Merge remote-tracking branch 'spi/for-next'

[karo-tx-linux.git] / Documentation / DocBook / device-drivers.tmpl

diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index 1d6008d51b5552f4be9a71f4bc4e568b004fb1eb..42a2d8593e39cd15acbab6ace23ed08e5c33a313 100644 (file)
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -221,6 +221,9 @@ X!Isound/sound_firmware.c
      <title>Media Devices</title>
 
      <sect1><title>Video2Linux devices</title>
+!Iinclude/media/tuner.h
+!Iinclude/media/tuner-types.h
+!Iinclude/media/tveeprom.h
 !Iinclude/media/v4l2-async.h
 !Iinclude/media/v4l2-ctrls.h
 !Iinclude/media/v4l2-dv-timings.h
@@ -231,6 +234,7 @@ X!Isound/sound_firmware.c
 !Iinclude/media/v4l2-of.h
 !Iinclude/media/v4l2-subdev.h
 !Iinclude/media/videobuf2-core.h
+!Iinclude/media/videobuf2-v4l2.h
 !Iinclude/media/videobuf2-memops.h
      </sect1>
      <sect1><title>Digital TV (DVB) devices</title>
@@ -239,15 +243,82 @@ X!Isound/sound_firmware.c
 !Idrivers/media/dvb-core/dvb_math.h
 !Idrivers/media/dvb-core/dvb_ringbuffer.h
 !Idrivers/media/dvb-core/dvbdev.h
-     </sect1>
-     <sect1><title>Remote Controller devices</title>
+       <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 &#8220;function is not available&#8221;.</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
+       &#8220;bottom half&#8221; 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>
+
+!Idrivers/media/dvb-core/demux.h
+    </sect1>
+    <sect1><title>Remote Controller devices</title>
 !Iinclude/media/rc-core.h
-     </sect1>
-     <sect1><title>Media Controller devices</title>
+!Iinclude/media/lirc_dev.h
+    </sect1>
+    <sect1><title>Media Controller devices</title>
 !Iinclude/media/media-device.h
 !Iinclude/media/media-devnode.h
 !Iinclude/media/media-entity.h
-     </sect1>
+    </sect1>
 
   </chapter>