[RFC, WIP, v4 08/11] media: vidtv: implement a PSI generator

["Daniel W. S. Almeida" <dwlsalmeida@gmail.com>]

From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>

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 this commit adds support for working with 3 PSI tables:
PAT, PMT and SDT.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
---
 drivers/media/test-drivers/vidtv/Makefile    |    2 +-
 drivers/media/test-drivers/vidtv/vidtv_psi.c | 1137 ++++++++++++++++++
 drivers/media/test-drivers/vidtv/vidtv_psi.h |  357 ++++++
 3 files changed, 1495 insertions(+), 1 deletion(-)
 create mode 100644 drivers/media/test-drivers/vidtv/vidtv_psi.c
 create mode 100644 drivers/media/test-drivers/vidtv/vidtv_psi.h

diff --git a/drivers/media/test-drivers/vidtv/Makefile b/drivers/media/test-drivers/vidtv/Makefile
index 92001bc348615..e4f744aa53136 100644
--- a/drivers/media/test-drivers/vidtv/Makefile
+++ b/drivers/media/test-drivers/vidtv/Makefile
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
 vidtv_demod-objs := vidtv_common.o
-vidtv_bridge-objs := vidtv_common.o vidtv_ts.o
+vidtv_bridge-objs := vidtv_common.o vidtv_ts.o vidtv_psi.o
 
 obj-$(CONFIG_DVB_VIDTV)	+= vidtv_tuner.o vidtv_demod.o vidtv_bridge.o
diff --git a/drivers/media/test-drivers/vidtv/vidtv_psi.c b/drivers/media/test-drivers/vidtv/vidtv_psi.c
new file mode 100644
index 0000000000000..191d37a248923
--- /dev/null
+++ b/drivers/media/test-drivers/vidtv/vidtv_psi.c
@@ -0,0 +1,1137 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file contains the logic to work with MPEG Program-Specific Information.
+ * These are defined both in ISO/IEC 13818-1 (systems) and ETSI EN 300 468.
+ * PSI is carried in the form of table structures, and although each table might
+ * technically be broken into one or more sections, we do not do this here,
+ * hence 'table' and 'section' are interchangeable for us.
+ *
+ * This code currently supports three tables: PAT, PMT and SDT. These are the
+ * bare minimum to get userspace to recognize our MPEG transport stream. It can
+ * be extended to support more PSI tables in the future.
+ *
+ * A note on endianness: MPEG layout is big-endian, therefore:
+ * - All fields spanning more than a byte must undergo 'cpu_to_beXX()' before
+ * serialization. These convertions are done in the *_write_into() functions.
+ *
+ * - All byte sized bitfields must have their ordering reversed if
+ *  __LITTLE_ENDIAN_BITFIELD is defined.
+ *
+ * Written by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/string.h>
+#include <linux/printk.h>
+
+#include "vidtv_psi.h"
+#include "vidtv_common.h"
+#include "vidtv_ts.h"
+
+#define CRC_SIZE_IN_BYTES 4
+
+static u32 vidtv_psi_ts_psi_write_stuffing(void *to,
+					   u32 len,
+					   u32 offset,
+					   u32 buf_sz)
+{
+	return vidtv_memset(to, 0xff, len, offset, buf_sz);
+}
+
+static u32
+vidtv_psi_ts_psi_write_into(struct psi_write_args args)
+{
+	/*
+	 * Packetize PSI sections into TS packets:
+	 * push a TS header (4bytes) every 184 bytes
+	 * manage the continuity_counter
+	 * add stuffing after the CRC
+	 */
+
+	u32  nbytes_past_boundary = (args.dest_offset % TS_PACKET_LEN);
+	bool aligned              = nbytes_past_boundary == 0;
+
+	/*
+	 * whether we need to fragment the data into multiple ts packets
+	 * if we are aligned we need to spare one byte for the pointer_field
+	 */
+	bool split = (aligned) ?
+		     args.len > TS_PAYLOAD_LEN - 1 :
+		     nbytes_past_boundary + args.len > TS_PACKET_LEN;
+
+	/* how much we can write in this packet */
+	u32 payload_write_len = (split) ?
+				(aligned)     ? TS_PAYLOAD_LEN       :
+				TS_PACKET_LEN - nbytes_past_boundary :
+				args.len;
+
+	struct psi_write_args new_args = {0};
+	struct vidtv_mpeg_ts ts_header = {0};
+
+	u32 nbytes = 0;  /* number of bytes written by this function */
+	u32 temp   = 0;
+
+	/* Just a sanity check, should not really happen because we stuff
+	 * the packet when we finish a section, i.e. when we write the crc at
+	 * the end. But if this happens then we have messed up the logic
+	 * somewhere.
