Documentation/video4linux/zc0301.txt - linux - Git at Google


 	      ZC0301 and ZC0301P Image Processor and Control Chip
 				Driver for Linux
 	      ===================================================

 			       - Documentation -


 Index
 =====
 1.  Copyright
 2.  Disclaimer
 3.  License
 4.  Overview and features
 5.  Module dependencies
 6.  Module loading
 7.  Module parameters
 8.  Supported devices
 9.  Notes for V4L2 application developers
 10. Contact information
 11. Credits


 1. Copyright
 ============
 Copyright (C) 2006-2007 by Luca Risolia <luca.risolia@studio.unibo.it>


 2. Disclaimer
 =============
 This software is not developed or sponsored by Z-Star Microelectronics Corp.
 Trademarks are property of their respective owner.


 3. License
 ==========
 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., 675 Mass Ave, Cambridge, MA 02139, USA.


 4. Overview and features
 ========================
 This driver supports the video interface of the devices mounting the ZC0301 or
 ZC0301P Image Processors and Control Chips.

 The driver relies on the Video4Linux2 and USB core modules. It has been
 designed to run properly on SMP systems as well.

 The latest version of the ZC0301[P] driver can be found at the following URL:
 http://www.linux-projects.org/

 Some of the features of the driver are:

 - full compliance with the Video4Linux2 API (see also "Notes for V4L2
   application developers" paragraph);
 - available mmap or read/poll methods for video streaming through isochronous
   data transfers;
 - automatic detection of image sensor;
 - video format is standard JPEG;
 - dynamic driver control thanks to various module parameters (see "Module
   parameters" paragraph);
 - up to 64 cameras can be handled at the same time; they can be connected and
   disconnected from the host many times without turning off the computer, if
   the system supports hotplugging;


 5. Module dependencies
 ======================
 For it to work properly, the driver needs kernel support for Video4Linux and
 USB.

 The following options of the kernel configuration file must be enabled and
 corresponding modules must be compiled:

 	# Multimedia devices
 	#
 	CONFIG_VIDEO_DEV=m

 	# USB support
 	#
 	CONFIG_USB=m

 In addition, depending on the hardware being used, the modules below are
 necessary:

 	# USB Host Controller Drivers
 	#
 	CONFIG_USB_EHCI_HCD=m
 	CONFIG_USB_UHCI_HCD=m
 	CONFIG_USB_OHCI_HCD=m

 The ZC0301 controller also provides a built-in microphone interface. It is
 supported by the USB Audio driver thanks to the ALSA API:

 	# Sound
 	#
 	CONFIG_SOUND=y

 	# Advanced Linux Sound Architecture
 	#
 	CONFIG_SND=m

 	# USB devices
 	#
 	CONFIG_SND_USB_AUDIO=m

 And finally:

 	# V4L USB devices
 	#
 	CONFIG_USB_ZC0301=m


 6. Module loading
 =================
 To use the driver, it is necessary to load the "zc0301" module into memory
 after every other module required: "videodev", "v4l2_common", "compat_ioctl32",
 "usbcore" and, depending on the USB host controller you have, "ehci-hcd",
 "uhci-hcd" or "ohci-hcd".

 Loading can be done as shown below:

 	[root@localhost home]# modprobe zc0301

 At this point the devices should be recognized. You can invoke "dmesg" to
 analyze kernel messages and verify that the loading process has gone well:

 	[user@localhost home]$ dmesg


 7. Module parameters
 ====================
 Module parameters are listed below:
 -------------------------------------------------------------------------------
 Name:           video_nr
 Type:           short array (min = 0, max = 64)
 Syntax:         <-1|n[,...]>
 Description:    Specify V4L2 minor mode number:
 		-1 = use next available
 		 n = use minor number n
 		You can specify up to 64 cameras this way.
 		For example:
 		video_nr=-1,2,-1 would assign minor number 2 to the second
 		registered camera and use auto for the first one and for every
 		other camera.
 Default:        -1
 -------------------------------------------------------------------------------
 Name:           force_munmap
 Type:           bool array (min = 0, max = 64)
 Syntax:         <0|1[,...]>
 Description:    Force the application to unmap previously mapped buffer memory
 		before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
 		all the applications support this feature. This parameter is
 		specific for each detected camera.
 		0 = do not force memory unmapping
 		1 = force memory unmapping (save memory)
 Default:        0
 -------------------------------------------------------------------------------
 Name:           frame_timeout
 Type:           uint array (min = 0, max = 64)
 Syntax:         <n[,...]>
 Description:    Timeout for a video frame in seconds. This parameter is
 		specific for each detected camera. This parameter can be
 		changed at runtime thanks to the /sys filesystem interface.
 Default:        2
 -------------------------------------------------------------------------------
 Name:           debug
 Type:           ushort
 Syntax:         <n>
 Description:    Debugging information level, from 0 to 3:
 		0 = none (use carefully)
 		1 = critical errors
 		2 = significant informations
 		3 = more verbose messages
 		Level 3 is useful for testing only, when only one device
 		is used at the same time. It also shows some more informations
 		about the hardware being detected. This module parameter can be
 		changed at runtime thanks to the /sys filesystem interface.
 Default:        2
 -------------------------------------------------------------------------------


 8. Supported devices
 ====================
 None of the names of the companies as well as their products will be mentioned
 here. They have never collaborated with the author, so no advertising.

 From the point of view of a driver, what unambiguously identify a device are
 its vendor and product USB identifiers. Below is a list of known identifiers of
 devices mounting the ZC0301 Image Processor and Control Chips:

 Vendor ID  Product ID
 ---------  ----------
 0x041e     0x4017
 0x041e     0x401c
 0x041e     0x401e
 0x041e     0x401f
 0x041e     0x4022
 0x041e     0x4034
 0x041e     0x4035
 0x041e     0x4036
 0x041e     0x403a
 0x0458     0x7007
 0x0458     0x700c
 0x0458     0x700f
 0x046d     0x08ae
 0x055f     0xd003
 0x055f     0xd004
 0x0ac8     0x0301
 0x0ac8     0x301b
 0x0ac8     0x303b
 0x10fd     0x0128
 0x10fd     0x8050
 0x10fd     0x804e

 The list above does not imply that all those devices work with this driver: up
 until now only the ones that mount the following image sensors are supported;
 kernel messages will always tell you whether this is the case:

 Model       Manufacturer
 -----       ------------
 PAS202BCB   PixArt Imaging, Inc.
 PB-0330     Photobit Corporation


 9. Notes for V4L2 application developers
 ========================================
 This driver follows the V4L2 API specifications. In particular, it enforces two
 rules:

 - exactly one I/O method, either "mmap" or "read", is associated with each
 file descriptor. Once it is selected, the application must close and reopen the
 device to switch to the other I/O method;

 - although it is not mandatory, previously mapped buffer memory should always
 be unmapped before calling any "VIDIOC_S_CROP" or "VIDIOC_S_FMT" ioctl's.
 The same number of buffers as before will be allocated again to match the size
 of the new video frames, so you have to map the buffers again before any I/O
 attempts on them.


 10. Contact information
 =======================
 The author may be contacted by e-mail at <luca.risolia@studio.unibo.it>.

 GPG/PGP encrypted e-mail's are accepted. The GPG key ID of the author is
 'FCE635A4'; the public 1024-bit key should be available at any keyserver;
 the fingerprint is: '88E8 F32F 7244 68BA 3958  5D40 99DA 5D2A FCE6 35A4'.


 11. Credits
 ===========
 - Informations about the chip internals needed to enable the I2C protocol have
   been taken from the documentation of the ZC030x Video4Linux1 driver written
   by Andrew Birkett <andy@nobugs.org>;
 - The initialization values of the ZC0301 controller connected to the PAS202BCB
   and PB-0330 image sensors have been taken from the SPCA5XX driver maintained
   by Michel Xhaard <mxhaard@magic.fr>;
 - Stanislav Lechev donated one camera.

