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Based on kernel version 3.13. Page generated on 2014-01-20 22:02 EST.

1	Documentation for dvb-usb-framework module and its devices
2	
3	Idea behind the dvb-usb-framework
4	=================================
5	
6	In March 2005 I got the new Twinhan USB2.0 DVB-T device. They provided specs and a firmware.
7	
8	Quite keen I wanted to put the driver (with some quirks of course) into dibusb.
9	After reading some specs and doing some USB snooping, it realized, that the
10	dibusb-driver would be a complete mess afterwards. So I decided to do it in a
11	different way: With the help of a dvb-usb-framework.
12	
13	The framework provides generic functions (mostly kernel API calls), such as:
14	
15	- Transport Stream URB handling in conjunction with dvb-demux-feed-control
16	  (bulk and isoc are supported)
17	- registering the device for the DVB-API
18	- registering an I2C-adapter if applicable
19	- remote-control/input-device handling
20	- firmware requesting and loading (currently just for the Cypress USB
21	  controllers)
22	- other functions/methods which can be shared by several drivers (such as
23	  functions for bulk-control-commands)
24	- TODO: a I2C-chunker. It creates device-specific chunks of register-accesses
25	  depending on length of a register and the number of values that can be
26	  multi-written and multi-read.
27	
28	The source code of the particular DVB USB devices does just the communication
29	with the device via the bus. The connection between the DVB-API-functionality
30	is done via callbacks, assigned in a static device-description (struct
31	dvb_usb_device) each device-driver has to have.
32	
33	For an example have a look in drivers/media/usb/dvb-usb/vp7045*.
34	
35	Objective is to migrate all the usb-devices (dibusb, cinergyT2, maybe the
36	ttusb; flexcop-usb already benefits from the generic flexcop-device) to use
37	the dvb-usb-lib.
38	
39	TODO: dynamic enabling and disabling of the pid-filter in regard to number of
40	feeds requested.
41	
42	Supported devices
43	========================
44	
45	See the LinuxTV DVB Wiki at www.linuxtv.org for a complete list of
46	cards/drivers/firmwares:
47	
48	http://www.linuxtv.org/wiki/index.php/DVB_USB
49	
50	0. History & News:
51	  2005-06-30 - added support for WideView WT-220U (Thanks to Steve Chang)
52	  2005-05-30 - added basic isochronous support to the dvb-usb-framework
53		       added support for Conexant Hybrid reference design and Nebula DigiTV USB
54	  2005-04-17 - all dibusb devices ported to make use of the dvb-usb-framework
55	  2005-04-02 - re-enabled and improved remote control code.
56	  2005-03-31 - ported the Yakumo/Hama/Typhoon DVB-T USB2.0 device to dvb-usb.
57	  2005-03-30 - first commit of the dvb-usb-module based on the dibusb-source. First device is a new driver for the
58		       TwinhanDTV Alpha / MagicBox II USB2.0-only DVB-T device.
59	
60	  (change from dvb-dibusb to dvb-usb)
61	  2005-03-28 - added support for the AVerMedia AverTV DVB-T USB2.0 device (Thanks to Glen Harris and Jiun-Kuei Jung, AVerMedia)
62	  2005-03-14 - added support for the Typhoon/Yakumo/HAMA DVB-T mobile USB2.0
63	  2005-02-11 - added support for the KWorld/ADSTech Instant DVB-T USB2.0. Thanks a lot to Joachim von Caron
64	  2005-02-02 - added support for the Hauppauge Win-TV Nova-T USB2
65	  2005-01-31 - distorted streaming is gone for USB1.1 devices
66	  2005-01-13 - moved the mirrored pid_filter_table back to dvb-dibusb
67		     - first almost working version for HanfTek UMT-010
68		     - found out, that Yakumo/HAMA/Typhoon are predecessors of the HanfTek UMT-010
69	  2005-01-10 - refactoring completed, now everything is very delightful
70		     - tuner quirks for some weird devices (Artec T1 AN2235 device has sometimes a
71		       Panasonic Tuner assembled). Tunerprobing implemented. Thanks a lot to Gunnar Wittich.
72	  2004-12-29 - after several days of struggling around bug of no returning URBs fixed.
73	  2004-12-26 - refactored the dibusb-driver, splitted into separate files
74		     - i2c-probing enabled
75	  2004-12-06 - possibility for demod i2c-address probing
76		     - new usb IDs (Compro, Artec)
77	  2004-11-23 - merged changes from DiB3000MC_ver2.1
78		     - revised the debugging
79		     - possibility to deliver the complete TS for USB2.0
80	  2004-11-21 - first working version of the dib3000mc/p frontend driver.
81	  2004-11-12 - added additional remote control keys. Thanks to Uwe Hanke.
82	  2004-11-07 - added remote control support. Thanks to David Matthews.
