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Documentation / video4linux / si476x.txt


Based on kernel version 4.7.2. Page generated on 2016-08-22 22:48 EST.

1	SI476x Driver Readme
2	------------------------------------------------
3		Copyright (C) 2013 Andrey Smirnov <andrew.smirnov@gmail.com>
4	
5	TODO 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	
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.
22	
23	The 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	| 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	  --------------------------------------------------------------------
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.
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