release/src-rt-6.x.4708/linux/linux-2.6.36/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 device *dev);
  32
  33 /**
  34  * adis16240_spi_write_reg_8() - write single byte to a register
  35  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  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 device *dev,
  40                 u8 reg_address,
  41                 u8 val)
  42 {
  43         int ret;
  44         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  45         struct adis16240_state *st = iio_dev_get_devdata(indio_dev);
  46
  47         mutex_lock(&st->buf_lock);
  48         st->tx[0] = ADIS16240_WRITE_REG(reg_address);
  49         st->tx[1] = val;
  50
  51         ret = spi_write(st->us, st->tx, 2);
  52         mutex_unlock(&st->buf_lock);
  53
  54         return ret;
  55 }
  56
  57 /**
  58  * adis16240_spi_write_reg_16() - write 2 bytes to a pair of registers
  59  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  60  * @reg_address: the address of the lower of the two registers. Second register
  61  *               is assumed to have address one greater.
  62  * @val: value to be written
  63  **/
  64 static int adis16240_spi_write_reg_16(struct device *dev,
  65                 u8 lower_reg_address,
  66                 u16 value)
  67 {
  68         int ret;
  69         struct spi_message msg;
  70         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  71         struct adis16240_state *st = iio_dev_get_devdata(indio_dev);
  72         struct spi_transfer xfers[] = {
  73                 {
  74                         .tx_buf = st->tx,
  75                         .bits_per_word = 8,
  76                         .len = 2,
  77                         .cs_change = 1,
  78                         .delay_usecs = 35,
  79                 }, {
  80                         .tx_buf = st->tx + 2,
  81                         .bits_per_word = 8,
  82                         .len = 2,
  83                         .cs_change = 1,
  84                         .delay_usecs = 35,
  85                 },
  86         };
  87
  88         mutex_lock(&st->buf_lock);
  89         st->tx[0] = ADIS16240_WRITE_REG(lower_reg_address);
  90         st->tx[1] = value & 0xFF;
  91         st->tx[2] = ADIS16240_WRITE_REG(lower_reg_address + 1);
  92         st->tx[3] = (value >> 8) & 0xFF;
  93
  94         spi_message_init(&msg);
  95         spi_message_add_tail(&xfers[0], &msg);
  96         spi_message_add_tail(&xfers[1], &msg);
  97         ret = spi_sync(st->us, &msg);
  98         mutex_unlock(&st->buf_lock);
  99
 100         return ret;
 101 }
 102
 103 /**
 104  * adis16240_spi_read_reg_16() - read 2 bytes from a 16-bit register
 105  * @dev: device associated with child of actual device (iio_dev or iio_trig)
 106  * @reg_address: the address of the lower of the two registers. Second register
 107  *               is assumed to have address one greater.
 108  * @val: somewhere to pass back the value read
 109  **/
 110 static int adis16240_spi_read_reg_16(struct device *dev,
 111                 u8 lower_reg_address,
 112                 u16 *val)
 113 {
 114         struct spi_message msg;
 115         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 116         struct adis16240_state *st = iio_dev_get_devdata(indio_dev);
 117         int ret;
 118         struct spi_transfer xfers[] = {
 119                 {
 120                         .tx_buf = st->tx,
 121                         .bits_per_word = 8,
 122                         .len = 2,
 123                         .cs_change = 1,
 124                         .delay_usecs = 35,
 125                 }, {
 126                         .rx_buf = st->rx,
 127                         .bits_per_word = 8,
 128                         .len = 2,
 129                         .cs_change = 1,
 130                         .delay_usecs = 35,
 131                 },
 132         };
 133
 134         mutex_lock(&st->buf_lock);
 135         st->tx[0] = ADIS16240_READ_REG(lower_reg_address);
 136         st->tx[1] = 0;
 137         st->tx[2] = 0;
 138         st->tx[3] = 0;
