drivers/iio/gyro/adxrs450.c

   1 /*
   2  * ADXRS450/ADXRS453 Digital Output Gyroscope Driver
   3  *
   4  * Copyright 2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/irq.h>
  11 #include <linux/delay.h>
  12 #include <linux/mutex.h>
  13 #include <linux/device.h>
  14 #include <linux/kernel.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/slab.h>
  17 #include <linux/sysfs.h>
  18 #include <linux/list.h>
  19 #include <linux/module.h>
  20
  21 #include <linux/iio/iio.h>
  22 #include <linux/iio/sysfs.h>
  23
  24 #define ADXRS450_STARTUP_DELAY  50 /* ms */
  25
  26 /* The MSB for the spi commands */
  27 #define ADXRS450_SENSOR_DATA    (0x20 << 24)
  28 #define ADXRS450_WRITE_DATA     (0x40 << 24)
  29 #define ADXRS450_READ_DATA      (0x80 << 24)
  30
  31 #define ADXRS450_RATE1  0x00    /* Rate Registers */
  32 #define ADXRS450_TEMP1  0x02    /* Temperature Registers */
  33 #define ADXRS450_LOCST1 0x04    /* Low CST Memory Registers */
  34 #define ADXRS450_HICST1 0x06    /* High CST Memory Registers */
  35 #define ADXRS450_QUAD1  0x08    /* Quad Memory Registers */
  36 #define ADXRS450_FAULT1 0x0A    /* Fault Registers */
  37 #define ADXRS450_PID1   0x0C    /* Part ID Register 1 */
  38 #define ADXRS450_SNH    0x0E    /* Serial Number Registers, 4 bytes */
  39 #define ADXRS450_SNL    0x10
  40 #define ADXRS450_DNC1   0x12    /* Dynamic Null Correction Registers */
  41 /* Check bits */
  42 #define ADXRS450_P      0x01
  43 #define ADXRS450_CHK    0x02
  44 #define ADXRS450_CST    0x04
  45 #define ADXRS450_PWR    0x08
  46 #define ADXRS450_POR    0x10
  47 #define ADXRS450_NVM    0x20
  48 #define ADXRS450_Q      0x40
  49 #define ADXRS450_PLL    0x80
  50 #define ADXRS450_UV     0x100
  51 #define ADXRS450_OV     0x200
  52 #define ADXRS450_AMP    0x400
  53 #define ADXRS450_FAIL   0x800
  54
  55 #define ADXRS450_WRERR_MASK     (0x7 << 29)
  56
  57 #define ADXRS450_MAX_RX 4
  58 #define ADXRS450_MAX_TX 4
  59
  60 #define ADXRS450_GET_ST(a)      ((a >> 26) & 0x3)
  61
  62 enum {
  63         ID_ADXRS450,
  64         ID_ADXRS453,
  65 };
  66
  67 /**
  68  * struct adxrs450_state - device instance specific data
  69  * @us:                 actual spi_device
  70  * @buf_lock:           mutex to protect tx and rx
  71  * @tx:                 transmit buffer
  72  * @rx:                 receive buffer
  73  **/
  74 struct adxrs450_state {
  75         struct spi_device       *us;
  76         struct mutex            buf_lock;
  77         __be32                  tx ____cacheline_aligned;
  78         __be32                  rx;
  79
  80 };
  81
  82 /**
  83  * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
  84  * @indio_dev: device associated with child of actual iio_dev
  85  * @reg_address: the address of the lower of the two registers, which should be
  86  *      an even address, the second register's address is reg_address + 1.
