget Serial" entry in the "Device Manager" and select
+"Uninstall".
+
+
+Installing the Linux Host ACM Driver
+------------------------------------
+To use the Linux ACM driver you must configure the Linux host side
+kernel for "Support for Host-side USB" and for "USB Modem (CDC ACM)
+support".
+
+Once the gadget serial driver is loaded and the USB device connected
+to the Linux host with a USB cable, the host system should recognize
+the gadget serial device. For example, the command::
+
+ cat /sys/kernel/debug/usb/devices
+
+should show something like this:::
+
+ T: Bus=01 Lev=01 Prnt=01 Port=01 Cnt=02 Dev#= 5 Spd=480 MxCh= 0
+ D: Ver= 2.00 Cls=02(comm.) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
+ P: Vendor=0525 ProdID=a4a7 Rev= 2.01
+ S: Manufacturer=Linux 2.6.8.1 with net2280
+ S: Product=Gadget Serial
+ S: SerialNumber=0
+ C:* #Ifs= 2 Cfg#= 2 Atr=c0 MxPwr= 2mA
+ I: If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=acm
+ E: Ad=83(I) Atr=03(Int.) MxPS= 8 Ivl=32ms
+ I: If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=acm
+ E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
+ E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
+
+If the host side Linux system is configured properly, the ACM driver
+should be loaded automatically. The command "lsmod" should show the
+"acm" module is loaded.
+
+
+Installing the Linux Host Generic USB Serial Driver
+---------------------------------------------------
+To use the Linux generic USB serial driver you must configure the
+Linux host side kernel for "Support for Host-side USB", for "USB
+Serial Converter support", and for the "USB Generic Serial Driver".
+
+Once the gadget serial driver is loaded and the USB device connected
+to the Linux host with a USB cable, the host system should recognize
+the gadget serial device. For example, the command::
+
+ cat /sys/kernel/debug/usb/devices
+
+should show something like this:::
+
+ T: Bus=01 Lev=01 Prnt=01 Port=01 Cnt=02 Dev#= 6 Spd=480 MxCh= 0
+ D: Ver= 2.00 Cls=ff(vend.) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
+ P: Vendor=0525 ProdID=a4a6 Rev= 2.01
+ S: Manufacturer=Linux 2.6.8.1 with net2280
+ S: Product=Gadget Serial
+ S: SerialNumber=0
+ C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr= 2mA
+ I: If#= 0 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=serial
+ E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
+ E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
+
+You must load the usbserial driver and explicitly set its parameters
+to configure it to recognize the gadget serial device, like this::
+
+ echo 0x0525 0xA4A6 >/sys/bus/usb-serial/drivers/generic/new_id
+
+The legacy way is to use module parameters::
+
+ modprobe usbserial vendor=0x0525 product=0xA4A6
+
+If everything is working, usbserial will print a message in the
+system log saying something like "Gadget Serial converter now
+attached to ttyUSB0".
+
+
+Testing with Minicom or HyperTerminal
+-------------------------------------
+Once the gadget serial driver and the host driver are both installed,
+and a USB cable connects the gadget device to the host, you should
+be able to communicate over USB between the gadget and host systems.
+You can use minicom or HyperTerminal to try this out.
+
+On the gadget side run "minicom -s" to configure a new minicom
+session. Under "Serial port setup" set "/dev/ttygserial" as the
+"Serial Device". Set baud rate, data bits, parity, and stop bits,
+to 9600, 8, none, and 1--these settings mostly do not matter.
+Under "Modem and dialing" erase all the modem and dialing strings.
+
+On a Linux host running the ACM driver, configure minicom similarly
+but use "/dev/ttyACM0" as the "Serial Device". (If you have other
+ACM devices connected, change the device name appropriately.)
+
+On a Linux host running the USB generic serial driver, configure
+minicom similarly, but use "/dev/ttyUSB0" as the "Serial Device".
+(If you have other USB serial devices connected, change the device
+name appropriately.)
+
+On a Windows host configure a new HyperTerminal session to use the
+COM port assigned to Gadget Serial. The "Port Settings" will be
+set automatically when HyperTerminal connects to the gadget serial
+device, so you can leave them set to the default values--these
+settings mostly do not matter.
+
+With minicom configured and running on the gadget side and with
+minicom or HyperTerminal configured and running on the host side,
+you should be able to send data back and forth between the gadget
+side and host side systems. Anything you type on the terminal
+window on the gadget side should appear in the terminal window on
+the host side and vice versa.
diff --git a/Documentation/usb/index.rst b/Documentation/usb/index.rst
new file mode 100644
index 000000000..b656c9be2
--- /dev/null
+++ b/Documentation/usb/index.rst
@@ -0,0 +1,38 @@
+===========
+USB support
+===========
+
+.. toctree::
+ :maxdepth: 1
+
+ acm
+ authorization
+ chipidea
+ dwc3
+ ehci
+ functionfs
+ gadget_configfs
+ gadget_hid
+ gadget_multi
+ gadget_printer
+ gadget_serial
+ gadget-testing
+ iuu_phoenix
+ mass-storage
+ misc_usbsevseg
+ mtouchusb
+ ohci
+ raw-gadget
+ usbip_protocol
+ usbmon
+ usb-serial
+
+ usb-help
+ text_files
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/usb/iuu_phoenix.rst b/Documentation/usb/iuu_phoenix.rst
new file mode 100644
index 000000000..b76268728
--- /dev/null
+++ b/Documentation/usb/iuu_phoenix.rst
@@ -0,0 +1,94 @@
+=============================
+Infinity Usb Unlimited Readme
+=============================
+
+Hi all,
+
+
+This module provide a serial interface to use your
+IUU unit in phoenix mode. Loading this module will
+bring a ttyUSB[0-x] interface. This driver must be
+used by your favorite application to pilot the IUU
+
+This driver is still in beta stage, so bugs can
+occur and your system may freeze. As far I now,
+I never had any problem with it, but I'm not a real
+guru, so don't blame me if your system is unstable
+
+You can plug more than one IUU. Every unit will
+have his own device file(/dev/ttyUSB0,/dev/ttyUSB1,...)
+
+
+
+How to tune the reader speed?
+=============================
+
+ A few parameters can be used at load time
+ To use parameters, just unload the module if it is
+ already loaded and use modprobe iuu_phoenix param=value.
+ In case of prebuilt module, use the command
+ insmod iuu_phoenix param=value.
+
+ Example::
+
+ modprobe iuu_phoenix clockmode=3
+
+ The parameters are:
+
+clockmode:
+ 1=3Mhz579,2=3Mhz680,3=6Mhz (int)
+boost:
+ overclock boost percent 100 to 500 (int)
+cdmode:
+ Card detect mode
+ 0=none, 1=CD, 2=!CD, 3=DSR, 4=!DSR, 5=CTS, 6=!CTS, 7=RING, 8=!RING (int)
+xmas:
+ xmas color enabled or not (bool)
+debug:
+ Debug enabled or not (bool)
+
+- clockmode will provide 3 different base settings commonly adopted by
+ different software:
+
+ 1. 3Mhz579
+ 2. 3Mhz680
+ 3. 6Mhz
+
+- boost provide a way to overclock the reader ( my favorite :-) )
+ For example to have best performance than a simple clockmode=3, try this::
+
+ modprobe boost=195
+
+ This will put the reader in a base of 3Mhz579 but boosted a 195 % !
+ the real clock will be now : 6979050 Hz ( 6Mhz979 ) and will increase
+ the speed to a score 10 to 20% better than the simple clockmode=3 !!!
+
+
+- cdmode permit to setup the signal used to inform the userland ( ioctl answer )
+ if the card is present or not. Eight signals are possible.
+
+- xmas is completely useless except for your eyes. This is one of my friend who was
+ so sad to have a nice device like the iuu without seeing all color range available.
+ So I have added this option to permit him to see a lot of color ( each activity change the color
+ and the frequency randomly )
+
+- debug will produce a lot of debugging messages...
+
+
+Last notes
+==========
+
+ Don't worry about the serial settings, the serial emulation
+ is an abstraction, so use any speed or parity setting will
+ work. ( This will not change anything ).Later I will perhaps
+ use this settings to deduce de boost but is that feature
+ really necessary ?
+ The autodetect feature used is the serial CD. If that doesn't
+ work for your software, disable detection mechanism in it.
+
+
+ Have fun !
+
+ Alain Degreffe
+
+ eczema(at)ecze.com
diff --git a/Documentation/usb/linux-cdc-acm.inf b/Documentation/usb/linux-cdc-acm.inf
new file mode 100644
index 000000000..f0ffc27d4
--- /dev/null
+++ b/Documentation/usb/linux-cdc-acm.inf
@@ -0,0 +1,107 @@
+; Windows USB CDC ACM Setup File
+
+; Based on INF template which was:
+; Copyright (c) 2000 Microsoft Corporation
+; Copyright (c) 2007 Microchip Technology Inc.
+; likely to be covered by the MLPL as found at:
+; <http://msdn.microsoft.com/en-us/cc300389.aspx#MLPL>.
+; For use only on Windows operating systems.
+
+[Version]
+Signature="$Windows NT$"
+Class=Ports
+ClassGuid={4D36E978-E325-11CE-BFC1-08002BE10318}
+Provider=%Linux%
+DriverVer=11/15/2007,5.1.2600.0
+
+[Manufacturer]
+%Linux%=DeviceList, NTamd64
+
+[DestinationDirs]
+DefaultDestDir=12
+
+
+;------------------------------------------------------------------------------
+; Windows 2000/XP/Vista-32bit Sections
+;------------------------------------------------------------------------------
+
+[DriverInstall.nt]
+include=mdmcpq.inf
+CopyFiles=DriverCopyFiles.nt
+AddReg=DriverInstall.nt.AddReg
+
+[DriverCopyFiles.nt]
+usbser.sys,,,0x20
+
+[DriverInstall.nt.AddReg]
+HKR,,DevLoader,,*ntkern
+HKR,,NTMPDriver,,USBSER.sys
+HKR,,EnumPropPages32,,"MsPorts.dll,SerialPortPropPageProvider"
+
+[DriverInstall.nt.Services]
+AddService=usbser, 0x00000002, DriverService.nt
+
+[DriverService.nt]
+DisplayName=%SERVICE%
+ServiceType=1
+StartType=3
+ErrorControl=1
+ServiceBinary=%12%\USBSER.sys
+
+;------------------------------------------------------------------------------
+; Vista-64bit Sections
+;------------------------------------------------------------------------------
+
+[DriverInstall.NTamd64]
+include=mdmcpq.inf
+CopyFiles=DriverCopyFiles.NTamd64
+AddReg=DriverInstall.NTamd64.AddReg
+
+[DriverCopyFiles.NTamd64]
+USBSER.sys,,,0x20
+
+[DriverInstall.NTamd64.AddReg]
+HKR,,DevLoader,,*ntkern
+HKR,,NTMPDriver,,USBSER.sys
+HKR,,EnumPropPages32,,"MsPorts.dll,SerialPortPropPageProvider"
+
+[DriverInstall.NTamd64.Services]
+AddService=usbser, 0x00000002, DriverService.NTamd64
+
+[DriverService.NTamd64]
+DisplayName=%SERVICE%
+ServiceType=1
+StartType=3
+ErrorControl=1
+ServiceBinary=%12%\USBSER.sys
+
+
+;------------------------------------------------------------------------------
+; Vendor and Product ID Definitions
+;------------------------------------------------------------------------------
+; When developing your USB device, the VID and PID used in the PC side
+; application program and the firmware on the microcontroller must match.