	ZC0301 and ZC0301P Image Processor and Control Chip
	Driver for Linux
	===================================================

	- Documentation -


	Index
	=====
	1. Copyright
	2. Disclaimer
	3. License
	4. Overview and features
	5. Module dependencies
	6. Module loading
	7. Module parameters
	8. Supported devices
	9. Notes for V4L2 application developers
	10. Contact information
	11. Credits


	1. Copyright
	============
	Copyright (C) 2006-2007 by Luca Risolia <luca.risolia@studio.unibo.it>


	2. Disclaimer
	=============
	This software is not developed or sponsored by Z-Star Microelectronics Corp.
	Trademarks are property of their respective owner.


	3. License
	==========
	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., 675 Mass Ave, Cambridge, MA 02139, USA.


	4. Overview and features
	========================
	This driver supports the video interface of the devices mounting the ZC0301 or
	ZC0301P Image Processors and Control Chips.

	The driver relies on the Video4Linux2 and USB core modules. It has been
	designed to run properly on SMP systems as well.

	The latest version of the ZC0301[P] driver can be found at the following URL:
	http://www.linux-projects.org/

	Some of the features of the driver are:

	- full compliance with the Video4Linux2 API (see also "Notes for V4L2
	application developers" paragraph);
	- available mmap or read/poll methods for video streaming through isochronous
	data transfers;
	- automatic detection of image sensor;
	- video format is standard JPEG;
	- dynamic driver control thanks to various module parameters (see "Module
	parameters" paragraph);
	- up to 64 cameras can be handled at the same time; they can be connected and
	disconnected from the host many times without turning off the computer, if
	the system supports hotplugging;


	5. Module dependencies
	======================
	For it to work properly, the driver needs kernel support for Video4Linux and
	USB.

	The following options of the kernel configuration file must be enabled and
	corresponding modules must be compiled:

	# Multimedia devices
	#
	CONFIG_VIDEO_DEV=m

	# USB support
	#
	CONFIG_USB=m

	In addition, depending on the hardware being used, the modules below are
	necessary:

	# USB Host Controller Drivers
	#
	CONFIG_USB_EHCI_HCD=m
	CONFIG_USB_UHCI_HCD=m
	CONFIG_USB_OHCI_HCD=m

	The ZC0301 controller also provides a built-in microphone interface. It is
	supported by the USB Audio driver thanks to the ALSA API:

	# Sound
	#
	CONFIG_SOUND=y

	# Advanced Linux Sound Architecture
	#
	CONFIG_SND=m

	# USB devices
	#
	CONFIG_SND_USB_AUDIO=m

	And finally:

	# V4L USB devices
	#
	CONFIG_USB_ZC0301=m


	6. Module loading
	=================
	To use the driver, it is necessary to load the "zc0301" module into memory
	after every other module required: "videodev", "v4l2_common", "compat_ioctl32",
	"usbcore" and, depending on the USB host controller you have, "ehci-hcd",
	"uhci-hcd" or "ohci-hcd".

	Loading can be done as shown below:

	[root@localhost home]# modprobe zc0301

	At this point the devices should be recognized. You can invoke "dmesg" to
	analyze kernel messages and verify that the loading process has gone well:

	[user@localhost home]$ dmesg


	7. Module parameters
	====================
	Module parameters are listed below:
	-------------------------------------------------------------------------------
	Name: video_nr
	Type: short array (min = 0, max = 64)
	Syntax: <-1\|n[,...]>
	Description: Specify V4L2 minor mode number:
	-1 = use next available
	n = use minor number n
	You can specify up to 64 cameras this way.
	For example:
	video_nr=-1,2,-1 would assign minor number 2 to the second
	registered camera and use auto for the first one and for every
	other camera.
	Default: -1
	-------------------------------------------------------------------------------
	Name: force_munmap
	Type: bool array (min = 0, max = 64)
	Syntax: <0\|1[,...]>
	Description: Force the application to unmap previously mapped buffer memory
	before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
	all the applications support this feature. This parameter is
	specific for each detected camera.
	0 = do not force memory unmapping
	1 = force memory unmapping (save memory)
	Default: 0
	-------------------------------------------------------------------------------
	Name: frame_timeout
	Type: uint array (min = 0, max = 64)
	Syntax: <n[,...]>
	Description: Timeout for a video frame in seconds. This parameter is
	specific for each detected camera. This parameter can be
	changed at runtime thanks to the /sys filesystem interface.
	Default: 2
	-------------------------------------------------------------------------------
	Name: debug
	Type: ushort
	Syntax: <n>
	Description: Debugging information level, from 0 to 3:
	0 = none (use carefully)
	1 = critical errors
	2 = significant informations
	3 = more verbose messages
	Level 3 is useful for testing only, when only one device
	is used at the same time. It also shows some more informations
	about the hardware being detected. This module parameter can be
	changed at runtime thanks to the /sys filesystem interface.
	Default: 2
	-------------------------------------------------------------------------------


	8. Supported devices
	====================
	None of the names of the companies as well as their products will be mentioned
	here. They have never collaborated with the author, so no advertising.

	From the point of view of a driver, what unambiguously identify a device are
	its vendor and product USB identifiers. Below is a list of known identifiers of
	devices mounting the ZC0301 Image Processor and Control Chips:

	Vendor ID Product ID
	--------- ----------
	0x041e 0x4017
	0x041e 0x401c
	0x041e 0x401e
	0x041e 0x401f
	0x041e 0x4022
	0x041e 0x4034
	0x041e 0x4035
	0x041e 0x4036
	0x041e 0x403a
	0x0458 0x7007
	0x0458 0x700c
	0x0458 0x700f
	0x046d 0x08ae
	0x055f 0xd003
	0x055f 0xd004
	0x0ac8 0x0301
	0x0ac8 0x301b
	0x0ac8 0x303b
	0x10fd 0x0128
	0x10fd 0x8050
	0x10fd 0x804e

	The list above does not imply that all those devices work with this driver: up
	until now only the ones that mount the following image sensors are supported;
	kernel messages will always tell you whether this is the case:

	Model Manufacturer
	----- ------------
	PAS202BCB PixArt Imaging, Inc.
	PB-0330 Photobit Corporation


	9. Notes for V4L2 application developers
	========================================
	This driver follows the V4L2 API specifications. In particular, it enforces two
	rules:

	- exactly one I/O method, either "mmap" or "read", is associated with each
	file descriptor. Once it is selected, the application must close and reopen the
	device to switch to the other I/O method;

	- although it is not mandatory, previously mapped buffer memory should always
	be unmapped before calling any "VIDIOC_S_CROP" or "VIDIOC_S_FMT" ioctl's.
	The same number of buffers as before will be allocated again to match the size
	of the new video frames, so you have to map the buffers again before any I/O
	attempts on them.


	10. Contact information
	=======================
	The author may be contacted by e-mail at <luca.risolia@studio.unibo.it>.

	GPG/PGP encrypted e-mail's are accepted. The GPG key ID of the author is
	'FCE635A4'; the public 1024-bit key should be available at any keyserver;
	the fingerprint is: '88E8 F32F 7244 68BA 3958 5D40 99DA 5D2A FCE6 35A4'.


	11. Credits
	===========
	- Informations about the chip internals needed to enable the I2C protocol have
	been taken from the documentation of the ZC030x Video4Linux1 driver written
	by Andrew Birkett <andy@nobugs.org>;
	- The initialization values of the ZC0301 controller connected to the PAS202BCB
	and PB-0330 image sensors have been taken from the SPCA5XX driver maintained
	by Michel Xhaard <mxhaard@magic.fr>;
	- Stanislav Lechev donated one camera.