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-rw-r--r--drivers/media/test-drivers/vidtv/vidtv_s302m.h97
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diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.h b/drivers/media/test-drivers/vidtv/vidtv_s302m.h
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index 000000000..9cc94e4a8
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+++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.h
@@ -0,0 +1,97 @@
+/* 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
+ */
+
+#ifndef VIDTV_S302M_H
+#define VIDTV_S302M_H
+
+#include <linux/types.h>
+
+#include "vidtv_encoder.h"
+
+/* see SMPTE 302M 2007 clause 7.3 */
+#define VIDTV_S302M_BUF_SZ 65024
+
+/* see ETSI TS 102 154 v.1.2.1 clause 7.3.5 */
+#define VIDTV_S302M_FORMAT_IDENTIFIER 0x42535344
+
+/**
+ * struct vidtv_s302m_ctx - s302m encoder context.
+ * @enc: A pointer to the containing encoder structure.
+ * @frame_index: The current frame in a block
+ * @au_count: The total number of access units encoded up to now
+ * @last_duration: Duration of the tone currently being played
+ * @note_offset: Position at the music tone array
+ * @last_tone: Tone currently being played
+ */
+struct vidtv_s302m_ctx {
+ struct vidtv_encoder *enc;
+ u32 frame_index;
+ u32 au_count;
+ int last_duration;
+ unsigned int note_offset;
+ enum musical_notes last_tone;
+};
+
+/*
+ * struct vidtv_smpte_s302m_es - s302m MPEG Elementary Stream header.
+ *
+ * See SMPTE 302M 2007 table 1.
+ */
+struct vidtv_smpte_s302m_es {
+ /*
+ *
+ * audio_packet_size:16;
+ * num_channels:2;
+ * channel_identification:8;
+ * bits_per_sample:2; // 0x0 for 16bits
+ * zero:4;
+ */
+ __be32 bitfield;
+} __packed;
+
+struct vidtv_s302m_frame_16 {
+ u8 data[5];
+} __packed;
+
+/**
+ * struct vidtv_s302m_encoder_init_args - Args for the s302m encoder.
+ *
+ * @name: A name to identify this particular instance
+ * @src_buf: The source buffer, encoder will default to a sine wave if this is NULL.
+ * @src_buf_sz: The size of the source buffer.
+ * @es_pid: The MPEG Elementary Stream PID to use.
+ * @sync: Attempt to synchronize audio with this video encoder, if not NULL.
+ * @last_sample_cb: A callback called when the encoder runs out of data.
+ * @head: Add to this chain
+ */
+struct vidtv_s302m_encoder_init_args {
+ char *name;
+ void *src_buf;
+ u32 src_buf_sz;
+ u16 es_pid;
+ struct vidtv_encoder *sync;
+ void (*last_sample_cb)(u32 sample_no);
+
+ struct vidtv_encoder *head;
+};
+
+struct vidtv_encoder
+*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args);
+
+void vidtv_s302m_encoder_destroy(struct vidtv_encoder *encoder);
+
+#endif /* VIDTV_S302M_H */