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-rw-r--r--Documentation/DocBook/media/v4l/media-types.xml29
-rw-r--r--include/uapi/linux/media.h17
2 files changed, 43 insertions, 3 deletions
diff --git a/Documentation/DocBook/media/v4l/media-types.xml b/Documentation/DocBook/media/v4l/media-types.xml
index 1af384250910..751c3d027103 100644
--- 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>
diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
index 5dbb208e5451..c9eb42a6c021 100644
--- a/include/uapi/linux/media.h
+++ b/include/uapi/linux/media.h
@@ -89,6 +89,15 @@ struct media_device_info {
#define MEDIA_ENT_F_IO_SWRADIO (MEDIA_ENT_F_BASE + 33)
/*
+ * Analog TV IF-PLL decoders
+ *
+ * It is a responsibility of the master/bridge drivers to create links
+ * for MEDIA_ENT_F_IF_VID_DECODER and MEDIA_ENT_F_IF_AUD_DECODER.
+ */
+#define MEDIA_ENT_F_IF_VID_DECODER (MEDIA_ENT_F_BASE + 41)
+#define MEDIA_ENT_F_IF_AUD_DECODER (MEDIA_ENT_F_BASE + 42)
+
+/*
* Don't touch on those. The ranges MEDIA_ENT_F_OLD_BASE and
* MEDIA_ENT_F_OLD_SUBDEV_BASE are kept to keep backward compatibility
* with the legacy v1 API.The number range is out of range by purpose:
@@ -107,8 +116,12 @@ struct media_device_info {
#define MEDIA_ENT_F_LENS (MEDIA_ENT_F_OLD_SUBDEV_BASE + 3)
#define MEDIA_ENT_F_ATV_DECODER (MEDIA_ENT_F_OLD_SUBDEV_BASE + 4)
/*
- * It is a responsibility of the entity drivers to add connectors and links
- * for the tuner entities.
+ * It is a responsibility of the master/bridge drivers to add connectors
+ * and links for MEDIA_ENT_F_TUNER. Please notice that some old tuners
+ * may require the usage of separate I2C chips to decode analog TV signals,
+ * when the master/bridge chipset doesn't have its own TV standard decoder.
+ * On such cases, the IF-PLL staging is mapped via one or two entities:
+ * MEDIA_ENT_F_IF_VID_DECODER and/or MEDIA_ENT_F_IF_AUD_DECODER.
*/
#define MEDIA_ENT_F_TUNER (MEDIA_ENT_F_OLD_SUBDEV_BASE + 5)