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adis16240_core.c
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1 /*
2  * ADIS16240 Programmable Impact Sensor and Recorder driver
3  *
4  * Copyright 2010 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/gpio.h>
12 #include <linux/delay.h>
13 #include <linux/mutex.h>
14 #include <linux/device.h>
15 #include <linux/kernel.h>
16 #include <linux/spi/spi.h>
17 #include <linux/slab.h>
18 #include <linux/sysfs.h>
19 #include <linux/list.h>
20 #include <linux/module.h>
21 
22 #include <linux/iio/iio.h>
23 #include <linux/iio/sysfs.h>
24 #include <linux/iio/buffer.h>
25 
26 #include "adis16240.h"
27 
28 #define DRIVER_NAME "adis16240"
29 
30 static int adis16240_check_status(struct iio_dev *indio_dev);
31 
38 static int adis16240_spi_write_reg_8(struct iio_dev *indio_dev,
39  u8 reg_address,
40  u8 val)
41 {
42  int ret;
43  struct adis16240_state *st = iio_priv(indio_dev);
44 
45  mutex_lock(&st->buf_lock);
46  st->tx[0] = ADIS16240_WRITE_REG(reg_address);
47  st->tx[1] = val;
48 
49  ret = spi_write(st->us, st->tx, 2);
50  mutex_unlock(&st->buf_lock);
51 
52  return ret;
53 }
54 
62 static int adis16240_spi_write_reg_16(struct iio_dev *indio_dev,
63  u8 lower_reg_address,
64  u16 value)
65 {
66  int ret;
67  struct spi_message msg;
68  struct adis16240_state *st = iio_priv(indio_dev);
69  struct spi_transfer xfers[] = {
70  {
71  .tx_buf = st->tx,
72  .bits_per_word = 8,
73  .len = 2,
74  .cs_change = 1,
75  .delay_usecs = 35,
76  }, {
77  .tx_buf = st->tx + 2,
78  .bits_per_word = 8,
79  .len = 2,
80  .delay_usecs = 35,
81  },
82  };
83 
84  mutex_lock(&st->buf_lock);
85  st->tx[0] = ADIS16240_WRITE_REG(lower_reg_address);
86  st->tx[1] = value & 0xFF;
87  st->tx[2] = ADIS16240_WRITE_REG(lower_reg_address + 1);
88  st->tx[3] = (value >> 8) & 0xFF;
89 
90  spi_message_init(&msg);
91  spi_message_add_tail(&xfers[0], &msg);
92  spi_message_add_tail(&xfers[1], &msg);
93  ret = spi_sync(st->us, &msg);
94  mutex_unlock(&st->buf_lock);
95 
96  return ret;
97 }
98 
106 static int adis16240_spi_read_reg_16(struct iio_dev *indio_dev,
107  u8 lower_reg_address,
108  u16 *val)
109 {
110  struct spi_message msg;
111  struct adis16240_state *st = iio_priv(indio_dev);
112  int ret;
113  struct spi_transfer xfers[] = {
114  {
115  .tx_buf = st->tx,
116  .bits_per_word = 8,
117  .len = 2,
118  .cs_change = 1,
119  .delay_usecs = 35,
120  }, {
121  .rx_buf = st->rx,
122  .bits_per_word = 8,
123  .len = 2,
124  .cs_change = 1,
125  .delay_usecs = 35,
126  },
127  };
128 
129  mutex_lock(&st->buf_lock);
130  st->tx[0] = ADIS16240_READ_REG(lower_reg_address);
131  st->tx[1] = 0;
132  st->tx[2] = 0;
133  st->tx[3] = 0;
134 
135  spi_message_init(&msg);
136  spi_message_add_tail(&xfers[0], &msg);
137  spi_message_add_tail(&xfers[1], &msg);
138  ret = spi_sync(st->us, &msg);
139  if (ret) {
140  dev_err(&st->us->dev,
141  "problem when reading 16 bit register 0x%02X",
142  lower_reg_address);
143  goto error_ret;
144  }
145  *val = (st->rx[0] << 8) | st->rx[1];
146 
147 error_ret:
148  mutex_unlock(&st->buf_lock);
149  return ret;
150 }
151 
152 static ssize_t adis16240_spi_read_signed(struct device *dev,
153  struct device_attribute *attr,
154  char *buf,
155  unsigned bits)
156 {
157  struct iio_dev *indio_dev = dev_to_iio_dev(dev);
158  int ret;
159  s16 val = 0;
