This source file includes following definitions.
- mag3110_request
- mag3110_read
- mag3110_show_int_plus_micros
- mag3110_get_int_plus_micros_index
- mag3110_show_samp_freq_avail
- mag3110_get_samp_freq_index
- mag3110_calculate_sleep
- mag3110_standby
- mag3110_wait_standby
- mag3110_active
- mag3110_is_active
- mag3110_change_config
- mag3110_read_raw
- mag3110_write_raw
- mag3110_trigger_handler
- mag3110_probe
- mag3110_remove
- mag3110_suspend
- mag3110_resume
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12 #include <linux/module.h>
13 #include <linux/i2c.h>
14 #include <linux/iio/iio.h>
15 #include <linux/iio/sysfs.h>
16 #include <linux/iio/trigger_consumer.h>
17 #include <linux/iio/buffer.h>
18 #include <linux/iio/triggered_buffer.h>
19 #include <linux/delay.h>
20 #include <linux/regulator/consumer.h>
21
22 #define MAG3110_STATUS 0x00
23 #define MAG3110_OUT_X 0x01
24 #define MAG3110_OUT_Y 0x03
25 #define MAG3110_OUT_Z 0x05
26 #define MAG3110_WHO_AM_I 0x07
27 #define MAG3110_SYSMOD 0x08
28 #define MAG3110_OFF_X 0x09
29 #define MAG3110_OFF_Y 0x0b
30 #define MAG3110_OFF_Z 0x0d
31 #define MAG3110_DIE_TEMP 0x0f
32 #define MAG3110_CTRL_REG1 0x10
33 #define MAG3110_CTRL_REG2 0x11
34
35 #define MAG3110_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0))
36
37 #define MAG3110_CTRL_DR_MASK (BIT(7) | BIT(6) | BIT(5))
38 #define MAG3110_CTRL_DR_SHIFT 5
39 #define MAG3110_CTRL_DR_DEFAULT 0
40
41 #define MAG3110_SYSMOD_MODE_MASK GENMASK(1, 0)
42
43 #define MAG3110_CTRL_TM BIT(1)
44 #define MAG3110_CTRL_AC BIT(0)
45
46 #define MAG3110_CTRL_AUTO_MRST_EN BIT(7)
47 #define MAG3110_CTRL_RAW BIT(5)
48
49 #define MAG3110_DEVICE_ID 0xc4
50
51
52 struct mag3110_data {
53 struct i2c_client *client;
54 struct mutex lock;
55 u8 ctrl_reg1;
56 int sleep_val;
57 struct regulator *vdd_reg;
58 struct regulator *vddio_reg;
59 };
60
61 static int mag3110_request(struct mag3110_data *data)
62 {
63 int ret, tries = 150;
64
65 if ((data->ctrl_reg1 & MAG3110_CTRL_AC) == 0) {
66
67 ret = i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
68 data->ctrl_reg1 | MAG3110_CTRL_TM);
69 if (ret < 0)
70 return ret;
71 }
72
73 while (tries-- > 0) {
74 ret = i2c_smbus_read_byte_data(data->client, MAG3110_STATUS);
75 if (ret < 0)
76 return ret;
77
78 if ((ret & MAG3110_STATUS_DRDY) == MAG3110_STATUS_DRDY)
79 break;
80
81 if (data->sleep_val <= 20)
82 usleep_range(data->sleep_val * 250, data->sleep_val * 500);
83 else
84 msleep(20);
85 }
86
87 if (tries < 0) {
88 dev_err(&data->client->dev, "data not ready\n");
89 return -EIO;
90 }
91
92 return 0;
93 }
94
95 static int mag3110_read(struct mag3110_data *data, __be16 buf[3])
96 {
97 int ret;
98
99 mutex_lock(&data->lock);
100 ret = mag3110_request(data);
101 if (ret < 0) {
102 mutex_unlock(&data->lock);
103 return ret;
104 }
105 ret = i2c_smbus_read_i2c_block_data(data->client,
106 MAG3110_OUT_X, 3 * sizeof(__be16), (u8 *) buf);
107 mutex_unlock(&data->lock);
108
109 return ret;
110 }
111
112 static ssize_t mag3110_show_int_plus_micros(char *buf,
113 const int (*vals)[2], int n)
114 {
115 size_t len = 0;
116
117 while (n-- > 0)
118 len += scnprintf(buf + len, PAGE_SIZE - len,
119 "%d.%06d ", vals[n][0], vals[n][1]);
120
121
122 buf[len - 1] = '\n';
123
124 return len;
125 }
126
127 static int mag3110_get_int_plus_micros_index(const int (*vals)[2], int n,
