1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2022 ROHM Semiconductors 4 * 5 * ROHM/KIONIX KX022A accelerometer driver 6 */ 7 8 #include <linux/delay.h> 9 #include <linux/device.h> 10 #include <linux/interrupt.h> 11 #include <linux/module.h> 12 #include <linux/moduleparam.h> 13 #include <linux/mutex.h> 14 #include <linux/property.h> 15 #include <linux/regmap.h> 16 #include <linux/regulator/consumer.h> 17 #include <linux/slab.h> 18 #include <linux/string_helpers.h> 19 #include <linux/units.h> 20 21 #include <linux/iio/iio.h> 22 #include <linux/iio/sysfs.h> 23 #include <linux/iio/trigger.h> 24 #include <linux/iio/trigger_consumer.h> 25 #include <linux/iio/triggered_buffer.h> 26 27 #include "kionix-kx022a.h" 28 29 /* 30 * The KX022A has FIFO which can store 43 samples of HiRes data from 2 31 * channels. This equals to 43 (samples) * 3 (channels) * 2 (bytes/sample) to 32 * 258 bytes of sample data. The quirk to know is that the amount of bytes in 33 * the FIFO is advertised via 8 bit register (max value 255). The thing to note 34 * is that full 258 bytes of data is indicated using the max value 255. 35 */ 36 #define KX022A_FIFO_LENGTH 43 37 #define KX022A_FIFO_FULL_VALUE 255 38 #define KX022A_SOFT_RESET_WAIT_TIME_US (5 * USEC_PER_MSEC) 39 #define KX022A_SOFT_RESET_TOTAL_WAIT_TIME_US (500 * USEC_PER_MSEC) 40 41 /* 3 axis, 2 bytes of data for each of the axis */ 42 #define KX022A_FIFO_SAMPLES_SIZE_BYTES 6 43 #define KX022A_FIFO_MAX_BYTES \ 44 (KX022A_FIFO_LENGTH * KX022A_FIFO_SAMPLES_SIZE_BYTES) 45 46 enum { 47 KX022A_STATE_SAMPLE, 48 KX022A_STATE_FIFO, 49 }; 50 51 /* Regmap configs */ 52 static const struct regmap_range kx022a_volatile_ranges[] = { 53 { 54 .range_min = KX022A_REG_XHP_L, 55 .range_max = KX022A_REG_COTR, 56 }, { 57 .range_min = KX022A_REG_TSCP, 58 .range_max = KX022A_REG_INT_REL, 59 }, { 60 /* The reset bit will be cleared by sensor */ 61 .range_min = KX022A_REG_CNTL2, 62 .range_max = KX022A_REG_CNTL2, 63 }, { 64 .range_min = KX022A_REG_BUF_STATUS_1, 65 .range_max = KX022A_REG_BUF_READ, 66 }, 67 }; 68 69 static const struct regmap_access_table kx022a_volatile_regs = { 70 .yes_ranges = &kx022a_volatile_ranges[0], 71 .n_yes_ranges = ARRAY_SIZE(kx022a_volatile_ranges), 72 }; 73 74 static const struct regmap_range kx022a_precious_ranges[] = { 75 { 76 .range_min = KX022A_REG_INT_REL, 77 .range_max = KX022A_REG_INT_REL, 78 }, 79 }; 80 81 static const struct regmap_access_table kx022a_precious_regs = { 82 .yes_ranges = &kx022a_precious_ranges[0], 83 .n_yes_ranges = ARRAY_SIZE(kx022a_precious_ranges), 84 }; 85 86 /* 87 * The HW does not set WHO_AM_I reg as read-only but we don't want to write it 88 * so we still include it in the read-only ranges. 89 */ 90 static const struct regmap_range kx022a_read_only_ranges[] = { 91 { 92 .range_min = KX022A_REG_XHP_L, 93 .range_max = KX022A_REG_INT_REL, 94 }, { 95 .range_min = KX022A_REG_BUF_STATUS_1, 96 .range_max = KX022A_REG_BUF_STATUS_2, 97 }, { 98 .range_min = KX022A_REG_BUF_READ, 99 .range_max = KX022A_REG_BUF_READ, 100 }, 101 }; 102 103 static const struct regmap_access_table kx022a_ro_regs = { 104 .no_ranges = &kx022a_read_only_ranges[0], 105 .n_no_ranges = ARRAY_SIZE(kx022a_read_only_ranges), 106 }; 107 108 static const struct regmap_range kx022a_write_only_ranges[] = { 109 { 110 .range_min = KX022A_REG_BTS_WUF_TH, 111 .range_max = KX022A_REG_BTS_WUF_TH, 112 }, { 113 .range_min = KX022A_REG_MAN_WAKE, 114 .range_max = KX022A_REG_MAN_WAKE, 115 }, { 116 .range_min = KX022A_REG_SELF_TEST, 117 .range_max = KX022A_REG_SELF_TEST, 118 }, { 119 .range_min = KX022A_REG_BUF_CLEAR, 120 .range_max = KX022A_REG_BUF_CLEAR, 121 }, 122 }; 123 124 static const struct regmap_access_table kx022a_wo_regs = { 125 .no_ranges = &kx022a_write_only_ranges[0], 126 .n_no_ranges = ARRAY_SIZE(kx022a_write_only_ranges), 127 }; 128 129 static const struct regmap_range kx022a_noinc_read_ranges[] = { 130 { 131 .range_min = KX022A_REG_BUF_READ, 132 .range_max = KX022A_REG_BUF_READ, 133 }, 134 }; 135 136 static const struct regmap_access_table kx022a_nir_regs = { 137 .yes_ranges = &kx022a_noinc_read_ranges[0], 138 .n_yes_ranges = ARRAY_SIZE(kx022a_noinc_read_ranges), 139 }; 140 141 const struct regmap_config kx022a_regmap = { 142 .reg_bits = 8, 143 .val_bits = 8, 144 .volatile_table = &kx022a_volatile_regs, 145 .rd_table = &kx022a_wo_regs, 146 .wr_table = &kx022a_ro_regs, 147 .rd_noinc_table = &kx022a_nir_regs, 148 .precious_table = &kx022a_precious_regs, 149 .max_register = KX022A_MAX_REGISTER, 150 .cache_type = REGCACHE_RBTREE, 151 }; 152 EXPORT_SYMBOL_NS_GPL(kx022a_regmap, IIO_KX022A); 153 154 struct kx022a_data { 155 struct regmap *regmap; 156 struct iio_trigger *trig; 157 struct device *dev; 158 struct iio_mount_matrix orientation; 159 int64_t timestamp, old_timestamp; 160 161 int irq; 162 int inc_reg; 163 int ien_reg; 164 165 unsigned int state; 166 unsigned int odr_ns; 167 168 bool trigger_enabled; 169 /* 170 * Prevent toggling the sensor stby/active state (PC1 bit) in the 171 * middle of a configuration, or when the fifo is enabled. Also, 172 * protect the data stored/retrieved from this structure from 173 * concurrent accesses. 174 */ 175 struct mutex mutex; 176 u8 watermark; 177 178 /* 3 x 16bit accel data + timestamp */ 179 __le16 buffer[8] __aligned(IIO_DMA_MINALIGN); 180 struct { 181 __le16 channels[3]; 182 s64 ts __aligned(8); 183 } scan; 184 }; 185 186 static const struct iio_mount_matrix * 187 kx022a_get_mount_matrix(const struct iio_dev *idev, 188 const struct iio_chan_spec *chan) 189 { 190 struct kx022a_data *data = iio_priv(idev); 191 192 return &data->orientation; 193 } 194 195 enum { 196 AXIS_X, 197 AXIS_Y, 198 AXIS_Z, 199 AXIS_MAX 200 }; 201 202 static const unsigned long kx022a_scan_masks[] = { 203 BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z), 0 204 }; 205 206 static const struct iio_chan_spec_ext_info kx022a_ext_info[] = { 207 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kx022a_get_mount_matrix), 208 { } 209 }; 210 211 #define KX022A_ACCEL_CHAN(axis, index) \ 212 { \ 213 .type = IIO_ACCEL, \ 214 .modified = 1, \ 215 .channel2 = IIO_MOD_##axis, \ 216 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 217 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 218 BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 219 .info_mask_shared_by_type_available = \ 220 BIT(IIO_CHAN_INFO_SCALE) | \ 221 BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 222 .ext_info = kx022a_ext_info, \ 223 .address = KX022A_REG_##axis##OUT_L, \ 224 .scan_index = index, \ 225 .scan_type = { \ 226 .sign = 's', \ 227 .realbits = 16, \ 228 .storagebits = 16, \ 229 .endianness = IIO_LE, \ 230 }, \ 231 } 232 233 static const struct iio_chan_spec kx022a_channels[] = { 234 KX022A_ACCEL_CHAN(X, 0), 235 KX022A_ACCEL_CHAN(Y, 1), 236 KX022A_ACCEL_CHAN(Z, 2), 237 IIO_CHAN_SOFT_TIMESTAMP(3), 238 }; 239 240 /* 241 * The sensor HW can support ODR up to 1600 Hz, which is beyond what most of the 242 * Linux CPUs can handle without dropping samples. Also, the low power mode is 243 * not available for higher sample rates. Thus, the driver only supports 200 Hz 244 * and slower ODRs. The slowest is 0.78 Hz. 245 */ 246 static const int kx022a_accel_samp_freq_table[][2] = { 247 { 0, 780000 }, 248 { 1, 563000 }, 249 { 3, 125000 }, 250 { 6, 250000 }, 251 { 12, 500000 }, 252 { 25, 0 }, 253 { 50, 0 }, 254 { 100, 0 }, 255 { 200, 0 }, 256 }; 257 258 static const unsigned int kx022a_odrs[] = { 259 1282051282, 260 639795266, 261 320 * MEGA, 262 160 * MEGA, 263 80 * MEGA, 264 40 * MEGA, 265 20 * MEGA, 266 10 * MEGA, 267 5 * MEGA, 268 }; 269 270 /* 271 * range is typically +-2G/4G/8G/16G, distributed over the amount of bits. 272 * The scale table can be calculated using 273 * (range / 2^bits) * g = (range / 2^bits) * 9.80665 m/s^2 274 * => KX022A uses 16 bit (HiRes mode - assume the