1 /* 2 * STMicroelectronics st_lsm6dsx FIFO buffer library driver 3 * 4 * LSM6DS3/LSM6DS3H/LSM6DSL/LSM6DSM/ISM330DLC: The FIFO buffer can be 5 * configured to store data from gyroscope and accelerometer. Samples are 6 * queued without any tag according to a specific pattern based on 7 * 'FIFO data sets' (6 bytes each): 8 * - 1st data set is reserved for gyroscope data 9 * - 2nd data set is reserved for accelerometer data 10 * The FIFO pattern changes depending on the ODRs and decimation factors 11 * assigned to the FIFO data sets. The first sequence of data stored in FIFO 12 * buffer contains the data of all the enabled FIFO data sets 13 * (e.g. Gx, Gy, Gz, Ax, Ay, Az), then data are repeated depending on the 14 * value of the decimation factor and ODR set for each FIFO data set. 15 * 16 * LSM6DSO/LSM6DSOX/ASM330LHH/LSM6DSR: The FIFO buffer can be configured to 17 * store data from gyroscope and accelerometer. Each sample is queued with 18 * a tag (1B) indicating data source (gyroscope, accelerometer, hw timer). 19 * 20 * FIFO supported modes: 21 * - BYPASS: FIFO disabled 22 * - CONTINUOUS: FIFO enabled. When the buffer is full, the FIFO index 23 * restarts from the beginning and the oldest sample is overwritten 24 * 25 * Copyright 2016 STMicroelectronics Inc. 26 * 27 * Lorenzo Bianconi <lorenzo.bianconi@st.com> 28 * Denis Ciocca <denis.ciocca@st.com> 29 * 30 * Licensed under the GPL-2. 31 */ 32 #include <linux/module.h> 33 #include <linux/interrupt.h> 34 #include <linux/irq.h> 35 #include <linux/iio/kfifo_buf.h> 36 #include <linux/iio/iio.h> 37 #include <linux/iio/buffer.h> 38 #include <linux/regmap.h> 39 #include <linux/bitfield.h> 40 41 #include <linux/platform_data/st_sensors_pdata.h> 42 43 #include "st_lsm6dsx.h" 44 45 #define ST_LSM6DSX_REG_HLACTIVE_ADDR 0x12 46 #define ST_LSM6DSX_REG_HLACTIVE_MASK BIT(5) 47 #define ST_LSM6DSX_REG_PP_OD_ADDR 0x12 48 #define ST_LSM6DSX_REG_PP_OD_MASK BIT(4) 49 #define ST_LSM6DSX_REG_FIFO_MODE_ADDR 0x0a 50 #define ST_LSM6DSX_FIFO_MODE_MASK GENMASK(2, 0) 51 #define ST_LSM6DSX_FIFO_ODR_MASK GENMASK(6, 3) 52 #define ST_LSM6DSX_FIFO_EMPTY_MASK BIT(12) 53 #define ST_LSM6DSX_REG_FIFO_OUTL_ADDR 0x3e 54 #define ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR 0x78 55 #define ST_LSM6DSX_REG_TS_RESET_ADDR 0x42 56 57 #define ST_LSM6DSX_MAX_FIFO_ODR_VAL 0x08 58 59 #define ST_LSM6DSX_TS_SENSITIVITY 25000UL /* 25us */ 60 #define ST_LSM6DSX_TS_RESET_VAL 0xaa 61 62 struct st_lsm6dsx_decimator_entry { 63 u8 decimator; 64 u8 val; 65 }; 66 67 enum st_lsm6dsx_fifo_tag { 68 ST_LSM6DSX_GYRO_TAG = 0x01, 69 ST_LSM6DSX_ACC_TAG = 0x02, 70 ST_LSM6DSX_TS_TAG = 0x04, 71 ST_LSM6DSX_EXT0_TAG = 0x0f, 72 ST_LSM6DSX_EXT1_TAG = 0x10, 73 ST_LSM6DSX_EXT2_TAG = 0x11, 74 }; 75 76 static const 77 struct st_lsm6dsx_decimator_entry st_lsm6dsx_decimator_table[] = { 78 { 0, 0x0 }, 79 { 1, 0x1 }, 80 { 2, 0x2 }, 81 { 3, 0x3 }, 82 { 4, 0x4 }, 83 { 8, 0x5 }, 84 { 16, 0x6 }, 85 { 32, 0x7 }, 86 }; 87 88 static int st_lsm6dsx_get_decimator_val(u8 val) 89 { 90 const int max_size = ARRAY_SIZE(st_lsm6dsx_decimator_table); 91 int i; 92 93 for (i = 0; i < max_size; i++) 94 if (st_lsm6dsx_decimator_table[i].decimator == val) 95 break; 96 97 return i == max_size ? 