diff options
author | Hans Verkuil <hverkuil@xs4all.nl> | 2006-01-09 15:25:39 -0200 |
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committer | Mauro Carvalho Chehab <mchehab@brturbo.com.br> | 2006-01-09 15:25:39 -0200 |
commit | a544521ef06ee7b8a3d82fa29627401196fda77a (patch) | |
tree | 602154d687748d1f3e9255d50cdf36b679add581 /include | |
parent | 66e33dee9e3062b1045afe23c4b8714c1004668c (diff) |
V4L/DVB (3245): Added some comments about multiple tuner support.
- Added some comments to make clearer how to use ioctl api to handle
multiple tuners at the same board.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Diffstat (limited to 'include')
-rw-r--r-- | include/media/tuner.h | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/include/media/tuner.h b/include/media/tuner.h index aa91ce35915..c5f034ecb00 100644 --- a/include/media/tuner.h +++ b/include/media/tuner.h @@ -150,10 +150,26 @@ enum tuner_mode { T_STANDBY = 1 << 31 }; +/* Older boards only had a single tuner device. Nowadays multiple tuner + devices may be present on a single board. Using TUNER_SET_TYPE_ADDR + to pass the tuner_setup structure it is possible to setup each tuner + device in turn. + + Since multiple devices may be present it is no longer sufficient to + send a command to a single i2c device. Instead you should broadcast + the command to all i2c devices. + + By setting the mode_mask correctly you can select which commands are + accepted by a specific tuner device. For example, set mode_mask to + T_RADIO if the device is a radio-only tuner. That specific tuner will + only accept commands when the tuner is in radio mode and ignore them + when the tuner is set to TV mode. + */ + struct tuner_setup { - unsigned short addr; - unsigned int type; - unsigned int mode_mask; + unsigned short addr; /* I2C address */ + unsigned int type; /* Tuner type */ + unsigned int mode_mask; /* Allowed tuner modes */ }; struct tuner { |