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authorMauro Carvalho Chehab <mchehab@s-opensource.com>2017-04-17 03:51:08 +0300
committerJonathan Corbet <corbet@lwn.net>2017-04-21 00:31:07 +0300
commit9b06f754133c6b22c9753586c3c2708bc509ff64 (patch)
tree30350a7191e4878dd17566741a4ca3d826b05ebb /drivers/media/usb/pwc
parent8a6a285d61fd0d602859c945892927ef87d26895 (diff)
downloadlinux-9b06f754133c6b22c9753586c3c2708bc509ff64.tar.xz
convert philips.txt to ReST and add to media docs
The philips.txt file were at the wrong place: it should be, instead, at Documentation/media. Move and convert it. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'drivers/media/usb/pwc')
-rw-r--r--drivers/media/usb/pwc/philips.txt236
1 files changed, 0 insertions, 236 deletions
diff --git a/drivers/media/usb/pwc/philips.txt b/drivers/media/usb/pwc/philips.txt
deleted file mode 100644
index d38dd791511e..000000000000
--- a/drivers/media/usb/pwc/philips.txt
+++ /dev/null
@@ -1,236 +0,0 @@
-This file contains some additional information for the Philips and OEM webcams.
-E-mail: webcam@smcc.demon.nl Last updated: 2004-01-19
-Site: http://www.smcc.demon.nl/webcam/
-
-As of this moment, the following cameras are supported:
- * Philips PCA645
- * Philips PCA646
- * Philips PCVC675
- * Philips PCVC680
- * Philips PCVC690
- * Philips PCVC720/40
- * Philips PCVC730
- * Philips PCVC740
- * Philips PCVC750
- * Askey VC010
- * Creative Labs Webcam 5
- * Creative Labs Webcam Pro Ex
- * Logitech QuickCam 3000 Pro
- * Logitech QuickCam 4000 Pro
- * Logitech QuickCam Notebook Pro
- * Logitech QuickCam Zoom
- * Logitech QuickCam Orbit
- * Logitech QuickCam Sphere
- * Samsung MPC-C10
- * Samsung MPC-C30
- * Sotec Afina Eye
- * AME CU-001
- * Visionite VCS-UM100
- * Visionite VCS-UC300
-
-The main webpage for the Philips driver is at the address above. It contains
-a lot of extra information, a FAQ, and the binary plugin 'PWCX'. This plugin
-contains decompression routines that allow you to use higher image sizes and
-framerates; in addition the webcam uses less bandwidth on the USB bus (handy
-if you want to run more than 1 camera simultaneously). These routines fall
-under a NDA, and may therefore not be distributed as source; however, its use
-is completely optional.
-
-You can build this code either into your kernel, or as a module. I recommend
-the latter, since it makes troubleshooting a lot easier. The built-in
-microphone is supported through the USB Audio class.
-
-When you load the module you can set some default settings for the
-camera; some programs depend on a particular image-size or -format and
-don't know how to set it properly in the driver. The options are:
-
-size
- Can be one of 'sqcif', 'qsif', 'qcif', 'sif', 'cif' or
- 'vga', for an image size of resp. 128x96, 160x120, 176x144,
- 320x240, 352x288 and 640x480 (of course, only for those cameras that
- support these resolutions).
-
-fps
- Specifies the desired framerate. Is an integer in the range of 4-30.
-
-fbufs
- This parameter specifies the number of internal buffers to use for storing
- frames from the cam. This will help if the process that reads images from
- the cam is a bit slow or momentarily busy. However, on slow machines it
- only introduces lag, so choose carefully. The default is 3, which is
- reasonable. You can set it between 2 and 5.
-
-mbufs
- This is an integer between 1 and 10. It will tell the module the number of
- buffers to reserve for mmap(), VIDIOCCGMBUF, VIDIOCMCAPTURE and friends.
- The default is 2, which is adequate for most applications (double
- buffering).
-
- Should you experience a lot of 'Dumping frame...' messages during
- grabbing with a tool that uses mmap(), you might want to increase if.
- However, it doesn't really buffer images, it just gives you a bit more
- slack when your program is behind. But you need a multi-threaded or
- forked program to really take advantage of these buffers.
-
- The absolute maximum is 10, but don't set it too high! Every buffer takes
- up 460 KB of RAM, so unless you have a lot of memory setting this to
- something more than 4 is an absolute waste. This memory is only
- allocated during open(), so nothing is wasted when the camera is not in
- use.
-
-power_save
- When power_save is enabled (set to 1), the module will try to shut down
- the cam on close() and re-activate on open(). This will save power and
- turn off the LED. Not all cameras support this though (the 645 and 646
- don't have power saving at all), and some models don't work either (they
- will shut down, but never wake up). Consider this experimental. By
- default this option is disabled.
-
-compression (only useful with the plugin)
- With this option you can control the compression factor that the camera
- uses to squeeze the image through the USB bus. You can set the
- parameter between 0 and 3:
- 0 = prefer uncompressed images; if the requested mode is not available
- in an uncompressed format, the driver will silently switch to low
- compression.