0 : st_lsm6dsx_decimator_table[i].val; 98 } 99 100 static void st_lsm6dsx_get_max_min_odr(struct st_lsm6dsx_hw *hw, 101 u16 *max_odr, u16 *min_odr) 102 { 103 struct st_lsm6dsx_sensor *sensor; 104 int i; 105 106 *max_odr = 0, *min_odr = ~0; 107 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { 108 if (!hw->iio_devs[i]) 109 continue; 110 111 sensor = iio_priv(hw->iio_devs[i]); 112 113 if (!(hw->enable_mask & BIT(sensor->id))) 114 continue; 115 116 *max_odr = max_t(u16, *max_odr, sensor->odr); 117 *min_odr = min_t(u16, *min_odr, sensor->odr); 118 } 119 } 120 121 static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw) 122 { 123 u16 max_odr, min_odr, sip = 0, ts_sip = 0; 124 const struct st_lsm6dsx_reg *ts_dec_reg; 125 struct st_lsm6dsx_sensor *sensor; 126 int err = 0, i; 127 u8 data; 128 129 st_lsm6dsx_get_max_min_odr(hw, &max_odr, &min_odr); 130 131 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { 132 const struct st_lsm6dsx_reg *dec_reg; 133 134 if (!hw->iio_devs[i]) 135 continue; 136 137 sensor = iio_priv(hw->iio_devs[i]); 138 /* update fifo decimators and sample in pattern */ 139 if (hw->enable_mask & BIT(sensor->id)) { 140 sensor->sip = sensor->odr / min_odr; 141 sensor->decimator = max_odr / sensor->odr; 142 data = st_lsm6dsx_get_decimator_val(sensor->decimator); 143 } else { 144 sensor->sip = 0; 145 sensor->decimator = 0; 146 data = 0; 147 } 148 ts_sip = max_t(u16, ts_sip, sensor->sip); 149 150 dec_reg = &hw->settings->decimator[sensor->id]; 151 if (dec_reg->addr) { 152 int val = ST_LSM6DSX_SHIFT_VAL(data, dec_reg->mask); 153 154 err = st_lsm6dsx_update_bits_locked(hw, dec_reg->addr, 155 dec_reg->mask, 156 val); 157 if (err < 0) 158 return err; 159 } 160 sip += sensor->sip; 161 } 162 hw->sip = sip + ts_sip; 163 hw->ts_sip = ts_sip; 164 165 /* 166 * update hw ts decimator if necessary. Decimator for hw timestamp 167 * is always 1 or 0 in order to have a ts sample for each data 168 * sample in FIFO 169 */ 170 ts_dec_reg = &hw->settings->ts_settings.decimator; 171 if (ts_dec_reg->addr) { 172 int val, ts_dec = !!hw->ts_sip; 173 174 val = ST_LSM6DSX_SHIFT_VAL(ts_dec, ts_dec_reg->mask); 175 err = st_lsm6dsx_update_bits_locked(hw, ts_dec_reg->addr, 176 ts_dec_reg->mask, val); 177 } 178 return err; 179 } 180 181 int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw, 182 enum st_lsm6dsx_fifo_mode fifo_mode) 183 { 184 unsigned int data; 185 int err; 186 187 data = FIELD_PREP(ST_LSM6DSX_FIFO_MODE_MASK, fifo_mode); 188 err = st_lsm6dsx_update_bits_locked(hw, ST_LSM6DSX_REG_FIFO_MODE_ADDR, 189 ST_LSM6DSX_FIFO_MODE_MASK, data); 190 if (err < 0) 191 return err; 192 193 hw->fifo_mode = fifo_mode; 194 195 return 0; 196 } 197 198 static int st_lsm6dsx_set_fifo_odr(struct st_lsm6dsx_sensor *sensor, 199 bool enable) 200 { 201 struct st_lsm6dsx_hw *hw = sensor->hw; 202 const struct st_lsm6dsx_reg *batch_reg; 203 u8 data; 204 205 batch_reg = &hw->settings->batch[sensor->id]; 206 if (batch_reg->addr) { 207 int val; 208 209 if (enable) { 210 int err; 