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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * STMicroelectronics st_lsm6dsx FIFO buffer library driver4 *5 * Pattern FIFO:6 * The FIFO buffer can be configured to store data from gyroscope and7 * accelerometer. Samples are queued without any tag according to a8 * specific pattern based on 'FIFO data sets' (6 bytes each):9 * - 1st data set is reserved for gyroscope data10 * - 2nd data set is reserved for accelerometer data11 * The FIFO pattern changes depending on the ODRs and decimation factors12 * assigned to the FIFO data sets. The first sequence of data stored in FIFO13 * buffer contains the data of all the enabled FIFO data sets14 * (e.g. Gx, Gy, Gz, Ax, Ay, Az), then data are repeated depending on the15 * value of the decimation factor and ODR set for each FIFO data set.16 *17 * Supported devices:18 * - ISM330DLC19 * - LSM6DS320 * - LSM6DS3H21 * - LSM6DS3TR-C22 * - LSM6DSL23 * - LSM6DSM24 *25 * Tagged FIFO:26 * The FIFO buffer can be configured to store data from gyroscope and27 * accelerometer. Each sample is queued with a tag (1B) indicating data28 * source (gyroscope, accelerometer, hw timer).29 *30 * Supported devices:31 * - ASM330LHB32 * - ASM330LHH33 * - ASM330LHHX34 * - ASM330LHHXG135 * - ISM330DHCX36 * - LSM6DSO37 * - LSM6DSOP38 * - LSM6DSOX39 * - LSM6DSR40 * - LSM6DSRX41 * - LSM6DST42 * - LSM6DSTX43 * - LSM6DSV44 *45 * FIFO supported modes:46 * - BYPASS: FIFO disabled47 * - CONTINUOUS: FIFO enabled. When the buffer is full, the FIFO index48 * restarts from the beginning and the oldest sample is overwritten49 *50 * Copyright 2016 STMicroelectronics Inc.51 *52 * Lorenzo Bianconi <lorenzo.bianconi@st.com>53 * Denis Ciocca <denis.ciocca@st.com>54 */55#include <linux/module.h>56#include <linux/iio/kfifo_buf.h>57#include <linux/iio/iio.h>58#include <linux/iio/buffer.h>59#include <linux/regmap.h>60#include <linux/bitfield.h>61 62#include <linux/platform_data/st_sensors_pdata.h>63 64#include "st_lsm6dsx.h"65 66#define ST_LSM6DSX_REG_FIFO_MODE_ADDR 0x0a67#define ST_LSM6DSX_FIFO_MODE_MASK GENMASK(2, 0)68#define ST_LSM6DSX_FIFO_ODR_MASK GENMASK(6, 3)69#define ST_LSM6DSX_FIFO_EMPTY_MASK BIT(12)70#define ST_LSM6DSX_REG_FIFO_OUTL_ADDR 0x3e71#define ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR 0x7872#define ST_LSM6DSX_REG_TS_RESET_ADDR 0x4273 74#define ST_LSM6DSX_MAX_FIFO_ODR_VAL 0x0875 76#define ST_LSM6DSX_TS_RESET_VAL 0xaa77 78struct st_lsm6dsx_decimator_entry {79 u8 decimator;80 u8 val;81};82 83enum st_lsm6dsx_fifo_tag {84 ST_LSM6DSX_GYRO_TAG = 0x01,85 ST_LSM6DSX_ACC_TAG = 0x02,86 ST_LSM6DSX_TS_TAG = 0x04,87 ST_LSM6DSX_EXT0_TAG = 0x0f,88 ST_LSM6DSX_EXT1_TAG = 0x10,89 ST_LSM6DSX_EXT2_TAG = 0x11,90};91 92static const93struct st_lsm6dsx_decimator_entry st_lsm6dsx_decimator_table[] = {94 { 0, 0x0 },95 { 1, 0x1 },96 { 2, 0x2 },97 { 3, 0x3 },98 { 4, 0x4 },99 { 8, 0x5 },100 { 16, 0x6 },101 { 32, 0x7 },102};103 104static int105st_lsm6dsx_get_decimator_val(struct st_lsm6dsx_sensor *sensor, u32 max_odr)106{107 const int max_size = ARRAY_SIZE(st_lsm6dsx_decimator_table);108 u32 decimator = max_odr / sensor->odr;109 int i;110 111 if (decimator > 1)112 decimator = round_down(decimator, 2);113 114 for (i = 0; i < max_size; i++) {115 if (st_lsm6dsx_decimator_table[i].decimator == decimator)116 break;117 }118 119 sensor->decimator = decimator;120 return i == max_size ? 