128 int val, int val2)
129 {
130 while (n-- > 0)
131 if (val == vals[n][0] && val2 == vals[n][1])
132 return n;
133
134 return -EINVAL;
135 }
136
137 static const int mag3110_samp_freq[8][2] = {
138 {80, 0}, {40, 0}, {20, 0}, {10, 0}, {5, 0}, {2, 500000},
139 {1, 250000}, {0, 625000}
140 };
141
142 static ssize_t mag3110_show_samp_freq_avail(struct device *dev,
143 struct device_attribute *attr, char *buf)
144 {
145 return mag3110_show_int_plus_micros(buf, mag3110_samp_freq, 8);
146 }
147
148 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(mag3110_show_samp_freq_avail);
149
150 static int mag3110_get_samp_freq_index(struct mag3110_data *data,
151 int val, int val2)
152 {
153 return mag3110_get_int_plus_micros_index(mag3110_samp_freq, 8, val,
154 val2);
155 }
156
157 static int mag3110_calculate_sleep(struct mag3110_data *data)
158 {
159 int ret, i = data->ctrl_reg1 >> MAG3110_CTRL_DR_SHIFT;
160
161 if (mag3110_samp_freq[i][0] > 0)
162 ret = 1000 / mag3110_samp_freq[i][0];
163 else
164 ret = 1000;
165
166 return ret == 0 ? 1 : ret;
167 }
168
169 static int mag3110_standby(struct mag3110_data *data)
170 {
171 return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
172 data->ctrl_reg1 & ~MAG3110_CTRL_AC);
173 }
174
175 static int mag3110_wait_standby(struct mag3110_data *data)
176 {
177 int ret, tries = 30;
178
179
180
181
182
183
184 while (tries-- > 0) {
185 ret = i2c_smbus_read_byte_data(data->client, MAG3110_SYSMOD);
186 if (ret < 0) {
187 dev_err(&data->client->dev, "i2c error\n");
188 return ret;
189 }
190
191 if ((ret & MAG3110_SYSMOD_MODE_MASK) == 0)
192 break;
193
194 msleep_interruptible(500);
195 }
196
197 if (tries < 0) {
198 dev_err(&data->client->dev, "device not entering standby mode\n");
199 return -EIO;
200 }
201
202 return 0;
203 }
204
205 static int mag3110_active(struct mag3110_data *data)
206 {
207 return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
208 data->ctrl_reg1);
209 }
210
211
212 static int mag3110_is_active(struct mag3110_data *data)
213 {
214 int reg;
215
216 reg = i2c_smbus_read_byte_data(data->client, MAG3110_CTRL_REG1);
217 if (reg < 0)
218 return reg;
219
220 return reg & MAG3110_CTRL_AC;
221 }
222
223 static int mag3110_change_config(struct mag3110_data *data, u8 reg, u8 val)
224 {
225 int ret;
226 int is_active;
227
228 mutex_lock(&data->lock);
229
230 is_active = mag3110_is_active(data);
231 if (is_active < 0) {
232 ret = is_active;
233 goto fail;
234 }
235
236
237 if (is_active > 0) {
238 ret = mag3110_standby(data);
239 if (ret < 0)
240 goto fail;
241 }
242
243
244
245
246
247 ret = mag3110_wait_standby(data);
248 if (ret < 0)
249 goto fail;
250
251 ret = i2c_smbus_write_byte_data(data->client, reg, val);
252 if (ret < 0)
253 goto fail;
254
255 if (is_active > 0) {
256 ret = mag3110_active(data);
257 if (ret < 0)
258 goto fail;
259 }
260
261 ret = 0;
262 fail:
263 mutex_unlock(&data->lock);
264
265 return ret;
266 }
267
268 static int mag3110_read_raw(struct iio_dev *indio_dev,
269 struct iio_chan_spec const *chan,
270 int *val, int *val2, long mask)
271 {
272 struct mag3110_data *data = iio_priv(indio_dev);
273 __be16 buffer[3];
274 int i, ret;
275
276 switch (mask) {
277 case IIO_CHAN_INFO_RAW:
278 ret = iio_device_claim_direct_mode(indio_dev);
279 if (ret)
280 return ret;
