1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
|
/*
* Driver for ISSI IS31FL32xx family of I2C LED controllers
*
* Copyright 2015 Allworx Corp.
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Datasheets:
* http://www.issi.com/US/product-analog-fxled-driver.shtml
* http://www.si-en.com/product.asp?parentid=890
*/
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
/* Used to indicate a device has no such register */
#define IS31FL32XX_REG_NONE 0xFF
/* Software Shutdown bit in Shutdown Register */
#define IS31FL32XX_SHUTDOWN_SSD_ENABLE 0
#define IS31FL32XX_SHUTDOWN_SSD_DISABLE BIT(0)
/* IS31FL3216 has a number of unique registers */
#define IS31FL3216_CONFIG_REG 0x00
#define IS31FL3216_LIGHTING_EFFECT_REG 0x03
#define IS31FL3216_CHANNEL_CONFIG_REG 0x04
/* Software Shutdown bit in 3216 Config Register */
#define IS31FL3216_CONFIG_SSD_ENABLE BIT(7)
#define IS31FL3216_CONFIG_SSD_DISABLE 0
struct is31fl32xx_priv;
struct is31fl32xx_led_data {
struct led_classdev cdev;
u8 channel; /* 1-based, max priv->cdef->channels */
struct is31fl32xx_priv *priv;
};
struct is31fl32xx_priv {
const struct is31fl32xx_chipdef *cdef;
struct i2c_client *client;
unsigned int num_leds;
struct is31fl32xx_led_data leds[0];
};
/**
* struct is31fl32xx_chipdef - chip-specific attributes
* @channels : Number of LED channels
* @shutdown_reg : address of Shutdown register (optional)
* @pwm_update_reg : address of PWM Update register
* @global_control_reg : address of Global Control register (optional)
* @reset_reg : address of Reset register (optional)
* @pwm_register_base : address of first PWM register
* @pwm_registers_reversed: : true if PWM registers count down instead of up
* @led_control_register_base : address of first LED control register (optional)
* @enable_bits_per_led_control_register: number of LEDs enable bits in each
* @reset_func: : pointer to reset function
*
* For all optional register addresses, the sentinel value %IS31FL32XX_REG_NONE
* indicates that this chip has no such register.
*
* If non-NULL, @reset_func will be called during probing to set all
* necessary registers to a known initialization state. This is needed
* for chips that do not have a @reset_reg.
*
* @enable_bits_per_led_control_register must be >=1 if
* @led_control_register_base != %IS31FL32XX_REG_NONE.
*/
struct is31fl32xx_chipdef {
u8 channels;
u8 shutdown_reg;
u8 pwm_update_reg;
u8 global_control_reg;
u8 reset_reg;
u8 pwm_register_base;
bool pwm_registers_reversed;
u8 led_control_register_base;
u8 enable_bits_per_led_control_register;
int (*reset_func)(struct is31fl32xx_priv *priv);
int (*sw_shutdown_func)(struct is31fl32xx_priv *priv, bool enable);
};
static const struct is31fl32xx_chipdef is31fl3236_cdef = {
.channels = 36,
.shutdown_reg = 0x00,
.pwm_update_reg = 0x25,
.global_control_reg = 0x4a,
.reset_reg = 0x4f,
.pwm_register_base = 0x01,
.led_control_register_base = 0x26,
.enable_bits_per_led_control_register = 1,
};
static const struct is31fl32xx_chipdef is31fl3235_cdef = {
.channels = 28,
.shutdown_reg = 0x00,
.pwm_update_reg = 0x25,
.global_control_reg = 0x4a,
.reset_reg = 0x4f,
.pwm_register_base = 0x05,
.led_control_register_base = 0x2a,
.enable_bits_per_led_control_register = 1,
};
static const struct is31fl32xx_chipdef is31fl3218_cdef = {
.channels = 18,
.shutdown_reg = 0x00,
.pwm_update_reg = 0x16,
.global_control_reg = IS31FL32XX_REG_NONE,
.reset_reg = 0x17,
.pwm_register_base = 0x01,
.led_control_register_base = 0x13,
.enable_bits_per_led_control_register = 6,
};
static int is31fl3216_reset(struct is31fl32xx_priv *priv);
static int is31fl3216_software_shutdown(struct is31fl32xx_priv *priv,
bool enable);
static const struct is31fl32xx_chipdef is31fl3216_cdef = {
.channels = 16,
.shutdown_reg = IS31FL32XX_REG_NONE,
.pwm_update_reg = 0xB0,
.global_control_reg = IS31FL32XX_REG_NONE,
.reset_reg = IS31FL32XX_REG_NONE,
.pwm_register_base = 0x10,
.pwm_registers_reversed = true,
.led_control_register_base = 0x01,
.enable_bits_per_led_control_register = 8,
.reset_func = is31fl3216_reset,
.sw_shutdown_func = is31fl3216_software_shutdown,
};
static int is31fl32xx_write(struct is31fl32xx_priv *priv, u8 reg, u8 val)
{
int ret;
dev_dbg(&priv->client->dev, "writing register 0x%02X=0x%02X", reg, val);
ret = i2c_smbus_write_byte_data(priv->client, reg, val);
if (ret) {
dev_err(&priv->client->dev,
"register write to 0x%02X failed (error %d)",
reg, ret);
}
return ret;
}
/*
* Custom reset function for IS31FL3216 because it does not have a RESET
* register the way that the other IS31FL32xx chips do. We don't bother
* writing the GPIO and animation registers, because the registers we
* do write ensure those will have no effect.
