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authorMauro Carvalho Chehab <mchehab@s-opensource.com>2017-04-16 21:51:08 -0300
committerJonathan Corbet <corbet@lwn.net>2017-04-20 15:31:07 -0600
commit9b06f754133c6b22c9753586c3c2708bc509ff64 (patch)
tree30350a7191e4878dd17566741a4ca3d826b05ebb /Documentation/media
parent8a6a285d61fd0d602859c945892927ef87d26895 (diff)
downloadlinux-9b06f754133c6b22c9753586c3c2708bc509ff64.tar.gz
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 'Documentation/media')
-rw-r--r--Documentation/media/v4l-drivers/index.rst1
-rw-r--r--Documentation/media/v4l-drivers/philips.rst245
2 files changed, 246 insertions, 0 deletions
diff --git a/Documentation/media/v4l-drivers/index.rst b/Documentation/media/v4l-drivers/index.rst
index a606d1cdac13..90fe22a6414a 100644
--- a/Documentation/media/v4l-drivers/index.rst
+++ b/Documentation/media/v4l-drivers/index.rst
@@ -45,6 +45,7 @@ For more details see the file COPYING in the source distribution of Linux.
 	meye
 	omap3isp
 	omap4_camera
+	philips
 	pvrusb2
 	pxa_camera
 	radiotrack
diff --git a/Documentation/media/v4l-drivers/philips.rst b/Documentation/media/v4l-drivers/philips.rst
new file mode 100644
index 000000000000..620bcfea7af0
--- /dev/null
+++ b/Documentation/media/v4l-drivers/philips.rst
@@ -0,0 +1,245 @@
+Philips webcams (pwc driver)
+============================
+
+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.
+