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Based on kernel version 3.16. Page generated on 2014-08-06 21:41 EST.

1				  Linux ACM driver v0.16
2			 (c) 1999 Vojtech Pavlik <vojtech@suse.cz>
3				     Sponsored by SuSE
4	----------------------------------------------------------------------------
5	
6	0. Disclaimer
7	~~~~~~~~~~~~~
8	  This program is free software; you can redistribute it and/or modify it
9	under the terms of the GNU General Public License as published by the Free
10	Software Foundation; either version 2 of the License, or (at your option)
11	any later version.
12	
13	  This program is distributed in the hope that it will be useful, but
14	WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15	or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16	more details.
17	
18	  You should have received a copy of the GNU General Public License along
19	with this program; if not, write to the Free Software Foundation, Inc., 59
20	Temple Place, Suite 330, Boston, MA 02111-1307 USA
21	
22	  Should you need to contact me, the author, you can do so either by e-mail
23	- mail your message to <vojtech@suse.cz>, or by paper mail: Vojtech Pavlik,
24	Ucitelska 1576, Prague 8, 182 00 Czech Republic
25	
26	  For your convenience, the GNU General Public License version 2 is included
27	in the package: See the file COPYING.
28	
29	1. Usage
30	~~~~~~~~
31	  The drivers/usb/class/cdc-acm.c drivers works with USB modems and USB ISDN terminal
32	adapters that conform to the Universal Serial Bus Communication Device Class
33	Abstract Control Model (USB CDC ACM) specification.
34	
35	  Many modems do, here is a list of those I know of:
36	
37		3Com OfficeConnect 56k
38		3Com Voice FaxModem Pro
39		3Com Sportster
40		MultiTech MultiModem 56k
41		Zoom 2986L FaxModem
42		Compaq 56k FaxModem
43		ELSA Microlink 56k
44	
45	  I know of one ISDN TA that does work with the acm driver:
46	
47		3Com USR ISDN Pro TA
48	
49	  Some cell phones also connect via USB. I know the following phones work:
50	
51		SonyEricsson K800i
52	
53	  Unfortunately many modems and most ISDN TAs use proprietary interfaces and
54	thus won't work with this drivers. Check for ACM compliance before buying.
55	
56	  To use the modems you need these modules loaded:
57	
58		usbcore.ko
59		uhci-hcd.ko ohci-hcd.ko or ehci-hcd.ko
60		cdc-acm.ko
61	
62	  After that, the modem[s] should be accessible. You should be able to use
63	minicom, ppp and mgetty with them.
64	
65	2. Verifying that it works
66	~~~~~~~~~~~~~~~~~~~~~~~~~~
67	  The first step would be to check /proc/bus/usb/devices, it should look
68	like this:
69	
70	T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=12  MxCh= 2
71	B:  Alloc=  0/900 us ( 0%), #Int=  0, #Iso=  0
72	D:  Ver= 1.00 Cls=09(hub  ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
73	P:  Vendor=0000 ProdID=0000 Rev= 0.00
74	S:  Product=USB UHCI Root Hub
75	S:  SerialNumber=6800
76	C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr=  0mA
77	I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
78	E:  Ad=81(I) Atr=03(Int.) MxPS=   8 Ivl=255ms
79	T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=12  MxCh= 0
80	D:  Ver= 1.00 Cls=02(comm.) Sub=00 Prot=00 MxPS= 8 #Cfgs=  2
81	P:  Vendor=04c1 ProdID=008f Rev= 2.07
82	S:  Manufacturer=3Com Inc.
83	S:  Product=3Com U.S. Robotics Pro ISDN TA
84	S:  SerialNumber=UFT53A49BVT7
85	C:  #Ifs= 1 Cfg#= 1 Atr=60 MxPwr=  0mA
86	I:  If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=acm
87	E:  Ad=85(I) Atr=02(Bulk) MxPS=  64 Ivl=  0ms
88	E:  Ad=04(O) Atr=02(Bulk) MxPS=  64 Ivl=  0ms
89	E:  Ad=81(I) Atr=03(Int.) MxPS=  16 Ivl=128ms
90	C:* #Ifs= 2 Cfg#= 2 Atr=60 MxPwr=  0mA
91	I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=acm
92	E:  Ad=81(I) Atr=03(Int.) MxPS=  16 Ivl=128ms
93	I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=acm
94	E:  Ad=85(I) Atr=02(Bulk) MxPS=  64 Ivl=  0ms
95	E:  Ad=04(O) Atr=02(Bulk) MxPS=  64 Ivl=  0ms
96	
97	The presence of these three lines (and the Cls= 'comm' and 'data' classes)
98	is important, it means it's an ACM device. The Driver=acm means the acm
99	driver is used for the device. If you see only Cls=ff(vend.) then you're out
100	of luck, you have a device with vendor specific-interface.
101	
102	D:  Ver= 1.00 Cls=02(comm.) Sub=00 Prot=00 MxPS= 8 #Cfgs=  2
103	I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=acm
104	I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=acm
105	
106	In the system log you should see:
107	
108	usb.c: USB new device connect, assigned device number 2
109	usb.c: kmalloc IF c7691fa0, numif 1
110	usb.c: kmalloc IF c7b5f3e0, numif 2
111	usb.c: skipped 4 class/vendor specific interface descriptors
112	usb.c: new device strings: Mfr=1, Product=2, SerialNumber=3
113	usb.c: USB device number 2 default language ID 0x409
114	Manufacturer: 3Com Inc.
115	Product: 3Com U.S. Robotics Pro ISDN TA
116	SerialNumber: UFT53A49BVT7
117	acm.c: probing config 1
118	acm.c: probing config 2
119	ttyACM0: USB ACM device
120	acm.c: acm_control_msg: rq: 0x22 val: 0x0 len: 0x0 result: 0
121	acm.c: acm_control_msg: rq: 0x20 val: 0x0 len: 0x7 result: 7
122	usb.c: acm driver claimed interface c7b5f3e0
123	usb.c: acm driver claimed interface c7b5f3f8
124	usb.c: acm driver claimed interface c7691fa0
125	
126	If all this seems to be OK, fire up minicom and set it to talk to the ttyACM
127	device and try typing 'at'. If it responds with 'OK', then everything is
128	working.
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