module: Convert symbol namespace to string literal
[linux.git] / drivers / iio / accel / stk8312.c
blob471c154c3631b03bcdba01004dd172e7b3578e89
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Sensortek STK8312 3-Axis Accelerometer
5 * Copyright (c) 2015, Intel Corporation.
7 * IIO driver for STK8312; 7-bit I2C address: 0x3D.
8 */
10 #include <linux/i2c.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/delay.h>
15 #include <linux/types.h>
16 #include <linux/iio/buffer.h>
17 #include <linux/iio/iio.h>
18 #include <linux/iio/sysfs.h>
19 #include <linux/iio/trigger.h>
20 #include <linux/iio/triggered_buffer.h>
21 #include <linux/iio/trigger_consumer.h>
23 #define STK8312_REG_XOUT 0x00
24 #define STK8312_REG_YOUT 0x01
25 #define STK8312_REG_ZOUT 0x02
26 #define STK8312_REG_INTSU 0x06
27 #define STK8312_REG_MODE 0x07
28 #define STK8312_REG_SR 0x08
29 #define STK8312_REG_STH 0x13
30 #define STK8312_REG_RESET 0x20
31 #define STK8312_REG_AFECTRL 0x24
32 #define STK8312_REG_OTPADDR 0x3D
33 #define STK8312_REG_OTPDATA 0x3E
34 #define STK8312_REG_OTPCTRL 0x3F
36 #define STK8312_MODE_ACTIVE BIT(0)
37 #define STK8312_MODE_STANDBY 0x00
38 #define STK8312_MODE_INT_AH_PP 0xC0 /* active-high, push-pull */
39 #define STK8312_DREADY_BIT BIT(4)
40 #define STK8312_RNG_6G 1
41 #define STK8312_RNG_SHIFT 6
42 #define STK8312_RNG_MASK GENMASK(7, 6)
43 #define STK8312_SR_MASK GENMASK(2, 0)
44 #define STK8312_SR_400HZ_IDX 0
45 #define STK8312_ALL_CHANNEL_MASK GENMASK(2, 0)
46 #define STK8312_ALL_CHANNEL_SIZE 3
48 #define STK8312_DRIVER_NAME "stk8312"
49 #define STK8312_IRQ_NAME "stk8312_event"
52 * The accelerometer has two measurement ranges:
54 * -6g - +6g (8-bit, signed)
55 * -16g - +16g (8-bit, signed)
57 * scale1 = (6 + 6) * 9.81 / (2^8 - 1) = 0.4616
58 * scale2 = (16 + 16) * 9.81 / (2^8 - 1) = 1.2311
60 #define STK8312_SCALE_AVAIL "0.4616 1.2311"
62 static const int stk8312_scale_table[][2] = {
63 {0, 461600}, {1, 231100}
66 static const struct {
67 int val;
68 int val2;
69 } stk8312_samp_freq_table[] = {
70 {400, 0}, {200, 0}, {100, 0}, {50, 0}, {25, 0},
71 {12, 500000}, {6, 250000}, {3, 125000}
74 #define STK8312_ACCEL_CHANNEL(index, reg, axis) { \
75 .type = IIO_ACCEL, \
76 .address = reg, \
77 .modified = 1, \
78 .channel2 = IIO_MOD_##axis, \
79 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
80 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
81 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
82 .scan_index = index, \
83 .scan_type = { \
84 .sign = 's', \
85 .realbits = 8, \
86 .storagebits = 8, \
87 .endianness = IIO_CPU, \
88 }, \
91 static const struct iio_chan_spec stk8312_channels[] = {
92 STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X),
93 STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y),
94 STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z),
95 IIO_CHAN_SOFT_TIMESTAMP(3),
98 struct stk8312_data {
99 struct i2c_client *client;
100 struct mutex lock;
101 u8 range;
102 u8 sample_rate_idx;
103 u8 mode;
104 struct iio_trigger *dready_trig;
105 bool dready_trigger_on;
106 /* Ensure timestamp is naturally aligned */
107 struct {
108 s8 chans[3];
109 aligned_s64 timestamp;
110 } scan;
113 static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);
115 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("3.125 6.25 12.5 25 50 100 200 400");
117 static struct attribute *stk8312_attributes[] = {
118 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
119 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
120 NULL,
123 static const struct attribute_group stk8312_attribute_group = {
124 .attrs = stk8312_attributes
127 static int stk8312_otp_init(struct stk8312_data *data)
129 int ret;
130 int count = 10;
131 struct i2c_client *client = data->client;
133 ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
134 if (ret < 0)
135 goto exit_err;
136 ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
137 if (ret < 0)
138 goto exit_err;
140 do {
141 usleep_range(1000, 5000);
142 ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
143 if (ret < 0)
144 goto exit_err;
145 count--;
146 } while (!(ret & BIT(7)) && count > 0);
148 if (count == 0) {
149 ret = -ETIMEDOUT;
