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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 struct {
96 s16 chans[3];
97 s64 timetamp __aligned(8);
98 } scan;
99};
100
101#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
102 .type = IIO_ACCEL, \
103 .address = reg, \
104 .modified = 1, \
105 .channel2 = IIO_MOD_##axis, \
106 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
107 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
108 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
109 .scan_index = index, \
110 .scan_type = { \
111 .sign = 's', \
112 .realbits = 10, \
113 .storagebits = 16, \
114 .shift = STK8BA50_DATA_SHIFT, \
115 .endianness = IIO_CPU, \
116 }, \
117}
118
119static const struct iio_chan_spec stk8ba50_channels[] = {
120 STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
121 STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
122 STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
123 IIO_CHAN_SOFT_TIMESTAMP(3),
124};
125
126static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
127
128static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
129
130static struct attribute *stk8ba50_attributes[] = {
131 &iio_const_attr_in_accel_scale_available.dev_attr.attr,
132 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
133 NULL,
134};
135
136static const struct attribute_group stk8ba50_attribute_group = {
137 .attrs = stk8ba50_attributes
138};
139
140static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
141{
142 int ret;
143 struct i2c_client *client = data->client;
144
145 ret = i2c_smbus_read_word_data(client, reg);
146 if (ret < 0) {
147 dev_err(&client->dev, "register read failed\n");
148 return ret;
149 }
150
151 return ret;
152}
153
154static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
155 bool state)
156{
157 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
158 struct stk8ba50_data *data = iio_priv(indio_dev);
159 int ret;
160
161 if (state)
162 ret = i2c_smbus_write_byte_data(data->client,
163 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
164 else
165 ret = i2c_smbus_write_byte_data(data->client,
166 STK8BA50_REG_INTEN2, 0x00);
167
168 if (ret < 0)
169 dev_err(&data->client->dev, "failed to set trigger state\n");
170 else
171 data->dready_trigger_on = state;
172
173 return ret;
174}
175
176static const struct iio_trigger_ops stk8ba50_trigger_ops = {
177 .set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
178};
179
180static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
181{
182 int ret;
183 u8 masked_reg;
184 struct i2c_client *client = data->client;
185
186 ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
187 if (ret < 0)
188 goto exit_err;
189
190 if (mode)
191 masked_reg = ret | STK8BA50_MODE_POWERBIT;
192 else
193 masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
194
195 ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
196 masked_reg);
197 if (ret < 0)
198 goto exit_err;
199
200 return ret;
201
202exit_err:
203 dev_err(&client->dev, "failed to change sensor mode\n");
204 return ret;
205}
206
207static int stk8ba50_read_raw(struct iio_dev *indio_dev,
208 struct iio_chan_spec const *chan,
209 int *val, int *val2, long mask)
210{
211 struct stk8ba50_data *data = iio_priv(indio_dev);
212 int ret;
213
214 switch (mask) {
215 case IIO_CHAN_INFO_RAW:
216 if (iio_buffer_enabled(indio_dev))
217 return -EBUSY;
218 mutex_lock(&data->lock);
219 ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
220 if (ret < 0) {
221 mutex_unlock(&data->lock);
222 return -EINVAL;
223 }
224 ret = stk8ba50_read_accel(data, chan->address);
225 if (ret < 0) {
226 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
227 mutex_unlock(&data->lock);
228 return -EINVAL;
229 }
230 *val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
231 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
232 mutex_unlock(&data->lock);
233 return IIO_VAL_INT;
234 case IIO_CHAN_INFO_SCALE:
235 *val = 0;
236 *val2 = stk8ba50_scale_table[data->range].scale_val;
237 return IIO_VAL_INT_PLUS_MICRO;
238 case IIO_CHAN_INFO_SAMP_FREQ:
239 *val = stk8ba50_samp_freq_table
240 [data->sample_rate_idx].samp_freq;
