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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-02 20:21:17 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-02 20:21:17 +0300
commitc58d4055c054fc6dc72f1be8bc71bd6fff209e48 (patch)
tree56527e28fc65d74d6d5e8397c502ccc87a9ec99b /Documentation/media
parentceb198bb007b84ead867e87a71ffe715c4412b15 (diff)
parent9bb0e9cb04c82d6bf0e72f3207307d621083b801 (diff)
downloadlinux-c58d4055c054fc6dc72f1be8bc71bd6fff209e48.tar.xz
Merge tag 'docs-4.12' of git://git.lwn.net/linux
Pull documentation update from Jonathan Corbet: "A reasonably busy cycle for documentation this time around. There is a new guide for user-space API documents, rather sparsely populated at the moment, but it's a start. Markus improved the infrastructure for converting diagrams. Mauro has converted much of the USB documentation over to RST. Plus the usual set of fixes, improvements, and tweaks. There's a bit more than the usual amount of reaching out of Documentation/ to fix comments elsewhere in the tree; I have acks for those where I could get them" * tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits) docs: Fix a couple typos docs: Fix a spelling error in vfio-mediated-device.txt docs: Fix a spelling error in ioctl-number.txt MAINTAINERS: update file entry for HSI subsystem Documentation: allow installing man pages to a user defined directory Doc/PM: Sync with intel_powerclamp code behavior zr364xx.rst: usb/devices is now at /sys/kernel/debug/ usb.rst: move documentation from proc_usb_info.txt to USB ReST book convert philips.txt to ReST and add to media docs docs-rst: usb: update old usbfs-related documentation arm: Documentation: update a path name docs: process/4.Coding.rst: Fix a couple of document refs docs-rst: fix usb cross-references usb: gadget.h: be consistent at kernel doc macros usb: composite.h: fix two warnings when building docs usb: get rid of some ReST doc build errors usb.rst: get rid of some Sphinx errors usb/URB.txt: convert to ReST and update it usb/persist.txt: convert to ReST and add to driver-api book usb/hotplug.txt: convert to ReST and add to driver-api book ...
Diffstat (limited to 'Documentation/media')
-rw-r--r--Documentation/media/Makefile47
-rw-r--r--Documentation/media/intro.rst6
-rw-r--r--Documentation/media/uapi/dvb/intro.rst6
-rw-r--r--Documentation/media/uapi/v4l/crop.rst4
-rw-r--r--Documentation/media/uapi/v4l/dev-raw-vbi.rst22
-rw-r--r--Documentation/media/uapi/v4l/dev-subdev.rst22
-rw-r--r--Documentation/media/uapi/v4l/field-order.rst11
-rw-r--r--Documentation/media/uapi/v4l/pixfmt-nv12mt.rst8
-rw-r--r--Documentation/media/uapi/v4l/selection-api-003.rst6
-rw-r--r--Documentation/media/uapi/v4l/subdev-formats.rst4
-rw-r--r--Documentation/media/v4l-drivers/index.rst1
-rw-r--r--Documentation/media/v4l-drivers/philips.rst245
-rw-r--r--Documentation/media/v4l-drivers/zr364xx.rst2
