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>

1 files changed, 552 insertions, 0 deletions

diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.c b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
new file mode 100644
index 000000000000..3b20a26d8721
--- /dev/null
+++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
@@ -0,0 +1,552 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Vidtv serves as a reference DVB driver and helps validate the existing APIs
+ * in the media subsystem. It can also aid developers working on userspace
+ * applications.
+ *
+ * This file contains the code for an AES3 (also known as AES/EBU) encoder.
+ * It is based on EBU Tech 3250 and SMPTE 302M technical documents.
+ *
+ * This encoder currently supports 16bit AES3 subframes using 16bit signed
+ * integers.
+ *
+ * Note: AU stands for Access Unit, and AAU stands for Audio Access Unit
+ *
+ * Copyright (C) 2020 Daniel W. S. Almeida
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s, %d: " fmt, __func__, __LINE__
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/vmalloc.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/printk.h>
+#include <linux/ratelimit.h>
+#include <linux/math64.h>
+#include <asm/byteorder.h>
+
+#include "vidtv_s302m.h"
+#include "vidtv_encoder.h"
+#include "vidtv_common.h"
+
+#define S302M_SAMPLING_RATE_HZ 48000
+#define PES_PRIVATE_STREAM_1 0xbd  /* PES: private_stream_1 */
+#define S302M_BLOCK_SZ 192
+#define S302M_SIN_LUT_NUM_ELEM 1024
+
+static const u8 reverse[256] = {
+	/* from ffmpeg */
+	0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0,
+	0x30, 0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
+	0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4,
+	0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
+	0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC,
+	0x3C, 0xBC, 0x7C, 0xFC, 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
+	0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, 0x0A, 0x8A, 0x4A, 0xCA,
+	0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
+	0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6,
+	0x36, 0xB6, 0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
+	0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81, 0x41, 0xC1,
+	0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
+	0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9,
+	0x39, 0xB9, 0x79, 0xF9, 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
