Add an helper function to parse common device properties in the same
way as v4l2_fwnode_endpoint_parse() parses common endpoint properties.
Parse the 'rotation' and 'orientation' properties from the firmware
interface.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add support for the newly defined V4L2_CID_CAMERA_ORIENTATION
and V4L2_CID_CAMERA_SENSOR_ROTATION read-only controls used to report
the camera device mounting position and orientation respectively.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add documentation for the V4L2_CID_CAMERA_SENSOR_ROTATION camera
control. The newly added read-only control reports the rotation
correction to be applied to images before displaying them to the user.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add documentation for the V4L2_CID_CAMERA_ORIENTATION camera
control. The newly added read-only control reports the camera device
orientation relative to the usage orientation of the system the camera
is installed on.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Replace the 'rotation' property description by providing a definition
relative to the camera sensor pixel array coordinate system and the
captured scene.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add the 'orientation' device property, used to specify the device mounting
position. The property is particularly meaningful for mobile devices
with a well defined usage orientation.
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Remove the TODO items regarding media link creation, these issues are
resolved by moving media link creation to individual entity bound
callbacks and the implementation of the get_fwnode_pad operation.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The entities external to the i.MX6 IPU and i.MX7 now create the links
to their fwnode-endpoint connected entities in their notifier bound
callbacks. Which means imx_media_create_of_links() and
imx_media_create_csi_of_links() are no longer needed and are removed.
However there is still one case in which imx-media needs to create
fwnode-endpoint based links at probe completion. The v4l2-async framework
does not allow multiple subdevice notifiers to contain a duplicate
subdevice in their asd_list. Only the first subdev notifier that discovers
and adds that one subdevice to its asd_list will receive a bound callback
for it. Other subdevices that also have firmware endpoint connections to
this duplicate subdevice will not have it in their asd_list, and thus will
never receive a bound callback for it. In the case of imx-media, the one
duplicate subdevice in question is the i.MX6 MIPI CSI-2 receiver.
Until there is a solution to that problem, rewrite imx_media_create_links()
to add the missing links from the CSI-2 receiver to the CSIs and CSI muxes.
The function is renamed imx_media_create_csi2_links().
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Fix the 1:1 port-id:pad-index assumption for the upstream subdevice, by
searching the upstream subdevice's endpoints for one that maps to the
pad's index. This is carried out by a new reverse mapping function
imx_media_get_pad_fwnode().
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
For i.MX5/6, if the bound subdev is a video mux, it must be one of the
CSI muxes, and for i.MX7, the bound subdev must always be a CSI mux.
So if the bound subdev is a video mux, mark it as a CSI mux with a new
group id IMX_MEDIA_GRP_ID_CSI_MUX.
In the process use the new group id in csi_get_upstream_endpoint(), and
do some cleanup in that function for better readability.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The function imx7_csi_get_upstream_endpoint() is not necessary for
imx7. First, the imx7 CSI only receives from the CSI mux, so much of
the code in there is pointless. Second, it is only used to determine
whether the CSI mux has selected the CSI-2 input or the parallel input.
This can be accomplished much more simply by getting the function type
of selected input entity to the CSI mux.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement a notifier bound op to register media links from the remote
sub-device's source pad(s) to the CSI sink pad.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement a notifier bound op to register media links from the remote
sub-device's source pad(s) to the CSI sink pad.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement a notifier bound op to register media links from the remote
sub-device's source pad(s) to the mipi csi-2 receiver sink pad.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement a notifier bound op to register media links from the remote
sub-device's source pad(s) to the mipi csi-2 receiver sink pad.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement a notifier bound op to register media links from the remote
sub-device's source pad(s) to the video-mux sink pad(s).
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Use v4l2_subdev_get_fwnode_pad_1_to_1() as the get_fwnode_pad operation.
The i.MX7 CSI maps port numbers and pad indexes 1:1.
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Use v4l2_subdev_get_fwnode_pad_1_to_1() as the get_fwnode_pad operation.
The imx7-mipi-csis maps port numbers and pad indexes 1:1.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Use v4l2_subdev_get_fwnode_pad_1_to_1() as the get_fwnode_pad operation.