150 goto exit_err;
153 ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
154 if (ret == 0)
155 ret = -EINVAL;
156 if (ret < 0)
157 goto exit_err;
159 ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_AFECTRL, ret);
160 if (ret < 0)
161 goto exit_err;
162 msleep(150);
164 return 0;
166 exit_err:
167 dev_err(&client->dev, "failed to initialize sensor\n");
168 return ret;
171 static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
173 int ret;
174 struct i2c_client *client = data->client;
176 if (mode == data->mode)
177 return 0;
179 ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode);
180 if (ret < 0) {
181 dev_err(&client->dev, "failed to change sensor mode\n");
182 return ret;
185 data->mode = mode;
186 if (mode & STK8312_MODE_ACTIVE) {
187 /* Need to run OTP sequence before entering active mode */
188 usleep_range(1000, 5000);
189 ret = stk8312_otp_init(data);
192 return ret;
195 static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask)
197 int ret;
198 u8 mode;
199 struct i2c_client *client = data->client;
201 mode = data->mode;
202 /* We need to go in standby mode to modify registers */
203 ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
204 if (ret < 0)
205 return ret;
207 ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask);
208 if (ret < 0) {
209 dev_err(&client->dev, "failed to set interrupts\n");
210 stk8312_set_mode(data, mode);
211 return ret;
214 return stk8312_set_mode(data, mode);
217 static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig,
218 bool state)
220 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
221 struct stk8312_data *data = iio_priv(indio_dev);
222 int ret;
224 if (state)
225 ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT);
226 else
227 ret = stk8312_set_interrupts(data, 0x00);
229 if (ret < 0) {
230 dev_err(&data->client->dev, "failed to set trigger state\n");
231 return ret;
234 data->dready_trigger_on = state;
236 return 0;
239 static const struct iio_trigger_ops stk8312_trigger_ops = {
240 .set_trigger_state = stk8312_data_rdy_trigger_set_state,
243 static int stk8312_set_sample_rate(struct stk8312_data *data, u8 rate)
245 int ret;
246 u8 masked_reg;
247 u8 mode;
248 struct i2c_client *client = data->client;
250 if (rate == data->sample_rate_idx)
251 return 0;
253 mode = data->mode;
254 /* We need to go in standby mode to modify registers */
255 ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
256 if (ret < 0)
257 return ret;
259 ret = i2c_smbus_read_byte_data(client, STK8312_REG_SR);
260 if (ret < 0)
261 goto err_activate;
263 masked_reg = (ret & (~STK8312_SR_MASK)) | rate;
265 ret = i2c_smbus_write_byte_data(client, STK8312_REG_SR, masked_reg);
266 if (ret < 0)
267 goto err_activate;
269 data->sample_rate_idx = rate;
271 return stk8312_set_mode(data, mode);
273 err_activate:
274 dev_err(&client->dev, "failed to set sampling rate\n");
275 stk8312_set_mode(data, mode);
277 return ret;
280 static int stk8312_set_range(struct stk8312_data *data, u8 range)
282 int ret;
283 u8 masked_reg;
284 u8 mode;
285 struct i2c_client *client = data->client;
287 if (range != 1 && range != 2)
288 return -EINVAL;
289 else if (range == data->range)
290 return 0;
292 mode = data->mode;
293 /* We need to go in standby mode to modify registers */
294 ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
295 if (ret < 0)
296 return ret;
298 ret = i2c_smbus_read_byte_data(client, STK8312_REG_STH);
299 if (ret < 0)
300 goto err_activate;
302 masked_reg = ret & (~STK8312_RNG_MASK);
303 masked_reg |= range << STK8312_RNG_SHIFT;
305 ret = i2c_smbus_write_byte_data(client, STK8312_REG_STH, masked_reg);
306 if (ret < 0)
307 goto err_activate;
309 data->range = range;
311 return stk8312_set_mode(data, mode);
313 err_activate:
314 dev_err(&client->dev, "failed to change sensor range\n");
315 stk8312_set_mode(data, mode);
317 return ret;
320 static int stk8312_read_accel(struct stk8312_data *data, u8 address)
322 int ret;
323 struct i2c_client *client = data->client;
325 if (address > 2)
326 return -EINVAL;
328 ret = i2c_smbus_read_byte_data(client, address);
329 if (ret < 0)
330 dev_err(&client->dev, "register read failed\n");