211 212 err = st_lsm6dsx_check_odr(sensor, sensor->odr, 213 &data); 214 if (err < 0) 215 return err; 216 } else { 217 data = 0; 218 } 219 val = ST_LSM6DSX_SHIFT_VAL(data, batch_reg->mask); 220 return st_lsm6dsx_update_bits_locked(hw, batch_reg->addr, 221 batch_reg->mask, val); 222 } else { 223 data = hw->enable_mask ? ST_LSM6DSX_MAX_FIFO_ODR_VAL : 0; 224 return st_lsm6dsx_update_bits_locked(hw, 225 ST_LSM6DSX_REG_FIFO_MODE_ADDR, 226 ST_LSM6DSX_FIFO_ODR_MASK, 227 FIELD_PREP(ST_LSM6DSX_FIFO_ODR_MASK, 228 data)); 229 } 230 } 231 232 int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor, u16 watermark) 233 { 234 u16 fifo_watermark = ~0, cur_watermark, fifo_th_mask; 235 struct st_lsm6dsx_hw *hw = sensor->hw; 236 struct st_lsm6dsx_sensor *cur_sensor; 237 int i, err, data; 238 __le16 wdata; 239 240 if (!hw->sip) 241 return 0; 242 243 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { 244 if (!hw->iio_devs[i]) 245 continue; 246 247 cur_sensor = iio_priv(hw->iio_devs[i]); 248 249 if (!(hw->enable_mask & BIT(cur_sensor->id))) 250 continue; 251 252 cur_watermark = (cur_sensor == sensor) ? watermark 253 : cur_sensor->watermark; 254 255 fifo_watermark = min_t(u16, fifo_watermark, cur_watermark); 256 } 257 258 fifo_watermark = max_t(u16, fifo_watermark, hw->sip); 259 fifo_watermark = (fifo_watermark / hw->sip) * hw->sip; 260 fifo_watermark = fifo_watermark * hw->settings->fifo_ops.th_wl; 261 262 mutex_lock(&hw->page_lock); 263 err = regmap_read(hw->regmap, hw->settings->fifo_ops.fifo_th.addr + 1, 264 &data); 265 if (err < 0) 266 goto out; 267 268 fifo_th_mask = hw->settings->fifo_ops.fifo_th.mask; 269 fifo_watermark = ((data << 8) & ~fifo_th_mask) | 270 (fifo_watermark & fifo_th_mask); 271 272 wdata = cpu_to_le16(fifo_watermark); 273 err = regmap_bulk_write(hw->regmap, 274 hw->settings->fifo_ops.fifo_th.addr, 275 &wdata, sizeof(wdata)); 276 out: 277 mutex_unlock(&hw->page_lock); 278 return err; 279 } 280 281 static int st_lsm6dsx_reset_hw_ts(struct st_lsm6dsx_hw *hw) 282 { 283 struct st_lsm6dsx_sensor *sensor; 284 int i, err; 285 286 /* reset hw ts counter */ 287 err = st_lsm6dsx_write_locked(hw, ST_LSM6DSX_REG_TS_RESET_ADDR, 288 ST_LSM6DSX_TS_RESET_VAL); 289 if (err < 0) 290 return err; 291 292 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { 293 if (!hw->iio_devs[i]) 294 continue; 295 296 sensor = iio_priv(hw->iio_devs[i]); 297 /* 298 * store enable buffer timestamp as reference for 299 * hw timestamp 300 */ 301 sensor->ts_ref = iio_get_time_ns(hw->iio_devs[i]); 302 } 303 return 0; 304 } 305 306 /* 307 * Set max bulk read to ST_LSM6DSX_MAX_WORD_LEN/ST_LSM6DSX_MAX_TAGGED_WORD_LEN 308 * in order to avoid a kmalloc for each bus access 309 */ 310 static inline int st_lsm6dsx_read_block(struct st_lsm6dsx_hw *hw, u8 addr, 311 u8 *data, unsigned int data_len, 312 unsigned int max_word_len) 313 { 314 unsigned int word_len, read_len = 0; 315 int err; 316 317 while (read_len < data_len) { 318 word_len = min_t(unsigned int, data_len - read_len, 319 max_word_len); 320 err = st_lsm6dsx_read_locked(hw, addr, data + read_len, 321 word_len); 322 if (err < 0) 323 return err; 324 read_len += word_len; 325 } 326 return 0; 327 } 328 329 #define ST_LSM6DSX_IIO_BUFF_SIZE (ALIGN(ST_LSM6DSX_SAMPLE_SIZE, \ 330 sizeof(s64)) + sizeof(s64)) 331 /** 332 * st_lsm6dsx_read_fifo() - hw FIFO read routine 333 * @hw: Pointer to instance of struct st_lsm6dsx_hw. 334 * 335 * Read samples from the hw FIFO and push them to IIO buffers. 