1 ========================
2 Kernel driver for lm3556
3 ========================
4
5 * Texas Instrument:
6 1.5 A Synchronous Boost LED Flash Driver w/
7 * Datasheet: http://www.national.com/ds/LM/LM3
8
9 Authors:
10 - Daniel Jeong
11
12 Contact:Daniel Jeong(daniel.jeong-at-t
13
14 Description
15 -----------
16 There are 3 functions in LM3556, Flash, Torch
17
18 Flash Mode
19 ^^^^^^^^^^
20
21 In Flash Mode, the LED current source(LED) pro
22 from 93.75 mA to 1500 mA.The Flash currents ar
23 CONTROL REGISTER(0x09).Flash mode is activated
24 or by pulling the STROBE pin HIGH.
25
26 LM3556 Flash can be controlled through /sys/cl
27
28 * if STROBE pin is enabled, below example cont
29 ON / OFF will be controlled by STROBE pin.
30
31 Flash Example:
32
33 OFF::
34
35 #echo 0 > /sys/class/leds/flash/bright
36
37 93.75 mA::
38
39 #echo 1 > /sys/class/leds/flash/bright
40
41 ...
42
43 1500 mA::
44
45 #echo 16 > /sys/class/leds/flash/brigh
46
47 Torch Mode
48 ^^^^^^^^^^
49
50 In Torch Mode, the current source(LED) is prog
51 REGISTER(0x09).Torch Mode is activated by the
52 hardware TORCH input.
53
54 LM3556 torch can be controlled through /sys/cl
55 * if TORCH pin is enabled, below example contr
56 and ON / OFF will be controlled by TORCH pin.
57
58 Torch Example:
59
60 OFF::
61
62 #echo 0 > /sys/class/leds/torch/bright
63
64 46.88 mA::
65
66 #echo 1 > /sys/class/leds/torch/bright
67
68 ...
69
70 375 mA::
71
72 #echo 8 > /sys/class/leds/torch/bright
73
74 Indicator Mode
75 ^^^^^^^^^^^^^^
76
77 Indicator pattern can be set through /sys/clas
78 and 4 patterns are pre-defined in indicator_pa
79
80 According to N-lank, Pulse time and N Period v
81 be generated.If you want new patterns for your
82 indicator_pattern array with your own values a
83
84 Please refer datasheet for more detail about N
85
86 Indicator pattern example:
87
88 pattern 0::
89
90 #echo 0 > /sys/class/leds/indicator/pa
91
92 ...
93
94 pattern 3::
95
96 #echo 3 > /sys/class/leds/indicator/pa
97
98 Indicator brightness can be controlled through
99 sys/class/leds/indicator/brightness file.
100
101 Example:
102
103 OFF::
104
105 #echo 0 > /sys/class/leds/indicator/br
106
107 5.86 mA::
108
109 #echo 1 > /sys/class/leds/indicator/br
110
111 ...
112
113 46.875mA::
114
115 #echo 8 > /sys/class/leds/indicator/br
116
117 Notes
118 -----
119 Driver expects it is registered using the i2c_
120 To register the chip at address 0x63 on specif
121 according to include/linux/platform_data/leds-
122
123 Example::
124
125 static struct i2c_board_info board_i2c
126 {
127 I2C_BOARD_INFO(LM3556
128 .platform_data = &lm3
129 },
130 };
131
132 and register it in the platform init function
133
134 Example::
135
136 board_register_i2c_bus(4, 400,
137 board_i2c_ch4,
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