low 8 bits are zeroed 275 * in low-power mode(?) ) 276 * => +/-2G => 4 / 2^16 * 9,80665 277 * => +/-2G - 0.000598550415 278 * +/-4G - 0.00119710083 279 * +/-8G - 0.00239420166 280 * +/-16G - 0.00478840332 281 */ 282 static const int kx022a_scale_table[][2] = { 283 { 0, 598550 }, 284 { 0, 1197101 }, 285 { 0, 2394202 }, 286 { 0, 4788403 }, 287 }; 288 289 static int kx022a_read_avail(struct iio_dev *indio_dev, 290 struct iio_chan_spec const *chan, 291 const int **vals, int *type, int *length, 292 long mask) 293 { 294 switch (mask) { 295 case IIO_CHAN_INFO_SAMP_FREQ: 296 *vals = (const int *)kx022a_accel_samp_freq_table; 297 *length = ARRAY_SIZE(kx022a_accel_samp_freq_table) * 298 ARRAY_SIZE(kx022a_accel_samp_freq_table[0]); 299 *type = IIO_VAL_INT_PLUS_MICRO; 300 return IIO_AVAIL_LIST; 301 case IIO_CHAN_INFO_SCALE: 302 *vals = (const int *)kx022a_scale_table; 303 *length = ARRAY_SIZE(kx022a_scale_table) * 304 ARRAY_SIZE(kx022a_scale_table[0]); 305 *type = IIO_VAL_INT_PLUS_NANO; 306 return IIO_AVAIL_LIST; 307 default: 308 return -EINVAL; 309 } 310 } 311 312 #define KX022A_DEFAULT_PERIOD_NS (20 * NSEC_PER_MSEC) 313 314 static void kx022a_reg2freq(unsigned int val, int *val1, int *val2) 315 { 316 *val1 = kx022a_accel_samp_freq_table[val & KX022A_MASK_ODR][0]; 317 *val2 = kx022a_accel_samp_freq_table[val & KX022A_MASK_ODR][1]; 318 } 319 320 static void kx022a_reg2scale(unsigned int val, unsigned int *val1, 321 unsigned int *val2) 322 { 323 val &= KX022A_MASK_GSEL; 324 val >>= KX022A_GSEL_SHIFT; 325 326 *val1 = kx022a_scale_table[val][0]; 327 *val2 = kx022a_scale_table[val][1]; 328 } 329 330 static int kx022a_turn_on_off_unlocked(struct kx022a_data *data, bool on) 331 { 332 int ret; 333 334 if (on) 335 ret = regmap_set_bits(data->regmap, KX022A_REG_CNTL, 336 KX022A_MASK_PC1); 337 else 338 ret = regmap_clear_bits(data->regmap, KX022A_REG_CNTL, 339 KX022A_MASK_PC1); 340 if (ret) 341 dev_err(data->dev, "Turn %s fail %d\n", str_on_off(on), ret); 342 343 return ret; 344 345 } 346 347 static int kx022a_turn_off_lock(struct kx022a_data *data) 348 { 349 int ret; 350 351 mutex_lock(&data->mutex); 352 ret = kx022a_turn_on_off_unlocked(data, false); 353 if (ret) 354 mutex_unlock(&data->mutex); 355 356 return ret; 357 } 358 359 static int kx022a_turn_on_unlock(struct kx022a_data *data) 360 { 361 int ret; 362 363 ret = kx022a_turn_on_off_unlocked(data, true); 364 mutex_unlock(&data->mutex); 365 366 return ret; 367 } 368 369 static int kx022a_write_raw_get_fmt(struct iio_dev *idev, 370 struct iio_chan_spec const *chan, 371 long mask) 372 { 373 switch (mask) { 374 case IIO_CHAN_INFO_SCALE: 375 return IIO_VAL_INT_PLUS_NANO; 376 case IIO_CHAN_INFO_SAMP_FREQ: 377 return IIO_VAL_INT_PLUS_MICRO; 378 default: 379 return -EINVAL; 380 } 381 } 382 383 static int kx022a_write_raw(struct iio_dev *idev, 384 struct iio_chan_spec const *chan, 385 int val, int val2, long mask) 386 { 387 struct kx022a_data *data = iio_priv(idev); 388 int ret, n; 389 390 /* 391 * We should not allow changing scale or frequency when FIFO is running 392 * as it will mess the timestamp/scale for samples existing in the 393 * buffer. If this turns out to be an issue we can later change logic 394 * to internally flush the fifo before reconfiguring so the samples in 395 * fifo keep matching the freq/scale settings. (Such setup could cause 396 * issues if users trust the watermark to be reached within known 397 * time-limit). 