diff options
Diffstat (limited to 'drivers/media/dvb-core/demux.h')
| -rw-r--r-- | drivers/media/dvb-core/demux.h | 165 |
1 files changed, 51 insertions, 114 deletions
diff --git a/drivers/media/dvb-core/demux.h b/drivers/media/dvb-core/demux.h index 7f1dffef4353..4b4c1da20f4b 100644 --- a/drivers/media/dvb-core/demux.h +++ b/drivers/media/dvb-core/demux.h @@ -1,6 +1,10 @@ /* * demux.h * + * The Kernel Digital TV Demux kABI defines a driver-internal interface for + * registering low-level, hardware specific driver to a hardware independent + * demux layer. + * * Copyright (c) 2002 Convergence GmbH * * based on code: @@ -32,49 +36,6 @@ #include <linux/time.h> #include <linux/dvb/dmx.h> -/** - * DOC: Digital TV Demux - * - * The Kernel Digital TV Demux kABI defines a driver-internal interface for - * registering low-level, hardware specific driver to a hardware independent - * demux layer. It is only of interest for Digital TV device driver writers. - * The header file for this kABI is named demux.h and located in - * drivers/media/dvb-core. - * - * The demux kABI should be implemented for each demux in the system. It is - * used to select the TS source of a demux and to manage the demux resources. - * When the demux client allocates a resource via the demux kABI, it receives - * a pointer to the kABI of that resource. - * - * Each demux receives its TS input from a DVB front-end or from memory, as - * set via this demux kABI. In a system with more than one front-end, the kABI - * can be used to select one of the DVB front-ends as a TS source for a demux, - * unless this is fixed in the HW platform. - * - * The demux kABI only controls front-ends regarding to their connections with - * demuxes; the kABI used to set the other front-end parameters, such as - * tuning, are devined via the Digital TV Frontend kABI. - * - * The functions that implement the abstract interface demux should be defined - * static or module private and registered to the Demux core for external - * access. It is not necessary to implement every function in the struct - * &dmx_demux. For example, a demux interface might support Section filtering, - * but not PES filtering. The kABI client is expected to check the value of any - * function pointer before calling the function: the value of NULL means - * that the function is not available. - * - * Whenever the functions of the demux API modify shared data, the - * possibilities of lost update and race condition problems should be - * addressed, e.g. by protecting parts of code with mutexes. - * - * Note that functions called from a bottom half context must not sleep. - * Even a simple memory allocation without using %GFP_ATOMIC can result in a - * kernel thread being put to sleep if swapping is needed. For example, the - * Linux Kernel calls the functions of a network device interface from a - * bottom half context. Thus, if a demux kABI function is called from network - * device code, the function must not sleep. - */ - /* * Common definitions */ @@ -104,7 +65,7 @@ */ /** - * enum ts_filter_type - filter type bitmap for dmx_ts_feed.set() + * enum ts_filter_type - filter type bitmap for dmx_ts_feed.set\(\) * * @TS_PACKET: Send TS packets (188 bytes) to callback (default). * @TS_PAYLOAD_ONLY: In case TS_PACKET is set, only send the TS payload @@ -231,30 +192,6 @@ struct dmx_section_feed { }; /** - * DOC: Demux Callback - * - * This kernel-space API comprises the callback functions that deliver filtered - * data to the demux client. Unlike the other DVB kABIs, these functions are - * provided by the client and called from the demux code. - * - * The function pointers of this abstract interface are not packed into a - * structure as in the other demux APIs, because the callback functions are - * registered and used independent of each other. As an example, it is possible - * for the API client to provide several callback functions for receiving TS - * packets and no callbacks for PES packets or sections. - * - * The functions that implement the callback API need not be re-entrant: when - * a demux driver calls one of these functions, the driver is not allowed to - * call the function again before the original call returns. If a callback is - * triggered by a hardware interrupt, it is recommended to use the Linux - * bottom half mechanism or start a tasklet instead of making the callback - * function call directly from a hardware interrupt. - * - * This mechanism is implemented by dmx_ts_cb() and dmx_section_cb() - * callbacks. - */ - -/** * typedef dmx_ts_cb - DVB demux TS filter callback function prototype * * @buffer1: Pointer to the start of the filtered TS packets. @@ -402,7 +339,7 @@ struct dmx_frontend { * @DMX_SECTION_FILTERING: set if section filtering is supported; * @DMX_MEMORY_BASED_FILTERING: set if write() available. * - * Those flags are OR'ed in the &dmx_demux.