Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux...
[linux/fpc-iii.git] / Documentation / video4linux / si476x.txt
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1 SI476x Driver Readme
2 ------------------------------------------------
3         Copyright (C) 2013 Andrey Smirnov <andrew.smirnov@gmail.com>
5 TODO for the driver
6 ------------------------------
8 - According to the SiLabs' datasheet it is possible to update the
9   firmware of the radio chip in the run-time, thus bringing it to the
10   most recent version. Unfortunately I couldn't find any mentioning of
11   the said firmware update for the old chips that I tested the driver
12   against, so for chips like that the driver only exposes the old
13   functionality.
16 Parameters exposed over debugfs
17 -------------------------------
18 SI476x allow user to get multiple characteristics that can be very
19 useful for EoL testing/RF performance estimation, parameters that have
20 very little to do with V4L2 subsystem. Such parameters are exposed via
21 debugfs and can be accessed via regular file I/O operations.
23 The drivers exposes following files:
25 * /sys/kernel/debug/<device-name>/acf
26   This file contains ACF(Automatically Controlled Features) status
27   information. The contents of the file is binary data of the
28   following layout:
30   Offset        | Name          | Description
31   ====================================================================
32   0x00          | blend_int     | Flag, set when stereo separation has
33                 |               | crossed below the blend threshold
34   --------------------------------------------------------------------
35   0x01          | hblend_int    | Flag, set when HiBlend cutoff
36                 |               | frequency is lower than threshold
37   --------------------------------------------------------------------
38   0x02          | hicut_int     | Flag, set when HiCut cutoff
39                 |               | frequency is lower than threshold
40   --------------------------------------------------------------------
41   0x03          | chbw_int      | Flag, set when channel filter
42                 |               | bandwidth is less than threshold
43   --------------------------------------------------------------------
44   0x04          | softmute_int  | Flag indicating that softmute
45                 |               | attenuation has increased above
46                 |               | softmute threshold
47   --------------------------------------------------------------------
48   0x05          | smute         | 0 - Audio is not soft muted
49                 |               | 1 - Audio is soft muted
50   --------------------------------------------------------------------
51   0x06          | smattn        | Soft mute attenuation level in dB
52   --------------------------------------------------------------------
53   0x07          | chbw          | Channel filter bandwidth in kHz
54   --------------------------------------------------------------------
55   0x08          | hicut         | HiCut cutoff frequency in units of
56                 |               | 100Hz
57   --------------------------------------------------------------------
58   0x09          | hiblend       | HiBlend cutoff frequency in units
59                 |               | of 100 Hz
60   --------------------------------------------------------------------
61   0x10          | pilot         | 0 - Stereo pilot is not present
62                 |               | 1 - Stereo pilot is present
63   --------------------------------------------------------------------
64   0x11          | stblend       | Stereo blend in %
65   --------------------------------------------------------------------
68 * /sys/kernel/debug/<device-name>/rds_blckcnt
69   This file contains statistics about RDS receptions. It's binary data
70   has the following layout:
72   Offset        | Name          | Description
73   ====================================================================
74   0x00          | expected      | Number of expected RDS blocks
75   --------------------------------------------------------------------
76   0x02          | received      | Number of received RDS blocks
77   --------------------------------------------------------------------
78   0x04          | uncorrectable | Number of uncorrectable RDS blocks
79   --------------------------------------------------------------------
81 * /sys/kernel/debug/<device-name>/agc
82   This file contains information about parameters pertaining to
83   AGC(Automatic Gain Control)
85   The layout is:
86   Offset        | Name          | Description
87   ====================================================================
88   0x00          | mxhi          | 0 - FM Mixer PD high threshold is
89                 |               | not tripped
90                 |               | 1 - FM Mixer PD high threshold is
91                 |               | tripped
92   --------------------------------------------------------------------
93   0x01          | mxlo          | ditto for FM Mixer PD low
94   --------------------------------------------------------------------
95   0x02          | lnahi         | ditto for FM LNA PD high
96   --------------------------------------------------------------------
97   0x03          | lnalo         | ditto for FM LNA PD low
98   --------------------------------------------------------------------
99   0x04          | fmagc1        | FMAGC1 attenuator resistance
100                 |               | (see datasheet for more detail)
