1 ==============================================
2 LP5521/LP5523/LP55231/LP5562/LP8501 Common Dri
3 ==============================================
4
5 Authors: Milo(Woogyom) Kim <milo.kim@ti.com>
6
7 Description
8 -----------
9 LP5521, LP5523/55231, LP5562 and LP8501 have c
10
11 Register access via the I2C
12 Device initialization/deinitialization
13 Create LED class devices for multiple output
14 Device attributes for user-space interface
15 Program memory for running LED patterns
16
17 The LP55xx common driver provides these featur
18
19 lp55xx_init_device() / lp55xx_deinit_device(
20 lp55xx_register_leds() / lp55xx_unregister_l
21 lp55xx_regsister_sysfs() / lp55xx_unregister
22
23 ( Driver Structure Data )
24
25 In lp55xx common driver, two different data st
26
27 * lp55xx_led
28 control multi output LED channels such as
29 * lp55xx_chip
30 general chip control such like the I2C and
31
32 For example, LP5521 has maximum 3 LED channels
33 LP5523/55231 has 9 output channels::
34
35 lp55xx_chip for LP5521 ... lp55xx_led #1
36 lp55xx_led #2
37 lp55xx_led #3
38
39 lp55xx_chip for LP5523 ... lp55xx_led #1
40 lp55xx_led #2
41 .
42 .
43 lp55xx_led #9
44
45 ( Chip Dependent Code )
46
47 To support device specific configurations, spe
48 'lpxx_device_config' is used.
49
50 - Maximum number of channels
51 - Reset command, chip enable command
52 - Chip specific initialization
53 - Brightness control register access
54 - Setting LED output current
55 - Program memory address access for running
56 - Additional device specific attributes
57
58 ( Firmware Interface )
59
60 LP55xx family devices have the internal progra
61 various LED patterns.
62
63 This pattern data is saved as a file in the us
64 hex byte string is written into the memory thr
65
66 LP55xx common driver supports the firmware int
67
68 LP55xx chips have three program engines.
69
70 To load and run the pattern, the programming s
71
72 (1) Select an engine number (1/2/3)
73 (2) Mode change to load
74 (3) Write pattern data into selected area
75 (4) Mode change to run
76
77 The LP55xx common driver provides simple inter
78
79 select_engine:
80 Select which engine is used for runnin
81 run_engine:
82 Start program which is loaded via the
83 firmware:
84 Load program data
85
86 In case of LP5523, one more command is require
87 It is used for selecting LED output(s) at each
88 In more details, please refer to 'leds-lp5523.
89
90 For example, run blinking pattern in engine #1
91
92 echo 1 > /sys/bus/i2c/devices/xxxx/sel
93 echo 1 > /sys/class/firmware/lp5521/lo
94 echo "4000600040FF6000" > /sys/class/f
95 echo 0 > /sys/class/firmware/lp5521/lo
96 echo 1 > /sys/bus/i2c/devices/xxxx/run
97
98 For example, run blinking pattern in engine #3
99
100 Two LEDs are configured as pattern output chan
101
102 echo 3 > /sys/bus/i2c/devices/xxxx/sel
103 echo 1 > /sys/class/firmware/lp55231/l
104 echo "9d0740ff7e0040007e00a0010000" >
105 echo 0 > /sys/class/firmware/lp55231/l
106 echo "000001100" > /sys/bus/i2c/device
107 echo 1 > /sys/bus/i2c/devices/xxxx/run
108
109 To start blinking patterns in engine #2 and #3
110
111 for idx in 2 3
112 do
113 echo $idx > /sys/class/leds/red/device
114 sleep 0.1
115 echo 1 > /sys/class/firmware/lp5521/lo
116 echo "4000600040FF6000" > /sys/class/f
117 echo 0 > /sys/class/firmware/lp5521/lo
118 done
119 echo 1 > /sys/class/leds/red/device/ru
120
121 Here is another example for LP5523.
122
123 Full LED strings are selected by 'engine2_leds
124
125 echo 2 > /sys/bus/i2c/devices/xxxx/sel
126 echo 1 > /sys/class/firmware/lp5523/lo
127 echo "9d80400004ff05ff437f0000" > /sys
128 echo 0 > /sys/class/firmware/lp5523/lo
129 echo "111111111" > /sys/bus/i2c/device
130 echo 1 > /sys/bus/i2c/devices/xxxx/run
131
132 As soon as 'loading' is set to 0, registered c
133 Inside the callback, the selected engine is lo
134 To run programmed pattern, 'run_engine' attrib
135
136 The pattern sequence of LP8501 is similar to L
137
138 However pattern data is specific.
139
140 Ex 1) Engine 1 is used::
141
142 echo 1 > /sys/bus/i2c/devices/xxxx/sel
143 echo 1 > /sys/class/firmware/lp8501/lo
144 echo "9d0140ff7e0040007e00a001c000" >
145 echo 0 > /sys/class/firmware/lp8501/lo
146 echo 1 > /sys/bus/i2c/devices/xxxx/run
147
148 Ex 2) Engine 2 and 3 are used at the same time
149
150 echo 2 > /sys/bus/i2c/devices/xxxx/sel
151 sleep 1
152 echo 1 > /sys/class/firmware/lp8501/lo
153 echo "9d0140ff7e0040007e00a001c000" >
154 echo 0 > /sys/class/firmware/lp8501/lo
155 sleep 1
156 echo 3 > /sys/bus/i2c/devices/xxxx/sel
157 sleep 1
158 echo 1 > /sys/class/firmware/lp8501/lo
159 echo "9d0340ff7e0040007e00a001c000" >
160 echo 0 > /sys/class/firmware/lp8501/lo
161 sleep 1
162 echo 1 > /sys/class/leds/d1/device/run
163
164 ( 'run_engine' and 'firmware_cb' )
165
166 The sequence of running the program data is co
167
168 But each device has own specific register addr
169
170 To support this, 'run_engine' and 'firmware_cb
171
172 run_engine:
173 Control the selected engine
174 firmware_cb:
175 The callback function after loading th
176
177 Chip specific commands for loading and
178
179 ( Predefined pattern data )
180
181 Without the firmware interface, LP55xx driver
182 loading a LED pattern. That is 'predefined' pa
183
184 A predefined pattern is defined in the platfor
185 via the sysfs if needed.
186
187 To use the predefined pattern concept, 'patter
188 configured.
189
190 Example of predefined pattern data::
191
192 /* mode_1: blinking data */
193 static const u8 mode_1[] = {
194 0x40, 0x00, 0x60, 0x00, 0x40,
195 };
196
197 /* mode_2: always on */
198 static const u8 mode_2[] = { 0x40, 0xFF, };
199
200 struct lp55xx_predef_pattern board_led_patte
201 {
202 .r = mode_1,
203 .size_r = ARRAY_SIZE(mode_1),
204 },
205 {
206 .b = mode_2,
207 .size_b = ARRAY_SIZE(mode_2),
208 },
209 }
210
211 struct lp55xx_platform_data lp5562_pdata = {
212 ...
213 .patterns = board_led_patterns,
214 .num_patterns = ARRAY_SIZE(board_led_
215 };
216
217 Then, mode_1 and mode_2 can be run via through
218
219 echo 1 > /sys/bus/i2c/devices/xxxx/led_patte
220 echo 2 > /sys/bus/i2c/devices/xxxx/led_patte
221
222 To stop running pattern::
223
224 echo 0 > /sys/bus/i2c/devices/xxxx/led_patte
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