+; Modify the below line to use your VID and PID. Use the format as shown
+; below.
+; Note: One INF file can be used for multiple devices with different
+; VID and PIDs. For each supported device, append
+; ",USB\VID_xxxx&PID_yyyy" to the end of the line.
+;------------------------------------------------------------------------------
+[SourceDisksFiles]
+[SourceDisksNames]
+[DeviceList]
+%DESCRIPTION%=DriverInstall, USB\VID_0525&PID_A4A7, USB\VID_1D6B&PID_0104&MI_02, USB\VID_1D6B&PID_0106&MI_00
+
+[DeviceList.NTamd64]
+%DESCRIPTION%=DriverInstall, USB\VID_0525&PID_A4A7, USB\VID_1D6B&PID_0104&MI_02, USB\VID_1D6B&PID_0106&MI_00
+
+
+;------------------------------------------------------------------------------
+; String Definitions
+;------------------------------------------------------------------------------
+;Modify these strings to customize your device
+;------------------------------------------------------------------------------
+[Strings]
+Linux = "Linux Developer Community"
+DESCRIPTION = "Gadget Serial"
+SERVICE = "USB RS-232 Emulation Driver"
diff --git a/Documentation/usb/linux.inf b/Documentation/usb/linux.inf
new file mode 100644
index 000000000..c569ac6be
--- /dev/null
+++ b/Documentation/usb/linux.inf
@@ -0,0 +1,66 @@
+; Based on template INF file found at
+; <https://msdn.microsoft.com/en-us/library/ff570620.aspx>
+; which was:
+; Copyright (c) Microsoft Corporation
+; and released under the MLPL as found at:
+; <http://msdn.microsoft.com/en-us/cc300389.aspx#MLPL>.
+; For use only on Windows operating systems.
+
+[Version]
+Signature = "$Windows NT$"
+Class = Net
+ClassGUID = {4d36e972-e325-11ce-bfc1-08002be10318}
+Provider = %Linux%
+DriverVer = 06/21/2006,6.0.6000.16384
+
+[Manufacturer]
+%Linux% = LinuxDevices,NTx86,NTamd64,NTia64
+
+; Decoration for x86 architecture
+[LinuxDevices.NTx86]
+%LinuxDevice% = RNDIS.NT.5.1, USB\VID_0525&PID_a4a2, USB\VID_1d6b&PID_0104&MI_00
+
+; Decoration for x64 architecture
+[LinuxDevices.NTamd64]
+%LinuxDevice% = RNDIS.NT.5.1, USB\VID_0525&PID_a4a2, USB\VID_1d6b&PID_0104&MI_00
+
+; Decoration for ia64 architecture
+[LinuxDevices.NTia64]
+%LinuxDevice% = RNDIS.NT.5.1, USB\VID_0525&PID_a4a2, USB\VID_1d6b&PID_0104&MI_00
+
+;@@@ This is the common setting for setup
+[ControlFlags]
+ExcludeFromSelect=*
+
+; DDInstall section
+; References the in-build Netrndis.inf
+[RNDIS.NT.5.1]
+Characteristics = 0x84 ; NCF_PHYSICAL + NCF_HAS_UI
+BusType = 15
+; NEVER REMOVE THE FOLLOWING REFERENCE FOR NETRNDIS.INF
+include = netrndis.inf
+needs = Usb_Rndis.ndi
+AddReg = Rndis_AddReg_Vista
+
+; DDInstal.Services section
+[RNDIS.NT.5.1.Services]
+include = netrndis.inf
+needs = Usb_Rndis.ndi.Services
+
+; Optional registry settings. You can modify as needed.
+[RNDIS_AddReg_Vista]
+HKR, NDI\params\VistaProperty, ParamDesc, 0, %Vista_Property%
+HKR, NDI\params\VistaProperty, type, 0, "edit"
+HKR, NDI\params\VistaProperty, LimitText, 0, "12"
+HKR, NDI\params\VistaProperty, UpperCase, 0, "1"
+HKR, NDI\params\VistaProperty, default, 0, " "
+HKR, NDI\params\VistaProperty, optional, 0, "1"
+
+; No sys copyfiles - the sys files are already in-build
+; (part of the operating system).
+; We do not support XP SP1-, 2003 SP1-, ME, 9x.
+
+[Strings]
+Linux = "Linux Developer Community"
+LinuxDevice = "Linux USB Ethernet/RNDIS Gadget"
+Vista_Property = "Optional Vista Property"
diff --git a/Documentation/usb/mass-storage.rst b/Documentation/usb/mass-storage.rst
new file mode 100644
index 000000000..d181b47c3
--- /dev/null
+++ b/Documentation/usb/mass-storage.rst
@@ -0,0 +1,234 @@
+=========================
+Mass Storage Gadget (MSG)
+=========================
+
+Overview
+========
+
+ Mass Storage Gadget (or MSG) acts as a USB Mass Storage device,
+ appearing to the host as a disk or a CD-ROM drive. It supports
+ multiple logical units (LUNs). Backing storage for each LUN is
+ provided by a regular file or a block device, access can be limited
+ to read-only, and gadget can indicate that it is removable and/or
+ CD-ROM (the latter implies read-only access).
+
+ Its requirements are modest; only a bulk-in and a bulk-out endpoint
+ are needed. The memory requirement amounts to two 16K buffers.
+ Support is included for full-speed, high-speed and SuperSpeed
+ operation.
+
+ Note that the driver is slightly non-portable in that it assumes
+ a single memory/DMA buffer will be usable for bulk-in and bulk-out
+ endpoints. With most device controllers this is not an issue, but
+ there may be some with hardware restrictions that prevent a buffer
+ from being used by more than one endpoint.
+
+ This document describes how to use the gadget from user space, its
+ relation to mass storage function (or MSF) and different gadgets
+ using it, and how it differs from File Storage Gadget (or FSG)
+ (which is no longer included in Linux). It will talk only briefly
+ about how to use MSF within composite gadgets.
+
+Module parameters
+=================
+
+ The mass storage gadget accepts the following mass storage specific
+ module parameters:
+
+ - file=filename[,filename...]
+
+ This parameter lists paths to files or block devices used for
+ backing storage for each logical unit. There may be at most
+ FSG_MAX_LUNS (8) LUNs set. If more files are specified, they will
+ be silently ignored. See also “luns” parameter.
+
+ *BEWARE* that if a file is used as a backing storage, it may not
+ be modified by any other process. This is because the host
+ assumes the data does not change without its knowledge. It may be
+ read, but (if the logical unit is writable) due to buffering on
+ the host side, the contents are not well defined.
+
+ The size of the logical unit will be rounded down to a full
+ logical block. The logical block size is 2048 bytes for LUNs
+ simulating CD-ROM, block size of the device if the backing file is
+ a block device, or 512 bytes otherwise.
+
+ - removable=b[,b...]
+
+ This parameter specifies whether each logical unit should be
+ removable. “b” here is either “y”, “Y” or “1” for true or “n”,
+ “N” or “0” for false.
+
+ If this option is set for a logical unit, gadget will accept an
+ “eject” SCSI request (Start/Stop Unit). When it is sent, the
+ backing file will be closed to simulate ejection and the logical
+ unit will not be mountable by the host until a new backing file is
+ specified by userspace on the device (see “sysfs entries”
+ section).
+
+ If a logical unit is not removable (the default), a backing file
+ must be specified for it with the “file” parameter as the module
+ is loaded. The same applies if the module is built in, no
+ exceptions.
+
+ The default value of the flag is false, *HOWEVER* it used to be
+ true. This has been changed to better match File Storage Gadget
+ and because it seems like a saner default after all. Thus to
+ maintain compatibility with older kernels, it's best to specify
+ the default values. Also, if one relied on old default, explicit
+ “n” needs to be specified now.
+
+ Note that “removable” means the logical unit's media can be
+ ejected or removed (as is true for a CD-ROM drive or a card
+ reader). It does *not* mean that the entire gadget can be
+ unplugged from the host; the proper term for that is
+ “hot-unpluggable”.
+
+ - cdrom=b[,b...]
+
+ This parameter specifies whether each logical unit should simulate
+ CD-ROM. The default is false.
+
+ - ro=b[,b...]
+
+ This parameter specifies whether each logical unit should be
+ reported as read only. This will prevent host from modifying the
+ backing files.
+
+ Note that if this flag for given logical unit is false but the
+ backing file could not be opened in read/write mode, the gadget
+ will fall back to read only mode anyway.
+
+ The default value for non-CD-ROM logical units is false; for
+ logical units simulating CD-ROM it is forced to true.
+
+ - nofua=b[,b...]
+
+ This parameter specifies whether FUA flag should be ignored in SCSI
+ Write10 and Write12 commands sent to given logical units.
+
+ MS Windows mounts removable storage in “Removal optimised mode” by
+ default. All the writes to the media are synchronous, which is
+ achieved by setting the FUA (Force Unit Access) bit in SCSI
+ Write(10,12) commands. This forces each write to wait until the
+ data has actually been written out and prevents I/O requests
+ aggregation in block layer dramatically decreasing performance.
+
+ Note that this may mean that if the device is powered from USB and
+ the user unplugs the device without unmounting it first (which at
+ least some Windows users do), the data may be lost.
+
+ The default value is false.
+
+ - luns=N
+
+ This parameter specifies number of logical units the gadget will
+ have. It is limited by FSG_MAX_LUNS (8) and higher value will be
+ capped.
+
+ If this parameter is provided, and the number of files specified
+ in “file” argument is greater then the value of “luns”, all excess
+ files will be ignored.
+
+ If this parameter is not present, the number of logical units will
+ be deduced from the number of files specified in the “file”
+ parameter. If the file parameter is missing as well, one is
+ assumed.
+
+ - stall=b
+
+ Specifies whether the gadget is allowed to halt bulk endpoints.
+ The default is determined according to the type of USB device
+ controller, but usually true.
+
+ In addition to the above, the gadget also accepts the following
+ parameters defined by the composite framework (they are common to
+ all composite gadgets so just a quick listing):
+
+ - idVendor -- USB Vendor ID (16 bit integer)
+ - idProduct -- USB Product ID (16 bit integer)
+ - bcdDevice -- USB Device version (BCD) (16 bit integer)
+ - iManufacturer -- USB Manufacturer string (string)
+ - iProduct -- USB Product string (string)
+ - iSerialNumber -- SerialNumber string (sting)
+
+sysfs entries
+=============
+
+ For each logical unit, the gadget creates a directory in the sysfs
+ hierarchy. Inside of it the following three files are created:
+
+ - file
+
+ When read it returns the path to the backing file for the given
+ logical unit. If there is no backing file (possible only if the
+ logical unit is removable), the content is empty.
