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diff --git a/Documentation/usb/et61x251.txt b/Documentation/usb/et61x251.txt deleted file mode 100644 index 29340282ab5..00000000000 --- a/Documentation/usb/et61x251.txt +++ /dev/null @@ -1,314 +0,0 @@ - - ET61X[12]51 PC Camera Controllers - 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. Optional device control through "sysfs" -9. Supported devices -10. Notes for V4L2 application developers -11. Contact information - - -1. Copyright -============ -Copyright (C) 2006 by Luca Risolia <luca.risolia@studio.unibo.it> - - -2. Disclaimer -============= -Etoms is a trademark of Etoms Electronics Corp. -This software is not developed or sponsored by Etoms Electronics. - - -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 ET61X151 -or ET61X251 PC Camera Controllers. - -It's worth to note that Etoms Electronics has never collaborated with the -author during the development of this project; despite several requests, -Etoms Electronics also refused to release enough detailed specifications of -the video compression engine. - -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 ET61X[12]51 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; -- support for any window resolutions and optional panning within the maximum - pixel area of image sensor; -- image downscaling with arbitrary scaling factors from 1 and 2 in both - directions (see "Notes for V4L2 application developers" paragraph); -- two different video formats for uncompressed or compressed data in low or - high compression quality (see also "Notes for V4L2 application developers" - paragraph); -- full support for the capabilities of every possible image sensors that can - be connected to the ET61X[12]51 bridges, including, for istance, red, green, - blue and global gain adjustments and exposure control (see "Supported - devices" paragraph for details); -- use of default color settings for sunlight conditions; -- dynamic I/O interface for both ET61X[12]51 and image sensor control (see - "Optional device control through 'sysfs'" paragraph); -- 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; -- no known bugs. - - -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 - -To enable advanced debugging functionality on the device through /sysfs: - - # Multimedia devices - # - CONFIG_VIDEO_ADV_DEBUG=y - - # 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 - -And finally: - - # USB Multimedia devices - # - CONFIG_USB_ET61X251=m - - -6. Module loading -================= -To use the driver, it is necessary to load the "et61x251" module into memory -after every other module required: "videodev", "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 et61x251 - -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. Optional device control through "sysfs" -========================================== -If the kernel has been compiled with the CONFIG_VIDEO_ADV_DEBUG option enabled, -it is possible to read and write both the ET61X[12]51 and the image sensor -registers by using the "sysfs" filesystem interface. - -There are four files in the /sys/class/video4linux/videoX directory for each -registered camera: "reg", "val", "i2c_reg" and "i2c_val". The first two files -control the ET61X[12]51 bridge, while the other two control the sensor chip. -"reg" and "i2c_reg" hold the values of the current register index where the -following reading/writing operations are addressed at through "val" and -"i2c_val". Their use is not intended for end-users, unless you know what you -are doing. Remember that you must be logged in as root before writing to them. - -As an example, suppose we were to want to read the value contained in the -register number 1 of the sensor register table - which is usually the product -identifier - of the camera registered as "/dev/video0": - - [root@localhost #] cd /sys/class/video4linux/video0 - [root@localhost #] echo 1 > i2c_reg - [root@localhost #] cat i2c_val - -Note that if the sensor registers can not be read, "cat" will fail. -To avoid race conditions, all the I/O accesses to the files are serialized. - - -9. 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 ET61X[12]51 PC camera controllers: - -Vendor ID Product ID ---------- ---------- -0x102c 0x6151 -0x102c 0x6251 -0x102c 0x6253 -0x102c 0x6254 -0x102c 0x6255 -0x102c 0x6256 -0x102c 0x6257 -0x102c 0x6258 -0x102c 0x6259 -0x102c 0x625a -0x102c 0x625b -0x102c 0x625c -0x102c 0x625d -0x102c 0x625e -0x102c 0x625f -0x102c 0x6260 -0x102c 0x6261 -0x102c 0x6262 -0x102c 0x6263 -0x102c 0x6264 -0x102c 0x6265 -0x102c 0x6266 -0x102c 0x6267 -0x102c 0x6268 -0x102c 0x6269 - -The following image sensors are supported: - -Model Manufacturer ------ ------------ -TAS5130D1B Taiwan Advanced Sensor Corporation - -All the available control settings of each image sensor are supported through -the V4L2 interface. - - -10. 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. - -Consistently with the hardware limits, this driver also supports image -downscaling with arbitrary scaling factors from 1 and 2 in both directions. -However, the V4L2 API specifications don't correctly define how the scaling -factor can be chosen arbitrarily by the "negotiation" of the "source" and -"target" rectangles. To work around this flaw, we have added the convention -that, during the negotiation, whenever the "VIDIOC_S_CROP" ioctl is issued, the -scaling factor is restored to 1. - -This driver supports two different video formats: the first one is the "8-bit -Sequential Bayer" format and can be used to obtain uncompressed video data -from the device through the current I/O method, while the second one provides -"raw" compressed video data (without frame headers not related to the -compressed data). The current compression quality may vary from 0 to 1 and can -be selected or queried thanks to the VIDIOC_S_JPEGCOMP and VIDIOC_G_JPEGCOMP -V4L2 ioctl's. - - -11. 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'. |