101   --------------------------------------------------------------------
102   0x05          | fmagc2        | ditto for FMAGC2
103   --------------------------------------------------------------------
104   0x06          | pgagain       | PGA gain in dB
105   --------------------------------------------------------------------
106   0x07          | fmwblang      | FM/WB LNA Gain in dB
107   --------------------------------------------------------------------
109 * /sys/kernel/debug/<device-name>/rsq
110   This file contains information about parameters pertaining to
111   RSQ(Received Signal Quality)
113   The layout is:
114   Offset        | Name          | Description
115   ====================================================================
116   0x00          | multhint      | 0 - multipath value has not crossed
117                 |               | the Multipath high threshold
118                 |               | 1 - multipath value has crossed
119                 |               | the Multipath high threshold
120   --------------------------------------------------------------------
121   0x01          | multlint      | ditto for Multipath low threshold
122   --------------------------------------------------------------------
123   0x02          | snrhint       | 0 - received signal's SNR has not
124                 |               | crossed high threshold
125                 |               | 1 - received signal's SNR has
126                 |               | crossed high threshold
127   --------------------------------------------------------------------
128   0x03          | snrlint       | ditto for low threshold
129   --------------------------------------------------------------------
130   0x04          | rssihint      | ditto for RSSI high threshold
131   --------------------------------------------------------------------
132   0x05          | rssilint      | ditto for RSSI low threshold
133   --------------------------------------------------------------------
134   0x06          | bltf          | Flag indicating if seek command
135                 |               | reached/wrapped seek band limit
136   --------------------------------------------------------------------
137   0x07          | snr_ready     | Indicates that SNR metrics is ready
138   --------------------------------------------------------------------
139   0x08          | rssiready     | ditto for RSSI metrics
140   --------------------------------------------------------------------
141   0x09          | injside       | 0 - Low-side injection is being used
142                 |               | 1 - High-side injection is used
143   --------------------------------------------------------------------
144   0x10          | afcrl         | Flag indicating if AFC rails
145   --------------------------------------------------------------------
146   0x11          | valid         | Flag indicating if channel is valid
147   --------------------------------------------------------------------
148   0x12          | readfreq      | Current tuned frequency
149   --------------------------------------------------------------------
150   0x14          | freqoff       | Signed frequency offset in units of
151                 |               | 2ppm
152   --------------------------------------------------------------------
153   0x15          | rssi          | Signed value of RSSI in dBuV
154   --------------------------------------------------------------------
155   0x16          | snr           | Signed RF SNR in dB
156   --------------------------------------------------------------------
157   0x17          | issi          | Signed Image Strength Signal
158                 |               | indicator
159   --------------------------------------------------------------------
160   0x18          | lassi         | Signed Low side adjacent Channel
161                 |               | Strength indicator
162   --------------------------------------------------------------------
163   0x19          | hassi         | ditto fpr High side
164   --------------------------------------------------------------------
165   0x20          | mult          | Multipath indicator
166   --------------------------------------------------------------------
167   0x21          | dev           | Frequency deviation
168   --------------------------------------------------------------------
169   0x24          | assi          | Adjacent channel SSI
170   --------------------------------------------------------------------
171   0x25          | usn           | Ultrasonic noise indicator
172   --------------------------------------------------------------------
173   0x26          | pilotdev      | Pilot deviation in units of 100 Hz
174   --------------------------------------------------------------------
175   0x27          | rdsdev        | ditto for RDS
176   --------------------------------------------------------------------
177   0x28          | assidev       | ditto for ASSI
178   --------------------------------------------------------------------
179   0x29          | strongdev     | Frequency deviation
180   --------------------------------------------------------------------
181   0x30          | rdspi         | RDS PI code
182   --------------------------------------------------------------------
184 * /sys/kernel/debug/<device-name>/rsq_primary
185   This file contains information about parameters pertaining to
186   RSQ(Received Signal Quality) for primary tuner only. Layout is as
187   the one above.