336 * 337 * Return: Number of bytes read from the FIFO 338 */ 339 int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw) 340 { 341 u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE; 342 u16 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask; 343 int err, acc_sip, gyro_sip, ts_sip, read_len, offset; 344 struct st_lsm6dsx_sensor *acc_sensor, *gyro_sensor; 345 u8 gyro_buff[ST_LSM6DSX_IIO_BUFF_SIZE]; 346 u8 acc_buff[ST_LSM6DSX_IIO_BUFF_SIZE]; 347 bool reset_ts = false; 348 __le16 fifo_status; 349 s64 ts = 0; 350 351 err = st_lsm6dsx_read_locked(hw, 352 hw->settings->fifo_ops.fifo_diff.addr, 353 &fifo_status, sizeof(fifo_status)); 354 if (err < 0) { 355 dev_err(hw->dev, "failed to read fifo status (err=%d)\n", 356 err); 357 return err; 358 } 359 360 if (fifo_status & cpu_to_le16(ST_LSM6DSX_FIFO_EMPTY_MASK)) 361 return 0; 362 363 fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) * 364 ST_LSM6DSX_CHAN_SIZE; 365 fifo_len = (fifo_len / pattern_len) * pattern_len; 366 367 acc_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]); 368 gyro_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_GYRO]); 369 370 for (read_len = 0; read_len < fifo_len; read_len += pattern_len) { 371 err = st_lsm6dsx_read_block(hw, ST_LSM6DSX_REG_FIFO_OUTL_ADDR, 372 hw->buff, pattern_len, 373 ST_LSM6DSX_MAX_WORD_LEN); 374 if (err < 0) { 375 dev_err(hw->dev, 376 "failed to read pattern from fifo (err=%d)\n", 377 err); 378 return err; 379 } 380 381 /* 382 * Data are written to the FIFO with a specific pattern 383 * depending on the configured ODRs. The first sequence of data 384 * stored in FIFO contains the data of all enabled sensors 385 * (e.g. Gx, Gy, Gz, Ax, Ay, Az, Ts), then data are repeated 386 * depending on the value of the decimation factor set for each 387 * sensor. 388 * 389 * Supposing the FIFO is storing data from gyroscope and 390 * accelerometer at different ODRs: 391 * - gyroscope ODR = 208Hz, accelerometer ODR = 104Hz 392 * Since the gyroscope ODR is twice the accelerometer one, the 393 * following pattern is repeated every 9 samples: 394 * - Gx, Gy, Gz, Ax, Ay, Az, Ts, Gx, Gy, Gz, Ts, Gx, .. 395 */ 396 gyro_sip = gyro_sensor->sip; 397 acc_sip = acc_sensor->sip; 398 ts_sip = hw->ts_sip; 399 offset = 0; 400 401 while (acc_sip > 0 || gyro_sip > 0) { 402 if (gyro_sip > 0) { 403 memcpy(gyro_buff, &hw->buff[offset], 404 ST_LSM6DSX_SAMPLE_SIZE); 405 offset += ST_LSM6DSX_SAMPLE_SIZE; 406 } 407 if (acc_sip > 0) { 408 memcpy(acc_buff, &hw->buff[offset], 409 ST_LSM6DSX_SAMPLE_SIZE); 410 offset += ST_LSM6DSX_SAMPLE_SIZE; 411 } 412 413 if (ts_sip-- > 0) { 414 u8 data[ST_LSM6DSX_SAMPLE_SIZE]; 415 416 memcpy(data, &hw->buff[offset], sizeof(data)); 417 /* 418 * hw timestamp is 3B long and it is stored 419 * in FIFO using 6B as 4th FIFO data set 420 * according to this schema: 421 * B0 = ts[15:8], B1 = ts[23:16], B3 = ts[7:0] 422 */ 423 ts = data[1] << 16 | data[0] << 8 | data[3]; 424 /* 425 * check if hw timestamp engine is going to 426 * reset (the sensor generates an interrupt 427 * to signal the hw timestamp will reset in 428 * 1.638s) 429 */ 430 if (!reset_ts && ts >= 0xff0000) 431 reset_ts = true; 432 ts *= ST_LSM6DSX_TS_SENSITIVITY; 433 434 offset += ST_LSM6DSX_SAMPLE_SIZE; 435 } 436 437 if (gyro_sip-- > 0) 438 iio_push_to_buffers_with_timestamp( 439 hw->iio_devs[ST_LSM6DSX_ID_GYRO], 440 gyro_buff, gyro_sensor->ts_ref + ts); 441 if (acc_sip-- > 0) 442 iio_push_to_buffers_with_timestamp( 443 hw->iio_devs[ST_LSM6DSX_ID_ACC], 444 acc_buff, acc_sensor->ts_ref + ts); 445 } 446 } 447 448 if (unlikely(reset_ts)) { 449 err = st_lsm6dsx_reset_hw_ts(hw); 450 if (err < 0) { 451 dev_err(hw->dev, "failed to reset hw ts (err=%d)\n", 452 err); 453 return err; 454 } 455 } 456 return read_len; 457 } 458 459 static int 460 st_lsm6dsx_push_tagged_data(struct st_lsm6dsx_hw *hw, u8 tag, 461 u8 *data, s64 ts) 462 { 463 struct st_lsm6dsx_sensor *sensor; 464 struct iio_dev *iio_dev; 465 466 /* 467 * EXT_TAG are managed in FIFO fashion so ST_LSM6DSX_EXT0_TAG 468 * corresponds to the first enabled channel, ST_LSM6DSX_EXT1_TAG 469 * to the second one and ST_LSM6DSX_EXT2_TAG to the last enabled 470 * channel 471 */ 472 switch (tag) { 473 case ST_LSM6DSX_GYRO_TAG: 474 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_GYRO]; 475 break; 476 case ST_LSM6DSX_ACC_TAG: 477 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_ACC]; 478 break; 479 case ST_LSM6DSX_EXT0_TAG: 480 if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0)) 481 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT0]; 482 else if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1)) 483 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1]; 484 else 485 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; 486 break; 487 case ST_LSM6DSX_EXT1_TAG: 488 if ((hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0)) && 489 (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1))) 490 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1]; 491 else 492 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; 493 break; 494 case ST_LSM6DSX_EXT2_TAG: 495 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; 496 break; 497 default: 498 return -EINVAL; 499 } 500 501 sensor = iio_priv(iio_dev); 502 iio_push_to_buffers_with_timestamp(iio_dev, data, 503 ts + sensor->ts_ref); 504 505 return 0; 506 } 507 508 /** 509 * st_lsm6dsx_read_tagged_fifo() - tagged hw FIFO read routine 510 * @hw: Pointer to instance of struct st_lsm6dsx_hw. 511 * 512 * Read samples from the hw FIFO and push them to IIO buffers. 