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2014-12-23[media] v4l2-framework.txt: document debug attributeHans Verkuil1-2/+23
The debug attribute in /sys/class/video4linux/<devX>/debug was never documented. Add this. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-07-04[media] media: Documentation: remove V4L2_FL_USE_FH_PRIO flagRamakrishnan Muthukrishnan1-7/+1
The V4L2_FL_USE_FH_PRIO has been removed from the code, now remove it from the documentation. Signed-off-by: Ramakrishnan Muthukrishnan <ramakrmu@cisco.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2014-03-14[media] v4l2-pci-skeleton: add a V4L2 PCI skeleton driverHans Verkuil1-0/+4
This example driver uses all the latest frameworks and can serve as a starting point for a new V4L2 PCI driver. Originally written for a presentation on how to use V4L2 frameworks during FOSDEM 2014. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2014-03-05[media] v4l2-framework.txt: add SDR device typeAntti Palosaari1-0/+1
Add SDR device type to v4l2-framework.txt document. Cc: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Antti Palosaari <crope@iki.fi> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-06-28[media] V4L2: add documentation for V4L2 clock helpers and asynchronous probingGuennadi Liakhovetski1-2/+71
Add documentation for the V4L2 clock and V4L2 asynchronous probing APIs to v4l2-framework.txt. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-06-21[media] v4l2-framework: update documentationHans Verkuil1-6/+11
'parent' was renamed to 'dev_parent'. Clarify how/when this should be used. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-06-17[media] v4l2-framework: replace g_chip_ident by g_std in the examplesHans Verkuil1-7/+6
The framework documentation used the g_chip_ident op as an example. This op has been removed, so replace its use in the examples by the g_std op. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Cc: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-01-25Merge branch 'v4l_for_linus' into staging/for_v3.9Mauro Carvalho Chehab1-2/+1
* v4l_for_linus: (464 commits) [media] uvcvideo: Set error_idx properly for S_EXT_CTRLS failures [media] uvcvideo: Cleanup leftovers of partial revert [media] uvcvideo: Return -EACCES when trying to set a read-only control Linux 3.8-rc3 mm: reinstante dropped pmd_trans_splitting() check cred: Remove tgcred pointer from struct cred drm/ttm: fix fence locking in ttm_buffer_object_transfer ARM: clps711x: Fix bad merge of clockevents setup ARM: highbank: save and restore L2 cache and GIC on suspend ARM: highbank: add a power request clear ARM: highbank: fix secondary boot and hotplug ARM: highbank: fix typos with hignbank in power request functions ARM: dts: fix highbank cpu mpidr values ARM: dts: add device_type prop to cpu nodes on Calxeda platforms drm/prime: drop reference on imported dma-buf come from gem xen/netfront: improve truesize tracking ARM: mx5: Fix MX53 flexcan2 clock ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array sctp: fix Kconfig bug in default cookie hmac selection EDAC: Cleanup device deregistering path ... Conflicts: drivers/media/pci/dm1105/dm1105.c drivers/media/platform/soc_camera/mx2_camera.c
2013-01-04Documentation: remove __dev* attributes.Greg Kroah-Hartman1-2/+1
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit from the kernel documentation. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-12-18[media] Documentation: fix outdated statement re. v4l2Nicolas THERY1-2/+1
Fix tense used for describing struct v4l2_fh as it has been added a while ago. Signed-off-by: Nicolas Thery <nicolas.thery@st.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-26[media] Add vfl_dir field documentationHans Verkuil1-1/+9
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-09-25[media] v4l: Documentation: change path of video driversLad, Prabhakar1-1/+1
due to structure change for video drivers, change the description with correct path. Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com> Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-07-07[media] v4l2-framework.txt: Update the locking documentationHans Verkuil1-34/+39
This documents the new queue->lock and how to use it. It also removes the documentation of v4l2_disable_ioctl_locking: this is only used in gspca and will be removed once gspca has been converted to vb2. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l2-dev: rename two functionsHans Verkuil1-3/+3
Rename the function v4l2_dont_use_lock to v4l2_disable_ioctl_locking, and rename v4l2_dont_use_cmd to v4l2_disable_ioctl. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l2-framework.txt: update the core lock documentationHans Verkuil1-5/+5
Thanks to Laurent Pinchart for pointing out that this information was missing. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l2-framework.txt: document v4l2_dont_use_cmdHans Verkuil1-0/+10
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l2-dev: make it possible to skip locking for selected ioctlsHans Verkuil1-3/+24
