mm, page_alloc: set alloc_flags only once in slowpath
[linux/fpc-iii.git] / drivers / iio / light / stk3310.c
blob45cf8b0a43637863456240d6c6bfce9e42db9790
1 /**
2 * Sensortek STK3310/STK3311 Ambient Light and Proximity Sensor
4 * Copyright (c) 2015, Intel Corporation.
6 * This file is subject to the terms and conditions of version 2 of
7 * the GNU General Public License. See the file COPYING in the main
8 * directory of this archive for more details.
10 * IIO driver for STK3310/STK3311. 7-bit I2C address: 0x48.
13 #include <linux/acpi.h>
14 #include <linux/i2c.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/regmap.h>
19 #include <linux/iio/events.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
23 #define STK3310_REG_STATE 0x00
24 #define STK3310_REG_PSCTRL 0x01
25 #define STK3310_REG_ALSCTRL 0x02
26 #define STK3310_REG_INT 0x04
27 #define STK3310_REG_THDH_PS 0x06
28 #define STK3310_REG_THDL_PS 0x08
29 #define STK3310_REG_FLAG 0x10
30 #define STK3310_REG_PS_DATA_MSB 0x11
31 #define STK3310_REG_PS_DATA_LSB 0x12
32 #define STK3310_REG_ALS_DATA_MSB 0x13
33 #define STK3310_REG_ALS_DATA_LSB 0x14
34 #define STK3310_REG_ID 0x3E
35 #define STK3310_MAX_REG 0x80
37 #define STK3310_STATE_EN_PS BIT(0)
38 #define STK3310_STATE_EN_ALS BIT(1)
39 #define STK3310_STATE_STANDBY 0x00
41 #define STK3310_CHIP_ID_VAL 0x13
42 #define STK3311_CHIP_ID_VAL 0x1D
43 #define STK3310_PSINT_EN 0x01
44 #define STK3310_PS_MAX_VAL 0xFFFF
46 #define STK3310_DRIVER_NAME "stk3310"
47 #define STK3310_REGMAP_NAME "stk3310_regmap"
48 #define STK3310_EVENT "stk3310_event"
50 #define STK3310_SCALE_AVAILABLE "6.4 1.6 0.4 0.1"
52 #define STK3310_IT_AVAILABLE \
53 "0.000185 0.000370 0.000741 0.001480 0.002960 0.005920 0.011840 " \
54 "0.023680 0.047360 0.094720 0.189440 0.378880 0.757760 1.515520 " \
55 "3.031040 6.062080"
57 #define STK3310_REGFIELD(name) \
58 do { \
59 data->reg_##name = \
60 devm_regmap_field_alloc(&client->dev, regmap, \
61 stk3310_reg_field_##name); \
62 if (IS_ERR(data->reg_##name)) { \
63 dev_err(&client->dev, "reg field alloc failed.\n"); \
64 return PTR_ERR(data->reg_##name); \
65 } \
66 } while (0)
68 static const struct reg_field stk3310_reg_field_state =
69 REG_FIELD(STK3310_REG_STATE, 0, 2);
70 static const struct reg_field stk3310_reg_field_als_gain =
71 REG_FIELD(STK3310_REG_ALSCTRL, 4, 5);
72 static const struct reg_field stk3310_reg_field_ps_gain =
73 REG_FIELD(STK3310_REG_PSCTRL, 4, 5);
74 static const struct reg_field stk3310_reg_field_als_it =
75 REG_FIELD(STK3310_REG_ALSCTRL, 0, 3);
76 static const struct reg_field stk3310_reg_field_ps_it =
77 REG_FIELD(STK3310_REG_PSCTRL, 0, 3);
78 static const struct reg_field stk3310_reg_field_int_ps =
79 REG_FIELD(STK3310_REG_INT, 0, 2);
80 static const struct reg_field stk3310_reg_field_flag_psint =
81 REG_FIELD(STK3310_REG_FLAG, 4, 4);
82 static const struct reg_field stk3310_reg_field_flag_nf =
83 REG_FIELD(STK3310_REG_FLAG, 0, 0);
85 /* Estimate maximum proximity values with regard to measurement scale. */
86 static const int stk3310_ps_max[4] = {
87 STK3310_PS_MAX_VAL / 640,
88 STK3310_PS_MAX_VAL / 160,
89 STK3310_PS_MAX_VAL / 40,