241 *val2 = 0;
242 return IIO_VAL_INT;
243 }
244
245 return -EINVAL;
246}
247
248static int stk8ba50_write_raw(struct iio_dev *indio_dev,
249 struct iio_chan_spec const *chan,
250 int val, int val2, long mask)
251{
252 int ret;
253 int i;
254 int index = -1;
255 struct stk8ba50_data *data = iio_priv(indio_dev);
256
257 switch (mask) {
258 case IIO_CHAN_INFO_SCALE:
259 if (val != 0)
260 return -EINVAL;
261
262 for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
263 if (val2 == stk8ba50_scale_table[i].scale_val) {
264 index = i;
265 break;
266 }
267 if (index < 0)
268 return -EINVAL;
269
270 ret = i2c_smbus_write_byte_data(data->client,
271 STK8BA50_REG_RANGE,
272 stk8ba50_scale_table[index].reg_val);
273 if (ret < 0)
274 dev_err(&data->client->dev,
275 "failed to set measurement range\n");
276 else
277 data->range = index;
278
279 return ret;
280 case IIO_CHAN_INFO_SAMP_FREQ:
281 for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
282 if (val == stk8ba50_samp_freq_table[i].samp_freq) {
283 index = i;
284 break;
285 }
286 if (index < 0)
287 return -EINVAL;
288
289 ret = i2c_smbus_write_byte_data(data->client,
290 STK8BA50_REG_BWSEL,
291 stk8ba50_samp_freq_table[index].reg_val);
292 if (ret < 0)
293 dev_err(&data->client->dev,
294 "failed to set sampling rate\n");
295 else
296 data->sample_rate_idx = index;
297
298 return ret;
299 }
300
301 return -EINVAL;
302}
303
304static const struct iio_info stk8ba50_info = {
305 .read_raw = stk8ba50_read_raw,
306 .write_raw = stk8ba50_write_raw,
307 .attrs = &stk8ba50_attribute_group,
308};
309
310static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
311{
312 struct iio_poll_func *pf = p;
313 struct iio_dev *indio_dev = pf->indio_dev;
314 struct stk8ba50_data *data = iio_priv(indio_dev);
315 int bit, ret, i = 0;
316
317 mutex_lock(&data->lock);
318
319
320
321
322 if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
323 ret = i2c_smbus_read_i2c_block_data(data->client,
324 STK8BA50_REG_XOUT,
325 STK8BA50_ALL_CHANNEL_SIZE,
326 (u8 *)data->scan.chans);
327 if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
328 dev_err(&data->client->dev, "register read failed\n");
329 goto err;
330 }
331 } else {
332 for_each_set_bit(bit, indio_dev->active_scan_mask,
333 indio_dev->masklength) {
334 ret = stk8ba50_read_accel(data,
335 stk8ba50_channel_table[bit]);
336 if (ret < 0)
337 goto err;
338
339 data->scan.chans[i++] = ret;
340 }
341 }
342 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
343 pf->timestamp);
344err:
345 mutex_unlock(&data->lock);
346 iio_trigger_notify_done(indio_dev->trig);
347
348 return IRQ_HANDLED;
349}
350
351static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
352{
353 struct iio_dev *indio_dev = private;
354 struct stk8ba50_data *data = iio_priv(indio_dev);
355
356 if (data->dready_trigger_on)
357 iio_trigger_poll(data->dready_trig);
358
359 return IRQ_HANDLED;
360}
361
362static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
363{
364 struct stk8ba50_data *data = iio_priv(indio_dev);
365
366 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
367}
368
369static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
370{
371 struct stk8ba50_data *data = iio_priv(indio_dev);
372
373 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
374}
375
376static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
377 .preenable = stk8ba50_buffer_preenable,
378 .postdisable = stk8ba50_buffer_postdisable,
379};
380
381static int stk8ba50_probe(struct i2c_client *client,
382 const struct i2c_device_id *id)
383{
384 int ret;
385 struct iio_dev *indio_dev;
386 struct stk8ba50_data *data;
387
388 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
389 if (!indio_dev) {
390 dev_err(&client->dev, "iio allocation failed!\n");
391 return -ENOMEM;
392 }
393
394 data = iio_priv(indio_dev);
395 data->client = client;
396 i2c_set_clientdata(client, indio_dev);
397 mutex_init(&data->lock);
398
399 indio_dev->info = &stk8ba50_info;
400 indio_dev->name = STK8BA50_DRIVER_NAME;
401 indio_dev->modes = INDIO_DIRECT_MODE;
402 indio_dev->channels = stk8ba50_channels;
403 indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
