About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / video4linux / zc0301.txt




Custom Search

Based on kernel version 3.8. Page generated on 2013-02-20 22:08 EST.

1	
2		      ZC0301 and ZC0301P Image Processor and Control Chip
3					Driver for Linux
4		      ===================================================
5	
6				       - Documentation -
7	
8	
9	Index
10	=====
11	1.  Copyright
12	2.  Disclaimer
13	3.  License
14	4.  Overview and features
15	5.  Module dependencies
16	6.  Module loading
17	7.  Module parameters
18	8.  Supported devices
19	9.  Notes for V4L2 application developers
20	10. Contact information
21	11. Credits
22	
23	
24	1. Copyright
25	============
26	Copyright (C) 2006-2007 by Luca Risolia <luca.risolia@studio.unibo.it>
27	
28	
29	2. Disclaimer
30	=============
31	This software is not developed or sponsored by Z-Star Microelectronics Corp.
32	Trademarks are property of their respective owner.
33	
34	
35	3. License
36	==========
37	This program is free software; you can redistribute it and/or modify
38	it under the terms of the GNU General Public License as published by
39	the Free Software Foundation; either version 2 of the License, or
40	(at your option) any later version.
41	
42	This program is distributed in the hope that it will be useful,
43	but WITHOUT ANY WARRANTY; without even the implied warranty of
44	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
45	GNU General Public License for more details.
46	
47	You should have received a copy of the GNU General Public License
48	along with this program; if not, write to the Free Software
49	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
50	
51	
52	4. Overview and features
53	========================
54	This driver supports the video interface of the devices mounting the ZC0301 or
55	ZC0301P Image Processors and Control Chips.
56	
57	The driver relies on the Video4Linux2 and USB core modules. It has been
58	designed to run properly on SMP systems as well.
59	
60	The latest version of the ZC0301[P] driver can be found at the following URL:
61	http://www.linux-projects.org/
62	
63	Some of the features of the driver are:
64	
65	- full compliance with the Video4Linux2 API (see also "Notes for V4L2
66	  application developers" paragraph);
67	- available mmap or read/poll methods for video streaming through isochronous
68	  data transfers;
69	- automatic detection of image sensor;
70	- video format is standard JPEG;
71	- dynamic driver control thanks to various module parameters (see "Module
72	  parameters" paragraph);
73	- up to 64 cameras can be handled at the same time; they can be connected and
74	  disconnected from the host many times without turning off the computer, if
75	  the system supports hotplugging;
76	
77	
78	5. Module dependencies
79	======================
80	For it to work properly, the driver needs kernel support for Video4Linux and
81	USB.
82	
83	The following options of the kernel configuration file must be enabled and
84	corresponding modules must be compiled:
85	
86		# Multimedia devices
87		#
88		CONFIG_VIDEO_DEV=m
89	
90		# USB support
91		#
92		CONFIG_USB=m
93	
94	In addition, depending on the hardware being used, the modules below are
95	necessary:
96	
97		# USB Host Controller Drivers
98		#
99		CONFIG_USB_EHCI_HCD=m
100		CONFIG_USB_UHCI_HCD=m
101		CONFIG_USB_OHCI_HCD=m
102	
103	The ZC0301 controller also provides a built-in microphone interface. It is
104	supported by the USB Audio driver thanks to the ALSA API:
105	
106		# Sound
107		#
108		CONFIG_SOUND=y
109	
110		# Advanced Linux Sound Architecture
111		#
112		CONFIG_SND=m
113	
114		# USB devices
115		#
116		CONFIG_SND_USB_AUDIO=m
117	
118	And finally:
119	
120		# V4L USB devices
121		#
122		CONFIG_USB_ZC0301=m
123	
124	
125	6. Module loading
126	=================
127	To use the driver, it is necessary to load the "zc0301" module into memory
128	after every other module required: "videodev", "v4l2_common", "compat_ioctl32",
129	"usbcore" and, depending on the USB host controller you have, "ehci-hcd",
130	"uhci-hcd" or "ohci-hcd".
131	
132	Loading can be done as shown below:
133	
134		[root@localhost home]# modprobe zc0301
135	
136	At this point the devices should be recognized. You can invoke "dmesg" to
137	analyze kernel messages and verify that the loading process has gone well:
138	
139		[user@localhost home]$ dmesg
140	
141	
142	7. Module parameters
143	====================
144	Module parameters are listed below:
145	-------------------------------------------------------------------------------
146	Name:           video_nr
147	Type:           short array (min = 0, max = 64)
148	Syntax:         <-1|n[,...]>
149	Description:    Specify V4L2 minor mode number:
150			-1 = use next available
151			 n = use minor number n
152			You can specify up to 64 cameras this way.
153			For example:
154			video_nr=-1,2,-1 would assign minor number 2 to the second