0 : st_lsm6dsx_decimator_table[i].val;121}122 123static void st_lsm6dsx_get_max_min_odr(struct st_lsm6dsx_hw *hw,124 u32 *max_odr, u32 *min_odr)125{126 struct st_lsm6dsx_sensor *sensor;127 int i;128 129 *max_odr = 0, *min_odr = ~0;130 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {131 if (!hw->iio_devs[i])132 continue;133 134 sensor = iio_priv(hw->iio_devs[i]);135 136 if (!(hw->enable_mask & BIT(sensor->id)))137 continue;138 139 *max_odr = max_t(u32, *max_odr, sensor->odr);140 *min_odr = min_t(u32, *min_odr, sensor->odr);141 }142}143 144static u8 st_lsm6dsx_get_sip(struct st_lsm6dsx_sensor *sensor, u32 min_odr)145{146 u8 sip = sensor->odr / min_odr;147 148 return sip > 1 ? round_down(sip, 2) : sip;149}150 151static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)152{153 const struct st_lsm6dsx_reg *ts_dec_reg;154 struct st_lsm6dsx_sensor *sensor;155 u16 sip = 0, ts_sip = 0;156 u32 max_odr, min_odr;157 int err = 0, i;158 u8 data;159 160 st_lsm6dsx_get_max_min_odr(hw, &max_odr, &min_odr);161 162 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {163 const struct st_lsm6dsx_reg *dec_reg;164 165 if (!hw->iio_devs[i])166 continue;167 168 sensor = iio_priv(hw->iio_devs[i]);169 /* update fifo decimators and sample in pattern */170 if (hw->enable_mask & BIT(sensor->id)) {171 sensor->sip = st_lsm6dsx_get_sip(sensor, min_odr);172 data = st_lsm6dsx_get_decimator_val(sensor, max_odr);173 } else {174 sensor->sip = 0;175 data = 0;176 }177 ts_sip = max_t(u16, ts_sip, sensor->sip);178 179 dec_reg = &hw->settings->decimator[sensor->id];180 if (dec_reg->addr) {181 int val = ST_LSM6DSX_SHIFT_VAL(data, dec_reg->mask);182 183 err = st_lsm6dsx_update_bits_locked(hw, dec_reg->addr,184 dec_reg->mask,185 val);186 if (err < 0)187 return err;188 }189 sip += sensor->sip;190 }191 hw->sip = sip + ts_sip;192 hw->ts_sip = ts_sip;193 194 /*195 * update hw ts decimator if necessary. Decimator for hw timestamp196 * is always 1 or 0 in order to have a ts sample for each data197 * sample in FIFO198 */199 ts_dec_reg = &hw->settings->ts_settings.decimator;200 if (ts_dec_reg->addr) {201 int val, ts_dec = !!hw->ts_sip;202 203 val = ST_LSM6DSX_SHIFT_VAL(ts_dec, ts_dec_reg->mask);204 err = st_lsm6dsx_update_bits_locked(hw, ts_dec_reg->addr,205 ts_dec_reg->mask, val);206 }207 return err;208}209 210static int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw,211 enum st_lsm6dsx_fifo_mode fifo_mode)212{213 unsigned int data;214 215 data = FIELD_PREP(ST_LSM6DSX_FIFO_MODE_MASK, fifo_mode);216 return st_lsm6dsx_update_bits_locked(hw, ST_LSM6DSX_REG_FIFO_MODE_ADDR,217 ST_LSM6DSX_FIFO_MODE_MASK, data);218}219 220static int st_lsm6dsx_set_fifo_odr(struct st_lsm6dsx_sensor *sensor,221 bool enable)222{223 struct st_lsm6dsx_hw *hw = sensor->hw;224 const struct st_lsm6dsx_reg *batch_reg;225 u8 data;226 227 batch_reg = &hw->settings->batch[sensor->id];228 if (batch_reg->addr) {229 int val;230 231 if (enable) {232 int err;233 234 err = st_lsm6dsx_check_odr(sensor, sensor->odr,235 &data);236 if (err < 0)237 return err;238 } else {239 data = 0;240 }241 val = ST_LSM6DSX_SHIFT_VAL(data, batch_reg->mask);242 return st_lsm6dsx_update_bits_locked(hw, batch_reg->addr,243 batch_reg->mask, val);244 } else {245 data = hw->enable_mask ? ST_LSM6DSX_MAX_FIFO_ODR_VAL : 0;246 return st_lsm6dsx_update_bits_locked(hw,247 ST_LSM6DSX_REG_FIFO_MODE_ADDR,248 ST_LSM6DSX_FIFO_ODR_MASK,249 FIELD_PREP(ST_LSM6DSX_FIFO_ODR_MASK,250 data));251 }252}253 254int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor, u16 watermark)255{256 u16 fifo_watermark = ~0, cur_watermark, fifo_th_mask;257 struct st_lsm6dsx_hw *hw = sensor->hw;258 struct st_lsm6dsx_sensor *cur_sensor;259 int i, err, data;260 __le16 wdata;261 262 if (!hw->sip)263 return 0;264 265 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {266 if (!hw->iio_devs[i])267 continue;268 269 cur_sensor = iio_priv(hw->iio_devs[i]);270 271 if (!(hw->enable_mask & BIT(cur_sensor->id)))272 continue;273 274 cur_watermark = (cur_sensor == sensor) ? watermark275 : cur_sensor->watermark;276 277 fifo_watermark = min_t(u16, fifo_watermark, cur_watermark);278 }279 280 fifo_watermark = max_t(u16, fifo_watermark, hw->sip);281 fifo_watermark = (fifo_watermark / hw->sip) * hw->sip;282 fifo_watermark = fifo_watermark * hw->settings->fifo_ops.th_wl;283 284 mutex_lock(&hw->page_lock);285 err = regmap_read(hw->regmap, hw->settings->fifo_ops.fifo_th.addr + 1,286 &data);287 if (err < 0)288 goto out;289 290 fifo_th_mask = hw->settings->fifo_ops.fifo_th.mask;291 fifo_watermark = ((data << 8) & ~fifo_th_mask) |292 (fifo_watermark & fifo_th_mask);293 294 wdata = cpu_to_le16(fifo_watermark);295 err = regmap_bulk_write(hw->regmap,296 hw->settings->fifo_ops.fifo_th.addr,297 &wdata, sizeof(wdata));298out:299 mutex_unlock(&hw->page_lock);300 return err;301}302 303static int st_lsm6dsx_reset_hw_ts(struct st_lsm6dsx_hw *hw)304{305 struct st_lsm6dsx_sensor *sensor;306 int i, err;307 308 /* reset hw ts counter */309 err = st_lsm6dsx_write_locked(hw, ST_LSM6DSX_REG_TS_RESET_ADDR,310 ST_LSM6DSX_TS_RESET_VAL);311 if (err < 0)312 return err;313 314 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {315 if (!hw->iio_devs[i])316 continue;317 318 sensor = iio_priv(hw->iio_devs[i]);319 /*320 * store enable buffer timestamp as reference for321 * hw timestamp322 */323 sensor->ts_ref = iio_get_time_ns(hw->iio_devs[i]);324 }325 return 0;326}327 328int st_lsm6dsx_resume_fifo(struct st_lsm6dsx_hw *hw)329{330 int err;331 332 /* reset hw ts counter */333 err = st_lsm6dsx_reset_hw_ts(hw);334 if (err < 0)335 return err;336 337 return st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_CONT);338}339 340/*341 * Set max bulk read to ST_LSM6DSX_MAX_WORD_LEN/ST_LSM6DSX_MAX_TAGGED_WORD_LEN342 * in order to avoid a kmalloc for each bus access343 */344static inline int st_lsm6dsx_read_block(struct st_lsm6dsx_hw *hw, u8 addr,345 u8 *data, unsigned int data_len,346 unsigned int max_word_len)347{348 unsigned int word_len, read_len = 0;349 int err;350 351 while (read_len < data_len) {352 word_len = min_t(unsigned int, data_len - read_len,353 max_word_len);354 err = st_lsm6dsx_read_locked(hw, addr, data + read_len,355 word_len);356 if (err < 0)357 return err;358 read_len += word_len;359 }360 return 0;361}362 363#define ST_LSM6DSX_IIO_BUFF_SIZE (ALIGN(ST_LSM6DSX_SAMPLE_SIZE, \364 sizeof(s64)) + sizeof(s64))365/**366 * st_lsm6dsx_read_fifo() - hw FIFO read routine367 * @hw: Pointer to instance of struct st_lsm6dsx_hw.368 *369 * Read samples from the hw FIFO and push them to IIO buffers.370 *371 * Return: Number of bytes read from the FIFO372 */373int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)374{375 struct st_lsm6dsx_sensor *acc_sensor, *gyro_sensor, *ext_sensor = NULL;376 int err, sip, acc_sip, gyro_sip, ts_sip, ext_sip, read_len, offset;377 u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE;378 u16 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask;379 bool reset_ts = false;380 __le16 fifo_status;381 s64 ts = 0;382 383 err = st_lsm6dsx_read_locked(hw,384 hw->settings->fifo_ops.fifo_diff.addr,385 &fifo_status, sizeof(fifo_status));386 if (err < 0) {387 dev_err(hw->dev, "failed to read fifo status (err=%d)\n",388 err);389 return err;390 }391 392 if (fifo_status & cpu_to_le16(ST_LSM6DSX_FIFO_EMPTY_MASK))393 return 0;394 395 fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) *396 ST_LSM6DSX_CHAN_SIZE;397 fifo_len = (fifo_len / pattern_len) * pattern_len;398 399 acc_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]);400 gyro_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_GYRO]);401 if (hw->iio_devs[ST_LSM6DSX_ID_EXT0])402 ext_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_EXT0]);403 404 for (read_len = 0; read_len < fifo_len; read_len += pattern_len) {405 err = st_lsm6dsx_read_block(hw, ST_LSM6DSX_REG_FIFO_OUTL_ADDR,406 hw->buff, pattern_len,407 ST_LSM6DSX_MAX_WORD_LEN);408 if (err < 0) {409 dev_err(hw->dev,410 "failed to read pattern from fifo (err=%d)\n",411 err);412 return err;413 }414 415 /*416 * Data are written to the FIFO with a specific pattern417 * depending on the configured ODRs. The first sequence of data418 * stored in FIFO contains the data of all enabled sensors419 * (e.g. Gx, Gy, Gz, Ax, Ay, Az, Ts), then data are repeated420 * depending on the value of the decimation factor set for each421 * sensor.422 *423 * Supposing the FIFO is storing data from gyroscope and424 * accelerometer at different ODRs:425 * - gyroscope ODR = 208Hz, accelerometer ODR = 104Hz426 * Since the gyroscope ODR is twice the accelerometer one, the427 * following pattern is repeated every 9 samples:428 * - Gx, Gy, Gz, Ax, Ay, Az, Ts, Gx, Gy, Gz, Ts, Gx, ..429 */430 ext_sip = ext_sensor ? ext_sensor->sip : 0;431 gyro_sip = gyro_sensor->sip;432 acc_sip = acc_sensor->sip;433 ts_sip = hw->ts_sip;434 offset = 0;435 sip = 0;436 437 while (acc_sip > 0 || gyro_sip > 0 || ext_sip > 0) {438 if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) {439 memcpy(hw->scan[ST_LSM6DSX_ID_GYRO].channels,440 &hw->buff[offset],441 sizeof(hw->scan[ST_LSM6DSX_ID_GYRO].channels));442 offset += sizeof(hw->scan[ST_LSM6DSX_ID_GYRO].channels);443 }444 if (acc_sip > 0 && !(sip % acc_sensor->decimator)) {445 memcpy(hw->scan[ST_LSM6DSX_ID_ACC].channels,446 &hw->buff[offset],447 sizeof(hw->scan[ST_LSM6DSX_ID_ACC].channels));448 offset += sizeof(hw->scan[ST_LSM6DSX_ID_ACC].channels);449 }450 if (ext_sip > 0 && !