+	0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD,
+	0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
+	0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3,
+	0x33, 0xB3, 0x73, 0xF3, 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
+	0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7,
+	0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
+	0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF,
+	0x3F, 0xBF, 0x7F, 0xFF,
+};
+
+/*
+ * This buffer contains PCM audio samples of a sine wave, compatible with
+ * S302. If this is used as a source, a userspace media application should be able
+ * to play it.
+ */
+static u16 s302m_sin_lut[S302M_SIN_LUT_NUM_ELEM] = {
+	0x8000, 0x80c9, 0x8192, 0x825b, 0x8324, 0x83ed, 0x84b6, 0x857e,
+	0x8647, 0x8710, 0x87d9, 0x88a1, 0x896a, 0x8a32, 0x8afb, 0x8bc3,
+	0x8c8b, 0x8d53, 0x8e1b, 0x8ee3, 0x8fab, 0x9072, 0x9139, 0x9201,
+	0x92c7, 0x938e, 0x9455, 0x951b, 0x95e1, 0x96a7, 0x976d, 0x9833,
+	0x98f8, 0x99bd, 0x9a82, 0x9b47, 0x9c0b, 0x9ccf, 0x9d93, 0x9e56,
+	0x9f19, 0x9fdc, 0xa09f, 0xa161, 0xa223, 0xa2e5, 0xa3a6, 0xa467,
+	0xa527, 0xa5e8, 0xa6a7, 0xa767, 0xa826, 0xa8e5, 0xa9a3, 0xaa61,
+	0xab1f, 0xabdc, 0xac98, 0xad55, 0xae10, 0xaecc, 0xaf87, 0xb041,
+	0xb0fb, 0xb1b5, 0xb26e, 0xb326, 0xb3de, 0xb496, 0xb54d, 0xb603,
+	0xb6b9, 0xb76f, 0xb824, 0xb8d8, 0xb98c, 0xba3f, 0xbaf2, 0xbba4,
+	0xbc56, 0xbd07, 0xbdb7, 0xbe67, 0xbf17, 0xbfc5, 0xc073, 0xc121,
+	0xc1cd, 0xc279, 0xc325, 0xc3d0, 0xc47a, 0xc524, 0xc5cc, 0xc675,
+	0xc71c, 0xc7c3, 0xc869, 0xc90f, 0xc9b3, 0xca57, 0xcafb, 0xcb9d,
+	0xcc3f, 0xcce0, 0xcd81, 0xce20, 0xcebf, 0xcf5d, 0xcffb, 0xd097,
+	0xd133, 0xd1ce, 0xd268, 0xd302, 0xd39a, 0xd432, 0xd4c9, 0xd55f,
+	0xd5f5, 0xd689, 0xd71d, 0xd7b0, 0xd842, 0xd8d3, 0xd964, 0xd9f3,
+	0xda82, 0xdb0f, 0xdb9c, 0xdc28, 0xdcb3, 0xdd3d, 0xddc7, 0xde4f,
+	0xded7, 0xdf5d, 0xdfe3, 0xe068, 0xe0eb, 0xe16e, 0xe1f0, 0xe271,
+	0xe2f1, 0xe370, 0xe3ee, 0xe46b, 0xe4e8, 0xe563, 0xe5dd, 0xe656,
+	0xe6cf, 0xe746, 0xe7bc, 0xe831, 0xe8a6, 0xe919, 0xe98b, 0xe9fc,
+	0xea6d, 0xeadc, 0xeb4a, 0xebb7, 0xec23, 0xec8e, 0xecf8, 0xed61,
+	0xedc9, 0xee30, 0xee96, 0xeefa, 0xef5e, 0xefc1, 0xf022, 0xf083,
+	0xf0e2, 0xf140, 0xf19d, 0xf1f9, 0xf254, 0xf2ae, 0xf307, 0xf35e,
+	0xf3b5, 0xf40a, 0xf45f, 0xf4b2, 0xf504, 0xf555, 0xf5a5, 0xf5f3,
+	0xf641, 0xf68d, 0xf6d8, 0xf722, 0xf76b, 0xf7b3, 0xf7fa, 0xf83f,
+	0xf884, 0xf8c7, 0xf909, 0xf94a, 0xf989, 0xf9c8, 0xfa05, 0xfa41,