+	 */
+	WARN_ON(args.new_psi_section && !aligned);
+
+	if (aligned) {
+		/* if at a packet boundary, write a new TS header */
+		ts_header.sync_byte          = TS_SYNC_BYTE;
+		ts_header.tei                = 0;
+		ts_header.payload_start      = 1;
+		ts_header.pid                = args.pid;
+		ts_header.priority           = 0;
+		ts_header.scrambling         = 0;
+		ts_header.continuity_counter = *args.continuity_counter;
+		ts_header.payload            = 1;
+		/* no adaptation field */
+		ts_header.adaptation_field = 0;
+
+		cpu_to_be16s(&ts_header.bitfield);
+
+		/* copy the header */
+		nbytes += vidtv_memcpy(args.dest_buf +
+				       args.dest_offset +
+				       nbytes,
+				       &ts_header,
+				       sizeof(ts_header),
+				       args.dest_offset + nbytes,
+				       args.dest_buf_sz);
+
+		be16_to_cpus(&ts_header.bitfield);
+
+		/*
+		 * increment the countinuity counter since we have started
+		 * a new packet
+		 */
+		vidtv_ts_inc_cc(args.continuity_counter);
+	}
+
+	if (args.new_psi_section) {
+		/* write the pointer_field in the first byte of the payload */
+		temp = vidtv_memset(args.dest_buf + args.dest_offset + nbytes,
+				    0x0,
+				    1,
+				    args.dest_offset + nbytes,
+				    args.dest_buf_sz);
+		/* one byte was used by the pointer field*/
+		nbytes += temp;
+		if (payload_write_len == TS_PAYLOAD_LEN)
+			payload_write_len -= temp;
+	}
+
+	/* write as much of the payload as we possibly can */
+	nbytes += vidtv_memcpy(args.dest_buf + args.dest_offset + nbytes,
+			       args.from,
+			       payload_write_len,
+			       args.dest_offset + nbytes,
+			       args.dest_buf_sz);
+
+	if (split) {
+		/* 'payload_write_len' written from a total of 'len' requested*/
+		args.len -= payload_write_len;
+		/*
+		 * recursively write the rest of the data until we do not
+		 * need to split it anymore
+		 */
+		memcpy(&new_args, &args, sizeof(struct psi_write_args));
+		new_args.from            = args.from + payload_write_len;
+		new_args.dest_offset     = args.dest_offset + nbytes;
+		new_args.new_psi_section = false;
+
+		nbytes += vidtv_psi_ts_psi_write_into(new_args);
+	}
+
+	/*
+	 * as the CRC is last in the section, stuff the rest of the
+	 * packet if there is any remaining space in there
+	 */
+	if (args.is_crc)
+		nbytes += vidtv_psi_ts_psi_write_stuffing(args.dest_buf +
+							  args.dest_offset +
+							  nbytes,
+							  TS_PACKET_LEN -
+							  payload_write_len,
+							  args.dest_offset +
+							  nbytes,
+							  args.dest_buf_sz);
+
+	return nbytes;
+}
+
+static u32 table_section_crc32_write_into(struct crc32_write_args args)
+{
+	/* the CRC is the last entry in the section */
+	u32 nbytes = 0;
+	u32 crc;
+	struct psi_write_args psi_args = {0};
+
+	crc = crc32_be(0, args.dest_buf, args.dest_offset);
+
+	psi_args.dest_buf           = args.dest_buf;
+	psi_args.from               = &crc;
+	psi_args.len                = CRC_SIZE_IN_BYTES;
+	psi_args.dest_offset        = args.dest_offset;
+	psi_args.pid                = args.pid;
+	psi_args.new_psi_section    = false;
+	psi_args.continuity_counter = args.continuity_counter;
+	psi_args.is_crc             = true;
+	psi_args.dest_buf_sz        = args.dest_buf_sz;
+
+	cpu_to_be32s(&crc);
+	nbytes += vidtv_psi_ts_psi_write_into(psi_args);
+	be32_to_cpus(&crc);
+
+	return nbytes;
+}
+
+struct vidtv_psi_desc *vidtv_psi_desc_init(struct vidtv_psi_desc *head,
+					   u8 type,
+					   u8 length)
+{
+	struct vidtv_psi_desc *desc;
+
+	/* alloc enough memory for the flexible array too */
+	desc = kzalloc(sizeof(*desc) + length, GFP_KERNEL);
+
+	desc->type   = type;
+	desc->length = length;
+
+	if (head) {
+		while (head->next)
+			head = head->next;
+
+		head->next = desc;
+	}
+
+	return desc;
+}
+
+void vidtv_psi_desc_destroy(struct vidtv_psi_desc *desc)
+{
+	struct vidtv_psi_desc *curr = desc;
+	struct vidtv_psi_desc *tmp  = NULL;
+
+	while (curr) {
+		tmp  = curr;
+		curr = curr->next;
+		kfree(tmp);
+	}
+}
+
+static u32
+vidtv_psi_desc_comp_len(struct vidtv_psi_desc *desc)
+{
+	u32 length = 0;
+
+	if (!desc)
+		return 0;
+
+	while (desc) {
+		length += desc->length;
+		desc    = desc->next;
+	}
+
+	return length;
+}
+
+void vidtv_psi_desc_assign(struct vidtv_psi_desc **to,
+			   struct vidtv_psi_desc *desc)
+{
+	/*
+	 * Caller must recompute the section length afterwards at some point
+	 * This function transfers ownedship of desc.
+	 * Start by cleaning the old data
+	 */
+	if (*to)
+		vidtv_psi_desc_destroy(*to);
+
+	*to = desc;  /* reassign pointer */
+}
+
+static void vidtv_psi_desc_to_be(struct vidtv_psi_desc *desc)
+{
+	/*
+	 * Convert descriptor endianness to big-endian on a field-by-field basis
+	 * where applicable
+	 */
+
+	switch (desc->type) {
+	/* nothing do do */
+	case SERVICE_DESCRIPTOR:
+		break;
+	case REGISTRATION_DESCRIPTOR:
+		cpu_to_be32s(&((struct vidtv_psi_desc_registration *)
+			     desc)->format_identifier);
+		pr_alert("%s: descriptor type %d found\n",
+			 __func__,
+			 desc->type);
+		pr_alert("%s: change 'additional_info' endianness before calling\n",
+			 __func__);
+		break;
+	default:
+		pr_err("%s: descriptor type %d not implemented, skipping\n",
+		       __func__,
+		       desc->type);
+		break;
+	}
+}
+
+static void vidtv_psi_desc_to_cpu(struct vidtv_psi_desc *desc)
+{
+	/*
+	 * Convert descriptor endianness to native on a field-by-field basis
+	 * where applicable
+	 */
+
+	switch (desc->type) {
+	/* nothing do do */
+	case SERVICE_DESCRIPTOR:
+		break;
+	case REGISTRATION_DESCRIPTOR:
+		be32_to_cpus(&((struct vidtv_psi_desc_registration *)
+			     desc)->format_identifier);
+		pr_alert("%s: descriptor type %d found\n",
+			 __func__,
+			 desc->type);
+		pr_alert("%s: change 'additional_info' endianness before calling\n",
+			 __func__);
+		break;
+	default:
+		pr_err("%s: descriptor type %d not implemented, skipping\n",
+		       __func__,
+		       desc->type);
+		break;
+	}
+}
+
+static u32 vidtv_psi_desc_write_into(struct desc_write_args args)
+{
