media: staging: media: omap4iss: Added SPDX license identifiers

Added missing SPDX license identifiers to all files of the omap4iss
driver.

Most files already have license texts which clearly state them to be
licensed under GPL 2.0 or later. SPDX identifiers were added accordingly.

Some files do not have any license text. SPDX identifiers for GPL 2.0
were added to them, in accordance with the default license of the
kernel.

Signed-off-by: Daniel Graefe <daniel.graefe@fau.de>
Signed-off-by: Roman Sommer <roman.sommer@fau.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

[media] staging: omap4iss: remove pads prefix from *_create_pads_links()

The functions that create ISS internal and external entities links are
called *_create_pads_links() but the "pads" prefix is redundant since
the driver doesn't handle any other kind of link so it can be removed.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] staging: omap4iss: separate links creation from entities init

The omap4iss driver initializes the entities and creates the pads links
before the entities are registered with the media device. This does not
work now that object IDs are used to create links so the media_device
has to be set.

Split out the pads links creation from the entity initialization so are
made after the entities registration.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

staging: media: omap4iss: Replaces bit shift on 1 with BIT Macro

This patch fixes some of the checkpatch issue:

CHECK: Prefer using the BIT macro

Signed-off-by: Amarjargal Gundjalam <amarjargal.gundjalam@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[media] v4l: omap4iss: csi2: Perform real frame number propagation

Compute the pipeline frame number from the frame number sent by the
sensor instead of incrementing the frame number in software. This
improves dropped frames detection.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] v4l: omap4iss: csi2: Replace manual if statement with a subclk field

Instead of manually checking whether the CSI2 module is CSI2a or CSI2b
in order to select the right subclock to enable/disable, add a subclk
field to the iss_csi2 structure, initialize it with the corresponding
subclock value and use it at runtime.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

[media] v4l: omap4iss: csi: Create and use register access functions

Replace the direct readl/writel calls with helper functions.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

[media] v4l: omap4iss: Add support for OMAP4 camera interface - CSI receivers

This adds a very simplistic driver to utilize the CSI2A interface inside
the ISS subsystem in OMAP4, and dump the data to memory.
Check Documentation/video4linux/omap4_camera.txt for details.
This commit adds CSI receivers support.

Signed-off-by: Sergio Aguirre <sergio.a.aguirre@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>