+	0xfa7c, 0xfab6, 0xfaee, 0xfb26, 0xfb5c, 0xfb91, 0xfbc5, 0xfbf8,
+	0xfc29, 0xfc59, 0xfc88, 0xfcb6, 0xfce3, 0xfd0e, 0xfd39, 0xfd62,
+	0xfd89, 0xfdb0, 0xfdd5, 0xfdfa, 0xfe1d, 0xfe3e, 0xfe5f, 0xfe7e,
+	0xfe9c, 0xfeb9, 0xfed5, 0xfeef, 0xff09, 0xff21, 0xff37, 0xff4d,
+	0xff61, 0xff74, 0xff86, 0xff97, 0xffa6, 0xffb4, 0xffc1, 0xffcd,
+	0xffd8, 0xffe1, 0xffe9, 0xfff0, 0xfff5, 0xfff9, 0xfffd, 0xfffe,
+	0xffff, 0xfffe, 0xfffd, 0xfff9, 0xfff5, 0xfff0, 0xffe9, 0xffe1,
+	0xffd8, 0xffcd, 0xffc1, 0xffb4, 0xffa6, 0xff97, 0xff86, 0xff74,
+	0xff61, 0xff4d, 0xff37, 0xff21, 0xff09, 0xfeef, 0xfed5, 0xfeb9,
+	0xfe9c, 0xfe7e, 0xfe5f, 0xfe3e, 0xfe1d, 0xfdfa, 0xfdd5, 0xfdb0,
+	0xfd89, 0xfd62, 0xfd39, 0xfd0e, 0xfce3, 0xfcb6, 0xfc88, 0xfc59,
+	0xfc29, 0xfbf8, 0xfbc5, 0xfb91, 0xfb5c, 0xfb26, 0xfaee, 0xfab6,
+	0xfa7c, 0xfa41, 0xfa05, 0xf9c8, 0xf989, 0xf94a, 0xf909, 0xf8c7,
+	0xf884, 0xf83f, 0xf7fa, 0xf7b3, 0xf76b, 0xf722, 0xf6d8, 0xf68d,
+	0xf641, 0xf5f3, 0xf5a5, 0xf555, 0xf504, 0xf4b2, 0xf45f, 0xf40a,
+	0xf3b5, 0xf35e, 0xf307, 0xf2ae, 0xf254, 0xf1f9, 0xf19d, 0xf140,
+	0xf0e2, 0xf083, 0xf022, 0xefc1, 0xef5e, 0xeefa, 0xee96, 0xee30,
+	0xedc9, 0xed61, 0xecf8, 0xec8e, 0xec23, 0xebb7, 0xeb4a, 0xeadc,
+	0xea6d, 0xe9fc, 0xe98b, 0xe919, 0xe8a6, 0xe831, 0xe7bc, 0xe746,
+	0xe6cf, 0xe656, 0xe5dd, 0xe563, 0xe4e8, 0xe46b, 0xe3ee, 0xe370,
+	0xe2f1, 0xe271, 0xe1f0, 0xe16e, 0xe0eb, 0xe068, 0xdfe3, 0xdf5d,
+	0xded7, 0xde4f, 0xddc7, 0xdd3d, 0xdcb3, 0xdc28, 0xdb9c, 0xdb0f,
+	0xda82, 0xd9f3, 0xd964, 0xd8d3, 0xd842, 0xd7b0, 0xd71d, 0xd689,
+	0xd5f5, 0xd55f, 0xd4c9, 0xd432, 0xd39a, 0xd302, 0xd268, 0xd1ce,
+	0xd133, 0xd097, 0xcffb, 0xcf5d, 0xcebf, 0xce20, 0xcd81, 0xcce0,
+	0xcc3f, 0xcb9d, 0xcafb, 0xca57, 0xc9b3, 0xc90f, 0xc869, 0xc7c3,
+	0xc71c, 0xc675, 0xc5cc, 0xc524, 0xc47a, 0xc3d0, 0xc325, 0xc279,
+	0xc1cd, 0xc121, 0xc073, 0xbfc5, 0xbf17, 0xbe67, 0xbdb7, 0xbd07,
+	0xbc56, 0xbba4, 0xbaf2, 0xba3f, 0xb98c, 0xb8d8, 0xb824, 0xb76f,
+	0xb6b9, 0xb603, 0xb54d, 0xb496, 0xb3de, 0xb326, 0xb26e, 0xb1b5,
+	0xb0fb, 0xb041, 0xaf87, 0xaecc, 0xae10, 0xad55, 0xac98, 0xabdc,
+	0xab1f, 0xaa61, 0xa9a3, 0xa8e5, 0xa826, 0xa767, 0xa6a7, 0xa5e8,
+	0xa527, 0xa467, 0xa3a6, 0xa2e5, 0xa223, 0xa161, 0xa09f, 0x9fdc,
+	0x9f19, 0x9e56, 0x9d93, 0x9ccf, 0x9c0b, 0x9b47, 0x9a82, 0x99bd,
+	0x98f8, 0x9833, 0x976d, 0x96a7, 0x95e1, 0x951b, 0x9455, 0x938e,
+	0x92c7, 0x9201, 0x9139, 0x9072, 0x8fab, 0x8ee3, 0x8e1b, 0x8d53,
+	0x8c8b, 0x8bc3, 0x8afb, 0x8a32, 0x896a, 0x88a1, 0x87d9, 0x8710,
