From 548e5ae0bd572509ee49e3684a20a3fa696181cb Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Wed, 7 Oct 2015 16:11:03 -0300 Subject: [PATCH] [media] DocBook: document the other structs/enums of demux.h Document the following data types: struct dmx_ts_feed struct dmx_section_filter struct dmx_section_feed enum dmx_frontend_source struct dmx_frontend Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb-core/demux.h | 97 ++++++++++++++++++++++++++++++---- 1 file changed, 88 insertions(+), 9 deletions(-) diff --git a/drivers/media/dvb-core/demux.h b/drivers/media/dvb-core/demux.h index 15b79bdee465..b344cad096cd 100644 --- a/drivers/media/dvb-core/demux.h +++ b/drivers/media/dvb-core/demux.h @@ -68,10 +68,24 @@ #define TS_DEMUX 8 /* in case TS_PACKET is set, send the TS to the demux device, not to the dvr device */ +/** + * struct dmx_ts_feed - Structure that contains a TS feed filter + * + * @is_filtering: Set to non-zero when filtering in progress + * @parent: pointer to struct dmx_demux + * @priv: pointer to private data of the API client + * @set: sets the TS filter + * @start_filtering: starts TS filtering + * @stop_filtering: stops TS filtering + * + * A TS feed is typically mapped to a hardware PID filter on the demux chip. + * Using this API, the client can set the filtering properties to start/stop + * filtering TS packets on a particular TS feed. + */ struct dmx_ts_feed { - int is_filtering; /* Set to non-zero when filtering in progress */ - struct dmx_demux *parent; /* Back-pointer */ - void *priv; /* Pointer to private data of the API client */ + int is_filtering; + struct dmx_demux *parent; + void *priv; int (*set) (struct dmx_ts_feed *feed, u16 pid, int type, @@ -86,6 +100,24 @@ struct dmx_ts_feed { /* Section reception */ /*--------------------------------------------------------------------------*/ +/** + * struct dmx_section_filter - Structure that describes a section filter + * + * @filter_value: Contains up to 16 bytes (128 bits) of the TS section header + * that will be matched by the section filter + * @filter_mask: Contains a 16 bytes (128 bits) filter mask with the bits + * specified by @filter_value that will be used on the filter + * match logic. + * @filter_mode: Contains a 16 bytes (128 bits) filter mode. + * @parent: Pointer to struct dmx_section_feed. + * @priv: Pointer to private data of the API client. + * + * + * The @filter_mask controls which bits of @filter_value are compared with + * the section headers/payload. On a binary value of 1 in filter_mask, the + * corresponding bits are compared. The filter only accepts sections that are + * equal to filter_value in all the tested bit positions. + */ struct dmx_section_filter { u8 filter_value [DMX_MAX_FILTER_SIZE]; u8 filter_mask [DMX_MAX_FILTER_SIZE]; @@ -94,18 +126,46 @@ struct dmx_section_filter { void* priv; /* Pointer to private data of the API client */ }; +/** + * struct dmx_section_feed - Structure that contains a section feed filter + * + * @is_filtering: Set to non-zero when filtering in progress + * @parent: pointer to struct dmx_demux + * @priv: pointer to private data of the API client + * @check_crc: If non-zero, check the CRC values of filtered sections. + * @set: sets the section filter + * @allocate_filter: This function is used to allocate a section filter on + * the demux. It should only be called when no filtering + * is in progress on this section feed. If a filter cannot + * be allocated, the function fails with -ENOSPC. + * @release_filter: This function releases all the resources of a + * previously allocated section filter. The function + * should not be called while filtering is in progress + * on this section feed. After calling this function, + * the caller should not try to dereference the filter + * pointer. + * @start_filtering: starts section filtering + * @stop_filtering: stops section filtering + * + * A TS feed is typically mapped to a hardware PID filter on the demux chip. + * Using this API, the client can set the filtering properties to start/stop + * filtering TS packets on a particular TS feed. + */ struct dmx_section_feed { - int is_filtering; /* Set to non-zero when filtering in progress */ - struct dmx_demux* parent; /* Back-pointer */ - void* priv; /* Pointer to private data of the API client */ + int is_filtering; + struct dmx_demux* parent; + void* priv; int check_crc; + + /* private: Used internally at dvb_demux.c */ u32 crc_val; u8 *secbuf; u8 secbuf_base[DMX_MAX_SECFEED_SIZE]; u16 secbufp, seclen, tsfeedp; + /* public: */ int (*set) (struct dmx_section_feed* feed, u16 pid, size_t circular_buffer_size, @@ -138,15 +198,34 @@ typedef int (*dmx_section_cb) ( const u8 * buffer1, /* DVB Front-End */ /*--------------------------------------------------------------------------*/ +/** + * enum dmx_frontend_source - Used to identify the type of frontend + * + * @DMX_MEMORY_FE: The source of the demux is memory. It means that + * the MPEG-TS to be filtered comes from userspace, + * via write() syscall. + * + * @DMX_FRONTEND_0: The source of the demux is a frontend connected + * to the demux. + */ enum dmx_frontend_source { DMX_MEMORY_FE, DMX_FRONTEND_0, }; +/** + * struct dmx_frontend - Structure that lists the frontends associated with + * a demux + * + * @connectivity_list: List of front-ends that can be connected to a + * particular demux; + * @source: Type of the frontend. + * + * FIXME: this structure should likely be replaced soon by some + * media-controller based logic. + */ struct dmx_frontend { - struct list_head connectivity_list; /* List of front-ends that can - be connected to a particular - demux */ + struct list_head connectivity_list; enum dmx_frontend_source source; }; -- 2.39.2