398 */ 399 ret = iio_device_claim_direct_mode(idev); 400 if (ret) 401 return ret; 402 403 switch (mask) { 404 case IIO_CHAN_INFO_SAMP_FREQ: 405 n = ARRAY_SIZE(kx022a_accel_samp_freq_table); 406 407 while (n--) 408 if (val == kx022a_accel_samp_freq_table[n][0] && 409 val2 == kx022a_accel_samp_freq_table[n][1]) 410 break; 411 if (n < 0) { 412 ret = -EINVAL; 413 goto unlock_out; 414 } 415 ret = kx022a_turn_off_lock(data); 416 if (ret) 417 break; 418 419 ret = regmap_update_bits(data->regmap, 420 KX022A_REG_ODCNTL, 421 KX022A_MASK_ODR, n); 422 data->odr_ns = kx022a_odrs[n]; 423 kx022a_turn_on_unlock(data); 424 break; 425 case IIO_CHAN_INFO_SCALE: 426 n = ARRAY_SIZE(kx022a_scale_table); 427 428 while (n-- > 0) 429 if (val == kx022a_scale_table[n][0] && 430 val2 == kx022a_scale_table[n][1]) 431 break; 432 if (n < 0) { 433 ret = -EINVAL; 434 goto unlock_out; 435 } 436 437 ret = kx022a_turn_off_lock(data); 438 if (ret) 439 break; 440 441 ret = regmap_update_bits(data->regmap, KX022A_REG_CNTL, 442 KX022A_MASK_GSEL, 443 n << KX022A_GSEL_SHIFT); 444 kx022a_turn_on_unlock(data); 445 break; 446 default: 447 ret = -EINVAL; 448 break; 449 } 450 451 unlock_out: 452 iio_device_release_direct_mode(idev); 453 454 return ret; 455 } 456 457 static int kx022a_fifo_set_wmi(struct kx022a_data *data) 458 { 459 u8 threshold; 460 461 threshold = data->watermark; 462 463 return regmap_update_bits(data->regmap, KX022A_REG_BUF_CNTL1, 464 KX022A_MASK_WM_TH, threshold); 465 } 466 467 static int kx022a_get_axis(struct kx022a_data *data, 468 struct iio_chan_spec const *chan, 469 int *val) 470 { 471 int ret; 472 473 ret = regmap_bulk_read(data->regmap, chan->address, &data->buffer[0], 474 sizeof(__le16)); 475 if (ret) 476 return ret; 477 478 *val = le16_to_cpu(data->buffer[0]); 479 480 return IIO_VAL_INT; 481 } 482 483 static int kx022a_read_raw(struct iio_dev *idev, 484 struct iio_chan_spec const *chan, 485 int *val, int *val2, long mask) 486 { 487 struct kx022a_data *data = iio_priv(idev); 488 unsigned int regval; 489 int ret; 490 491 switch (mask) { 492 case IIO_CHAN_INFO_RAW: 493 ret = iio_device_claim_direct_mode(idev); 494 if (ret) 495 return ret; 496 497 mutex_lock(&data->mutex); 498 ret = kx022a_get_axis(data, chan, val); 499 mutex_unlock(&data->mutex); 500 501 iio_device_release_direct_mode(idev); 502 503 return ret; 504 505 case IIO_CHAN_INFO_SAMP_FREQ: 506 ret = regmap_read(data->regmap, KX022A_REG_ODCNTL, ®val); 507 if (ret) 508 return ret; 509 510 if ((regval & KX022A_MASK_ODR) > 511 ARRAY_SIZE(kx022a_accel_samp_freq_table)) { 512 dev_err(data->dev, "Invalid ODR\n"); 513 return -EINVAL; 514 } 515 516 kx022a_reg2freq(regval, val, val2); 517 518 return IIO_VAL_INT_PLUS_MICRO; 519 520 case IIO_CHAN_INFO_SCALE: 521 ret = regmap_read(data->regmap, KX022A_REG_CNTL, ®val); 522 if (ret < 0) 523 return ret; 524 525 kx022a_reg2scale(regval, val, val2); 526 527 return IIO_VAL_INT_PLUS_NANO; 528 } 529 530 return -EINVAL; 531 }; 532 533 static int kx022a_set_watermark(struct iio_dev *idev, unsigned int val) 534 { 535 struct kx022a_data *data = iio_priv(idev); 536 537 if (val > KX022A_FIFO_LENGTH) 538 val = KX022A_FIFO_LENGTH; 539 540 mutex_lock(&data->mutex); 541 data->watermark = val; 542 mutex_unlock(&data->mutex); 543 544 return 0; 545 } 546 547 static ssize_t hwfifo_enabled_show(struct device *dev, 548 struct device_attribute *attr, 549 char *buf) 550 { 551 struct iio_dev *idev = dev_to_iio_dev(dev); 552 struct kx022a_data *data = iio_priv(idev); 553 bool state; 554 555 mutex_lock(&data->mutex); 556 state = data->state; 557 mutex_unlock(&data->mutex); 558 559 return sysfs_emit(buf, "%d\n", state); 560 } 561 562 static ssize_t hwfifo_watermark_show(struct device *dev, 563 struct device_attribute *attr, 564 char *buf) 565 { 566 struct iio_dev *idev = dev_to_iio_dev(dev); 567 struct kx022a_data *data = iio_priv(idev); 568 int wm; 569 570 mutex_lock(&data->mutex); 571 wm = data->watermark; 572 mutex_unlock(&data->mutex); 573 574 return sysfs_emit(buf, "%d\n", wm); 575 } 576 577 static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0); 578 static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0); 579 580 static const struct iio_dev_attr *kx022a_fifo_attributes[] = { 581 &iio_dev_attr_hwfifo_watermark, 582 &iio_dev_attr_hwfifo_enabled, 583 NULL 584 }; 585 586 static int kx022a_drop_fifo_contents(struct kx022a_data *data) 587 { 588 /* 589 * We must clear the old time-stamp to avoid computing the timestamps 590 * based on samples acquired when buffer was last enabled. 