The MIPI CSI-2 receiver maps port numbers and pad indexes 1:1.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Use v4l2_subdev_get_fwnode_pad_1_to_1() as the get_fwnode_pad operation.
The video mux maps fwnode port numbers and pad indexes 1:1.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The CSI does not have a 1:1 relationship between fwnode port numbers and
pad indexes. In fact the CSI fwnode device is itself a port which is the
sink, containing only a single fwnode endpoint. Implement media_entity
operation get_fwnode_pad to first verify the given endpoint is the CSI's
sink endpoint, and if so return the CSI sink pad index.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The users of v4l2_async_register_fwnode_subdev() have switched to
parsing their endpoints and setting up async sub-device lists in their
notifiers locally, without using the endpoint parsing callbacks. There
are no more users of v4l2_async_register_fwnode_subdev() so this
convenience function can be removed.
This reverts commit 1634f0eded87d1f150e823fa56cd782ea0775eb2.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Instead of using the convenience functions
v4l2_async_notifier_parse_fwnode_endpoints*() or
v4l2_async_register_fwnode_subdev(), parse the input endpoints
and set up the async sub-devices without using callbacks. The drivers
know which ports it must parse and how to handle unconnected remotes,
so it makes the code simpler to transfer control of endpoint parsing
to the driver.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Instead of using the convenience function
v4l2_async_register_fwnode_subdev(), parse the video-mux input endpoints
and set up the async sub-devices without using callbacks. The video-mux
knows which ports it must parse (the input ports) and how to handle
unconnected remotes, so it makes the code simpler to transfer control
of endpoint parsing to the driver.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add functions to create media links between source and sink subdevices,
based on the fwnode endpoint connections between them:
v4l2_create_fwnode_links_to_pad() - create links from a source subdev to
a single sink pad based on fwnode
endpoint connections.
v4l2_create_fwnode_links() - create all links from a source to sink subdev
based on fwnode endpoint connections.
These functions can be used in a sink's v4l2-async notifier subdev
bound callback to make the links from the bound subdev.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add a convenience function that can be used as the .get_fwnode_pad
operation for subdevices that map port numbers and pad indexes 1:1.
The function verifies the endpoint is owned by the subdevice, and if
so returns the endpoint port number.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add a missing pointer to the entity in the media_entity operation
get_fwnode_pad. There are no implementers of this op yet, but a future
entity that does so will almost certainly need a reference to itself
to carry out the work.
operation")
Fixes: ae45cd5efc120 ("[media] media: entity: Add get_fwnode_pad entity
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
When enumerating the frame sizes, the value sent to
imx219_get_format_code should be fse->code
(the code from the ioctl) and not imx219->fmt.code
which is the code set currently in the driver.
Fixes: 22da1d56e982 ("media: i2c: imx219: Add support for RAW8 bit bayer format")
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Reviewed-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Implement the get_selection pad operation for the IMX219 sensor driver.
The supported targets report the sensor's native size, the crop default
rectangle and the crop rectangle.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Since its inclusion in v3.9, no users of the SuperH VEU mem2mem video
processing driver have appeared upstream. All VEU devices in SuperH
board code still bind to the "uio_pdrv_genirq" driver instead.
The original author marked the driver orphaned in v3.15.
Remove the driver; it can always be resurrected from git history when
needed.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Landley <rob@landley.net>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The variable status is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The variable result is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
In ttusb_dec_handle_irq(), buffer[4] is continuously read from memory
three times, without being modified.
To reduce the number of memory reads, buffer[4] is first assigned to a
local variable index, and then index is used to replace buffer[4].
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The variable val is being initializeed with a value that is never read
and it is being updated later with a new value. The initialization
is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The variable bw is being initialized with a value that is
never read and it is being updated later with a new value. The
initialization is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
usleep_range() may take longer than the max argument due to scheduling,
especially under load. This is causing random errors in the transmitted
IR. Remove the usleep_range() in favour of busy-looping with udelay().
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add documentation for the new VIDIOC_SUBDEV_QUERYCAP ioctl.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
While normal video/radio/vbi/swradio nodes have a proper QUERYCAP ioctl
that apps can call to determine that it is indeed a V4L2 device, there
is currently no equivalent for v4l-subdev nodes. Adding this ioctl will
solve that, and it will allow utilities like v4l2-compliance to be used
with these devices as well.