 139
 140         spi_message_init(&msg);
 141         spi_message_add_tail(&xfers[0], &msg);
 142         spi_message_add_tail(&xfers[1], &msg);
 143         ret = spi_sync(st->us, &msg);
 144         if (ret) {
 145                 dev_err(&st->us->dev,
 146                         "problem when reading 16 bit register 0x%02X",
 147                         lower_reg_address);
 148                 goto error_ret;
 149         }
 150         *val = (st->rx[0] << 8) | st->rx[1];
 151
 152 error_ret:
 153         mutex_unlock(&st->buf_lock);
 154         return ret;
 155 }
 156
 157 static ssize_t adis16240_spi_read_signed(struct device *dev,
 158                 struct device_attribute *attr,
 159                 char *buf,
 160                 unsigned bits)
 161 {
 162         int ret;
 163         s16 val = 0;
 164         unsigned shift = 16 - bits;
 165         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 166
 167         ret = adis16240_spi_read_reg_16(dev, this_attr->address, (u16 *)&val);
 168         if (ret)
 169                 return ret;
 170
 171         if (val & ADIS16240_ERROR_ACTIVE)
 172                 adis16240_check_status(dev);
 173
 174         val = ((s16)(val << shift) >> shift);
 175         return sprintf(buf, "%d\n", val);
 176 }
 177
 178 static ssize_t adis16240_read_10bit_unsigned(struct device *dev,
 179                 struct device_attribute *attr,
 180                 char *buf)
 181 {
 182         int ret;
 183         u16 val = 0;
 184         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 185
 186         ret = adis16240_spi_read_reg_16(dev, this_attr->address, &val);
 187         if (ret)
 188                 return ret;
 189
 190         if (val & ADIS16240_ERROR_ACTIVE)
 191                 adis16240_check_status(dev);
 192
 193         return sprintf(buf, "%u\n", val & 0x03FF);
 194 }
 195
 196 static ssize_t adis16240_read_10bit_signed(struct device *dev,
 197                 struct device_attribute *attr,
 198                 char *buf)
 199 {
 200         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 201         ssize_t ret;
 202
 203         /* Take the iio_dev status lock */
 204         mutex_lock(&indio_dev->mlock);
 205         ret =  adis16240_spi_read_signed(dev, attr, buf, 10);
 206         mutex_unlock(&indio_dev->mlock);
 207
 208         return ret;
 209 }
 210
 211 static ssize_t adis16240_read_12bit_signed(struct device *dev,
 212                 struct device_attribute *attr,
 213                 char *buf)
 214 {
 215         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 216         ssize_t ret;
 217
 218         /* Take the iio_dev status lock */
 219         mutex_lock(&indio_dev->mlock);
 220         ret =  adis16240_spi_read_signed(dev, attr, buf, 12);
 221         mutex_unlock(&indio_dev->mlock);
 222
 223         return ret;
 224 }
 225
 226 static ssize_t adis16240_write_16bit(struct device *dev,
 227                 struct device_attribute *attr,
 228                 const char *buf,
 229                 size_t len)
 230 {
 231         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 232         int ret;
 233         long val;
 234
 235         ret = strict_strtol(buf, 10, &val);
 236         if (ret)
 237                 goto error_ret;
 238         ret = adis16240_spi_write_reg_16(dev, this_attr->address, val);
 239
 240 error_ret:
 241         return ret ? ret : len;
 242 }
 243
 244 static int adis16240_reset(struct device *dev)
 245 {
 246         int ret;
 247         ret = adis16240_spi_write_reg_8(dev,
 248                         ADIS16240_GLOB_CMD,
 249                         ADIS16240_GLOB_CMD_SW_RESET);
 250         if (ret)
 251                 dev_err(dev, "problem resetting device");
 252
 253         return ret;
 254 }
 255
 256 static ssize_t adis16240_write_reset(struct device *dev,
 257                 struct device_attribute *attr,
 258                 const char *buf, size_t len)
 259 {
 260         if (len < 1)
 261                 return -EINVAL;
 262         switch (buf[0]) {
 263         case '1':
 264         case 'y':
 265         case 'Y':