513 * 514 * Return: Number of bytes read from the FIFO 515 */ 516 int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw) 517 { 518 u16 pattern_len = hw->sip * ST_LSM6DSX_TAGGED_SAMPLE_SIZE; 519 u16 fifo_len, fifo_diff_mask; 520 u8 iio_buff[ST_LSM6DSX_IIO_BUFF_SIZE], tag; 521 bool reset_ts = false; 522 int i, err, read_len; 523 __le16 fifo_status; 524 s64 ts = 0; 525 526 err = st_lsm6dsx_read_locked(hw, 527 hw->settings->fifo_ops.fifo_diff.addr, 528 &fifo_status, sizeof(fifo_status)); 529 if (err < 0) { 530 dev_err(hw->dev, "failed to read fifo status (err=%d)\n", 531 err); 532 return err; 533 } 534 535 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask; 536 fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) * 537 ST_LSM6DSX_TAGGED_SAMPLE_SIZE; 538 if (!fifo_len) 539 return 0; 540 541 for (read_len = 0; read_len < fifo_len; read_len += pattern_len) { 542 err = st_lsm6dsx_read_block(hw, 543 ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR, 544 hw->buff, pattern_len, 545 ST_LSM6DSX_MAX_TAGGED_WORD_LEN); 546 if (err < 0) { 547 dev_err(hw->dev, 548 "failed to read pattern from fifo (err=%d)\n", 549 err); 550 return err; 551 } 552 553 for (i = 0; i < pattern_len; 554 i += ST_LSM6DSX_TAGGED_SAMPLE_SIZE) { 555 memcpy(iio_buff, &hw->buff[i + ST_LSM6DSX_TAG_SIZE], 556 ST_LSM6DSX_SAMPLE_SIZE); 557 558 tag = hw->buff[i] >> 3; 559 if (tag == ST_LSM6DSX_TS_TAG) { 560 /* 561 * hw timestamp is 4B long and it is stored 562 * in FIFO according to this schema: 563 * B0 = ts[7:0], B1 = ts[15:8], B2 = ts[23:16], 564 * B3 = ts[31:24] 565 */ 566 ts = le32_to_cpu(*((__le32 *)iio_buff)); 567 /* 568 * check if hw timestamp engine is going to 569 * reset (the sensor generates an interrupt 570 * to signal the hw timestamp will reset in 571 * 1.638s) 572 */ 573 if (!reset_ts && ts >= 0xffff0000) 574 reset_ts = true; 575 ts *= ST_LSM6DSX_TS_SENSITIVITY; 576 } else { 577 st_lsm6dsx_push_tagged_data(hw, tag, iio_buff, 578 ts); 579 } 580 } 581 } 582 583 if (unlikely(reset_ts)) { 584 err = st_lsm6dsx_reset_hw_ts(hw); 585 if (err < 0) 586 return err; 587 } 588 return read_len; 589 } 590 591 int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw) 592 { 593 int err; 594 595 mutex_lock(&hw->fifo_lock); 596 597 hw->settings->fifo_ops.read_fifo(hw); 598 err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS); 599 600 mutex_unlock(&hw->fifo_lock); 601 602 return err; 603 } 604 605 static int st_lsm6dsx_update_fifo(struct iio_dev *iio_dev, bool enable) 606 { 607 struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev); 608 struct st_lsm6dsx_hw *hw = sensor->hw; 609 int err; 610 611 mutex_lock(&hw->conf_lock); 612 613 if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) { 614 err = st_lsm6dsx_flush_fifo(hw); 615 if (err < 0) 616 goto out; 617 } 618 619 if (sensor->id == ST_LSM6DSX_ID_EXT0 || 620 sensor->id == ST_LSM6DSX_ID_EXT1 || 621 sensor->id == ST_LSM6DSX_ID_EXT2) { 622 err = st_lsm6dsx_shub_set_enable(sensor, enable); 623 if (err < 0) 624 goto out; 625 } else { 626 err = st_lsm6dsx_sensor_set_enable(sensor, enable); 627 if (err < 0) 628 goto out; 629 630 err = st_lsm6dsx_set_fifo_odr(sensor, enable); 631 if (err < 0) 632 goto out; 633 } 634 635 err = st_lsm6dsx_update_decimators(hw); 636 if (err < 0) 637 goto out; 638 639 err = st_lsm6dsx_update_watermark(sensor, sensor->watermark); 640 if (err < 0) 641 goto out; 642 643 if (hw->enable_mask) { 644 /* reset