90 STK3310_PS_MAX_VAL / 10
93 static const int stk3310_scale_table[][2] = {
94 {6, 400000}, {1, 600000}, {0, 400000}, {0, 100000}
97 /* Integration time in seconds, microseconds */
98 static const int stk3310_it_table[][2] = {
99 {0, 185}, {0, 370}, {0, 741}, {0, 1480},
100 {0, 2960}, {0, 5920}, {0, 11840}, {0, 23680},
101 {0, 47360}, {0, 94720}, {0, 189440}, {0, 378880},
102 {0, 757760}, {1, 515520}, {3, 31040}, {6, 62080},
105 struct stk3310_data {
106 struct i2c_client *client;
107 struct mutex lock;
108 bool als_enabled;
109 bool ps_enabled;
110 u64 timestamp;
111 struct regmap *regmap;
112 struct regmap_field *reg_state;
113 struct regmap_field *reg_als_gain;
114 struct regmap_field *reg_ps_gain;
115 struct regmap_field *reg_als_it;
116 struct regmap_field *reg_ps_it;
117 struct regmap_field *reg_int_ps;
118 struct regmap_field *reg_flag_psint;
119 struct regmap_field *reg_flag_nf;
122 static const struct iio_event_spec stk3310_events[] = {
123 /* Proximity event */
125 .type = IIO_EV_TYPE_THRESH,
126 .dir = IIO_EV_DIR_RISING,
127 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
128 BIT(IIO_EV_INFO_ENABLE),
130 /* Out-of-proximity event */
132 .type = IIO_EV_TYPE_THRESH,
133 .dir = IIO_EV_DIR_FALLING,
134 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
135 BIT(IIO_EV_INFO_ENABLE),
139 static const struct iio_chan_spec stk3310_channels[] = {
141 .type = IIO_LIGHT,
142 .info_mask_separate =
143 BIT(IIO_CHAN_INFO_RAW) |
144 BIT(IIO_CHAN_INFO_SCALE) |
145 BIT(IIO_CHAN_INFO_INT_TIME),
148 .type = IIO_PROXIMITY,
149 .info_mask_separate =
150 BIT(IIO_CHAN_INFO_RAW) |
151 BIT(IIO_CHAN_INFO_SCALE) |
152 BIT(IIO_CHAN_INFO_INT_TIME),
153 .event_spec = stk3310_events,
154 .num_event_specs = ARRAY_SIZE(stk3310_events),
158 static IIO_CONST_ATTR(in_illuminance_scale_available, STK3310_SCALE_AVAILABLE);
160 static IIO_CONST_ATTR(in_proximity_scale_available, STK3310_SCALE_AVAILABLE);
162 static IIO_CONST_ATTR(in_illuminance_integration_time_available,
163 STK3310_IT_AVAILABLE);
165 static IIO_CONST_ATTR(in_proximity_integration_time_available,
166 STK3310_IT_AVAILABLE);
168 static struct attribute *stk3310_attributes[] = {
169 &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
170 &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
171 &iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
172 &iio_const_attr_in_proximity_integration_time_available.dev_attr.attr,
173 NULL,
176 static const struct attribute_group stk3310_attribute_group = {
177 .attrs = stk3310_attributes
180 static int stk3310_get_index(const int table[][2], int table_size,
181 int val, int val2)
183 int i;
185 for (i = 0; i < table_size; i++) {
186 if (val == table[i][0] && val2 == table[i][1])
187 return i;
190 return -EINVAL;
193 static int stk3310_read_event(struct iio_dev *indio_dev,
194 const struct iio_chan_spec *chan,
195 enum iio_event_type type,
196 enum iio_event_direction dir,
197 enum iio_event_info info,
198 int *val, int *val2)
200 u8 reg;
201 __be16 buf;
202 int ret;
203 struct stk3310_data *data = iio_priv(indio_dev);
205 if (info != IIO_EV_INFO_VALUE)
206 return -EINVAL;
