Initialise timing struct in cio2_hw_init() to zero in order to avoid a
compiler warning. The warning was a false positive.

Reported-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Initialise best_div local variable to avoid a compiler warning. The
warning was harmless though.

Reported-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

The current error-checking of me->stages in sh_css_sp_init_pipeline()
has some issues / weirdness:

1. It is checked at the top of the function, but only using the atomisp
   custom assert() macro which e.g. smatch does not recognize

2. It is first dereferenced in "first_binary = me->stages->binary", but
   outside of the assert it is checked much later, triggering the following
   smatch warning:

drivers/staging/media/atomisp/pci/sh_css_sp.c:1255 sh_css_sp_init_pipeline()
warn: variable dereferenced before check 'me->stages' (see line 1224)

Drop the custom assert() calls (note 'me' is never NULL) and instead add
a regular check for me->stages not being set.

Reported-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Closes: https://lore.kernel.org/linux-media/7c8fc5b4-280e-844e-cdf5-b6ec2a1616aa@xs4all.nl/


Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

The atomisp code base has a custom assert() macro, a couple of functions
use this in a construction like the following:

   assert(pipe);
   assert(pipe->stream);
   if ((!pipe) || (!pipe->stream)) {
           ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
                               "allocate_mipi_frames(%p) exit: ...\n",
                               pipe);
           return -EINVAL;
   }

The second assert is seen by smatch as dereferencing "pipe" in the above
example (and dereferencing "dvs_6axis_config" in the other case).

Following by the dereferenced variable being checked (a second time)
in the following if () statement.

This triggers the following smatch warnings:
drivers/staging/media/atomisp/pci/sh_css_mipi.c:356 allocate_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 355)
drivers/staging/media/atomisp/pci/sh_css_mipi.c:562 send_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 561)
drivers/staging/media/atomisp/pci/sh_css_param_dvs.c:208 free_dvs_6axis_table() warn: variable dereferenced before check 'dvs_6axis_config' (see line 206)

The custom assert() macro actually expands to a BUG() call and BUG()
calls should not be used in the kernel.

Remove the assert() calls to fix the smatch warnings and in case of
[allocate|send]_mipi_frames() also remove the if () return -EINVAL
block since these functions are never called with a NULL pipe.

Reported-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

The asd is a sub-structure of the main driver data struct, so it is
never NULL. Drop the unnecessary NULL checks in a couple of places.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-media/533f6930-434a-45f3-afff-127003fa64c9@moroto.mountain/


Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

The if statement that compares msgs[i].len != 3 is always false because
it is in a code block where msg[i].len is equal to 3. The check is
redundant and can be removed.

As detected by cppcheck static analysis:
drivers/media/usb/go7007/go7007-i2c.c:168:20: warning: Opposite inner
'if' condition leads to a dead code block. [oppositeInnerCondition]

Link: https://lore.kernel.org/linux-media/20230727174007.635572-1-colin.i.king@gmail.com



Fixes: 866b8695 ("Staging: add the go7007 video driver")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

This code was previously part of the VIDEO_IPU3_CIO2 driver, which could
be built-in or a loadable module, but after the move it turned into a
builtin-only driver. This fails to link when the I2C subsystem is a
module:

x86_64-linux-ld: drivers/media/pci/intel/ipu-bridge.o: in function `ipu_bridge_unregister_sensors':
ipu-bridge.c:(.text+0x50): undefined reference to `i2c_unregister_device'
x86_64-linux-ld: drivers/media/pci/intel/ipu-bridge.o: in function `ipu_bridge_init':
ipu-bridge.c:(.text+0x9c9): undefined reference to `i2c_acpi_new_device_by_fwnode'

In general, drivers should not have to be built-in, so change the option
to a tristate with the corresponding dependency. This in turn opens a
new problem with the dependency, as the IPU bridge can be a loadable module
while the ipu3 driver itself is built-in, producing a new link failure:

86_64-linux-ld: drivers/media/pci/intel/ipu3/ipu3-cio2.o: in function `cio2_pci_probe':
ipu3-cio2.c:(.text+0x197e): undefined reference to `ipu_bridge_init'

In order to fix this, restore the old Kconfig option that controlled
the ipu bridge driver before it was split out, but make it select a
hidden symbol that now corresponds to the bridge driver.

When other drivers get added that share ipu-bridge, this should cover
all corner cases, and allow any combination of them to be built-in
or modular.

