Commit Graph

17 Commits

Author SHA1 Message Date
Tuukka Toivonen
47b037a051 [media] v4l2-async: failing functions shouldn't have side effects
v4l2-async had several functions doing some operations and then
not undoing the operations in a failure situation. For example,
v4l2_async_test_notify() moved a subdev into notifier's done list
even if registering the subdev (v4l2_device_register_subdev) failed.
If the subdev was allocated and v4l2_async_register_subdev() called
from the driver's probe() function, as usually, the probe()
function freed the allocated subdev and returned a failure.
Nevertheless, the subdev was still left into the notifier's done
list, causing an access to already freed memory when the notifier
was later unregistered.

A hand-edited call trace leaving freed subdevs into the notifier:

v4l2_async_register_notifier(notifier, asd)
cameradrv_probe
 sd = devm_kzalloc()
 v4l2_async_register_subdev(sd)
  v4l2_async_test_notify(notifier, sd, asd)
   list_move(sd, &notifier->done)
   v4l2_device_register_subdev(notifier->v4l2_dev, sd)
    cameradrv_registered(sd) -> fails
->v4l2_async_register_subdev returns failure
->cameradrv_probe returns failure
->devres frees the allocated sd
->sd was freed but it still remains in the notifier's list.

This patch fixes this and several other cases where a failing
function could leave nodes into a linked list while the caller
might free the node due to a failure.

Signed-off-by: Tuukka Toivonen <tuukka.toivonen@intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-02-03 14:51:56 -02:00
Javi Merino
d2180e0cf7 [media] v4l: async: make v4l2 coexist with devicetree nodes in a dt overlay
In asds configured with V4L2_ASYNC_MATCH_OF, the v4l2 subdev can be
part of a devicetree overlay, for example:

&media_bridge {
	...
	my_port: port@0 {
		#address-cells = <1>;
		#size-cells = <0>;
		reg = <0>;
		ep: endpoint@0 {
			remote-endpoint = <&camera0>;
		};
	};
};

/ {
	fragment@0 {
		target = <&i2c0>;
		__overlay__ {
			my_cam {
				compatible = "foo,bar";
				port {
					camera0: endpoint {
						remote-endpoint = <&my_port>;
						...
					};
				};
			};
		};
	};
};

Each time the overlay is applied, its of_node pointer will be
different.  We are not interested in matching the pointer, what we
want to match is that the path is the one we are expecting.  Change to
use of_node_cmp() so that we continue matching after the overlay has
been removed and reapplied.

Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Javi Merino <javi.merino@kernel.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-02-03 08:05:16 -02:00
Markus Elfring
f9e9c0669f [media] v4l2-async: Use kmalloc_array() in v4l2_async_notifier_unregister()
A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-01-31 07:46:57 -02:00
Javier Martinez Canillas
a53d2f299d [media] v4l2-async: remove unneeded .registered_async callback
The v4l2_subdev_core_ops .registered_async callback was added to notify
a subdev when its entity has been registered with the media device, to
allow for example to modify the media graph (i.e: adding entities/links).

But that's not needed since there is already a .registered callback in
struct v4l2_subdev_internal_ops that's called after the entity has been
registered with the media device in v4l2_device_register_subdev().

Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-24 16:49:45 -03:00
Javier Martinez Canillas
c574b75913 [media] v4l2-async: Don't fail if registered_async isn't implemented
After sub-dev registration in v4l2_async_test_notify(), the v4l2-async
core calls the registered_async callback but if a sub-dev driver does
not implement it, v4l2_subdev_call() will return a -ENOIOCTLCMD which
should not be considered an error.

Reported-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Benoit Parrot <bparrot@ti.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-02-19 08:10:31 -02:00
Javier Martinez Canillas
7c3e1ec1f7 [media] v4l2-async: call registered_async after subdev registration
V4L2 sub-devices might need to do initialization that depends on being
registered with a V4L2 device. As an example, sub-devices with Media
Controller support may need to register entities and create pad links.