+	/* the number of bytes written by this function */
+	u32    nbytes                  = 0;
+	struct psi_write_args psi_args = {0};
+
+	psi_args.dest_buf = args.dest_buf;
+	psi_args.from     = args.desc;
+
+	psi_args.len      = sizeof_field(struct vidtv_psi_desc, type) +
+			    sizeof_field(struct vidtv_psi_desc, length);
+
+	psi_args.dest_offset        = args.dest_offset;
+	psi_args.pid                = args.pid;
+	psi_args.new_psi_section    = false;
+	psi_args.continuity_counter = args.continuity_counter;
+	psi_args.is_crc             = false;
+	psi_args.dest_buf_sz        = args.dest_buf_sz;
+
+	vidtv_psi_desc_to_be(args.desc);
+
+	nbytes += vidtv_psi_ts_psi_write_into(psi_args);
+
+	/* move 'from' pointer to point to u8 data[] */
+	psi_args.from = args.desc +
+			sizeof_field(struct vidtv_psi_desc, type) +
+			sizeof_field(struct vidtv_psi_desc, length) +
+			sizeof(struct vidtv_psi_desc *);
+
+	psi_args.len         = args.desc->length;
+	psi_args.dest_offset = args.dest_offset + nbytes;
+
+	nbytes += vidtv_psi_ts_psi_write_into(psi_args);
+
+	vidtv_psi_desc_to_cpu(args.desc);
+
+	return nbytes;
+}
+
+static u32
+vidtv_psi_table_header_write_into(struct header_write_args args)
+{
+	/* the number of bytes written by this function */
+	u32    nbytes                  = 0;
+	struct psi_write_args psi_args = {0};
+
+	psi_args.dest_buf           = args.dest_buf;
+	psi_args.from               = args.h;
+	psi_args.len                = sizeof(struct vidtv_psi_table_header);
+	psi_args.dest_offset        = args.dest_offset;
+	psi_args.pid                = args.pid;
+	psi_args.new_psi_section    = true;
+	psi_args.continuity_counter = args.continuity_counter;
+	psi_args.is_crc             = false;
+	psi_args.dest_buf_sz        = args.dest_buf_sz;
+
+	cpu_to_be16s(&args.h->bitfield);
+	cpu_to_be16s(&args.h->id);
+
+	nbytes += vidtv_psi_ts_psi_write_into(psi_args);
+
+	be16_to_cpus(&args.h->bitfield);
+	be16_to_cpus(&args.h->id);
+
+	return nbytes;
+}
+
+void
+vidtv_psi_pat_table_comp_sec_len(struct vidtv_psi_table_pat *pat)
+{
+	/* see ISO/IEC 13818-1 : 2000 p.43 */
+	u16 length = 0;
+	u32 i;
+
+	/* from immediately after 'section_length' until 'last_section_number'*/
+	length += PAT_LEN_UNTIL_LAST_SECTION_NUMBER;
+
+	/* do not count the pointer */
+	for (i = 0; i < pat->programs; ++i)
+		length += sizeof(struct vidtv_psi_table_pat_program) -
+			  sizeof(struct vidtv_psi_table_pat_program *);
+
+	length += CRC_SIZE_IN_BYTES;
+
+	WARN_ON(length > MAX_SECTION_LEN);
+	pat->header.section_length = length;
+}
+
+void vidtv_psi_pmt_table_comp_sec_len(struct vidtv_psi_table_pmt *pmt)
+{
+	/* see ISO/IEC 13818-1 : 2000 p.46 */
+	u16    length                        = 0;
+	struct vidtv_psi_table_pmt_stream *s = pmt->stream;
+
+	/* from immediately after 'section_length' until 'program_info_length'*/
+	length += PMT_LEN_UNTIL_PROGRAM_INFO_LENGTH;
+
+	pmt->desc_length  = vidtv_psi_desc_comp_len(pmt->descriptor);
+	length           += pmt->desc_length;
+
+	while (s) {
+		/* skip both pointers at the end */
+		length += sizeof(struct vidtv_psi_table_pmt_stream) -
+			  sizeof(struct vidtv_psi_desc *) -
+			  sizeof(struct vidtv_psi_table_pmt_stream *);
+
+		s->desc_length  = vidtv_psi_desc_comp_len(s->descriptor);
+		length         += s->desc_length;
+
+		s = s->next;
+	}
+
+	length += CRC_SIZE_IN_BYTES;
+
+	WARN_ON(length > MAX_SECTION_LEN);
+	pmt->header.section_length = length;
+}
+
+void vidtv_psi_sdt_table_comp_sec_len(struct vidtv_psi_table_sdt *sdt)
+{
+	/* see ETSI EN 300 468 V 1.10.1 p.24 */
+	u16    length                         = 0;
+	struct vidtv_psi_table_sdt_service *s = sdt->service;
+
+	/*
+	 * from immediately after 'section_length' until
+	 * 'reserved_for_future_use'
+	 */
+	length += SDT_LEN_UNTIL_RESERVED_FOR_FUTURE_USE;
+
+	while (s) {
+		/* skip both pointers at the end */
+		length += sizeof(struct vidtv_psi_table_sdt_service) -
+			  sizeof(struct vidtv_psi_desc *) -
+			  sizeof(struct vidtv_psi_table_sdt_service *);
+
+		s->desc_length  = vidtv_psi_desc_comp_len(s->descriptor);
+		length         += s->desc_length;
+
+		s = s->next;
+	}
+
+	length += CRC_SIZE_IN_BYTES;
+
+	WARN_ON(length > MAX_SECTION_LEN);
+	sdt->header.section_length = length;
+}
+
+struct vidtv_psi_table_pat_program*
+vidtv_psi_pat_program_init(struct vidtv_psi_table_pat_program *head,
+			   u16 service_id,
+			   u16 pid)
+{
+	/*
+	 * if 'head' is attached to a table, caller should recompute
+	 * the section length afterwards at some point
+	 */
+	struct vidtv_psi_table_pat_program *program;
+
+	program = kzalloc(sizeof(*program), GFP_KERNEL);
+
+	program->service_id = service_id;
+	/* pid for the PMT section in the TS */
+	program->pid        = pid;
+	program->next       = NULL;
+	program->reserved   = 0x7;
+
+	if (head) {
+		while (head->next)
+			head = head->next;
+
+		head->next = program;
+	}
+
+	return program;
+}
+
+void
+vidtv_psi_pat_program_destroy(struct vidtv_psi_table_pat_program *p)
+{
+	struct vidtv_psi_table_pat_program *curr = p;
+	struct vidtv_psi_table_pat_program *tmp  = NULL;
+
+	while (curr) {
+		tmp  = curr;
+		curr = curr->next;
+		kfree(tmp);
+	}
+}
+
+void
+vidtv_psi_pat_program_assign(struct vidtv_psi_table_pat *pat,
+			     struct vidtv_psi_table_pat_program *p)
+{
+	/* This function transfers ownership of p to the table */
+
+	u16    program_count                        = 0;
+	struct vidtv_psi_table_pat_program *program = p;
+	struct vidtv_psi_table_pat_program *temp    = pat->program;
+
+	while (program) {
+		++program_count;
+		program = program->next;
+	}
+
+	pat->programs = program_count;
+	pat->program  = p;
+
+	/* Recompute section length */
+	vidtv_psi_pat_table_comp_sec_len(pat);
+
+	/* reassign if the new size is too big */
+	if (pat->header.section_length > MAX_SECTION_LEN)
+		vidtv_psi_pat_program_assign(pat, temp);
+	else
+		vidtv_psi_pat_program_destroy(temp);
+}
+
+void vidtv_psi_pat_table_init(struct vidtv_psi_table_pat *pat,
+			      bool update_version_num,
+			      u16 transport_stream_id)