 266                 return adis16240_reset(dev);
 267         }
 268         return -EINVAL;
 269 }
 270
 271 int adis16240_set_irq(struct device *dev, bool enable)
 272 {
 273         int ret = 0;
 274         u16 msc;
 275
 276         ret = adis16240_spi_read_reg_16(dev, ADIS16240_MSC_CTRL, &msc);
 277         if (ret)
 278                 goto error_ret;
 279
 280         msc |= ADIS16240_MSC_CTRL_ACTIVE_HIGH;
 281         msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_DIO2;
 282         if (enable)
 283                 msc |= ADIS16240_MSC_CTRL_DATA_RDY_EN;
 284         else
 285                 msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_EN;
 286
 287         ret = adis16240_spi_write_reg_16(dev, ADIS16240_MSC_CTRL, msc);
 288
 289 error_ret:
 290         return ret;
 291 }
 292
 293 static int adis16240_self_test(struct device *dev)
 294 {
 295         int ret;
 296         ret = adis16240_spi_write_reg_16(dev,
 297                         ADIS16240_MSC_CTRL,
 298                         ADIS16240_MSC_CTRL_SELF_TEST_EN);
 299         if (ret) {
 300                 dev_err(dev, "problem starting self test");
 301                 goto err_ret;
 302         }
 303
 304         msleep(ADIS16240_STARTUP_DELAY);
 305
 306         adis16240_check_status(dev);
 307
 308 err_ret:
 309         return ret;
 310 }
 311
 312 static int adis16240_check_status(struct device *dev)
 313 {
 314         u16 status;
 315         int ret;
 316
 317         ret = adis16240_spi_read_reg_16(dev, ADIS16240_DIAG_STAT, &status);
 318
 319         if (ret < 0) {
 320                 dev_err(dev, "Reading status failed\n");
 321                 goto error_ret;
 322         }
 323
 324         ret = status & 0x2F;
 325         if (status & ADIS16240_DIAG_STAT_PWRON_FAIL)
 326                 dev_err(dev, "Power-on, self-test fail\n");
 327         if (status & ADIS16240_DIAG_STAT_SPI_FAIL)
 328                 dev_err(dev, "SPI failure\n");
 329         if (status & ADIS16240_DIAG_STAT_FLASH_UPT)
 330                 dev_err(dev, "Flash update failed\n");
 331         if (status & ADIS16240_DIAG_STAT_POWER_HIGH)
 332                 dev_err(dev, "Power supply above 3.625V\n");
 333         if (status & ADIS16240_DIAG_STAT_POWER_LOW)
 334                 dev_err(dev, "Power supply below 2.225V\n");
 335
 336 error_ret:
 337         return ret;
 338 }
 339
 340 static int adis16240_initial_setup(struct adis16240_state *st)
 341 {
 342         int ret;
 343         struct device *dev = &st->indio_dev->dev;
 344
 345         /* Disable IRQ */
 346         ret = adis16240_set_irq(dev, false);
 347         if (ret) {
 348                 dev_err(dev, "disable irq failed");
 349                 goto err_ret;
 350         }
 351
 352         /* Do self test */
 353         ret = adis16240_self_test(dev);
 354         if (ret) {
 355                 dev_err(dev, "self test failure");
 356                 goto err_ret;
 357         }
 358
 359         /* Read status register to check the result */
 360         ret = adis16240_check_status(dev);
 361         if (ret) {
 362                 adis16240_reset(dev);
 363                 dev_err(dev, "device not playing ball -> reset");
 364                 msleep(ADIS16240_STARTUP_DELAY);
 365                 ret = adis16240_check_status(dev);
 366                 if (ret) {
 367                         dev_err(dev, "giving up");
 368                         goto err_ret;
 369                 }
 370         }
 371
 372         printk(KERN_INFO DRIVER_NAME ": at CS%d (irq %d)\n",
 373                         st->us->chip_select, st->us->irq);
 374
 375 err_ret:
 376         return ret;
 377 }
 378
 379 static IIO_DEV_ATTR_IN_NAMED_RAW(supply, adis16240_read_10bit_unsigned,
 380                 ADIS16240_SUPPLY_OUT);
 381 static IIO_DEV_ATTR_IN_RAW(0, adis16240_read_10bit_signed,
 382                 ADIS16240_AUX_ADC);
 383 static IIO_CONST_ATTR(in_supply_scale, "0.00488");
 384 static IIO_DEV_ATTR_ACCEL_X(adis16240_read_10bit_signed,
 385                 ADIS16240_XACCL_OUT);
 386 static IIO_DEVICE_ATTR(accel_x_peak_raw, S_IRUGO,