591 * 592 * We don't need to protect the timestamp as long as we are only 593 * called from fifo-disable where we can guarantee the sensor is not 594 * triggering interrupts and where the mutex is locked to prevent the 595 * user-space access. 596 */ 597 data->timestamp = 0; 598 599 return regmap_write(data->regmap, KX022A_REG_BUF_CLEAR, 0x0); 600 } 601 602 static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples, 603 bool irq) 604 { 605 struct kx022a_data *data = iio_priv(idev); 606 struct device *dev = regmap_get_device(data->regmap); 607 __le16 buffer[KX022A_FIFO_LENGTH * 3]; 608 uint64_t sample_period; 609 int count, fifo_bytes; 610 bool renable = false; 611 int64_t tstamp; 612 int ret, i; 613 614 ret = regmap_read(data->regmap, KX022A_REG_BUF_STATUS_1, &fifo_bytes); 615 if (ret) { 616 dev_err(dev, "Error reading buffer status\n"); 617 return ret; 618 } 619 620 /* Let's not overflow if we for some reason get bogus value from i2c */ 621 if (fifo_bytes == KX022A_FIFO_FULL_VALUE) 622 fifo_bytes = KX022A_FIFO_MAX_BYTES; 623 624 if (fifo_bytes % KX022A_FIFO_SAMPLES_SIZE_BYTES) 625 dev_warn(data->dev, "Bad FIFO alignment. Data may be corrupt\n"); 626 627 count = fifo_bytes / KX022A_FIFO_SAMPLES_SIZE_BYTES; 628 if (!count) 629 return 0; 630 631 /* 632 * If we are being called from IRQ handler we know the stored timestamp 633 * is fairly accurate for the last stored sample. Otherwise, if we are 634 * called as a result of a read operation from userspace and hence 635 * before the watermark interrupt was triggered, take a timestamp 636 * now. We can fall anywhere in between two samples so the error in this 637 * case is at most one sample period. 638 */ 639 if (!irq) { 640 /* 641 * We need to have the IRQ disabled or we risk of messing-up 642 * the timestamps. If we are ran from IRQ, then the 643 * IRQF_ONESHOT has us covered - but if we are ran by the 644 * user-space read we need to disable the IRQ to be on a safe 645 * side. We do this usng synchronous disable so that if the 646 * IRQ thread is being ran on other CPU we wait for it to be 647 * finished. 648 */ 649 disable_irq(data->irq); 650 renable = true; 651 652 data->old_timestamp = data->timestamp; 653 data->timestamp = iio_get_time_ns(idev); 654 } 655 656 /* 657 * Approximate timestamps for each of the sample based on the sampling 658 * frequency, timestamp for last sample and number of samples. 659 * 660 * We'd better not use the current bandwidth settings to compute the 661 * sample period. The real sample rate varies with the device and 662 * small variation adds when we store a large number of samples. 663 * 664 * To avoid this issue we compute the actual sample period ourselves 665 * based on the timestamp delta between the last two flush operations. 666 */ 667 if (data->old_timestamp) { 668 sample_period = data->timestamp - data->old_timestamp; 669 do_div(sample_period, count); 670 } else { 671 sample_period = data->odr_ns; 672 } 673 tstamp = data->timestamp - (count - 1) * sample_period; 674 675 if (samples && count > samples) { 676 /* 677 * Here we leave some old samples to the buffer. We need to 678 * adjust the timestamp to match the first sample in the buffer 679 * or we will miscalculate the sample_period at next round. 