• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1.. include:: <isonum.txt>
2
3
4The SI476x Driver
5=================
6
7Copyright |copy| 2013 Andrey Smirnov <andrew.smirnov@gmail.com>
8
9TODO for the driver
10-------------------
11
12- According to the SiLabs' datasheet it is possible to update the
13  firmware of the radio chip in the run-time, thus bringing it to the
14  most recent version. Unfortunately I couldn't find any mentioning of
15  the said firmware update for the old chips that I tested the driver
16  against, so for chips like that the driver only exposes the old
17  functionality.
18
19
20Parameters exposed over debugfs
21-------------------------------
22SI476x allow user to get multiple characteristics that can be very
23useful for EoL testing/RF performance estimation, parameters that have
24very little to do with V4L2 subsystem. Such parameters are exposed via
25debugfs and can be accessed via regular file I/O operations.
26
27The drivers exposes following files:
28
29* /sys/kernel/debug/<device-name>/acf
30  This file contains ACF(Automatically Controlled Features) status
31  information. The contents of the file is binary data of the
32  following layout:
33
34  .. tabularcolumns:: |p{7ex}|p{12ex}|L|
35
36  =============  ==============   ====================================
37  Offset	 Name		  Description
38  =============  ==============   ====================================
39  0x00		 blend_int	  Flag, set when stereo separation has
40				  crossed below the blend threshold
41  0x01		 hblend_int	  Flag, set when HiBlend cutoff
42				  frequency is lower than threshold
43  0x02		 hicut_int	  Flag, set when HiCut cutoff
44				  frequency is lower than threshold
45  0x03		 chbw_int	  Flag, set when channel filter
46				  bandwidth is less than threshold
47  0x04		 softmute_int	  Flag indicating that softmute
48				  attenuation has increased above
49				  softmute threshold
50  0x05		 smute		  0 - Audio is not soft muted
51				  1 - Audio is soft muted
52  0x06		 smattn		  Soft mute attenuation level in dB
53  0x07		 chbw		  Channel filter bandwidth in kHz
54  0x08		 hicut		  HiCut cutoff frequency in units of
55				  100Hz
56  0x09		 hiblend	  HiBlend cutoff frequency in units
57				  of 100 Hz
58  0x10		 pilot		  0 - Stereo pilot is not present
59				  1 - Stereo pilot is present
60  0x11		 stblend	  Stereo blend in %
61  =============  ==============   ====================================
62
63
64* /sys/kernel/debug/<device-name>/rds_blckcnt
65  This file contains statistics about RDS receptions. It's binary data
66  has the following layout:
67
68  .. tabularcolumns:: |p{7ex}|p{12ex}|L|
69
70  =============  ==============   ====================================
71  Offset	 Name		  Description
72  =============  ==============   ====================================
73  0x00		 expected	  Number of expected RDS blocks
74  0x02		 received	  Number of received RDS blocks
75  0x04		 uncorrectable	  Number of uncorrectable RDS blocks
76  =============  ==============   ====================================
77
78* /sys/kernel/debug/<device-name>/agc
79  This file contains information about parameters pertaining to
80  AGC(Automatic Gain Control)
81
82  The layout is:
83
84  .. tabularcolumns:: |p{7ex}|p{12ex}|L|
85
86  =============  ==============   ====================================
87  Offset	 Name		  Description
88  =============  ==============   ====================================
89  0x00		 mxhi		  0 - FM Mixer PD high threshold is
90				  not tripped
91				  1 - FM Mixer PD high threshold is
92				  tripped
93  0x01		 mxlo		  ditto for FM Mixer PD low
94  0x02		 lnahi		  ditto for FM LNA PD high
95  0x03		 lnalo		  ditto for FM LNA PD low
96  0x04		 fmagc1		  FMAGC1 attenuator resistance
97				  (see datasheet for more detail)
98  0x05		 fmagc2		  ditto for FMAGC2
99  0x06		 pgagain	  PGA gain in dB
100  0x07		 fmwblang	  FM/WB LNA Gain in dB
101  =============  ==============   ====================================
102
103* /sys/kernel/debug/<device-name>/rsq
104  This file contains information about parameters pertaining to
105  RSQ(Received Signal Quality)
106
107  The layout is:
108
109  .. tabularcolumns:: |p{7ex}|p{12ex}|p{60ex}|
110
111  =============  ==============   ====================================
112  Offset	 Name		  Description
113  =============  ==============   ====================================
114  0x00		 multhint	  0 - multipath value has not crossed
115				  the Multipath high threshold
116				  1 - multipath value has crossed
117				  the Multipath high threshold
118  0x01		 multlint	  ditto for Multipath low threshold
119  0x02		 snrhint	  0 - received signal's SNR has not
120				  crossed high threshold
121				  1 - received signal's SNR has
122				  crossed high threshold
123  0x03		 snrlint	  ditto for low threshold
124  0x04		 rssihint	  ditto for RSSI high threshold
125  0x05		 rssilint	  ditto for RSSI low threshold
126  0x06		 bltf		  Flag indicating if seek command
127				  reached/wrapped seek band limit
128  0x07		 snr_ready	  Indicates that SNR metrics is ready
129  0x08		 rssiready	  ditto for RSSI metrics
130  0x09		 injside	  0 - Low-side injection is being used
131				  1 - High-side injection is used
132  0x10		 afcrl		  Flag indicating if AFC rails
133  0x11		 valid		  Flag indicating if channel is valid
134  0x12		 readfreq	  Current tuned frequency
135  0x14		 freqoff	  Signed frequency offset in units of
136				  2ppm
137  0x15		 rssi		  Signed value of RSSI in dBuV
138  0x16		 snr		  Signed RF SNR in dB
139  0x17		 issi		  Signed Image Strength Signal
140				  indicator
141  0x18		 lassi		  Signed Low side adjacent Channel
142				  Strength indicator
143  0x19		 hassi		  ditto fpr High side
144  0x20		 mult		  Multipath indicator
145  0x21		 dev		  Frequency deviation
146  0x24		 assi		  Adjacent channel SSI
147  0x25		 usn		  Ultrasonic noise indicator
148  0x26		 pilotdev	  Pilot deviation in units of 100 Hz
149  0x27		 rdsdev		  ditto for RDS
150  0x28		 assidev	  ditto for ASSI
151  0x29		 strongdev	  Frequency deviation
152  0x30		 rdspi		  RDS PI code
153  =============  ==============   ====================================
154
155* /sys/kernel/debug/<device-name>/rsq_primary
156  This file contains information about parameters pertaining to
157  RSQ(Received Signal Quality) for primary tuner only. Layout is as
158  the one above.
159