208 /* Only proximity interrupts are implemented at the moment. */
209 if (dir == IIO_EV_DIR_RISING)
210 reg = STK3310_REG_THDH_PS;
211 else if (dir == IIO_EV_DIR_FALLING)
212 reg = STK3310_REG_THDL_PS;
213 else
214 return -EINVAL;
216 mutex_lock(&data->lock);
217 ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
218 mutex_unlock(&data->lock);
219 if (ret < 0) {
220 dev_err(&data->client->dev, "register read failed\n");
221 return ret;
223 *val = be16_to_cpu(buf);
225 return IIO_VAL_INT;
228 static int stk3310_write_event(struct iio_dev *indio_dev,
229 const struct iio_chan_spec *chan,
230 enum iio_event_type type,
231 enum iio_event_direction dir,
232 enum iio_event_info info,
233 int val, int val2)
235 u8 reg;
236 __be16 buf;
237 int ret;
238 unsigned int index;
239 struct stk3310_data *data = iio_priv(indio_dev);
240 struct i2c_client *client = data->client;
242 ret = regmap_field_read(data->reg_ps_gain, &index);
243 if (ret < 0)
244 return ret;
246 if (val < 0 || val > stk3310_ps_max[index])
247 return -EINVAL;
249 if (dir == IIO_EV_DIR_RISING)
250 reg = STK3310_REG_THDH_PS;
251 else if (dir == IIO_EV_DIR_FALLING)
252 reg = STK3310_REG_THDL_PS;
253 else
254 return -EINVAL;
256 buf = cpu_to_be16(val);
257 ret = regmap_bulk_write(data->regmap, reg, &buf, 2);
258 if (ret < 0)
259 dev_err(&client->dev, "failed to set PS threshold!\n");
261 return ret;
264 static int stk3310_read_event_config(struct iio_dev *indio_dev,
265 const struct iio_chan_spec *chan,
266 enum iio_event_type type,
267 enum iio_event_direction dir)
269 unsigned int event_val;
270 int ret;
271 struct stk3310_data *data = iio_priv(indio_dev);
273 ret = regmap_field_read(data->reg_int_ps, &event_val);
274 if (ret < 0)
275 return ret;
277 return event_val;
280 static int stk3310_write_event_config(struct iio_dev *indio_dev,
281 const struct iio_chan_spec *chan,
282 enum iio_event_type type,
283 enum iio_event_direction dir,
284 int state)
286 int ret;
287 struct stk3310_data *data = iio_priv(indio_dev);
288 struct i2c_client *client = data->client;
290 if (state < 0 || state > 7)
291 return -EINVAL;
293 /* Set INT_PS value */
294 mutex_lock(&data->lock);
295 ret = regmap_field_write(data->reg_int_ps, state);
296 if (ret < 0)
297 dev_err(&client->dev, "failed to set interrupt mode\n");
298 mutex_unlock(&data->lock);
300 return ret;
303 static int stk3310_read_raw(struct iio_dev *indio_dev,
304 struct iio_chan_spec const *chan,
305 int *val, int *val2, long mask)
307 u8 reg;
308 __be16 buf;
309 int ret;
310 unsigned int index;
311 struct stk3310_data *data = iio_priv(indio_dev);
312 struct i2c_client *client = data->client;
314 if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
315 return -EINVAL;
317 switch (mask) {
318 case IIO_CHAN_INFO_RAW:
319 if (chan->type == IIO_LIGHT)
320 reg = STK3310_REG_ALS_DATA_MSB;
321 else
322 reg = STK3310_REG_PS_DATA_MSB;
324 mutex_lock(&data->lock);
325 ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
326 if (ret < 0) {
327 dev_err(&client->dev, "register read failed\n");
328 mutex_unlock(&data->lock);
329 return ret;
331 *val = be16_to_cpu(buf);
332 mutex_unlock(&data->lock);