680 */ 681 data->timestamp -= (count - samples) * sample_period; 682 count = samples; 683 } 684 685 fifo_bytes = count * KX022A_FIFO_SAMPLES_SIZE_BYTES; 686 ret = regmap_noinc_read(data->regmap, KX022A_REG_BUF_READ, 687 &buffer[0], fifo_bytes); 688 if (ret) 689 goto renable_out; 690 691 for (i = 0; i < count; i++) { 692 __le16 *sam = &buffer[i * 3]; 693 __le16 *chs; 694 int bit; 695 696 chs = &data->scan.channels[0]; 697 for_each_set_bit(bit, idev->active_scan_mask, AXIS_MAX) 698 chs[bit] = sam[bit]; 699 700 iio_push_to_buffers_with_timestamp(idev, &data->scan, tstamp); 701 702 tstamp += sample_period; 703 } 704 705 ret = count; 706 707 renable_out: 708 if (renable) 709 enable_irq(data->irq); 710 711 return ret; 712 } 713 714 static int kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples) 715 { 716 struct kx022a_data *data = iio_priv(idev); 717 int ret; 718 719 mutex_lock(&data->mutex); 720 ret = __kx022a_fifo_flush(idev, samples, false); 721 mutex_unlock(&data->mutex); 722 723 return ret; 724 } 725 726 static const struct iio_info kx022a_info = { 727 .read_raw = &kx022a_read_raw, 728 .write_raw = &kx022a_write_raw, 729 .write_raw_get_fmt = &kx022a_write_raw_get_fmt, 730 .read_avail = &kx022a_read_avail, 731 732 .validate_trigger = iio_validate_own_trigger, 733 .hwfifo_set_watermark = kx022a_set_watermark, 734 .hwfifo_flush_to_buffer = kx022a_fifo_flush, 735 }; 736 737 static int kx022a_set_drdy_irq(struct kx022a_data *data, bool en) 738 { 739 if (en) 740 return regmap_set_bits(data->regmap, KX022A_REG_CNTL, 741 KX022A_MASK_DRDY); 742 743 return regmap_clear_bits(data->regmap, KX022A_REG_CNTL, 744 KX022A_MASK_DRDY); 745 } 746 747 static int kx022a_prepare_irq_pin(struct kx022a_data *data) 748 { 749 /* Enable IRQ1 pin. Set polarity to active low */ 750 int mask = KX022A_MASK_IEN | KX022A_MASK_IPOL | 751 KX022A_MASK_ITYP; 752 int val = KX022A_MASK_IEN | KX022A_IPOL_LOW | 753 KX022A_ITYP_LEVEL; 754 int ret; 755 756 ret = regmap_update_bits(data->regmap, data->inc_reg, mask, val); 757 if (ret) 758 return ret; 759 760 /* We enable WMI to IRQ pin only at buffer_enable */ 761 mask = KX022A_MASK_INS2_DRDY; 762 763 return regmap_set_bits(data->regmap, data->ien_reg, mask); 764 } 765 766 static int kx022a_fifo_disable(struct kx022a_data *data) 767 { 768 int ret = 0; 769 770 ret = kx022a_turn_off_lock(data); 771 if (ret) 772 return ret; 773 774 ret = regmap_clear_bits(data->regmap, data->ien_reg, KX022A_MASK_WMI); 775 if (ret) 776 goto unlock_out; 777 778 ret = regmap_clear_bits(data->regmap, KX022A_REG_BUF_CNTL2, 779 KX022A_MASK_BUF_EN); 780 if (ret) 781 goto unlock_out; 782 783 data->state &= ~KX022A_STATE_FIFO; 784 785 kx022a_drop_fifo_contents(data); 786 787 return kx022a_turn_on_unlock(data); 788 789 unlock_out: 790 mutex_unlock(&data->mutex); 791 792 return ret; 793 } 794 795 static int kx022a_buffer_predisable(struct iio_dev *idev) 796 { 797 struct kx022a_data *data = iio_priv(idev); 798 799 if (iio_device_get_current_mode(idev) == INDIO_BUFFER_TRIGGERED) 800 return 0; 801 802 return kx022a_fifo_disable(data); 803 } 804 805 static int kx022a_fifo_enable(struct kx022a_data *data) 806 { 807 int ret; 808 809 ret = kx022a_turn_off_lock(data); 810 if (ret) 811 return ret; 812 813 /* Update watermark to HW */ 814 ret = kx022a_fifo_set_wmi(data); 815 if (ret) 816 goto unlock_out; 817 818 /* Enable buffer */ 819 ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2, 820 KX022A_MASK_BUF_EN); 821 if (ret) 822 goto unlock_out; 823 824 data->state |= KX022A_STATE_FIFO; 825 ret = regmap_set_bits(data->regmap, data->ien_reg, 826 KX022A_MASK_WMI); 827 if (ret) 828 goto unlock_out; 829 830 return kx022a_turn_on_unlock(data); 831 832 unlock_out: 833 mutex_unlock(&data->mutex); 834 835 return ret; 836 } 837 838 static int kx022a_buffer_postenable(struct iio_dev *idev) 839 { 840 struct kx022a_data *data = iio_priv(idev); 841 842 /* 843 * If we use data-ready trigger, then the IRQ masks should be handled by 844 * trigger enable and the hardware buffer is not used but we just update 845 * results to the IIO fifo when data-ready triggers. 