(sip % ext_sensor->decimator)) {451 memcpy(hw->scan[ST_LSM6DSX_ID_EXT0].channels,452 &hw->buff[offset],453 sizeof(hw->scan[ST_LSM6DSX_ID_EXT0].channels));454 offset += sizeof(hw->scan[ST_LSM6DSX_ID_EXT0].channels);455 }456 457 if (ts_sip-- > 0) {458 u8 data[ST_LSM6DSX_SAMPLE_SIZE];459 460 memcpy(data, &hw->buff[offset], sizeof(data));461 /*462 * hw timestamp is 3B long and it is stored463 * in FIFO using 6B as 4th FIFO data set464 * according to this schema:465 * B0 = ts[15:8], B1 = ts[23:16], B3 = ts[7:0]466 */467 ts = data[1] << 16 | data[0] << 8 | data[3];468 /*469 * check if hw timestamp engine is going to470 * reset (the sensor generates an interrupt471 * to signal the hw timestamp will reset in472 * 1.638s)473 */474 if (!reset_ts && ts >= 0xff0000)475 reset_ts = true;476 ts *= hw->ts_gain;477 478 offset += ST_LSM6DSX_SAMPLE_SIZE;479 }480 481 if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) {482 /*483 * We need to discards gyro samples during484 * filters settling time485 */486 if (gyro_sensor->samples_to_discard > 0)487 gyro_sensor->samples_to_discard--;488 else489 iio_push_to_buffers_with_timestamp(490 hw->iio_devs[ST_LSM6DSX_ID_GYRO],491 &hw->scan[ST_LSM6DSX_ID_GYRO],492 gyro_sensor->ts_ref + ts);493 gyro_sip--;494 }495 if (acc_sip > 0 && !(sip % acc_sensor->decimator)) {496 /*497 * We need to discards accel samples during498 * filters settling time499 */500 if (acc_sensor->samples_to_discard > 0)501 acc_sensor->samples_to_discard--;502 else503 iio_push_to_buffers_with_timestamp(504 hw->iio_devs[ST_LSM6DSX_ID_ACC],505 &hw->scan[ST_LSM6DSX_ID_ACC],506 acc_sensor->ts_ref + ts);507 acc_sip--;508 }509 if (ext_sip > 0 && !(sip % ext_sensor->decimator)) {510 iio_push_to_buffers_with_timestamp(511 hw->iio_devs[ST_LSM6DSX_ID_EXT0],512 &hw->scan[ST_LSM6DSX_ID_EXT0],513 ext_sensor->ts_ref + ts);514 ext_sip--;515 }516 sip++;517 }518 }519 520 if (unlikely(reset_ts)) {521 err = st_lsm6dsx_reset_hw_ts(hw);522 if (err < 0) {523 dev_err(hw->dev, "failed to reset hw ts (err=%d)\n",524 err);525 return err;526 }527 }528 return read_len;529}530 531#define ST_LSM6DSX_INVALID_SAMPLE 0x7ffd532static int533st_lsm6dsx_push_tagged_data(struct st_lsm6dsx_hw *hw, u8 tag,534 u8 *data, s64 ts)535{536 s16 val = le16_to_cpu(*(__le16 *)data);537 struct st_lsm6dsx_sensor *sensor;538 struct iio_dev *iio_dev;539 540 /* invalid sample during bootstrap phase */541 if (val >= ST_LSM6DSX_INVALID_SAMPLE)542 return -EINVAL;543 544 /*545 * EXT_TAG are managed in FIFO fashion so ST_LSM6DSX_EXT0_TAG546 * corresponds to the first enabled channel, ST_LSM6DSX_EXT1_TAG547 * to the second one and ST_LSM6DSX_EXT2_TAG to the last enabled548 * channel549 */550 switch (tag) {551 case ST_LSM6DSX_GYRO_TAG:552 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_GYRO];553 break;554 case ST_LSM6DSX_ACC_TAG:555 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_ACC];556 break;557 case ST_LSM6DSX_EXT0_TAG:558 if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0))559 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT0];560 else if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1))561 