drivers/staging/iio/accel/adis16240_core.c

   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
  21 #include "../iio.h"
  22 #include "../sysfs.h"
  23 #include "../ring_generic.h"
  24 #include "accel.h"
  25 #include "../adc/adc.h"
  26
  27 #include "adis16240.h"
  28
  29 #define DRIVER_NAME             "adis16240"
  30
  31 static int adis16240_check_status(struct iio_dev *indio_dev);
  32
  33 /**
  34  * adis16240_spi_write_reg_8() - write single byte to a register
  35  * @indio_dev: iio_dev associated with device
  36  * @reg_address: the address of the register to be written
  37  * @val: the value to write
  38  **/
  39 static int adis16240_spi_write_reg_8(struct iio_dev *indio_dev,
  40                                      u8 reg_address,
  41                                      u8 val)
  42 {
  43         int ret;
  44         struct adis16240_state *st = iio_priv(indio_dev);
  45
  46         mutex_lock(&st->buf_lock);
  47         st->tx[0] = ADIS16240_WRITE_REG(reg_address);
  48         st->tx[1] = val;
  49
  50         ret = spi_write(st->us, st->tx, 2);
  51         mutex_unlock(&st->buf_lock);
  52
  53         return ret;
  54 }
  55
  56 /**
  57  * adis16240_spi_write_reg_16() - write 2 bytes to a pair of registers
  58  * @indio_dev: iio_dev for this device
  59  * @reg_address: the address of the lower of the two registers. Second register
  60  *               is assumed to have address one greater.
  61  * @val: value to be written
  62  **/
  63 static int adis16240_spi_write_reg_16(struct iio_dev *indio_dev,
  64                                       u8 lower_reg_address,
  65                                       u16 value)
  66 {
  67         int ret;
  68         struct spi_message msg;
  69         struct adis16240_state *st = iio_priv(indio_dev);
  70         struct spi_transfer xfers[] = {
  71                 {
  72                         .tx_buf = st->tx,
  73                         .bits_per_word = 8,
  74                         .len = 2,
  75                         .cs_change = 1,
  76                         .delay_usecs = 35,
  77                 }, {
  78                         .tx_buf = st->tx + 2,
  79                         .bits_per_word = 8,
  80                         .len = 2,
  81                         .delay_usecs = 35,
  82                 },
  83         };
  84
  85         mutex_lock(&st->buf_lock);
  86         st->tx[0] = ADIS16240_WRITE_REG(lower_reg_address);
  87         st->tx[1] = value & 0xFF;
  88         st->tx[2] = ADIS16240_WRITE_REG(lower_reg_address + 1);
  89         st->tx[3] = (value >> 8) & 0xFF;
  90
  91         spi_message_init(&msg);
  92         spi_message_add_tail(&xfers[0], &msg);
  93         spi_message_add_tail(&xfers[1], &msg);
  94         ret = spi_sync(st->us, &msg);
  95         mutex_unlock(&st->buf_lock);
  96
  97         return ret;
  98 }
  99
 100 /**
 101  * adis16240_spi_read_reg_16() - read 2 bytes from a 16-bit register
 102  * @indio_dev: iio_dev for this device
 103  * @reg_address: the address of the lower of the two registers. Second register
 104  *               is assumed to have address one greater.
