diff options
Diffstat (limited to 'drivers/media/test-drivers/vidtv/vidtv_psi.h')
| -rw-r--r-- | drivers/media/test-drivers/vidtv/vidtv_psi.h | 577 |
1 files changed, 577 insertions, 0 deletions
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 000000000000..3f962cc78278 --- /dev/null +++ b/drivers/media/test-drivers/vidtv/vidtv_psi.h @@ -0,0 +1,577 @@ +/* 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 vidtv. + * + * 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. + * + * Copyright (C) 2020 Daniel W. S. Almeida + */ + +#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 /* mandated by the specs */ +#define VIDTV_SDT_PID 0x0011 /* mandated by the specs */ + +enum vidtv_psi_descriptors { + REGISTRATION_DESCRIPTOR = 0x05, /* See ISO/IEC 13818-1 section 2.6.8 */ + SERVICE_DESCRIPTOR = 0x48, /* See ETSI EN 300 468 section 6.2.33 */ +}; + +enum vidtv_psi_stream_types { + STREAM_PRIVATE_DATA = 0x06, /* see ISO/IEC 13818-1 2000 p. 48 */ +}; + +/** + * struct vidtv_psi_desc - A generic PSI descriptor type. + * The descriptor length is an 8-bit field specifying the total number of bytes of the data portion + * of the descriptor following the byte defining the value of this field. + */ +struct vidtv_psi_desc { + struct vidtv_psi_desc *next; + u8 type; + u8 length; + u8 data[]; +} __packed; + +/** + * struct vidtv_psi_desc_service - Service descriptor. + * See ETSI EN 300 468 section 6.2.33. + */ +struct vidtv_psi_desc_service { + struct vidtv_psi_desc *next; + u8 type; + u8 length; + + u8 service_type; + u8 provider_name_len; + char *provider_name; + u8 service_name_len; + char *service_name; +} __packed; + +/** + * struct vidtv_psi_desc_registration - A registration descriptor. + * See ISO/IEC 13818-1 section 2.6.8 + */ +struct vidtv_psi_desc_registration { + struct vidtv_psi_desc *next; + u8 type; + u8 length; + + /* + * The format_identifier is a 32-bit value obtained from a Registration + * Authority as designated by ISO/IEC JTC 1/SC 29. + */ + __be32 format_id; + /* + * 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 - A header that is present for all PSI tables. + */ +struct vidtv_psi_table_header { + u8 table_id; + + __be16 bitfield; /* syntax: 1, zero: 1, one: 2, section_length: 13 */ + + __be16 id; /* TS ID */ + u8 current_next:1; + u8 version:5; + u8 one2:2; + u8 section_id; /* section_number */ + u8 last_section; /* last_section_number */ +} __packed; + +/** + * struct vidtv_psi_table_pat_program - A single program in the PAT + * See ISO/IEC 13818-1 : 2000 p.43 + */ +struct vidtv_psi_table_pat_program { + __be16 service_id; + __be16 bitfield; /* reserved: 3, program_map_pid/network_pid: 13 */ + struct vidtv_psi_table_pat_program *next; +} __packed; + +/** + * struct vidtv_psi_table_pat - The Program Allocation Table (PAT) + * See ISO/IEC 13818-1 : 2000 p.43 + */ +struct vidtv_psi_table_pat { + struct vidtv_psi_table_header header; + u16 programs; /* Included by libdvbv5, not part of the table and not actually serialized */ + struct vidtv_psi_table_pat_program *program; +} __packed; + +/** + * struct vidtv_psi_table_sdt_service - Represents a service in the SDT. + * see ETSI EN 300 468 v1.15.1 section 5.2.3. + */ +struct vidtv_psi_table_sdt_service { + __be16 service_id; + u8 EIT_present_following:1; + u8 EIT_schedule:1; + u8 reserved:6; + __be16 bitfield; /* running_status: 3, free_ca:1, desc_loop_len:12 */ + struct vidtv_psi_desc *descriptor; + struct vidtv_psi_table_sdt_service *next; +} __packed; + +/** + * struct vidtv_psi_table_sdt - Represents the Service Description Table + * see ETSI EN 300 468 v1.15.1 section 5.2.3. + */ + +struct vidtv_psi_table_sdt { + struct vidtv_psi_table_header header; + __be16 network_id; /* original_network_id */ + u8 reserved; + struct vidtv_psi_table_sdt_service *service; +} __packed; + +/** + * enum service_running_status - Status of a SDT service. + * see ETSI EN 300 468 v1.15.1 section 5.2.3 table 6. + */ +enum service_running_status { + RUNNING = 0x4, +}; + +/** + * enum service_type - The type of a SDT service. + * see ETSI EN 300 468 v1.15.1 section 6.2.33, table 81. + */ +enum service_type { + /* see ETSI EN 300 468 v1.15.1 p. 77 */ + DIGITAL_TELEVISION_SERVICE = 0x1, +}; + +/** + * struct vidtv_psi_table_pmt_stream - A