[alsa-devel] [RFCv1] Media Token API needs - Was: Re: [PATCH v2 5/6] sound/usb: pcm changes to use media token api

Mauro Carvalho Chehab mchehab at osg.samsung.com
Wed Oct 29 01:00:51 CET 2014


Em Tue, 28 Oct 2014 21:42:50 -0200
Mauro Carvalho Chehab <mchehab at osg.samsung.com> escreveu:

> Before starting with the description, this is the simplified diagram of
> a media device (without IR, eeprom and other beasts):

As reference, a more complete diagram would be:



                                                                +------------------+
                                                                |        IR        |
                                                                +------------------+
                                                                  |
                                                                  |
                                                                  v
                                                                +------------------+
                                                                |  IR POLL or DMA  |
                                                                +------------------+
                                                                  |
                                                                  |
                                                                  v
                                                                +------------------+
                                                                |  devnode input8  |
                                                                +------------------+

                             +------------------------------------+
                             v                                    |
                           +----------------+          +-------+-------------------+-----------+
                           |  demod_video   |  +-----> | tuner |     A/V switch    | composite |
                           +----------------+  |       +-------+-------------------+-----------+
                             |                 |                  |
                             |                 |                  |
                             v                 |                  v
     +--------------+-----+-----------------+  |                +------------------+
  +- |     dvb      | DMA |      analog     |  |                |   demod_audio    |
  |  +--------------+-----+-----------------+  |                +------------------+
  |    ^                     |                 |                  |
  |    +---------------+     |                 |                  |
  |                    |     v                 |                  v
  |  +--------------+  |   +----------------+  |                +------------------+
  +> | devnode dvr0 |  |   | devnode video0 |  |                |    audio DMA     |
     +--------------+  |   +----------------+  |                +------------------+
                       |                       |                  |
                       |                       |                  |
                       |                       |                  v
                       |                       |                +------------------+
                       |                       |                | devnode pcmC1D0c |
                       |                       |                +------------------+
                       |                       |
                       |                       |
                       |                       |
                       |                     +--------+--------+-------------------+
                       |                     | analog |  tuner |      digital      |
                       |                     +--------+--------+-------------------+
                       |                                          |
                       |                                          |
                       |                                          v
                       |                                        +------------------+
                       +--------------------------------------- |  digital_demux   |
                                                                +------------------+

Regards,
Mauro

-

Dot file for the above diagram:

digraph media_hardware {
  node [shape=record]
  DMA1[label = "<dvb> dvb | <dma> DMA | <video> analog"]
  DMA2[label = "audio DMA"]
  DMA3[label = "IR POLL or DMA"]
  tuner[label = "<analog> analog | <tuner> tuner | <digital> digital"]
  input[label = "<tuner> tuner | <switch> A/V switch | <composite> composite"]

  DMA1:video -> "devnode video0"
  DMA1:dvb -> "devnode dvr0"

  "digital_demux" -> DMA1:dvb
  demod_video -> DMA1:video

  tuner:digital -> "digital_demux"
  tuner:analog -> input:tuner

  input:switch -> demod_video
  input:switch -> demod_audio

  demod_audio -> DMA2
  DMA2 -> "devnode pcmC1D0c"

  IR -> DMA3
  DMA3 -> "devnode input8"
}


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