+	0x8647, 0x857e, 0x84b6, 0x83ed, 0x8324, 0x825b, 0x8192, 0x80c9,
+	0x8000, 0x7f36, 0x7e6d, 0x7da4, 0x7cdb, 0x7c12, 0x7b49, 0x7a81,
+	0x79b8, 0x78ef, 0x7826, 0x775e, 0x7695, 0x75cd, 0x7504, 0x743c,
+	0x7374, 0x72ac, 0x71e4, 0x711c, 0x7054, 0x6f8d, 0x6ec6, 0x6dfe,
+	0x6d38, 0x6c71, 0x6baa, 0x6ae4, 0x6a1e, 0x6958, 0x6892, 0x67cc,
+	0x6707, 0x6642, 0x657d, 0x64b8, 0x63f4, 0x6330, 0x626c, 0x61a9,
+	0x60e6, 0x6023, 0x5f60, 0x5e9e, 0x5ddc, 0x5d1a, 0x5c59, 0x5b98,
+	0x5ad8, 0x5a17, 0x5958, 0x5898, 0x57d9, 0x571a, 0x565c, 0x559e,
+	0x54e0, 0x5423, 0x5367, 0x52aa, 0x51ef, 0x5133, 0x5078, 0x4fbe,
+	0x4f04, 0x4e4a, 0x4d91, 0x4cd9, 0x4c21, 0x4b69, 0x4ab2, 0x49fc,
+	0x4946, 0x4890, 0x47db, 0x4727, 0x4673, 0x45c0, 0x450d, 0x445b,
+	0x43a9, 0x42f8, 0x4248, 0x4198, 0x40e8, 0x403a, 0x3f8c, 0x3ede,
+	0x3e32, 0x3d86, 0x3cda, 0x3c2f, 0x3b85, 0x3adb, 0x3a33, 0x398a,
+	0x38e3, 0x383c, 0x3796, 0x36f0, 0x364c, 0x35a8, 0x3504, 0x3462,
+	0x33c0, 0x331f, 0x327e, 0x31df, 0x3140, 0x30a2, 0x3004, 0x2f68,
+	0x2ecc, 0x2e31, 0x2d97, 0x2cfd, 0x2c65, 0x2bcd, 0x2b36, 0x2aa0,
+	0x2a0a, 0x2976, 0x28e2, 0x284f, 0x27bd, 0x272c, 0x269b, 0x260c,
+	0x257d, 0x24f0, 0x2463, 0x23d7, 0x234c, 0x22c2, 0x2238, 0x21b0,
+	0x2128, 0x20a2, 0x201c, 0x1f97, 0x1f14, 0x1e91, 0x1e0f, 0x1d8e,
+	0x1d0e, 0x1c8f, 0x1c11, 0x1b94, 0x1b17, 0x1a9c, 0x1a22, 0x19a9,
+	0x1930, 0x18b9, 0x1843, 0x17ce, 0x1759, 0x16e6, 0x1674, 0x1603,
+	0x1592, 0x1523, 0x14b5, 0x1448, 0x13dc, 0x1371, 0x1307, 0x129e,
+	0x1236, 0x11cf, 0x1169, 0x1105, 0x10a1, 0x103e, 0xfdd, 0xf7c,
+	0xf1d, 0xebf, 0xe62, 0xe06, 0xdab, 0xd51, 0xcf8, 0xca1,
+	0xc4a, 0xbf5, 0xba0, 0xb4d, 0xafb, 0xaaa, 0xa5a, 0xa0c,
+	0x9be, 0x972, 0x927, 0x8dd, 0x894, 0x84c, 0x805, 0x7c0,
+	0x77b, 0x738, 0x6f6, 0x6b5, 0x676, 0x637, 0x5fa, 0x5be,
+	0x583, 0x549, 0x511, 0x4d9, 0x4a3, 0x46e, 0x43a, 0x407,
+	0x3d6, 0x3a6, 0x377, 0x349, 0x31c, 0x2f1, 0x2c6, 0x29d,
+	0x276, 0x24f, 0x22a, 0x205, 0x1e2, 0x1c1, 0x1a0, 0x181,
+	0x163, 0x146, 0x12a, 0x110, 0xf6, 0xde, 0xc8, 0xb2,
+	0x9e, 0x8b, 0x79, 0x68, 0x59, 0x4b, 0x3e, 0x32,
+	0x27, 0x1e, 0x16, 0xf, 0xa, 0x6, 0x2, 0x1,
+	0x0, 0x1, 0x2, 0x6, 0xa, 0xf, 0x16, 0x1e,
+	0x27, 0x32, 0x3e, 0x4b, 0x59, 0x68, 0x79, 0x8b,
+	0x9e, 0xb2, 0xc8, 0xde, 0xf6, 0x110, 0x12a, 0x146,
+	0x163, 0x181, 0x1a0, 0x1c1, 0x1e2, 0x205, 0x22a, 0x24f,
+	0x276, 0x29d, 0x2c6, 0x2f1, 0x31c, 0x349, 0x377, 0x3a6,
+	0x3d6, 0x407, 0x43a, 0x46e, 0x4a3, 0x4d9, 0x511, 0x549,
+	0x583, 0x5be, 0x5fa, 0x637, 0x676, 0x6b5, 0x6f6, 0x738,