160  unsigned shift = 16 - bits;
161  struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
162 
163  ret = adis16240_spi_read_reg_16(indio_dev,
164  this_attr->address, (u16 *)&val);
165  if (ret)
166  return ret;
167 
168  if (val & ADIS16240_ERROR_ACTIVE)
169  adis16240_check_status(indio_dev);
170 
171  val = ((s16)(val << shift) >> shift);
172  return sprintf(buf, "%d\n", val);
173 }
174 
175 static ssize_t adis16240_read_12bit_signed(struct device *dev,
176  struct device_attribute *attr,
177  char *buf)
178 {
179  ssize_t ret;
180  struct iio_dev *indio_dev = dev_to_iio_dev(dev);
181 
182  /* Take the iio_dev status lock */
183  mutex_lock(&indio_dev->mlock);
184  ret = adis16240_spi_read_signed(dev, attr, buf, 12);
185  mutex_unlock(&indio_dev->mlock);
186 
187  return ret;
188 }
189 
190 static int adis16240_reset(struct iio_dev *indio_dev)
191 {
192  int ret;
193  ret = adis16240_spi_write_reg_8(indio_dev,
194  ADIS16240_GLOB_CMD,
195  ADIS16240_GLOB_CMD_SW_RESET);
196  if (ret)
197  dev_err(&indio_dev->dev, "problem resetting device");
198 
199  return ret;
200 }
201 
202 int adis16240_set_irq(struct iio_dev *indio_dev, bool enable)
203 {
204  int ret = 0;
205  u16 msc;
206 
207  ret = adis16240_spi_read_reg_16(indio_dev,
208  ADIS16240_MSC_CTRL, &msc);
209  if (ret)
210  goto error_ret;
211 
212  msc |= ADIS16240_MSC_CTRL_ACTIVE_HIGH;
213  msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_DIO2;
214  if (enable)
215  msc |= ADIS16240_MSC_CTRL_DATA_RDY_EN;
216  else
217  msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_EN;
218 
219  ret = adis16240_spi_write_reg_16(indio_dev,
220  ADIS16240_MSC_CTRL, msc);
221 
222 error_ret:
223  return ret;
224 }
225 
226 static int adis16240_self_test(struct iio_dev *indio_dev)
227 {
228  int ret;
229  ret = adis16240_spi_write_reg_16(indio_dev,
230  ADIS16240_MSC_CTRL,
231  ADIS16240_MSC_CTRL_SELF_TEST_EN);
232  if (ret) {
233  dev_err(&indio_dev->dev, "problem starting self test");
234  goto err_ret;
235  }
236 
237  msleep(ADIS16240_STARTUP_DELAY);
238 
239  adis16240_check_status(indio_dev);
240 
241 err_ret:
242  return ret;
243 }
244 
245 static int adis16240_check_status(struct iio_dev *indio_dev)
246 {
247  u16 status;
248  int ret;
249  struct device *dev = &indio_dev->dev;
250 
251  ret = adis16240_spi_read_reg_16(indio_dev,
252  ADIS16240_DIAG_STAT, &status);
253 
254  if (ret < 0) {
255  dev_err(dev, "Reading status failed\n");
256  goto error_ret;
257  }
258 
259  ret = status & 0x2F;
260  if (status & ADIS16240_DIAG_STAT_PWRON_FAIL)
261  dev_err(dev, "Power-on, self-test fail\n");
262  if (status & ADIS16240_DIAG_STAT_SPI_FAIL)
263  dev_err(dev, "SPI failure\n");
264  if (status & ADIS16240_DIAG_STAT_FLASH_UPT)
265  dev_err(dev, "Flash update failed\n");
266  if (status & ADIS16240_DIAG_STAT_POWER_HIGH)
267  dev_err(dev, "Power supply above 3.625V\n");
268  if (status & ADIS16240_DIAG_STAT_POWER_LOW)
269  dev_err(dev, "Power supply below 2.225V\n");
270 
271 error_ret:
272  return ret;
273 }
274 
275 static int adis16240_initial_setup(struct iio_dev *indio_dev)
276 {
277  int ret;
278  struct device *dev = &indio_dev->dev;
279 
280  /* Disable IRQ */
281  ret = adis16240_set_irq(indio_dev, false);
282  if (ret) {
283  dev_err(dev, "disable irq failed");
284  goto err_ret;
285  }
286 
287  /* Do self test */
