1 ========================
2 Kernel driver for lp5521
3 ========================
4
5 * National Semiconductor LP5521 led driver chi
6 * Datasheet: http://www.national.com/pf/LP/LP5
7
8 Authors: Mathias Nyman, Yuri Zaporozhets, Samu
9
10 Contact: Samu Onkalo (samu.p.onkalo-at-nokia.c
11
12 Description
13 -----------
14
15 LP5521 can drive up to 3 channels. Leds can be
16 the led class control interface. Channels have
17 lp5521:channelx, where x is 0 .. 2
18
19 All three channels can be also controlled usin
20 More details of the instructions can be found
21
22 LP5521 has the internal program memory for run
23 There are two ways to run LED patterns.
24
25 1) Legacy interface - enginex_mode and enginex
26 Control interface for the engines:
27
28 x is 1 .. 3
29
30 enginex_mode:
31 disabled, load, run
32 enginex_load:
33 store program (visible only in engine
34
35 Example (start to blink the channel 2 led)::
36
37 cd /sys/class/leds/lp5521:channel2/d
38 echo "load" > engine3_mode
39 echo "037f4d0003ff6000" > engine3_load
40 echo "run" > engine3_mode
41
42 To stop the engine::
43
44 echo "disabled" > engine3_mode
45
46 2) Firmware interface - LP55xx common interfac
47
48 For the details, please refer to 'firmware' se
49
50 sysfs contains a selftest entry.
51
52 The test communicates with the chip and checks
53 the clock mode is automatically set to the req
54
55 Each channel has its own led current settings.
56
57 - /sys/class/leds/lp5521:channel0/led_current
58 - /sys/class/leds/lp5521:channel0/max_current
59
60 Format: 10x mA i.e 10 means 1.0 mA
61
62 example platform data::
63
64 static struct lp55xx_led_config lp5521_led_c
65 {
66 .name = "red",
67 .chan_nr = 0,
68 .led_current = 50,
69 .max_current = 130,
70 }, {
71 .name = "green",
72 .chan_nr = 1,
73 .led_current = 0,
74 .max_current = 130,
75 }, {
76 .name = "blue",
77 .chan_nr = 2,
78 .led_current = 0,
79 .max_current = 130,
80 }
81 };
82
83 static int lp5521_setup(void)
84 {
85 /* setup HW resources */
86 }
87
88 static void lp5521_release(void)
89 {
90 /* Release HW resources */
91 }
92
93 static void lp5521_enable(bool state)
94 {
95 /* Control of chip enable signal */
96 }
97
98 static struct lp55xx_platform_data lp5521_pl
99 .led_config = lp5521_led_config,
100 .num_channels = ARRAY_SIZE(lp5521_
101 .clock_mode = LP55XX_CLOCK_EXT,
102 .setup_resources = lp5521_setup,
103 .release_resources = lp5521_release,
104 .enable = lp5521_enable,
105 };
106
107 Note:
108 chan_nr can have values between 0 and 2.
109 The name of each channel can be configurable
110 If the name field is not defined, the defaul
111 (XXXX : pdata->label or i2c client name, N :
112
113
114 If the current is set to 0 in the platform dat
115 disabled and it is not visible in the sysfs.
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