+
+ When written into, it changes the backing file for given logical
+ unit. This change can be performed even if given logical unit is
+ not specified as removable (but that may look strange to the
+ host). It may fail, however, if host disallowed medium removal
+ with the Prevent-Allow Medium Removal SCSI command.
+
+ - ro
+
+ Reflects the state of ro flag for the given logical unit. It can
+ be read any time, and written to when there is no backing file
+ open for given logical unit.
+
+ - nofua
+
+ Reflects the state of nofua flag for given logical unit. It can
+ be read and written.
+
+ Other then those, as usual, the values of module parameters can be
+ read from /sys/module/g_mass_storage/parameters/* files.
+
+Other gadgets using mass storage function
+=========================================
+
+ The Mass Storage Gadget uses the Mass Storage Function to handle
+ mass storage protocol. As a composite function, MSF may be used by
+ other gadgets as well (eg. g_multi and acm_ms).
+
+ All of the information in previous sections are valid for other
+ gadgets using MSF, except that support for mass storage related
+ module parameters may be missing, or the parameters may have
+ a prefix. To figure out whether any of this is true one needs to
+ consult the gadget's documentation or its source code.
+
+ For examples of how to include mass storage function in gadgets, one
+ may take a look at mass_storage.c, acm_ms.c and multi.c (sorted by
+ complexity).
+
+Relation to file storage gadget
+===============================
+
+ The Mass Storage Function and thus the Mass Storage Gadget has been
+ based on the File Storage Gadget. The difference between the two is
+ that MSG is a composite gadget (ie. uses the composite framework)
+ while file storage gadget was a traditional gadget. From userspace
+ point of view this distinction does not really matter, but from
+ kernel hacker's point of view, this means that (i) MSG does not
+ duplicate code needed for handling basic USB protocol commands and
+ (ii) MSF can be used in any other composite gadget.
+
+ Because of that, File Storage Gadget has been removed in Linux 3.8.
+ All users need to transition to the Mass Storage Gadget. The two
+ gadgets behave mostly the same from the outside except:
+
+ 1. In FSG the “removable” and “cdrom” module parameters set the flag
+ for all logical units whereas in MSG they accept a list of y/n
+ values for each logical unit. If one uses only a single logical
+ unit this does not matter, but if there are more, the y/n value
+ needs to be repeated for each logical unit.
+
+ 2. FSG's “serial”, “vendor”, “product” and “release” module
+ parameters are handled in MSG by the composite layer's parameters
+ named respectively: “iSerialnumber”, “idVendor”, “idProduct” and
+ “bcdDevice”.
+
+ 3. MSG does not support FSG's test mode, thus “transport”,
+ “protocol” and “buflen” FSG's module parameters are not
+ supported. MSG always uses SCSI protocol with bulk only
+ transport mode and 16 KiB buffers.
diff --git a/Documentation/usb/misc_usbsevseg.rst b/Documentation/usb/misc_usbsevseg.rst
new file mode 100644
index 000000000..6274aee08
--- /dev/null
+++ b/Documentation/usb/misc_usbsevseg.rst
@@ -0,0 +1,51 @@
+=============================
+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/mtouchusb.rst b/Documentation/usb/mtouchusb.rst
new file mode 100644
index 000000000..d1111b74b
--- /dev/null
+++ b/Documentation/usb/mtouchusb.rst
@@ -0,0 +1,84 @@
+================
+mtouchusb driver
+================
+
+Changes
+=======
+
+- 0.3 - Created based off of scanner & INSTALL from the original touchscreen
+ driver on freecode (http://freecode.com/projects/3mtouchscreendriver)
+- Amended for linux-2.4.18, then 2.4.19
+
+- 0.5 - Complete rewrite using Linux Input in 2.6.3
+ Unfortunately no calibration support at this time
+
+- 1.4 - Multiple changes to support the EXII 5000UC and house cleaning
+ Changed reset from standard USB dev reset to vendor reset
+ Changed data sent to host from compensated to raw coordinates
+ Eliminated vendor/product module params
+ Performed multiple successful tests with an EXII-5010UC
+
+Supported Hardware
+==================
+
+::
+
+ All controllers have the Vendor: 0x0596 & Product: 0x0001
+
+
+ Controller Description Part Number
+ ------------------------------------------------------
+
+ USB Capacitive - Pearl Case 14-205 (Discontinued)
+ USB Capacitive - Black Case 14-124 (Discontinued)
+ USB Capacitive - No Case 14-206 (Discontinued)
+
+ USB Capacitive - Pearl Case EXII-5010UC
+ USB Capacitive - Black Case EXII-5030UC
+ USB Capacitive - No Case EXII-5050UC
+
+Driver Notes
+============
+
+Installation is simple, you only need to add Linux Input, Linux USB, and the
+driver to the kernel. The driver can also be optionally built as a module.
+
+This driver appears to be one of possible 2 Linux USB Input Touchscreen
+drivers. Although 3M produces a binary only driver available for
+download, I persist in updating this driver since I would like to use the
+touchscreen for embedded apps using QTEmbedded, DirectFB, etc. So I feel the
+logical choice is to use Linux Input.
+
+Currently there is no way to calibrate the device via this driver. Even if
+the device could be calibrated, the driver pulls to raw coordinate data from
+the controller. This means calibration must be performed within the
+userspace.
+
+The controller screen resolution is now 0 to 16384 for both X and Y reporting
+the raw touch data. This is the same for the old and new capacitive USB
+controllers.
+
+Perhaps at some point an abstract function will be placed into evdev so
+generic functions like calibrations, resets, and vendor information can be
+requested from the userspace (And the drivers would handle the vendor specific
+tasks).
+
+TODO
+====
+
+Implement a control urb again to handle requests to and from the device
+such as calibration, etc once/if it becomes available.
+
+Disclaimer
+==========
+
+I am not a MicroTouch/3M employee, nor have I ever been. 3M does not support
+this driver! If you want touch drivers only supported within X, please go to:
+
+http://www.3m.com/3MTouchSystems/
+
+Thanks
+======
+
+A huge thank you to 3M Touch Systems for the EXII-5010UC controllers for
+testing!
diff --git a/Documentation/usb/ohci.rst b/Documentation/usb/ohci.rst
new file mode 100644
index 000000000..bb3c49719
--- /dev/null
+++ b/Documentation/usb/ohci.rst
@@ -0,0 +1,35 @@
+====
+OHCI
+====
+
+23-Aug-2002
+
+The "ohci-hcd" driver is a USB Host Controller Driver (HCD) that is derived
+from the "usb-ohci" driver from the 2.4 kernel series. The "usb-ohci" code
+was written primarily by Roman Weissgaerber <weissg@vienna.at> but with
+contributions from many others (read its copyright/licencing header).
+
+It supports the "Open Host Controller Interface" (OHCI), which standardizes
+hardware register protocols used to talk to USB 1.1 host controllers. As
+compared to the earlier "Universal Host Controller Interface" (UHCI) from
+Intel, it pushes more intelligence into the hardware. USB 1.1 controllers
+from vendors other than Intel and VIA generally use OHCI.
+
+Changes since the 2.4 kernel include
+
+ - improved robustness; bugfixes; and less overhead
+ - supports the updated and simplified usbcore APIs
+ - interrupt transfers can be larger, and can be queued
+ - less code, by using the upper level "hcd" framework
+ - supports some non-PCI implementations of OHCI
+ - ... more
+
+The "ohci-hcd" driver handles all USB 1.1 transfer types. Transfers of all
+types can be queued. That was also true in "usb-ohci", except for interrupt
+transfers. Previously, using periods of one frame would risk data loss due
+to overhead in IRQ processing. When interrupt transfers are queued, those
+risks can be minimized by making sure the hardware always has transfers to
+work on while the OS is getting around to the relevant IRQ processing.
+
+- David Brownell
+ <dbrownell@users.sourceforge.net>
diff --git a/Documentation/usb/raw-gadget.rst b/Documentation/usb/raw-gadget.rst
new file mode 100644
index 000000000..68d879a80
--- /dev/null
+++ b/Documentation/usb/raw-gadget.rst
@@ -0,0 +1,84 @@
+==============
+USB Raw Gadget
+==============
+
+USB Raw Gadget is a kernel module that provides a userspace interface for
+the USB Gadget subsystem. Essentially it allows to emulate USB devices
+from userspace. Enabled with CONFIG_USB_RAW_GADGET. Raw Gadget is
+currently a strictly debugging feature and shouldn't be used in
+production, use GadgetFS instead.
+
+Comparison to GadgetFS
+~~~~~~~~~~~~~~~~~~~~~~
+
+Raw Gadget is similar to GadgetFS, but provides a more low-level and
+direct access to the USB Gadget layer for the userspace. The key
+differences are:
+
+1. Every USB request is passed to the userspace to get a response, while
+ GadgetFS responds to some USB requests internally based on the provided
+ descriptors. However note, that the UDC driver might respond to some
+ requests on its own and never forward them to the Gadget layer.
+
+2. GadgetFS performs some sanity checks on the provided USB descriptors,
+ while Raw Gadget allows you to provide arbitrary data as responses to
+ USB requests.
+
+3. Raw Gadget provides a way to select a UDC device/driver to bind to,
+ while GadgetFS currently binds to the first available UDC.
+
+4. Raw Gadget explicitly exposes information about endpoints addresses and
+ capabilities allowing a user to write UDC-agnostic gadgets.
+
+5. Raw Gadget has ioctl-based interface instead of a filesystem-based one.
+
+Userspace interface
+~~~~~~~~~~~~~~~~~~~
+
+To create a Raw Gadget instance open /dev/raw-gadget. Multiple raw-gadget
+instances (bound to different UDCs) can be used at the same time. The
+interaction with the opened file happens through the ioctl() calls, see
+comments in include/uapi/linux/usb/raw_gadget.h for details.
+
+The typical usage of Raw Gadget looks like:
+
+1. Open Raw Gadget instance via /dev/raw-gadget.
+2. Initialize the instance via USB_RAW_IOCTL_INIT.
+3. Launch the instance with USB_RAW_IOCTL_RUN.
+4. In a loop issue USB_RAW_IOCTL_EVENT_FETCH calls to receive events from
+ Raw Gadget and react to those depending on what kind of USB device
+ needs to be emulated.
+
+Note, that some UDC drivers have fixed addresses assigned to endpoints, and
+therefore arbitrary endpoint addresses can't be used in the descriptors.
+Nevertheles, Raw Gadget provides a UDC-agnostic way to write USB gadgets.
+Once a USB_RAW_EVENT_CONNECT event is received via USB_RAW_IOCTL_EVENT_FETCH,
+the USB_RAW_IOCTL_EPS_INFO ioctl can be used to find out information about
+endpoints that the UDC driver has. Based on that information, the user must
+chose UDC endpoints that will be used for the gadget being emulated, and
+properly assign addresses in endpoint descriptors.
+
+You can find usage examples (along with a test suite) here:
+
+https://github.com/xairy/raw-gadget
+
+Internal details
+~~~~~~~~~~~~~~~~
+
+Currently every endpoint read/write ioctl submits a USB request and waits until
+its completion. This is the desired mode for coverage-guided fuzzing (as we'd
+like all USB request processing happen during the lifetime of a syscall),
+and must be kept in the implementation. (This might be slow for real world
+applications, thus the O_NONBLOCK improvement suggestion below.)