  87  * @val: somewhere to pass back the value read
  88  **/
  89 static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
  90                                     u8 reg_address,
  91                                     u16 *val)
  92 {
  93         struct spi_message msg;
  94         struct adxrs450_state *st = iio_priv(indio_dev);
  95         u32 tx;
  96         int ret;
  97         struct spi_transfer xfers[] = {
  98                 {
  99                         .tx_buf = &st->tx,
 100                         .bits_per_word = 8,
 101                         .len = sizeof(st->tx),
 102                         .cs_change = 1,
 103                 }, {
 104                         .rx_buf = &st->rx,
 105                         .bits_per_word = 8,
 106                         .len = sizeof(st->rx),
 107                 },
 108         };
 109
 110         mutex_lock(&st->buf_lock);
 111         tx = ADXRS450_READ_DATA | (reg_address << 17);
 112
 113         if (!(hweight32(tx) & 1))
 114                 tx |= ADXRS450_P;
 115
 116         st->tx = cpu_to_be32(tx);
 117         spi_message_init(&msg);
 118         spi_message_add_tail(&xfers[0], &msg);
 119         spi_message_add_tail(&xfers[1], &msg);
 120         ret = spi_sync(st->us, &msg);
 121         if (ret) {
 122                 dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
 123                                 reg_address);
 124                 goto error_ret;
 125         }
 126
 127         *val = (be32_to_cpu(st->rx) >> 5) & 0xFFFF;
 128
 129 error_ret:
 130         mutex_unlock(&st->buf_lock);
 131         return ret;
 132 }
 133
 134 /**
 135  * adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
 136  * @indio_dev: device associated with child of actual actual iio_dev
 137  * @reg_address: the address of the lower of the two registers,which should be
 138  *      an even address, the second register's address is reg_address + 1.
 139  * @val: value to be written.
 140  **/
 141 static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
 142                                      u8 reg_address,
 143                                      u16 val)
 144 {
 145         struct adxrs450_state *st = iio_priv(indio_dev);
 146         u32 tx;
 147         int ret;
 148
 149         mutex_lock(&st->buf_lock);
 150         tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
 151
 152         if (!(hweight32(tx) & 1))
 153                 tx |= ADXRS450_P;
 154
 155         st->tx = cpu_to_be32(tx);
 156         ret = spi_write(st->us, &st->tx, sizeof(st->tx));
 157         if (ret)
 158                 dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
 159                         reg_address);
 160         usleep_range(100, 1000); /* enforce sequential transfer delay 0.1ms */
 161         mutex_unlock(&st->buf_lock);
 162         return ret;
 163 }
 164
 165 /**
 166  * adxrs450_spi_sensor_data() - read 2 bytes sensor data
 167  * @indio_dev: device associated with child of actual iio_dev
 168  * @val: somewhere to pass back the value read
 169  **/
 170 static int adxrs450_spi_sensor_data(struct iio_dev *indio_dev, s16 *val)
 171 {
 172         struct spi_message msg;
 173         struct adxrs450_state *st = iio_priv(indio_dev);
 174         int ret;
 175         struct spi_transfer xfers[] = {
 176                 {
 177                         .tx_buf = &st->tx,
 178                         .bits_per_word = 8,
 179                         .len = sizeof(st->tx),
 180                         .cs_change = 1,
 181                 }, {
 182                         .rx_buf = &st->rx,
 183                         .bits_per_word = 8,
 184                         .len = sizeof(st->rx),
 185                 },
 186         };
 187
 188         mutex_lock(&st->buf_lock);
 189         st->tx = cpu_to_be32(ADXRS450_SENSOR_DATA);
 190
 191         spi_message_init(&msg);
 192         spi_message_add_tail(&xfers[0], &msg);
 193         spi_message_add_tail(&xfers[1], &msg);
 194         ret = spi_sync(st->us, &msg);
 195         if (ret) {
 196                 dev_err(&st->us->dev, "Problem while reading sensor data\n");
 197                 goto error_ret;
 198         }
 199
 200         *val = (be32_to_cpu(st->rx) >> 10) & 0xFFFF;
 201
 202 error_ret:
 203         mutex_unlock(&st->buf_lock);
 204         return ret;
 205 }
 206
 207 /**
 208  * adxrs450_spi_initial() - use for initializing procedure.