+{
+	static u8 pat_version;
+
+	pat->header.table_id = 0x0;
+	pat->header.syntax   = 0x1;
+	pat->header.zero     = 0x0;
+	pat->header.one      = 0x03;
+
+	/* transport stream ID, at will */
+	pat->header.id           = transport_stream_id;
+	pat->header.current_next = 0x1;
+
+	/* ETSI 300 468: indicates changes in the TS described by this table*/
+	if (update_version_num)
+		++pat_version;
+
+	pat->header.version = pat_version;
+
+	pat->header.one2         = 0x03;
+	pat->header.section_id   = 0x0;
+	pat->header.last_section = 0x0;
+
+	pat->programs = 0;
+
+	vidtv_psi_pat_table_comp_sec_len(pat);
+}
+
+u32 vidtv_psi_pat_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_pat *pat,
+			     u32 buf_sz,
+			     u8 *continuity_counter)
+{
+	/* the number of bytes written by this function */
+	u32   nbytes      = 0;
+	const u16 pat_pid = VIDTV_PAT_PID;
+
+	struct vidtv_psi_table_pat_program *p = pat->program;
+	struct header_write_args h_args       = {0};
+	struct psi_write_args args            = {0};
+	struct crc32_write_args c_args        = {0};
+
+	vidtv_psi_pat_table_comp_sec_len(pat);
+
+	h_args.dest_buf           = buf;
+	h_args.dest_offset        = offset;
+	h_args.h                  = &pat->header;
+	h_args.pid                = pat_pid;
+	h_args.continuity_counter = continuity_counter;
+	h_args.dest_buf_sz        = buf_sz;
+
+	nbytes += vidtv_psi_table_header_write_into(h_args);
+
+	/* note that the field 'u16 programs' is not really part of the PAT */
+
+	args.dest_buf           = buf;
+	args.pid                = pat_pid;
+	args.new_psi_section    = false;
+	args.continuity_counter = continuity_counter;
+	args.is_crc             = false;
+	args.dest_buf_sz        = buf_sz;
+
+	while (p) {
+		/* copy the PAT programs */
+		cpu_to_be16s(&p->service_id);
+		cpu_to_be16s(&p->bitfield);
+
+		args.from = p;
+		/* skip the pointer */
+		args.len = sizeof(*p) -
+			   sizeof(struct vidtv_psi_table_pat_program *);
+		args.dest_offset = offset + nbytes;
+
+		nbytes += vidtv_psi_ts_psi_write_into(args);
+
+		be16_to_cpus(&p->service_id);
+		be16_to_cpus(&p->bitfield);
+
+		p = p->next;
+	}
+
+	c_args.dest_buf           = buf;
+	c_args.dest_offset        = offset + nbytes;
+	c_args.pid                = pat_pid;
+	c_args.continuity_counter = continuity_counter;
+	c_args.dest_buf_sz        = buf_sz;
+
+	nbytes += table_section_crc32_write_into(c_args);
+
+	return nbytes;
+}
+
+void
+vidtv_psi_pat_table_destroy(struct vidtv_psi_table_pat *p)
+{
+	vidtv_psi_pat_program_destroy(p->program);
+}
+
+struct vidtv_psi_table_pmt_stream*
+vidtv_psi_pmt_stream_init(struct vidtv_psi_table_pmt_stream *head,
+			  enum vidtv_psi_stream_types stream_type,
+			  u16 es_pid)
+{
+	struct vidtv_psi_table_pmt_stream *stream;
+
+	stream = kzalloc(sizeof(*stream), GFP_KERNEL);
+
+	stream->type           = stream_type;
+	stream->elementary_pid = es_pid;
+	stream->reserved       = 0x07;
+
+	stream->desc_length = vidtv_psi_desc_comp_len(stream->descriptor);
+
+	stream->zero      = 0x0;
+	stream->reserved2 = 0x0f;
+
+	if (head) {
+		while (head->next)
+			head = head->next;
+
+		head->next = stream;
+	}
+
+	return stream;
+}
+
+void vidtv_psi_pmt_stream_destroy(struct vidtv_psi_table_pmt_stream *s)
+{
+	struct vidtv_psi_table_pmt_stream *curr_stream = s;
+	struct vidtv_psi_table_pmt_stream *tmp_stream  = NULL;
+
+	while (curr_stream) {
+		tmp_stream  = curr_stream;
+		curr_stream = curr_stream->next;
+		kfree(tmp_stream);
+	}
+}
+
+void vidtv_psi_pmt_stream_assign(struct vidtv_psi_table_pmt *pmt,
+				 struct vidtv_psi_table_pmt_stream *s)
+{
+	/* This function transfers ownership of s to the table */
+	struct vidtv_psi_table_pmt_stream *stream = s;
+	struct vidtv_psi_desc *desc               = s->descriptor;
+	struct vidtv_psi_table_pmt_stream *temp   = pmt->stream;
+
+	while (stream)
+		stream = stream->next;
+
+	while (desc)
+		desc = desc->next;
+
+	pmt->stream = s;
+	/* Recompute section length */
+	vidtv_psi_pmt_table_comp_sec_len(pmt);
+
+	/* reassign if the new size is too big */
+	if (pmt->header.section_length > MAX_SECTION_LEN)
+		vidtv_psi_pmt_stream_assign(pmt, temp);
+	else
+		vidtv_psi_pmt_stream_destroy(temp);
+}
+
+u16 vidtv_psi_pmt_get_pid(struct vidtv_psi_table_pmt *section,
+			  struct vidtv_psi_table_pat *pat)
+{
+	struct vidtv_psi_table_pat_program *program = pat->program;
+
+	/*
+	 * service_id is the same as program_number in the
+	 * corresponding program_map_section
+	 * see ETSI EN 300 468 v1.15.1 p. 24
+	 */
+	while (program) {
+		if (program->service_id == section->header.id)
+			return pat->program->pid;
+
+		program = program->next;
+	}
+
+	return TS_LAST_VALID_PID + 1; /* not found */
+}
+
+void vidtv_psi_pmt_table_init(struct vidtv_psi_table_pmt *pmt,
+			      bool update_version_num,
+			      u16 program_number,
+			      u16 pcr_pid)
+{
+	static u8 pmt_version;
+
+	pmt->header.table_id = 0x2;
+	pmt->header.syntax   = 0x1;
+	pmt->header.zero     = 0x0;
+	pmt->header.one      = 0x3;
+
+	pmt->header.id           = program_number;
+	pmt->header.current_next = 0x1;
+
+	/* ETSI 300 468: indicates changes in the TS described by this table*/
+	if (update_version_num)
+		++pmt_version;
+
+	pmt->header.version = pmt_version;
+
+	pmt->header.one2         = 0x3;
+	pmt->header.section_id   = 0;
+	pmt->header.last_section = 0;
+
+	pmt->pcr_pid   = (pcr_pid) ? pcr_pid : 0x1fff;
+	pmt->reserved2 = 0x03;
+
+	pmt->reserved3 = 0x0f;
+	pmt->zero3     = 0x0;
+
+	pmt->desc_length = vidtv_psi_desc_comp_len(pmt->descriptor);
+
+	vidtv_psi_pmt_table_comp_sec_len(pmt);
+}
+
+u32 vidtv_psi_pmt_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_pmt *pmt,
+			     u16 pid,
+			     u32 buf_sz,
+			     u8 *continuity_counter)
+{
+	/* the number of bytes written by this function */
+	u32    nbytes                             = 0;
+	struct vidtv_psi_desc *table_descriptor   = pmt->descriptor;
+	struct vidtv_psi_table_pmt_stream *stream = pmt->stream;
+	struct vidtv_psi_desc *stream_descriptor  = (stream) ?