288  ret = adis16240_self_test(indio_dev);
289  if (ret) {
290  dev_err(dev, "self test failure");
291  goto err_ret;
292  }
293 
294  /* Read status register to check the result */
295  ret = adis16240_check_status(indio_dev);
296  if (ret) {
297  adis16240_reset(indio_dev);
298  dev_err(dev, "device not playing ball -> reset");
299  msleep(ADIS16240_STARTUP_DELAY);
300  ret = adis16240_check_status(indio_dev);
301  if (ret) {
302  dev_err(dev, "giving up");
303  goto err_ret;
304  }
305  }
306 
307 err_ret:
308  return ret;
309 }
310 
311 static IIO_DEVICE_ATTR(in_accel_xyz_squared_peak_raw, S_IRUGO,
312  adis16240_read_12bit_signed, NULL,
313  ADIS16240_XYZPEAK_OUT);
314 
315 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("4096");
316 
317 enum adis16240_chan {
318  in_supply,
319  in_aux,
320  accel_x,
321  accel_y,
322  accel_z,
323  temp,
324 };
325 
326 static const u8 adis16240_addresses[6][3] = {
327  [in_supply] = { ADIS16240_SUPPLY_OUT },
328  [in_aux] = { ADIS16240_AUX_ADC },
329  [accel_x] = { ADIS16240_XACCL_OUT, ADIS16240_XACCL_OFF,
330  ADIS16240_XPEAK_OUT },
331  [accel_y] = { ADIS16240_YACCL_OUT, ADIS16240_YACCL_OFF,
332  ADIS16240_YPEAK_OUT },
333  [accel_z] = { ADIS16240_ZACCL_OUT, ADIS16240_ZACCL_OFF,
334  ADIS16240_ZPEAK_OUT },
335  [temp] = { ADIS16240_TEMP_OUT },
336 };
337 
338 static int adis16240_read_raw(struct iio_dev *indio_dev,
339  struct iio_chan_spec const *chan,
340  int *val, int *val2,
341  long mask)
342 {
343  int ret;
344  int bits;
345  u8 addr;
346  s16 val16;
347 
348  switch (mask) {
349  case IIO_CHAN_INFO_RAW:
350  mutex_lock(&indio_dev->mlock);
351  addr = adis16240_addresses[chan->address][0];
352  ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
353  if (ret) {
354  mutex_unlock(&indio_dev->mlock);
355  return ret;
356  }
357 
358  if (val16 & ADIS16240_ERROR_ACTIVE) {
359  ret = adis16240_check_status(indio_dev);
360  if (ret) {
361  mutex_unlock(&indio_dev->mlock);
362  return ret;
363  }
364  }
365  val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
366  if (chan->scan_type.sign == 's')
367  val16 = (s16)(val16 <<
368  (16 - chan->scan_type.realbits)) >>
369  (16 - chan->scan_type.realbits);
370  *val = val16;
371  mutex_unlock(&indio_dev->mlock);
372  return IIO_VAL_INT;
373  case IIO_CHAN_INFO_SCALE:
374  switch (chan->type) {
375  case IIO_VOLTAGE:
376  if (chan->channel == 0) {
377  *val = 4;
378  *val2 = 880000; /* 4.88 mV */
379  return IIO_VAL_INT_PLUS_MICRO;
380  } else {
381  return -EINVAL;
382  }
383  case IIO_TEMP:
384  *val = 244; /* 0.244 C */
385  *val2 = 0;
386  return IIO_VAL_INT_PLUS_MICRO;
387  case IIO_ACCEL:
388  *val = 0;
389  *val2 = IIO_G_TO_M_S_2(51400); /* 51.4 mg */
390  return IIO_VAL_INT_PLUS_MICRO;
391  default:
392  return -EINVAL;
393  }
394  break;
395  case IIO_CHAN_INFO_PEAK_SCALE:
396  *val = 0;
397  *val2 = IIO_G_TO_M_S_2(51400); /* 51.4 mg */
398  return IIO_VAL_INT_PLUS_MICRO;
399  case IIO_CHAN_INFO_OFFSET:
400  *val = 25000 / 244 - 0x133; /* 25 C = 0x133 */
401  return IIO_VAL_INT;
402  case IIO_CHAN_INFO_CALIBBIAS:
403  bits = 10;
404  mutex_lock(&indio_dev->mlock);
405  addr = adis16240_addresses[chan->address][1];
406  ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
407  if (ret) {
408  mutex_unlock(&indio_dev->mlock);
409  return ret;
410  }
411  val16 &= (1 << bits) - 1;