13 files changed, 292 insertions, 92 deletions
diff --git a/Documentation/media/Makefile b/Documentation/media/Makefile
index 9b3e70b2cab2..36166952d555 100644
--- a/Documentation/media/Makefile
+++ b/Documentation/media/Makefile
@@ -1,51 +1,6 @@
-# Rules to convert DOT and SVG to Sphinx images
-
-SRC_DIR=$(srctree)/Documentation/media
-
-DOTS = \
- uapi/v4l/pipeline.dot \
-
-IMAGES = \
- typical_media_device.svg \
- uapi/dvb/dvbstb.svg \
- uapi/v4l/bayer.svg \
- uapi/v4l/constraints.svg \
- uapi/v4l/crop.svg \
- uapi/v4l/fieldseq_bt.svg \
- uapi/v4l/fieldseq_tb.svg \
- uapi/v4l/nv12mt.svg \
- uapi/v4l/nv12mt_example.svg \
- uapi/v4l/pipeline.svg \
- uapi/v4l/selection.svg \
- uapi/v4l/subdev-image-processing-full.svg \
- uapi/v4l/subdev-image-processing-scaling-multi-source.svg \
- uapi/v4l/subdev-image-processing-crop.svg \
- uapi/v4l/vbi_525.svg \
- uapi/v4l/vbi_625.svg \
- uapi/v4l/vbi_hsync.svg \
-
-DOTTGT := $(patsubst %.dot,%.svg,$(DOTS))
-IMGDOT := $(patsubst %,$(SRC_DIR)/%,$(DOTTGT))
-
-IMGTGT := $(patsubst %.svg,%.pdf,$(IMAGES))
-IMGPDF := $(patsubst %,$(SRC_DIR)/%,$(IMGTGT))
-
-cmd = $(echo-cmd) $(cmd_$(1))
-
-quiet_cmd_genpdf = GENPDF $2
- cmd_genpdf = convert $2 $3
-
-quiet_cmd_gendot = DOT $2
- cmd_gendot = dot -Tsvg $2 > $3 || { rm -f $3; exit 1; }
-
-%.pdf: %.svg
- @$(call cmd,genpdf,$<,$@)
-
-%.svg: %.dot
- @$(call cmd,gendot,$<,$@)
-
# Rules to convert a .h file to inline RST documentation
+SRC_DIR=$(srctree)/Documentation/media
PARSER = $(srctree)/Documentation/sphinx/parse-headers.pl
UAPI = $(srctree)/include/uapi/linux
KAPI = $(srctree)/include/linux
diff --git a/Documentation/media/intro.rst b/Documentation/media/intro.rst
index 8f7490c9a8ef..9ce2e23a0236 100644
--- a/Documentation/media/intro.rst
+++ b/Documentation/media/intro.rst
@@ -13,9 +13,9 @@ A typical media device hardware is shown at :ref:`typical_media_device`.
.. _typical_media_device:
-.. figure:: typical_media_device.*
- :alt: typical_media_device.pdf / typical_media_device.svg
- :align: center
+.. kernel-figure:: typical_media_device.svg
+ :alt: typical_media_device.svg
+ :align: center
Typical Media Device
diff --git a/Documentation/media/uapi/dvb/intro.rst b/Documentation/media/uapi/dvb/intro.rst
index 2ed5c23102b4..652c4aacd2c6 100644
--- a/Documentation/media/uapi/dvb/intro.rst
+++ b/Documentation/media/uapi/dvb/intro.rst
@@ -55,9 +55,9 @@ Overview
.. _stb_components:
-.. figure:: dvbstb.*
- :alt: dvbstb.pdf / dvbstb.svg
- :align: center
+.. kernel-figure:: dvbstb.svg
+ :alt: dvbstb.svg
+ :align: center
Components of a DVB card/STB
diff --git a/Documentation/media/uapi/v4l/crop.rst b/Documentation/media/uapi/v4l/crop.rst
index be58894c9c89..182565b9ace4 100644
--- a/Documentation/media/uapi/v4l/crop.rst
+++ b/Documentation/media/uapi/v4l/crop.rst
@@ -53,8 +53,8 @@ Cropping Structures
.. _crop-scale:
-.. figure:: crop.*
- :alt: crop.pdf / crop.svg
+.. kernel-figure:: crop.svg
+ :alt: crop.svg
:align: center
Image Cropping, Insertion and Scaling
diff --git a/Documentation/media/uapi/v4l/dev-raw-vbi.rst b/Documentation/media/uapi/v4l/dev-raw-vbi.rst
index baf5f2483927..2e6878b624f6 100644
--- a/Documentation/media/uapi/v4l/dev-raw-vbi.rst
+++ b/Documentation/media/uapi/v4l/dev-raw-vbi.rst
@@ -221,33 +221,29 @@ and always returns default parameters as :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` does
.. _vbi-hsync:
-.. figure:: vbi_hsync.*
- :alt: vbi_hsync.pdf / vbi_hsync.svg
- :align: center
+.. kernel-figure:: vbi_hsync.svg
+ :alt: vbi_hsync.svg
+ :align: center
**Figure 4.1. Line synchronization**
.. _vbi-525:
-.. figure:: vbi_525.*
- :alt: vbi_525.pdf / vbi_525.svg
- :align: center
+.. kernel-figure:: vbi_525.svg
+ :alt: vbi_525.svg
+ :align: center
**Figure 4.2. ITU-R 525 line numbering (M/NTSC and M/PAL)**
-
-
.. _vbi-625:
-.. figure:: vbi_625.*
- :alt: vbi_625.pdf / vbi_625.svg
- :align: center
+.. kernel-figure:: vbi_625.svg
+ :alt: vbi_625.svg
+ :align: center
**Figure 4.3. ITU-R 625 line numbering**
-
-
Remember the VBI image format depends on the selected video standard,
therefore the application must choose a new standard or query the
current standard first. Attempts to read or write data ahead of format
diff --git a/Documentation/media/uapi/v4l/dev-subdev.rst b/Documentation/media/uapi/v4l/dev-subdev.rst
index cd2870180208..f0e762167730 100644
--- a/Documentation/media/uapi/v4l/dev-subdev.rst
+++ b/Documentation/media/uapi/v4l/dev-subdev.rst
@@ -99,9 +99,9 @@ the video sensor and the host image processing hardware.
.. _pipeline-scaling:
-.. figure:: pipeline.*
- :alt: pipeline.pdf / pipeline.svg
- :align: center
+.. kernel-figure:: pipeline.dot
+ :alt: pipeline.dot
+ :align: center
Image Format Negotiation on Pipelines
@@ -404,9 +404,9 @@ selection will refer to the sink pad format dimensions instead.
.. _subdev-image-processing-crop:
-.. figure:: subdev-image-processing-crop.*
- :alt: subdev-image-processing-crop.pdf / subdev-image-processing-crop.svg
- :align: center
+.. kernel-figure:: subdev-image-processing-crop.svg
+ :alt: subdev-image-processing-crop.svg
+ :align: center
**Figure 4.5. Image processing in subdevs: simple crop example**
@@ -421,9 +421,9 @@ pad.
.. _subdev-image-processing-scaling-multi-source:
-.. figure:: subdev-image-processing-scaling-multi-source.*
- :alt: subdev-image-processing-scaling-multi-source.pdf / subdev-image-processing-scaling-multi-source.svg
- :align: center
+.. kernel-figure:: subdev-image-processing-scaling-multi-source.svg
+ :alt: subdev-image-processing-scaling-multi-source.svg
+ :align: center
**Figure 4.6. Image processing in subdevs: scaling with multiple sources**
@@ -437,8 +437,8 @@ an area at location specified by the source crop rectangle from it.
