It was possible to unregister an already unregistered v4l2_device struct.
Add a check whether that already happened and just return if that was
the case.
Also refuse to register a v4l2_device if both the dev and name fields are
empty. A warning was already produced in that case, but since the name field
is now used to detect whether or not the v4l2_device was already unregistered
this particular combination should be rejected.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Remove all links of the subdev's media entity after internal_ops
'unregistered' call and right before unregistering the entity from
a media device.
It is assumed here that an unregistered (orphan) media entity cannot
have links to other entities registered to a media device.
It is also assumed the media links should be created/removed with
the media graph's mutex held.
The above implies that the caller of v4l2_device_unregister_subdev()
must not hold the graph's mutex.
Reviewed-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NSakari Ailus <sakari.ailus@iki.fi>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch introduces the use of IS_ENABLED() macro. For example,
replacing:
 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
with:
 #if IS_ENABLED(CONFIG_I2C)
All changes made by this patch respect the same replacement pattern.
Reported-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

When subdev registration fails the subdev v4l2_dev field is left to a
non-NULL value. Later calls to v4l2_device_unregister_subdev() will
consider the subdev as registered and will module_put() the subdev
module without any matching module_get().
Fix this by setting the subdev v4l2_dev field to NULL in
v4l2_device_register_subdev() when the function fails.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: stable@vger.kernel.org
Acked-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

With a filter function you can control more precisely which controls
are added. This is useful in particular for radio device nodes for
combined TV/Radio cards where you want to show just the radio-specific
controls and not controls like brightness.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Currently, the v4l2 core is mixed together with other non-core drivers.
Move them into a separate directory.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

When enumerating an entity, assign the entire entity specification
instead of only the first two words. (This requires giving the
specification union a name.)

So far, no driver actually uses more than two words, but this will
be needed for ALSA entities.
Signed-off-by: NClemens Ladisch <clemens@ladisch.de>
[laurent.pinchart@ideasonboard.com: Rename specification to info]
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Currently only very few drivers actually use video_device nodes, embedded
in struct v4l2_subdev. Allocate these nodes dynamically for those drivers
to save memory for the rest.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

A pending cleanup will mean that module.h won't be implicitly
everywhere anymore.  Make sure the modular drivers in clocksource
are actually calling out for <module.h> explicitly in advance.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

v4l2_device_disconnect() calls dev_get_drvdata() and dev_set_drvdata()
on the device it received in v4l2_device_register(). Get a reference to
the device in v4l2_device_register() to make sure it won't disappear as
long as we need it.
Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Tested-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Unplugging uvc video camera trigger following oops:

eeepc kernel: [ 1393.500719] usb 3-2: USB disconnect, device number 4
eeepc kernel: [ 1393.504351] uvcvideo: Failed to resubmit video URB (-19).
eeepc kernel: [ 1495.428853] BUG: unable to handle kernel paging request at 6b6b6bcb
eeepc kernel: [ 1495.429017] IP: [<b0358d37>] dev_get_drvdata+0x17/0x20
eeepc kernel: [ 1495.429017] *pde = 00000000
eeepc kernel: [ 1495.429017] Oops: 0000 [#1] DEBUG_PAGEALLOC
eeepc kernel: [ 1495.429017]
eeepc kernel: [ 1495.429017] Pid: 3476, comm: cheese Not tainted 3.1.0-rc3-00270-g7a54f5e1-dirty #485 ASUSTeK Computer INC. 900/900
eeepc kernel: [ 1495.429017] EIP: 0060:[<b0358d37>] EFLAGS: 00010202 CPU: 0
eeepc kernel: [ 1495.429017] EIP is at dev_get_drvdata+0x17/0x20
eeepc kernel: [ 1495.429017] EAX: 6b6b6b6b EBX: eb08d870 ECX: 00000000 EDX: eb08d930
eeepc kernel: [ 1495.429017] ESI: eb08d870 EDI: eb08d870 EBP: d3249cac ESP: d3249cac
eeepc kernel: [ 1495.429017]  DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068
eeepc kernel: [ 1495.429017] Process cheese (pid: 3476, ti=d3248000 task=df46d870 task.ti=d3248000)
eeepc kernel: [ 1495.429017] Stack:
eeepc kernel: [ 1495.429017]  d3249cb8 b03e77a1 d307b840 d3249ccc b03e77d1 d307b840 eb08d870 eb08d830
eeepc kernel: [ 1495.429017]  d3249ce4 b03ed3b7 00000246 d307b840 eb08d870 d3021b80 d3249cec b03ed565
eeepc kernel: [ 1495.429017]  d3249cfc b03e044d e8323d10 b06e013c d3249d18 b0355fb9 fffffffe d3249d1c
eeepc kernel: [ 1495.429017] Call Trace:
eeepc kernel: [ 1495.429017]  [<b03e77a1>] v4l2_device_disconnect+0x11/0x30
eeepc kernel: [ 1495.429017]  [<b03e77d1>] v4l2_device_unregister+0x11/0x50
eeepc kernel: [ 1495.429017]  [<b03ed3b7>] uvc_delete+0x37/0x110
eeepc kernel: [ 1495.429017]  [<b03ed565>] uvc_release+0x25/0x30
eeepc kernel: [ 1495.429017]  [<b03e044d>] v4l2_device_release+0x9d/0xc0
eeepc kernel: [ 1495.429017]  [<b0355fb9>] device_release+0x19/0x90
eeepc kernel: [ 1495.429017]  [<b03adfdc>] ? usb_hcd_unlink_urb+0x7c/0x90
eeepc kernel: [ 1495.429017]  [<b026b99c>] kobject_release+0x3c/0x90
eeepc kernel: [ 1495.429017]  [<b026b960>] ? kobject_del+0x30/0x30
eeepc kernel: [ 1495.429017]  [<b026ca4c>] kref_put+0x2c/0x60
eeepc kernel: [ 1495.429017]  [<b026b88d>] kobject_put+0x1d/0x50
eeepc kernel: [ 1495.429017]  [<b03b2385>] ? usb_autopm_put_interface+0x25/0x30
eeepc kernel: [ 1495.429017]  [<b03f0e5d>] ? uvc_v4l2_release+0x5d/0xd0
eeepc kernel: [ 1495.429017]  [<b0355d2f>] put_device+0xf/0x20
eeepc kernel: [ 1495.429017]  [<b03dfa96>] v4l2_release+0x56/0x60
eeepc kernel: [ 1495.429017]  [<b019c8dc>] fput+0xcc/0x220
eeepc kernel: [ 1495.429017]  [<b01990f4>] filp_close+0x44/0x70
eeepc kernel: [ 1495.429017]  [<b012b238>] put_files_struct+0x158/0x180
eeepc kernel: [ 1495.429017]  [<b012b100>] ? put_files_struct+0x20/0x180
eeepc kernel: [ 1495.429017]  [<b012b2a0>] exit_files+0x40/0x50
eeepc kernel: [ 1495.429017]  [<b012b9e7>] do_exit+0x5a7/0x660
eeepc kernel: [ 1495.429017]  [<b0135f72>] ? __dequeue_signal+0x12/0x120
eeepc kernel: [ 1495.429017]  [<b055edf2>] ? _raw_spin_unlock_irq+0x22/0x30
eeepc kernel: [ 1495.429017]  [<b012badc>] do_group_exit+0x3c/0xb0
eeepc kernel: [ 1495.429017]  [<b015792b>] ? trace_hardirqs_on+0xb/0x10
eeepc kernel: [ 1495.429017]  [<b013755f>] get_signal_to_deliver+0x18f/0x570
eeepc kernel: [ 1495.429017]  [<b01020f7>] do_signal+0x47/0x9e0
eeepc kernel: [ 1495.429017]  [<b055edf2>] ? _raw_spin_unlock_irq+0x22/0x30
eeepc kernel: [ 1495.429017]  [<b015792b>] ? trace_hardirqs_on+0xb/0x10
eeepc kernel: [ 1495.429017]  [<b0123300>] ? T.1034+0x30/0xc0
eeepc kernel: [ 1495.429017]  [<b055c45f>] ? schedule+0x29f/0x640
eeepc kernel: [ 1495.429017]  [<b0102ac8>] do_notify_resume+0x38/0x40
eeepc kernel: [ 1495.429017]  [<b055f154>] work_notifysig+0x9/0x11
eeepc kernel: [ 1495.429017] Code: e5 5d 83 f8 01 19 c0 f7 d0 83 e0 f0 c3 8d b4 26 00 00 00 00 55 85 c0 89 e5 75 09 31 c0 5d c3 90 8d 74 26 00 8b 40 04 85 c0 74 f0 <8b> 40 60 5d c3 8d 74 26 00 55 89 e5 53 89 c3 83 ec 04 8b 40 04
eeepc kernel: [ 1495.429017] EIP: [<b0358d37>] dev_get_drvdata+0x17/0x20 SS:ESP 0068:d3249cac
eeepc kernel: [ 1495.429017] CR2: 000000006b6b6bcb
eeepc kernel: [ 1495.466975] uvcvideo: Failed to resubmit video URB (-27).
eeepc kernel: [ 1495.467860] uvcvideo: Failed to resubmit video URB (-27).
eeepc kernel: last message repeated 3 times
eeepc kernel: [ 1495.512610] ---[ end trace 73ec16848794e5a5 ]---

