1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * apds9300.c - IIO driver for Avago APDS9300 ambient light sensor
4 *
5 * Copyright 2013 Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
6 */
7
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 #include <linux/pm.h>
11 #include <linux/i2c.h>
12 #include <linux/err.h>
13 #include <linux/mutex.h>
14 #include <linux/interrupt.h>
15 #include <linux/iio/iio.h>
16 #include <linux/iio/sysfs.h>
17 #include <linux/iio/events.h>
18
19 #define APDS9300_DRV_NAME "apds9300"
20 #define APDS9300_IRQ_NAME "apds9300_event"
21
22 /* Command register bits */
23 #define APDS9300_CMD BIT(7) /* Select command register. Must write as 1 */
24 #define APDS9300_WORD BIT(5) /* I2C write/read: if 1 word, if 0 byte */
25 #define APDS9300_CLEAR BIT(6) /* Interrupt clear. Clears pending interrupt */
26
27 /* Register set */
28 #define APDS9300_CONTROL 0x00 /* Control of basic functions */
29 #define APDS9300_THRESHLOWLOW 0x02 /* Low byte of low interrupt threshold */
30 #define APDS9300_THRESHHIGHLOW 0x04 /* Low byte of high interrupt threshold */
31 #define APDS9300_INTERRUPT 0x06 /* Interrupt control */
32 #define APDS9300_DATA0LOW 0x0c /* Low byte of ADC channel 0 */
33 #define APDS9300_DATA1LOW 0x0e /* Low byte of ADC channel 1 */
34
35 /* Power on/off value for APDS9300_CONTROL register */
36 #define APDS9300_POWER_ON 0x03
37 #define APDS9300_POWER_OFF 0x00
38
39 /* Interrupts */
40 #define APDS9300_INTR_ENABLE 0x10
41 /* Interrupt Persist Function: Any value outside of threshold range */
42 #define APDS9300_THRESH_INTR 0x01
43
44 #define APDS9300_THRESH_MAX 0xffff /* Max threshold value */
45
46 struct apds9300_data {
47 struct i2c_client *client;
48 struct mutex mutex;
49 int power_state;
50 int thresh_low;
51 int thresh_hi;
52 int intr_en;
53 };
54
55 /* Lux calculation */
56
57 /* Calculated values 1000 * (CH1/CH0)^1.4 for CH1/CH0 from 0 to 0.52 */
58 static const u16 apds9300_lux_ratio[] = {
59 0, 2, 4, 7, 11, 15, 19, 24, 29, 34, 40, 45, 51, 57, 64, 70, 77, 84, 91,
60 98, 105, 112, 120, 128, 136, 144, 152, 160, 168, 177, 185, 194, 203,
61 212, 221, 230, 239, 249, 258, 268, 277, 287, 297, 307, 317, 327, 337,
62 347, 358, 368, 379, 390, 400,
63 };
64
apds9300_calculate_lux(u16 ch0,u16 ch1)65 static unsigned long apds9300_calculate_lux(u16 ch0, u16 ch1)
66 {
67 unsigned long lux, tmp;
68
69 /* avoid division by zero */
70 if (ch0 == 0)
71 return 0;
72
73 tmp = DIV_ROUND_UP(ch1 * 100, ch0);
74 if (tmp <= 52) {
75 lux = 3150 * ch0 - (unsigned long)DIV_ROUND_UP_ULL(ch0
76 * apds9300_lux_ratio[tmp] * 5930ull, 1000);
77 } else if (tmp <= 65) {
78 lux = 2290 * ch0 - 2910 * ch1;
79 } else if (tmp <= 80) {
80 lux = 1570 * ch0 - 1800 * ch1;
81 } else if (tmp <= 130) {
82 lux = 338 * ch0 - 260 * ch1;
83 } else {
84 lux = 0;
85 }
86
87 return lux / 100000;
88 }
89
apds9300_get_adc_val(struct apds9300_data * data,int adc_number)90 static int apds9300_get_adc_val(struct apds9300_data *data, int adc_number)
91 {
92 int ret;
93 u8 flags = APDS9300_CMD | APDS9300_WORD;
94
95 if (!data->power_state)
96 return -EBUSY;
97
98 /* Select ADC0 or ADC1 data register */
99 flags |= adc_number ? APDS9300_DATA1LOW : APDS9300_DATA0LOW;
100
101 ret = i2c_smbus_read_word_data(data->client, flags);
102 if (ret < 0)
103 dev_err(&data->client->dev,
104 "failed to read ADC%d value\n", adc_number);
105
106 return ret;
107 }
108
apds9300_set_thresh_low(struct apds9300_data * data,int value)109 static int apds9300_set_thresh_low(struct apds9300_data *data, int value)
110 {
111 int ret;
112
113 if (!data->power_state)
114 return -EBUSY;
115
116 if (value > APDS9300_THRESH_MAX)
117 return -EINVAL;
118
119 ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHLOWLOW
120 | APDS9300_CMD | APDS9300_WORD, value);
121 if (ret) {
122 dev_err(&data->client->dev, "failed to set thresh_low\n");
123 return ret;
124 }
125 data->thresh_low = value;
126
127 return 0;
128 }
129
apds9300_set_thresh_hi(struct apds9300_data * data,int value)130 static int apds9300_set_thresh_hi(struct apds9300_data *data, int value)
131 {
132 int ret;
133
134 if (!data->power_state)
135 return -EBUSY;
136
137 if (value > APDS9300_THRESH_MAX)
138 return -EINVAL;
139
140 ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHHIGHLOW
141 | APDS9300_CMD | APDS9300_WORD, value);
142 if (ret) {
143 dev_err(&data->client->dev, "failed to set thresh_hi\n");
144 return ret;
145 }
146 data->thresh_hi = value;
147
148 return 0;
149 }
150
apds9300_set_intr_state(struct apds9300_data * data,int state)151 static int apds9300_set_intr_state(struct apds9300_data *data, int state)
152 {
153 int ret;
154 u8 cmd;
155
156 if (!data->power_state)
157 return -EBUSY;
158
159 cmd = state ? APDS9300_INTR_ENABLE | APDS9300_THRESH_INTR : 0x00;
160 ret = i2c_smbus_write_byte_data(data->client,
161 APDS9300_INTERRUPT | APDS9300_CMD, cmd);
162 if (ret) {
163 dev_err(&data->client->dev,
164 "failed to set interrupt state %d\n", state);
165 return ret;
166 }
167 data->intr_en = state;
168
169 return 0;
170 }
171
apds9300_set_power_state(struct apds9300_data * data,int state)172 static int apds9300_set_power_state(struct apds9300_data *data, int state)
173 {
174 int ret;
175 u8 cmd;
176
177 cmd = state ? APDS9300_POWER_ON : APDS9300_POWER_OFF;
178 ret = i2c_smbus_write_byte_data(data->client,
179 APDS9300_CONTROL | APDS9300_CMD, cmd);
180 if (ret) {
181 dev_err(&data->client->dev,
182 "failed to set power state %d\n", state);
183 return ret;
184 }
185 data->power_state = state;
186
187 return 0;
188 }
189
apds9300_clear_intr(struct apds9300_data * data)190 static void apds9300_clear_intr(struct apds9300_data *data)
191 {
192 int ret;
193
194 ret = i2c_smbus_write_byte(data->client, APDS9300_CLEAR | APDS9300_CMD);
195 if (ret < 0)
196 dev_err(&data->client->dev, "failed to clear interrupt\n");
197 }
198
apds9300_chip_init(struct apds9300_data * data)199 static int apds9300_chip_init(struct apds9300_data *data)
200 {
201 int ret;
202
203 /* Need to set power off to ensure that the chip is off */
204 ret = apds9300_set_power_state(data, 0);
205 if (ret < 0)
206 goto err;
207 /*
208 * Probe the chip. To do so we try to power up the device and then to
209 * read back the 0x03 code
210 */
211 ret = apds9300_set_power_state(data, 1);
212 if (ret < 0)
213 goto err;
214 ret = i2c_smbus_read_byte_data(data->client,
215 APDS9300_CONTROL | APDS9300_CMD);
216 if (ret != APDS9300_POWER_ON) {
217 ret = -ENODEV;
218 goto err;
219 }
220 /*
221 * Disable interrupt to ensure thai it is doesn't enable
222 * i.e. after device soft reset
223 */
224 ret = apds9300_set_intr_state(data, 0);
225 if (ret < 0)
226 goto err;
227
228 return 0;
229
230 err:
231 dev_err(&data->client->dev, "failed to init the chip\n");
232 return ret;
233 }
234
apds9300_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)235 static int apds9300_read_raw(struct iio_dev *indio_dev,
236 struct iio_chan_spec const *chan, int *val, int *val2,
237 long mask)
238 {
239 int ch0, ch1, ret = -EINVAL;
240 struct apds9300_data *data = iio_priv(indio_dev);
241
242 mutex_lock(&data->mutex);
243 switch (chan->type) {
244 case IIO_LIGHT:
245 ch0 = apds9300_get_adc_val(data, 0);
246 if (ch0 < 0) {
247 ret = ch0;
248 break;
249 }
250 ch1 = apds9300_get_adc_val(data, 1);
251 if (ch1 < 0) {
252 ret = ch1;
253 break;
254 }
255 *val = apds9300_calculate_lux(ch0, ch1);
256 ret = IIO_VAL_INT;
257 break;
258 case IIO_INTENSITY:
259 ret = apds9300_get_adc_val(data, chan->channel);
260 if (ret < 0)
261 break;
262 *val = ret;
263 ret = IIO_VAL_INT;
264 break;
265 default:
266 break;
267 }
268 mutex_unlock(&data->mutex);
269
270 return ret;
271 }
272
apds9300_read_thresh(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int * val,int * val2)273 static int apds9300_read_thresh(struct iio_dev *indio_dev,
274 const struct iio_chan_spec *chan, enum iio_event_type type,
275 enum iio_event_direction dir, enum iio_event_info info,
276 int *val, int *val2)
277 {
278 struct apds9300_data *data = iio_priv(indio_dev);
279
280 switch (dir) {
281 case IIO_EV_DIR_RISING:
282 *val = data->thresh_hi;
283 break;
284 case IIO_EV_DIR_FALLING:
285 *val = data->thresh_low;
286 break;
287 default:
288 return -EINVAL;
289 }
290
291 return IIO_VAL_INT;
292 }
293
apds9300_write_thresh(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int val,int val2)294 static int apds9300_write_thresh(struct iio_dev *indio_dev,
295 const struct iio_chan_spec *chan, enum iio_event_type type,
296 enum iio_event_direction dir, enum iio_event_info info, int val,
297 int val2)
298 {
299 struct apds9300_data *data = iio_priv(indio_dev);
300 int ret;
301
302 mutex_lock(&data->mutex);
303 if (dir == IIO_EV_DIR_RISING)
304 ret = apds9300_set_thresh_hi(data, val);
305 else
306 ret = apds9300_set_thresh_low(data, val);
307 mutex_unlock(&data->mutex);
308
309 return ret;
310 }
311
apds9300_read_interrupt_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir)312 static int apds9300_read_interrupt_config(struct iio_dev *indio_dev,
313 const struct iio_chan_spec *chan,
314 enum iio_event_type type,
315 enum iio_event_direction dir)
316 {
317 struct apds9300_data *data = iio_priv(indio_dev);
318
319 return data->intr_en;
320 }
321
apds9300_write_interrupt_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,int state)322 static int apds9300_write_interrupt_config(struct iio_dev *indio_dev,
323 const struct iio_chan_spec *chan, enum iio_event_type type,
324 enum iio_event_direction dir, int state)
325 {
326 struct apds9300_data *data = iio_priv(indio_dev);
327 int ret;
328
329 mutex_lock(&data->mutex);
330 ret = apds9300_set_intr_state(data, state);
331 mutex_unlock(&data->mutex);
332
333 return ret;
334 }
335
336 static const struct iio_info apds9300_info_no_irq = {
337 .read_raw = apds9300_read_raw,
338 };
339
340 static const struct iio_info apds9300_info = {
341 .read_raw = apds9300_read_raw,
342 .read_event_value = apds9300_read_thresh,
343 .write_event_value = apds9300_write_thresh,
344 .read_event_config = apds9300_read_interrupt_config,
345 .write_event_config = apds9300_write_interrupt_config,
346 };
347
348 static const struct iio_event_spec apds9300_event_spec[] = {
349 {
350 .type = IIO_EV_TYPE_THRESH,
351 .dir = IIO_EV_DIR_RISING,
352 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
353 BIT(IIO_EV_INFO_ENABLE),
354 }, {
355 .type = IIO_EV_TYPE_THRESH,
356 .dir = IIO_EV_DIR_FALLING,
357 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
358 BIT(IIO_EV_INFO_ENABLE),
359 },
360 };
361
362 static const struct iio_chan_spec apds9300_channels[] = {
363 {
364 .type = IIO_LIGHT,
365 .channel = 0,
366 .indexed = true,
367 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
368 }, {
369 .type = IIO_INTENSITY,
370 .channel = 0,
371 .channel2 = IIO_MOD_LIGHT_BOTH,
372 .indexed = true,
373 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
374 .event_spec = apds9300_event_spec,
375 .num_event_specs = ARRAY_SIZE(apds9300_event_spec),
376 }, {
377 .type = IIO_INTENSITY,
378 .channel = 1,
379 .channel2 = IIO_MOD_LIGHT_IR,
380 .indexed = true,
381 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
382 },