333 return IIO_VAL_INT;
334 case IIO_CHAN_INFO_INT_TIME:
335 if (chan->type == IIO_LIGHT)
336 ret = regmap_field_read(data->reg_als_it, &index);
337 else
338 ret = regmap_field_read(data->reg_ps_it, &index);
339 if (ret < 0)
340 return ret;
342 *val = stk3310_it_table[index][0];
343 *val2 = stk3310_it_table[index][1];
344 return IIO_VAL_INT_PLUS_MICRO;
345 case IIO_CHAN_INFO_SCALE:
346 if (chan->type == IIO_LIGHT)
347 ret = regmap_field_read(data->reg_als_gain, &index);
348 else
349 ret = regmap_field_read(data->reg_ps_gain, &index);
350 if (ret < 0)
351 return ret;
353 *val = stk3310_scale_table[index][0];
354 *val2 = stk3310_scale_table[index][1];
355 return IIO_VAL_INT_PLUS_MICRO;
358 return -EINVAL;
361 static int stk3310_write_raw(struct iio_dev *indio_dev,
362 struct iio_chan_spec const *chan,
363 int val, int val2, long mask)
365 int ret;
366 int index;
367 struct stk3310_data *data = iio_priv(indio_dev);
369 if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
370 return -EINVAL;
372 switch (mask) {
373 case IIO_CHAN_INFO_INT_TIME:
374 index = stk3310_get_index(stk3310_it_table,
375 ARRAY_SIZE(stk3310_it_table),
376 val, val2);
377 if (index < 0)
378 return -EINVAL;
379 mutex_lock(&data->lock);
380 if (chan->type == IIO_LIGHT)
381 ret = regmap_field_write(data->reg_als_it, index);
382 else
383 ret = regmap_field_write(data->reg_ps_it, index);
384 if (ret < 0)
385 dev_err(&data->client->dev,
386 "sensor configuration failed\n");
387 mutex_unlock(&data->lock);
388 return ret;
390 case IIO_CHAN_INFO_SCALE:
391 index = stk3310_get_index(stk3310_scale_table,
392 ARRAY_SIZE(stk3310_scale_table),
393 val, val2);
394 if (index < 0)
395 return -EINVAL;
396 mutex_lock(&data->lock);
397 if (chan->type == IIO_LIGHT)
398 ret = regmap_field_write(data->reg_als_gain, index);
399 else
400 ret = regmap_field_write(data->reg_ps_gain, index);
401 if (ret < 0)
402 dev_err(&data->client->dev,
403 "sensor configuration failed\n");
404 mutex_unlock(&data->lock);
405 return ret;
408 return -EINVAL;
411 static const struct iio_info stk3310_info = {
412 .driver_module = THIS_MODULE,
413 .read_raw = stk3310_read_raw,
414 .write_raw = stk3310_write_raw,
415 .attrs = &stk3310_attribute_group,
416 .read_event_value = stk3310_read_event,
417 .write_event_value = stk3310_write_event,
418 .read_event_config = stk3310_read_event_config,
419 .write_event_config = stk3310_write_event_config,
422 static int stk3310_set_state(struct stk3310_data *data, u8 state)
424 int ret;
425 struct i2c_client *client = data->client;
427 /* 3-bit state; 0b100 is not supported. */
428 if (state > 7 || state == 4)
429 return -EINVAL;
431 mutex_lock(&data->lock);
432 ret = regmap_field_write(data->reg_state, state);
433 if (ret < 0) {
434 dev_err(&client->dev, "failed to change sensor state\n");
435 } else if (state != STK3310_STATE_STANDBY) {
436 /* Don't reset the 'enabled' flags if we're going in standby */
437 data->ps_enabled = !!(state & STK3310_STATE_EN_PS);
438 data->als_enabled = !!(state & STK3310_STATE_EN_ALS);
440 mutex_unlock(&data->lock);
442 return ret;
445 static int stk3310_init(struct iio_dev *indio_dev)