 105  * @val: somewhere to pass back the value read
 106  **/
 107 static int adis16240_spi_read_reg_16(struct iio_dev *indio_dev,
 108                 u8 lower_reg_address,
 109                 u16 *val)
 110 {
 111         struct spi_message msg;
 112         struct adis16240_state *st = iio_priv(indio_dev);
 113         int ret;
 114         struct spi_transfer xfers[] = {
 115                 {
 116                         .tx_buf = st->tx,
 117                         .bits_per_word = 8,
 118                         .len = 2,
 119                         .cs_change = 1,
 120                         .delay_usecs = 35,
 121                 }, {
 122                         .rx_buf = st->rx,
 123                         .bits_per_word = 8,
 124                         .len = 2,
 125                         .cs_change = 1,
 126                         .delay_usecs = 35,
 127                 },
 128         };
 129
 130         mutex_lock(&st->buf_lock);
 131         st->tx[0] = ADIS16240_READ_REG(lower_reg_address);
 132         st->tx[1] = 0;
 133         st->tx[2] = 0;
 134         st->tx[3] = 0;
 135
 136         spi_message_init(&msg);
 137         spi_message_add_tail(&xfers[0], &msg);
 138         spi_message_add_tail(&xfers[1], &msg);
 139         ret = spi_sync(st->us, &msg);
 140         if (ret) {
 141                 dev_err(&st->us->dev,
 142                         "problem when reading 16 bit register 0x%02X",
 143                         lower_reg_address);
 144                 goto error_ret;
 145         }
 146         *val = (st->rx[0] << 8) | st->rx[1];
 147
 148 error_ret:
 149         mutex_unlock(&st->buf_lock);
 150         return ret;
 151 }
 152
 153 static ssize_t adis16240_spi_read_signed(struct device *dev,
 154                 struct device_attribute *attr,
 155                 char *buf,
 156                 unsigned bits)
 157 {
 158         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 159         int ret;
 160         s16 val = 0;
 161         unsigned shift = 16 - bits;
 162         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 163
 164         ret = adis16240_spi_read_reg_16(indio_dev,
 165                                         this_attr->address, (u16 *)&val);
 166         if (ret)
 167                 return ret;
 168
 169         if (val & ADIS16240_ERROR_ACTIVE)
 170                 adis16240_check_status(indio_dev);
 171
 172         val = ((s16)(val << shift) >> shift);
 173         return sprintf(buf, "%d\n", val);
 174 }
 175
 176 static ssize_t adis16240_read_12bit_signed(struct device *dev,
 177                 struct device_attribute *attr,
 178                 char *buf)
 179 {
 180         ssize_t ret;
 181         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 182
 183         /* Take the iio_dev status lock */
 184         mutex_lock(&indio_dev->mlock);
 185         ret =  adis16240_spi_read_signed(dev, attr, buf, 12);
 186         mutex_unlock(&indio_dev->mlock);
 187
 188         return ret;
 189 }
 190
 191 static int adis16240_reset(struct iio_dev *indio_dev)
 192 {
 193         int ret;
 194         ret = adis16240_spi_write_reg_8(indio_dev,
 195                         ADIS16240_GLOB_CMD,
 196                         ADIS16240_GLOB_CMD_SW_RESET);
 197         if (ret)
 198                 dev_err(&indio_dev->dev, "problem resetting device");
 199
 200         return ret;
 201 }
 202
 203 static ssize_t adis16240_write_reset(struct device *dev,
 204                 struct device_attribute *attr,
 205                 const char *buf, size_t len)
 206 {
 207         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 208
 209         if (len < 1)
 210                 return -EINVAL;
 211         switch (buf[0]) {
 212         case '1':
 213         case 'y':
 214         case 'Y':
 215                 return adis16240_reset(indio_dev);
 216         }
 217         return -EINVAL;
 218 }
 219
 220 int adis16240_set_irq(struct iio_dev *indio_dev, bool enable)
 221 {
 222         int ret = 0;
 223         u16 msc;
 224
 225         ret = adis16240_spi_read_reg_16(indio_dev,
 226                                         ADIS16240_MSC_CTRL, &msc);
 227         if (ret)
 228                 goto error_ret;
 229
 230         msc |= ADIS16240_MSC_CTRL_ACTIVE_HIGH;
 231         msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_DIO2;
 232         if (enable)
 233                 msc |= ADIS16240_MSC_CTRL_DATA_RDY_EN;
 234         else
 235                 msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_EN;
 236
 237         ret = adis16240_spi_write_reg_16(indio_dev,
 238                                          ADIS16240_MSC_CTRL, msc);
 239
 240 error_ret:
 241         return ret;
 242 }
 243
 244 static int adis16240_self_test(struct iio_dev *indio_dev)
 245 {
 246         int ret;
 247         ret = adis16240_spi_write_reg_16(indio_dev,
 248                         ADIS16240_MSC_CTRL,