single stream in the PMT. + * See ISO/IEC 13818-1 : 2000 p.46. + */ +struct vidtv_psi_table_pmt_stream { + u8 type; + __be16 bitfield; /* reserved: 3, elementary_pid: 13 */ + __be16 bitfield2; /*reserved: 4, zero: 2, desc_length: 10 */ + struct vidtv_psi_desc *descriptor; + struct vidtv_psi_table_pmt_stream *next; +} __packed; + +/** + * struct vidtv_psi_table_pmt - The Program Map Table (PMT). + * See ISO/IEC 13818-1 : 2000 p.46. + */ +struct vidtv_psi_table_pmt { + struct vidtv_psi_table_header header; + __be16 bitfield; /* reserved:3, pcr_pid: 13 */ + __be16 bitfield2; /* reserved: 4, zero: 2, desc_len: 10 */ + struct vidtv_psi_desc *descriptor; + struct vidtv_psi_table_pmt_stream *stream; +} __packed; + +/** + * struct psi_write_args - Arguments for the PSI packetizer. + * @dest_buf: The buffer to write into. + * @from: PSI data to be copied. + * @len: How much to write. + * @dest_offset: where to start writing in the dest_buffer. + * @pid: TS packet ID. + * @new_psi_section: Set when starting a table section. + * @continuity_counter: Incremented on every new packet. + * @is_crc: Set when writing the CRC at the end. + * @dest_buf_sz: The size of the dest_buffer + * @crc: a pointer to store the crc for this chunk + */ +struct psi_write_args { + void *dest_buf; + void *from; + size_t len; + u32 dest_offset; + u16 pid; + bool new_psi_section; + u8 *continuity_counter; + bool is_crc; + u32 dest_buf_sz; + u32 *crc; +}; + +/** + * struct desc_write_args - Arguments in order to write a descriptor. + * @dest_buf: The buffer to write into. + * @dest_offset: where to start writing in the dest_buffer. + * @desc: A pointer to the descriptor + * @pid: TS packet ID. + * @continuity_counter: Incremented on every new packet. + * @dest_buf_sz: The size of the dest_buffer + * @crc: a pointer to store the crc for this chunk + */ +struct desc_write_args { + void *dest_buf; + u32 dest_offset; + struct vidtv_psi_desc *desc; + u16 pid; + u8 *continuity_counter; + u32 dest_buf_sz; + u32 *crc; +}; + +/** + * struct crc32_write_args - Arguments in order to write the CRC at the end of + * the PSI tables. + * @dest_buf: The buffer to write into. + * @dest_offset: where to start writing in the dest_buffer. + * @crc: the CRC value to write + * @pid: TS packet ID. + * @continuity_counter: Incremented on every new packet. + * @dest_buf_sz: The size of the dest_buffer + */ +struct crc32_write_args { + void *dest_buf; + u32 dest_offset; + __be32 crc; + u16 pid; + u8 *continuity_counter; + u32 dest_buf_sz; +}; + +/** + * struct header_write_args - Arguments in order to write the common table + * header + * @dest_buf: The buffer to write into. + * @dest_offset: where to start writing in the dest_buffer. + * @h: a pointer to the header. + * @pid: TS packet ID. + * @continuity_counter: Incremented on every new packet. + * @dest_buf_sz: The size of the dest_buffer + * @crc: a pointer to store the crc for this chunk + */ +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; + u32 *crc; +}; + +struct vidtv_psi_desc_service *vidtv_psi_service_desc_init(struct vidtv_psi_desc *head, + enum service_type service_type, + char *service_name, + char *provider_name); + +struct vidtv_psi_desc_registration +*vidtv_psi_registration_desc_init(struct vidtv_psi_desc *head, + __be32 format_id, + u8 *additional_ident_info, + u32 additional_info_len); + +struct vidtv_psi_table_pat_program +*vidtv_psi_pat_program_init(struct vidtv_psi_table_pat_program *head, + u16 service_id, + u16 program_map_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); + +struct vidtv_psi_table_pat *vidtv_psi_pat_table_init(u16 transport_stream_id); + +struct vidtv_psi_table_pmt *vidtv_psi_pmt_table_init(u16 program_number, + u16 pcr_pid); + +struct vidtv_psi_table_sdt *vidtv_psi_sdt_table_init(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); + +/** + * vidtv_psi_sdt_service_assign - Assigns the service loop to the SDT. + * @sdt: The SDT to assign to. + * @service: The service loop (one or more services) + * + * This will free the previous service loop in the table. + * This will assign ownership of the service loop to the table, i.e. the table + * will free this service loop when a call to its destroy function is made. + */ +void +vidtv_psi_sdt_service_assign(struct