x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / drivers / iio / accel / stk8312.c
blobe31023dc5f1b72bed380cbceb4ae8605e5024669
1 /**
2 * Sensortek STK8312 3-Axis Accelerometer
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 STK8312; 7-bit I2C address: 0x3D.
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/delay.h>
19 #include <linux/iio/buffer.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/trigger.h>
23 #include <linux/iio/triggered_buffer.h>
24 #include <linux/iio/trigger_consumer.h>
26 #define STK8312_REG_XOUT 0x00
27 #define STK8312_REG_YOUT 0x01
28 #define STK8312_REG_ZOUT 0x02
29 #define STK8312_REG_INTSU 0x06
30 #define STK8312_REG_MODE 0x07
31 #define STK8312_REG_SR 0x08
32 #define STK8312_REG_STH 0x13
33 #define STK8312_REG_RESET 0x20
34 #define STK8312_REG_AFECTRL 0x24
35 #define STK8312_REG_OTPADDR 0x3D
36 #define STK8312_REG_OTPDATA 0x3E
37 #define STK8312_REG_OTPCTRL 0x3F
39 #define STK8312_MODE_ACTIVE BIT(0)
40 #define STK8312_MODE_STANDBY 0x00
41 #define STK8312_MODE_INT_AH_PP 0xC0 /* active-high, push-pull */
42 #define STK8312_DREADY_BIT BIT(4)
43 #define STK8312_RNG_6G 1
44 #define STK8312_RNG_SHIFT 6
45 #define STK8312_RNG_MASK GENMASK(7, 6)
46 #define STK8312_SR_MASK GENMASK(2, 0)
47 #define STK8312_SR_400HZ_IDX 0
48 #define STK8312_ALL_CHANNEL_MASK GENMASK(2, 0)
49 #define STK8312_ALL_CHANNEL_SIZE 3
51 #define STK8312_DRIVER_NAME "stk8312"
52 #define STK8312_IRQ_NAME "stk8312_event"
55 * The accelerometer has two measurement ranges:
57 * -6g - +6g (8-bit, signed)
58 * -16g - +16g (8-bit, signed)
60 * scale1 = (6 + 6) * 9.81 / (2^8 - 1) = 0.4616
61 * scale2 = (16 + 16) * 9.81 / (2^8 - 1) = 1.2311
63 #define STK8312_SCALE_AVAIL "0.4616 1.2311"
65 static const int stk8312_scale_table[][2] = {
66 {0, 461600}, {1, 231100}
69 static const struct {
70 int val;
71 int val2;
72 } stk8312_samp_freq_table[] = {
73 {400, 0}, {200, 0}, {100, 0}, {50, 0}, {25, 0},
74 {12, 500000}, {6, 250000}, {3, 125000}
77 #define STK8312_ACCEL_CHANNEL(index, reg, axis) { \
78 .type = IIO_ACCEL, \
79 .address = reg, \
80 .modified = 1, \
81 .channel2 = IIO_MOD_##axis, \
82 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
83 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
84 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
85 .scan_index = index, \
86 .scan_type = { \
87 .sign = 's', \
88 .realbits = 8, \
89 .storagebits = 8, \
90 .endianness = IIO_CPU, \
91 }, \
94 static const struct iio_chan_spec stk8312_channels[] = {
95 STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X),
96 STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y),
97 STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z),
98 IIO_CHAN_SOFT_TIMESTAMP(3),
101 struct stk8312_data {
102 struct i2c_client *client;
103 struct mutex lock;
104 u8 range;
105 u8 sample_rate_idx;
106 u8 mode;
107 struct iio_trigger *dready_trig;
108 bool dready_trigger_on;
109 s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 64-bit timestamp */
112 static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);
114 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("3.125 6.25 12.5 25 50 100 200 400");
116 static struct attribute *stk8312_attributes[] = {
117 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
118 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
119 NULL,
122 static const struct attribute_group stk8312_attribute_group = {
123 .attrs = stk8312_attributes
126 static int stk8312_otp_init(struct stk8312_data *data)
128 int ret;
129 int count = 10;
130 struct i2c_client *client = data->client;
132 ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
133 if (ret < 0)
134 goto exit_err;
135 ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
136 if (ret < 0)
137 goto exit_err;
139 do {
140 usleep_range(1000, 5000);
141 ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
142 if (ret < 0)
143 goto exit_err;
144 count--;
145 } while (!(ret & BIT(7)) && count > 0);
147 if (count == 0) {
148 ret = -ETIMEDOUT;
149 goto exit_err;
152 ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
153 if (ret == 0)
154 ret = -EINVAL;
155 if (ret < 0)
156 goto exit_err;
158 ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_AFECTRL, ret);
159 if (ret < 0)
