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10#include <linux/acpi.h>
11#include <linux/i2c.h>
12#include <linux/interrupt.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/iio/buffer.h>
16#include <linux/iio/iio.h>
17#include <linux/iio/sysfs.h>
18#include <linux/iio/trigger.h>
19#include <linux/iio/triggered_buffer.h>
20#include <linux/iio/trigger_consumer.h>
21
22#define STK8BA50_REG_XOUT 0x02
23#define STK8BA50_REG_YOUT 0x04
24#define STK8BA50_REG_ZOUT 0x06
25#define STK8BA50_REG_RANGE 0x0F
26#define STK8BA50_REG_BWSEL 0x10
27#define STK8BA50_REG_POWMODE 0x11
28#define STK8BA50_REG_SWRST 0x14
29#define STK8BA50_REG_INTEN2 0x17
30#define STK8BA50_REG_INTMAP2 0x1A
31
32#define STK8BA50_MODE_NORMAL 0
33#define STK8BA50_MODE_SUSPEND 1
34#define STK8BA50_MODE_POWERBIT BIT(7)
35#define STK8BA50_DATA_SHIFT 6
36#define STK8BA50_RESET_CMD 0xB6
37#define STK8BA50_SR_1792HZ_IDX 7
38#define STK8BA50_DREADY_INT_MASK 0x10
39#define STK8BA50_DREADY_INT_MAP 0x81
40#define STK8BA50_ALL_CHANNEL_MASK 7
41#define STK8BA50_ALL_CHANNEL_SIZE 6
42
43#define STK8BA50_DRIVER_NAME "stk8ba50"
44#define STK8BA50_IRQ_NAME "stk8ba50_event"
45
46#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
47
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63
64static const struct {
65 u8 reg_val;
66 u32 scale_val;
67} stk8ba50_scale_table[] = {
68 {3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
69};
70
71
72static const struct {
73 u8 reg_val;
74 u16 samp_freq;
75} stk8ba50_samp_freq_table[] = {
76 {0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
77 {0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
78};
79
80
81static const int stk8ba50_channel_table[] = {
82 STK8BA50_REG_XOUT,
83 STK8BA50_REG_YOUT,
84 STK8BA50_REG_ZOUT
85};
86
87struct stk8ba50_data {
88 struct i2c_client *client;
89 struct mutex lock;
90 int range;
91 u8 sample_rate_idx;
92 struct iio_trigger *dready_trig;
93 bool dready_trigger_on;
94
95
96
97
98
99 s16 buffer[8];
100};
101
102#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
103 .type = IIO_ACCEL, \
104 .address = reg, \
105 .modified = 1, \
106 .channel2 = IIO_MOD_##axis, \
107 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
108 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
109 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
110 .scan_index = index, \
111 .scan_type = { \
112 .sign = 's', \
113 .realbits = 10, \
114 .storagebits = 16, \
115 .shift = STK8BA50_DATA_SHIFT, \
116 .endianness = IIO_CPU, \
117 }, \
118}
119
120static const struct iio_chan_spec stk8ba50_channels[] = {
121 STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
122 STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
123 STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
124 IIO_CHAN_SOFT_TIMESTAMP(3),
125};
126
127static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
128
129static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
130
131static struct attribute *stk8ba50_attributes[] = {
132 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
133 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
134 NULL,
135};
136
137static const struct attribute_group stk8ba50_attribute_group = {
138 .attrs = stk8ba50_attributes
139};
140
141static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
142{
143 int ret;
144 struct i2c_client *client = data->client;
145
146 ret = i2c_smbus_read_word_data(client, reg);
147 if (ret < 0) {
148 dev_err(&client->dev, "register read failed\n");
149 return ret;
150 }
151
152 return ret;
153}
154
155static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
156 bool state)
157{
158 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
159 struct stk8ba50_data *data = iio_priv(indio_dev);
160 int ret;
161
162 if (state)
163 ret = i2c_smbus_write_byte_data(data->client,
164 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
165 else
166 ret = i2c_smbus_write_byte_data(data->client,
167 STK8BA50_REG_INTEN2, 0x00);
168
169 if (ret < 0)
170 dev_err(&data->client->dev, "failed to set trigger state\n");
171 else
172 data->dready_trigger_on = state;
173
174 return ret;
175}
176
177static const struct iio_trigger_ops stk8ba50_trigger_ops = {
178 .set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
179};
180
181static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
182{
183 int ret;
184 u8 masked_reg;
185 struct i2c_client *client = data->client;
186
187 ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
188 if (ret < 0)
189 goto exit_err;
190
191 if (mode)
192 masked_reg = ret | STK8BA50_MODE_POWERBIT;
193 else
194 masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
195
196 ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
197 masked_reg);
198 if (ret < 0)
199 goto exit_err;
200
201 return ret;
202
203exit_err:
204 dev_err(&client->dev, "failed to change sensor mode\n");
205 return ret;
206}
207
208static int stk8ba50_read_raw(struct iio_dev *indio_dev,
209 struct iio_chan_spec const *chan,
210 int *val, int *val2, long mask)
211{
212 struct stk8ba50_data *data = iio_priv(indio_dev);
213 int ret;
214
215 switch (mask) {
216 case IIO_CHAN_INFO_RAW:
217 if (iio_buffer_enabled(indio_dev))
218 return -EBUSY;
219 mutex_lock(&data->lock);
220 ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
221 if (ret < 0) {
222 mutex_unlock(&data->lock);
223 return -EINVAL;
224 }
225 ret = stk8ba50_read_accel(data, chan->address);
226 if (ret < 0) {
227 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
228 mutex_unlock(&data->lock);
229 return -EINVAL;
230 }
231 *val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
232 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
233 mutex_unlock(&data->lock);
234 return IIO_VAL_INT;
235 case IIO_CHAN_INFO_SCALE:
236 *val = 0;
237 *val2 = stk8ba50_scale_table[data->range].scale_val;
238 return IIO_VAL_INT_PLUS_MICRO;
239 case IIO_CHAN_INFO_SAMP_FREQ:
240 *val = stk8ba50_samp_freq_table
241 [data->sample_rate_idx].samp_freq;
242 *val2 = 0;
243 return IIO_VAL_INT;
244 }
245
246 return -EINVAL;
247}
248
249static int stk8ba50_write_raw(struct iio_dev *indio_dev,
250 struct iio_chan_spec const *chan,
251 int val, int val2, long mask)
252{
253 int ret;
254 int i;
255 int index = -1;
256 struct stk8ba50_data *data = iio_priv(indio_dev);
257
258 switch (mask) {
259 case IIO_CHAN_INFO_SCALE:
260 if (val != 0)
261 return -EINVAL;
262
263 for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
264 if (val2 == stk8ba50_scale_table[i].scale_val) {
265 index = i;
266 break;
267 }
268 if (index < 0)
269 return -EINVAL;
270
271 ret = i2c_smbus_write_byte_data(data->client,
272 STK8BA50_REG_RANGE,
273 stk8ba50_scale_table[index].reg_val);
274 if (ret < 0)
275 dev_err(&data->client->dev,
276 "failed to set measurement range\n");
277 else
278 data->range = index;
279
280 return ret;
281 case IIO_CHAN_INFO_SAMP_FREQ:
282 for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
283 if (val == stk8ba50_samp_freq_table[i].samp_freq) {
284 index = i;
285 break;
286 }
287 if (index < 0)
288 return -EINVAL;
289
290 ret = i2c_smbus_write_byte_data(data->client,
291 STK8BA50_REG_BWSEL,
292 stk8ba50_samp_freq_table[index].reg_val);
293 if (ret < 0)
294 dev_err(&data->client->dev,
295 "failed to set sampling rate\n");
296 else
297 data->sample_rate_idx = index;
298
299 return ret;
300 }
301
302 return -EINVAL;
303}
304
305static const struct iio_info stk8ba50_info = {
306 .read_raw = stk8ba50_read_raw,
307 .write_raw = stk8ba50_write_raw,
308 .attrs = &stk8ba50_attribute_group,
309};
310
311static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
312{
313 struct iio_poll_func *pf = p;
314 struct iio_dev *indio_dev = pf->indio_dev;
315 struct stk8ba50_data *data = iio_priv(indio_dev);
316 int bit, ret, i = 0;
317
318 mutex_lock(&data->lock);
319
320
321
322
323 if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
324 ret = i2c_smbus_read_i2c_block_data(data->client,
325 STK8BA50_REG_XOUT,
326 STK8BA50_ALL_CHANNEL_SIZE,
327 (u8 *)data->buffer);
328 if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
329 dev_err(&data->client->dev, "register read failed\n");
330 goto err;
331 }
332 } else {
333 for_each_set_bit(bit, indio_dev->active_scan_mask,
334 indio_dev->masklength) {
335 ret = stk8ba50_read_accel(data,
336 stk8ba50_channel_table[bit]);
337 if (ret < 0)
338 goto err;
339
340 data->buffer[i++] = ret;
341 }
342 }
343 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
344 pf->timestamp);
345err:
346 mutex_unlock(&data->lock);
347 iio_trigger_notify_done(indio_dev->trig);
348
349 return IRQ_HANDLED;
350}
351
352static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
353{
354 struct iio_dev *indio_dev = private;
355 struct stk8ba50_data *data = iio_priv(indio_dev);
356
357 if (data->dready_trigger_on)
358 iio_trigger_poll(data->dready_trig);
359
360 return IRQ_HANDLED;
361}
362
363static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
364{
365 struct stk8ba50_data *data = iio_priv(indio_dev);
366
367 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
368}
369
370static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
371{
372 struct stk8ba50_data *data = iio_priv(indio_dev);
373
374 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
375}
376
377static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
378 .preenable = stk8ba50_buffer_preenable,
379 .postenable = iio_triggered_buffer_postenable,
380 .predisable = iio_triggered_buffer_predisable,
381 .postdisable = stk8ba50_buffer_postdisable,
382};
383
384static int stk8ba50_probe(struct i2c_client *client,
385 const struct i2c_device_id *id)
386{
387 int ret;