+	0x77b, 0x7c0, 0x805, 0x84c, 0x894, 0x8dd, 0x927, 0x972,
+	0x9be, 0xa0c, 0xa5a, 0xaaa, 0xafb, 0xb4d, 0xba0, 0xbf5,
+	0xc4a, 0xca1, 0xcf8, 0xd51, 0xdab, 0xe06, 0xe62, 0xebf,
+	0xf1d, 0xf7c, 0xfdd, 0x103e, 0x10a1, 0x1105, 0x1169, 0x11cf,
+	0x1236, 0x129e, 0x1307, 0x1371, 0x13dc, 0x1448, 0x14b5, 0x1523,
+	0x1592, 0x1603, 0x1674, 0x16e6, 0x1759, 0x17ce, 0x1843, 0x18b9,
+	0x1930, 0x19a9, 0x1a22, 0x1a9c, 0x1b17, 0x1b94, 0x1c11, 0x1c8f,
+	0x1d0e, 0x1d8e, 0x1e0f, 0x1e91, 0x1f14, 0x1f97, 0x201c, 0x20a2,
+	0x2128, 0x21b0, 0x2238, 0x22c2, 0x234c, 0x23d7, 0x2463, 0x24f0,
+	0x257d, 0x260c, 0x269b, 0x272c, 0x27bd, 0x284f, 0x28e2, 0x2976,
+	0x2a0a, 0x2aa0, 0x2b36, 0x2bcd, 0x2c65, 0x2cfd, 0x2d97, 0x2e31,
+	0x2ecc, 0x2f68, 0x3004, 0x30a2, 0x3140, 0x31df, 0x327e, 0x331f,
+	0x33c0, 0x3462, 0x3504, 0x35a8, 0x364c, 0x36f0, 0x3796, 0x383c,
+	0x38e3, 0x398a, 0x3a33, 0x3adb, 0x3b85, 0x3c2f, 0x3cda, 0x3d86,
+	0x3e32, 0x3ede, 0x3f8c, 0x403a, 0x40e8, 0x4198, 0x4248, 0x42f8,
+	0x43a9, 0x445b, 0x450d, 0x45c0, 0x4673, 0x4727, 0x47db, 0x4890,
+	0x4946, 0x49fc, 0x4ab2, 0x4b69, 0x4c21, 0x4cd9, 0x4d91, 0x4e4a,
+	0x4f04, 0x4fbe, 0x5078, 0x5133, 0x51ef, 0x52aa, 0x5367, 0x5423,
+	0x54e0, 0x559e, 0x565c, 0x571a, 0x57d9, 0x5898, 0x5958, 0x5a17,
+	0x5ad8, 0x5b98, 0x5c59, 0x5d1a, 0x5ddc, 0x5e9e, 0x5f60, 0x6023,
+	0x60e6, 0x61a9, 0x626c, 0x6330, 0x63f4, 0x64b8, 0x657d, 0x6642,
+	0x6707, 0x67cc, 0x6892, 0x6958, 0x6a1e, 0x6ae4, 0x6baa, 0x6c71,
+	0x6d38, 0x6dfe, 0x6ec6, 0x6f8d, 0x7054, 0x711c, 0x71e4, 0x72ac,
+	0x7374, 0x743c, 0x7504, 0x75cd, 0x7695, 0x775e, 0x7826, 0x78ef,
+	0x79b8, 0x7a81, 0x7b49, 0x7c12, 0x7cdb, 0x7da4, 0x7e6d, 0x7f36
+};
+
+static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)
+{
+	struct vidtv_access_unit *au = kzalloc(sizeof(*au), GFP_KERNEL);
+
+	if (head) {
+		while (head->next)
+			head = head->next;
+
+		head->next = au;
+	}
+
+	return au;
+}
+
+static void vidtv_s302m_access_unit_destroy(struct vidtv_encoder *e)
+{
+	struct vidtv_access_unit *head = e->access_units;
+	struct vidtv_access_unit *tmp = NULL;
+
+	while (head) {
+		tmp = head;
+		head = head->next;
+		kfree(tmp);
+	}
+
+	e->access_units = NULL;
+}
+
+static void vidtv_s302m_alloc_au(struct vidtv_encoder *e)
+{
+	struct vidtv_access_unit *sync_au = NULL;
+	struct vidtv_access_unit *temp = NULL;
+
+	if (e->sync && e->sync->is_video_encoder) {
+		sync_au = e->sync->access_units;
+
+		while (sync_au) {