 387                        adis16240_read_10bit_signed, NULL,
 388                        ADIS16240_XPEAK_OUT);
 389 static IIO_DEV_ATTR_ACCEL_Y(adis16240_read_10bit_signed,
 390                 ADIS16240_YACCL_OUT);
 391 static IIO_DEVICE_ATTR(accel_y_peak_raw, S_IRUGO,
 392                        adis16240_read_10bit_signed, NULL,
 393                        ADIS16240_YPEAK_OUT);
 394 static IIO_DEV_ATTR_ACCEL_Z(adis16240_read_10bit_signed,
 395                 ADIS16240_ZACCL_OUT);
 396 static IIO_DEVICE_ATTR(accel_z_peak_raw, S_IRUGO,
 397                        adis16240_read_10bit_signed, NULL,
 398                        ADIS16240_ZPEAK_OUT);
 399
 400 static IIO_DEVICE_ATTR(accel_xyz_squared_peak_raw, S_IRUGO,
 401                        adis16240_read_12bit_signed, NULL,
 402                        ADIS16240_XYZPEAK_OUT);
 403 static IIO_DEV_ATTR_ACCEL_X_OFFSET(S_IWUSR | S_IRUGO,
 404                 adis16240_read_10bit_signed,
 405                 adis16240_write_16bit,
 406                 ADIS16240_XACCL_OFF);
 407 static IIO_DEV_ATTR_ACCEL_Y_OFFSET(S_IWUSR | S_IRUGO,
 408                 adis16240_read_10bit_signed,
 409                 adis16240_write_16bit,
 410                 ADIS16240_YACCL_OFF);
 411 static IIO_DEV_ATTR_ACCEL_Z_OFFSET(S_IWUSR | S_IRUGO,
 412                 adis16240_read_10bit_signed,
 413                 adis16240_write_16bit,
 414                 ADIS16240_ZACCL_OFF);
 415 static IIO_DEV_ATTR_TEMP_RAW(adis16240_read_10bit_unsigned);
 416 static IIO_CONST_ATTR(temp_scale, "0.244");
 417
 418 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16240_write_reset, 0);
 419
 420 static IIO_CONST_ATTR_AVAIL_SAMP_FREQ("4096");
 421
 422 static IIO_CONST_ATTR(name, "adis16240");
 423
 424 static struct attribute *adis16240_event_attributes[] = {
 425         NULL
 426 };
 427
 428 static struct attribute_group adis16240_event_attribute_group = {
 429         .attrs = adis16240_event_attributes,
 430 };
 431
 432 static struct attribute *adis16240_attributes[] = {
 433         &iio_dev_attr_in_supply_raw.dev_attr.attr,
 434         &iio_const_attr_in_supply_scale.dev_attr.attr,
 435         &iio_dev_attr_in0_raw.dev_attr.attr,
 436         &iio_dev_attr_accel_x_raw.dev_attr.attr,
 437         &iio_dev_attr_accel_x_offset.dev_attr.attr,
 438         &iio_dev_attr_accel_x_peak_raw.dev_attr.attr,
 439         &iio_dev_attr_accel_y_raw.dev_attr.attr,
 440         &iio_dev_attr_accel_y_offset.dev_attr.attr,
 441         &iio_dev_attr_accel_y_peak_raw.dev_attr.attr,
 442         &iio_dev_attr_accel_z_raw.dev_attr.attr,
 443         &iio_dev_attr_accel_z_offset.dev_attr.attr,
 444         &iio_dev_attr_accel_z_peak_raw.dev_attr.attr,
 445         &iio_dev_attr_accel_xyz_squared_peak_raw.dev_attr.attr,
 446         &iio_dev_attr_temp_raw.dev_attr.attr,
 447         &iio_const_attr_temp_scale.dev_attr.attr,
 448         &iio_const_attr_available_sampling_frequency.dev_attr.attr,
 449         &iio_dev_attr_reset.dev_attr.attr,
 450         &iio_const_attr_name.dev_attr.attr,
 451         NULL
 452 };
 453
 454 static const struct attribute_group adis16240_attribute_group = {
 455         .attrs = adis16240_attributes,
 456 };
 457
 458 static int __devinit adis16240_probe(struct spi_device *spi)
 459 {
 460         int ret, regdone = 0;
 461         struct adis16240_state *st = kzalloc(sizeof *st, GFP_KERNEL);
 462         if (!st) {
 463                 ret =  -ENOMEM;
 464                 goto error_ret;
 465         }
 466         /* this is only used for removal purposes */
 467         spi_set_drvdata(spi, st);
 468
 469         /* Allocate the comms buffers */
 470         st->rx = kzalloc(sizeof(*st->rx)*ADIS16240_MAX_RX, GFP_KERNEL);
 471         if (st->rx == NULL) {
 472                 ret = -ENOMEM;
 473                 goto error_free_st;
 474         }
 475         st->tx = kzalloc(sizeof(*st->tx)*ADIS16240_MAX_TX, GFP_KERNEL);
 476         if (st->tx == NULL) {
 477                 ret = -ENOMEM;
 478                 goto error_free_rx;
 479         }
 480         st->us = spi;
 481         mutex_init(&st->buf_lock);