- 1 = low compression.
- 2 = medium compression.
- 3 = high compression.
-
- High compression takes less bandwidth of course, but it could also
- introduce some unwanted artefacts. The default is 2, medium compression.
- See the FAQ on the website for an overview of which modes require
- compression.
-
- The compression parameter does not apply to the 645 and 646 cameras
- and OEM models derived from those (only a few). Most cams honour this
- parameter.
-
-leds
- This settings takes 2 integers, that define the on/off time for the LED
- (in milliseconds). One of the interesting things that you can do with
- this is let the LED blink while the camera is in use. This:
-
- leds=500,500
-
- will blink the LED once every second. But with:
-
- leds=0,0
-
- the LED never goes on, making it suitable for silent surveillance.
-
- By default the camera's LED is on solid while in use, and turned off
- when the camera is not used anymore.
-
- This parameter works only with the ToUCam range of cameras (720, 730, 740,
- 750) and OEMs. For other cameras this command is silently ignored, and
- the LED cannot be controlled.
-
- Finally: this parameters does not take effect UNTIL the first time you
- open the camera device. Until then, the LED remains on.
-
-dev_hint
- A long standing problem with USB devices is their dynamic nature: you
- never know what device a camera gets assigned; it depends on module load
- order, the hub configuration, the order in which devices are plugged in,
- and the phase of the moon (i.e. it can be random). With this option you
- can give the driver a hint as to what video device node (/dev/videoX) it
- should use with a specific camera. This is also handy if you have two
- cameras of the same model.
-
- A camera is specified by its type (the number from the camera model,
- like PCA645, PCVC750VC, etc) and optionally the serial number (visible
- in /proc/bus/usb/devices). A hint consists of a string with the following
- format:
-
- [type[.serialnumber]:]node
-
- The square brackets mean that both the type and the serialnumber are
- optional, but a serialnumber cannot be specified without a type (which
- would be rather pointless). The serialnumber is separated from the type
- by a '.'; the node number by a ':'.
-
- This somewhat cryptic syntax is best explained by a few examples:
-
- dev_hint=3,5 The first detected cam gets assigned
- /dev/video3, the second /dev/video5. Any
- other cameras will get the first free
- available slot (see below).
-
- dev_hint=645:1,680:2 The PCA645 camera will get /dev/video1,
- and a PCVC680 /dev/video2.
-
- dev_hint=645.0123:3,645.4567:0 The PCA645 camera with serialnumber
- 0123 goes to /dev/video3, the same
- camera model with the 4567 serial
- gets /dev/video0.
-
- dev_hint=750:1,4,5,6 The PCVC750 camera will get /dev/video1, the
- next 3 Philips cams will use /dev/video4
- through /dev/video6.
-
- Some points worth knowing:
- - Serialnumbers are case sensitive and must be written full, including
- leading zeroes (it's treated as a string).
- - If a device node is already occupied, registration will fail and
- the webcam is not available.
- - You can have up to 64 video devices; be sure to make enough device
- nodes in /dev if you want to spread the numbers.
- After /dev/video9 comes /dev/video10 (not /dev/videoA).
- - If a camera does not match any dev_hint, it will simply get assigned
- the first available device node, just as it used to be.
-
-trace
- In order to better detect problems, it is now possible to turn on a
- 'trace' of some of the calls the module makes; it logs all items in your
- kernel log at debug level.
-
- The trace variable is a bitmask; each bit represents a certain feature.
- If you want to trace something, look up the bit value(s) in the table
- below, add the values together and supply that to the trace variable.
-
- Value Value Description Default
- (dec) (hex)
- 1 0x1 Module initialization; this will log messages On
- while loading and unloading the module
-
- 2 0x2 probe() and disconnect() traces On
-
- 4 0x4 Trace open() and close() calls Off
-
- 8 0x8 read(), mmap() and associated ioctl() calls Off
-
- 16 0x10 Memory allocation of buffers, etc. Off
-
- 32 0x20 Showing underflow, overflow and Dumping frame On
- messages
-
- 64 0x40 Show viewport and image sizes Off
-
- 128 0x80 PWCX debugging Off
-
- For example, to trace the open() & read() functions, sum 8 + 4 = 12,
- so you would supply trace=12 during insmod or modprobe. If
- you want to turn the initialization and probing tracing off, set trace=0.
- The default value for trace is 35 (0x23).
-
-
-
-Example:
-
- # modprobe pwc size=cif fps=15 power_save=1
-
-The fbufs, mbufs and trace parameters are global and apply to all connected
-cameras. Each camera has its own set of buffers.
-
-size and fps only specify defaults when you open() the device; this is to
-accommodate some tools that don't set the size. You can change these
-settings after open() with the Video4Linux ioctl() calls. The default of
-defaults is QCIF size at 10 fps.
-
-The compression parameter is semiglobal; it sets the initial compression
-preference for all camera's, but this parameter can be set per camera with
-the VIDIOCPWCSCQUAL ioctl() call.
-
-All parameters are optional.
-