+			temp = vidtv_s302m_access_unit_init(e->access_units);
+			if (!e->access_units)
+				e->access_units = temp;
+
+			sync_au = sync_au->next;
+		}
+
+		return;
+	}
+
+	e->access_units = vidtv_s302m_access_unit_init(NULL);
+}
+
+static void
+vidtv_s302m_compute_sample_count_v(struct vidtv_encoder *e)
+{
+	struct vidtv_access_unit *au = e->access_units;
+	struct vidtv_access_unit *sync_au = e->sync->access_units;
+	u32 vau_duration_usecs;
+	u32 sample_duration_usecs;
+	u32 s;
+
+	vau_duration_usecs    = USEC_PER_SEC / e->sync->sampling_rate_hz;
+	sample_duration_usecs = USEC_PER_SEC / e->sampling_rate_hz;
+
+	while (au && sync_au) {
+		s = DIV_ROUND_UP(vau_duration_usecs, sample_duration_usecs);
+		au->num_samples = s;
+		au = au->next;
+		sync_au = sync_au->next;
+	}
+}
+
+static void
+vidtv_s302m_compute_sample_count(struct vidtv_encoder *e,
+				 u64 elapsed_time_usecs)
+{
+	/* compute sample count for 'elapsed_time_usecs' */
+	u32 sample_duration_usecs = USEC_PER_SEC / e->sampling_rate_hz;
+	struct vidtv_access_unit *au = e->access_units;
+
+	au->num_samples = (u32)div64_u64(elapsed_time_usecs, sample_duration_usecs);
+}
+
+static void vidtv_s302m_compute_pts(struct vidtv_encoder *e)
+{
+	u64 count = e->sample_count;
+	struct vidtv_access_unit *au = e->access_units;
+
+	while (au) {
+		count += au->num_samples;
+
+		au->pts = count *
+			  CLOCK_UNIT_90KHZ / e->sampling_rate_hz;
+
+		au = au->next;
+	}
+}
+
+static void vidtv_s302m_compute_pts_v(struct vidtv_encoder *e)
+{
+	struct vidtv_access_unit *au = e->access_units;
+	struct vidtv_access_unit *sync_au = e->sync->access_units;
+
+	/* use the same pts from the video access unit*/
+	while (au && sync_au) {
+		au->pts = sync_au->pts;
+		au = au->next;
+		sync_au = sync_au->next;
+	}
+}
+
+static u16 vidtv_s302m_get_sample(struct vidtv_encoder *e)
+{
+	u16 sample;
+
+	/* bug somewhere */
+	if (e->src_buf_offset > e->src_buf_sz) {
+		pr_err_ratelimited("overflow detected: %d > %d, wrapping.\n",
+				   e->src_buf_offset,
+				   e->src_buf_sz);
+
+		e->src_buf_offset = 0;
+	}
+
+	if (e->src_buf_offset >= e->src_buf_sz) {
+		/* let the source know we are out of data */
+		if (e->last_sample_cb)
+			e->last_sample_cb(e->sample_count);
+
+		e->src_buf_offset = 0;
+	}
+
+	sample = *(u16 *)(e->src_buf + e->src_buf_offset);
+
+	return sample;
+}
+
+static u32 vidtv_s302m_write_frame(struct vidtv_encoder *e,
+				   u16 sample)
+{
+	u32 nbytes = 0;
+	struct vidtv_s302m_frame_16 f = {};