412  val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
413  *val = val16;
414  mutex_unlock(&indio_dev->mlock);
415  return IIO_VAL_INT;
416  case IIO_CHAN_INFO_PEAK:
417  bits = 10;
418  mutex_lock(&indio_dev->mlock);
419  addr = adis16240_addresses[chan->address][2];
420  ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
421  if (ret) {
422  mutex_unlock(&indio_dev->mlock);
423  return ret;
424  }
425  val16 &= (1 << bits) - 1;
426  val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
427  *val = val16;
428  mutex_unlock(&indio_dev->mlock);
429  return IIO_VAL_INT;
430  }
431  return -EINVAL;
432 }
433 
434 static int adis16240_write_raw(struct iio_dev *indio_dev,
435  struct iio_chan_spec const *chan,
436  int val,
437  int val2,
438  long mask)
439 {
440  int bits = 10;
441  s16 val16;
442  u8 addr;
443  switch (mask) {
444  case IIO_CHAN_INFO_CALIBBIAS:
445  val16 = val & ((1 << bits) - 1);
446  addr = adis16240_addresses[chan->address][1];
447  return adis16240_spi_write_reg_16(indio_dev, addr, val16);
448  }
449  return -EINVAL;
450 }
451 
452 static const struct iio_chan_spec adis16240_channels[] = {
453  {
454  .type = IIO_VOLTAGE,
455  .indexed = 1,
456  .channel = 0,
457  .extend_name = "supply",
458  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
459  IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
460  .address = in_supply,
461  .scan_index = ADIS16240_SCAN_SUPPLY,
462  .scan_type = {
463  .sign = 'u',
464  .realbits = 10,
465  .storagebits = 16,
466  },
467  }, {
468  .type = IIO_VOLTAGE,
469  .indexed = 1,
470  .channel = 1,
471  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT,
472  .address = in_aux,
473  .scan_index = ADIS16240_SCAN_AUX_ADC,
474  .scan_type = {
475  .sign = 'u',
476  .realbits = 10,
477  .storagebits = 16,
478  },
479  }, {
480  .type = IIO_ACCEL,
481  .modified = 1,
482  .channel2 = IIO_MOD_X,
483  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
484  IIO_CHAN_INFO_SCALE_SHARED_BIT |
485  IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
486  IIO_CHAN_INFO_PEAK_SEPARATE_BIT,
487  .address = accel_x,
488  .scan_index = ADIS16240_SCAN_ACC_X,
489  .scan_type = {
490  .sign = 's',
491  .realbits = 10,
492  .storagebits = 16,
493  },
494  }, {
495  .type = IIO_ACCEL,
496  .modified = 1,
497  .channel2 = IIO_MOD_Y,
498  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
499  IIO_CHAN_INFO_SCALE_SHARED_BIT |
500  IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
501  IIO_CHAN_INFO_PEAK_SEPARATE_BIT,
502  .address = accel_y,
503  .scan_index = ADIS16240_SCAN_ACC_Y,
504  .scan_type = {
505  .sign = 's',
506  .realbits = 10,
507  .storagebits = 16,
508  },
509  }, {
510  .type = IIO_ACCEL,
511  .modified = 1,
512  .channel2 = IIO_MOD_Z,
513  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
514  IIO_CHAN_INFO_SCALE_SHARED_BIT |
515  IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
516  IIO_CHAN_INFO_PEAK_SEPARATE_BIT,
517  .address = accel_z,
518  .scan_index = ADIS16240_SCAN_ACC_Z,
519  .scan_type = {
520  .sign = 's',
521  .realbits = 10,
522  .storagebits = 16,
523  },
524  }, {
525  .type = IIO_TEMP,
526  .indexed = 1,
527  .channel = 0,
528  .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
529  IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
530  .address = temp,
531  .scan_index = ADIS16240_SCAN_TEMP,
532  .scan_type = {
