The Fujitsu M5MOLS sensor driver is using a reset GPIO number
passed from platform data.

No machine/board descriptor file in the kernel is using this so
let's replace it with a GPIO descriptor.

Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Heungjun Kim <riverful.kim@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

The noon010pc30 sensor driver is using legacy gpio numbers passed
through platform data and open coding reverse polarity on the
GPIOs used for reset and standby.

Nothing in the kernel defines any platform data for this driver
so we can just convert the driver to use GPIO descriptors and
requires that these specify the correct polarity instead.

Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Being able to call cleanup functions on objects that haven't been
initialized but whose memory has been zeroed simplifies error handling.
The media_entity_cleanup() function documentation doesn't tell whether
this is allowed or not, and inspection of its implementation doesn't
provide any clue as the function is currently empty. Update the
documentation to explicitly allow this usage pattern.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

The media_pipeline_start() function has two purposes: it constructs a
pipeline by recording the entities that are part of it, gathered from a
graph walk, and validate the media links. The pipeline pointer is stored
in the media_entity structure as part of this process, and the entity's
stream count is increased, to record that the entity is streaming.

When multiple video nodes are present in a pipeline,
media_pipeline_start() is typically called on all of them, with the same
pipeline pointer. This is taken into account in media_pipeline_start()
by skipping validation for entities that are already part of the
pipeline, while returning an error if an entity is part of a different
pipeline.

It turns out that this process is overly complicated. When
media_pipeline_start() is called for the first time, it constructs the
full pipeline, adding all entities and validating all the links.
Subsequent calls to media_pipeline_start() are then nearly no-ops, they
only increase the stream count on the pipeline and on all entities.

The media_entity stream_count field is used for two purposes: checking
if the entity is streaming, and detecting when a call to
media_pipeline_stop() balances needs to reset the entity pipe pointer to
NULL. The former can easily be replaced by a check of the pipe pointer.

Simplify media_pipeline_start() by avoiding the pipeline walk on all
calls but the first one, and drop the media_entity stream_count field.
media_pipeline_stop() is updated accordingly.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[Sakari Ailus: Drop redundant '!= NULL' as discussed]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Add a function to test if a pad is part of a pipeline currently
streaming, and use it through drivers to replace direct access to the
stream_count field. This will help reworking pipeline start/stop without
disturbing drivers.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

There are many CSI-2-related drivers in the media subsystem that come
with their own macros to handle the CSI-2 data types (or just hardcode
the numerical values). Provide a shared header with definitions for
those data types that driver can use.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

MIPI CSI-2 continuous and non-continuous clock modes are mutually
exclusive. Drop the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag and use
V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK only.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The V4L2_MBUS_CSI2_CHANNEL_* flags are a legacy API. Only
V4L2_MBUS_CSI2_CHANNEL_0 is used, set in a single driver, and never
read. Drop those flags. Virtual channel information should be conveyed
through frame descriptors instead.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The V4L2_MBUS_CSI2_*_LANE flags are a legacy API and are unused. Drop
them.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

The media bus configuration is specified through a set of flags, some of
which being mutually exclusive. This doesn't scale to express more
complex configurations. Improve the API by replacing the single flags
field in v4l2_mbus_config by a union of v4l2_mbus_config_* structures.
The flags themselves are still used in those structures, so they are
kept here. Drivers are however updated to use structure fields instead
of flags when already possible.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>