 209  * @st: device instance specific data
 210  * @val: somewhere to pass back the value read
 211  * @chk: Whether to perform fault check
 212  **/
 213 static int adxrs450_spi_initial(struct adxrs450_state *st,
 214                 u32 *val, char chk)
 215 {
 216         int ret;
 217         u32 tx;
 218         struct spi_transfer xfers = {
 219                 .tx_buf = &st->tx,
 220                 .rx_buf = &st->rx,
 221                 .bits_per_word = 8,
 222                 .len = sizeof(st->tx),
 223         };
 224
 225         mutex_lock(&st->buf_lock);
 226         tx = ADXRS450_SENSOR_DATA;
 227         if (chk)
 228                 tx |= (ADXRS450_CHK | ADXRS450_P);
 229         st->tx = cpu_to_be32(tx);
 230         ret = spi_sync_transfer(st->us, &xfers, 1);
 231         if (ret) {
 232                 dev_err(&st->us->dev, "Problem while reading initializing data\n");
 233                 goto error_ret;
 234         }
 235
 236         *val = be32_to_cpu(st->rx);
 237
 238 error_ret:
 239         mutex_unlock(&st->buf_lock);
 240         return ret;
 241 }
 242
 243 /* Recommended Startup Sequence by spec */
 244 static int adxrs450_initial_setup(struct iio_dev *indio_dev)
 245 {
 246         u32 t;
 247         u16 data;
 248         int ret;
 249         struct adxrs450_state *st = iio_priv(indio_dev);
 250
 251         msleep(ADXRS450_STARTUP_DELAY*2);
 252         ret = adxrs450_spi_initial(st, &t, 1);
 253         if (ret)
 254                 return ret;
 255         if (t != 0x01)
 256                 dev_warn(&st->us->dev, "The initial power on response is not correct! Restart without reset?\n");
 257
 258         msleep(ADXRS450_STARTUP_DELAY);
 259         ret = adxrs450_spi_initial(st, &t, 0);
 260         if (ret)
 261                 return ret;
 262
 263         msleep(ADXRS450_STARTUP_DELAY);
 264         ret = adxrs450_spi_initial(st, &t, 0);
 265         if (ret)
 266                 return ret;
 267         if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
 268                 dev_err(&st->us->dev, "The second response is not correct!\n");
 269                 return -EIO;
 270
 271         }
 272         ret = adxrs450_spi_initial(st, &t, 0);
 273         if (ret)
 274                 return ret;
 275         if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
 276                 dev_err(&st->us->dev, "The third response is not correct!\n");
 277                 return -EIO;
 278
 279         }
 280         ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_FAULT1, &data);
 281         if (ret)
 282                 return ret;
 283         if (data & 0x0fff) {
 284                 dev_err(&st->us->dev, "The device is not in normal status!\n");
 285                 return -EINVAL;
 286         }
 287
 288         return 0;
 289 }
 290
 291 static int adxrs450_write_raw(struct iio_dev *indio_dev,
 292                               struct iio_chan_spec const *chan,
 293                               int val,
 294                               int val2,
 295                               long mask)
 296 {
 297         int ret;
 298         switch (mask) {
 299         case IIO_CHAN_INFO_CALIBBIAS:
 300                 if (val < -0x400 || val >= 0x400)
 301                         return -EINVAL;
 302                 ret = adxrs450_spi_write_reg_16(indio_dev,
 303                                                 ADXRS450_DNC1, val);
 304                 break;
 305         default:
 306                 ret = -EINVAL;
 307                 break;
 308         }
 309         return ret;
 310 }
 311
 312 static int adxrs450_read_raw(struct iio_dev *indio_dev,
 313                              struct iio_chan_spec const *chan,
 314                              int *val,
 315                              int *val2,
 316                              long mask)
 317 {
 318         int ret;
 319         s16 t;
 320
 321         switch (mask) {
 322         case IIO_CHAN_INFO_RAW:
 323                 switch (chan->type) {
 324                 case IIO_ANGL_VEL:
 325                         ret = adxrs450_spi_sensor_data(indio_dev, &t);
 326                         if (ret)
 327                                 break;
 328                         *val = t;
 329                         ret = IIO_VAL_INT;
 330                         break;
 331                 case IIO_TEMP:
 332                         ret = adxrs450_spi_read_reg_16(indio_dev,
 333                                                        ADXRS450_TEMP1, &t);
 334                         if (ret)
 335                                 break;
 336                         *val = (t >> 6) + 225;
 337                         ret = IIO_VAL_INT;
 338                         break;
 339                 default:
 340                         ret = -EINVAL;
 341                         break;
 342                 }
 343                 break;
 344         case IIO_CHAN_INFO_SCALE:
 345                 switch (chan->type) {
 346                 case IIO_ANGL_VEL:
 347                         *val = 0;
 348                         *val2 = 218166;
 349                         return IIO_VAL_INT_PLUS_NANO;
 350                 case IIO_TEMP:
 351                         *val = 200;
 352                         *val2 = 0;
 353                         return IIO_VAL_INT;
 354                 default:
 355                         return -EINVAL;
 356                 }
 357                 break;
 358         case IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW:
 359                 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_QUAD1, &t);
 360                 if (ret)
 361                         break;
 362                 *val = t;
 363                 ret = IIO_VAL_INT;
 364                 break;
 365         case IIO_CHAN_INFO_CALIBBIAS:
 366                 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_DNC1, &t);
 367                 if (ret)
 368                         break;
 369                 *val = sign_extend32(t, 9);
 370                 ret = IIO_VAL_INT;
 371                 break;
 372         default:
 373                 ret = -EINVAL;
 374                 break;
 375         }
 376
 377         return ret;
 378 }
 379
 380 static const struct iio_chan_spec adxrs450_channels[2][2] = {
 381         [ID_ADXRS450] = {
 382                 {
 383                         .type = IIO_ANGL_VEL,
 384                         .modified = 1,
 385                         .channel2 = IIO_MOD_Z,
 386                         .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 387                         IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
 388                         IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT |
 389                         IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
 390                 }, {
 391                         .type = IIO_TEMP,
 392                         .indexed = 1,
 393                         .channel = 0,
 394                         .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 395                         IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
 396                 }
 397         },
 398         [ID_ADXRS453] = {
 399                 {
 400                         .type = IIO_ANGL_VEL,
 401                         .modified = 1,
 402                         .channel2 = IIO_MOD_Z,
 403                         .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 404                         IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
 405                         IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT,
 406                 }, {
 407                         .type = IIO_TEMP,
 408                         .indexed = 1,
 409                         .channel = 0,
 410                         .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 411                         IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
 412                 }
 413         },
 414 };
 415
 416 static const struct iio_info adxrs450_info = {
 417         .driver_module = THIS_MODULE,
 418         .read_raw = &adxrs450_read_raw,
 419         .write_raw = &adxrs450_write_raw,
 420 };
 421
 422 static int adxrs450_probe(struct spi_device *spi)
 423 {
 424         int ret;
 425         struct adxrs450_state *st;
 426         struct iio_dev *indio_dev;
 427
 428         /* setup the industrialio driver allocated elements */
 429         indio_dev = iio_device_alloc(sizeof(*st));
 430         if (indio_dev == NULL) {
 431                 ret = -ENOMEM;
 432                 goto error_ret;
 433         }
 434         st = iio_priv(indio_dev);
 435         st->us = spi;
 436         mutex_init(&st->buf_lock);
 437         /* This is only used for removal purposes */
 438         spi_set_drvdata(spi, indio_dev);
 439
 440         indio_dev->dev.parent = &spi->dev;
 441         indio_dev->info = &adxrs450_info;
 442         indio_dev->modes = INDIO_DIRECT_MODE;
 443         indio_dev->channels =
 444                 adxrs450_channels[spi_get_device_id(spi)->driver_data];
 445         indio_dev->num_channels = ARRAY_SIZE(adxrs450_channels);
 446         indio_dev->name = spi->dev.driver->name;
 447
 448         ret = iio_device_register(indio_dev);
 449         if (ret)
 450                 goto error_free_dev;
 451
 452         /* Get the device into a sane initial state */
 453         ret = adxrs450_initial_setup(indio_dev);
 454         if (ret)
 455                 goto error_initial;
 456         return 0;
 457 error_initial:
 458         iio_device_unregister(indio_dev);
 459 error_free_dev:
 460         iio_device_free(indio_dev);
 461
 462 error_ret:
 463         return ret;
 464 }
 465
 466 static int adxrs450_remove(struct spi_device *spi)
 467 {
 468         iio_device_unregister(spi_get_drvdata(spi));
 469         iio_device_free(spi_get_drvdata(spi));
 470
 471         return 0;
 472 }
 473
 474 static const struct spi_device_id adxrs450_id[] = {
 475         {"adxrs450", ID_ADXRS450},
 476         {"adxrs453", ID_ADXRS453},
 477         {}
 478 };
 479 MODULE_DEVICE_TABLE(spi, adxrs450_id);
 480
 481 static struct spi_driver adxrs450_driver = {
 482         .driver = {
 483                 .name = "adxrs450",
 484                 .owner = THIS_MODULE,
 485         },
 486         .probe = adxrs450_probe,
 487         .remove = adxrs450_remove,
 488         .id_table       = adxrs450_id,
 489 };
 490 module_spi_driver(adxrs450_driver);
 491
 492 MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
 493 MODULE_DESCRIPTION("Analog Devices ADXRS450/ADXRS453 Gyroscope SPI driver");
 494 MODULE_LICENSE("GPL v2");