388 struct iio_dev *indio_dev;
389 struct stk8ba50_data *data;
390
391 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
392 if (!indio_dev) {
393 dev_err(&client->dev, "iio allocation failed!\n");
394 return -ENOMEM;
395 }
396
397 data = iio_priv(indio_dev);
398 data->client = client;
399 i2c_set_clientdata(client, indio_dev);
400 mutex_init(&data->lock);
401
402 indio_dev->dev.parent = &client->dev;
403 indio_dev->info = &stk8ba50_info;
404 indio_dev->name = STK8BA50_DRIVER_NAME;
405 indio_dev->modes = INDIO_DIRECT_MODE;
406 indio_dev->channels = stk8ba50_channels;
407 indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
408
409
410 ret = i2c_smbus_write_byte_data(client,
411 STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
412 if (ret < 0) {
413 dev_err(&client->dev, "failed to reset sensor\n");
414 goto err_power_off;
415 }
416
417
418 data->range = 0;
419
420
421 data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
422
423
424 ret = i2c_smbus_write_byte_data(client,
425 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
426 if (ret < 0) {
427 dev_err(&client->dev, "failed to set up interrupts\n");
428 goto err_power_off;
429 }
430 ret = i2c_smbus_write_byte_data(client,
431 STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
432 if (ret < 0) {
433 dev_err(&client->dev, "failed to set up interrupts\n");
434 goto err_power_off;
435 }
436
437 if (client->irq > 0) {
438 ret = devm_request_threaded_irq(&client->dev, client->irq,
439 stk8ba50_data_rdy_trig_poll,
440 NULL,
441 IRQF_TRIGGER_RISING |
442 IRQF_ONESHOT,
443 STK8BA50_IRQ_NAME,
444 indio_dev);
445 if (ret < 0) {
446 dev_err(&client->dev, "request irq %d failed\n",
447 client->irq);
448 goto err_power_off;
449 }
450
451 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
452 "%s-dev%d",
453 indio_dev->name,
454 indio_dev->id);
455 if (!data->dready_trig) {
456 ret = -ENOMEM;
457 goto err_power_off;
458 }
459
460 data->dready_trig->dev.parent = &client->dev;
461 data->dready_trig->ops = &stk8ba50_trigger_ops;
462 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
463 ret = iio_trigger_register(data->dready_trig);
464 if (ret) {
465 dev_err(&client->dev, "iio trigger register failed\n");
466 goto err_power_off;
467 }
468 }
469
470 ret = iio_triggered_buffer_setup(indio_dev,
471 iio_pollfunc_store_time,
472 stk8ba50_trigger_handler,
473 &stk8ba50_buffer_setup_ops);
474 if (ret < 0) {
475 dev_err(&client->dev, "iio triggered buffer setup failed\n");
476 goto err_trigger_unregister;
477 }
478
479 ret = iio_device_register(indio_dev);
480 if (ret < 0) {
481 dev_err(&client->dev, "device_register failed\n");
482 goto err_buffer_cleanup;
483 }
484
485 return ret;
486
487err_buffer_cleanup:
488 iio_triggered_buffer_cleanup(indio_dev);
489err_trigger_unregister:
490 if (data->dready_trig)
491 iio_trigger_unregister(data->dready_trig);
492err_power_off:
493 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
494 return ret;
495}
496
497static int stk8ba50_remove(struct i2c_client *client)
498{
499 struct iio_dev *indio_dev = i2c_get_clientdata(client);
500 struct stk8ba50_data *data = iio_priv(indio_dev);
501
502 iio_device_unregister(indio_dev);
503 iio_triggered_buffer_cleanup(indio_dev);
504
505 if (data->dready_trig)
506 iio_trigger_unregister(data->dready_trig);
507
508 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
509}
510
511#ifdef CONFIG_PM_SLEEP
512static int stk8ba50_suspend(struct device *dev)
513{
514 struct stk8ba50_data *data;
515
516 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
517
518 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
519}
520
521static int stk8ba50_resume(struct device *dev)
522{
523 struct stk8ba50_data *data;
524
525 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
526
527 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
528}
529
530static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
531
532#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
533#else
534#define STK8BA50_PM_OPS NULL
535#endif
536
537static const struct i2c_device_id stk8ba50_i2c_id[] = {
538 {"stk8ba50", 0},
539 {}
540};
541MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
542
543static const struct acpi_device_id stk8ba50_acpi_id[] = {
544 {"STK8BA50", 0},
545 {}
546};
547
548MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
549
550static struct i2c_driver stk8ba50_driver = {
551 .driver = {
552 .name = "stk8ba50",
553 .pm = STK8BA50_PM_OPS,
554 .acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
555 },
556 .probe = stk8ba50_probe,
557 .remove = stk8ba50_remove,
558 .id_table = stk8ba50_i2c_id,
559};
560
561module_i2c_driver(stk8ba50_driver);
562
563MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
564MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
565MODULE_LICENSE("GPL v2");
566