846 */ 847 if (iio_device_get_current_mode(idev) == INDIO_BUFFER_TRIGGERED) 848 return 0; 849 850 return kx022a_fifo_enable(data); 851 } 852 853 static const struct iio_buffer_setup_ops kx022a_buffer_ops = { 854 .postenable = kx022a_buffer_postenable, 855 .predisable = kx022a_buffer_predisable, 856 }; 857 858 static irqreturn_t kx022a_trigger_handler(int irq, void *p) 859 { 860 struct iio_poll_func *pf = p; 861 struct iio_dev *idev = pf->indio_dev; 862 struct kx022a_data *data = iio_priv(idev); 863 int ret; 864 865 ret = regmap_bulk_read(data->regmap, KX022A_REG_XOUT_L, data->buffer, 866 KX022A_FIFO_SAMPLES_SIZE_BYTES); 867 if (ret < 0) 868 goto err_read; 869 870 iio_push_to_buffers_with_timestamp(idev, data->buffer, data->timestamp); 871 err_read: 872 iio_trigger_notify_done(idev->trig); 873 874 return IRQ_HANDLED; 875 } 876 877 /* Get timestamps and wake the thread if we need to read data */ 878 static irqreturn_t kx022a_irq_handler(int irq, void *private) 879 { 880 struct iio_dev *idev = private; 881 struct kx022a_data *data = iio_priv(idev); 882 883 data->old_timestamp = data->timestamp; 884 data->timestamp = iio_get_time_ns(idev); 885 886 if (data->state & KX022A_STATE_FIFO || data->trigger_enabled) 887 return IRQ_WAKE_THREAD; 888 889 return IRQ_NONE; 890 } 891 892 /* 893 * WMI and data-ready IRQs are acked when results are read. If we add 894 * TILT/WAKE or other IRQs - then we may need to implement the acking 895 * (which is racy). 896 */ 897 static irqreturn_t kx022a_irq_thread_handler(int irq, void *private) 898 { 899 struct iio_dev *idev = private; 900 struct kx022a_data *data = iio_priv(idev); 901 irqreturn_t ret = IRQ_NONE; 902 903 mutex_lock(&data->mutex); 904 905 if (data->trigger_enabled) { 906 iio_trigger_poll_nested(data->trig); 907 ret = IRQ_HANDLED; 908 } 909 910 if (data->state & KX022A_STATE_FIFO) { 911 int ok; 912 913 ok = __kx022a_fifo_flush(idev, KX022A_FIFO_LENGTH, true); 914 if (ok > 0) 915 ret = IRQ_HANDLED; 916 } 917 918 mutex_unlock(&data->mutex); 919 920 return ret; 921 } 922 923 static int kx022a_trigger_set_state(struct iio_trigger *trig, 924 bool state) 925 { 926 struct kx022a_data *data = iio_trigger_get_drvdata(trig); 927 int ret = 0; 928 929 mutex_lock(&data->mutex); 930 931 if (data->trigger_enabled == state) 932 goto unlock_out; 933 934 if (data->state & KX022A_STATE_FIFO) { 935 dev_warn(data->dev, "Can't set trigger when FIFO enabled\n"); 936 ret = -EBUSY; 937 goto unlock_out; 938 } 939 940 ret = kx022a_turn_on_off_unlocked(data, false); 941 if (ret) 942 goto unlock_out; 943 944 data->trigger_enabled = state; 945 ret = kx022a_set_drdy_irq(data, state); 946 if (ret) 947 goto unlock_out; 948 949 ret = kx022a_turn_on_off_unlocked(data, true); 950 951 unlock_out: 952 mutex_unlock(&data->mutex); 953 954 return ret; 955 } 956 957 static const struct iio_trigger_ops kx022a_trigger_ops = { 958 .set_trigger_state = kx022a_trigger_set_state, 959 }; 960 961 static int kx022a_chip_init(struct kx022a_data *data) 962 { 963 int ret, val; 964 965 /* Reset the senor */ 966 ret = regmap_write(data->regmap, KX022A_REG_CNTL2, KX022A_MASK_SRST); 967 if (ret) 968 return ret; 969 970 /* 971 * I've seen I2C read failures if we poll too fast after the sensor 972 * reset. Slight delay gives I2C block the time to recover. 973 */ 974 msleep(1); 975 976 ret = regmap_read_poll_timeout(data->regmap, KX022A_REG_CNTL2, val, 977 !(val & KX022A_MASK_SRST), 978 KX022A_SOFT_RESET_WAIT_TIME_US, 979 KX022A_SOFT_RESET_TOTAL_WAIT_TIME_US); 980 if (ret) { 981 dev_err(data->dev, "Sensor reset %s\n", 982 val & KX022A_MASK_SRST ? "timeout" : "fail#"); 983 return ret; 984 } 985 986 ret = regmap_reinit_cache(data->regmap, &kx022a_regmap); 987 if (ret) { 988 dev_err(data->dev, "Failed to reinit reg cache\n"); 989 return ret; 990 } 991 992 /* set data res 16bit */ 993 ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2, 994 KX022A_MASK_BRES16); 995 if (ret) { 996 dev_err(data->dev, "Failed to set data resolution\n"); 997 return ret; 998 } 999 1000 return kx022a_prepare_irq_pin(data); 1001 } 1002 1003 int kx022a_probe_internal(struct device *dev) 1004 { 1005 static const char * const regulator_names[] = {"io-vdd", "vdd"}; 1006 struct iio_trigger *indio_trig; 1007 struct fwnode_handle *fwnode; 1008 struct kx022a_data *data; 1009 struct regmap *regmap; 1010 unsigned int chip_id; 1011 struct iio_dev *idev; 1012 int ret, irq; 1013 char *name; 1014 1015 regmap = dev_get_regmap(dev, NULL); 1016 if (!regmap) { 1017 dev_err(dev, "no regmap\n"); 1018 return -EINVAL; 1019 } 1020 1021 fwnode = dev_fwnode(dev); 1022 if (!fwnode) 1023 return -ENODEV; 1024 1025 idev = devm_iio_device_alloc(dev, sizeof(*data)); 1026 if (!idev) 1027 return -ENOMEM; 1028 1029 data = iio_priv(idev); 1030 1031 /* 1032 * VDD is the analog and digital domain voltage supply and 1033 * IO_VDD is the digital I/O voltage supply. 