+
+Potential future improvements
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+- Report more events (suspend, resume, etc.) through USB_RAW_IOCTL_EVENT_FETCH.
+
+- Support O_NONBLOCK I/O.
+
+- Support USB 3 features (accept SS endpoint companion descriptor when
+ enabling endpoints; allow providing stream_id for bulk transfers).
+
+- Support ISO transfer features (expose frame_number for completed requests).
diff --git a/Documentation/usb/text_files.rst b/Documentation/usb/text_files.rst
new file mode 100644
index 000000000..1c18c05c3
--- /dev/null
+++ b/Documentation/usb/text_files.rst
@@ -0,0 +1,23 @@
+Linux CDC ACM inf
+-----------------
+
+.. include:: linux-cdc-acm.inf
+ :literal:
+
+Linux inf
+---------
+
+.. include:: linux.inf
+ :literal:
+
+USB devfs drop permissions source
+---------------------------------
+
+.. literalinclude:: usbdevfs-drop-permissions.c
+ :language: c
+
+Credits
+-------
+
+.. include:: CREDITS
+ :literal:
diff --git a/Documentation/usb/usb-help.rst b/Documentation/usb/usb-help.rst
new file mode 100644
index 000000000..dc23ecd4d
--- /dev/null
+++ b/Documentation/usb/usb-help.rst
@@ -0,0 +1,17 @@
+==============
+USB references
+==============
+
+2008-Mar-7
+
+For USB help other than the readme files that are located in
+`Documentation/usb/*`, see the following:
+
+- Linux-USB project: http://www.linux-usb.org
+ mirrors at http://usb.in.tum.de/linux-usb/
+ and http://it.linux-usb.org
+- Linux USB Guide: http://linux-usb.sourceforge.net
+- Linux-USB device overview (working devices and drivers):
+ http://www.qbik.ch/usb/devices/
+
+The Linux-USB mailing list is at linux-usb@vger.kernel.org
diff --git a/Documentation/usb/usb-serial.rst b/Documentation/usb/usb-serial.rst
new file mode 100644
index 000000000..8fa7dbd3d
--- /dev/null
+++ b/Documentation/usb/usb-serial.rst
@@ -0,0 +1,537 @@
+==========
+USB serial
+==========
+
+Introduction
+============
+
+ The USB serial driver currently supports a number of different USB to
+ serial converter products, as well as some devices that use a serial
+ interface from userspace to talk to the device.
+
+ See the individual product section below for specific information about
+ the different devices.
+
+
+Configuration
+=============
+
+ Currently the driver can handle up to 256 different serial interfaces at
+ one time.
+
+ The major number that the driver uses is 188 so to use the driver,
+ create the following nodes::
+
+ mknod /dev/ttyUSB0 c 188 0
+ mknod /dev/ttyUSB1 c 188 1
+ mknod /dev/ttyUSB2 c 188 2
+ mknod /dev/ttyUSB3 c 188 3
+ .
+ .
+ .
+ mknod /dev/ttyUSB254 c 188 254
+ mknod /dev/ttyUSB255 c 188 255
+
+ When the device is connected and recognized by the driver, the driver
+ will print to the system log, which node(s) the device has been bound
+ to.
+
+
+Specific Devices Supported
+==========================
+
+
+ConnectTech WhiteHEAT 4 port converter
+--------------------------------------
+
+ ConnectTech has been very forthcoming with information about their
+ device, including providing a unit to test with.
+
+ The driver is officially supported by Connect Tech Inc.
+ http://www.connecttech.com
+
+ For any questions or problems with this driver, please contact
+ Connect Tech's Support Department at support@connecttech.com
+
+
+HandSpring Visor, Palm USB, and Clié USB driver
+-----------------------------------------------
+
+ This driver works with all HandSpring USB, Palm USB, and Sony Clié USB
+ devices.
+
+ Only when the device tries to connect to the host, will the device show
+ up to the host as a valid USB device. When this happens, the device is
+ properly enumerated, assigned a port, and then communication _should_ be
+ possible. The driver cleans up properly when the device is removed, or
+ the connection is canceled on the device.
+
+ NOTE:
+ This means that in order to talk to the device, the sync button must be
+ pressed BEFORE trying to get any program to communicate to the device.
+ This goes against the current documentation for pilot-xfer and other
+ packages, but is the only way that it will work due to the hardware
+ in the device.
+
+ When the device is connected, try talking to it on the second port
+ (this is usually /dev/ttyUSB1 if you do not have any other usb-serial
+ devices in the system.) The system log should tell you which port is
+ the port to use for the HotSync transfer. The "Generic" port can be used
+ for other device communication, such as a PPP link.
+
+ For some Sony Clié devices, /dev/ttyUSB0 must be used to talk to the
+ device. This is true for all OS version 3.5 devices, and most devices
+ that have had a flash upgrade to a newer version of the OS. See the
+ kernel system log for information on which is the correct port to use.
+
+ If after pressing the sync button, nothing shows up in the system log,
+ try resetting the device, first a hot reset, and then a cold reset if
+ necessary. Some devices need this before they can talk to the USB port
+ properly.
+
+ Devices that are not compiled into the kernel can be specified with module
+ parameters. e.g. modprobe visor vendor=0x54c product=0x66
+
+ There is a webpage and mailing lists for this portion of the driver at:
+ http://sourceforge.net/projects/usbvisor/
+
+ For any questions or problems with this driver, please contact Greg
+ Kroah-Hartman at greg@kroah.com
+
+
+PocketPC PDA Driver
+-------------------
+
+ This driver can be used to connect to Compaq iPAQ, HP Jornada, Casio EM500
+ and other PDAs running Windows CE 3.0 or PocketPC 2002 using a USB
+ cable/cradle.
+ Most devices supported by ActiveSync are supported out of the box.
+ For others, please use module parameters to specify the product and vendor
+ id. e.g. modprobe ipaq vendor=0x3f0 product=0x1125
+
+ The driver presents a serial interface (usually on /dev/ttyUSB0) over
+ which one may run ppp and establish a TCP/IP link to the PDA. Once this
+ is done, you can transfer files, backup, download email etc. The most
+ significant advantage of using USB is speed - I can get 73 to 113
+ kbytes/sec for download/upload to my iPAQ.
+
+ This driver is only one of a set of components required to utilize
+ the USB connection. Please visit http://synce.sourceforge.net which
+ contains the necessary packages and a simple step-by-step howto.
+
+ Once connected, you can use Win CE programs like ftpView, Pocket Outlook
+ from the PDA and xcerdisp, synce utilities from the Linux side.
+
+ To use Pocket IE, follow the instructions given at
+ http://www.tekguru.co.uk/EM500/usbtonet.htm to achieve the same thing
+ on Win98. Omit the proxy server part; Linux is quite capable of forwarding
+ packets unlike Win98. Another modification is required at least for the
+ iPAQ - disable autosync by going to the Start/Settings/Connections menu
+ and unchecking the "Automatically synchronize ..." box. Go to
+ Start/Programs/Connections, connect the cable and select "usbdial" (or
+ whatever you named your new USB connection). You should finally wind
+ up with a "Connected to usbdial" window with status shown as connected.
+ Now start up PIE and browse away.
+
+ If it doesn't work for some reason, load both the usbserial and ipaq module
+ with the module parameter "debug" set to 1 and examine the system log.
+ You can also try soft-resetting your PDA before attempting a connection.
+
+ Other functionality may be possible depending on your PDA. According to
+ Wes Cilldhaire <billybobjoehenrybob@hotmail.com>, with the Toshiba E570,
+ ...if you boot into the bootloader (hold down the power when hitting the
+ reset button, continuing to hold onto the power until the bootloader screen
+ is displayed), then put it in the cradle with the ipaq driver loaded, open
+ a terminal on /dev/ttyUSB0, it gives you a "USB Reflash" terminal, which can
+ be used to flash the ROM, as well as the microP code.. so much for needing
+ Toshiba's $350 serial cable for flashing!! :D
+ NOTE: This has NOT been tested. Use at your own risk.
+
+ For any questions or problems with the driver, please contact Ganesh
+ Varadarajan <ganesh@veritas.com>
+
+
+Keyspan PDA Serial Adapter
+--------------------------
+
+ Single port DB-9 serial adapter, pushed as a PDA adapter for iMacs (mostly
+ sold in Macintosh catalogs, comes in a translucent white/green dongle).
+ Fairly simple device. Firmware is homebrew.
+ This driver also works for the Xircom/Entrega single port serial adapter.
+
+ Current status:
+
+ Things that work:
+ - basic input/output (tested with 'cu')
+ - blocking write when serial line can't keep up
+ - changing baud rates (up to 115200)
+ - getting/setting modem control pins (TIOCM{GET,SET,BIS,BIC})
+ - sending break (although duration looks suspect)
+
+ Things that don't:
+ - device strings (as logged by kernel) have trailing binary garbage
+ - device ID isn't right, might collide with other Keyspan products
+ - changing baud rates ought to flush tx/rx to avoid mangled half characters
+
+ Big Things on the todo list:
+ - parity, 7 vs 8 bits per char, 1 or 2 stop bits
+ - HW flow control
+ - not all of the standard USB descriptors are handled:
+ Get_Status, Set_Feature, O_NONBLOCK, select()
+
+ For any questions or problems with this driver, please contact Brian
+ Warner at warner@lothar.com
+
+
+Keyspan USA-series Serial Adapters
+----------------------------------
+
+ Single, Dual and Quad port adapters - driver uses Keyspan supplied
+ firmware and is being developed with their support.
+
+ Current status:
+
+ The USA-18X, USA-28X, USA-19, USA-19W and USA-49W are supported and
+ have been pretty thoroughly tested at various baud rates with 8-N-1
+ character settings. Other character lengths and parity setups are
+ presently untested.
+
+ The USA-28 isn't yet supported though doing so should be pretty
+ straightforward. Contact the maintainer if you require this
+ functionality.
+
+ More information is available at:
+
+ http://www.carnationsoftware.com/carnation/Keyspan.html
+
+ For any questions or problems with this driver, please contact Hugh
+ Blemings at hugh@misc.nu
+
+
+FTDI Single Port Serial Driver
+------------------------------
+
+ This is a single port DB-25 serial adapter.
+
+ Devices supported include:
+
+ - TripNav TN-200 USB GPS
+ - Navis Engineering Bureau CH-4711 USB GPS
+
+ For any questions or problems with this driver, please contact Bill Ryder.
+
+
+ZyXEL omni.net lcd plus ISDN TA
+-------------------------------
+
+ This is an ISDN TA. Please report both successes and troubles to
+ azummo@towertech.it
+
+
+Cypress M8 CY4601 Family Serial Driver
+--------------------------------------
+
+ This driver was in most part developed by Neil "koyama" Whelchel. It
+ has been improved since that previous form to support dynamic serial
+ line settings and improved line handling. The driver is for the most
+ part stable and has been tested on an smp machine. (dual p2)
+
+ Chipsets supported under CY4601 family:
+
+ CY7C63723, CY7C63742, CY7C63743, CY7C64013
+
+ Devices supported:
+
+ - DeLorme's USB Earthmate GPS (SiRF Star II lp arch)
+ - Cypress HID->COM RS232 adapter
+
+ Note:
+ Cypress Semiconductor claims no affiliation with the
+ hid->com device.