Execute the registered_async callback after the sub-device has been
registered with the V4L2 device so the driver can do any needed init.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2016-02-10 09:37:36 -02:00
Sakari Ailus
862176512b v4l: async: Add a pointer to of_node to struct v4l2_subdev, match it
V4L2 async sub-devices are currently matched (OF case) based on the struct
device_node pointer in struct device. LED devices may have more than one
LED, and in that case the OF node to match is not directly the device's
node, but a LED's node.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-06-15 11:37:05 -07:00
Mauro Carvalho Chehab
24e9a47e14 [media] v4l2-async: Don't use dynamic static allocation
Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
	drivers/media/v4l2-core/v4l2-async.c:238:1: warning: 'v4l2_async_notifier_unregister' uses dynamic stack allocation [enabled by default]
Instead, let's enforce a limit for the buffer.
In this specific case, there's a hard limit imposed by V4L2_MAX_SUBDEVS,
with is currently 128. That means that the buffer size can be up to
128x8 = 1024 bytes (on a 64bits kernel), with is too big for stack.
Worse than that, someone could increase it and cause real troubles.
So, let's use dynamically allocated data, instead.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-11-08 09:45:43 -02:00
Sylwester Nawrocki
ceedcc4ede [media] v4l2-async: Use proper list head for iteration over registered subdevs
This fixes regression introduced in commit b426b3a660
[media] V4L: Merge struct v4l2_async_subdev_list with struct v4l2_subdev

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-08-18 09:24:23 -03:00
Laurent Pinchart
8e3fbfee23 [media] v4l: async: Make it safe to unregister unregistered notifier
Calling v4l2_async_notifier_unregister() on a notifier that hasn't been
registered leads to a crash. To simplify drivers, make it safe to
unregister a notifier that has not been registered.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-08-18 08:49:33 -03:00
Sylwester Nawrocki
b426b3a660 [media] V4L: Merge struct v4l2_async_subdev_list with struct v4l2_subdev
By integrating the v4l2-async API internals a bit more with
the core overall the v4l2-async code becomes a bit simpler
and easier to follow.
Acked-and-tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-07-30 15:54:56 -03:00
Sylwester Nawrocki
e8419d0890 [media] V4L: Rename subdev field of struct v4l2_async_notifier
This is a purely cosmetic change. Since the 'subdev' member
points to an array of subdevs make it more explicit by
renaming to the plural form.
Acked-and-tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-07-30 15:53:11 -03:00
Sylwester Nawrocki
e7359f8e66 [media] V4L: Add V4L2_ASYNC_MATCH_OF subdev matching type
Add support for matching by device_node pointer. This allows
the notifier user to simply pass a list of device_node pointers
corresponding to sub-devices.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-07-30 15:52:32 -03:00
Sylwester Nawrocki
cfca7644d7 [media] V4L: Rename v4l2_async_bus_* to v4l2_async_match_*
enum v4l2_async_bus_type also selects a method subdevs are matched
in the notification handlers, rename it to v4l2_async_match_type
so V4L2_ASYNC_MATCH_OF entry can be further added for matching by
device tree node pointer.
Acked-and-tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-07-30 15:52:00 -03:00
Sylwester Nawrocki
3c2ade017a [media] V4L: Drop bus_type check in v4l2-async match functions
These match_* functions are internal callbacks and are always
invoked only after checking asd->bus_type. So drop redundant
checks in match_i2c() and match_platform() functions.
Acked-and-tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-07-30 15:51:13 -03:00
Guennadi Liakhovetski
fe05e141a4 [media] V4L2: fix compilation if CONFIG_I2C is undefined
i2c_verify_client() is only available, if I2C is enabled. Fix v4l2-async.c
compilation if I2C is disabled.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-06-28 14:55:29 -03:00
Guennadi Liakhovetski
e9e310491b [media] V4L2: support asynchronous subdevice registration
Currently bridge device drivers register devices for all subdevices
synchronously, typically, during their probing. E.g. if an I2C CMOS sensor
is attached to a video bridge device, the bridge driver will create an I2C
device and wait for the respective I2C driver to probe. This makes linking
of devices straight forward, but this approach cannot be used with
intrinsically asynchronous and unordered device registration systems like
the Flattened Device Tree. To support such systems this patch adds an
asynchronous subdevice registration framework to V4L2. To use it respective
(e.g. I2C) subdevice drivers must register themselves with the framework.
A bridge driver on the other hand must register notification callbacks,
that will be called upon various related events.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-06-21 16:30:00 -03:00