vidtv_psi_table_sdt *sdt, + struct vidtv_psi_table_sdt_service *service); + +/** + * vidtv_psi_desc_assign - Assigns a descriptor loop at some point + * @to: Where to assign this descriptor loop to + * @desc: The descriptor loop that will be assigned. + * + * This will free the loop in 'to', if any. + */ +void vidtv_psi_desc_assign(struct vidtv_psi_desc **to, + struct vidtv_psi_desc *desc); + +/** + * vidtv_psi_pmt_desc_assign - Assigns a descriptor loop at some point in a PMT section. + * @pmt: The PMT section that will contain the descriptor loop + * @to: Where in the PMT to assign this descriptor loop to + * @desc: The descriptor loop that will be assigned. + * + * This will free the loop in 'to', if any. + * This will assign ownership of the loop to the table, i.e. the table + * will free this loop when a call to its destroy function is made. + */ +void vidtv_pmt_desc_assign(struct vidtv_psi_table_pmt *pmt, + struct vidtv_psi_desc **to, + struct vidtv_psi_desc *desc); + +/** + * vidtv_psi_sdt_desc_assign - Assigns a descriptor loop at some point in a SDT. + * @sdt: The SDT that will contain the descriptor loop + * @to: Where in the PMT to assign this descriptor loop to + * @desc: The descriptor loop that will be assigned. + * + * This will free the loop in 'to', if any. + * This will assign ownership of the loop to the table, i.e. the table + * will free this loop when a call to its destroy function is made. + */ +void vidtv_sdt_desc_assign(struct vidtv_psi_table_sdt *sdt, + struct vidtv_psi_desc **to, + struct vidtv_psi_desc *desc); + +/** + * vidtv_psi_pat_program_assign - Assigns the program loop to the PAT. + * @pat: The PAT to assign to. + * @p: The program loop (one or more programs) + * + * This will free the previous program loop in the table. + * This will assign ownership of the program loop to the table, i.e. the table + * will free this program loop when a call to its destroy function is made. + */ +void vidtv_psi_pat_program_assign(struct vidtv_psi_table_pat *pat, + struct vidtv_psi_table_pat_program *p); + +/** + * vidtv_psi_pmt_stream_assign - Assigns the stream loop to the PAT. + * @pmt: The PMT to assign to. + * @s: The stream loop (one or more streams) + * + * This will free the previous stream loop in the table. + * This will assign ownership of the stream loop to the table, i.e. the table + * will free this stream loop when a call to its destroy function is made. + */ +void vidtv_psi_pmt_stream_assign(struct vidtv_psi_table_pmt *pmt, + struct vidtv_psi_table_pmt_stream *s); + +struct vidtv_psi_desc *vidtv_psi_desc_clone(struct vidtv_psi_desc *desc); + +/** + * vidtv_psi_create_sec_for_each_pat_entry - Create a PMT section for each + * program found in the PAT + * @pat: The PAT to look for programs. + * @s: The stream loop (one or more streams) + * @pcr_pid: packet ID for the PCR to be used for the program described in this + * PMT section + */ +struct vidtv_psi_table_pmt** +vidtv_psi_pmt_create_sec_for_each_pat_entry(struct vidtv_psi_table_pat *pat, u16 pcr_pid); + +/** + * vidtv_psi_pmt_get_pid - Get the TS PID for a PMT section. + * @section: The PMT section whose PID we want to retrieve. + * @pat: The PAT table to look into. + * + * Returns: the TS PID for 'section' + */ +u16 vidtv_psi_pmt_get_pid(struct vidtv_psi_table_pmt *section, + struct vidtv_psi_table_pat *pat); + +/** + * vidtv_psi_pat_table_update_sec_len - Recompute and update the PAT section length. + * @pat: The PAT whose length is to be updated. + * + * This will traverse the table and accumulate the length of its components, + * which is then used to replace the 'section_length' field. + * + * If section_length > MAX_SECTION_LEN, the operation fails. + */ +void vidtv_psi_pat_table_update_sec_len(struct vidtv_psi_table_pat *pat); + +/** + * vidtv_psi_pmt_table_update_sec_len - Recompute and update the PMT section length. + * @pmt: The PMT whose length is to be updated. + * + * This will traverse the table and accumulate the length of its components, + * which is then used to replace the 'section_length' field. + * + * If section_length > MAX_SECTION_LEN, the operation fails. + */ +void vidtv_psi_pmt_table_update_sec_len(struct vidtv_psi_table_pmt *pmt); + +/** + * vidtv_psi_sdt_table_update_sec_len - Recompute and update the SDT section length. + * @sdt: The SDT whose length is to be updated. + * + * This will traverse the table and accumulate the length of its components, + * which is then used to replace the 'section_length' field. + * + * If section_length > MAX_SECTION_LEN, the operation fails. + */ +void vidtv_psi_sdt_table_update_sec_len(struct vidtv_psi_table_sdt *sdt); + +/** + * struct vidtv_psi_pat_write_args - Arguments for writing a PAT table + * @buf: The destination buffer. + * @offset: The offset into the destination buffer. + * @pat: A pointer to the PAT. + * @buf_sz: The size of the destination buffer. + * @continuity_counter: A pointer to the CC. Incremented on every new packet. + * + */ +struct vidtv_psi_pat_write_args { + char *buf; + u32 offset; + struct vidtv_psi_table_pat *pat; + u32 buf_sz; + u8 *continuity_counter; +}; + +/** + * vidtv_psi_pat_write_into - Write PAT as MPEG-TS packets into a buffer. + * @args: An instance of struct vidtv_psi_pat_write_args + * + * This function writes the MPEG TS packets for a PAT table into a buffer. + * Calling code will usually generate the PAT via a call to its init function + * and thus is responsible for freeing it. + * + * Return: The number of bytes written into the buffer. This is NOT + * equal to the size of the PAT, since more space is needed for TS headers during TS + * encapsulation. + */ +u32 vidtv_psi_pat_write_into(struct vidtv_psi_pat_write_args args); + +/** + * struct vidtv_psi_sdt_write_args - Arguments for writing a SDT table + * @buf: The destination buffer. + * @offset: The offset into the destination buffer. + * @sdt: A pointer to the SDT. + * @buf_sz: The size of the destination buffer. + * @continuity_counter: A pointer to the CC. Incremented on every new packet. + * + */ + +struct vidtv_psi_sdt_write_args { + char *buf; + u32 offset; + struct vidtv_psi_table_sdt *sdt; + u32 buf_sz; + u8 *continuity_counter; +}; + +/** + * vidtv_psi_sdt_write_into - Write SDT as MPEG-TS packets into a buffer. + * @args: an instance of struct vidtv_psi_sdt_write_args + * + * This function writes the MPEG TS packets for a SDT table into a buffer. + * Calling code will usually generate the SDT via a call to its init function + * and thus is responsible for freeing it. + * + * Return: The number of bytes written into the buffer. This is NOT + * equal to the size of the SDT, since more space is needed for TS headers during TS + * encapsulation. + */ +u32 vidtv_psi_sdt_write_into(struct vidtv_psi_sdt_write_args args); + +/** + * struct vidtv_psi_pmt_write_args - Arguments for writing a PMT section + * @buf: The destination buffer. + * @offset: The offset into the destination buffer. + * @pmt: A pointer to the PMT. + * @buf_sz: The size of the destination buffer. + * @continuity_counter: A pointer to the CC. Incremented on every new packet. + * + */ +struct vidtv_psi_pmt_write_args { + char *buf; + u32 offset; + struct vidtv_psi_table_pmt *pmt; + u16 pid; + u32 buf_sz; + u8 *continuity_counter; + u16 pcr_pid; +}; + +/** + * vidtv_psi_pmt_write_into - Write PMT as MPEG-TS packets into a buffer. + * @args: an instance of struct vidtv_psi_pmt_write_args + * + * This function writes the MPEG TS packets for a PMT section into a buffer. + * Calling code will usually generate the PMT section via a call to its init function + * and thus is responsible for freeing it. + * + * Return: The number of bytes written into the buffer. This is NOT + * equal to the size of the PMT section, since more space is needed for TS headers + * during TS encapsulation. + */ +u32 vidtv_psi_pmt_write_into(struct vidtv_psi_pmt_write_args args); + +/** + * vidtv_psi_find_pmt_sec - Finds the PMT section for 'program_num' + * @pmt_sections: The sections to look into. + * @nsections: The number of sections. + * @program_num: The 'program_num' from PAT pointing to a PMT section. + * + * Return: A pointer to the PMT, if found, or NULL. + */ +struct vidtv_psi_table_pmt *vidtv_psi_find_pmt_sec(struct vidtv_psi_table_pmt **pmt_sections, + u16 nsections, + u16 program_num); + +u16 vidtv_psi_get_pat_program_pid(struct vidtv_psi_table_pat_program *p); +u16 vidtv_psi_pmt_stream_get_elem_pid(struct vidtv_psi_table_pmt_stream *s); + +#endif // VIDTV_PSI_H |