 249                         ADIS16240_MSC_CTRL_SELF_TEST_EN);
 250         if (ret) {
 251                 dev_err(&indio_dev->dev, "problem starting self test");
 252                 goto err_ret;
 253         }
 254
 255         msleep(ADIS16240_STARTUP_DELAY);
 256
 257         adis16240_check_status(indio_dev);
 258
 259 err_ret:
 260         return ret;
 261 }
 262
 263 static int adis16240_check_status(struct iio_dev *indio_dev)
 264 {
 265         u16 status;
 266         int ret;
 267         struct device *dev = &indio_dev->dev;
 268
 269         ret = adis16240_spi_read_reg_16(indio_dev,
 270                                         ADIS16240_DIAG_STAT, &status);
 271
 272         if (ret < 0) {
 273                 dev_err(dev, "Reading status failed\n");
 274                 goto error_ret;
 275         }
 276
 277         ret = status & 0x2F;
 278         if (status & ADIS16240_DIAG_STAT_PWRON_FAIL)
 279                 dev_err(dev, "Power-on, self-test fail\n");
 280         if (status & ADIS16240_DIAG_STAT_SPI_FAIL)
 281                 dev_err(dev, "SPI failure\n");
 282         if (status & ADIS16240_DIAG_STAT_FLASH_UPT)
 283                 dev_err(dev, "Flash update failed\n");
 284         if (status & ADIS16240_DIAG_STAT_POWER_HIGH)
 285                 dev_err(dev, "Power supply above 3.625V\n");
 286         if (status & ADIS16240_DIAG_STAT_POWER_LOW)
 287                 dev_err(dev, "Power supply below 2.225V\n");
 288
 289 error_ret:
 290         return ret;
 291 }
 292
 293 static int adis16240_initial_setup(struct iio_dev *indio_dev)
 294 {
 295         int ret;
 296         struct device *dev = &indio_dev->dev;
 297
 298         /* Disable IRQ */
 299         ret = adis16240_set_irq(indio_dev, false);
 300         if (ret) {
 301                 dev_err(dev, "disable irq failed");
 302                 goto err_ret;
 303         }
 304
 305         /* Do self test */
 306         ret = adis16240_self_test(indio_dev);
 307         if (ret) {
 308                 dev_err(dev, "self test failure");
 309                 goto err_ret;
 310         }
 311
 312         /* Read status register to check the result */
 313         ret = adis16240_check_status(indio_dev);
 314         if (ret) {
 315                 adis16240_reset(indio_dev);
 316                 dev_err(dev, "device not playing ball -> reset");
 317                 msleep(ADIS16240_STARTUP_DELAY);
 318                 ret = adis16240_check_status(indio_dev);
 319                 if (ret) {
 320                         dev_err(dev, "giving up");
 321                         goto err_ret;
 322                 }
 323         }
 324
 325 err_ret:
 326         return ret;
 327 }
 328
 329 static IIO_DEVICE_ATTR(accel_xyz_squared_peak_raw, S_IRUGO,
 330                        adis16240_read_12bit_signed, NULL,
 331                        ADIS16240_XYZPEAK_OUT);
 332
 333 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16240_write_reset, 0);
 334
 335 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("4096");
 336
 337 enum adis16240_chan {
 338         in_supply,
 339         in_aux,
 340         accel_x,
 341         accel_y,
 342         accel_z,
 343         temp,
 344 };
 345
 346 static const u8 adis16240_addresses[6][3] = {
 347         [in_supply] = { ADIS16240_SUPPLY_OUT },
 348         [in_aux] = { ADIS16240_AUX_ADC },
 349         [accel_x] = { ADIS16240_XACCL_OUT, ADIS16240_XACCL_OFF,
 350                       ADIS16240_XPEAK_OUT },
 351         [accel_y] = { ADIS16240_YACCL_OUT, ADIS16240_YACCL_OFF,
 352                       ADIS16240_YPEAK_OUT },
 353         [accel_z] = { ADIS16240_ZACCL_OUT, ADIS16240_ZACCL_OFF,
 354                       ADIS16240_ZPEAK_OUT },
 355         [temp] = { ADIS16240_TEMP_OUT },
 356 };
 357
 358 static int adis16240_read_raw(struct iio_dev *indio_dev,
 359                               struct iio_chan_spec const *chan,
 360                               int *val, int *val2,
 361                               long mask)
 362 {
 363         int ret;
 364         int bits;
 365         u8 addr;
 366         s16 val16;
 367
 368         switch (mask) {
 369         case 0:
 370                 mutex_lock(&indio_dev->mlock);
 371                 addr = adis16240_addresses[chan->address][0];
 372                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 373                 if (ret) {
 374                         mutex_unlock(&indio_dev->mlock);
 375                         return ret;
 376                 }
 377
 378                 if (val16 & ADIS16240_ERROR_ACTIVE) {
 379                         ret = adis16240_check_status(indio_dev);
 380                         if (ret) {
 381                                 mutex_unlock(&indio_dev->mlock);
 382                                 return ret;
 383                         }
 384                 }
 385                 val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