155			registered camera and use auto for the first one and for every
156			other camera.
157	Default:        -1
158	-------------------------------------------------------------------------------
159	Name:           force_munmap
160	Type:           bool array (min = 0, max = 64)
161	Syntax:         <0|1[,...]>
162	Description:    Force the application to unmap previously mapped buffer memory
163			before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
164			all the applications support this feature. This parameter is
165			specific for each detected camera.
166			0 = do not force memory unmapping
167			1 = force memory unmapping (save memory)
168	Default:        0
169	-------------------------------------------------------------------------------
170	Name:           frame_timeout
171	Type:           uint array (min = 0, max = 64)
172	Syntax:         <n[,...]>
173	Description:    Timeout for a video frame in seconds. This parameter is
174			specific for each detected camera. This parameter can be
175			changed at runtime thanks to the /sys filesystem interface.
176	Default:        2
177	-------------------------------------------------------------------------------
178	Name:           debug
179	Type:           ushort
180	Syntax:         <n>
181	Description:    Debugging information level, from 0 to 3:
182			0 = none (use carefully)
183			1 = critical errors
184			2 = significant information
185			3 = more verbose messages
186			Level 3 is useful for testing only, when only one device
187			is used at the same time. It also shows some information
188			about the hardware being detected. This module parameter can be
189			changed at runtime thanks to the /sys filesystem interface.
190	Default:        2
191	-------------------------------------------------------------------------------
192	
193	
194	8. Supported devices
195	====================
196	None of the names of the companies as well as their products will be mentioned
197	here. They have never collaborated with the author, so no advertising.
198	
199	From the point of view of a driver, what unambiguously identify a device are
200	its vendor and product USB identifiers. Below is a list of known identifiers of
201	devices mounting the ZC0301 Image Processor and Control Chips:
202	
203	Vendor ID  Product ID
204	---------  ----------
205	0x041e     0x4017
206	0x041e     0x401c
207	0x041e     0x401e
208	0x041e     0x401f
209	0x041e     0x4022
210	0x041e     0x4034
211	0x041e     0x4035
212	0x041e     0x4036
213	0x041e     0x403a
214	0x0458     0x7007
215	0x0458     0x700c
216	0x0458     0x700f
217	0x046d     0x08ae
218	0x055f     0xd003
219	0x055f     0xd004
220	0x0ac8     0x0301
221	0x0ac8     0x301b
222	0x0ac8     0x303b
223	0x10fd     0x0128
224	0x10fd     0x8050
225	0x10fd     0x804e
226	
227	The list above does not imply that all those devices work with this driver: up
228	until now only the ones that mount the following image sensors are supported;
229	kernel messages will always tell you whether this is the case:
230	
231	Model       Manufacturer
232	-----       ------------
233	PAS202BCB   PixArt Imaging, Inc.
234	PB-0330     Photobit Corporation
235	
236	
237	9. Notes for V4L2 application developers
238	========================================
239	This driver follows the V4L2 API specifications. In particular, it enforces two
240	rules:
241	
242	- exactly one I/O method, either "mmap" or "read", is associated with each
243	file descriptor. Once it is selected, the application must close and reopen the
244	device to switch to the other I/O method;
245	
246	- although it is not mandatory, previously mapped buffer memory should always
247	be unmapped before calling any "VIDIOC_S_CROP" or "VIDIOC_S_FMT" ioctl's.
248	The same number of buffers as before will be allocated again to match the size
249	of the new video frames, so you have to map the buffers again before any I/O
250	attempts on them.
251	
252	
253	10. Contact information
254	=======================
255	The author may be contacted by e-mail at <luca.risolia@studio.unibo.it>.
256	
257	GPG/PGP encrypted e-mail's are accepted. The GPG key ID of the author is
258	'FCE635A4'; the public 1024-bit key should be available at any keyserver;
259	the fingerprint is: '88E8 F32F 7244 68BA 3958  5D40 99DA 5D2A FCE6 35A4'.
260	
261	
262	11. Credits
263	===========
264	- Information about the chip internals needed to enable the I2C protocol have
265	  been taken from the documentation of the ZC030x Video4Linux1 driver written
266	  by Andrew Birkett <andy@nobugs.org>;
267	- The initialization values of the ZC0301 controller connected to the PAS202BCB
268	  and PB-0330 image sensors have been taken from the SPCA5XX driver maintained
269	  by Michel Xhaard <mxhaard@magic.fr>;
270	- Stanislav Lechev donated one camera.
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.