+
+ Most devices using chipsets under the CY4601 family should
+ work with the driver. As long as they stay true to the CY4601
+ usbserial specification.
+
+ Technical notes:
+
+ The Earthmate starts out at 4800 8N1 by default... the driver will
+ upon start init to this setting. usbserial core provides the rest
+ of the termios settings, along with some custom termios so that the
+ output is in proper format and parsable.
+
+ The device can be put into sirf mode by issuing NMEA command::
+
+ $PSRF100,<protocol>,<baud>,<databits>,<stopbits>,<parity>*CHECKSUM
+ $PSRF100,0,9600,8,1,0*0C
+
+ It should then be sufficient to change the port termios to match this
+ to begin communicating.
+
+ As far as I can tell it supports pretty much every sirf command as
+ documented online available with firmware 2.31, with some unknown
+ message ids.
+
+ The hid->com adapter can run at a maximum baud of 115200bps. Please note
+ that the device has trouble or is incapable of raising line voltage properly.
+ It will be fine with null modem links, as long as you do not try to link two
+ together without hacking the adapter to set the line high.
+
+ The driver is smp safe. Performance with the driver is rather low when using
+ it for transferring files. This is being worked on, but I would be willing to
+ accept patches. An urb queue or packet buffer would likely fit the bill here.
+
+ If you have any questions, problems, patches, feature requests, etc. you can
+ contact me here via email:
+
+ dignome@gmail.com
+
+ (your problems/patches can alternately be submitted to usb-devel)
+
+
+Digi AccelePort Driver
+----------------------
+
+ This driver supports the Digi AccelePort USB 2 and 4 devices, 2 port
+ (plus a parallel port) and 4 port USB serial converters. The driver
+ does NOT yet support the Digi AccelePort USB 8.
+
+ This driver works under SMP with the usb-uhci driver. It does not
+ work under SMP with the uhci driver.
+
+ The driver is generally working, though we still have a few more ioctls
+ to implement and final testing and debugging to do. The parallel port
+ on the USB 2 is supported as a serial to parallel converter; in other
+ words, it appears as another USB serial port on Linux, even though
+ physically it is really a parallel port. The Digi Acceleport USB 8
+ is not yet supported.
+
+ Please contact Peter Berger (pberger@brimson.com) or Al Borchers
+ (alborchers@steinerpoint.com) for questions or problems with this
+ driver.
+
+
+Belkin USB Serial Adapter F5U103
+--------------------------------
+
+ Single port DB-9/PS-2 serial adapter from Belkin with firmware by eTEK Labs.
+ The Peracom single port serial adapter also works with this driver, as
+ well as the GoHubs adapter.
+
+ Current status:
+
+ The following have been tested and work:
+
+ - Baud rate 300-230400
+ - Data bits 5-8
+ - Stop bits 1-2
+ - Parity N,E,O,M,S
+ - Handshake None, Software (XON/XOFF), Hardware (CTSRTS,CTSDTR) [1]_
+ - Break Set and clear
+ - Line control Input/Output query and control [2]_
+
+ .. [1]
+ Hardware input flow control is only enabled for firmware
+ levels above 2.06. Read source code comments describing Belkin
+ firmware errata. Hardware output flow control is working for all
+ firmware versions.
+
+ .. [2]
+ Queries of inputs (CTS,DSR,CD,RI) show the last
+ reported state. Queries of outputs (DTR,RTS) show the last
+ requested state and may not reflect current state as set by
+ automatic hardware flow control.
+
+ TO DO List:
+ - Add true modem control line query capability. Currently tracks the
+ states reported by the interrupt and the states requested.
+ - Add error reporting back to application for UART error conditions.
+ - Add support for flush ioctls.
+ - Add everything else that is missing :)
+
+ For any questions or problems with this driver, please contact William
+ Greathouse at wgreathouse@smva.com
+
+
+Empeg empeg-car Mark I/II Driver
+--------------------------------
+
+ This is an experimental driver to provide connectivity support for the
+ client synchronization tools for an Empeg empeg-car mp3 player.
+
+ Tips:
+ * Don't forget to create the device nodes for ttyUSB{0,1,2,...}
+ * modprobe empeg (modprobe is your friend)
+ * emptool --usb /dev/ttyUSB0 (or whatever you named your device node)
+
+ For any questions or problems with this driver, please contact Gary
+ Brubaker at xavyer@ix.netcom.com
+
+
+MCT USB Single Port Serial Adapter U232
+---------------------------------------
+
+ This driver is for the MCT USB-RS232 Converter (25 pin, Model No.
+ U232-P25) from Magic Control Technology Corp. (there is also a 9 pin
+ Model No. U232-P9). More information about this device can be found at
+ the manufacturer's web-site: http://www.mct.com.tw.
+
+ The driver is generally working, though it still needs some more testing.
+ It is derived from the Belkin USB Serial Adapter F5U103 driver and its
+ TODO list is valid for this driver as well.
+
+ This driver has also been found to work for other products, which have
+ the same Vendor ID but different Product IDs. Sitecom's U232-P25 serial
+ converter uses Product ID 0x230 and Vendor ID 0x711 and works with this
+ driver. Also, D-Link's DU-H3SP USB BAY also works with this driver.
+
+ For any questions or problems with this driver, please contact Wolfgang
+ Grandegger at wolfgang@ces.ch
+
+
+Inside Out Networks Edgeport Driver
+-----------------------------------
+
+ This driver supports all devices made by Inside Out Networks, specifically
+ the following models:
+
+ - Edgeport/4
+ - Rapidport/4
+ - Edgeport/4t
+ - Edgeport/2
+ - Edgeport/4i
+ - Edgeport/2i
+ - Edgeport/421
+ - Edgeport/21
+ - Edgeport/8
+ - Edgeport/8 Dual
+ - Edgeport/2D8
+ - Edgeport/4D8
+ - Edgeport/8i
+ - Edgeport/2 DIN
+ - Edgeport/4 DIN
+ - Edgeport/16 Dual
+
+ For any questions or problems with this driver, please contact Greg
+ Kroah-Hartman at greg@kroah.com
+
+
+REINER SCT cyberJack pinpad/e-com USB chipcard reader
+-----------------------------------------------------
+
+ Interface to ISO 7816 compatible contactbased chipcards, e.g. GSM SIMs.
+
+ Current status:
+
+ This is the kernel part of the driver for this USB card reader.
+ There is also a user part for a CT-API driver available. A site
+ for downloading is TBA. For now, you can request it from the
+ maintainer (linux-usb@sii.li).
+
+ For any questions or problems with this driver, please contact
+ linux-usb@sii.li
+
+
+Prolific PL2303 Driver
+----------------------
+
+ This driver supports any device that has the PL2303 chip from Prolific
+ in it. This includes a number of single port USB to serial converters,
+ more than 70% of USB GPS devices (in 2010), and some USB UPSes. Devices
+ from Aten (the UC-232) and IO-Data work with this driver, as does
+ the DCU-11 mobile-phone cable.
+
+ For any questions or problems with this driver, please contact Greg
+ Kroah-Hartman at greg@kroah.com
+
+
+KL5KUSB105 chipset / PalmConnect USB single-port adapter
+--------------------------------------------------------
+
+Current status:
+
+ The driver was put together by looking at the usb bus transactions
+ done by Palm's driver under Windows, so a lot of functionality is
+ still missing. Notably, serial ioctls are sometimes faked or not yet
+ implemented. Support for finding out about DSR and CTS line status is
+ however implemented (though not nicely), so your favorite autopilot(1)
+ and pilot-manager -daemon calls will work. Baud rates up to 115200
+ are supported, but handshaking (software or hardware) is not, which is
+ why it is wise to cut down on the rate used is wise for large
+ transfers until this is settled.
+
+ See http://www.uuhaus.de/linux/palmconnect.html for up-to-date
+ information on this driver.
+
+Winchiphead CH341 Driver
+------------------------
+
+ This driver is for the Winchiphead CH341 USB-RS232 Converter. This chip
+ also implements an IEEE 1284 parallel port, I2C and SPI, but that is not
+ supported by the driver. The protocol was analyzed from the behaviour
+ of the Windows driver, no datasheet is available at present.
+
+ The manufacturer's website: http://www.winchiphead.com/.
+
+ For any questions or problems with this driver, please contact
+ frank@kingswood-consulting.co.uk.
+
+Moschip MCS7720, MCS7715 driver
+-------------------------------
+
+ These chips are present in devices sold by various manufacturers, such as Syba
+ and Cables Unlimited. There may be others. The 7720 provides two serial
+ ports, and the 7715 provides one serial and one standard PC parallel port.
+ Support for the 7715's parallel port is enabled by a separate option, which
+ will not appear unless parallel port support is first enabled at the top-level
+ of the Device Drivers config menu. Currently only compatibility mode is
+ supported on the parallel port (no ECP/EPP).
+
+ TODO:
+ - Implement ECP/EPP modes for the parallel port.
+ - Baud rates higher than 115200 are currently broken.
+ - Devices with a single serial port based on the Moschip MCS7703 may work
+ with this driver with a simple addition to the usb_device_id table. I
+ don't have one of these devices, so I can't say for sure.
+
+Generic Serial driver
+---------------------
+
+ If your device is not one of the above listed devices, compatible with
+ the above models, you can try out the "generic" interface. This
+ interface does not provide any type of control messages sent to the
+ device, and does not support any kind of device flow control. All that
+ is required of your device is that it has at least one bulk in endpoint,
+ or one bulk out endpoint.
+
+ To enable the generic driver to recognize your device, provide::
+
+ echo <vid> <pid> >/sys/bus/usb-serial/drivers/generic/new_id
+
+ where the <vid> and <pid> is replaced with the hex representation of your
+ device's vendor id and product id.
+ If the driver is compiled as a module you can also provide one id when
+ loading the module::
+
+ insmod usbserial vendor=0x#### product=0x####
+
+ This driver has been successfully used to connect to the NetChip USB
+ development board, providing a way to develop USB firmware without
+ having to write a custom driver.