 386                 if (chan->scan_type.sign == 's')
 387                         val16 = (s16)(val16 <<
 388                                       (16 - chan->scan_type.realbits)) >>
 389                                 (16 - chan->scan_type.realbits);
 390                 *val = val16;
 391                 mutex_unlock(&indio_dev->mlock);
 392                 return IIO_VAL_INT;
 393         case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
 394         case (1 << IIO_CHAN_INFO_SCALE_SHARED):
 395                 switch (chan->type) {
 396                 case IIO_IN:
 397                         *val = 0;
 398                         if (chan->channel == 0)
 399                                 *val2 = 4880;
 400                         else
 401                                 return -EINVAL;
 402                         return IIO_VAL_INT_PLUS_MICRO;
 403                 case IIO_TEMP:
 404                         *val = 0;
 405                         *val2 = 244000;
 406                         return IIO_VAL_INT_PLUS_MICRO;
 407                 case IIO_ACCEL:
 408                         *val = 0;
 409                         *val2 = 504062;
 410                         return IIO_VAL_INT_PLUS_MICRO;
 411                 default:
 412                         return -EINVAL;
 413                 }
 414                 break;
 415         case (1 << IIO_CHAN_INFO_PEAK_SCALE_SHARED):
 416                 *val = 6;
 417                 *val2 = 629295;
 418                 return IIO_VAL_INT_PLUS_MICRO;
 419         case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
 420                 *val = 25;
 421                 return IIO_VAL_INT;
 422         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 423                 bits = 10;
 424                 mutex_lock(&indio_dev->mlock);
 425                 addr = adis16240_addresses[chan->address][1];
 426                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 427                 if (ret) {
 428                         mutex_unlock(&indio_dev->mlock);
 429                         return ret;
 430                 }
 431                 val16 &= (1 << bits) - 1;
 432                 val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
 433                 *val = val16;
 434                 mutex_unlock(&indio_dev->mlock);
 435                 return IIO_VAL_INT;
 436         case (1 << IIO_CHAN_INFO_PEAK_SEPARATE):
 437                 bits = 10;
 438                 mutex_lock(&indio_dev->mlock);
 439                 addr = adis16240_addresses[chan->address][2];
 440                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 441                 if (ret) {
 442                         mutex_unlock(&indio_dev->mlock);
 443                         return ret;
 444                 }
 445                 val16 &= (1 << bits) - 1;
 446                 val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
 447                 *val = val16;
 448                 mutex_unlock(&indio_dev->mlock);
 449                 return IIO_VAL_INT;
 450         }
 451         return -EINVAL;
 452 }
 453
 454 static int adis16240_write_raw(struct iio_dev *indio_dev,
 455                                struct iio_chan_spec const *chan,
 456                                int val,
 457                                int val2,
 458                                long mask)
 459 {
 460         int bits = 10;
 461         s16 val16;
 462         u8 addr;
 463         switch (mask) {
 464         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 465                 val16 = val & ((1 << bits) - 1);
 466                 addr = adis16240_addresses[chan->address][1];
 467                 return adis16240_spi_write_reg_16(indio_dev, addr, val16);
 468         }
 469         return -EINVAL;
 470 }
 471
 472 static struct iio_chan_spec adis16240_channels[] = {
 473         IIO_CHAN(IIO_IN, 0, 1, 0, "supply", 0, 0,
 474                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 475                  in_supply, ADIS16240_SCAN_SUPPLY,
 476                  IIO_ST('u', 10, 16, 0), 0),
 477         IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 1, 0,
 478                  0,
 479                  in_aux, ADIS16240_SCAN_AUX_ADC,
 480                  IIO_ST('u', 10, 16, 0), 0),
 481         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X,
 482                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 483                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 484                  accel_x, ADIS16240_SCAN_ACC_X,
 485                  IIO_ST('s', 10, 16, 0), 0),
 486         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y,
 487                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 488                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 489                  accel_y, ADIS16240_SCAN_ACC_Y,
 490                  IIO_ST('s', 10, 16, 0), 0),