+						    pmt->stream->descriptor :
+						    NULL;
+
+	struct header_write_args h_args = {0};
+	struct psi_write_args args      = {0};
+	struct desc_write_args d_args   = {0};
+	struct crc32_write_args c_args  = {0};
+
+	vidtv_psi_pmt_table_comp_sec_len(pmt);
+
+	h_args.dest_buf           = buf;
+	h_args.dest_offset        = offset;
+	h_args.h                  = &pmt->header;
+	h_args.pid                = pid;
+	h_args.continuity_counter = continuity_counter;
+	h_args.dest_buf_sz        = buf_sz;
+
+	nbytes += vidtv_psi_table_header_write_into(h_args);
+
+	/* write the two bitfields */
+	cpu_to_be16s(&pmt->bitfield);
+	cpu_to_be16s(&pmt->bitfield2);
+
+	args.dest_buf = buf;
+	args.from     = pmt + sizeof(struct vidtv_psi_table_header);
+	args.len      = sizeof_field(struct vidtv_psi_table_pmt, bitfield) +
+			sizeof_field(struct vidtv_psi_table_pmt, bitfield2);
+	args.dest_offset        = offset + nbytes;
+	args.pid                = pid;
+	args.new_psi_section    = false;
+	args.continuity_counter = continuity_counter;
+	args.is_crc             = false;
+	args.dest_buf_sz        = buf_sz;
+
+	nbytes += vidtv_psi_ts_psi_write_into(args);
+
+	be16_to_cpus(&pmt->bitfield);
+	be16_to_cpus(&pmt->bitfield2);
+
+	while (table_descriptor) {
+		/* write the descriptors, if any */
+		d_args.dest_buf           = buf;
+		d_args.dest_offset        = offset + nbytes;
+		d_args.desc               = table_descriptor;
+		d_args.pid                = pid;
+		d_args.continuity_counter = continuity_counter;
+		d_args.dest_buf_sz        = buf_sz;
+
+		vidtv_psi_desc_to_be(d_args.desc);
+		nbytes += vidtv_psi_desc_write_into(d_args);
+		vidtv_psi_desc_to_cpu(d_args.desc);
+
+		table_descriptor = table_descriptor->next;
+	}
+
+	while (stream) {
+		/* write the streams, if any */
+		args.from = stream;
+		args.len  = sizeof_field(struct vidtv_psi_table_pmt_stream,
+					 type) +
+			    sizeof_field(struct vidtv_psi_table_pmt_stream,
+					 bitfield) +
+			    sizeof_field(struct vidtv_psi_table_pmt_stream,
+					 bitfield2);
+		args.dest_offset = offset + nbytes;
+
+		cpu_to_be16s(&stream->bitfield);
+		cpu_to_be16s(&stream->bitfield2);
+
+		nbytes += vidtv_psi_ts_psi_write_into(args);
+
+		be16_to_cpus(&stream->bitfield);
+		be16_to_cpus(&stream->bitfield2);
+
+		while (stream_descriptor) {
+			/* write the stream descriptors, if any */
+			d_args.desc        = stream_descriptor;
+			d_args.dest_offset = offset + nbytes;
+
+			vidtv_psi_desc_to_be(d_args.desc);
+
+			nbytes += vidtv_psi_desc_write_into(d_args);
+
+			vidtv_psi_desc_to_cpu(d_args.desc);
+
+			stream_descriptor = stream_descriptor->next;
+		}
+
+		stream = stream->next;
+	}
+
+	c_args.dest_buf           = buf;
+	c_args.dest_offset        = offset + nbytes;
+	c_args.pid                = pid;
+	c_args.continuity_counter = continuity_counter;
+	c_args.dest_buf_sz        = buf_sz;
+
+	nbytes += table_section_crc32_write_into(c_args);
+
+	return nbytes;
+}
+
+void vidtv_psi_pmt_table_destroy(struct vidtv_psi_table_pmt *pmt)
+{
+	struct vidtv_psi_desc *curr_desc = pmt->descriptor;
+	struct vidtv_psi_desc *tmp_desc  = NULL;
+
+	while (curr_desc) {
+		tmp_desc  = curr_desc;
+		curr_desc = curr_desc->next;
+		vidtv_psi_desc_destroy(tmp_desc);
+		kfree(tmp_desc);
+	}
+
+	vidtv_psi_pmt_stream_destroy(pmt->stream);
+}
+
+void vidtv_psi_sdt_table_init(struct vidtv_psi_table_sdt *sdt,
+			      bool update_version_num,
+			      u16 transport_stream_id)
+{
+	static u8 sdt_version;
+
+	sdt->header.table_id = 0x42;
+
+	sdt->header.one  = 0x3;
+	sdt->header.zero = 0x1;
+	/*
+	 * The PAT, PMT, and CAT all set this to 0.
+	 * Other tables set this to 1.
+	 */
+	sdt->header.syntax = 0x1;
+
+	/*
+	 * This is a 16-bit field which serves as a label for identification
+	 * of the TS, about which the SDT informs, from any other multiplex
+	 * within the delivery system.