Using the V4L2 core lock is a very robust method that is usually very good at doing the right thing. But some drivers, particularly USB drivers, may want to prevent the core from taking the lock for specific ioctls, particularly buffer queuing ioctls. The reason is that certain commands like S_CTRL can take a long time to process over USB and all the time the core has the lock, preventing VIDIOC_DQBUF from proceeding, even though a frame may be ready in the queue. This introduces unwanted latency. Since the buffer queuing commands often have their own internal lock it is often not necessary to take the core lock. Drivers can now say that they don't want the core to take the lock for specific ioctls. As it is a specific opt-out it makes it clear to the reviewer that those ioctls will need more care when reviewing. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l: Implement v4l2_subdev_link_validate()Sakari Ailus1-0/+12
v4l2_subdev_link_validate() is the default op for validating a link. In V4L2 subdev context, it is used to call a pad op which performs the proper link check without much extra work. Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-14[media] v4l: Improve sub-device documentation for pad opsSakari Ailus1-0/+9
Document that format related configuration is done through pad ops in case the driver does use the media framework. Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-07[media] v4l2-event: Add v4l2_subscribed_event_opsHans de Goede1-7/+21
Just like with ctrl events, drivers may want to get called back on listener add / remove for other event types too. Rather then special casing all of this in subscribe / unsubscribe event it is better to use ops for this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-04-20[media] V4L: fix incorrect refcountingHans Verkuil1-5/+9
Both radio-keene and dsbr100 did one v4l2_device_get too many. Thus the refcount never became 0 and that causes a memory leak. Also updated the V4L2 framework documentation accordingly. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-11-25[media] v4l2 framework doc: clarify lockingHans Verkuil1-0/+11
high-latency devices. Thanks to Hans de Goede for our discussions on this topic. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Thanks-to: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-28[media] v4l2-framework.txt: update v4l2_event sectionHans Verkuil1-16/+35
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-28[media] v4l2-framework.txt: updated v4l2_fh_init documentationHans Verkuil1-6/+2
v4l2_fh_init now returns void instead of int, updated the doc. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-22[media] v4l2: use new flag to enable core priority handlingHans Verkuil1-1/+6
Rather than guess which driver supports core priority handling, require drivers that do to explicitly set the V4L2_FL_USE_FH_PRIO flag in video_device. Updated the core prio handling accordingly and set the flag in the three drivers that do. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2-framework.txt: document new v4l2_device release() callbackHans Verkuil1-0/+15
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l2-framework.txt: improve v4l2_fh/priority documentationHans Verkuil1-33/+87
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: subdev: Generic ioctl supportLaurent Pinchart1-0/+5
Instead of returning an error when receiving an ioctl call with an unsupported command, forward the call to the subdev core::ioctl handler. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: Make v4l2_subdev inherit from media_entityLaurent Pinchart1-0/+23
V4L2 subdevices are media entities. As such they need to inherit from (include) the media_entity structure. When registering/unregistering the subdevice, the media entity is automatically registered/unregistered. The entity is acquired on device open and released on device close. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: Make video_device inherit from media_entityLaurent Pinchart1-3/+35
V4L2 devices are media entities. As such they need to inherit from (include) the media_entity structure. When registering/unregistering the device, the media entity is automatically registered/unregistered. The entity is acquired on device open and released on device close. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: Add a media_device pointer to the v4l2_device structureLaurent Pinchart1-5/+12
The pointer will later be used to register/unregister media entities when registering/unregistering a v4l2_subdev or a video_device. With the introduction of media devices, device drivers need to store a pointer to a driver-specific structure in the device's drvdata. v4l2_device can't claim ownership of the drvdata anymore. To maintain compatibility with drivers that rely on v4l2_device storing a pointer to itself in the device's drvdata, v4l2_device_register() will keep doing so if the drvdata is NULL. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: subdev: Events supportSakari Ailus1-0/+18
Provide v4l2_subdevs with v4l2_event support. Subdev drivers only need very little to support events. Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Signed-off-by: David Cohen <dacohen@gmail.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: subdev: Control ioctls supportLaurent Pinchart1-0/+16
Pass the control-related ioctls to the subdev driver through the control framework. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-03-22[media] v4l: subdev: Add device node supportLaurent Pinchart1-0/+16
Create a device node named subdevX for every registered subdev. As the device node is registered before the subdev core::s_config function is called, return -EGAIN on open until initialization completes. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Vimarsh Zutshi <vimarsh.zutshi@gmail.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21[media] radio-mr800: fix locking orderHans Verkuil1-1/+1