+	struct vidtv_s302m_ctx *ctx = e->ctx;
+
+	/* from ffmpeg: see s302enc.c */
+
+	u8 vucf = ctx->frame_index == 0 ? 0x10 : 0;
+
+	f.data[0] = sample & 0xFF;
+	f.data[1] = (sample & 0xFF00) >>  8;
+	f.data[2] = ((sample & 0x0F)  <<  4) | vucf;
+	f.data[3] = (sample & 0x0FF0) >>  4;
+	f.data[4] = (sample & 0xF000) >> 12;
+
+	#ifdef __LITTLE_ENDIAN
+	f.data[0] = reverse[f.data[0]];
+	f.data[1] = reverse[f.data[1]];
+	f.data[2] = reverse[f.data[2]];
+	f.data[3] = reverse[f.data[3]];
+	f.data[4] = reverse[f.data[4]];
+	#endif
+
+	nbytes += vidtv_memcpy(e->encoder_buf,
+			       e->encoder_buf_offset,
+			       VIDTV_S302M_BUF_SZ,
+			       &f,
+			       sizeof(f));
+
+	e->encoder_buf_offset += nbytes;
+
+	ctx->frame_index++;
+	if (ctx->frame_index >= S302M_BLOCK_SZ)
+		ctx->frame_index = 0;
+
+	return nbytes;
+}
+
+static u32 vidtv_s302m_write_h(struct vidtv_encoder *e, u32 p_sz)
+{
+	struct vidtv_smpte_s302m_es h = {};
+	u32 nbytes = 0;
+
+	/* 2 channels, ident: 0, 16 bits per sample */
+	h.bitfield = cpu_to_be32((p_sz << 16));
+
+	nbytes += vidtv_memcpy(e->encoder_buf,
+			       e->encoder_buf_offset,
+			       e->encoder_buf_sz,
+			       &h,
+			       sizeof(h));
+
+	e->encoder_buf_offset += nbytes;
+	return nbytes;
+}
+
+static void vidtv_s302m_write_frames(struct vidtv_encoder *e)
+{
+	u32 nbytes = 0;
+	u32 nbytes_per_unit = 0;
+	u32 au_sz = 0;
+
+	struct vidtv_access_unit *au = e->access_units;
+
+	u16 sample = 0;
+
+	u32 j;
+
+	while (au) {
+		au_sz = au->num_samples *
+			sizeof(struct vidtv_s302m_frame_16);
+
+		nbytes_per_unit = vidtv_s302m_write_h(e, au_sz);
+
+		for (j = 0; j < au->num_samples; ++j) {
+			sample = vidtv_s302m_get_sample(e);
+			nbytes_per_unit += vidtv_s302m_write_frame(e, sample);
+
+			e->sample_count++;
+			e->src_buf_offset += sizeof(u16);
+		}
+
+		au->nbytes = nbytes_per_unit;
+
+		if (au_sz + sizeof(struct vidtv_smpte_s302m_es) != nbytes_per_unit) {
+			pr_warn_ratelimited("write size was %d, expected %lu\n",
+					    nbytes_per_unit,
+					    au_sz + sizeof(struct vidtv_smpte_s302m_es));
+		}
+
+		nbytes += nbytes_per_unit;
+		au->offset = nbytes - nbytes_per_unit;
+
+		nbytes_per_unit = 0;
+
+		au = au->next;
+	}
+}
+
+static void *vidtv_s302m_encode(struct vidtv_encoder *e, u64 elapsed_time)
+{
+	/*
+	 * According to SMPTE 302M, an audio access unit is specified as those
+	 * AES3 words that are associated with a corresponding video frame.
