media: vidtv: fix some warnings

As reported by sparse:

drivers/media/test-drivers/vidtv/vidtv_ts.h:47:47: warning: array of flexible structures
drivers/media/test-drivers/vidtv/vidtv_channel.c:458:54: warning: incorrect type in argument 3 (different base types)
drivers/media/test-drivers/vidtv/vidtv_channel.c:458:54: expected unsigned short [usertype] service_id
drivers/media/test-drivers/vidtv/vidtv_channel.c:458:54: got restricted __be16 [usertype] service_id
drivers/media/test-drivers/vidtv/vidtv_s302m.c:471 vidtv_s302m_encoder_init() warn: possible memory leak of 'e'

Address such warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: fix kernel-doc markups

Some functions has a different name between their prototypes
and the corresponding kernel-doc markups.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv.rst: add kernel-doc markups

Fix existing issues at the kernel-doc markups and add them to
the vidtv.rst file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: simplify EIT write function

- pass struct vidtv_psi_eit_write_args as a pointer;
- avoid initializing struct fields multiple times.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: simplify NIT write function

- pass struct vidtv_psi_nit_write_args as a pointer;
- avoid initializing struct fields multiple times.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: simplify SDT write function

- pass struct vidtv_psi_sdt_write_args as a pointer;
- avoid initializing struct fields multiple times.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: cleanup PMT write table function

- Pass struct vidtv_psi_pmt_write_args as a pointer;
- Avoid initializing structs multiple times.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: cleanup PAT write function

Avoid initializing the structs multiple times and pass the
PAT struct as a pointer, instead of a var.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: fix service_id at SDT table

The service_id there should be equal to the one used
on other tables, otherwise, EIT entries won't be valid.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: fix service type

As the service currently broadcasts just audio, change the
service type to reflect that.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: add a PID entry for the NIT table

On normal TS streams, the NIT table has its own entry at PAT,
but not at PMT.

While here, properly handle alloc problems when creating
PMT entries.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: properly fill EIT service_id

The EIT header ID field should not contain the network ID, but,
instead, the service_id of the program described at EIT.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: reorganize includes

- Place the includes on alphabetical order;
- get rid of asm/byteorder.h;
- add bug.h at vidtv_s302m.c, as it is needed by
inux/fixp-arith.h

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: psi: Implement an Event Information Table (EIT)

Implement an Event Information Table (EIT) as per EN 300 468
5.2.4.

The EIT provides information in chronological order regarding
the events contained within each service.

For now only present event information is supported.

[mchehab+huawei@kernel.org: removed an extra blank line]
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: psi: add a Network Information Table (NIT)

Add a Network Information Table (NIT) as specified in ETSI EN 300 468.

This table conveys information relating to the physical organization of
the multiplexes carried via a given network and the characteristics of
the network itself.

It is conveyed in the output of vidtv as packets with TS PID of 0x0010

[mchehab+huawei@kernel.org: removed an extra blank line]
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: remove more ENDIAN_BITFIELD nonsense

Changeset 870e350d4e39 ("media: vidtv: get rid of ENDIAN_BITFIELD nonsense")
was incomplete. There are still some wrong endannes logic at
the driver. Get rid of them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: get rid of ENDIAN_BITFIELD nonsense

The two places where ENDIAN_BITFIELD is used is for a single
8-bits integer. No need to correct endiannes on such cases.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

media: vidtv: add a bridge driver

Digital TV devices consist of several independent hardware components
which are controlled by different drivers.
Each media device is controlled by a group of cooperating drivers with the
bridge driver as the main driver.

This patch adds a bridge driver for the Virtual Digital TV driver [vidtv].

The bridge driver binds to the other drivers, that is, vidtv_tuner and
vidtv_demod and implements the digital demux logic, providing userspace
with a MPEG Transport Stream.

The MPEG related code is split in the following way:

- vidtv_ts: code to work with MPEG TS packets, such as TS headers,
adaptation fields, PCR packets and NULL packets.

- vidtv_psi: this is the PSI generator.
PSI packets contain general information about a MPEG Transport Stream.
A PSI generator is needed so userspace apps can retrieve information
about the Transport Stream and eventually tune into a (dummy) channel.

Because the generator is implemented in a separate file, it can be
reused elsewhere in the media subsystem.

Currently vidtv supports working with 3 PSI tables:
PAT, PMT and SDT.

- vidtv_pes: implements the PES logic to convert encoder data into
MPEG TS packets. These can then be fed into a TS multiplexer and
eventually into userspace.

- vidtv_s302m: implements a S302M encoder to make it possible to
insert PCM audio data in the generated MPEG Transport Stream.

This shall enable passing an audio signal into userspace so it can be
decoded and played by media software.

- vidtv_channels: Implements a 'channel' abstraction

When vidtv boots, it will create some hardcoded channels:

Their services will be concatenated to populate the SDT.
Their programs will be concatenated to populate the PAT
For each program in the PAT, a PMT section will be created
The PMT section for a channel will be assigned its streams.
Every stream will have its corresponding encoder polled to produce TS
packets
These packets may be interleaved by the mux and then delivered to the
bridge

- vidtv_mux - Implements a MPEG TS mux, loosely based on the ffmpeg
implementation

The multiplexer is responsible for polling encoders,
interleaving packets, padding the resulting stream with NULL packets if
necessary and then delivering the resulting TS packets to the bridge
driver so it can feed the demux.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>