1*059b1c5bSMauro Carvalho Chehab.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 254f38fcaSMauro Carvalho Chehab 354f38fcaSMauro Carvalho Chehab.. _rf-tuner-controls: 454f38fcaSMauro Carvalho Chehab 554f38fcaSMauro Carvalho Chehab************************** 654f38fcaSMauro Carvalho ChehabRF Tuner Control Reference 754f38fcaSMauro Carvalho Chehab************************** 854f38fcaSMauro Carvalho Chehab 954f38fcaSMauro Carvalho ChehabThe RF Tuner (RF_TUNER) class includes controls for common features of 1054f38fcaSMauro Carvalho Chehabdevices having RF tuner. 1154f38fcaSMauro Carvalho Chehab 1254f38fcaSMauro Carvalho ChehabIn this context, RF tuner is radio receiver circuit between antenna and 1354f38fcaSMauro Carvalho Chehabdemodulator. It receives radio frequency (RF) from the antenna and 1454f38fcaSMauro Carvalho Chehabconverts that received signal to lower intermediate frequency (IF) or 1554f38fcaSMauro Carvalho Chehabbaseband frequency (BB). Tuners that could do baseband output are often 1654f38fcaSMauro Carvalho Chehabcalled Zero-IF tuners. Older tuners were typically simple PLL tuners 1754f38fcaSMauro Carvalho Chehabinside a metal box, while newer ones are highly integrated chips 1854f38fcaSMauro Carvalho Chehabwithout a metal box "silicon tuners". These controls are mostly 1954f38fcaSMauro Carvalho Chehabapplicable for new feature rich silicon tuners, just because older 2054f38fcaSMauro Carvalho Chehabtuners does not have much adjustable features. 2154f38fcaSMauro Carvalho Chehab 2254f38fcaSMauro Carvalho ChehabFor more information about RF tuners see 2354f38fcaSMauro Carvalho Chehab`Tuner (radio) <http://en.wikipedia.org/wiki/Tuner_%28radio%29>`__ 2454f38fcaSMauro Carvalho Chehaband `RF front end <http://en.wikipedia.org/wiki/RF_front_end>`__ 2554f38fcaSMauro Carvalho Chehabfrom Wikipedia. 2654f38fcaSMauro Carvalho Chehab 2754f38fcaSMauro Carvalho Chehab 2854f38fcaSMauro Carvalho Chehab.. _rf-tuner-control-id: 2954f38fcaSMauro Carvalho Chehab 3054f38fcaSMauro Carvalho ChehabRF_TUNER Control IDs 3154f38fcaSMauro Carvalho Chehab==================== 3254f38fcaSMauro Carvalho Chehab 3354f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_CLASS (class)`` 3454f38fcaSMauro Carvalho Chehab The RF_TUNER class descriptor. Calling 3554f38fcaSMauro Carvalho Chehab :ref:`VIDIOC_QUERYCTRL` for this control will 3654f38fcaSMauro Carvalho Chehab return a description of this control class. 3754f38fcaSMauro Carvalho Chehab 3854f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_BANDWIDTH_AUTO (boolean)`` 3954f38fcaSMauro Carvalho Chehab Enables/disables tuner radio channel bandwidth configuration. In 4054f38fcaSMauro Carvalho Chehab automatic mode bandwidth configuration is performed by the driver. 4154f38fcaSMauro Carvalho Chehab 4254f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_BANDWIDTH (integer)`` 4354f38fcaSMauro Carvalho Chehab Filter(s) on tuner signal path are used to filter signal according 4454f38fcaSMauro Carvalho Chehab to receiving party needs. Driver configures filters to fulfill 4554f38fcaSMauro Carvalho Chehab desired bandwidth requirement. Used when 4654f38fcaSMauro Carvalho Chehab V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not set. Unit is in Hz. The 4754f38fcaSMauro Carvalho Chehab range and step are driver-specific. 4854f38fcaSMauro Carvalho Chehab 4954f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO (boolean)`` 5054f38fcaSMauro Carvalho Chehab Enables/disables LNA automatic gain control (AGC) 5154f38fcaSMauro Carvalho Chehab 5254f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO (boolean)`` 5354f38fcaSMauro Carvalho Chehab Enables/disables mixer automatic gain control (AGC) 5454f38fcaSMauro Carvalho Chehab 5554f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_IF_GAIN_AUTO (boolean)`` 5654f38fcaSMauro Carvalho Chehab Enables/disables IF automatic gain control (AGC) 5754f38fcaSMauro Carvalho Chehab 5854f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_RF_GAIN (integer)`` 5954f38fcaSMauro Carvalho Chehab The RF amplifier is the very first amplifier on the receiver signal 6054f38fcaSMauro Carvalho Chehab path, just right after the antenna input. The difference between the 6154f38fcaSMauro Carvalho Chehab LNA gain and the RF gain in this document is that the LNA gain is 6254f38fcaSMauro Carvalho Chehab integrated in the tuner chip while the RF gain is a separate chip. 6354f38fcaSMauro Carvalho Chehab There may be both RF and LNA gain controls in the same device. The 6454f38fcaSMauro Carvalho Chehab range and step are driver-specific. 6554f38fcaSMauro Carvalho Chehab 6654f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_LNA_GAIN (integer)`` 6754f38fcaSMauro Carvalho Chehab LNA (low noise amplifier) gain is first gain stage on the RF tuner 6854f38fcaSMauro Carvalho Chehab signal path. It is located very close to tuner antenna input. Used 6954f38fcaSMauro Carvalho Chehab when ``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO`` is not set. See 7054f38fcaSMauro Carvalho Chehab ``V4L2_CID_RF_TUNER_RF_GAIN`` to understand how RF gain and LNA gain 7154f38fcaSMauro Carvalho Chehab differs from the each others. The range and step are 7254f38fcaSMauro Carvalho Chehab driver-specific. 7354f38fcaSMauro Carvalho Chehab 7454f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_MIXER_GAIN (integer)`` 7554f38fcaSMauro Carvalho Chehab Mixer gain is second gain stage on the RF tuner signal path. It is 7654f38fcaSMauro Carvalho Chehab located inside mixer block, where RF signal is down-converted by the 7754f38fcaSMauro Carvalho Chehab mixer. Used when ``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO`` is not set. 7854f38fcaSMauro Carvalho Chehab The range and step are driver-specific. 7954f38fcaSMauro Carvalho Chehab 8054f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_IF_GAIN (integer)`` 8154f38fcaSMauro Carvalho Chehab IF gain is last gain stage on the RF tuner signal path. It is 8254f38fcaSMauro Carvalho Chehab located on output of RF tuner. It controls signal level of 8354f38fcaSMauro Carvalho Chehab intermediate frequency output or baseband output. Used when 8454f38fcaSMauro Carvalho Chehab ``V4L2_CID_RF_TUNER_IF_GAIN_AUTO`` is not set. The range and step 8554f38fcaSMauro Carvalho Chehab are driver-specific. 8654f38fcaSMauro Carvalho Chehab 8754f38fcaSMauro Carvalho Chehab``V4L2_CID_RF_TUNER_PLL_LOCK (boolean)`` 8854f38fcaSMauro Carvalho Chehab Is synthesizer PLL locked? RF tuner is receiving given frequency 8954f38fcaSMauro Carvalho Chehab when that control is set. This is a read-only control. 90