For uvc device, dev->vdev.dev is the &intf->dev,
uvc_delete code is as below:
	usb_put_intf(dev->intf);
	usb_put_dev(dev->udev);

	uvc_status_cleanup(dev);
	uvc_ctrl_cleanup_device(dev);

	if (dev->vdev.dev)
		v4l2_device_unregister(&dev->vdev);

Fix it by get_device in v4l2_device_register and put_device in v4l2_device_disconnect
Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Tested-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

To be consistent with v4l2-ioctl.c.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

If v4l2_device_register_subdev() fails, the reference to the subdev
module taken by the function isn't released. Fix this.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: stable@kernel.org
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The video_device struct has proper ref counting and its release function
will be called when the last user releases it. But no such support was
available for struct v4l2_device. This made it hard to determine when a
USB driver can release the device if it has multiple device nodes.

With one device node it is easy of course, since when the device node is
released, the whole device can be released.

This patch adds refcounting to v4l2_device. When registering device nodes
the v4l2_device refcount will be increased, when releasing device nodes
it will be decreased. The (optional) release function will be called when
the last device node was released.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Integrate the v4l2_prio_state into the core, ready for use.

One struct v4l2_prio_state is added to v4l2_device and a pointer
to a prio state is added to video_device.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

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: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSakari Ailus <sakari.ailus@iki.fi>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

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: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

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: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NVimarsh Zutshi <vimarsh.zutshi@gmail.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Fix a bug in v4l2_device_unregister where the sd pointer can be dereferenced
after it was freed.

Normally the i2c adapter is removed before this function is called. Removing
the adapter will also unregister all subdevs on that adapter, so generally
v4l2_device_unregister has nothing to do. However, in the case of a platform
i2c bus that bus is generally not freed.

In that case, after freeing the i2c subdevice the code will fall into the
second block when it tests if the subdev is a SPI device. But by that time
the subdev is already freed and the kernel oopses.

The fix is trivial: continue with the loop after freeing the i2c or spi
subdevice.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Reported-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Some subdevs need to call into the board code after they are registered
and have a valid struct v4l2_device pointer. The s_config op was abused
for this, but now that it is removed we need a cleaner way of solving this.

So this patch adds a struct with internal ops that the v4l2 core can call.

Currently only two ops exist: register and unregister. Subdevs can implement
these to call the board code and pass it the v4l2_device pointer, which the
board code can then use to get access to the struct that embeds the
v4l2_device.

It is expected that in the future open and close ops will also be added.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The BKL replacement mutex had some serious performance side-effects on
V4L drivers. It is replaced by a better heuristic that works around the
worst of the side-effects.

Read the v4l2-dev.c comments for the whole sorry story. This is a
temporary measure only until we can convert all v4l drivers to use
unlocked_ioctl.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add the calls needed to automatically merge subdev controls into a bridge
control handler.

Hook up the control framework in __video_ioctl2 and video_register_device.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add support SPI bus to v4l2. Useful for control some device with SPI bus like
hardware MPEG2 encoders and etc.
Signed-off-by: NBeholder Intl. Ltd. Dmitry Belimov <d.belimov@gmail.com>
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Fix v4l2-device usage of i2c_unregister_device() and handle the case of
CONFIG_I2C=m & CONFIG_MEDIA_VIDEO=y.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Build fails when CONFIG_I2C=n, so handle that case in the if block:

drivers/built-in.o: In function `v4l2_device_unregister':
(.text+0x157821): undefined reference to `i2c_unregister_device'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Until now I relied on i2c_del_adapter to unregister the i2c_clients for
me, however, if the i2c bus is a platform bus then it is never deleted.

So instead I need to unregister i2c clients when unregistering the
v4l2_device.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add a utility function that can be used to setup the v4l2_device's name
field in a standard manner.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Call v4l2_device_disconnect when the parent of a hotpluggable device
disconnects. This ensures that you do not have a pointer to a device that
is no longer present.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Remain consistent in the naming: fields pointing to v4l2_device should
be called v4l2_dev. There are too many device-like entities without
adding to the confusion by mixing naming conventions.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Some drivers (e.g. for ISA devices) have no parent device because there
is no associated bus driver. Allow the parent device to be NULL in
those cases when registering v4l2_device.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Cc: mchehab@infradead.org
Cc: linux-media@vger.kernel.org
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>

/home/v4l/master/v4l/v4l2-device.c:32:2: warning: Using plain integer as NULL pointer
/home/v4l/master/v4l/v4l2-device.c:64:2: warning: Using plain integer as NULL pointer
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Start implementing a proper v4l2 framework as discussed during the
Linux Plumbers Conference 2008.

Introduces v4l2_device (for device instances) and v4l2_subdev (representing
sub-device instances).
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Reviewed-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NAndy Walls <awalls@radix.net>
Reviewed-by: NDavid Brownell <david-b@pacbell.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>