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Diffstat (limited to 'Documentation/DocBook/device-drivers.tmpl')
-rw-r--r-- | Documentation/DocBook/device-drivers.tmpl | 84 |
1 files changed, 16 insertions, 68 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl index 42a2d85..7b3fcc5 100644 --- a/Documentation/DocBook/device-drivers.tmpl +++ b/Documentation/DocBook/device-drivers.tmpl @@ -238,78 +238,26 @@ X!Isound/sound_firmware.c !Iinclude/media/videobuf2-memops.h </sect1> <sect1><title>Digital TV (DVB) devices</title> -!Idrivers/media/dvb-core/dvb_ca_en50221.h -!Idrivers/media/dvb-core/dvb_frontend.h + <sect1><title>Digital TV Common functions</title> !Idrivers/media/dvb-core/dvb_math.h !Idrivers/media/dvb-core/dvb_ringbuffer.h !Idrivers/media/dvb-core/dvbdev.h - <sect1><title>Digital TV Demux API</title> - <para>The kernel demux API 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 API is named - <constant>demux.h</constant> and located in - <constant>drivers/media/dvb-core</constant>.</para> - - <para>The demux API 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 API, it receives a pointer to the API of that - resource.</para> - <para>Each demux receives its TS input from a DVB front-end or from - memory, as set via this demux API. In a system with more than one - front-end, the API 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 API only controls front-ends regarding to their connections - with demuxes; the APIs used to set the other front-end parameters, - such as tuning, are not defined in this document.</para> - <para>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 <constant>dmx_demux</constant>. For example, - a demux interface might support Section filtering, but not PES - filtering. The API 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”.</para> - <para>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.</para> - <para>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 API function - is called from network device code, the function must not sleep. - </para> - </sect1> - - <section id="demux_callback_api"> - <title>Demux Callback API</title> - <para>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.</para> - <para>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.</para> - <para>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.</para> - <para>This mechanism is implemented by - <link linkend='API-dmx-ts-cb'>dmx_ts_cb()</link> and - <link linkend='API-dmx-section-cb'>dmx_section_cb()</link>.</para> - </section> - + </sect1> + <sect1><title>Digital TV Frontend kABI</title> +!Pdrivers/media/dvb-core/dvb_frontend.h Digital TV Frontend +!Idrivers/media/dvb-core/dvb_frontend.h + </sect1> + <sect1><title>Digital TV Demux kABI</title> +!Pdrivers/media/dvb-core/demux.h Digital TV Demux + <sect1><title>Demux Callback API</title> +!Pdrivers/media/dvb-core/demux.h Demux Callback + </sect1> !Idrivers/media/dvb-core/demux.h - </sect1> + </sect1> + <sect1><title>Digital TV Conditional Access kABI</title> +!Idrivers/media/dvb-core/dvb_ca_en50221.h + </sect1> + </sect1> <sect1><title>Remote Controller devices</title> !Iinclude/media/rc-core.h !Iinclude/media/lirc_dev.h |