+
+ For any questions or problems with this driver, please contact Greg
+ Kroah-Hartman at greg@kroah.com
+
+
+Contact
+=======
+
+ If anyone has any problems using these drivers, with any of the above
+ specified products, please contact the specific driver's author listed
+ above, or join the Linux-USB mailing list (information on joining the
+ mailing list, as well as a link to its searchable archive is at
+ http://www.linux-usb.org/ )
+
+
+Greg Kroah-Hartman
+greg@kroah.com
diff --git a/Documentation/usb/usbdevfs-drop-permissions.c b/Documentation/usb/usbdevfs-drop-permissions.c
new file mode 100644
index 000000000..6b8da6ef0
--- /dev/null
+++ b/Documentation/usb/usbdevfs-drop-permissions.c
@@ -0,0 +1,120 @@
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <inttypes.h>
+#include <unistd.h>
+
+#include <linux/usbdevice_fs.h>
+
+/* For building without an updated set of headers */
+#ifndef USBDEVFS_DROP_PRIVILEGES
+#define USBDEVFS_DROP_PRIVILEGES _IOW('U', 30, __u32)
+#define USBDEVFS_CAP_DROP_PRIVILEGES 0x40
+#endif
+
+void drop_privileges(int fd, uint32_t mask)
+{
+ int res;
+
+ res = ioctl(fd, USBDEVFS_DROP_PRIVILEGES, &mask);
+ if (res)
+ printf("ERROR: USBDEVFS_DROP_PRIVILEGES returned %d\n", res);
+ else
+ printf("OK: privileges dropped!\n");
+}
+
+void reset_device(int fd)
+{
+ int res;
+
+ res = ioctl(fd, USBDEVFS_RESET);
+ if (!res)
+ printf("OK: USBDEVFS_RESET succeeded\n");
+ else
+ printf("ERROR: reset failed! (%d - %s)\n",
+ -res, strerror(-res));
+}
+
+void claim_some_intf(int fd)
+{
+ int i, res;
+
+ for (i = 0; i < 4; i++) {
+ res = ioctl(fd, USBDEVFS_CLAIMINTERFACE, &i);
+ if (!res)
+ printf("OK: claimed if %d\n", i);
+ else
+ printf("ERROR claiming if %d (%d - %s)\n",
+ i, -res, strerror(-res));
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ uint32_t mask, caps;
+ int c, fd;
+
+ fd = open(argv[1], O_RDWR);
+ if (fd < 0) {
+ printf("Failed to open file\n");
+ goto err_fd;
+ }
+
+ /*
+ * check if dropping privileges is supported,
+ * bail on systems where the capability is not present
+ */
+ ioctl(fd, USBDEVFS_GET_CAPABILITIES, &caps);
+ if (!(caps & USBDEVFS_CAP_DROP_PRIVILEGES)) {
+ printf("DROP_PRIVILEGES not supported\n");
+ goto err;
+ }
+
+ /*
+ * Drop privileges but keep the ability to claim all
+ * free interfaces (i.e., those not used by kernel drivers)
+ */
+ drop_privileges(fd, -1U);
+
+ printf("Available options:\n"
+ "[0] Exit now\n"
+ "[1] Reset device. Should fail if device is in use\n"
+ "[2] Claim 4 interfaces. Should succeed where not in use\n"
+ "[3] Narrow interface permission mask\n"
+ "Which option shall I run?: ");
+
+ while (scanf("%d", &c) == 1) {
+ switch (c) {
+ case 0:
+ goto exit;
+ case 1:
+ reset_device(fd);
+ break;
+ case 2:
+ claim_some_intf(fd);
+ break;
+ case 3:
+ printf("Insert new mask: ");
+ scanf("%x", &mask);
+ drop_privileges(fd, mask);
+ break;
+ default:
+ printf("I don't recognize that\n");
+ }
+
+ printf("Which test shall I run next?: ");
+ }
+
+exit:
+ close(fd);
+ return 0;
+
+err:
+ close(fd);
+err_fd:
+ return 1;
+}
diff --git a/Documentation/usb/usbip_protocol.rst b/Documentation/usb/usbip_protocol.rst
new file mode 100644
index 000000000..988c83216
--- /dev/null
+++ b/Documentation/usb/usbip_protocol.rst
@@ -0,0 +1,411 @@
+===============
+USB/IP protocol
+===============
+
+PRELIMINARY DRAFT, MAY CONTAIN MISTAKES!
+28 Jun 2011
+
+The USB/IP protocol follows a server/client architecture. The server exports the
+USB devices and the clients imports them. The device driver for the exported
+USB device runs on the client machine.
+
+The client may ask for the list of the exported USB devices. To get the list the
+client opens a TCP/IP connection towards the server, and sends an OP_REQ_DEVLIST
+packet on top of the TCP/IP connection (so the actual OP_REQ_DEVLIST may be sent
+in one or more pieces at the low level transport layer). The server sends back
+the OP_REP_DEVLIST packet which lists the exported USB devices. Finally the
+TCP/IP connection is closed.
+
+::
+
+ virtual host controller usb host
+ "client" "server"
+ (imports USB devices) (exports USB devices)
+ | |
+ | OP_REQ_DEVLIST |
+ | ----------------------------------------------> |
+ | |
+ | OP_REP_DEVLIST |
+ | <---------------------------------------------- |
+ | |
+
+Once the client knows the list of exported USB devices it may decide to use one
+of them. First the client opens a TCP/IP connection towards the server and
+sends an OP_REQ_IMPORT packet. The server replies with OP_REP_IMPORT. If the
+import was successful the TCP/IP connection remains open and will be used
+to transfer the URB traffic between the client and the server. The client may
+send two types of packets: the USBIP_CMD_SUBMIT to submit an URB, and
+USBIP_CMD_UNLINK to unlink a previously submitted URB. The answers of the
+server may be USBIP_RET_SUBMIT and USBIP_RET_UNLINK respectively.
+
+::
+
+ virtual host controller usb host
+ "client" "server"
+ (imports USB devices) (exports USB devices)
+ | |
+ | OP_REQ_IMPORT |
+ | ----------------------------------------------> |
+ | |
+ | OP_REP_IMPORT |
+ | <---------------------------------------------- |
+ | |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = n) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_RET_SUBMIT(seqnum = n) |
+ | <---------------------------------------------- |
+ | . |
+ | : |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = m) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = m+1) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = m+2) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_RET_SUBMIT(seqnum = m) |
+ | <---------------------------------------------- |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = m+3) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_RET_SUBMIT(seqnum = m+1) |
+ | <---------------------------------------------- |
+ | |
+ | USBIP_CMD_SUBMIT(seqnum = m+4) |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_RET_SUBMIT(seqnum = m+2) |
+ | <---------------------------------------------- |
+ | . |
+ | : |
+ | |
+ | USBIP_CMD_UNLINK |
+ | ----------------------------------------------> |
+ | |
+ | USBIP_RET_UNLINK |
+ | <---------------------------------------------- |
+ | |
+
+The fields are in network (big endian) byte order meaning that the most significant
+byte (MSB) is stored at the lowest address.
+
+
+OP_REQ_DEVLIST:
+ Retrieve the list of exported USB devices.
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0 |
++-----------+--------+------------+---------------------------------------------------+
+| 2 | 2 | 0x8005 | Command code: Retrieve the list of exported USB |
+| | | | devices. |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | 0x00000000 | Status: unused, shall be set to 0 |
++-----------+--------+------------+---------------------------------------------------+
+
+OP_REP_DEVLIST:
+ Reply with the list of exported USB devices.
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0.|
++-----------+--------+------------+---------------------------------------------------+
+| 2 | 2 | 0x0005 | Reply code: The list of exported USB devices. |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | 0x00000000 | Status: 0 for OK |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 4 | n | Number of exported devices: 0 means no exported |
+| | | | devices. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x0C | | | From now on the exported n devices are described, |
+| | | | if any. If no devices are exported the message |
+| | | | ends with the previous "number of exported |
+| | | | devices" field. |
++-----------+--------+------------+---------------------------------------------------+
+| | 256 | | path: Path of the device on the host exporting the|
+| | | | USB device, string closed with zero byte, e.g. |
+| | | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2" |
+| | | | The unused bytes shall be filled with zero |
+| | | | bytes. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x10C | 32 | | busid: Bus ID of the exported device, string |
+| | | | closed with zero byte, e.g. "3-2". The unused |
+| | | | bytes shall be filled with zero bytes. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x12C | 4 | | busnum |
++-----------+--------+------------+---------------------------------------------------+
+| 0x130 | 4 | | devnum |
++-----------+--------+------------+---------------------------------------------------+
+| 0x134 | 4 | | speed |
++-----------+--------+------------+---------------------------------------------------+
+| 0x138 | 2 | | idVendor |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13A | 2 | | idProduct |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13C | 2 | | bcdDevice |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13E | 1 | | bDeviceClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13F | 1 | | bDeviceSubClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x140 | 1 | | bDeviceProtocol |
++-----------+--------+------------+---------------------------------------------------+
+| 0x141 | 1 | | bConfigurationValue |
++-----------+--------+------------+---------------------------------------------------+
+| 0x142 | 1 | | bNumConfigurations |
++-----------+--------+------------+---------------------------------------------------+
+| 0x143 | 1 | | bNumInterfaces |
++-----------+--------+------------+---------------------------------------------------+
+| 0x144 | | m_0 | From now on each interface is described, all |
+| | | | together bNumInterfaces times, with the |
+| | | | the following 4 fields: |
++-----------+--------+------------+---------------------------------------------------+
+| | 1 | | bInterfaceClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x145 | 1 | | bInterfaceSubClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x146 | 1 | | bInterfaceProtocol |
++-----------+--------+------------+---------------------------------------------------+
+| 0x147 | 1 | | padding byte for alignment, shall be set to zero |
++-----------+--------+------------+---------------------------------------------------+
+| 0xC + | | | The second exported USB device starts at i=1 |
+| i*0x138 + | | | with the busid field. |
+| m_(i-1)*4 | | | |
++-----------+--------+------------+---------------------------------------------------+
+
+OP_REQ_IMPORT:
+ Request to import (attach) a remote USB device.
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0 |
++-----------+--------+------------+---------------------------------------------------+
+| 2 | 2 | 0x8003 | Command code: import a remote USB device. |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | 0x00000000 | Status: unused, shall be set to 0 |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 32 | | busid: the busid of the exported device on the |
+| | | | remote host. The possible values are taken |
+| | | | from the message field OP_REP_DEVLIST.busid. |
+| | | | A string closed with zero, the unused bytes |
+| | | | shall be filled with zeros. |
++-----------+--------+------------+---------------------------------------------------+
+
+OP_REP_IMPORT:
+ Reply to import (attach) a remote USB device.