281
282 switch (chan->type) {
283 case IIO_MAGN:
284 ret = mag3110_read(data, buffer);
285 if (ret < 0)
286 goto release;
287 *val = sign_extend32(
288 be16_to_cpu(buffer[chan->scan_index]), 15);
289 ret = IIO_VAL_INT;
290 break;
291 case IIO_TEMP:
292 mutex_lock(&data->lock);
293 ret = mag3110_request(data);
294 if (ret < 0) {
295 mutex_unlock(&data->lock);
296 goto release;
297 }
298 ret = i2c_smbus_read_byte_data(data->client,
299 MAG3110_DIE_TEMP);
300 mutex_unlock(&data->lock);
301 if (ret < 0)
302 goto release;
303 *val = sign_extend32(ret, 7);
304 ret = IIO_VAL_INT;
305 break;
306 default:
307 ret = -EINVAL;
308 }
309 release:
310 iio_device_release_direct_mode(indio_dev);
311 return ret;
312
313 case IIO_CHAN_INFO_SCALE:
314 switch (chan->type) {
315 case IIO_MAGN:
316 *val = 0;
317 *val2 = 1000;
318 return IIO_VAL_INT_PLUS_MICRO;
319 case IIO_TEMP:
320 *val = 1000;
321 return IIO_VAL_INT;
322 default:
323 return -EINVAL;
324 }
325 case IIO_CHAN_INFO_SAMP_FREQ:
326 i = data->ctrl_reg1 >> MAG3110_CTRL_DR_SHIFT;
327 *val = mag3110_samp_freq[i][0];
328 *val2 = mag3110_samp_freq[i][1];
329 return IIO_VAL_INT_PLUS_MICRO;
330 case IIO_CHAN_INFO_CALIBBIAS:
331 ret = i2c_smbus_read_word_swapped(data->client,
332 MAG3110_OFF_X + 2 * chan->scan_index);
333 if (ret < 0)
334 return ret;
335 *val = sign_extend32(ret >> 1, 14);
336 return IIO_VAL_INT;
337 }
338 return -EINVAL;
339 }
340
341 static int mag3110_write_raw(struct iio_dev *indio_dev,
342 struct iio_chan_spec const *chan,
343 int val, int val2, long mask)
344 {
345 struct mag3110_data *data = iio_priv(indio_dev);
346 int rate, ret;
347
348 ret = iio_device_claim_direct_mode(indio_dev);
349 if (ret)
350 return ret;
351
352 switch (mask) {
353 case IIO_CHAN_INFO_SAMP_FREQ:
354 rate = mag3110_get_samp_freq_index(data, val, val2);
355 if (rate < 0) {
356 ret = -EINVAL;
357 break;
358 }
359 data->ctrl_reg1 &= 0xff & ~MAG3110_CTRL_DR_MASK
360 & ~MAG3110_CTRL_AC;
361 data->ctrl_reg1 |= rate << MAG3110_CTRL_DR_SHIFT;
362 data->sleep_val = mag3110_calculate_sleep(data);
363 if (data->sleep_val < 40)
364 data->ctrl_reg1 |= MAG3110_CTRL_AC;
365
366 ret = mag3110_change_config(data, MAG3110_CTRL_REG1,
367 data->ctrl_reg1);
368 break;
369 case IIO_CHAN_INFO_CALIBBIAS:
370 if (val < -10000 || val > 10000) {
371 ret = -EINVAL;
372 break;
373 }
374 ret = i2c_smbus_write_word_swapped(data->client,
375 MAG3110_OFF_X + 2 * chan->scan_index, val << 1);
376 break;
377 default:
378 ret = -EINVAL;
379 break;
380 }
381 iio_device_release_direct_mode(indio_dev);
382 return ret;
383 }
384
385 static irqreturn_t mag3110_trigger_handler(int irq, void *p)
386 {
387 struct iio_poll_func *pf = p;
388 struct iio_dev *indio_dev = pf->indio_dev;
389 struct mag3110_data *data = iio_priv(indio_dev);
390 u8 buffer[16];
391 int ret;
392
393 ret = mag3110_read(data, (__be16 *) buffer);
394 if (ret < 0)
395 goto done;
396
397 if (test_bit(3, indio_dev->active_scan_mask)) {
398 ret = i2c_smbus_read_byte_data(data->client,
399 MAG3110_DIE_TEMP);
400 if (ret < 0)
401 goto done;
402 buffer[6] = ret;
403 }
404
405 iio_push_to_buffers_with_timestamp(indio_dev, buffer,
406 iio_get_time_ns(indio_dev));
407
408 done:
409 iio_trigger_notify_done(indio_dev->trig);
410 return IRQ_HANDLED;
411 }
412
413 #define MAG3110_CHANNEL(axis, idx) { \