&capabilities field + * Those flags are OR'ed in the &dmx_demux.capabilities field */ enum dmx_demux_caps { DMX_TS_FILTERING = 1, @@ -442,10 +379,10 @@ enum dmx_demux_caps { * @open is called and decrement it when @close is called. * The @demux function parameter contains a pointer to the demux API and * instance data. - * It returns - * 0 on success; - * -EUSERS, if maximum usage count was reached; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -EUSERS, if maximum usage count was reached; + * -EINVAL, on bad parameter. * * @close: This function reserves the demux for use by the caller and, if * necessary, initializes the demux. When the demux is no longer needed, @@ -455,10 +392,10 @@ enum dmx_demux_caps { * @open is called and decrement it when @close is called. * The @demux function parameter contains a pointer to the demux API and * instance data. - * It returns - * 0 on success; - * -ENODEV, if demux was not in use (e. g. no users); - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -ENODEV, if demux was not in use (e. g. no users); + * -EINVAL, on bad parameter. * * @write: This function provides the demux driver with a memory buffer * containing TS packets. Instead of receiving TS packets from the DVB @@ -473,12 +410,12 @@ enum dmx_demux_caps { * The @buf function parameter contains a pointer to the TS data in * kernel-space memory. * The @count function parameter contains the length of the TS data. - * It returns - * 0 on success; - * -ERESTARTSYS, if mutex lock was interrupted; - * -EINTR, if a signal handling is pending; - * -ENODEV, if demux was removed; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -ERESTARTSYS, if mutex lock was interrupted; + * -EINTR, if a signal handling is pending; + * -ENODEV, if demux was removed; + * -EINVAL, on bad parameter. * * @allocate_ts_feed: Allocates a new TS feed, which is used to filter the TS * packets carrying a certain PID. The TS feed normally corresponds to a @@ -489,11 +426,11 @@ enum dmx_demux_caps { * instance data. * The @callback function parameter contains a pointer to the callback * function for passing received TS packet. - * It returns - * 0 on success; - * -ERESTARTSYS, if mutex lock was interrupted; - * -EBUSY, if no more TS feeds is available; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -ERESTARTSYS, if mutex lock was interrupted; + * -EBUSY, if no more TS feeds is available; + * -EINVAL, on bad parameter. * * @release_ts_feed: Releases the resources allocated with @allocate_ts_feed. * Any filtering in progress on the TS feed should be stopped before @@ -502,9 +439,9 @@ enum dmx_demux_caps { * instance data. * The @feed function parameter contains a pointer to the TS feed API and * instance data. - * It returns - * 0 on success; - * -EINVAL on bad parameter. + * It returns: + * 0 on success; + * -EINVAL on bad parameter. * * @allocate_section_feed: Allocates a new section feed, i.e. a demux resource * for filtering and receiving sections. On platforms with hardware @@ -520,10 +457,10 @@ enum dmx_demux_caps { * instance data. * The @callback function parameter contains a pointer to the callback * function for passing received TS packet. - * It returns - * 0 on success; - * -EBUSY, if no more TS feeds is available; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -EBUSY, if no more TS feeds is available; + * -EINVAL, on bad parameter. * * @release_section_feed: Releases the resources allocated with * @allocate_section_feed, including allocated filters. Any filtering in @@ -533,9 +470,9 @@ enum dmx_demux_caps { * instance data. * The @feed function parameter contains a pointer to the TS feed API and * instance data. - * It returns - * 0 on success; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -EINVAL, on bad parameter. * * @add_frontend: Registers a connectivity between a demux and a front-end, * i.e., indicates that the demux can be connected via a call to @@ -549,9 +486,9 @@ enum dmx_demux_caps { * instance data. * The @frontend function parameter contains a pointer to the front-end * instance data. - * It returns - * 0 on success; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -EINVAL, on bad parameter. * * @remove_frontend: Indicates that the given front-end, registered by a call * to @add_frontend, can no longer be connected as a TS source by this @@ -565,10 +502,10 @@ enum dmx_demux_caps { * instance data. * The @frontend function parameter contains a pointer to the front-end * instance data. - * It returns - * 0 on success; - * -ENODEV, if the front-end was not found, - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -ENODEV, if the front-end was not found, + * -EINVAL, on bad parameter. * * @get_frontends: Provides the APIs of the front-ends that have been * registered for this demux. Any of the front-ends obtained with this @@ -592,17 +529,17 @@ enum dmx_demux_caps { * instance data. * The @frontend function parameter contains a pointer to the front-end * instance data. - * It returns - * 0 on success; - * -EINVAL, on bad parameter. + * It returns: + * 0 on success; + * -EINVAL, on bad parameter. * * @disconnect_frontend: Disconnects the demux and a front-end previously * connected by a @connect_frontend call. * The @demux function parameter contains a pointer to the demux API and * instance data. - * It returns - * 0 on success; - * -EINVAL on bad parameter. + * It returns: + * 0 on success; + * -EINVAL on bad parameter. * * @get_pes_pids: Get the PIDs for DMX_PES_AUDIO0, DMX_PES_VIDEO0, * DMX_PES_TELETEXT0, DMX_PES_SUBTITLE0 and DMX_PES_PCR0. @@ -610,9 +547,9 @@ enum dmx_demux_caps { * instance data. * The @pids function parameter contains an array with five u16 elements * where the PIDs will be stored. - * It returns - * 0 on success; - * -EINVAL on bad parameter. + * It returns: + * 0 on success; + * -EINVAL on bad parameter. */ struct dmx_demux { |