332 return ret;
335 static int stk8312_read_raw(struct iio_dev *indio_dev,
336 struct iio_chan_spec const *chan,
337 int *val, int *val2, long mask)
339 struct stk8312_data *data = iio_priv(indio_dev);
340 int ret;
342 switch (mask) {
343 case IIO_CHAN_INFO_RAW:
344 if (iio_buffer_enabled(indio_dev))
345 return -EBUSY;
346 mutex_lock(&data->lock);
347 ret = stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
348 if (ret < 0) {
349 mutex_unlock(&data->lock);
350 return ret;
352 ret = stk8312_read_accel(data, chan->address);
353 if (ret < 0) {
354 stk8312_set_mode(data,
355 data->mode & (~STK8312_MODE_ACTIVE));
356 mutex_unlock(&data->lock);
357 return ret;
359 *val = sign_extend32(ret, chan->scan_type.realbits - 1);
360 ret = stk8312_set_mode(data,
361 data->mode & (~STK8312_MODE_ACTIVE));
362 mutex_unlock(&data->lock);
363 if (ret < 0)
364 return ret;
365 return IIO_VAL_INT;
366 case IIO_CHAN_INFO_SCALE:
367 *val = stk8312_scale_table[data->range - 1][0];
368 *val2 = stk8312_scale_table[data->range - 1][1];
369 return IIO_VAL_INT_PLUS_MICRO;
370 case IIO_CHAN_INFO_SAMP_FREQ:
371 *val = stk8312_samp_freq_table[data->sample_rate_idx].val;
372 *val2 = stk8312_samp_freq_table[data->sample_rate_idx].val2;
373 return IIO_VAL_INT_PLUS_MICRO;
376 return -EINVAL;
379 static int stk8312_write_raw(struct iio_dev *indio_dev,
380 struct iio_chan_spec const *chan,
381 int val, int val2, long mask)
383 int i;
384 int index = -1;
385 int ret;
386 struct stk8312_data *data = iio_priv(indio_dev);
388 switch (mask) {
389 case IIO_CHAN_INFO_SCALE:
390 for (i = 0; i < ARRAY_SIZE(stk8312_scale_table); i++)
391 if (val == stk8312_scale_table[i][0] &&
392 val2 == stk8312_scale_table[i][1]) {
393 index = i + 1;
394 break;
396 if (index < 0)
397 return -EINVAL;
399 mutex_lock(&data->lock);
400 ret = stk8312_set_range(data, index);
401 mutex_unlock(&data->lock);
403 return ret;
404 case IIO_CHAN_INFO_SAMP_FREQ:
405 for (i = 0; i < ARRAY_SIZE(stk8312_samp_freq_table); i++)
406 if (val == stk8312_samp_freq_table[i].val &&
407 val2 == stk8312_samp_freq_table[i].val2) {
408 index = i;
409 break;
411 if (index < 0)
412 return -EINVAL;
413 mutex_lock(&data->lock);
414 ret = stk8312_set_sample_rate(data, index);
415 mutex_unlock(&data->lock);
417 return ret;
420 return -EINVAL;
423 static const struct iio_info stk8312_info = {
424 .read_raw = stk8312_read_raw,
425 .write_raw = stk8312_write_raw,
426 .attrs = &stk8312_attribute_group,
429 static irqreturn_t stk8312_trigger_handler(int irq, void *p)
431 struct iio_poll_func *pf = p;
432 struct iio_dev *indio_dev = pf->indio_dev;
433 struct stk8312_data *data = iio_priv(indio_dev);
434 int bit, ret, i = 0;
436 mutex_lock(&data->lock);
438 * Do a bulk read if all channels are requested,
439 * from 0x00 (XOUT) to 0x02 (ZOUT)
441 if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) {
442 ret = i2c_smbus_read_i2c_block_data(data->client,
443 STK8312_REG_XOUT,
444 STK8312_ALL_CHANNEL_SIZE,
445 data->scan.chans);
446 if (ret < STK8312_ALL_CHANNEL_SIZE) {
447 dev_err(&data->client->dev, "register read failed\n");
448 mutex_unlock(&data->lock);
449 goto err;
451 } else {
452 iio_for_each_active_channel(indio_dev, bit) {
453 ret = stk8312_read_accel(data, bit);
454 if (ret < 0) {
455 mutex_unlock(&data->lock);
456 goto err;
458 data->scan.chans[i++] = ret;
461 mutex_unlock(&data->lock);
463 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
464 pf->timestamp);
465 err:
466 iio_trigger_notify_done(indio_dev->trig);
468 return IRQ_HANDLED;
471 static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private)
473 struct iio_dev *indio_dev = private;
474 struct stk8312_data *data = iio_priv(indio_dev);
476 if (data->dready_trigger_on)
477 iio_trigger_poll(data->dready_trig);
479 return IRQ_HANDLED;
482 static int stk8312_buffer_preenable(struct iio_dev *indio_dev)
484 struct stk8312_data *data = iio_priv(indio_dev);
486 return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
489 static int stk8312_buffer_postdisable(struct iio_dev *indio_dev)
491 struct stk8312_data *data = iio_priv(indio_dev);
493 return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