383 };
384
apds9300_interrupt_handler(int irq,void * private)385 static irqreturn_t apds9300_interrupt_handler(int irq, void *private)
386 {
387 struct iio_dev *dev_info = private;
388 struct apds9300_data *data = iio_priv(dev_info);
389
390 iio_push_event(dev_info,
391 IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
392 IIO_EV_TYPE_THRESH,
393 IIO_EV_DIR_EITHER),
394 iio_get_time_ns(dev_info));
395
396 apds9300_clear_intr(data);
397
398 return IRQ_HANDLED;
399 }
400
apds9300_probe(struct i2c_client * client)401 static int apds9300_probe(struct i2c_client *client)
402 {
403 struct apds9300_data *data;
404 struct iio_dev *indio_dev;
405 int ret;
406
407 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
408 if (!indio_dev)
409 return -ENOMEM;
410
411 data = iio_priv(indio_dev);
412 i2c_set_clientdata(client, indio_dev);
413 data->client = client;
414
415 ret = apds9300_chip_init(data);
416 if (ret < 0)
417 goto err;
418
419 mutex_init(&data->mutex);
420
421 indio_dev->channels = apds9300_channels;
422 indio_dev->num_channels = ARRAY_SIZE(apds9300_channels);
423 indio_dev->name = APDS9300_DRV_NAME;
424 indio_dev->modes = INDIO_DIRECT_MODE;
425
426 if (client->irq)
427 indio_dev->info = &apds9300_info;
428 else
429 indio_dev->info = &apds9300_info_no_irq;
430
431 if (client->irq) {
432 ret = devm_request_threaded_irq(&client->dev, client->irq,
433 NULL, apds9300_interrupt_handler,
434 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
435 APDS9300_IRQ_NAME, indio_dev);
436 if (ret) {
437 dev_err(&client->dev, "irq request error %d\n", -ret);
438 goto err;
439 }
440 }
441
442 ret = iio_device_register(indio_dev);
443 if (ret < 0)
444 goto err;
445
446 return 0;
447
448 err:
449 /* Ensure that power off in case of error */
450 apds9300_set_power_state(data, 0);
451 return ret;
452 }
453
apds9300_remove(struct i2c_client * client)454 static void apds9300_remove(struct i2c_client *client)
455 {
456 struct iio_dev *indio_dev = i2c_get_clientdata(client);
457 struct apds9300_data *data = iio_priv(indio_dev);
458
459 iio_device_unregister(indio_dev);
460
461 /* Ensure that power off and interrupts are disabled */
462 apds9300_set_intr_state(data, 0);
463 apds9300_set_power_state(data, 0);
464 }
465
apds9300_suspend(struct device * dev)466 static int apds9300_suspend(struct device *dev)
467 {
468 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
469 struct apds9300_data *data = iio_priv(indio_dev);
470 int ret;
471
472 mutex_lock(&data->mutex);
473 ret = apds9300_set_power_state(data, 0);
474 mutex_unlock(&data->mutex);
475
476 return ret;
477 }
478
apds9300_resume(struct device * dev)479 static int apds9300_resume(struct device *dev)
480 {
481 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
482 struct apds9300_data *data = iio_priv(indio_dev);
483 int ret;
484
485 mutex_lock(&data->mutex);
486 ret = apds9300_set_power_state(data, 1);
487 mutex_unlock(&data->mutex);
488
489 return ret;
490 }
491
492 static DEFINE_SIMPLE_DEV_PM_OPS(apds9300_pm_ops, apds9300_suspend,
493 apds9300_resume);
494
495 static const struct i2c_device_id apds9300_id[] = {
496 { APDS9300_DRV_NAME, 0 },
497 { }
498 };
499
500 MODULE_DEVICE_TABLE(i2c, apds9300_id);
501
502 static struct i2c_driver apds9300_driver = {
503 .driver = {
504 .name = APDS9300_DRV_NAME,
505 .pm = pm_sleep_ptr(&apds9300_pm_ops),
506 },
507 .probe = apds9300_probe,
508 .remove = apds9300_remove,
509 .id_table = apds9300_id,
510 };
511
512 module_i2c_driver(apds9300_driver);
513
514 MODULE_AUTHOR("Kravchenko Oleksandr <o.v.kravchenko@globallogic.com>");
515 MODULE_AUTHOR("GlobalLogic inc.");
516 MODULE_DESCRIPTION("APDS9300 ambient light photo sensor driver");
517 MODULE_LICENSE("GPL");
518