 482         /* setup the industrialio driver allocated elements */
 483         st->indio_dev = iio_allocate_device();
 484         if (st->indio_dev == NULL) {
 485                 ret = -ENOMEM;
 486                 goto error_free_tx;
 487         }
 488
 489         st->indio_dev->dev.parent = &spi->dev;
 490         st->indio_dev->num_interrupt_lines = 1;
 491         st->indio_dev->event_attrs = &adis16240_event_attribute_group;
 492         st->indio_dev->attrs = &adis16240_attribute_group;
 493         st->indio_dev->dev_data = (void *)(st);
 494         st->indio_dev->driver_module = THIS_MODULE;
 495         st->indio_dev->modes = INDIO_DIRECT_MODE;
 496
 497         ret = adis16240_configure_ring(st->indio_dev);
 498         if (ret)
 499                 goto error_free_dev;
 500
 501         ret = iio_device_register(st->indio_dev);
 502         if (ret)
 503                 goto error_unreg_ring_funcs;
 504         regdone = 1;
 505
 506         ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
 507         if (ret) {
 508                 printk(KERN_ERR "failed to initialize the ring\n");
 509                 goto error_unreg_ring_funcs;
 510         }
 511
 512         if (spi->irq) {
 513                 ret = iio_register_interrupt_line(spi->irq,
 514                                 st->indio_dev,
 515                                 0,
 516                                 IRQF_TRIGGER_RISING,
 517                                 "adis16240");
 518                 if (ret)
 519                         goto error_uninitialize_ring;
 520
 521                 ret = adis16240_probe_trigger(st->indio_dev);
 522                 if (ret)
 523                         goto error_unregister_line;
 524         }
 525
 526         /* Get the device into a sane initial state */
 527         ret = adis16240_initial_setup(st);
 528         if (ret)
 529                 goto error_remove_trigger;
 530         return 0;
 531
 532 error_remove_trigger:
 533         adis16240_remove_trigger(st->indio_dev);
 534 error_unregister_line:
 535         if (spi->irq)
 536                 iio_unregister_interrupt_line(st->indio_dev, 0);
 537 error_uninitialize_ring:
 538         iio_ring_buffer_unregister(st->indio_dev->ring);
 539 error_unreg_ring_funcs:
 540         adis16240_unconfigure_ring(st->indio_dev);
 541 error_free_dev:
 542         if (regdone)
 543                 iio_device_unregister(st->indio_dev);
 544         else
 545                 iio_free_device(st->indio_dev);
 546 error_free_tx:
 547         kfree(st->tx);
 548 error_free_rx:
 549         kfree(st->rx);
 550 error_free_st:
 551         kfree(st);
 552 error_ret:
 553         return ret;
 554 }
 555
 556 static int adis16240_remove(struct spi_device *spi)
 557 {
 558         struct adis16240_state *st = spi_get_drvdata(spi);
 559         struct iio_dev *indio_dev = st->indio_dev;
 560
 561         flush_scheduled_work();
 562
 563         adis16240_remove_trigger(indio_dev);
 564         if (spi->irq)
 565                 iio_unregister_interrupt_line(indio_dev, 0);
 566
 567         iio_ring_buffer_unregister(indio_dev->ring);
 568         iio_device_unregister(indio_dev);
 569         adis16240_unconfigure_ring(indio_dev);
 570         kfree(st->tx);
 571         kfree(st->rx);
 572         kfree(st);
 573
 574         return 0;
 575 }
 576
 577 static struct spi_driver adis16240_driver = {
 578         .driver = {
 579                 .name = "adis16240",
 580                 .owner = THIS_MODULE,
 581         },
 582         .probe = adis16240_probe,
 583         .remove = __devexit_p(adis16240_remove),
 584 };
 585
 586 static __init int adis16240_init(void)
 587 {
 588         return spi_register_driver(&adis16240_driver);
 589 }
 590 module_init(adis16240_init);
 591
 592 static __exit void adis16240_exit(void)
 593 {
 594         spi_unregister_driver(&adis16240_driver);
 595 }
 596 module_exit(adis16240_exit);
 597
 598 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 599 MODULE_DESCRIPTION("Analog Devices Programmable Impact Sensor and Recorder");
 600 MODULE_LICENSE("GPL v2");