496 static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = {
497 .preenable = stk8312_buffer_preenable,
498 .postdisable = stk8312_buffer_postdisable,
501 static int stk8312_probe(struct i2c_client *client)
503 int ret;
504 struct iio_dev *indio_dev;
505 struct stk8312_data *data;
507 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
508 if (!indio_dev) {
509 dev_err(&client->dev, "iio allocation failed!\n");
510 return -ENOMEM;
513 data = iio_priv(indio_dev);
514 data->client = client;
515 i2c_set_clientdata(client, indio_dev);
516 mutex_init(&data->lock);
518 indio_dev->info = &stk8312_info;
519 indio_dev->name = STK8312_DRIVER_NAME;
520 indio_dev->modes = INDIO_DIRECT_MODE;
521 indio_dev->channels = stk8312_channels;
522 indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);
524 /* A software reset is recommended at power-on */
525 ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
526 if (ret < 0) {
527 dev_err(&client->dev, "failed to reset sensor\n");
528 return ret;
530 data->sample_rate_idx = STK8312_SR_400HZ_IDX;
531 ret = stk8312_set_range(data, STK8312_RNG_6G);
532 if (ret < 0)
533 return ret;
535 ret = stk8312_set_mode(data,
536 STK8312_MODE_INT_AH_PP | STK8312_MODE_ACTIVE);
537 if (ret < 0)
538 return ret;
540 if (client->irq > 0) {
541 ret = devm_request_threaded_irq(&client->dev, client->irq,
542 stk8312_data_rdy_trig_poll,
543 NULL,
544 IRQF_TRIGGER_RISING |
545 IRQF_ONESHOT,
546 STK8312_IRQ_NAME,
547 indio_dev);
548 if (ret < 0) {
549 dev_err(&client->dev, "request irq %d failed\n",
550 client->irq);
551 goto err_power_off;
554 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
555 "%s-dev%d",
556 indio_dev->name,
557 iio_device_id(indio_dev));
558 if (!data->dready_trig) {
559 ret = -ENOMEM;
560 goto err_power_off;
563 data->dready_trig->ops = &stk8312_trigger_ops;
564 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
565 ret = iio_trigger_register(data->dready_trig);
566 if (ret) {
567 dev_err(&client->dev, "iio trigger register failed\n");
568 goto err_power_off;
572 ret = iio_triggered_buffer_setup(indio_dev,
573 iio_pollfunc_store_time,
574 stk8312_trigger_handler,
575 &stk8312_buffer_setup_ops);
576 if (ret < 0) {
577 dev_err(&client->dev, "iio triggered buffer setup failed\n");
578 goto err_trigger_unregister;
581 ret = iio_device_register(indio_dev);
582 if (ret < 0) {
583 dev_err(&client->dev, "device_register failed\n");
584 goto err_buffer_cleanup;
587 return 0;
589 err_buffer_cleanup:
590 iio_triggered_buffer_cleanup(indio_dev);
591 err_trigger_unregister:
592 if (data->dready_trig)
593 iio_trigger_unregister(data->dready_trig);
594 err_power_off:
595 stk8312_set_mode(data, STK8312_MODE_STANDBY);
596 return ret;
599 static void stk8312_remove(struct i2c_client *client)
601 struct iio_dev *indio_dev = i2c_get_clientdata(client);
602 struct stk8312_data *data = iio_priv(indio_dev);
604 iio_device_unregister(indio_dev);
605 iio_triggered_buffer_cleanup(indio_dev);
607 if (data->dready_trig)
608 iio_trigger_unregister(data->dready_trig);
610 stk8312_set_mode(data, STK8312_MODE_STANDBY);
613 static int stk8312_suspend(struct device *dev)
615 struct stk8312_data *data;
617 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
619 return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
622 static int stk8312_resume(struct device *dev)
624 struct stk8312_data *data;
626 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
628 return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
631 static DEFINE_SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend,
632 stk8312_resume);
634 static const struct i2c_device_id stk8312_i2c_id[] = {
635 /* Deprecated in favour of lowercase form */
636 { "STK8312" },
637 { "stk8312" },
640 MODULE_DEVICE_TABLE(i2c, stk8312_i2c_id);
642 static struct i2c_driver stk8312_driver = {
643 .driver = {
644 .name = STK8312_DRIVER_NAME,
645 .pm = pm_sleep_ptr(&stk8312_pm_ops),
647 .probe = stk8312_probe,
648 .remove = stk8312_remove,
649 .id_table = stk8312_i2c_id,
652 module_i2c_driver(stk8312_driver);
654 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
655 MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
656 MODULE_LICENSE("GPL v2");