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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/iio/buffer.h>
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21#include <linux/iio/trigger.h>
22#include <linux/iio/triggered_buffer.h>
23#include <linux/iio/trigger_consumer.h>
24
25#define STK8BA50_REG_XOUT 0x02
26#define STK8BA50_REG_YOUT 0x04
27#define STK8BA50_REG_ZOUT 0x06
28#define STK8BA50_REG_RANGE 0x0F
29#define STK8BA50_REG_BWSEL 0x10
30#define STK8BA50_REG_POWMODE 0x11
31#define STK8BA50_REG_SWRST 0x14
32#define STK8BA50_REG_INTEN2 0x17
33#define STK8BA50_REG_INTMAP2 0x1A
34
35#define STK8BA50_MODE_NORMAL 0
36#define STK8BA50_MODE_SUSPEND 1
37#define STK8BA50_MODE_POWERBIT BIT(7)
38#define STK8BA50_DATA_SHIFT 6
39#define STK8BA50_RESET_CMD 0xB6
40#define STK8BA50_SR_1792HZ_IDX 7
41#define STK8BA50_DREADY_INT_MASK 0x10
42#define STK8BA50_DREADY_INT_MAP 0x81
43#define STK8BA50_ALL_CHANNEL_MASK 7
44#define STK8BA50_ALL_CHANNEL_SIZE 6
45
46#define STK8BA50_DRIVER_NAME "stk8ba50"
47#define STK8BA50_IRQ_NAME "stk8ba50_event"
48
49#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
50
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66
67static const struct {
68 u8 reg_val;
69 u32 scale_val;
70} stk8ba50_scale_table[] = {
71 {3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
72};
73
74
75static const struct {
76 u8 reg_val;
77 u16 samp_freq;
78} stk8ba50_samp_freq_table[] = {
79 {0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
80 {0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
81};
82
83
84static const int stk8ba50_channel_table[] = {
85 STK8BA50_REG_XOUT,
86 STK8BA50_REG_YOUT,
87 STK8BA50_REG_ZOUT
88};
89
90struct stk8ba50_data {
91 struct i2c_client *client;
92 struct mutex lock;
93 int range;
94 u8 sample_rate_idx;
95 struct iio_trigger *dready_trig;
96 bool dready_trigger_on;
97
98
99
100
101
102 s16 buffer[8];
103};
104
105#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
106 .type = IIO_ACCEL, \
107 .address = reg, \
108 .modified = 1, \
109 .channel2 = IIO_MOD_##axis, \
110 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
111 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
112 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
113 .scan_index = index, \
114 .scan_type = { \
115 .sign = 's', \
116 .realbits = 10, \
117 .storagebits = 16, \
118 .shift = STK8BA50_DATA_SHIFT, \
119 .endianness = IIO_CPU, \
120 }, \
121}
122
123static const struct iio_chan_spec stk8ba50_channels[] = {
124 STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
125 STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
126 STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
127 IIO_CHAN_SOFT_TIMESTAMP(3),
128};
129
130static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
131
132static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
133
134static struct attribute *stk8ba50_attributes[] = {
135 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
136 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
137 NULL,
138};
139
140static const struct attribute_group stk8ba50_attribute_group = {
141 .attrs = stk8ba50_attributes
142};
143
144static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
145{
146 int ret;
147 struct i2c_client *client = data->client;
148
149 ret = i2c_smbus_read_word_data(client, reg);
150 if (ret < 0) {
151 dev_err(&client->dev, "register read failed\n");
152 return ret;
153 }
154
155 return ret;
156}
157
158static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
159 bool state)
160{
161 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
162 struct stk8ba50_data *data = iio_priv(indio_dev);
163 int ret;
164
165 if (state)
166 ret = i2c_smbus_write_byte_data(data->client,
167 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
168 else
169 ret = i2c_smbus_write_byte_data(data->client,
170 STK8BA50_REG_INTEN2, 0x00);
171
172 if (ret < 0)
173 dev_err(&data->client->dev, "failed to set trigger state\n");
174 else
175 data->dready_trigger_on = state;
176
177 return ret;
178}
179
180static const struct iio_trigger_ops stk8ba50_trigger_ops = {
181 .set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
182 .owner = THIS_MODULE,
183};
184
185static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
186{
187 int ret;
188 u8 masked_reg;
189 struct i2c_client *client = data->client;
190
191 ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
192 if (ret < 0)
193 goto exit_err;
194
195 if (mode)
196 masked_reg = ret | STK8BA50_MODE_POWERBIT;
197 else
198 masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
199
200 ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
201 masked_reg);
202 if (ret < 0)
203 goto exit_err;
204
205 return ret;
206
207exit_err:
208 dev_err(&client->dev, "failed to change sensor mode\n");
209 return ret;