404
405
406 ret = i2c_smbus_write_byte_data(client,
407 STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
408 if (ret < 0) {
409 dev_err(&client->dev, "failed to reset sensor\n");
410 goto err_power_off;
411 }
412
413
414 data->range = 0;
415
416
417 data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
418
419
420 ret = i2c_smbus_write_byte_data(client,
421 STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
422 if (ret < 0) {
423 dev_err(&client->dev, "failed to set up interrupts\n");
424 goto err_power_off;
425 }
426 ret = i2c_smbus_write_byte_data(client,
427 STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
428 if (ret < 0) {
429 dev_err(&client->dev, "failed to set up interrupts\n");
430 goto err_power_off;
431 }
432
433 if (client->irq > 0) {
434 ret = devm_request_threaded_irq(&client->dev, client->irq,
435 stk8ba50_data_rdy_trig_poll,
436 NULL,
437 IRQF_TRIGGER_RISING |
438 IRQF_ONESHOT,
439 STK8BA50_IRQ_NAME,
440 indio_dev);
441 if (ret < 0) {
442 dev_err(&client->dev, "request irq %d failed\n",
443 client->irq);
444 goto err_power_off;
445 }
446
447 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
448 "%s-dev%d",
449 indio_dev->name,
450 iio_device_id(indio_dev));
451 if (!data->dready_trig) {
452 ret = -ENOMEM;
453 goto err_power_off;
454 }
455
456 data->dready_trig->ops = &stk8ba50_trigger_ops;
457 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
458 ret = iio_trigger_register(data->dready_trig);
459 if (ret) {
460 dev_err(&client->dev, "iio trigger register failed\n");
461 goto err_power_off;
462 }
463 }
464
465 ret = iio_triggered_buffer_setup(indio_dev,
466 iio_pollfunc_store_time,
467 stk8ba50_trigger_handler,
468 &stk8ba50_buffer_setup_ops);
469 if (ret < 0) {
470 dev_err(&client->dev, "iio triggered buffer setup failed\n");
471 goto err_trigger_unregister;
472 }
473
474 ret = iio_device_register(indio_dev);
475 if (ret < 0) {
476 dev_err(&client->dev, "device_register failed\n");
477 goto err_buffer_cleanup;
478 }
479
480 return ret;
481
482err_buffer_cleanup:
483 iio_triggered_buffer_cleanup(indio_dev);
484err_trigger_unregister:
485 if (data->dready_trig)
486 iio_trigger_unregister(data->dready_trig);
487err_power_off:
488 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
489 return ret;
490}
491
492static int stk8ba50_remove(struct i2c_client *client)
493{
494 struct iio_dev *indio_dev = i2c_get_clientdata(client);
495 struct stk8ba50_data *data = iio_priv(indio_dev);
496
497 iio_device_unregister(indio_dev);
498 iio_triggered_buffer_cleanup(indio_dev);
499
500 if (data->dready_trig)
501 iio_trigger_unregister(data->dready_trig);
502
503 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
504}
505
506#ifdef CONFIG_PM_SLEEP
507static int stk8ba50_suspend(struct device *dev)
508{
509 struct stk8ba50_data *data;
510
511 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
512
513 return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
514}
515
516static int stk8ba50_resume(struct device *dev)
517{
518 struct stk8ba50_data *data;
519
520 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
521
522 return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
523}
524
525static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
526
527#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
528#else
529#define STK8BA50_PM_OPS NULL
530#endif
531
532static const struct i2c_device_id stk8ba50_i2c_id[] = {
533 {"stk8ba50", 0},
534 {}
535};
536MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
537
538static const struct acpi_device_id stk8ba50_acpi_id[] = {
539 {"STK8BA50", 0},
540 {}
541};
542
543MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
544
545static struct i2c_driver stk8ba50_driver = {
546 .driver = {
547 .name = "stk8ba50",
548 .pm = STK8BA50_PM_OPS,
549 .acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
550 },
551 .probe = stk8ba50_probe,
552 .remove = stk8ba50_remove,
553 .id_table = stk8ba50_i2c_id,
554};
555
556module_i2c_driver(stk8ba50_driver);
557
558MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
559MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
560MODULE_LICENSE("GPL v2");
561
