| .. SPDX-License-Identifier: GPL-2.0 |
| |
| .. include:: <isonum.txt> |
| |
| |
| The SI476x Driver |
| ================= |
| |
| Copyright |copy| 2013 Andrey Smirnov <andrew.smirnov@gmail.com> |
| |
| TODO for the driver |
| ------------------- |
| |
| - According to the SiLabs' datasheet it is possible to update the |
| firmware of the radio chip in the run-time, thus bringing it to the |
| most recent version. Unfortunately I couldn't find any mentioning of |
| the said firmware update for the old chips that I tested the driver |
| against, so for chips like that the driver only exposes the old |
| functionality. |
| |
| |
| Parameters exposed over debugfs |
| ------------------------------- |
| SI476x allow user to get multiple characteristics that can be very |
| useful for EoL testing/RF performance estimation, parameters that have |
| very little to do with V4L2 subsystem. Such parameters are exposed via |
| debugfs and can be accessed via regular file I/O operations. |
| |
| The drivers exposes following files: |
| |
| * /sys/kernel/debug/<device-name>/acf |
| This file contains ACF(Automatically Controlled Features) status |
| information. The contents of the file is binary data of the |
| following layout: |
| |
| .. tabularcolumns:: |p{7ex}|p{12ex}|L| |
| |
| ============= ============== ==================================== |
| Offset Name Description |
| ============= ============== ==================================== |
| 0x00 blend_int Flag, set when stereo separation has |
| crossed below the blend threshold |
| 0x01 hblend_int Flag, set when HiBlend cutoff |
| frequency is lower than threshold |
| 0x02 hicut_int Flag, set when HiCut cutoff |
| frequency is lower than threshold |
| 0x03 chbw_int Flag, set when channel filter |
| bandwidth is less than threshold |
| 0x04 softmute_int Flag indicating that softmute |
| attenuation has increased above |
| softmute threshold |
| 0x05 smute 0 - Audio is not soft muted |
| 1 - Audio is soft muted |
| 0x06 smattn Soft mute attenuation level in dB |
| 0x07 chbw Channel filter bandwidth in kHz |
| 0x08 hicut HiCut cutoff frequency in units of |
| 100Hz |
| 0x09 hiblend HiBlend cutoff frequency in units |
| of 100 Hz |
| 0x10 pilot 0 - Stereo pilot is not present |
| 1 - Stereo pilot is present |
| 0x11 stblend Stereo blend in % |
| ============= ============== ==================================== |
| |
| |
| * /sys/kernel/debug/<device-name>/rds_blckcnt |
| This file contains statistics about RDS receptions. It's binary data |
| has the following layout: |
| |
| .. tabularcolumns:: |p{7ex}|p{12ex}|L| |
| |
| ============= ============== ==================================== |
| Offset Name Description |
| ============= ============== ==================================== |
| 0x00 expected Number of expected RDS blocks |
| 0x02 received Number of received RDS blocks |
| 0x04 uncorrectable Number of uncorrectable RDS blocks |
| ============= ============== ==================================== |
| |
| * /sys/kernel/debug/<device-name>/agc |
| This file contains information about parameters pertaining to |
| AGC(Automatic Gain Control) |
| |
| The layout is: |
| |
| .. tabularcolumns:: |p{7ex}|p{12ex}|L| |
| |
| ============= ============== ==================================== |
| Offset Name Description |
| ============= ============== ==================================== |
| 0x00 mxhi 0 - FM Mixer PD high threshold is |
| not tripped |
| 1 - FM Mixer PD high threshold is |
| tripped |
| 0x01 mxlo ditto for FM Mixer PD low |
| 0x02 lnahi ditto for FM LNA PD high |
| 0x03 lnalo ditto for FM LNA PD low |
| 0x04 fmagc1 FMAGC1 attenuator resistance |
| (see datasheet for more detail) |
| 0x05 fmagc2 ditto for FMAGC2 |
| 0x06 pgagain PGA gain in dB |
| 0x07 fmwblang FM/WB LNA Gain in dB |
| ============= ============== ==================================== |
| |
| * /sys/kernel/debug/<device-name>/rsq |
| This file contains information about parameters pertaining to |
| RSQ(Received Signal Quality) |
| |
| The layout is: |
| |
| .. tabularcolumns:: |p{7ex}|p{12ex}|p{60ex}| |
| |
| ============= ============== ==================================== |
| Offset Name Description |
| ============= ============== ==================================== |
| 0x00 multhint 0 - multipath value has not crossed |
| the Multipath high threshold |
| 1 - multipath value has crossed |
| the Multipath high threshold |
| 0x01 multlint ditto for Multipath low threshold |
| 0x02 snrhint 0 - received signal's SNR has not |
| crossed high threshold |
| 1 - received signal's SNR has |
| crossed high threshold |
| 0x03 snrlint ditto for low threshold |
| 0x04 rssihint ditto for RSSI high threshold |
| 0x05 rssilint ditto for RSSI low threshold |
| 0x06 bltf Flag indicating if seek command |
| reached/wrapped seek band limit |
| 0x07 snr_ready Indicates that SNR metrics is ready |
| 0x08 rssiready ditto for RSSI metrics |
| 0x09 injside 0 - Low-side injection is being used |
| 1 - High-side injection is used |
| 0x10 afcrl Flag indicating if AFC rails |
| 0x11 valid Flag indicating if channel is valid |
| 0x12 readfreq Current tuned frequency |
| 0x14 freqoff Signed frequency offset in units of |
| 2ppm |
| 0x15 rssi Signed value of RSSI in dBuV |
| 0x16 snr Signed RF SNR in dB |
| 0x17 issi Signed Image Strength Signal |
| indicator |
| 0x18 lassi Signed Low side adjacent Channel |
| Strength indicator |
| 0x19 hassi ditto fpr High side |
| 0x20 mult Multipath indicator |
| 0x21 dev Frequency deviation |
| 0x24 assi Adjacent channel SSI |
| 0x25 usn Ultrasonic noise indicator |
| 0x26 pilotdev Pilot deviation in units of 100 Hz |
| 0x27 rdsdev ditto for RDS |
| 0x28 assidev ditto for ASSI |
| 0x29 strongdev Frequency deviation |
| 0x30 rdspi RDS PI code |
| ============= ============== ==================================== |
| |
| * /sys/kernel/debug/<device-name>/rsq_primary |
| This file contains information about parameters pertaining to |
| RSQ(Received Signal Quality) for primary tuner only. Layout is as |
| the one above. |