+	 */
+	sdt->header.id           = transport_stream_id;
+	sdt->header.current_next = 0x1;
+
+	/* ETSI 300 468: indicates changes in the TS described by this table*/
+	if (update_version_num)
+		++sdt_version;
+
+	sdt->header.version = sdt_version;
+
+	sdt->header.one2         = 0x3;
+	sdt->header.section_id   = 0;
+	sdt->header.last_section = 0;
+
+	sdt->network_id = transport_stream_id;
+	sdt->reserved   = 0xff;
+
+	vidtv_psi_sdt_table_comp_sec_len(sdt);
+}
+
+u32 vidtv_psi_sdt_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_sdt *sdt,
+			     u32 buf_sz,
+			     u8 *continuity_counter)
+{
+	u32 nbytes  = 0;              /* the number of bytes written */
+	u16 sdt_pid = VIDTV_SDT_PID;  /* see ETSI EN 300 468 v1.15.1 p. 11 */
+
+	struct vidtv_psi_table_sdt_service *service = sdt->service;
+	struct vidtv_psi_desc *service_desc = (sdt->service) ?
+					      sdt->service->descriptor :
+					      NULL;
+
+	struct header_write_args h_args = {0};
+	struct psi_write_args args      = {0};
+	struct desc_write_args d_args   = {0};
+	struct crc32_write_args c_args  = {0};
+
+	vidtv_psi_sdt_table_comp_sec_len(sdt);
+
+	h_args.dest_buf           = buf;
+	h_args.dest_offset        = offset;
+	h_args.h                  = &sdt->header;
+	h_args.pid                = sdt_pid;
+	h_args.continuity_counter = continuity_counter;
+	h_args.dest_buf_sz        = buf_sz;
+
+	nbytes += vidtv_psi_table_header_write_into(h_args);
+
+	args.dest_buf = buf;
+	args.from     = sdt + sizeof(struct vidtv_psi_table_header);
+
+	args.len      = sizeof_field(struct vidtv_psi_table_sdt, network_id) +
+			sizeof_field(struct vidtv_psi_table_sdt, reserved);
+
+	args.dest_offset        = offset + nbytes;
+	args.pid                = sdt_pid;
+	args.new_psi_section    = false;
+	args.continuity_counter = continuity_counter;
+	args.is_crc             = false;
+	args.dest_buf_sz        = buf_sz;
+
+	/* copy u16 network_id + u8 reserved)*/
+	cpu_to_be16s(&sdt->network_id);
+
+	nbytes += vidtv_psi_ts_psi_write_into(args);
+
+	be16_to_cpus(&sdt->network_id);
+
+	while (service) {
+		/* copy the services, if any */
+		args.from = service;
+		/* skip both pointers at the end */
+		args.len = sizeof(struct vidtv_psi_table_sdt_service) -
+			   sizeof(struct vidtv_psi_desc *) -
+			   sizeof(struct vidtv_psi_table_sdt_service *);
+		args.dest_offset = offset + nbytes;
+
+		cpu_to_be16s(&service->service_id);
+		cpu_to_be16s(&service->bitfield);
+
+		nbytes += vidtv_psi_ts_psi_write_into(args);
+
+		be16_to_cpus(&service->service_id);
+		be16_to_cpus(&service->bitfield);
+
+		while (service_desc) {
+			/* copy the service descriptors, if any */
+			d_args.dest_buf           = buf;
+			d_args.dest_offset        = offset + nbytes;
+			d_args.desc               = service_desc;
+			d_args.pid                = sdt_pid;
+			d_args.continuity_counter = continuity_counter;
+			d_args.dest_buf_sz        = buf_sz;
+
+			vidtv_psi_desc_to_be(d_args.desc);
+
+			nbytes += vidtv_psi_desc_write_into(d_args);
+
+			vidtv_psi_desc_to_cpu(d_args.desc);
+
+			service_desc = service_desc->next;
+		}
+
+		service = service->next;
+	}
+
+	c_args.dest_buf           = buf;
+	c_args.dest_offset        = offset + nbytes;
+	c_args.pid                = sdt_pid;
+	c_args.continuity_counter = continuity_counter;
+	c_args.dest_buf_sz        = buf_sz;
+
+	nbytes += table_section_crc32_write_into(c_args);
+
+	return nbytes;
+}
+
+void vidtv_psi_sdt_table_destroy(struct vidtv_psi_table_sdt *sdt)
+{
+	struct vidtv_psi_table_sdt_service *curr_service = sdt->service;
+	struct vidtv_psi_table_sdt_service *tmp_service  = NULL;
+	struct vidtv_psi_desc *curr_desc = (sdt->service) ?
+					   sdt->service->descriptor : NULL;
+	struct vidtv_psi_desc *tmp_desc = NULL;
+
+	while (curr_service) {
+		curr_desc = curr_service->descriptor;
+
+		while (curr_desc) {
+			/* clear all descriptors for the service */
+			tmp_desc  = curr_desc;
+			curr_desc = curr_desc->next;
+			vidtv_psi_desc_destroy(tmp_desc);
+			kfree(tmp_desc);
+		}
+
+		/* then clear the current service */
+		tmp_service  = curr_service;
+		curr_service = curr_service->next;
+		kfree(tmp_service);
+	}
+}
+
+struct vidtv_psi_table_sdt_service
+*vidtv_psi_sdt_service_init(struct vidtv_psi_table_sdt_service *head,
+			    u16 service_id)
+{
+	/*
+	 * if 'head' is attached to a table, caller should recompute
+	 * the section length afterwards at some point
+	 */
+	struct vidtv_psi_table_sdt_service *service;
+
+	service = kzalloc(sizeof(*service), GFP_KERNEL);
+
+	/*
+	 * ETSI 300 468: this is a 16bit field which serves as a label to
+	 * identify this service from any other service within the TS.