447 int ret;
448 int chipid;
449 u8 state;
450 struct stk3310_data *data = iio_priv(indio_dev);
451 struct i2c_client *client = data->client;
453 ret = regmap_read(data->regmap, STK3310_REG_ID, &chipid);
454 if (ret < 0)
455 return ret;
457 if (chipid != STK3310_CHIP_ID_VAL &&
458 chipid != STK3311_CHIP_ID_VAL) {
459 dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
460 return -ENODEV;
463 state = STK3310_STATE_EN_ALS | STK3310_STATE_EN_PS;
464 ret = stk3310_set_state(data, state);
465 if (ret < 0) {
466 dev_err(&client->dev, "failed to enable sensor");
467 return ret;
470 /* Enable PS interrupts */
471 ret = regmap_field_write(data->reg_int_ps, STK3310_PSINT_EN);
472 if (ret < 0)
473 dev_err(&client->dev, "failed to enable interrupts!\n");
475 return ret;
478 static bool stk3310_is_volatile_reg(struct device *dev, unsigned int reg)
480 switch (reg) {
481 case STK3310_REG_ALS_DATA_MSB:
482 case STK3310_REG_ALS_DATA_LSB:
483 case STK3310_REG_PS_DATA_LSB:
484 case STK3310_REG_PS_DATA_MSB:
485 case STK3310_REG_FLAG:
486 return true;
487 default:
488 return false;
492 static struct regmap_config stk3310_regmap_config = {
493 .name = STK3310_REGMAP_NAME,
494 .reg_bits = 8,
495 .val_bits = 8,
496 .max_register = STK3310_MAX_REG,
497 .cache_type = REGCACHE_RBTREE,
498 .volatile_reg = stk3310_is_volatile_reg,
501 static int stk3310_regmap_init(struct stk3310_data *data)
503 struct regmap *regmap;
504 struct i2c_client *client;
506 client = data->client;
507 regmap = devm_regmap_init_i2c(client, &stk3310_regmap_config);
508 if (IS_ERR(regmap)) {
509 dev_err(&client->dev, "regmap initialization failed.\n");
510 return PTR_ERR(regmap);
512 data->regmap = regmap;
514 STK3310_REGFIELD(state);
515 STK3310_REGFIELD(als_gain);
516 STK3310_REGFIELD(ps_gain);
517 STK3310_REGFIELD(als_it);
518 STK3310_REGFIELD(ps_it);
519 STK3310_REGFIELD(int_ps);
520 STK3310_REGFIELD(flag_psint);
521 STK3310_REGFIELD(flag_nf);
523 return 0;
526 static irqreturn_t stk3310_irq_handler(int irq, void *private)
528 struct iio_dev *indio_dev = private;
529 struct stk3310_data *data = iio_priv(indio_dev);
531 data->timestamp = iio_get_time_ns(indio_dev);
533 return IRQ_WAKE_THREAD;
536 static irqreturn_t stk3310_irq_event_handler(int irq, void *private)
538 int ret;
539 unsigned int dir;
540 u64 event;
542 struct iio_dev *indio_dev = private;
543 struct stk3310_data *data = iio_priv(indio_dev);
545 /* Read FLAG_NF to figure out what threshold has been met. */
546 mutex_lock(&data->lock);
547 ret = regmap_field_read(data->reg_flag_nf, &dir);
548 if (ret < 0) {
549 dev_err(&data->client->dev, "register read failed\n");
550 mutex_unlock(&data->lock);
551 return ret;
553 event = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 1,
554 IIO_EV_TYPE_THRESH,
555 (dir ? IIO_EV_DIR_FALLING :
556 IIO_EV_DIR_RISING));
557 iio_push_event(indio_dev, event, data->timestamp);
559 /* Reset the interrupt flag */
560 ret = regmap_field_write(data->reg_flag_psint, 0);
561 if (ret < 0)
562 dev_err(&data->client->dev, "failed to reset interrupts\n");
563 mutex_unlock(&data->lock);
565 return IRQ_HANDLED;
