patch-2.3.99-pre4 linux/Documentation/usb/acm.txt

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diff -u --recursive --new-file v2.3.99-pre3/linux/Documentation/usb/acm.txt linux/Documentation/usb/acm.txt
@@ -1,94 +1,138 @@
-The ACM driver works with modems and ISDN TAs that use the USB Abstract
-Control Model standard. 
-
-****************************
-Test it:
-Watch out, the driver is not stable and tested. Sync often, make backups,
-most importand: don't blame me...
-
-Create device files:
-mknod /dev/ttyACM0 c 166 0
-mknod /dev/ttyACM1 c 166 1
-mknod /dev/ttyACM2 c 166 2
-mknod /dev/ttyACM3 c 166 3
-Compile a kernel with support for your host controller (uhci only for now!)
-and support for ACM. Boot this kernel. If you connect your device to the
-USB bus you should see messages like the following:
-
-Jul 19 20:14:29 office kernel: USB new device connect, assigned device number 1
-Jul 19 20:14:29 office kernel: Found 02:09
-Jul 19 20:14:29 office kernel: Found 04:09
-Jul 19 20:14:29 office kernel: Found 05:07
-Jul 19 20:14:29 office last message repeated 2 times
-Jul 19 20:14:29 office kernel: parsed = 39 len = 67
-Jul 19 20:14:29 office kernel: Expected descriptor 04/09, got 02/09 - skipping
-Jul 19 20:14:29 office kernel:    0 09
-Jul 19 20:14:29 office kernel:    1 02
-Jul 19 20:14:29 office kernel:    2 43
-Jul 19 20:14:29 office kernel:    3 00
-Jul 19 20:14:29 office kernel:    4 02
-Jul 19 20:14:29 office kernel:    5 02
-Jul 19 20:14:29 office kernel:    6 04
-Jul 19 20:14:29 office kernel:    7 60
-Jul 19 20:14:29 office kernel:    8 00
-Jul 19 20:14:29 office kernel: Found 04:09
-Jul 19 20:14:29 office kernel: Found 02:09
-Jul 19 20:14:29 office kernel: Found 04:09
-Jul 19 20:14:29 office kernel: Found 05:07
-Jul 19 20:14:29 office kernel: Found 04:09
-Jul 19 20:14:29 office kernel: Found 05:07
-Jul 19 20:14:29 office kernel: Found 05:07
-Jul 19 20:14:29 office kernel: parsed = 67 len = 0
-Jul 19 20:14:29 office kernel: getstringtable
-Jul 19 20:14:29 office kernel: acm_probe
-Jul 19 20:14:29 office kernel: USB ACM found
-
-Watch out for the line:
-Jul 19 20:14:29 office kernel: USB new device connect, assigned device number 1
-and the line:
-Jul 19 20:14:29 office kernel: USB ACM found
-These two lines show that the device was seen by the usb host controller and
-then recognized by the acm driver as a valid device.
-
-If you use a terminal emulation software like minicom with /dev/ttyACM0 you
-should be able to send AT commands to your device and get responses. I've 
-been able to do zmodem downloads to another pc. However downloads from one
-ISDN TA to another ISDN TA connected to the same PC didn't work. Don't
-know why. Flow control is not finised after all and i'd guess there might
-be problems on heavily loades PCs. I also did some tests with ppp but i'm
-not finised with this. There might be a chance to get it working. However
-i'd like to know if your device is recognized as an ACM device. I'm also
-interested if the thing is stable or if it crashes.
-(should i say how it crases?)
-
-You should be able to add and remove devices from the bus. The driver will
-always try to fill up unused ttys. This means if you hotplug devices their
-order may have changed after reboot. This is not the behaviour Linus liked
-to see but it's ok for now. (I hope ;-)
-
-Please report your experiences to me:
-fuerst@in.tum.de
-
-***************************
-I've tested it with:
-3Com ISDN Pro TA.
-
-It should work with (That means i know these devices conform to ACM):
-3Com Office Connect Modem
-3Com Sportster USB (I think that's what it's called)
-
-***************************
-Many thanks to 3Com which did not only support me with hardware but also
-with technical support in USB questions. They also allowed me to do tests in
-their lab. Great!
-
-***************************
-Known bugs:
-Flow control not tested (likely not to work)
-Some tty function calls not implemented (putchar, etc...)
-Huge amounts of debug output (compile in [*] Magic SysRq key and press ALT+PRTSCR+0 )
-Not all mem is freed at close (need terminate irq in hcd)
-
-***************************
-Have fun,
-	Armin Fuerst
+			  Linux ACM driver v0.16
+		 (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/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
+
+  Unfortunately many modems and most ISDN TAs use proprietary interfaces and
+thus won't work with this drivers. Check for ACM compliance before buying.
+
+  The driver (with devfs) creates these devices in /dev/usb/acm:
+
+	crw-r--r--   1 root     root     166,   0 Apr  1 10:49 0
+	crw-r--r--   1 root     root     166,   1 Apr  1 10:49 1
+	crw-r--r--   1 root     root     166,   2 Apr  1 10:49 2
+
+  And so on, up to 31, with the limit being possible to change in acm.c to up
+to 256, so you can use up to 256 USB modems with one computer (you'll need
+three USB cards for that, though).
+
+  If you don't use devfs, then you can create device nodes with the same
+minor/major numbers anywhere you want, but either the above location or
+/dev/usb/ttyACM0 is preferred.
+
+  To use the modems you need these modules loaded:
+
+	usbcore.o
+	usb-[uo]hci.o or uhci.o
+	acm.o
+
+  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 /proc/bus/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.

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