staging: media: tegra-video: Kconfig: allow TPG only on Tegra210

We are about to add support for the Tegra20 parallel video capture, which
has no TPG. In preparation for that, limit the VIDEO_TEGRA_TPG option to
Tegra210 which is the only implementation currently provided by this
driver.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: Kconfig: cleanup VIDEO_DEV dependencies

media Kconfig has two entries associated to V4L API:
VIDEO_DEV and VIDEO_V4L2.

On Kernel 2.6.x, there were two V4L APIs, each one with its own flag.
VIDEO_DEV were meant to:
1) enable Video4Linux and make its Kconfig options to appear;
2) it makes the Kernel build the V4L core.

while VIDEO_V4L2 where used to distinguish between drivers that
implement the newer API and drivers that implemented the former one.

With time, such meaning changed, specially after the removal of
all V4L version 1 drivers.

At the current implementation, VIDEO_DEV only does (1): it enables
the media options related to V4L, that now has:

menu "Video4Linux options"
visible if VIDEO_DEV

source "drivers/media/v4l2-core/Kconfig"
endmenu

but it doesn't affect anymore the V4L core drivers.

The rationale is that the V4L2 core has a "soft" dependency
at the I2C bus, and now requires to select a number of other
Kconfig options:

config VIDEO_V4L2
tristate
depends on (I2C || I2C=n) && VIDEO_DEV
select RATIONAL
select VIDEOBUF2_V4L2 if VIDEOBUF2_CORE
default (I2C || I2C=n) && VIDEO_DEV

In the past, merging them would be tricky, but it seems that it is now
possible to merge those symbols, in order to simplify V4L dependencies.

Let's keep VIDEO_DEV, as this one is used on some make *defconfig
configurations.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> # for meson-vdec & meson-ge2d
Acked-by: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

media: tegra-video: Add support for external sensor capture

This patch adds support to capture from the external sensor
based on device graph in the device tree.

Driver walks through the device graph to create media links
between the entities and registers and unregisters video devices
when the corresponding sub-devices are bound and unbound.

Channel formats are enumerated based on available formats from
the sensor and the corresponding matched formats from the Tegra
supported video formats list.

Each Tegra CSI instance can be configured as 4-lane or 2-lane
based on supported lane configuration from the sensor through
the device tree.

Currently this driver supports V4L2 video node centric only.

[hverkuil: changed video_unregister_device to vb2_video_unregister_device]

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: tegra-video: Enable TPG based on kernel config

Tegra internal TPG mode is only for Tegra vi and csi testing
without a real sensor and driver should default support real
sensor.

So, This patch adds CONFIG_VIDEO_TEGRA_TPG and enables Tegra
internal TPG mode only when this config is selected.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

staging: tegra-video: fix V4L2 dependency

Rather than using a dependency on VIDEO_V4L2, this driver uses
"select", which fails when other dependencies are missing:

WARNING: unmet direct dependencies detected for VIDEO_V4L2
Depends on [n]: MEDIA_SUPPORT [=y] && (I2C [=y] || I2C [=y]=n) && VIDEO_DEV [=n]
Selected by [y]:
- VIDEO_TEGRA [=y] && STAGING [=y] && STAGING_MEDIA [=y] && MEDIA_SUPPORT [=y] && TEGRA_HOST1X [=y]
(plus an endless stream of link errors for other drivers that
depend on VIDEO_V4L2 but are now lacking their dependencies)

Link: https://lore.kernel.org/r/20200527221327.3339232-1-arnd@arndb.de
Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

media: tegra-video: Do not enable COMPILE_TEST

The symbols exported when TEGRA_HOST1X is selected don't have dummies
that could serve as stubs for COMPILE_TEST, so a hard dependency on the
TEGRA_HOST1X symbol is needed.

Suggested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thierry Reding <treding@nvidia.com>

media: tegra-video: Add Tegra210 Video input driver

Tegra210 contains a powerful Video Input (VI) hardware controller
which can support up to 6 MIPI CSI camera sensors.

Each Tegra CSI port can be one-to-one mapped to VI channel and can
capture from an external camera sensor connected to CSI or from
built-in test pattern generator.

Tegra210 supports built-in test pattern generator from CSI to VI.

This patch adds a V4L2 capture driver with a media interface for
Tegra210 built-in CSI to VI test pattern generator.

This patch includes TPG support only and all the video pipeline
configuration happens through the video device node.

Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Thierry Reding <treding@nvidia.com>