 491         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Z,
 492                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 493                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 494                  accel_z, ADIS16240_SCAN_ACC_Z,
 495                  IIO_ST('s', 10, 16, 0), 0),
 496         IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
 497                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 498                  temp, ADIS16240_SCAN_TEMP,
 499                  IIO_ST('u', 10, 16, 0), 0),
 500         IIO_CHAN_SOFT_TIMESTAMP(6)
 501 };
 502
 503 static struct attribute *adis16240_attributes[] = {
 504         &iio_dev_attr_accel_xyz_squared_peak_raw.dev_attr.attr,
 505         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 506         &iio_dev_attr_reset.dev_attr.attr,
 507         NULL
 508 };
 509
 510 static const struct attribute_group adis16240_attribute_group = {
 511         .attrs = adis16240_attributes,
 512 };
 513
 514 static const struct iio_info adis16240_info = {
 515         .attrs = &adis16240_attribute_group,
 516         .read_raw = &adis16240_read_raw,
 517         .write_raw = &adis16240_write_raw,
 518         .driver_module = THIS_MODULE,
 519 };
 520
 521 static int __devinit adis16240_probe(struct spi_device *spi)
 522 {
 523         int ret, regdone = 0;
 524         struct adis16240_state *st;
 525         struct iio_dev *indio_dev;
 526
 527         /* setup the industrialio driver allocated elements */
 528         indio_dev = iio_allocate_device(sizeof(*st));
 529         if (indio_dev == NULL) {
 530                 ret = -ENOMEM;
 531                 goto error_ret;
 532         }
 533         st = iio_priv(indio_dev);
 534         /* this is only used for removal purposes */
 535         spi_set_drvdata(spi, indio_dev);
 536
 537         st->us = spi;
 538         mutex_init(&st->buf_lock);
 539
 540         indio_dev->name = spi->dev.driver->name;
 541         indio_dev->dev.parent = &spi->dev;
 542         indio_dev->info = &adis16240_info;
 543         indio_dev->channels = adis16240_channels;
 544         indio_dev->num_channels = ARRAY_SIZE(adis16240_channels);
 545         indio_dev->modes = INDIO_DIRECT_MODE;
 546
 547         ret = adis16240_configure_ring(indio_dev);
 548         if (ret)
 549                 goto error_free_dev;
 550
 551         ret = iio_device_register(indio_dev);
 552         if (ret)
 553                 goto error_unreg_ring_funcs;
 554         regdone = 1;
 555
 556         ret = iio_ring_buffer_register_ex(indio_dev->ring, 0,
 557                                           adis16240_channels,
 558                                           ARRAY_SIZE(adis16240_channels));
 559         if (ret) {
 560                 printk(KERN_ERR "failed to initialize the ring\n");
 561                 goto error_unreg_ring_funcs;
 562         }
 563
 564         if (spi->irq) {
 565                 ret = adis16240_probe_trigger(indio_dev);
 566                 if (ret)
 567                         goto error_uninitialize_ring;
 568         }
 569
 570         /* Get the device into a sane initial state */
 571         ret = adis16240_initial_setup(indio_dev);
 572         if (ret)
 573                 goto error_remove_trigger;
 574         return 0;
 575
 576 error_remove_trigger:
 577         adis16240_remove_trigger(indio_dev);
 578 error_uninitialize_ring:
 579         iio_ring_buffer_unregister(indio_dev->ring);
 580 error_unreg_ring_funcs:
 581         adis16240_unconfigure_ring(indio_dev);
 582 error_free_dev:
 583         if (regdone)
 584                 iio_device_unregister(indio_dev);
 585         else
 586                 iio_free_device(indio_dev);
 587 error_ret:
 588         return ret;
 589 }
 590
 591 static int adis16240_remove(struct spi_device *spi)
 592 {
 593
 594         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 595
 596         flush_scheduled_work();
 597
 598         adis16240_remove_trigger(indio_dev);
 599         iio_ring_buffer_unregister(indio_dev->ring);
 600         iio_device_unregister(indio_dev);
 601         adis16240_unconfigure_ring(indio_dev);
 602
 603         return 0;
 604 }
 605
 606 static struct spi_driver adis16240_driver = {
 607         .driver = {
 608                 .name = "adis16240",
 609                 .owner = THIS_MODULE,
 610         },
 611         .probe = adis16240_probe,
 612         .remove = __devexit_p(adis16240_remove),
 613 };
 614
 615 static __init int adis16240_init(void)
 616 {
 617         return spi_register_driver(&adis16240_driver);
 618 }
 619 module_init(adis16240_init);
 620
 621 static __exit void adis16240_exit(void)
 622 {
 623         spi_unregister_driver(&adis16240_driver);
 624 }
 625 module_exit(adis16240_exit);
 626
 627 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 628 MODULE_DESCRIPTION("Analog Devices Programmable Impact Sensor and Recorder");
 629 MODULE_LICENSE("GPL v2");