414 .type = IIO_MAGN, \
415 .modified = 1, \
416 .channel2 = IIO_MOD_##axis, \
417 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
418 BIT(IIO_CHAN_INFO_CALIBBIAS), \
419 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
420 BIT(IIO_CHAN_INFO_SCALE), \
421 .scan_index = idx, \
422 .scan_type = { \
423 .sign = 's', \
424 .realbits = 16, \
425 .storagebits = 16, \
426 .endianness = IIO_BE, \
427 }, \
428 }
429
430 static const struct iio_chan_spec mag3110_channels[] = {
431 MAG3110_CHANNEL(X, 0),
432 MAG3110_CHANNEL(Y, 1),
433 MAG3110_CHANNEL(Z, 2),
434 {
435 .type = IIO_TEMP,
436 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
437 BIT(IIO_CHAN_INFO_SCALE),
438 .scan_index = 3,
439 .scan_type = {
440 .sign = 's',
441 .realbits = 8,
442 .storagebits = 8,
443 },
444 },
445 IIO_CHAN_SOFT_TIMESTAMP(4),
446 };
447
448 static struct attribute *mag3110_attributes[] = {
449 &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
450 NULL
451 };
452
453 static const struct attribute_group mag3110_group = {
454 .attrs = mag3110_attributes,
455 };
456
457 static const struct iio_info mag3110_info = {
458 .attrs = &mag3110_group,
459 .read_raw = &mag3110_read_raw,
460 .write_raw = &mag3110_write_raw,
461 };
462
463 static const unsigned long mag3110_scan_masks[] = {0x7, 0xf, 0};
464
465 static int mag3110_probe(struct i2c_client *client,
466 const struct i2c_device_id *id)
467 {
468 struct mag3110_data *data;
469 struct iio_dev *indio_dev;
470 int ret;
471
472 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
473 if (!indio_dev)
474 return -ENOMEM;
475
476 data = iio_priv(indio_dev);
477
478 data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
479 if (IS_ERR(data->vdd_reg)) {
480 if (PTR_ERR(data->vdd_reg) == -EPROBE_DEFER)
481 return -EPROBE_DEFER;
482
483 dev_err(&client->dev, "failed to get VDD regulator!\n");
484 return PTR_ERR(data->vdd_reg);
485 }
486
487 data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
488 if (IS_ERR(data->vddio_reg)) {
489 if (PTR_ERR(data->vddio_reg) == -EPROBE_DEFER)
490 return -EPROBE_DEFER;
491
492 dev_err(&client->dev, "failed to get VDDIO regulator!\n");
493 return PTR_ERR(data->vddio_reg);
494 }
495
496 ret = regulator_enable(data->vdd_reg);
497 if (ret) {
498 dev_err(&client->dev, "failed to enable VDD regulator!\n");
499 return ret;
500 }
501
502 ret = regulator_enable(data->vddio_reg);
503 if (ret) {
504 dev_err(&client->dev, "failed to enable VDDIO regulator!\n");
505 goto disable_regulator_vdd;
506 }
507
508 ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
509 if (ret < 0)
510 goto disable_regulators;
511 if (ret != MAG3110_DEVICE_ID) {
512 ret = -ENODEV;
513 goto disable_regulators;
514 }
515
516 data->client = client;
517 mutex_init(&data->lock);
518
519 i2c_set_clientdata(client, indio_dev);
520 indio_dev->info = &mag3110_info;
521 indio_dev->name = id->name;
522 indio_dev->dev.parent = &client->dev;
523 indio_dev->modes = INDIO_DIRECT_MODE;
524 indio_dev->channels = mag3110_channels;
525 indio_dev->num_channels = ARRAY_SIZE(mag3110_channels);
526 indio_dev->available_scan_masks = mag3110_scan_masks;
527
528 data->ctrl_reg1 = MAG3110_CTRL_DR_DEFAULT << MAG3110_CTRL_DR_SHIFT;
529 data->sleep_val = mag3110_calculate_sleep(data);
530 if (data->sleep_val < 40)
531 data->ctrl_reg1 |= MAG3110_CTRL_AC;
532