568 static int stk3310_probe(struct i2c_client *client,
569 const struct i2c_device_id *id)
571 int ret;
572 struct iio_dev *indio_dev;
573 struct stk3310_data *data;
575 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
576 if (!indio_dev) {
577 dev_err(&client->dev, "iio allocation failed!\n");
578 return -ENOMEM;
581 data = iio_priv(indio_dev);
582 data->client = client;
583 i2c_set_clientdata(client, indio_dev);
584 mutex_init(&data->lock);
586 ret = stk3310_regmap_init(data);
587 if (ret < 0)
588 return ret;
590 indio_dev->dev.parent = &client->dev;
591 indio_dev->info = &stk3310_info;
592 indio_dev->name = STK3310_DRIVER_NAME;
593 indio_dev->modes = INDIO_DIRECT_MODE;
594 indio_dev->channels = stk3310_channels;
595 indio_dev->num_channels = ARRAY_SIZE(stk3310_channels);
597 ret = stk3310_init(indio_dev);
598 if (ret < 0)
599 return ret;
601 if (client->irq > 0) {
602 ret = devm_request_threaded_irq(&client->dev, client->irq,
603 stk3310_irq_handler,
604 stk3310_irq_event_handler,
605 IRQF_TRIGGER_FALLING |
606 IRQF_ONESHOT,
607 STK3310_EVENT, indio_dev);
608 if (ret < 0) {
609 dev_err(&client->dev, "request irq %d failed\n",
610 client->irq);
611 goto err_standby;
615 ret = iio_device_register(indio_dev);
616 if (ret < 0) {
617 dev_err(&client->dev, "device_register failed\n");
618 goto err_standby;
621 return 0;
623 err_standby:
624 stk3310_set_state(data, STK3310_STATE_STANDBY);
625 return ret;
628 static int stk3310_remove(struct i2c_client *client)
630 struct iio_dev *indio_dev = i2c_get_clientdata(client);
632 iio_device_unregister(indio_dev);
633 return stk3310_set_state(iio_priv(indio_dev), STK3310_STATE_STANDBY);
636 #ifdef CONFIG_PM_SLEEP
637 static int stk3310_suspend(struct device *dev)
639 struct stk3310_data *data;
641 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
643 return stk3310_set_state(data, STK3310_STATE_STANDBY);
646 static int stk3310_resume(struct device *dev)
648 u8 state = 0;
649 struct stk3310_data *data;
651 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
652 if (data->ps_enabled)
653 state |= STK3310_STATE_EN_PS;
654 if (data->als_enabled)
655 state |= STK3310_STATE_EN_ALS;
657 return stk3310_set_state(data, state);
660 static SIMPLE_DEV_PM_OPS(stk3310_pm_ops, stk3310_suspend, stk3310_resume);
662 #define STK3310_PM_OPS (&stk3310_pm_ops)
663 #else
664 #define STK3310_PM_OPS NULL
665 #endif
667 static const struct i2c_device_id stk3310_i2c_id[] = {
668 {"STK3310", 0},
669 {"STK3311", 0},
672 MODULE_DEVICE_TABLE(i2c, stk3310_i2c_id);
674 static const struct acpi_device_id stk3310_acpi_id[] = {
675 {"STK3310", 0},
676 {"STK3311", 0},
680 MODULE_DEVICE_TABLE(acpi, stk3310_acpi_id);
682 static struct i2c_driver stk3310_driver = {
683 .driver = {
684 .name = "stk3310",
685 .pm = STK3310_PM_OPS,
686 .acpi_match_table = ACPI_PTR(stk3310_acpi_id),
688 .probe = stk3310_probe,
689 .remove = stk3310_remove,
690 .id_table = stk3310_i2c_id,
693 module_i2c_driver(stk3310_driver);
695 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
696 MODULE_DESCRIPTION("STK3310 Ambient Light and Proximity Sensor driver");
697 MODULE_LICENSE("GPL v2");