83	  2004-11-05 - added support for a new devices (Grandtec/Avermedia/Artec)
84		     - merged my changes (for dib3000mb/dibusb) to the FE_REFACTORING, because it became HEAD
85		     - moved transfer control (pid filter, fifo control) from usb driver to frontend, it seems
86		       better settled there (added xfer_ops-struct)
87		     - created a common files for frontends (mc/p/mb)
88	  2004-09-28 - added support for a new device (Unknown, vendor ID is Hyper-Paltek)
89	  2004-09-20 - added support for a new device (Compro DVB-U2000), thanks
90		       to Amaury Demol for reporting
91		     - changed usb TS transfer method (several urbs, stopping transfer
92		       before setting a new pid)
93	  2004-09-13 - added support for a new device (Artec T1 USB TVBOX), thanks
94		       to Christian Motschke for reporting
95	  2004-09-05 - released the dibusb device and dib3000mb-frontend driver
96	
97	  (old news for vp7041.c)
98	  2004-07-15 - found out, by accident, that the device has a TUA6010XS for
99		       PLL
100	  2004-07-12 - figured out, that the driver should also work with the
101		       CTS Portable (Chinese Television System)
102	  2004-07-08 - firmware-extraction-2.422-problem solved, driver is now working
103		       properly with firmware extracted from 2.422
104		     - #if for 2.6.4 (dvb), compile issue
105		     - changed firmware handling, see vp7041.txt sec 1.1
106	  2004-07-02 - some tuner modifications, v0.1, cleanups, first public
107	  2004-06-28 - now using the dvb_dmx_swfilter_packets, everything
108		       runs fine now
109	  2004-06-27 - able to watch and switching channels (pre-alpha)
110		     - no section filtering yet
111	  2004-06-06 - first TS received, but kernel oops :/
112	  2004-05-14 - firmware loader is working
113	  2004-05-11 - start writing the driver
114	
115	1. How to use?
116	1.1. Firmware
117	
118	Most of the USB drivers need to download a firmware to the device before start
119	working.
120	
121	Have a look at the Wikipage for the DVB-USB-drivers to find out, which firmware
122	you need for your device:
123	
124	http://www.linuxtv.org/wiki/index.php/DVB_USB
125	
126	1.2. Compiling
127	
128	Since the driver is in the linux kernel, activating the driver in
129	your favorite config-environment should sufficient. I recommend
130	to compile the driver as module. Hotplug does the rest.
131	
132	If you use dvb-kernel enter the build-2.6 directory run 'make' and 'insmod.sh
133	load' afterwards.
134	
135	1.3. Loading the drivers
136	
137	Hotplug is able to load the driver, when it is needed (because you plugged
138	in the device).
139	
140	If you want to enable debug output, you have to load the driver manually and
141	from within the dvb-kernel cvs repository.
142	
143	first have a look, which debug level are available:
144	
145	modinfo dvb-usb
146	modinfo dvb-usb-vp7045
147	etc.
148	
149	modprobe dvb-usb debug=<level>
150	modprobe dvb-usb-vp7045 debug=<level>
151	etc.
152	
153	should do the trick.
154	
155	When the driver is loaded successfully, the firmware file was in
156	the right place and the device is connected, the "Power"-LED should be
157	turned on.
158	
159	At this point you should be able to start a dvb-capable application. I'm use
160	(t|s)zap, mplayer and dvbscan to test the basics. VDR-xine provides the
161	long-term test scenario.
162	
163	2. Known problems and bugs
164	
165	- Don't remove the USB device while running an DVB application, your system
166	  will go crazy or die most likely.
167	
168	2.1. Adding support for devices
169	
170	TODO
171	
172	2.2. USB1.1 Bandwidth limitation
173	
174	A lot of the currently supported devices are USB1.1 and thus they have a
175	maximum bandwidth of about 5-6 MBit/s when connected to a USB2.0 hub.
176	This is not enough for receiving the complete transport stream of a
177	DVB-T channel (which is about 16 MBit/s). Normally this is not a
178	problem, if you only want to watch TV (this does not apply for HDTV),
179	but watching a channel while recording another channel on the same
180	frequency simply does not work very well. This applies to all USB1.1
181	DVB-T devices, not just the dvb-usb-devices)
182	
183	The bug, where the TS is distorted by a heavy usage of the device is gone
184	definitely. All dvb-usb-devices I was using (Twinhan, Kworld, DiBcom) are
185	working like charm now with VDR. Sometimes I even was able to record a channel
186	and watch another one.
187	
188	2.3. Comments
189	
190	Patches, comments and suggestions are very very welcome.
191	
192	3. Acknowledgements
193	   Amaury Demol (ademol@dibcom.fr) and Francois Kanounnikoff from DiBcom for
194	    providing specs, code and help, on which the dvb-dibusb, dib3000mb and
195	    dib3000mc are based.
196	
197	   David Matthews for identifying a new device type (Artec T1 with AN2235)
198	    and for extending dibusb with remote control event handling. Thank you.
199	
200	   Alex Woods for frequently answering question about usb and dvb
201	    stuff, a big thank you.
202	
203	   Bernd Wagner for helping with huge bug reports and discussions.
204	
205	   Gunnar Wittich and Joachim von Caron for their trust for providing
206	    root-shells on their machines to implement support for new devices.
207	
208	   Allan Third and Michael Hutchinson for their help to write the Nebula
209	    digitv-driver.
210	
211	   Glen Harris for bringing up, that there is a new dibusb-device and Jiun-Kuei
212	    Jung from AVerMedia who kindly provided a special firmware to get the device
213	    up and running in Linux.
214	
215	   Jennifer Chen, Jeff and Jack from Twinhan for kindly supporting by
216		writing the vp7045-driver.
217	
218	   Steve Chang from WideView for providing information for new devices and
219		firmware files.
220	
221	   Michael Paxton for submitting remote control keymaps.
222	
223	   Some guys on the linux-dvb mailing list for encouraging me.
224	
225	   Peter Schildmann >peter.schildmann-nospam-at-web.de< for his
226	    user-level firmware loader, which saves a lot of time
227	    (when writing the vp7041 driver)
228	
229	   Ulf Hermenau for helping me out with traditional chinese.
230	
231	   André Smoktun and Christian Frömmel for supporting me with
232	    hardware and listening to my problems very patiently.
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