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0 |
++-----------+--------+------------+---------------------------------------------------+
+| 2 | 2 | 0x0003 | Reply code: Reply to import. |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | 0x00000000 | Status: |
+| | | | |
+| | | | - 0 for OK |
+| | | | - 1 for error |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | | | From now on comes the details of the imported |
+| | | | device, if the previous status field was OK (0), |
+| | | | otherwise the reply ends with the status field. |
++-----------+--------+------------+---------------------------------------------------+
+| | 256 | | path: Path of the device on the host exporting the|
+| | | | USB device, string closed with zero byte, e.g. |
+| | | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2" |
+| | | | The unused bytes shall be filled with zero |
+| | | | bytes. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x108 | 32 | | busid: Bus ID of the exported device, string |
+| | | | closed with zero byte, e.g. "3-2". The unused |
+| | | | bytes shall be filled with zero bytes. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x128 | 4 | | busnum |
++-----------+--------+------------+---------------------------------------------------+
+| 0x12C | 4 | | devnum |
++-----------+--------+------------+---------------------------------------------------+
+| 0x130 | 4 | | speed |
++-----------+--------+------------+---------------------------------------------------+
+| 0x134 | 2 | | idVendor |
++-----------+--------+------------+---------------------------------------------------+
+| 0x136 | 2 | | idProduct |
++-----------+--------+------------+---------------------------------------------------+
+| 0x138 | 2 | | bcdDevice |
++-----------+--------+------------+---------------------------------------------------+
+| 0x139 | 1 | | bDeviceClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13A | 1 | | bDeviceSubClass |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13B | 1 | | bDeviceProtocol |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13C | 1 | | bConfigurationValue |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13D | 1 | | bNumConfigurations |
++-----------+--------+------------+---------------------------------------------------+
+| 0x13E | 1 | | bNumInterfaces |
++-----------+--------+------------+---------------------------------------------------+
+
+USBIP_CMD_SUBMIT:
+ Submit an URB
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 4 | 0x00000001 | command: Submit an URB |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | | seqnum: the sequence number of the URB to submit |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 4 | | devid |
++-----------+--------+------------+---------------------------------------------------+
+| 0xC | 4 | | direction: |
+| | | | |
+| | | | - 0: USBIP_DIR_OUT |
+| | | | - 1: USBIP_DIR_IN |
++-----------+--------+------------+---------------------------------------------------+
+| 0x10 | 4 | | ep: endpoint number, possible values are: 0...15 |
++-----------+--------+------------+---------------------------------------------------+
+| 0x14 | 4 | | transfer_flags: possible values depend on the |
+| | | | URB transfer type, see below |
++-----------+--------+------------+---------------------------------------------------+
+| 0x18 | 4 | | transfer_buffer_length |
++-----------+--------+------------+---------------------------------------------------+
+| 0x1C | 4 | | start_frame: specify the selected frame to |
+| | | | transmit an ISO frame, ignored if URB_ISO_ASAP |
+| | | | is specified at transfer_flags |
++-----------+--------+------------+---------------------------------------------------+
+| 0x20 | 4 | | number_of_packets: number of ISO packets |
++-----------+--------+------------+---------------------------------------------------+
+| 0x24 | 4 | | interval: maximum time for the request on the |
+| | | | server-side host controller |
++-----------+--------+------------+---------------------------------------------------+
+| 0x28 | 8 | | setup: data bytes for USB setup, filled with |
+| | | | zeros if not used |
++-----------+--------+------------+---------------------------------------------------+
+| 0x30 | | | URB data. For ISO transfers the padding between |
+| | | | each ISO packets is not transmitted. |
++-----------+--------+------------+---------------------------------------------------+
+
+
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | Allowed transfer_flags | value | control | interrupt | bulk | isochronous |
+ +=========================+============+=========+===========+==========+=============+
+ | URB_SHORT_NOT_OK | 0x00000001 | only in | only in | only in | no |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_ISO_ASAP | 0x00000002 | no | no | no | yes |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_NO_TRANSFER_DMA_MAP | 0x00000004 | yes | yes | yes | yes |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_ZERO_PACKET | 0x00000040 | no | no | only out | no |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_NO_INTERRUPT | 0x00000080 | yes | yes | yes | yes |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_FREE_BUFFER | 0x00000100 | yes | yes | yes | yes |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+ | URB_DIR_MASK | 0x00000200 | yes | yes | yes | yes |
+ +-------------------------+------------+---------+-----------+----------+-------------+
+
+
+USBIP_RET_SUBMIT:
+ Reply for submitting an URB
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 4 | 0x00000003 | command |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | | seqnum: URB sequence number |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 4 | | devid |
++-----------+--------+------------+---------------------------------------------------+
+| 0xC | 4 | | direction: |
+| | | | |
+| | | | - 0: USBIP_DIR_OUT |
+| | | | - 1: USBIP_DIR_IN |
++-----------+--------+------------+---------------------------------------------------+
+| 0x10 | 4 | | ep: endpoint number |
++-----------+--------+------------+---------------------------------------------------+
+| 0x14 | 4 | | status: zero for successful URB transaction, |
+| | | | otherwise some kind of error happened. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x18 | 4 | n | actual_length: number of URB data bytes |
++-----------+--------+------------+---------------------------------------------------+
+| 0x1C | 4 | | start_frame: for an ISO frame the actually |
+| | | | selected frame for transmit. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x20 | 4 | | number_of_packets |
++-----------+--------+------------+---------------------------------------------------+
+| 0x24 | 4 | | error_count |
++-----------+--------+------------+---------------------------------------------------+
+| 0x28 | 8 | | setup: data bytes for USB setup, filled with |
+| | | | zeros if not used |
++-----------+--------+------------+---------------------------------------------------+
+| 0x30 | n | | URB data bytes. For ISO transfers the padding |
+| | | | between each ISO packets is not transmitted. |
++-----------+--------+------------+---------------------------------------------------+
+
+USBIP_CMD_UNLINK:
+ Unlink an URB
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 4 | 0x00000002 | command: URB unlink command |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | | seqnum: URB sequence number to unlink: |
+| | | | |
+| | | | FIXME: |
+| | | | is this so? |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 4 | | devid |
++-----------+--------+------------+---------------------------------------------------+
+| 0xC | 4 | | direction: |
+| | | | |
+| | | | - 0: USBIP_DIR_OUT |
+| | | | - 1: USBIP_DIR_IN |
++-----------+--------+------------+---------------------------------------------------+
+| 0x10 | 4 | | ep: endpoint number: zero |
++-----------+--------+------------+---------------------------------------------------+
+| 0x14 | 4 | | seqnum: the URB sequence number given previously |
+| | | | at USBIP_CMD_SUBMIT.seqnum field |
++-----------+--------+------------+---------------------------------------------------+
+| 0x30 | n | | URB data bytes. For ISO transfers the padding |
+| | | | between each ISO packets is not transmitted. |
++-----------+--------+------------+---------------------------------------------------+
+
+USBIP_RET_UNLINK:
+ Reply for URB unlink
+
++-----------+--------+------------+---------------------------------------------------+
+| Offset | Length | Value | Description |
++===========+========+============+===================================================+
+| 0 | 4 | 0x00000004 | command: reply for the URB unlink command |
++-----------+--------+------------+---------------------------------------------------+
+| 4 | 4 | | seqnum: the unlinked URB sequence number |
++-----------+--------+------------+---------------------------------------------------+
+| 8 | 4 | | devid |
++-----------+--------+------------+---------------------------------------------------+
+| 0xC | 4 | | direction: |
+| | | | |
+| | | | - 0: USBIP_DIR_OUT |
+| | | | - 1: USBIP_DIR_IN |
++-----------+--------+------------+---------------------------------------------------+
+| 0x10 | 4 | | ep: endpoint number |
++-----------+--------+------------+---------------------------------------------------+
+| 0x14 | 4 | | status: This is the value contained in the |
+| | | | urb->status in the URB completition handler. |
+| | | | |
+| | | | FIXME: |
+| | | | a better explanation needed. |
++-----------+--------+------------+---------------------------------------------------+
+| 0x30 | n | | URB data bytes. For ISO transfers the padding |
+| | | | between each ISO packets is not transmitted. |
++-----------+--------+------------+---------------------------------------------------+
diff --git a/Documentation/usb/usbmon.rst b/Documentation/usb/usbmon.rst
new file mode 100644
index 000000000..b0bd51080
--- /dev/null
+++ b/Documentation/usb/usbmon.rst
@@ -0,0 +1,375 @@
+======
+usbmon
+======
+
+Introduction
+============
+
+The name "usbmon" in lowercase refers to a facility in kernel which is
+used to collect traces of I/O on the USB bus. This function is analogous
+to a packet socket used by network monitoring tools such as tcpdump(1)
+or Ethereal. Similarly, it is expected that a tool such as usbdump or
+USBMon (with uppercase letters) is used to examine raw traces produced
+by usbmon.
+
+The usbmon reports requests made by peripheral-specific drivers to Host
+Controller Drivers (HCD). So, if HCD is buggy, the traces reported by
+usbmon may not correspond to bus transactions precisely. This is the same
+situation as with tcpdump.
+
+Two APIs are currently implemented: "text" and "binary". The binary API
+is available through a character device in /dev namespace and is an ABI.
+The text API is deprecated since 2.6.35, but available for convenience.
+
+How to use usbmon to collect raw text traces
+============================================
+
+Unlike the packet socket, usbmon has an interface which provides traces
+in a text format. This is used for two purposes. First, it serves as a
+common trace exchange format for tools while more sophisticated formats
+are finalized. Second, humans can read it in case tools are not available.
+
+To collect a raw text trace, execute following steps.
+
+1. Prepare
+----------
+
+Mount debugfs (it has to be enabled in your kernel configuration), and
+load the usbmon module (if built as module). The second step is skipped
+if usbmon is built into the kernel::
+
+ # mount -t debugfs none_debugs /sys/kernel/debug
+ # modprobe usbmon
+ #
+
+Verify that bus sockets are present:
+
+ # ls /sys/kernel/debug/usb/usbmon
+ 0s 0u 1s 1t 1u 2s 2t 2u 3s 3t 3u 4s 4t 4u
+ #
+
+Now you can choose to either use the socket '0u' (to capture packets on all
+buses), and skip to step #3, or find the bus used by your device with step #2.
+This allows to filter away annoying devices that talk continuously.
+
+2. Find which bus connects to the desired device
+------------------------------------------------
+
+Run "cat /sys/kernel/debug/usb/devices", and find the T-line which corresponds
+to the device. Usually you do it by looking for the vendor string. If you have
+many similar devices, unplug one and compare the two
+/sys/kernel/debug/usb/devices outputs. The T-line will have a bus number.
+
+Example::
+
+ T: Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 0
+ D: Ver= 1.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
+ P: Vendor=0557 ProdID=2004 Rev= 1.00
+ S: Manufacturer=ATEN
+ S: Product=UC100KM V2.00
+
+"Bus=03" means it's bus 3. Alternatively, you can look at the output from
+"lsusb" and get the bus number from the appropriate line. Example:
+
+Bus 003 Device 002: ID 0557:2004 ATEN UC100KM V2.00
+
+3. Start 'cat'
+--------------
+
+::
+
+ # cat /sys/kernel/debug/usb/usbmon/3u > /tmp/1.mon.out
+
+to listen on a single bus, otherwise, to listen on all buses, type::
+
+ # cat /sys/kernel/debug/usb/usbmon/0u > /tmp/1.mon.out
+
+This process will read until it is killed. Naturally, the output can be
+redirected to a desirable location. This is preferred, because it is going
+to be quite long.
+
+4. Perform the desired operation on the USB bus
+-----------------------------------------------
+
+This is where you do something that creates the traffic: plug in a flash key,
+copy files, control a webcam, etc.
+
+5. Kill cat
+-----------
+
+Usually it's done with a keyboard interrupt (Control-C).
+
+At this point the output file (/tmp/1.mon.out in this example) can be saved,
+sent by e-mail, or inspected with a text editor. In the last case make sure
+that the file size is not excessive for your favourite editor.
+
+Raw text data format
+====================
+
+Two formats are supported currently: the original, or '1t' format, and
+the '1u' format. The '1t' format is deprecated in kernel 2.6.21. The '1u'
+format adds a few fields, such as ISO frame descriptors, interval, etc.
+It produces slightly longer lines, but otherwise is a perfect superset
+of '1t' format.