1034 */ 1035 ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names), 1036 regulator_names); 1037 if (ret && ret != -ENODEV) 1038 return dev_err_probe(dev, ret, "failed to enable regulator\n"); 1039 1040 ret = regmap_read(regmap, KX022A_REG_WHO, &chip_id); 1041 if (ret) 1042 return dev_err_probe(dev, ret, "Failed to access sensor\n"); 1043 1044 if (chip_id != KX022A_ID) { 1045 dev_err(dev, "unsupported device 0x%x\n", chip_id); 1046 return -EINVAL; 1047 } 1048 1049 irq = fwnode_irq_get_byname(fwnode, "INT1"); 1050 if (irq > 0) { 1051 data->inc_reg = KX022A_REG_INC1; 1052 data->ien_reg = KX022A_REG_INC4; 1053 } else { 1054 irq = fwnode_irq_get_byname(fwnode, "INT2"); 1055 if (irq < 0) 1056 return dev_err_probe(dev, irq, "No suitable IRQ\n"); 1057 1058 data->inc_reg = KX022A_REG_INC5; 1059 data->ien_reg = KX022A_REG_INC6; 1060 } 1061 1062 data->regmap = regmap; 1063 data->dev = dev; 1064 data->irq = irq; 1065 data->odr_ns = KX022A_DEFAULT_PERIOD_NS; 1066 mutex_init(&data->mutex); 1067 1068 idev->channels = kx022a_channels; 1069 idev->num_channels = ARRAY_SIZE(kx022a_channels); 1070 idev->name = "kx022-accel"; 1071 idev->info = &kx022a_info; 1072 idev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE; 1073 idev->available_scan_masks = kx022a_scan_masks; 1074 1075 /* Read the mounting matrix, if present */ 1076 ret = iio_read_mount_matrix(dev, &data->orientation); 1077 if (ret) 1078 return ret; 1079 1080 /* The sensor must be turned off for configuration */ 1081 ret = kx022a_turn_off_lock(data); 1082 if (ret) 1083 return ret; 1084 1085 ret = kx022a_chip_init(data); 1086 if (ret) { 1087 mutex_unlock(&data->mutex); 1088 return ret; 1089 } 1090 1091 ret = kx022a_turn_on_unlock(data); 1092 if (ret) 1093 return ret; 1094 1095 ret = devm_iio_triggered_buffer_setup_ext(dev, idev, 1096 &iio_pollfunc_store_time, 1097 kx022a_trigger_handler, 1098 IIO_BUFFER_DIRECTION_IN, 1099 &kx022a_buffer_ops, 1100 kx022a_fifo_attributes); 1101 1102 if (ret) 1103 return dev_err_probe(data->dev, ret, 1104 "iio_triggered_buffer_setup_ext FAIL\n"); 1105 indio_trig = devm_iio_trigger_alloc(dev, "%sdata-rdy-dev%d", idev->name, 1106 iio_device_id(idev)); 1107 if (!indio_trig) 1108 return -ENOMEM; 1109 1110 data->trig = indio_trig; 1111 1112 indio_trig->ops = &kx022a_trigger_ops; 1113 iio_trigger_set_drvdata(indio_trig, data); 1114 1115 /* 1116 * No need to check for NULL. request_threaded_irq() defaults to 1117 * dev_name() should the alloc fail. 1118 */ 1119 name = devm_kasprintf(data->dev, GFP_KERNEL, "%s-kx022a", 1120 dev_name(data->dev)); 1121 1122 ret = devm_request_threaded_irq(data->dev, irq, kx022a_irq_handler, 1123 &kx022a_irq_thread_handler, 1124 IRQF_ONESHOT, name, idev); 1125 if (ret) 1126 return dev_err_probe(data->dev, ret, "Could not request IRQ\n"); 1127 1128 1129 ret = devm_iio_trigger_register(dev, indio_trig); 1130 if (ret) 1131 return dev_err_probe(data->dev, ret, 1132 "Trigger registration failed\n"); 1133 1134 ret = devm_iio_device_register(data->dev, idev); 1135 if (ret < 0) 1136 return dev_err_probe(dev, ret, 1137 "Unable to register iio device\n"); 1138 1139 return ret; 1140 } 1141 EXPORT_SYMBOL_NS_GPL(kx022a_probe_internal, IIO_KX022A); 1142 1143 MODULE_DESCRIPTION("ROHM/Kionix KX022A accelerometer driver"); 1144 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>"); 1145 MODULE_LICENSE("GPL"); 1146