533 ret = mag3110_change_config(data, MAG3110_CTRL_REG1, data->ctrl_reg1);
534 if (ret < 0)
535 goto disable_regulators;
536
537 ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG2,
538 MAG3110_CTRL_AUTO_MRST_EN);
539 if (ret < 0)
540 goto standby_on_error;
541
542 ret = iio_triggered_buffer_setup(indio_dev, NULL,
543 mag3110_trigger_handler, NULL);
544 if (ret < 0)
545 goto standby_on_error;
546
547 ret = iio_device_register(indio_dev);
548 if (ret < 0)
549 goto buffer_cleanup;
550 return 0;
551
552 buffer_cleanup:
553 iio_triggered_buffer_cleanup(indio_dev);
554 standby_on_error:
555 mag3110_standby(iio_priv(indio_dev));
556 disable_regulators:
557 regulator_disable(data->vddio_reg);
558 disable_regulator_vdd:
559 regulator_disable(data->vdd_reg);
560
561 return ret;
562 }
563
564 static int mag3110_remove(struct i2c_client *client)
565 {
566 struct iio_dev *indio_dev = i2c_get_clientdata(client);
567 struct mag3110_data *data = iio_priv(indio_dev);
568
569 iio_device_unregister(indio_dev);
570 iio_triggered_buffer_cleanup(indio_dev);
571 mag3110_standby(iio_priv(indio_dev));
572 regulator_disable(data->vddio_reg);
573 regulator_disable(data->vdd_reg);
574
575 return 0;
576 }
577
578 #ifdef CONFIG_PM_SLEEP
579 static int mag3110_suspend(struct device *dev)
580 {
581 struct mag3110_data *data = iio_priv(i2c_get_clientdata(
582 to_i2c_client(dev)));
583 int ret;
584
585 ret = mag3110_standby(iio_priv(i2c_get_clientdata(
586 to_i2c_client(dev))));
587 if (ret)
588 return ret;
589
590 ret = regulator_disable(data->vddio_reg);
591 if (ret) {
592 dev_err(dev, "failed to disable VDDIO regulator\n");
593 return ret;
594 }
595
596 ret = regulator_disable(data->vdd_reg);
597 if (ret) {
598 dev_err(dev, "failed to disable VDD regulator\n");
599 return ret;
600 }
601
602 return 0;
603 }
604
605 static int mag3110_resume(struct device *dev)
606 {
607 struct mag3110_data *data = iio_priv(i2c_get_clientdata(
608 to_i2c_client(dev)));
609 int ret;
610
611 ret = regulator_enable(data->vdd_reg);
612 if (ret) {
613 dev_err(dev, "failed to enable VDD regulator\n");
614 return ret;
615 }
616
617 ret = regulator_enable(data->vddio_reg);
618 if (ret) {
619 dev_err(dev, "failed to enable VDDIO regulator\n");
620 regulator_disable(data->vdd_reg);
621 return ret;
622 }
623
624 return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
625 data->ctrl_reg1);
626 }
627
628 static SIMPLE_DEV_PM_OPS(mag3110_pm_ops, mag3110_suspend, mag3110_resume);
629 #define MAG3110_PM_OPS (&mag3110_pm_ops)
630 #else
631 #define MAG3110_PM_OPS NULL
632 #endif
633
634 static const struct i2c_device_id mag3110_id[] = {
635 { "mag3110", 0 },
636 { }
637 };
638 MODULE_DEVICE_TABLE(i2c, mag3110_id);
639
640 static const struct of_device_id mag3110_of_match[] = {
641 { .compatible = "fsl,mag3110" },
642 { }
643 };
644 MODULE_DEVICE_TABLE(of, mag3110_of_match);
645
646 static struct i2c_driver mag3110_driver = {
647 .driver = {
648 .name = "mag3110",
649 .of_match_table = mag3110_of_match,
650 .pm = MAG3110_PM_OPS,
651 },
652 .probe = mag3110_probe,
653 .remove = mag3110_remove,
654 .id_table = mag3110_id,
655 };
656 module_i2c_driver(mag3110_driver);
657
658 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
659 MODULE_DESCRIPTION("Freescale MAG3110 magnetometer driver");
660 MODULE_LICENSE("GPL");