SUBDEV_QUERYCAP currently returns the version and capabilities of the
subdevice. Define a capability flag to report if the subdevice is
registered in read-only mode.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
A sub-device device node can be registered in user space only if the
CONFIG_VIDEO_V4L2_SUBDEV_API Kconfig option is selected. Currently the
open/close file operations and the ioctl handler have some parts of
their implementations guarded by #if
defined(CONFIG_VIDEO_V4L2_SUBDEV_API), while they are actually not
accessible without a video device node registered to user space.
Guard the whole open, close and ioctl handler and provide stubs if the
VIDEO_V4L2_SUBDEV_API Kconfig option is not selected.
This slightly reduces the kernel size when the option is not selected
and simplifies the file ops and ioctl implementations.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add to the V4L2 core a function to register device nodes for video
subdevices in read-only mode.
Registering a device node in read-only mode is useful to expose to
userspace the current sub-device configuration, without allowing
application to change it by using the V4L2 subdevice ioctls.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Document a new kAPI function to register subdev device nodes in read only
mode and for each affected ioctl report how access is restricted.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Update the V4L2 sub-device userspace API introduction to provide more
details on why complex devices might want to register devnodes for the
connected subdevices.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Sphinx 2.4.4 produces this warning:
Documentation/admin-guide/media/ipu3.rst:235: WARNING: Title underline too short.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Rework the documentation to make it easier for the reader to understand
the differences in behavior of this ioctl between MC and non-MC drivers.
Note the addition of the 'video-node-centric' and 'MC-centric' terms to
help understand what the IO_MC capability really means.
Also mention in the beginning that mbus_code is one of the fields that
application should initialize, and add META_OUTPUT as one of the types that
this ioctl supports (that was never added here when the META_OUTPUT buffer
type was added).
Finally document that EINVAL will be returned if mbus_code is unsupported.
Fixes: e5b6b07a1b45 ("media: v4l2: Extend VIDIOC_ENUM_FMT to support MC-centric devices")
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Set the V4L2_CAP_IO_MC capability flag to report this vimc
inputs/outputs are controlled by the media graph.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Set the V4L2_CAP_IO_MC capability flag and remove the driver specific
vidioc_enum_{input,output}, vidioc_g_{input,output} and
vidioc_s_{input,output} callbacks.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Set the V4L2_CAP_IO_MC capability flag and remove the driver specific
vidioc_enum_input, vidioc_g_input and vidioc_s_input callbacks for the
media controller enabled part of the driver. Also add support mbus_code
filtering for format enumeration.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The VIDIOC_ENUM_FMT ioctl enumerates all formats supported by a video
node. For MC-centric devices, its behaviour has always been ill-defined,
with drivers implementing one of the following behaviours:
- No support for VIDIOC_ENUM_FMT at all
- Enumerating all formats supported by the video node, regardless of the
configuration of the pipeline
- Enumerating formats supported by the video node for the active
configuration of the connected subdevice
The first behaviour is obviously useless for applications. The second
behaviour provides the most information, but doesn't offer a way to find
what formats are compatible with a given pipeline configuration. The
third behaviour fixes that, but with the drawback that applications
can't enumerate all supported formats anymore, and have to modify the
active configuration of the pipeline to enumerate formats.
The situation is messy as none of the implemented behaviours are ideal,
and userspace can't predict what will happen as the behaviour is
driver-specific.
To fix this, let's extend the VIDIOC_ENUM_FMT with a missing capability:
enumerating pixel formats for a given media bus code. The media bus code
is passed through the v4l2_fmtdesc structure in a new mbus_code field
(repurposed from the reserved fields). With this capability in place,
applications can enumerate pixel formats for a given media bus code
without modifying the active configuration of the device.
The current behaviour of the ioctl is preserved when the new mbus_code
field is set to 0, ensuring compatibility with existing userspace. The
API extension is documented as mandatory for MC-centric devices (as
advertised through the V4L2_CAP_IO_MC capability), allowing applications
and compliance tools to easily determine the availability of the
VIDIOC_ENUM_FMT extension.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