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1];562 else563 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2];564 break;565 case ST_LSM6DSX_EXT1_TAG:566 if ((hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0)) &&567 (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1)))568 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1];569 else570 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2];571 break;572 case ST_LSM6DSX_EXT2_TAG:573 iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2];574 break;575 default:576 return -EINVAL;577 }578 579 sensor = iio_priv(iio_dev);580 iio_push_to_buffers_with_timestamp(iio_dev, data,581 ts + sensor->ts_ref);582 583 return 0;584}585 586/**587 * st_lsm6dsx_read_tagged_fifo() - tagged hw FIFO read routine588 * @hw: Pointer to instance of struct st_lsm6dsx_hw.589 *590 * Read samples from the hw FIFO and push them to IIO buffers.591 *592 * Return: Number of bytes read from the FIFO593 */594int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw)595{596 u16 pattern_len = hw->sip * ST_LSM6DSX_TAGGED_SAMPLE_SIZE;597 u16 fifo_len, fifo_diff_mask;598 /*599 * Alignment needed as this can ultimately be passed to a600 * call to iio_push_to_buffers_with_timestamp() which601 * must be passed a buffer that is aligned to 8 bytes so602 * as to allow insertion of a naturally aligned timestamp.603 */604 u8 iio_buff[ST_LSM6DSX_IIO_BUFF_SIZE] __aligned(8);605 u8 tag;606 bool reset_ts = false;607 int i, err, read_len;608 __le16 fifo_status;609 s64 ts = 0;610 611 err = st_lsm6dsx_read_locked(hw,612 hw->settings->fifo_ops.fifo_diff.addr,613 &fifo_status, sizeof(fifo_status));614 if (err < 0) {615 dev_err(hw->dev, "failed to read fifo status (err=%d)\n",616 err);617 return err;618 }619 620 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask;621 fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) *622 ST_LSM6DSX_TAGGED_SAMPLE_SIZE;623 if (!fifo_len)624 return 0;625 626 for (read_len = 0; read_len < fifo_len; read_len += pattern_len) {627 err = st_lsm6dsx_read_block(hw,628 ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR,629 hw->buff, pattern_len,630 ST_LSM6DSX_MAX_TAGGED_WORD_LEN);631 if (err < 0) {632 dev_err(hw->dev,633 "failed to read pattern from fifo (err=%d)\n",634 err);635 return err;636 }637 638 for (i = 0; i < pattern_len;639 i += ST_LSM6DSX_TAGGED_SAMPLE_SIZE) {640 memcpy(iio_buff, &hw->buff[i + ST_LSM6DSX_TAG_SIZE],641 ST_LSM6DSX_SAMPLE_SIZE);642 643 tag = hw->buff[i] >> 3;644 if (tag == ST_LSM6DSX_TS_TAG) {645 /*646 * hw timestamp is 4B long and it is stored647 * in FIFO according to this schema:648 * B0 = ts[7:0], B1 = ts[15:8], B2 = ts[23:16],649 * B3 = ts[31:24]650 */651 ts = le32_to_cpu(*((__le32 *)iio_buff));652 /*653 * check if hw timestamp engine is going to654 * reset (the sensor generates an interrupt655 * to signal the hw timestamp will reset in656 * 1.638s)657 */658 if (!reset_ts && ts >= 0xffff0000)659 reset_ts = true;660 ts *= hw->ts_gain;661 } else {662 st_lsm6dsx_push_tagged_data(hw, tag, iio_buff,663 ts);664 }665 }666 }667 668 if (unlikely(reset_ts)) {669 err = st_lsm6dsx_reset_hw_ts(hw);670 if (err < 0)671 return