.. _subdev-image-processing-full:
-.. figure:: subdev-image-processing-full.*
- :alt: subdev-image-processing-full.pdf / subdev-image-processing-full.svg
+.. kernel-figure:: subdev-image-processing-full.svg
+ :alt: subdev-image-processing-full.svg
:align: center
**Figure 4.7. Image processing in subdevs: scaling and composition with multiple sinks and sources**
diff --git a/Documentation/media/uapi/v4l/field-order.rst b/Documentation/media/uapi/v4l/field-order.rst
index e05fb1041363..5f3f82cbfa34 100644
--- a/Documentation/media/uapi/v4l/field-order.rst
+++ b/Documentation/media/uapi/v4l/field-order.rst
@@ -141,17 +141,20 @@ enum v4l2_field
Field Order, Top Field First Transmitted
========================================
-.. figure:: fieldseq_tb.*
- :alt: fieldseq_tb.pdf / fieldseq_tb.svg
+.. kernel-figure:: fieldseq_tb.svg
+ :alt: fieldseq_tb.svg
:align: center
+ Field Order, Top Field First Transmitted
+
.. _fieldseq-bt:
Field Order, Bottom Field First Transmitted
===========================================
-.. figure:: fieldseq_bt.*
- :alt: fieldseq_bt.pdf / fieldseq_bt.svg
+.. kernel-figure:: fieldseq_bt.svg
+ :alt: fieldseq_bt.svg
:align: center
+ Field Order, Bottom Field First Transmitted
diff --git a/Documentation/media/uapi/v4l/pixfmt-nv12mt.rst b/Documentation/media/uapi/v4l/pixfmt-nv12mt.rst
index 32d0c8743460..172a3825604e 100644
--- a/Documentation/media/uapi/v4l/pixfmt-nv12mt.rst
+++ b/Documentation/media/uapi/v4l/pixfmt-nv12mt.rst
@@ -33,8 +33,8 @@ Layout of macroblocks in memory is presented in the following figure.
.. _nv12mt:
-.. figure:: nv12mt.*
- :alt: nv12mt.pdf / nv12mt.svg
+.. kernel-figure:: nv12mt.svg
+ :alt: nv12mt.svg
:align: center
V4L2_PIX_FMT_NV12MT macroblock Z shape memory layout
@@ -50,8 +50,8 @@ interleaved. Height of the buffer is aligned to 32.
.. _nv12mt_ex:
-.. figure:: nv12mt_example.*
- :alt: nv12mt_example.pdf / nv12mt_example.svg
+.. kernel-figure:: nv12mt_example.svg
+ :alt: nv12mt_example.svg
:align: center
Example V4L2_PIX_FMT_NV12MT memory layout of macroblocks
diff --git a/Documentation/media/uapi/v4l/selection-api-003.rst b/Documentation/media/uapi/v4l/selection-api-003.rst
index 21686f93c38f..bf7e76dfbdf9 100644
--- a/Documentation/media/uapi/v4l/selection-api-003.rst
+++ b/Documentation/media/uapi/v4l/selection-api-003.rst
@@ -7,9 +7,9 @@ Selection targets
.. _sel-targets-capture:
-.. figure:: selection.*
- :alt: selection.pdf / selection.svg
- :align: center
+.. kernel-figure:: selection.svg
+ :alt: selection.svg
+ :align: center
Cropping and composing targets
diff --git a/Documentation/media/uapi/v4l/subdev-formats.rst b/Documentation/media/uapi/v4l/subdev-formats.rst
index d6152c907b8b..89a1fb959314 100644
--- a/Documentation/media/uapi/v4l/subdev-formats.rst
+++ b/Documentation/media/uapi/v4l/subdev-formats.rst
@@ -1514,8 +1514,8 @@ be named ``MEDIA_BUS_FMT_SRGGB10_2X8_PADHI_LE``.
.. _bayer-patterns:
-.. figure:: bayer.*
- :alt: bayer.pdf / bayer.svg
+.. kernel-figure:: bayer.svg
+ :alt: bayer.svg
:align: center
**Figure 4.8 Bayer Patterns**
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.
+
diff --git a/Documentation/media/v4l-drivers/zr364xx.rst b/Documentation/media/v4l-drivers/zr364xx.rst
index f5280e366826..3d193f01d8bb 100644
--- a/Documentation/media/v4l-drivers/zr364xx.rst
+++ b/Documentation/media/v4l-drivers/zr364xx.rst
@@ -30,7 +30,7 @@ You can try the experience changing the vendor/product ID values (look
at the source code).
You can get these values by looking at /var/log/messages when you plug
-your camera, or by typing : cat /proc/bus/usb/devices.
+your camera, or by typing : cat /sys/kernel/debug/usb/devices.
If you manage to use your cam with this code, you can send me a mail
(royale@zerezo.com) with the name of your cam and a patch if needed.