linux/drivers/media/test-drivers/vidtv/vidtv_s302m.c

// 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) …

#include <linux/bug.h>
#include <linux/crc32.h>
#include <linux/fixp-arith.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/printk.h>
#include <linux/ratelimit.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/vmalloc.h>

#include "vidtv_common.h"
#include "vidtv_encoder.h"
#include "vidtv_s302m.h"

#define S302M_SAMPLING_RATE_HZ …
#define PES_PRIVATE_STREAM_1 …
#define S302M_BLOCK_SZ …
#define S302M_SIN_LUT_NUM_ELEM …

/* these are retrieved empirically from ffmpeg/libavcodec */
#define FF_S302M_DEFAULT_NUM_FRAMES …
#define FF_S302M_DEFAULT_PTS_INCREMENT …
#define FF_S302M_DEFAULT_PTS_OFFSET …

/* Used by the tone generator: number of samples for PI */
#define PI …

static const u8 reverse[256] = …;

struct tone_duration { … };

#define COMPASS …
static const struct tone_duration beethoven_fur_elise[] = …;

static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)
{ … }

static void vidtv_s302m_access_unit_destroy(struct vidtv_encoder *e)
{ … }

static void vidtv_s302m_alloc_au(struct vidtv_encoder *e)
{ … }

static void
vidtv_s302m_compute_sample_count_from_video(struct vidtv_encoder *e)
{ … }

static void vidtv_s302m_compute_pts_from_video(struct vidtv_encoder *e)
{ … }

static u16 vidtv_s302m_get_sample(struct vidtv_encoder *e)
{ … }

static u32 vidtv_s302m_write_frame(struct vidtv_encoder *e,
				   u16 sample)
{ … }

static u32 vidtv_s302m_write_h(struct vidtv_encoder *e, u32 p_sz)
{ … }

static void vidtv_s302m_write_frames(struct vidtv_encoder *e)
{ … }

static void *vidtv_s302m_encode(struct vidtv_encoder *e)
{ … }

static u32 vidtv_s302m_clear(struct vidtv_encoder *e)
{ … }

struct vidtv_encoder
*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)
{ … }

void vidtv_s302m_encoder_destroy(struct vidtv_encoder *e)
{ … }