210}
211
212static int stk8ba50_read_raw(struct iio_dev *indio_dev,
213 struct iio_chan_spec const *chan,
214 int *val, int *val2, long mask)
215{
216 struct stk8ba50_data *data = iio_priv(indio_dev);
217 int ret;
218
219 switch (mask) {
220 case IIO_CHAN_INFO_RAW:
221 if (iio_buffer_enabled(indio_dev))
222 return -EBUSY;
223 mutex_lock(&data->lock);
224 ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
225 if (ret < 0) {
226 mutex_unlock(&data->lock);
227 return -EINVAL;
228 }
229 ret = stk8ba50_read_accel(data, chan->address);
230 if (ret < 0) {
231 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
232 mutex_unlock(&data->lock);
233 return -EINVAL;
234 }
235 *val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
236 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
237 mutex_unlock(&data->lock);
238 return IIO_VAL_INT;
239 case IIO_CHAN_INFO_SCALE:
240 *val = 0;
241 *val2 = stk8ba50_scale_table[data->range].scale_val;
242 return IIO_VAL_INT_PLUS_MICRO;
243 case IIO_CHAN_INFO_SAMP_FREQ:
244 *val = stk8ba50_samp_freq_table
245 [data->sample_rate_idx].samp_freq;
246 *val2 = 0;
247 return IIO_VAL_INT;
248 }
249
250 return -EINVAL;
251}
252
253static int stk8ba50_write_raw(struct iio_dev *indio_dev,
254 struct iio_chan_spec const *chan,
255 int val, int val2, long mask)
256{
257 int ret;
258 int i;
259 int index = -1;
260 struct stk8ba50_data *data = iio_priv(indio_dev);
261
262 switch (mask) {
263 case IIO_CHAN_INFO_SCALE:
264 if (val != 0)
265 return -EINVAL;
266
267 for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
268 if (val2 == stk8ba50_scale_table[i].scale_val) {
269 index = i;
270 break;
271 }
272 if (index < 0)
273 return -EINVAL;
274
275 ret = i2c_smbus_write_byte_data(data->client,
276 STK8BA50_REG_RANGE,
277 stk8ba50_scale_table[index].reg_val);
278 if (ret < 0)
279 dev_err(&data->client->dev,
280 "failed to set measurement range\n");
281 else
282 data->range = index;
283
284 return ret;
285 case IIO_CHAN_INFO_SAMP_FREQ:
286 for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
287 if (val == stk8ba50_samp_freq_table[i].samp_freq) {
288 index = i;
289 break;
290 }
291 if (index < 0)
292 return -EINVAL;
293
294 ret = i2c_smbus_write_byte_data(data->client,
295 STK8BA50_REG_BWSEL,
296 stk8ba50_samp_freq_table[index].reg_val);
297 if (ret < 0)
298 dev_err(&data->client->dev,
299 "failed to set sampling rate\n");
300 else
301 data->sample_rate_idx = index;
302
303 return ret;
304 }
305
306 return -EINVAL;
307}
308
309static const struct iio_info stk8ba50_info = {
310 .driver_module = THIS_MODULE,
311 .read_raw = stk8ba50_read_raw,
312 .write_raw = stk8ba50_write_raw,
313 .attrs = &stk8ba50_attribute_group,
314};
315
316static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
317{
318 struct iio_poll_func *pf = p;
319 struct iio_dev *indio_dev = pf->indio_dev;
320 struct stk8ba50_data *data = iio_priv(indio_dev);
321 int bit, ret, i = 0;
322
323 mutex_lock(&data->lock);
324
325
326
327
328 if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
329 ret = i2c_smbus_read_i2c_block_data(data->client,
330 STK8BA50_REG_XOUT,
331 STK8BA50_ALL_CHANNEL_SIZE,
332 (u8 *)data->buffer);
333 if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
334 dev_err(&data->client->dev, "register read failed\n");
335 goto err;
336 }
337 } else {
338 for_each_set_bit(bit, indio_dev->active_scan_mask,
339 indio_dev->masklength) {
340 ret = stk8ba50_read_accel(data,
341 stk8ba50_channel_table[bit]);
342 if (ret < 0)
343 goto err;
344
345 data->buffer[i++] = ret;
346 }
347 }
348 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
349 pf->timestamp);
350err:
351 mutex_unlock(&data->lock);
352 iio_trigger_notify_done(indio_dev->trig);
353
354 return IRQ_HANDLED;
355}
356
357static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
358{
359 struct iio_dev *indio_dev = private;
360 struct stk8ba50_data *data = iio_priv(indio_dev);
361
362 if (data->dready_trigger_on)
363 iio_trigger_poll(data->dready_trig);
364
365 return IRQ_HANDLED;
366}
367
368static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
369{
370 struct stk8ba50_data *data = iio_priv(indio_dev);
371
372 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
373}
374
375static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
376{
377 struct stk8ba50_data *data = iio_priv(indio_dev);
378
379 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
380}
381
382static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
383 .preenable = stk8ba50_buffer_preenable,
384 .postenable = iio_triggered_buffer_postenable,
385 .predisable = iio_triggered_buffer_predisable,
386 .postdisable = stk8ba50_buffer_postdisable,
387};
388
389static int stk8ba50_probe(struct i2c_client *client,
390 const struct i2c_device_id *id)
391{
392 int ret;
