media: vidtv: remove unused field from 'struct vidtv_mpeg_ts'

Commit 3d1387b3b8f6 ("media: vidtv: fix some warnings") replaced
the unused flexible array member at the end of struct vidtv_mpeg_ts
with a pointer. This broke the 188-byte alignment since the struct
no longer was 4 bytes in size.

Fix this by removing this field entirely.

Fixes: 3d1387b3b8f6 ("media: vidtv: fix some warnings")
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

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.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: 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: 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>