aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/video4linux
diff options
context:
space:
mode:
authorAndrey Smirnov <andrew.smirnov@gmail.com>2013-04-18 19:46:08 -0400
committerMauro Carvalho Chehab <mchehab@redhat.com>2013-04-18 20:20:34 -0400
commitb879a9c2a755d4ddf9e685258de6435710fd2f03 (patch)
tree8d4bd6c9df347b7d92dfd2523cb2987e78868108 /Documentation/video4linux
parent6695be6863b75620ffa6d422965680ce785cb7c8 (diff)
[media] v4l2: Add a V4L2 driver for SI476X MFD
This commit adds a driver that exposes all the radio related functionality of the Si476x series of chips via the V4L2 subsystem. [mchehab@redhat.com: change it to depends on MFD_SI476X_CORE instead of selecting it; vidioc_s_register now uses const struct] Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/video4linux')
-rw-r--r--Documentation/video4linux/si476x.txt187
1 files changed, 187 insertions, 0 deletions
diff --git a/Documentation/video4linux/si476x.txt b/Documentation/video4linux/si476x.txt
new file mode 100644
index 000000000000..d1a08db2cbd9
--- /dev/null
+++ b/Documentation/video4linux/si476x.txt
@@ -0,0 +1,187 @@
1SI476x Driver Readme
2------------------------------------------------
3 Copyright (C) 2013 Andrey Smirnov <andrew.smirnov@gmail.com>
4
5TODO for the driver
6------------------------------
7
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.
14
15
16Parameters exposed over debugfs
17-------------------------------
18SI476x allow user to get multiple characteristics that can be very
19useful for EoL testing/RF performance estimation, parameters that have
20very little to do with V4L2 subsystem. Such parameters are exposed via
21debugfs and can be accessed via regular file I/O operations.
22
23The drivers exposes following files:
24
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:
29
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 --------------------------------------------------------------------
66
67
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:
71
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 --------------------------------------------------------------------
80
81* /sys/kernel/debug/<device-name>/agc
82 This file contains information about parameters pertaining to
83 AGC(Automatic Gain Control)
84
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 --------------------------------------------------------------------
108
109* /sys/kernel/debug/<device-name>/rsq
110 This file contains information about parameters pertaining to
111 RSQ(Received Signal Quality)
112
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 | Singed 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 | Adjascent 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 --------------------------------------------------------------------
183
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.
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-18 13:43:13 -0500