393 struct iio_dev *indio_dev;
394 struct stk8ba50_data *data;
395
396 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
397 if (!indio_dev) {
398 dev_err(&client->dev, "iio allocation failed!\n");
399 return -ENOMEM;
400 }
401
402 data = iio_priv(indio_dev);
403 data->client = client;
404 i2c_set_clientdata(client, indio_dev);
405 mutex_init(&data->lock);
406
407 indio_dev->dev.parent = &client->dev;
408 indio_dev->info = &stk8ba50_info;
409 indio_dev->name = STK8BA50_DRIVER_NAME;
410 indio_dev->modes = INDIO_DIRECT_MODE;
411 indio_dev->channels = stk8ba50_channels;
412 indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
413
414
415 ret = i2c_smbus_write_byte_data(client,
416 STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
417 if (ret < 0) {
418 dev_err(&client->dev, "failed to reset sensor\n");
419 goto err_power_off;
420 }
421
422
423 data->range = 0;
424
425
426 data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
427
428
429 ret = i2c_smbus_write_byte_data(client,
430 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
431 if (ret < 0) {
432 dev_err(&client->dev, "failed to set up interrupts\n");
433 goto err_power_off;
434 }
435 ret = i2c_smbus_write_byte_data(client,
436 STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
437 if (ret < 0) {
438 dev_err(&client->dev, "failed to set up interrupts\n");
439 goto err_power_off;
440 }
441
442 if (client->irq > 0) {
443 ret = devm_request_threaded_irq(&client->dev, client->irq,
444 stk8ba50_data_rdy_trig_poll,
445 NULL,
446 IRQF_TRIGGER_RISING |
447 IRQF_ONESHOT,
448 STK8BA50_IRQ_NAME,
449 indio_dev);
450 if (ret < 0) {
451 dev_err(&client->dev, "request irq %d failed\n",
452 client->irq);
453 goto err_power_off;
454 }
455
456 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
457 "%s-dev%d",
458 indio_dev->name,
459 indio_dev->id);
460 if (!data->dready_trig) {
461 ret = -ENOMEM;
462 goto err_power_off;
463 }
464
465 data->dready_trig->dev.parent = &client->dev;
466 data->dready_trig->ops = &stk8ba50_trigger_ops;
467 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
468 ret = iio_trigger_register(data->dready_trig);
469 if (ret) {
470 dev_err(&client->dev, "iio trigger register failed\n");
471 goto err_power_off;
472 }
473 }
474
475 ret = iio_triggered_buffer_setup(indio_dev,
476 iio_pollfunc_store_time,
477 stk8ba50_trigger_handler,
478 &stk8ba50_buffer_setup_ops);
479 if (ret < 0) {
480 dev_err(&client->dev, "iio triggered buffer setup failed\n");
481 goto err_trigger_unregister;
482 }
483
484 ret = iio_device_register(indio_dev);
485 if (ret < 0) {
486 dev_err(&client->dev, "device_register failed\n");
487 goto err_buffer_cleanup;
488 }
489
490 return ret;
491
492err_buffer_cleanup:
493 iio_triggered_buffer_cleanup(indio_dev);
494err_trigger_unregister:
495 if (data->dready_trig)
496 iio_trigger_unregister(data->dready_trig);
497err_power_off:
498 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
499 return ret;
500}
501
502static int stk8ba50_remove(struct i2c_client *client)
503{
504 struct iio_dev *indio_dev = i2c_get_clientdata(client);
505 struct stk8ba50_data *data = iio_priv(indio_dev);
506
507 iio_device_unregister(indio_dev);
508 iio_triggered_buffer_cleanup(indio_dev);
509
510 if (data->dready_trig)
511 iio_trigger_unregister(data->dready_trig);
512
513 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
514}
515
516#ifdef CONFIG_PM_SLEEP
517static int stk8ba50_suspend(struct device *dev)
518{
519 struct stk8ba50_data *data;
520
521 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
522
523 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
524}
525
526static int stk8ba50_resume(struct device *dev)
527{
528 struct stk8ba50_data *data;
529
530 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
531
532 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
533}
534
535static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
536
537#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
538#else
539#define STK8BA50_PM_OPS NULL
540#endif
541
542static const struct i2c_device_id stk8ba50_i2c_id[] = {
543 {"stk8ba50", 0},
544 {}
545};
546MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
547
548static const struct acpi_device_id stk8ba50_acpi_id[] = {
549 {"STK8BA50", 0},
550 {}
551};
552
553MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
554
555static struct i2c_driver stk8ba50_driver = {
556 .driver = {
557 .name = "stk8ba50",
558 .pm = STK8BA50_PM_OPS,
559 .acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
560 },
561 .probe = stk8ba50_probe,
562 .remove = stk8ba50_remove,
563 .id_table = stk8ba50_i2c_id,
564};
565
566module_i2c_driver(stk8ba50_driver);
567
568MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
569MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
570MODULE_LICENSE("GPL v2");
571