*/
static int is31fl3216_reset(struct is31fl32xx_priv *priv)
{
unsigned int i;
int ret;
ret = is31fl32xx_write(priv, IS31FL3216_CONFIG_REG,
IS31FL3216_CONFIG_SSD_ENABLE);
if (ret)
return ret;
for (i = 0; i < priv->cdef->channels; i++) {
ret = is31fl32xx_write(priv, priv->cdef->pwm_register_base+i,
0x00);
if (ret)
return ret;
}
ret = is31fl32xx_write(priv, priv->cdef->pwm_update_reg, 0);
if (ret)
return ret;
ret = is31fl32xx_write(priv, IS31FL3216_LIGHTING_EFFECT_REG, 0x00);
if (ret)
return ret;
ret = is31fl32xx_write(priv, IS31FL3216_CHANNEL_CONFIG_REG, 0x00);
if (ret)
return ret;
return 0;
}
/*
* Custom Software-Shutdown function for IS31FL3216 because it does not have
* a SHUTDOWN register the way that the other IS31FL32xx chips do.
* We don't bother doing a read/modify/write on the CONFIG register because
* we only ever use a value of '0' for the other fields in that register.
*/
static int is31fl3216_software_shutdown(struct is31fl32xx_priv *priv,
bool enable)
{
u8 value = enable ? IS31FL3216_CONFIG_SSD_ENABLE :
IS31FL3216_CONFIG_SSD_DISABLE;
return is31fl32xx_write(priv, IS31FL3216_CONFIG_REG, value);
}
/*
* NOTE: A mutex is not needed in this function because:
* - All referenced data is read-only after probe()
* - The I2C core has a mutex on to protect the bus
* - There are no read/modify/write operations
* - Intervening operations between the write of the PWM register
* and the Update register are harmless.
*
* Example:
* PWM_REG_1 write 16
* UPDATE_REG write 0
* PWM_REG_2 write 128
* UPDATE_REG write 0
* vs:
* PWM_REG_1 write 16
* PWM_REG_2 write 128
* UPDATE_REG write 0
* UPDATE_REG write 0
* are equivalent. Poking the Update register merely applies all PWM
* register writes up to that point.
*/
static int is31fl32xx_brightness_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
const struct is31fl32xx_led_data *led_data =
container_of(led_cdev, struct is31fl32xx_led_data, cdev);
const struct is31fl32xx_chipdef *cdef = led_data->priv->cdef;
u8 pwm_register_offset;
int ret;
dev_dbg(led_cdev->dev, "%s: %d\n", __func__, brightness);
/* NOTE: led_data->channel is 1-based */
if (cdef->pwm_registers_reversed)
pwm_register_offset = cdef->channels - led_data->channel;
else
pwm_register_offset = led_data->channel - 1;
ret = is31fl32xx_write(led_data->priv,
cdef->pwm_register_base + pwm_register_offset,
brightness);
if (ret)
return ret;
return is31fl32xx_write(led_data->priv, cdef->pwm_update_reg, 0);
}
static int is31fl32xx_reset_regs(struct is31fl32xx_priv *priv)
{
const struct is31fl32xx_chipdef *cdef = priv->cdef;
int ret;
if (cdef->reset_reg != IS31FL32XX_REG_NONE) {
ret = is31fl32xx_write(priv, cdef->reset_reg, 0);
if (ret)
return ret;
}
if (cdef->reset_func)
return cdef->reset_func(priv);
return 0;
}
static int is31fl32xx_software_shutdown(struct is31fl32xx_priv *priv,
bool enable)
{
const struct is31fl32xx_chipdef *cdef = priv->cdef;
int ret;
if (cdef->shutdown_reg != IS31FL32XX_REG_NONE) {
u8 value = enable ? IS31FL32XX_SHUTDOWN_SSD_ENABLE :
IS31FL32XX_SHUTDOWN_SSD_DISABLE;
ret = is31fl32xx_write(priv, cd
|