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

[karo-tx-linux.git] / Documentation / DocBook / media / v4l / media-types.xml

diff --git a/Documentation/DocBook/media/v4l/media-types.xml b/Documentation/DocBook/media/v4l/media-types.xml
index 1af3842509105ea45fd815ad953781d901b03bfe..751c3d0271036544dae44457fdab0f8767830ef7 100644 (file)
--- a/Documentation/DocBook/media/v4l/media-types.xml
+++ b/Documentation/DocBook/media/v4l/media-types.xml
@@ -84,7 +84,34 @@
          </row>
          <row>
            <entry><constant>MEDIA_ENT_F_TUNER</constant></entry>
-           <entry>Digital TV, analog TV, radio and/or software radio tuner.</entry>
+           <entry>Digital TV, analog TV, radio and/or software radio tuner,
+                  with consists on a PLL tuning stage that converts radio
+                  frequency (RF) signal into an Intermediate Frequency (IF).
+                  Modern tuners have internally IF-PLL decoders for audio
+                  and video, but older models have those stages implemented
+                  on separate entities.
+           </entry>
+         </row>
+         <row>
+           <entry><constant>MEDIA_ENT_F_IF_VID_DECODER</constant></entry>
+           <entry>IF-PLL video decoder. It receives the IF from a PLL
+                  and decodes the analog TV video signal. This is commonly
+                  found on some very old analog tuners, like Philips MK3
+                  designs. They all contain a tda9887 (or some software
+                  compatible similar chip, like tda9885). Those devices
+                  use a different I2C address than the tuner PLL.
+           </entry>
+         </row>
+         <row>
+           <entry><constant>MEDIA_ENT_F_IF_AUD_DECODER</constant></entry>
+           <entry>IF-PLL sound decoder. It receives the IF from a PLL
+                  and decodes the analog TV audio signal. This is commonly
+                  found on some very old analog hardware, like Micronas
+                  msp3400, Philips tda9840, tda985x, etc. Those devices
+                  use a different I2C address than the tuner PLL and
+                  should be controlled together with the IF-PLL video
+                  decoder.
+           </entry>
          </row>
        </tbody>
       </tgroup>