Don't hold the lock before unregistering the device, since when the device is unregistered the datastruct containing the lock may be freed (if the refcount went to 0). Also fixed the framework documentation that erroneously suggested the wrong locking order as well. Reported-by: David Ellingsworth <david@identd.dyndns.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Acked-by: David Ellingsworth <david@identd.dyndns.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21V4L/DVB: v4l2: add core serialization lockHans Verkuil1-0/+20
Drivers can optionally set a pointer to a mutex in struct video_device. The core will use that to lock before calling open, read, write, unlocked_ioctl, poll, mmap or release. Updated the documentation as well and ensure that v4l2-event knows about the lock: it will unlock it before doing a blocking wait on an event and relock it afterwards. Ensure that the 'video_is_registered' check is done when the lock is held: a typical disconnect will take the lock as well before unregistering the device nodes, so to prevent race conditions the video_is_registered check should also be done with the lock held. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21V4L/DVB: v4l2-dev: after a disconnect any ioctl call will be blockedHans Verkuil1-3/+2
Until now all fops except release and (unlocked_)ioctl returned an error after the device node was unregistered. Extend this as well to the ioctl fops. There is nothing useful that an application can do here and it complicates the driver code unnecessarily. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21V4L/DVB: Documentation: update now that the vtx/videotext API has been removedHans Verkuil1-3/+2
Remove all references to /dev/vtx in the documentation, except for some historical comments in dev-teletext.xml. Documentation/devices.txt is not updated, this will go through Alan Cox who maintains this file. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-10-21V4L/DVB: v4l: Add a v4l2_subdev host private data fieldLaurent Pinchart1-0/+5
The existing priv field stores subdev private data owned by the subdev driver. Host (bridge) drivers might need to store per-subdev host-specific data, such as a pointer to platform data. Add a v4l2_subdev host_priv field to store host-specific data, and rename the existing priv field to dev_priv. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: V4L: Events: Add documentationSakari Ailus1-0/+60
Add documentation on how to use V4L2 events, both for V4L2 drivers and for V4L2 applications. Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: V4L: File handles: Add documentationSakari Ailus1-0/+72
Add documentation on using V4L2 file handles (v4l2_fh) in V4L2 drivers. Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19V4L/DVB: v4l2-framework.txt: fix incorrect statementHans Verkuil1-6/+5
After unregister_device all fileops are blocked, except for ioctls. So it is not just the open that is blocked, others are as well. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26V4L/DVB: V4L2 docs: replace spaces by tabsMauro Carvalho Chehab1-1/+0
CC: Jonathan Corbet <corbet@lwn.net> CC: Reviewed-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-02-26V4L/DVB: V4L2: Add a document describing the videobuf layerJonathan Corbet1-96/+11
Videobuf is a moderately complex API which most V4L2 drivers should use, but its documentation is...sparse. This document attempts to improve the situation. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-16V4L/DVB (13549): v4l: Add video_device_node_name functionLaurent Pinchart1-2/+14
Many drivers access the device number (video_device::v4l2_devnode::num) in order to print the video device node name. Add and use a helper function to retrieve the video_device node name. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-09-19V4L/DVB (12725): v4l: warn when desired devnodenr is in use & add _no_warn ↵Hans Verkuil1-6/+16
function Warn when the desired device node number is already in use, except when the new video_register_device_no_warn function is called since in some use-cases that warning is not relevant. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-09-19V4L/DVB (12722): v4l2-dev: replace 'kernel number' by 'device node number'.Hans Verkuil1-4/+4
The term 'kernel number' is very vague, so replace it with the somewhat more descriptive term 'device node number'. In one place the local variable 'nr' was used to create the device node number of the new device name. This has been replaced with the vdev->num field to more clearly mark this as being the device node number and not the minor number. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-09-19V4L/DVB (12541): v4l: remove video_register_device_indexHans Verkuil1-12/+5
video_register_device_index is never actually called, instead the stream index number is always calculated automatically. This patch removes this function and simplifies the internal get_index function since that can now always just return the first free index. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-09-19V4L/DVB (12540): v4l: simplify v4l2_i2c_new_subdev and friendsHans Verkuil1-10/+6
Rewrite v4l2_i2c_new_subdev as a simplified version of v4l2_i2c_new_subdev_cfg and remove v4l2_i2c_new_probed_subdev and v4l2_i2c_new_probed_subdev_addr. This simplifies this API substantially. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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