hw ts counter */ 645 err = st_lsm6dsx_reset_hw_ts(hw); 646 if (err < 0) 647 goto out; 648 649 err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_CONT); 650 } 651 652 out: 653 mutex_unlock(&hw->conf_lock); 654 655 return err; 656 } 657 658 static irqreturn_t st_lsm6dsx_handler_irq(int irq, void *private) 659 { 660 struct st_lsm6dsx_hw *hw = private; 661 662 return hw->sip > 0 ? IRQ_WAKE_THREAD : IRQ_NONE; 663 } 664 665 static irqreturn_t st_lsm6dsx_handler_thread(int irq, void *private) 666 { 667 struct st_lsm6dsx_hw *hw = private; 668 int count; 669 670 mutex_lock(&hw->fifo_lock); 671 count = hw->settings->fifo_ops.read_fifo(hw); 672 mutex_unlock(&hw->fifo_lock); 673 674 return !count ? IRQ_NONE : IRQ_HANDLED; 675 } 676 677 static int st_lsm6dsx_buffer_preenable(struct iio_dev *iio_dev) 678 { 679 return st_lsm6dsx_update_fifo(iio_dev, true); 680 } 681 682 static int st_lsm6dsx_buffer_postdisable(struct iio_dev *iio_dev) 683 { 684 return st_lsm6dsx_update_fifo(iio_dev, false); 685 } 686 687 static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = { 688 .preenable = st_lsm6dsx_buffer_preenable, 689 .postdisable = st_lsm6dsx_buffer_postdisable, 690 }; 691 692 int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw) 693 { 694 struct device_node *np = hw->dev->of_node; 695 struct st_sensors_platform_data *pdata; 696 struct iio_buffer *buffer; 697 unsigned long irq_type; 698 bool irq_active_low; 699 int i, err; 700 701 irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq)); 702 703 switch (irq_type) { 704 case IRQF_TRIGGER_HIGH: 705 case IRQF_TRIGGER_RISING: 706 irq_active_low = false; 707 break; 708 case IRQF_TRIGGER_LOW: 709 case IRQF_TRIGGER_FALLING: 710 irq_active_low = true; 711 break; 712 default: 713 dev_info(hw->dev, "mode %lx unsupported\n", irq_type); 714 return -EINVAL; 715 } 716 717 err = regmap_update_bits(hw->regmap, ST_LSM6DSX_REG_HLACTIVE_ADDR, 718 ST_LSM6DSX_REG_HLACTIVE_MASK, 719 FIELD_PREP(ST_LSM6DSX_REG_HLACTIVE_MASK, 720 irq_active_low)); 721 if (err < 0) 722 return err; 723 724 pdata = (struct st_sensors_platform_data *)hw->dev->platform_data; 725 if ((np && of_property_read_bool(np, "drive-open-drain")) || 726 (pdata && pdata->open_drain)) { 727 err = regmap_update_bits(hw->regmap, ST_LSM6DSX_REG_PP_OD_ADDR, 728 ST_LSM6DSX_REG_PP_OD_MASK, 729 FIELD_PREP(ST_LSM6DSX_REG_PP_OD_MASK, 730 1)); 731 if (err < 0) 732 return err; 733 734 irq_type |= IRQF_SHARED; 735 } 736 737 err = devm_request_threaded_irq(hw->dev, hw->irq, 738 st_lsm6dsx_handler_irq, 739 st_lsm6dsx_handler_thread, 740 irq_type | IRQF_ONESHOT, 741 "lsm6dsx", hw); 742 if (err) { 743 dev_err(hw->dev, "failed to request trigger irq %d\n", 744 hw->irq); 745 return err; 746 } 747 748 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { 749 if (!hw->iio_devs[i]) 750 continue; 751 752 buffer = devm_iio_kfifo_allocate(hw->dev); 753 if (!buffer) 754 return -ENOMEM; 755 756 iio_device_attach_buffer(hw->iio_devs[i], buffer); 757 hw->iio_devs[i]->modes |= INDIO_BUFFER_SOFTWARE; 758 hw->iio_devs[i]->setup_ops = &st_lsm6dsx_buffer_ops; 759 } 760 761 return 0; 762 } 763