+	 * The service id is the same as the program number in the
+	 * corresponding program_map_section
+	 */
+	service->service_id            = service_id;
+	service->EIT_schedule          = 0x0;         /* TODO */
+	service->EIT_present_following = 0x0;         /* TODO */
+	service->reserved              = 0x3f;        /* all bits on */
+	service->free_CA_mode          = 0x0;         /* not scrambled */
+	service->running_status        = RUNNING;
+
+	if (head) {
+		while (head->next)
+			head = head->next;
+
+		head->next = service;
+	}
+
+	return service;
+}
+
+void
+vidtv_psi_sdt_service_destroy(struct vidtv_psi_table_sdt_service *service)
+{
+	struct vidtv_psi_table_sdt_service *curr = service;
+	struct vidtv_psi_table_sdt_service *tmp  = NULL;
+
+	while (curr) {
+		tmp  = curr;
+		curr = curr->next;
+		kfree(tmp);
+	}
+}
+
+void
+vidtv_psi_sdt_service_assign(struct vidtv_psi_table_sdt *sdt,
+			     struct vidtv_psi_table_sdt_service *service)
+{
+	struct vidtv_psi_table_sdt_service *temp = sdt->service;
+
+	sdt->service = service;
+
+	/* recompute section length */
+	vidtv_psi_sdt_table_comp_sec_len(sdt);
+
+	/* reassign if the new size is too big */
+	if (sdt->header.section_length > MAX_SECTION_LEN)
+		vidtv_psi_sdt_service_assign(sdt, temp);
+	else
+		vidtv_psi_sdt_service_destroy(temp);
+}
+
+void
+vidtv_psi_pmt_create_sec_for_each_pat_entry(struct vidtv_psi_table_pat *pat,
+					    struct vidtv_psi_table_pmt sec[])
+
+{
+	/*
+	 * PMTs contain information about programs. For each program,
+	 * there is one PMT section. This function will create a section
+	 * for each program found in the PAT
+	 */
+	struct vidtv_psi_table_pat_program *program = pat->program;
+	u32    i                                    = 0;
+
+	while (program) {
+		vidtv_psi_pmt_table_init(&sec[i],
+					 false,
+					 sec[i].header.id,
+					 0);
+
+		++i;
+		program = program->next;
+	}
+}
diff --git a/drivers/media/test-drivers/vidtv/vidtv_psi.h b/drivers/media/test-drivers/vidtv/vidtv_psi.h
new file mode 100644
index 0000000000000..c5c8c143f0e4a
--- /dev/null
+++ b/drivers/media/test-drivers/vidtv/vidtv_psi.h
@@ -0,0 +1,357 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This file contains the logic to work with MPEG Program-Specific Information.
+ * These are defined both in ISO/IEC 13818-1 (systems) and ETSI EN 300 468.
+ * PSI is carried in the form of table structures, and although each table might
+ * technically be broken into one or more sections, we do not do this here,
+ * hence 'table' and 'section' are interchangeable for us.
+ *
+ * This code currently supports three tables: PAT, PMT and SDT. These are the
+ * bare minimum to get userspace to recognize our MPEG transport stream. It can
+ * be extended to support more PSI tables in the future.
+ *
+ * A note on endianness: MPEG layout is big-endian, therefore:
+ * - All fields spanning more than a byte must undergo 'cpu_to_beXX()' before
+ * serialization. These convertions are done in the *_write_into() functions.
+ *
+ * - All byte sized bitfields must have their ordering reversed if
+ *  __LITTLE_ENDIAN_BITFIELD is defined.
+ *
+ * Written by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
+ */
+
+#ifndef VIDTV_PSI_H
+#define VIDTV_PSI_H
+
+#include <linux/types.h>
+#include <asm/byteorder.h>
+
+/*
+ * all section lengths start immediately after the 'section_length' field
+ * see ISO/IEC 13818-1 : 2000 and ETSI EN 300 468 V 1.10.1 for
+ * reference
+ */
+#define PAT_LEN_UNTIL_LAST_SECTION_NUMBER 5
+#define PMT_LEN_UNTIL_PROGRAM_INFO_LENGTH 9
+#define SDT_LEN_UNTIL_RESERVED_FOR_FUTURE_USE 8
+#define MAX_SECTION_LEN 1021
+#define VIDTV_PAT_PID 0
+#define VIDTV_SDT_PID 0x0011
+
+enum vidtv_psi_descriptors {
+	REGISTRATION_DESCRIPTOR	= 0x05,
+	SERVICE_DESCRIPTOR = 0x48,
+};
+
+enum vidtv_psi_stream_types {
+	/* see ISO/IEC 13818-1 2000 p. 48 */
+	STREAM_PRIVATE_DATA = 0x06,
+};
+
+struct vidtv_psi_desc {
+	u8 type;
+	u8 length;
+	struct vidtv_psi_desc *next;
+	u8 data[];
+} __packed;
+
+struct vidtv_psi_desc_service {
+	u8 type;
+	u8 length;
+	struct vidtv_psi_desc *next;
+
+	u8 service_type;
+	char *name;
+	char *name_emph;
+	char *provider;
+	char *provider_emph;
+} __packed;
+
+struct vidtv_psi_desc_registration {
+	u8 type;
+	u8 length;
+	struct vidtv_psi_desc *next;
+
+	/*
+	 * The format_identifier is a 32-bit value obtained from a Registration
+	 * Authority as designated by ISO/IEC JTC 1/SC 29.
+	 */
+	u32 format_identifier;
+	/*
+	 * The meaning of additional_identification_info bytes, if any, are
+	 * defined by the assignee of that format_identifier, and once defined
+	 * they shall not change.
+	 */
+	u8 additional_identification_info[];
+} __packed;
+
+struct vidtv_psi_table_header {
+	u8  table_id;
+	union {
+		u16 bitfield;
+		struct {
+			u8  syntax:1;
+			u8  zero:1;
+			u8  one:2;
+			u16 section_length:12;
+		} __packed;
+	} __packed;
+
+	u16 id;			/* TS ID */
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	u8  current_next:1;
+	u8  version:5;
+	u8  one2:2;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	u8  one2:2;
+	u8  version:5;
+	u8  current_next:1;
+#else
+#error  "Please fix <asm/byteorder.h>"
+#endif
+	u8  section_id;		/* section_number */
+	u8  last_section;		/* last_section_number */
+} __packed;
+
+struct vidtv_psi_table_pat_program {
+	u16 service_id;
+	union {
+		u16 bitfield;
+		struct {
+			u8  reserved:3;
+			u16 pid:13;
+		} __packed;
+	} __packed;
+	struct vidtv_psi_table_pat_program *next;
+} __packed;
+
+struct vidtv_psi_table_pat {
+	struct vidtv_psi_table_header header;
+	u16 programs;
+	struct vidtv_psi_table_pat_program *program;
+} __packed;
+
+struct vidtv_psi_table_sdt_service {