+	 * Therefore, there is one audio access unit for every video access unit
+	 * in the corresponding video encoder ('sync'), using the same values
+	 * for PTS as used by the video encoder.
+	 *
+	 * Assuming that it is also possible to send audio without any
+	 * associated video, as in a radio-like service, a single audio access unit
+	 * is created with enough audio data for 'elapsed_time'
+	 * The value of PTS is computed manually.
+	 */
+
+	if (!elapsed_time)
+		goto out;
+
+	vidtv_s302m_access_unit_destroy(e);
+	vidtv_s302m_alloc_au(e);
+
+	if (e->sync && e->sync->is_video_encoder) {
+		vidtv_s302m_compute_sample_count_v(e);
+		vidtv_s302m_compute_pts_v(e);
+	} else {
+		vidtv_s302m_compute_sample_count(e, elapsed_time);
+		vidtv_s302m_compute_pts(e);
+	}
+
+	vidtv_s302m_write_frames(e);
+
+out:
+	return e->encoder_buf;
+}
+
+static u32 vidtv_s302m_clear(struct vidtv_encoder *e)
+{
+	struct vidtv_access_unit *au = e->access_units;
+	u32 count = 0;
+
+	while (au) {
+		count++;
+		au = au->next;
+	}
+
+	vidtv_s302m_access_unit_destroy(e);
+	memset(e->encoder_buf, 0, VIDTV_S302M_BUF_SZ);
+	e->encoder_buf_offset = 0;
+
+	return count;
+}
+
+struct vidtv_encoder
+*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)
+{
+	struct vidtv_encoder *e = kzalloc(sizeof(*e), GFP_KERNEL);
+	u32 priv_sz = sizeof(struct vidtv_s302m_ctx);
+
+	e->id = S302M;
+
+	if (args.name)
+		e->name = kstrdup(args.name, GFP_KERNEL);
+
+	e->encoder_buf = vzalloc(VIDTV_S302M_BUF_SZ);
+	e->encoder_buf_sz = VIDTV_S302M_BUF_SZ;
+	e->encoder_buf_offset = 0;
+
+	e->sample_count = 0;
+
+	e->src_buf = (args.src_buf) ? args.src_buf : &s302m_sin_lut;
+	e->src_buf_sz = (args.src_buf) ? args.src_buf_sz : S302M_SIN_LUT_NUM_ELEM * sizeof(u16);
+	e->src_buf_offset = 0;
+
+	e->is_video_encoder = false;
+	e->ctx = kzalloc(priv_sz, GFP_KERNEL);
+
+	e->encode = vidtv_s302m_encode;
+	e->clear = vidtv_s302m_clear;
+
+	e->es_pid = cpu_to_be16(args.es_pid);
+	e->stream_id = cpu_to_be16(PES_PRIVATE_STREAM_1);
+
+	e->sync = args.sync;
+	e->sampling_rate_hz = S302M_SAMPLING_RATE_HZ;
+
+	e->last_sample_cb = args.last_sample_cb;
+
+	e->destroy = vidtv_s302m_encoder_destroy;
+
+	if (args.head) {
+		while (args.head->next)
+			args.head = args.head->next;
+
+		args.head->next = e;
+	}
+
+	e->next = NULL;
+
+	return e;
+}
+
+void vidtv_s302m_encoder_destroy(struct vidtv_encoder *e)
+{
+	if (e->id != S302M) {
+		pr_err_ratelimited("Encoder type mismatch, skipping.\n");
+		return;
+	}
+
+	vidtv_s302m_access_unit_destroy(e);
+	kfree(e->name);
+	vfree(e->encoder_buf);
+	kfree(e->ctx);
+	kfree(e);
+}