err;672 }673 return read_len;674}675 676int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw)677{678 int err;679 680 if (!hw->settings->fifo_ops.read_fifo)681 return -ENOTSUPP;682 683 mutex_lock(&hw->fifo_lock);684 685 hw->settings->fifo_ops.read_fifo(hw);686 err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS);687 688 mutex_unlock(&hw->fifo_lock);689 690 return err;691}692 693static void694st_lsm6dsx_update_samples_to_discard(struct st_lsm6dsx_sensor *sensor)695{696 const struct st_lsm6dsx_samples_to_discard *data;697 struct st_lsm6dsx_hw *hw = sensor->hw;698 int i;699 700 if (sensor->id != ST_LSM6DSX_ID_GYRO &&701 sensor->id != ST_LSM6DSX_ID_ACC)702 return;703 704 /* check if drdy mask is supported in hw */705 if (hw->settings->drdy_mask.addr)706 return;707 708 data = &hw->settings->samples_to_discard[sensor->id];709 for (i = 0; i < ST_LSM6DSX_ODR_LIST_SIZE; i++) {710 if (data->val[i].milli_hz == sensor->odr) {711 sensor->samples_to_discard = data->val[i].samples;712 return;713 }714 }715}716 717int st_lsm6dsx_update_fifo(struct st_lsm6dsx_sensor *sensor, bool enable)718{719 struct st_lsm6dsx_hw *hw = sensor->hw;720 u8 fifo_mask;721 int err;722 723 mutex_lock(&hw->conf_lock);724 725 if (enable)726 fifo_mask = hw->fifo_mask | BIT(sensor->id);727 else728 fifo_mask = hw->fifo_mask & ~BIT(sensor->id);729 730 if (hw->fifo_mask) {731 err = st_lsm6dsx_flush_fifo(hw);732 if (err < 0)733 goto out;734 }735 736 if (enable)737 st_lsm6dsx_update_samples_to_discard(sensor);738 739 err = st_lsm6dsx_device_set_enable(sensor, enable);740 if (err < 0)741 goto out;742 743 err = st_lsm6dsx_set_fifo_odr(sensor, enable);744 if (err < 0)745 goto out;746 747 err = st_lsm6dsx_update_decimators(hw);748 if (err < 0)749 goto out;750 751 err = st_lsm6dsx_update_watermark(sensor, sensor->watermark);752 if (err < 0)753 goto out;754 755 if (fifo_mask) {756 err = st_lsm6dsx_resume_fifo(hw);757 if (err < 0)758 goto out;759 }760 761 hw->fifo_mask = fifo_mask;762 763out:764 mutex_unlock(&hw->conf_lock);765 766 return err;767}768 769static int st_lsm6dsx_buffer_preenable(struct iio_dev *iio_dev)770{771 struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);772 struct st_lsm6dsx_hw *hw = sensor->hw;773 774 if (!hw->settings->fifo_ops.update_fifo)775 return -ENOTSUPP;776 777 return hw->settings->fifo_ops.update_fifo(sensor, true);778}779 780static int st_lsm6dsx_buffer_postdisable(struct iio_dev *iio_dev)781{782 struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);783 struct st_lsm6dsx_hw *hw = sensor->hw;784 785 if (!hw->settings->fifo_ops.update_fifo)786 return -ENOTSUPP;787 788 return hw->settings->fifo_ops.update_fifo(sensor, false);789}790 791static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = {792 .preenable = st_lsm6dsx_buffer_preenable,793 .postdisable = st_lsm6dsx_buffer_postdisable,794};795 796int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw)797{798 int i, ret;799 800 for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {801 if (!hw->iio_devs[i])802 continue;803 804 ret = devm_iio_kfifo_buffer_setup(hw->dev, hw->iio_devs[i],805 &st_lsm6dsx_buffer_ops);806 if (ret)807 return ret;808 }809 810 return 0;811}812