linux.git/drivers/media/test-drivers/vimc, branch v6.7

media: Zero-initialize all structures passed to subdev pad operations

2023-04-12T07:46:06+00:00

Several drivers call subdev pad operations, passing structures that are
not fully zeroed. While the drivers initialize the fields they care
about explicitly, this results in reserved fields having uninitialized
values. Future kernel API changes that make use of those fields thus
risk breaking proper driver operation in ways that could be hard to
detect.

To avoid this, make the code more robust by zero-initializing all the
structures passed to subdev pad operation. Maintain a consistent coding
style by preferring designated initializers (which zero-initialize all
the fields that are not specified) over memset() where possible, and
make variable declarations local to inner scopes where applicable. One
notable exception to this rule is in the ipu3 driver, where a memset()
is needed as the structure is not a local variable but a function
parameter provided by the caller.

Not all fields of those structures can be initialized when declaring the
variables, as the values for those fields are computed later in the
code. Initialize the 'which' field in all cases, and other fields when
the variable declaration is so close to the v4l2_subdev_call() call that
it keeps all the context easily visible when reading the code, to avoid
hindering readability.

Signed-off-by: Laurent Pinchart 
Acked-by: Shuah Khan  # For vimc
Reviewed-by: Lad Prabhakar  # For am437x
Acked-by: Sakari Ailus 
Reviewed-by: Tomi Valkeinen 
Reviewed-by: Kieran Bingham 
Reviewed-by: Philipp Zabel  # For drivers/staging/media/imx/
Signed-off-by: Hans Verkuil

media: vimc-core: Convert to platform remove callback returning void

2023-04-11T14:59:21+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König 
Signed-off-by: Hans Verkuil

media: vimc: Fix wrong function called when vimc_init() fails

2022-11-25T07:26:16+00:00

In vimc_init(), when platform_driver_register(&vimc_pdrv) fails,
platform_driver_unregister(&vimc_pdrv) is wrongly called rather than
platform_device_unregister(&vimc_pdev), which causes kernel warning:

 Unexpected driver unregister!
 WARNING: CPU: 1 PID: 14517 at drivers/base/driver.c:270 driver_unregister+0x8f/0xb0
 RIP: 0010:driver_unregister+0x8f/0xb0
 Call Trace:
  
  vimc_init+0x7d/0x1000 [vimc]
  do_one_initcall+0xd0/0x4e0
  do_init_module+0x1cf/0x6b0
  load_module+0x65c2/0x7820

Fixes: 4a29b7090749 ("[media] vimc: Subdevices as modules")
Signed-off-by: Chen Zhongjin 
Signed-off-by: Shuah Khan 
Signed-off-by: Mauro Carvalho Chehab

media: drivers: use video device pipeline start/stop

2022-09-24T07:14:20+00:00

Convert the media drivers to use video device based pipeline start/stop
where possible.

Signed-off-by: Tomi Valkeinen 
Reviewed-by: Laurent Pinchart 
Signed-off-by: Sakari Ailus 
Signed-off-by: Mauro Carvalho Chehab

media: vimc: wrong pointer is used with PTR_ERR

2022-07-27T18:24:56+00:00

Fix smatch warning:

drivers/media/test-drivers/vimc/vimc-core.c:214 vimc_create_links() warn: passing a valid pointer to 'PTR_ERR'

Signed-off-by: Hans Verkuil 
Reviewed-by: Kieran Bingham 
Signed-off-by: Mauro Carvalho Chehab

media: mc-entity: Rename media_entity_remote_pad() to media_pad_remote_pad_first()

2022-07-17T10:21:35+00:00

The media_entity_remote_pad() is misnamed, as it operates on a pad and
not an entity. Rename it to media_pad_remote_pad_first() to clarify its
behaviour.

Signed-off-by: Laurent Pinchart 
Reviewed-by: Hans Verkuil 
Acked-by: Sakari Ailus 
Signed-off-by: Mauro Carvalho Chehab

media: vimc: use data link entities enum to index the ent_config array

2022-07-15T13:43:55+00:00

Future additions to the ent_config[] could break the association between
the index of the struct vimc_ent_config entries in the ent_config[] array,
and the index defined by the enum proposed in the previous patch. Using
designated initializers solves this by linking the 2 together clearly in
code and prevents the array not reflecting the enum. There is no
functional change intended.

Suggested-by: Kieran Bingham 
Signed-off-by: Daniel Oakley 
Signed-off-by: Shuah Khan 
Signed-off-by: Mauro Carvalho Chehab

media: vimc: enumerate data link entities for clarity

2022-07-15T13:43:32+00:00

The data_links array was hard to read and understand. By implementing
enumerated vimc data link entities, clarity has been improved when
defining data_links. This therefore should help new programmers to
understand the codebase better. There is no functional change intended.

Suggested-by: Kieran Bingham 
Signed-off-by: Daniel Oakley 
Signed-off-by: Shuah Khan 
Signed-off-by: Mauro Carvalho Chehab

media: vimc: expand the names of vimc entity types

2022-07-15T13:42:14+00:00

When introducing the lens controller, it became apparent that the vimc
entity type names were hard to understand, e.g. vimc_len_type refers to the
lens. The names of the vimc entity types have been expanded to make the
code easier to understand. There is no functional change intended.

Suggested-by: Kieran Bingham 
Signed-off-by: Daniel Oakley 
Signed-off-by: Shuah Khan 
Signed-off-by: Mauro Carvalho Chehab

media: vimc: add ancillary lens

2022-07-15T13:40:09+00:00

Add lens to vimc driver and link them with sensors using ancillary links.
Provides an example of ancillary link usage.The lens supports
FOCUS_ABSOLUTE control.

Test example: With default vimc topology
> media-ctl -p
Media controller API version 5.18.0
...
- entity 28: Lens A (0 pad, 0 link)
             type V4L2 subdev subtype Lens flags 0
             device node name /dev/v4l-subdev6
- entity 29: Lens B (0 pad, 0 link)
             type V4L2 subdev subtype Lens flags 0
             device node name /dev/v4l-subdev7
> v4l2-ctl -d /dev/v4l-subdev7 -C focus_absolute
focus_absolute: 0

Reviewed-by: Kieran Bingham 
Signed-off-by: Yunke Cao 
Signed-off-by: Shuah Khan 
Signed-off-by: Mauro Carvalho Chehab