Link: https://lore.kernel.org/linux-media/20230727122331.2421453-1-arnd@kernel.org



Fixes: 881ca259 ("media: ipu3-cio2: rename cio2 bridge to ipu bridge and move out of ipu3")'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The CEC interrupt is only needed if userspace wants to monitor
the CEC pin for an unconfigured CEC device. That gives it the
most precise CEC pin debugging results.

This avoids a corner case where the interrupt is enabled for
a short period when the adapter is about to be configured.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Since the CEC pin framework now keeps track of the interrupt
and calls disable_irq when the kthread stops, there is no
longer any need for the cec-gpio driver to do this in the
free callback. So drop this code.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The CEC pin framework needs a bit more control over the interrupt
handling: make sure that the disable_irq op is called even if the
device node is unregistered, log the state of the interrupt in
debugfs, and disable the interrupt when the kernel thread is stopped.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Use IRQF_NO_AUTOEN rather than manually disabling the requested
interrupt.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Describe the new callbacks and clarify when the adap->lock
mutex is held or not.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The adap_configured() callback was called with the adap->lock mutex
held if the 'configured' argument was false, and without the adap->lock
mutex held if that argument was true.

That was very confusing, and so split this up in a adap_unconfigured()
callback and a high-level configured() callback.

This also makes it easier to understand when the mutex is held: all
low-level adap_* callbacks are called with the mutex held. All other
callbacks are called without that mutex held.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: f1b57164 ("media: cec: add optional adap_configured callback")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

A potential deadlock was found by Zheng Zhang with a local syzkaller
instance.

The problem is that when a non-blocking CEC transmit is canceled by calling
cec_data_cancel, that in turn can call the high-level received() driver
callback, which can call cec_transmit_msg() to transmit a new message.

The cec_data_cancel() function is called with the adap->lock mutex held,
and cec_transmit_msg() tries to take that same lock.

The root cause is that the received() callback can either be used to pass
on a received message (and then adap->lock is not held), or to report a
canceled transmit (and then adap->lock is held).

This is confusing, so create a new low-level adap_nb_transmit_canceled
callback that reports back that a non-blocking transmit was canceled.

And the received() callback is only called when a message is received,
as was the case before commit f9d0ecbf ("media: cec: correctly pass
on reply results") complicated matters.

Reported-by: Zheng Zhang <zheng.zhang@email.ucr.edu>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: f9d0ecbf ("media: cec: correctly pass on reply results")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Document that sub-device notifiers are now registered using
v4l2_async_subdev_nf_init(). No documentation is changed as it seems that
sub-device notifiers were not documented apart from kernel-doc comments.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Set the v4l2_device already in async notifier init, so struct device
related to it will be available before the notifier is registered. This
requires separating notifier initialisation into two functions, one that
takes v4l2_device as its argument, v4l2_async_nf_init and
v4l2_async_subdev_nf_init, for sub-device notifiers. Registering the
notifier will use a single function, v4l2_async_nf_register.

This is done in order to make struct device available earlier, during
construction of the async connections, for sensible debug prints.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Initialise V4L2 async notifier and parse DT for async sub-devices later,
just before registering the notifier. This way the device can be made
available to the V4L2 async framework from the notifier init time onwards.
A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Initialise the V4L2 async notifier after registering the V4L2 device, just
before parsing DT for async sub-devices. This way the device can be made
available to the V4L2 async framework from the notifier init time onwards.
A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Initialise the V4L2 async notifier after registering the V4L2 device, just
before parsing DT for async sub-devices. This way the device can be made
available to the V4L2 async framework from the notifier init time onwards.
A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Initialise V4L2 async notifier and parse DT for async sub-devices later,
just before registering the notifier. This way the device can be made
available to the V4L2 async framework from the notifier init time onwards.
A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Register V4L2 device before the async notifier.This way the device can be
made available to the V4L2 async framework from the notifier init time
onwards. A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Register V4L2 device before the async notifier. This way the device can be
made available to the V4L2 async framework from the notifier init time
onwards. A subsequent patch will add struct v4l2_device as an argument to
v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Register V4L2 device before initialising the notifier. This way the device
can be made available to the V4L2 async framework from the notifier init
time onwards. A subsequent patch will add struct v4l2_device as an
argument to v4l2_async_nf_init().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Fix and simplify error handling in pxa_camera probe, by moving devm_*()
functions early in the probe function and then tearing down what was set
up on error patch.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Return the two CSI-2 transmitters of adv748x to endpoint matching. This
should make the driver work again as expected.