160 goto exit_err;
161 msleep(150);
163 return 0;
165 exit_err:
166 dev_err(&client->dev, "failed to initialize sensor\n");
167 return ret;
170 static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
172 int ret;
173 struct i2c_client *client = data->client;
175 if (mode == data->mode)
176 return 0;
178 ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode);
179 if (ret < 0) {
180 dev_err(&client->dev, "failed to change sensor mode\n");
181 return ret;
184 data->mode = mode;
185 if (mode & STK8312_MODE_ACTIVE) {
186 /* Need to run OTP sequence before entering active mode */
187 usleep_range(1000, 5000);
188 ret = stk8312_otp_init(data);
191 return ret;
194 static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask)
196 int ret;
197 u8 mode;
198 struct i2c_client *client = data->client;
200 mode = data->mode;
201 /* We need to go in standby mode to modify registers */
202 ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
203 if (ret < 0)
204 return ret;
206 ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask);
207 if (ret < 0) {
208 dev_err(&client->dev, "failed to set interrupts\n");
209 stk8312_set_mode(data, mode);
210 return ret;
213 return stk8312_set_mode(data, mode);
216 static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig,
217 bool state)
219 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
220 struct stk8312_data *data = iio_priv(indio_dev);
221 int ret;
223 if (state)
224 ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT);
225 else
226 ret = stk8312_set_interrupts(data, 0x00);
228 if (ret < 0) {
229 dev_err(&data->client->dev, "failed to set trigger state\n");
230 return ret;
233 data->dready_trigger_on = state;
235 return 0;
238 static const struct iio_trigger_ops stk8312_trigger_ops = {
239 .set_trigger_state = stk8312_data_rdy_trigger_set_state,
240 .owner = THIS_MODULE,
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, 7);
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 .driver_module = THIS_MODULE,
425 .read_raw = stk8312_read_raw,
426 .write_raw = stk8312_write_raw,
427 .attrs = &stk8312_attribute_group,
430 static irqreturn_t stk8312_trigger_handler(int irq, void *p)
432 struct iio_poll_func *pf = p;
433 struct iio_dev *indio_dev = pf->indio_dev;
434 struct stk8312_data *data = iio_priv(indio_dev);
435 int bit, ret, i = 0;
437 mutex_lock(&data->lock);
439 * Do a bulk read if all channels are requested,
440 * from 0x00 (XOUT) to 0x02 (ZOUT)
442 if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) {
443 ret = i2c_smbus_read_i2c_block_data(data->client,
444 STK8312_REG_XOUT,
445 STK8312_ALL_CHANNEL_SIZE,
446 data->buffer);
447 if (ret < STK8312_ALL_CHANNEL_SIZE) {
448 dev_err(&data->client->dev, "register read failed\n");
449 mutex_unlock(&data->lock);
450 goto err;
452 } else {
453 for_each_set_bit(bit, indio_dev->active_scan_mask,
454 indio_dev->masklength) {
455 ret = stk8312_read_accel(data, bit);
456 if (ret < 0) {
457 mutex_unlock(&data->lock);
458 goto err;
460 data->buffer[i++] = ret;
463 mutex_unlock(&data->lock);
465 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
466 pf->timestamp);
467 err:
468 iio_trigger_notify_done(indio_dev->trig);
470 return IRQ_HANDLED;
473 static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private)
475 struct iio_dev *indio_dev = private;
476 struct stk8312_data *data = iio_priv(indio_dev);
478 if (data->dready_trigger_on)
479 iio_trigger_poll(data->dready_trig);
481 return IRQ_HANDLED;
484 static int stk8312_buffer_preenable(struct iio_dev *indio_dev)
486 struct stk8312_data *data = iio_priv(indio_dev);
488 return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
491 static int stk8312_buffer_postdisable(struct iio_dev *indio_dev)
493 struct stk8312_data *data = iio_priv(indio_dev);
495 return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
498 static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = {
499 .preenable = stk8312_buffer_preenable,
500 .postenable = iio_triggered_buffer_postenable,
501 .predisable = iio_triggered_buffer_predisable,
502 .postdisable = stk8312_buffer_postdisable,
505 static int stk8312_probe(struct i2c_client *client,
506 const struct i2c_device_id *id)
508 int ret;
509 struct iio_dev *indio_dev;