+
+If it is desired to recognize one from the other in a program, look at the
+"address" word (see below), where '1u' format adds a bus number. If 2 colons
+are present, it's the '1t' format, otherwise '1u'.
+
+Any text format data consists of a stream of events, such as URB submission,
+URB callback, submission error. Every event is a text line, which consists
+of whitespace separated words. The number or position of words may depend
+on the event type, but there is a set of words, common for all types.
+
+Here is the list of words, from left to right:
+
+- URB Tag. This is used to identify URBs, and is normally an in-kernel address
+ of the URB structure in hexadecimal, but can be a sequence number or any
+ other unique string, within reason.
+
+- Timestamp in microseconds, a decimal number. The timestamp's resolution
+ depends on available clock, and so it can be much worse than a microsecond
+ (if the implementation uses jiffies, for example).
+
+- Event Type. This type refers to the format of the event, not URB type.
+ Available types are: S - submission, C - callback, E - submission error.
+
+- "Address" word (formerly a "pipe"). It consists of four fields, separated by
+ colons: URB type and direction, Bus number, Device address, Endpoint number.
+ Type and direction are encoded with two bytes in the following manner:
+
+ == == =============================
+ Ci Co Control input and output
+ Zi Zo Isochronous input and output
+ Ii Io Interrupt input and output
+ Bi Bo Bulk input and output
+ == == =============================
+
+ Bus number, Device address, and Endpoint are decimal numbers, but they may
+ have leading zeros, for the sake of human readers.
+
+- URB Status word. This is either a letter, or several numbers separated
+ by colons: URB status, interval, start frame, and error count. Unlike the
+ "address" word, all fields save the status are optional. Interval is printed
+ only for interrupt and isochronous URBs. Start frame is printed only for
+ isochronous URBs. Error count is printed only for isochronous callback
+ events.
+
+ The status field is a decimal number, sometimes negative, which represents
+ a "status" field of the URB. This field makes no sense for submissions, but
+ is present anyway to help scripts with parsing. When an error occurs, the
+ field contains the error code.
+
+ In case of a submission of a Control packet, this field contains a Setup Tag
+ instead of an group of numbers. It is easy to tell whether the Setup Tag is
+ present because it is never a number. Thus if scripts find a set of numbers
+ in this word, they proceed to read Data Length (except for isochronous URBs).
+ If they find something else, like a letter, they read the setup packet before
+ reading the Data Length or isochronous descriptors.
+
+- Setup packet, if present, consists of 5 words: one of each for bmRequestType,
+ bRequest, wValue, wIndex, wLength, as specified by the USB Specification 2.0.
+ These words are safe to decode if Setup Tag was 's'. Otherwise, the setup
+ packet was present, but not captured, and the fields contain filler.
+
+- Number of isochronous frame descriptors and descriptors themselves.
+ If an Isochronous transfer event has a set of descriptors, a total number
+ of them in an URB is printed first, then a word per descriptor, up to a
+ total of 5. The word consists of 3 colon-separated decimal numbers for
+ status, offset, and length respectively. For submissions, initial length
+ is reported. For callbacks, actual length is reported.
+
+- Data Length. For submissions, this is the requested length. For callbacks,
+ this is the actual length.
+
+- Data tag. The usbmon may not always capture data, even if length is nonzero.
+ The data words are present only if this tag is '='.
+
+- Data words follow, in big endian hexadecimal format. Notice that they are
+ not machine words, but really just a byte stream split into words to make
+ it easier to read. Thus, the last word may contain from one to four bytes.
+ The length of collected data is limited and can be less than the data length
+ reported in the Data Length word. In the case of an Isochronous input (Zi)
+ completion where the received data is sparse in the buffer, the length of
+ the collected data can be greater than the Data Length value (because Data
+ Length counts only the bytes that were received whereas the Data words
+ contain the entire transfer buffer).
+
+Examples:
+
+An input control transfer to get a port status::
+
+ d5ea89a0 3575914555 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
+ d5ea89a0 3575914560 C Ci:1:001:0 0 4 = 01050000
+
+An output bulk transfer to send a SCSI command 0x28 (READ_10) in a 31-byte
+Bulk wrapper to a storage device at address 5::
+
+ dd65f0e8 4128379752 S Bo:1:005:2 -115 31 = 55534243 ad000000 00800000 80010a28 20000000 20000040 00000000 000000
+ dd65f0e8 4128379808 C Bo:1:005:2 0 31 >
+
+Raw binary format and API
+=========================
+
+The overall architecture of the API is about the same as the one above,
+only the events are delivered in binary format. Each event is sent in
+the following structure (its name is made up, so that we can refer to it)::
+
+ struct usbmon_packet {
+ u64 id; /* 0: URB ID - from submission to callback */
+ unsigned char type; /* 8: Same as text; extensible. */
+ unsigned char xfer_type; /* ISO (0), Intr, Control, Bulk (3) */
+ unsigned char epnum; /* Endpoint number and transfer direction */
+ unsigned char devnum; /* Device address */
+ u16 busnum; /* 12: Bus number */
+ char flag_setup; /* 14: Same as text */
+ char flag_data; /* 15: Same as text; Binary zero is OK. */
+ s64 ts_sec; /* 16: gettimeofday */
+ s32 ts_usec; /* 24: gettimeofday */
+ int status; /* 28: */
+ unsigned int length; /* 32: Length of data (submitted or actual) */
+ unsigned int len_cap; /* 36: Delivered length */
+ union { /* 40: */
+ unsigned char setup[SETUP_LEN]; /* Only for Control S-type */
+ struct iso_rec { /* Only for ISO */
+ int error_count;
+ int numdesc;
+ } iso;
+ } s;
+ int interval; /* 48: Only for Interrupt and ISO */
+ int start_frame; /* 52: For ISO */
+ unsigned int xfer_flags; /* 56: copy of URB's transfer_flags */
+ unsigned int ndesc; /* 60: Actual number of ISO descriptors */
+ }; /* 64 total length */
+
+These events can be received from a character device by reading with read(2),
+with an ioctl(2), or by accessing the buffer with mmap. However, read(2)
+only returns first 48 bytes for compatibility reasons.
+
+The character device is usually called /dev/usbmonN, where N is the USB bus
+number. Number zero (/dev/usbmon0) is special and means "all buses".
+Note that specific naming policy is set by your Linux distribution.
+
+If you create /dev/usbmon0 by hand, make sure that it is owned by root
+and has mode 0600. Otherwise, unprivileged users will be able to snoop
+keyboard traffic.
+
+The following ioctl calls are available, with MON_IOC_MAGIC 0x92:
+
+ MON_IOCQ_URB_LEN, defined as _IO(MON_IOC_MAGIC, 1)
+
+This call returns the length of data in the next event. Note that majority of
+events contain no data, so if this call returns zero, it does not mean that
+no events are available.
+
+ MON_IOCG_STATS, defined as _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
+
+The argument is a pointer to the following structure::
+
+ struct mon_bin_stats {
+ u32 queued;
+ u32 dropped;
+ };
+
+The member "queued" refers to the number of events currently queued in the
+buffer (and not to the number of events processed since the last reset).
+
+The member "dropped" is the number of events lost since the last call
+to MON_IOCG_STATS.
+
+ MON_IOCT_RING_SIZE, defined as _IO(MON_IOC_MAGIC, 4)
+
+This call sets the buffer size. The argument is the size in bytes.
+The size may be rounded down to the next chunk (or page). If the requested
+size is out of [unspecified] bounds for this kernel, the call fails with
+-EINVAL.
+
+ MON_IOCQ_RING_SIZE, defined as _IO(MON_IOC_MAGIC, 5)
+
+This call returns the current size of the buffer in bytes.
+
+ MON_IOCX_GET, defined as _IOW(MON_IOC_MAGIC, 6, struct mon_get_arg)
+ MON_IOCX_GETX, defined as _IOW(MON_IOC_MAGIC, 10, struct mon_get_arg)
+
+These calls wait for events to arrive if none were in the kernel buffer,
+then return the first event. The argument is a pointer to the following
+structure::
+
+ struct mon_get_arg {
+ struct usbmon_packet *hdr;
+ void *data;
+ size_t alloc; /* Length of data (can be zero) */
+ };
+
+Before the call, hdr, data, and alloc should be filled. Upon return, the area
+pointed by hdr contains the next event structure, and the data buffer contains
+the data, if any. The event is removed from the kernel buffer.
+
+The MON_IOCX_GET copies 48 bytes to hdr area, MON_IOCX_GETX copies 64 bytes.
+
+ MON_IOCX_MFETCH, defined as _IOWR(MON_IOC_MAGIC, 7, struct mon_mfetch_arg)
+
+This ioctl is primarily used when the application accesses the buffer
+with mmap(2). Its argument is a pointer to the following structure::
+
+ struct mon_mfetch_arg {
+ uint32_t *offvec; /* Vector of events fetched */
+ uint32_t nfetch; /* Number of events to fetch (out: fetched) */
+ uint32_t nflush; /* Number of events to flush */
+ };
+
+The ioctl operates in 3 stages.
+
+First, it removes and discards up to nflush events from the kernel buffer.
+The actual number of events discarded is returned in nflush.
+
+Second, it waits for an event to be present in the buffer, unless the pseudo-
+device is open with O_NONBLOCK.
+
+Third, it extracts up to nfetch offsets into the mmap buffer, and stores
+them into the offvec. The actual number of event offsets is stored into
+the nfetch.
+
+ MON_IOCH_MFLUSH, defined as _IO(MON_IOC_MAGIC, 8)
+
+This call removes a number of events from the kernel buffer. Its argument
+is the number of events to remove. If the buffer contains fewer events
+than requested, all events present are removed, and no error is reported.
+This works when no events are available too.
+
+ FIONBIO
+
+The ioctl FIONBIO may be implemented in the future, if there's a need.
+
+In addition to ioctl(2) and read(2), the special file of binary API can
+be polled with select(2) and poll(2). But lseek(2) does not work.
+
+* Memory-mapped access of the kernel buffer for the binary API
+
+The basic idea is simple:
+
+To prepare, map the buffer by getting the current size, then using mmap(2).
+Then, execute a loop similar to the one written in pseudo-code below::
+
+ struct mon_mfetch_arg fetch;
+ struct usbmon_packet *hdr;
+ int nflush = 0;
+ for (;;) {
+ fetch.offvec = vec; // Has N 32-bit words
+ fetch.nfetch = N; // Or less than N
+ fetch.nflush = nflush;
+ ioctl(fd, MON_IOCX_MFETCH, &fetch); // Process errors, too
+ nflush = fetch.nfetch; // This many packets to flush when done
+ for (i = 0; i < nflush; i++) {
+ hdr = (struct ubsmon_packet *) &mmap_area[vec[i]];
+ if (hdr->type == '@') // Filler packet
+ continue;
+ caddr_t data = &mmap_area[vec[i]] + 64;
+ process_packet(hdr, data);
+ }
+ }
+
+Thus, the main idea is to execute only one ioctl per N events.
+
+Although the buffer is circular, the returned headers and data do not cross
+the end of the buffer, so the above pseudo-code does not need any gathering.