+	u16 service_id;
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	u8 EIT_present_following:1;
+	u8 EIT_schedule:1;
+	u8 reserved:6;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	u8 reserved:6;
+	u8 EIT_schedule:1;
+	u8 EIT_present_following:1;
+#else
+#error  "Please fix <asm/byteorder.h>"
+#endif
+	union {
+		u16 bitfield;
+		struct {
+			u16 running_status:3;
+			u16 free_CA_mode:1;
+			u16 desc_length:12;
+		} __packed;
+	} __packed;
+	struct vidtv_psi_desc *descriptor;
+	struct vidtv_psi_table_sdt_service *next;
+} __packed;
+
+struct vidtv_psi_table_sdt {
+	struct vidtv_psi_table_header header;
+	u16 network_id; /* original_network_id */
+	u8  reserved;
+	struct vidtv_psi_table_sdt_service *service;
+} __packed;
+
+enum service_running_status {
+	RUNNING,
+};
+
+enum service_type {
+	/* see ETSI EN 300 468 v1.15.1 p. 77 */
+	DIGITAL_TELEVISION_SERVICE = 0x1,
+};
+
+struct vidtv_psi_table_pmt_stream {
+	u8 type;
+	union {
+		u16 bitfield;
+		struct {
+			u16 reserved:3;
+			u16 elementary_pid:13;
+		} __packed;
+	} __packed;
+	union {
+		u16 bitfield2;
+		struct {
+			u16 reserved2:4;
+			u16 zero:2;
+			u16 desc_length:10;
+		} __packed;
+	} __packed;
+	struct vidtv_psi_desc *descriptor;
+	struct vidtv_psi_table_pmt_stream *next;
+} __packed;
+
+struct vidtv_psi_table_pmt {
+	struct vidtv_psi_table_header header;
+	union {
+		u16 bitfield;
+		struct {
+			u16 reserved2:3;
+			u16 pcr_pid:13;
+		} __packed;
+	} __packed;
+
+	union {
+		u16 bitfield2;
+		struct {
+			u16 reserved3:4;
+			u16 zero3:2;
+			u16 desc_length:10; /* program_info_length */
+		} __packed;
+	} __packed;
+	struct vidtv_psi_desc *descriptor;
+	struct vidtv_psi_table_pmt_stream *stream;
+} __packed;
+
+struct psi_write_args {
+	void *dest_buf; /* the buffer to write into */
+	void *from;
+	size_t len; /* how much to write */
+	u32 dest_offset; /* where to start writing in the buffer */
+	u16 pid; /* TS packet ID */
+	bool new_psi_section; /* set when starting a table section */
+	u8 *continuity_counter; /* TS: incremented on every new packet */
+	bool is_crc; /* set when writing the CRC at the end */
+	u32 dest_buf_sz; /* protect against overflow if not zero */
+};
+
+struct desc_write_args {
+	void *dest_buf;
+	u32 dest_offset;
+	struct vidtv_psi_desc *desc;
+	u16 pid;
+	u8 *continuity_counter;
+	u32 dest_buf_sz;
+};
+
+struct crc32_write_args {
+	void *dest_buf;
+	u32 dest_offset;
+	u16 pid;
+	u8 *continuity_counter;
+	u32 dest_buf_sz;
+};
+
+struct header_write_args {
+	void *dest_buf;
+	u32 dest_offset;
+	struct vidtv_psi_table_header *h;
+	u16 pid;
+	u8 *continuity_counter;
+	u32 dest_buf_sz;
+};
+
+struct vidtv_psi_desc *vidtv_psi_desc_init(struct vidtv_psi_desc *head,
+					   u8 type,
+					   u8 length);
+
+void vidtv_psi_pat_table_init(struct vidtv_psi_table_pat *pat,
+			      bool update_version_num,
+			      u16 transport_stream_id);
+
+struct vidtv_psi_table_pat_program*
+vidtv_psi_pat_program_init(struct vidtv_psi_table_pat_program *head,
+			   u16 service_id,
+			   u16 pid);
+
+struct vidtv_psi_table_pmt_stream*
+vidtv_psi_pmt_stream_init(struct vidtv_psi_table_pmt_stream *head,
+			  enum vidtv_psi_stream_types stream_type,
+			  u16 es_pid);
+
+void vidtv_psi_pmt_table_init(struct vidtv_psi_table_pmt *pmt,
+			      bool update_version_num,
+			      u16 program_number,
+			      u16 pcr_pid);
+
+void
+vidtv_psi_sdt_table_init(struct vidtv_psi_table_sdt *sdt,
+			 bool update_version_num,
+			 u16 transport_stream_id);
+
+struct vidtv_psi_table_sdt_service*
+vidtv_psi_sdt_service_init(struct vidtv_psi_table_sdt_service *head,
+			   u16 service_id);
+
+void
+vidtv_psi_desc_destroy(struct vidtv_psi_desc *desc);
+
+void
+vidtv_psi_pat_program_destroy(struct vidtv_psi_table_pat_program *p);
+
+void
+vidtv_psi_pat_table_destroy(struct vidtv_psi_table_pat *p);
+
+void
+vidtv_psi_pmt_stream_destroy(struct vidtv_psi_table_pmt_stream *s);
+
+void
+vidtv_psi_pmt_table_destroy(struct vidtv_psi_table_pmt *pmt);
+
+void
+vidtv_psi_sdt_table_destroy(struct vidtv_psi_table_sdt *sdt);
+
+void
+vidtv_psi_sdt_service_destroy(struct vidtv_psi_table_sdt_service *service);
+
+void
+vidtv_psi_desc_destroy(struct vidtv_psi_desc *desc);
+
+void
+vidtv_psi_pat_program_destroy(struct vidtv_psi_table_pat_program *p);
+
+void
+vidtv_psi_sdt_service_assign(struct vidtv_psi_table_sdt *sdt,
+			     struct vidtv_psi_table_sdt_service *service);
+
+void vidtv_psi_desc_assign(struct vidtv_psi_desc **to,
+			   struct vidtv_psi_desc *desc);
+
+void vidtv_psi_pat_program_assign(struct vidtv_psi_table_pat *pat,
+				  struct vidtv_psi_table_pat_program *p);
+
+void vidtv_psi_pmt_stream_assign(struct vidtv_psi_table_pmt *pmt,
+				 struct vidtv_psi_table_pmt_stream *s);
+void
+vidtv_psi_pmt_create_sec_for_each_pat_entry(struct vidtv_psi_table_pat *pat,
+					    struct vidtv_psi_table_pmt *sec);
+
+u16 vidtv_psi_pmt_get_pid(struct vidtv_psi_table_pmt *section,
+			  struct vidtv_psi_table_pat *pat);
+
+void vidtv_psi_pat_table_comp_sec_len(struct vidtv_psi_table_pat *pat);
+void vidtv_psi_pmt_table_comp_sec_len(struct vidtv_psi_table_pmt *pmt);
+void vidtv_psi_sdt_table_comp_sec_len(struct vidtv_psi_table_sdt *sdt);
+
+u32 vidtv_psi_pat_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_pat *pat,
+			     u32 buf_sz,
+			     u8 *continuity_counter);
+
+u32 vidtv_psi_sdt_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_sdt *sdt,
+			     u32 buf_sz,
+			     u8 *continuity_counter);
+
+u32 vidtv_psi_pmt_write_into(char *buf,
+			     u32 offset,
+			     struct vidtv_psi_table_pmt *pmt,
+			     u16 pid,
+			     u32 buf_sz,
+			     u8 *continuity_counter);
+
+#endif // VIDTV_PSI_H
-- 
2.26.2