533  .sign = 'u',
534  .realbits = 10,
535  .storagebits = 16,
536  },
537  },
538  IIO_CHAN_SOFT_TIMESTAMP(6)
539 };
540 
541 static struct attribute *adis16240_attributes[] = {
542  &iio_dev_attr_in_accel_xyz_squared_peak_raw.dev_attr.attr,
543  &iio_const_attr_sampling_frequency_available.dev_attr.attr,
544  NULL
545 };
546 
547 static const struct attribute_group adis16240_attribute_group = {
548  .attrs = adis16240_attributes,
549 };
550 
551 static const struct iio_info adis16240_info = {
552  .attrs = &adis16240_attribute_group,
553  .read_raw = &adis16240_read_raw,
554  .write_raw = &adis16240_write_raw,
555  .driver_module = THIS_MODULE,
556 };
557 
558 static int __devinit adis16240_probe(struct spi_device *spi)
559 {
560  int ret;
561  struct adis16240_state *st;
562  struct iio_dev *indio_dev;
563 
564  /* setup the industrialio driver allocated elements */
565  indio_dev = iio_device_alloc(sizeof(*st));
566  if (indio_dev == NULL) {
567  ret = -ENOMEM;
568  goto error_ret;
569  }
570  st = iio_priv(indio_dev);
571  /* this is only used for removal purposes */
572  spi_set_drvdata(spi, indio_dev);
573 
574  st->us = spi;
575  mutex_init(&st->buf_lock);
576 
577  indio_dev->name = spi->dev.driver->name;
578  indio_dev->dev.parent = &spi->dev;
579  indio_dev->info = &adis16240_info;
580  indio_dev->channels = adis16240_channels;
581  indio_dev->num_channels = ARRAY_SIZE(adis16240_channels);
582  indio_dev->modes = INDIO_DIRECT_MODE;
583 
584  ret = adis16240_configure_ring(indio_dev);
585  if (ret)
586  goto error_free_dev;
587 
588  ret = iio_buffer_register(indio_dev,
589  adis16240_channels,
590  ARRAY_SIZE(adis16240_channels));
591  if (ret) {
592  printk(KERN_ERR "failed to initialize the ring\n");
593  goto error_unreg_ring_funcs;
594  }
595 
596  if (spi->irq) {
597  ret = adis16240_probe_trigger(indio_dev);
598  if (ret)
599  goto error_uninitialize_ring;
600  }
601 
602  /* Get the device into a sane initial state */
603  ret = adis16240_initial_setup(indio_dev);
604  if (ret)
605  goto error_remove_trigger;
606  ret = iio_device_register(indio_dev);
607  if (ret)
608  goto error_remove_trigger;
609  return 0;
610 
611 error_remove_trigger:
612  adis16240_remove_trigger(indio_dev);
613 error_uninitialize_ring:
614  iio_buffer_unregister(indio_dev);
615 error_unreg_ring_funcs:
616  adis16240_unconfigure_ring(indio_dev);
617 error_free_dev:
618  iio_device_free(indio_dev);
619 error_ret:
620  return ret;
621 }
622 
623 static int __devexit adis16240_remove(struct spi_device *spi)
624 {
625 
626  struct iio_dev *indio_dev = spi_get_drvdata(spi);
627 
628  iio_device_unregister(indio_dev);
629  adis16240_remove_trigger(indio_dev);
630  iio_buffer_unregister(indio_dev);
631  adis16240_unconfigure_ring(indio_dev);
632  iio_device_free(indio_dev);
633 
634  return 0;
635 }
636 
637 static struct spi_driver adis16240_driver = {
638  .driver = {
639  .name = "adis16240",
640  .owner = THIS_MODULE,
641  },
642  .probe = adis16240_probe,
643  .remove = __devexit_p(adis16240_remove),
644 };
645 module_spi_driver(adis16240_driver);
646 
647 MODULE_AUTHOR("Barry Song <[email protected]>");
648 MODULE_DESCRIPTION("Analog Devices Programmable Impact Sensor and Recorder");
649 MODULE_LICENSE("GPL v2");
650 MODULE_ALIAS("spi:adis16240");
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