Fixes: 1029939b ("media: v4l: async: Simplify async sub-device fwnode matching")
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Support matching V4L2 async sub-devices based on particular fwnode
endpoint. This makes it possible to instantiate multiple V4L2 sub-devices
based on given fwnode endpoints from a single device, based on driver
needs.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

When an async sub-device is registered, it used to be that the first one
of its connections were matched when found. Continue looking for matches
until a notifier no longer has any.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The list entry is initialised as a head in v4l2_async_register_subdev()
just before being added to the list. This isn't needed, drop the
initialisation.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

When the v4l2-async framework was introduced, the use case for it was to
connect a camera sensor with a parallel receiver. Both tended to be rather
simple devices with a single connection between them.

The framework has been since improved in multiple ways but there are
limitations that have remained, for instance the assumption an async
sub-device is connected towards a single notifier and via a single link
only.

This patch enables connecting a sub-device to one or more notifiers
simultaneously, with one or more connections per notifier. The notifier
information is moved from the sub-device to the connection and the
connections in sub-device are no longer a pointer but a linked list.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Add v4l2_async_connection_unique() function for obtaining a struct
v4l2_async_connection, typically allocated by drivers together with their
own information on an external sub-device.

The relation between connections and sub-devices still remains 1:1 but
this code becomes more complex when the relation soon changes.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

This patch re-arranges internal V4L2 async lists for preparation of
supporting multiple connections per sub-device as well as cleaning up used
lists.

The list of unbound V4L2 sub-devices shall be maintained for the purpose of
listing those sub-devices only, not for their bindin status. Also, the V4L2
async connections now have, instead of two list entries, a single list
entry in the notifier's list, be that either waiting or done lists, while
the notifier's asc_list is removed.

The one-to-one relation between a sub-device and a connection is still
maintained in this patch.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The connections are checked for duplicates already when the notifier is
registered. This is effectively a sanity check for driver (and possibly
obscure firmware) bugs. Don't do this when adding the connection.

Retain the int return type for now. It'll be needed very soon again.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Add labels for error handling instead of doing it all in individual cases.
Prepare for more functionality in this function.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Rename v4l2_async_subdev as v4l2_async_connection, in order to
differentiate between the sub-devices and their connections: one
sub-device can have many connections but the V4L2 async framework has so
far allowed just a single one. Connections in this context will later
translate into either MC ancillary or data links.

This patch prepares changing that relation by changing existing users of
v4l2_async_subdev to switch to v4l2_async_connection. Async sub-devices
themselves will not be needed anymore

Additionally, __v4l2_async_nf_add_subdev() has been renamed
__v4l2_async_nf_add_connection().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

V4L2 async sub-device matching originally used the device nodes only.
Endpoint nodes were taken into use instead as using the device nodes was
problematic for it was in some cases ambiguous which link might have been
in question.

There is however no need to use endpoint nodes on both sides, as the async
sub-device's fwnode can always be trivially obtained using
fwnode_graph_get_remote_endpoint() when needed while what counts is
whether or not the link is between two device nodes, i.e. the device nodes
match.

This will briefly break the adv748x driver but it will be fixed later in
the set, by patch "media: adv748x: Return to endpoint matching".

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The naming of list heads and list entries is confusing as they're named
similarly. Use _list for list head and _entry for list entries.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Pass only information required for sub-device matching to functions
checking whether the async sub-device already exists. Do the same for
debug message printing. This makes further changes to other aspects of
async sub-devices easier.

Accordingly, also perform further renames:

	asd_equal as v4l2_async_match_equal,
	v4l2_async_nf_has_async_subdev as v4l2_async_nf_has_async_match,
	__v4l2_async_nf_has_async_subdev as
		v4l2_async_nf_has_async_subdev_entry and
	v4l2_async_nf_asd_valid as v4l2_async_nf_match_valid.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The async match type is a struct field now, rename V4L2_ASYNC_MATCH_*
macros as V4L2_ASYNC_MATCH_TYPE_* instead.

This patch has been produced by:

git grep -l V4L2_ASYNC_MATCH_ -- drivers/media/ drivers/staging/media/ \
	include/ Documentation/|xargs perl -i -pe \
	's/V4L2_ASYNC_MATCH_\K/TYPE_/g'

so it must be correct.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Make V4L2 async match information a struct, making it easier to use it
elsewhere outside the scope of struct v4l2_async_subdev.

Also remove an obsolete comment --- none of these fields are supposed to
be touched by drivers.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The callers do pass a non-NULL asd to v4l2_async_nf_asd_valid() already.
There's no need for the NULL check here.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>