510 struct stk8312_data *data;
512 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
513 if (!indio_dev) {
514 dev_err(&client->dev, "iio allocation failed!\n");
515 return -ENOMEM;
518 data = iio_priv(indio_dev);
519 data->client = client;
520 i2c_set_clientdata(client, indio_dev);
521 mutex_init(&data->lock);
523 indio_dev->dev.parent = &client->dev;
524 indio_dev->info = &stk8312_info;
525 indio_dev->name = STK8312_DRIVER_NAME;
526 indio_dev->modes = INDIO_DIRECT_MODE;
527 indio_dev->channels = stk8312_channels;
528 indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);
530 /* A software reset is recommended at power-on */
531 ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
532 if (ret < 0) {
533 dev_err(&client->dev, "failed to reset sensor\n");
534 return ret;
536 data->sample_rate_idx = STK8312_SR_400HZ_IDX;
537 ret = stk8312_set_range(data, STK8312_RNG_6G);
538 if (ret < 0)
539 return ret;
541 ret = stk8312_set_mode(data,
542 STK8312_MODE_INT_AH_PP | STK8312_MODE_ACTIVE);
543 if (ret < 0)
544 return ret;
546 if (client->irq > 0) {
547 ret = devm_request_threaded_irq(&client->dev, client->irq,
548 stk8312_data_rdy_trig_poll,
549 NULL,
550 IRQF_TRIGGER_RISING |
551 IRQF_ONESHOT,
552 STK8312_IRQ_NAME,
553 indio_dev);
554 if (ret < 0) {
555 dev_err(&client->dev, "request irq %d failed\n",
556 client->irq);
557 goto err_power_off;
560 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
561 "%s-dev%d",
562 indio_dev->name,
563 indio_dev->id);
564 if (!data->dready_trig) {
565 ret = -ENOMEM;
566 goto err_power_off;
569 data->dready_trig->dev.parent = &client->dev;
570 data->dready_trig->ops = &stk8312_trigger_ops;
571 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
572 ret = iio_trigger_register(data->dready_trig);
573 if (ret) {
574 dev_err(&client->dev, "iio trigger register failed\n");
575 goto err_power_off;
579 ret = iio_triggered_buffer_setup(indio_dev,
580 iio_pollfunc_store_time,
581 stk8312_trigger_handler,
582 &stk8312_buffer_setup_ops);
583 if (ret < 0) {
584 dev_err(&client->dev, "iio triggered buffer setup failed\n");
585 goto err_trigger_unregister;
588 ret = iio_device_register(indio_dev);
589 if (ret < 0) {
590 dev_err(&client->dev, "device_register failed\n");
591 goto err_buffer_cleanup;
594 return 0;
596 err_buffer_cleanup:
597 iio_triggered_buffer_cleanup(indio_dev);
598 err_trigger_unregister:
599 if (data->dready_trig)
600 iio_trigger_unregister(data->dready_trig);
601 err_power_off:
602 stk8312_set_mode(data, STK8312_MODE_STANDBY);
603 return ret;
606 static int stk8312_remove(struct i2c_client *client)
608 struct iio_dev *indio_dev = i2c_get_clientdata(client);
609 struct stk8312_data *data = iio_priv(indio_dev);
611 iio_device_unregister(indio_dev);
612 iio_triggered_buffer_cleanup(indio_dev);
614 if (data->dready_trig)
615 iio_trigger_unregister(data->dready_trig);
617 return stk8312_set_mode(data, STK8312_MODE_STANDBY);
620 #ifdef CONFIG_PM_SLEEP
621 static int stk8312_suspend(struct device *dev)
623 struct stk8312_data *data;
625 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
627 return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
630 static int stk8312_resume(struct device *dev)
632 struct stk8312_data *data;
634 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
636 return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
639 static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);
641 #define STK8312_PM_OPS (&stk8312_pm_ops)
642 #else
643 #define STK8312_PM_OPS NULL
644 #endif
646 static const struct i2c_device_id stk8312_i2c_id[] = {
647 {"STK8312", 0},
650 MODULE_DEVICE_TABLE(i2c, stk8312_i2c_id);
652 static const struct acpi_device_id stk8312_acpi_id[] = {
653 {"STK8312", 0},
657 MODULE_DEVICE_TABLE(acpi, stk8312_acpi_id);
659 static struct i2c_driver stk8312_driver = {
660 .driver = {
661 .name = STK8312_DRIVER_NAME,
662 .pm = STK8312_PM_OPS,
663 .acpi_match_table = ACPI_PTR(stk8312_acpi_id),
665 .probe = stk8312_probe,
666 .remove = stk8312_remove,
667 .id_table = stk8312_i2c_id,
670 module_i2c_driver(stk8312_driver);
672 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
673 MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
674 MODULE_LICENSE("GPL v2");