Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) .. _rf-tuner-controls:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) **************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) RF Tuner Control Reference
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) **************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) The RF Tuner (RF_TUNER) class includes controls for common features of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) devices having RF tuner.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) In this context, RF tuner is radio receiver circuit between antenna and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) demodulator. It receives radio frequency (RF) from the antenna and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) converts that received signal to lower intermediate frequency (IF) or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) baseband frequency (BB). Tuners that could do baseband output are often
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) called Zero-IF tuners. Older tuners were typically simple PLL tuners
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) inside a metal box, while newer ones are highly integrated chips
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) without a metal box "silicon tuners". These controls are mostly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) applicable for new feature rich silicon tuners, just because older
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) tuners does not have much adjustable features.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) For more information about RF tuners see
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) `Tuner (radio) <http://en.wikipedia.org/wiki/Tuner_%28radio%29>`__
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) and `RF front end <http://en.wikipedia.org/wiki/RF_front_end>`__
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) from Wikipedia.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) .. _rf-tuner-control-id:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) RF_TUNER Control IDs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) ====================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) ``V4L2_CID_RF_TUNER_CLASS (class)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)     The RF_TUNER class descriptor. Calling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)     :ref:`VIDIOC_QUERYCTRL` for this control will
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)     return a description of this control class.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) ``V4L2_CID_RF_TUNER_BANDWIDTH_AUTO (boolean)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)     Enables/disables tuner radio channel bandwidth configuration. In
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)     automatic mode bandwidth configuration is performed by the driver.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) ``V4L2_CID_RF_TUNER_BANDWIDTH (integer)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)     Filter(s) on tuner signal path are used to filter signal according
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)     to receiving party needs. Driver configures filters to fulfill
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)     desired bandwidth requirement. Used when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)     V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not set. Unit is in Hz. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)     range and step are driver-specific.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) ``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO (boolean)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)     Enables/disables LNA automatic gain control (AGC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) ``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO (boolean)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)     Enables/disables mixer automatic gain control (AGC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) ``V4L2_CID_RF_TUNER_IF_GAIN_AUTO (boolean)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)     Enables/disables IF automatic gain control (AGC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) ``V4L2_CID_RF_TUNER_RF_GAIN (integer)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)     The RF amplifier is the very first amplifier on the receiver signal
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)     path, just right after the antenna input. The difference between the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)     LNA gain and the RF gain in this document is that the LNA gain is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)     integrated in the tuner chip while the RF gain is a separate chip.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)     There may be both RF and LNA gain controls in the same device. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)     range and step are driver-specific.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) ``V4L2_CID_RF_TUNER_LNA_GAIN (integer)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)     LNA (low noise amplifier) gain is first gain stage on the RF tuner
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)     signal path. It is located very close to tuner antenna input. Used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)     when ``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO`` is not set. See
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)     ``V4L2_CID_RF_TUNER_RF_GAIN`` to understand how RF gain and LNA gain
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)     differs from the each others. The range and step are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)     driver-specific.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) ``V4L2_CID_RF_TUNER_MIXER_GAIN (integer)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)     Mixer gain is second gain stage on the RF tuner signal path. It is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)     located inside mixer block, where RF signal is down-converted by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)     mixer. Used when ``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO`` is not set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)     The range and step are driver-specific.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) ``V4L2_CID_RF_TUNER_IF_GAIN (integer)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)     IF gain is last gain stage on the RF tuner signal path. It is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)     located on output of RF tuner. It controls signal level of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)     intermediate frequency output or baseband output. Used when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)     ``V4L2_CID_RF_TUNER_IF_GAIN_AUTO`` is not set. The range and step
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)     are driver-specific.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) ``V4L2_CID_RF_TUNER_PLL_LOCK (boolean)``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)     Is synthesizer PLL locked? RF tuner is receiving given frequency
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)     when that control is set. This is a read-only control.