diff options
Diffstat (limited to 'drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c')
-rw-r--r-- | drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c | 789 |
1 files changed, 789 insertions, 0 deletions
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c new file mode 100644 index 0000000000..066fe561c5 --- /dev/null +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c @@ -0,0 +1,789 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * STMicroelectronics st_lsm6dsx FIFO buffer library driver + * + * LSM6DS3/LSM6DS3H/LSM6DSL/LSM6DSM/ISM330DLC/LSM6DS3TR-C: + * The FIFO buffer can be configured to store data from gyroscope and + * accelerometer. Samples are queued without any tag according to a + * specific pattern based on 'FIFO data sets' (6 bytes each): + * - 1st data set is reserved for gyroscope data + * - 2nd data set is reserved for accelerometer data + * The FIFO pattern changes depending on the ODRs and decimation factors + * assigned to the FIFO data sets. The first sequence of data stored in FIFO + * buffer contains the data of all the enabled FIFO data sets + * (e.g. Gx, Gy, Gz, Ax, Ay, Az), then data are repeated depending on the + * value of the decimation factor and ODR set for each FIFO data set. + * + * LSM6DSO/LSM6DSOX/ASM330LHH/ASM330LHHX/LSM6DSR/LSM6DSRX/ISM330DHCX/ + * LSM6DST/LSM6DSOP/LSM6DSTX/LSM6DSV/ASM330LHB: + * The FIFO buffer can be configured to store data from gyroscope and + * accelerometer. Each sample is queued with a tag (1B) indicating data + * source (gyroscope, accelerometer, hw timer). + * + * FIFO supported modes: + * - BYPASS: FIFO disabled + * - CONTINUOUS: FIFO enabled. When the buffer is full, the FIFO index + * restarts from the beginning and the oldest sample is overwritten + * + * Copyright 2016 STMicroelectronics Inc. + * + * Lorenzo Bianconi <lorenzo.bianconi@st.com> + * Denis Ciocca <denis.ciocca@st.com> + */ +#include <linux/module.h> +#include <linux/iio/kfifo_buf.h> +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/regmap.h> +#include <linux/bitfield.h> + +#include <linux/platform_data/st_sensors_pdata.h> + +#include "st_lsm6dsx.h" + +#define ST_LSM6DSX_REG_FIFO_MODE_ADDR 0x0a +#define ST_LSM6DSX_FIFO_MODE_MASK GENMASK(2, 0) +#define ST_LSM6DSX_FIFO_ODR_MASK GENMASK(6, 3) +#define ST_LSM6DSX_FIFO_EMPTY_MASK BIT(12) +#define ST_LSM6DSX_REG_FIFO_OUTL_ADDR 0x3e +#define ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR 0x78 +#define ST_LSM6DSX_REG_TS_RESET_ADDR 0x42 + +#define ST_LSM6DSX_MAX_FIFO_ODR_VAL 0x08 + +#define ST_LSM6DSX_TS_RESET_VAL 0xaa + +struct st_lsm6dsx_decimator_entry { + u8 decimator; + u8 val; +}; + +enum st_lsm6dsx_fifo_tag { + ST_LSM6DSX_GYRO_TAG = 0x01, + ST_LSM6DSX_ACC_TAG = 0x02, + ST_LSM6DSX_TS_TAG = 0x04, + ST_LSM6DSX_EXT0_TAG = 0x0f, + ST_LSM6DSX_EXT1_TAG = 0x10, + ST_LSM6DSX_EXT2_TAG = 0x11, +}; + +static const +struct st_lsm6dsx_decimator_entry st_lsm6dsx_decimator_table[] = { + { 0, 0x0 }, + { 1, 0x1 }, + { 2, 0x2 }, + { 3, 0x3 }, + { 4, 0x4 }, + { 8, 0x5 }, + { 16, 0x6 }, + { 32, 0x7 }, +}; + +static int +st_lsm6dsx_get_decimator_val(struct st_lsm6dsx_sensor *sensor, u32 max_odr) +{ + const int max_size = ARRAY_SIZE(st_lsm6dsx_decimator_table); + u32 decimator = max_odr / sensor->odr; + int i; + + if (decimator > 1) + decimator = round_down(decimator, 2); + + for (i = 0; i < max_size; i++) { + if (st_lsm6dsx_decimator_table[i].decimator == decimator) + break; + } + + sensor->decimator = decimator; + return i == max_size ? 0 : st_lsm6dsx_decimator_table[i].val; +} + +static void st_lsm6dsx_get_max_min_odr(struct st_lsm6dsx_hw *hw, + u32 *max_odr, u32 *min_odr) +{ + struct st_lsm6dsx_sensor *sensor; + int i; + + *max_odr = 0, *min_odr = ~0; + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { + if (!hw->iio_devs[i]) + continue; + + sensor = iio_priv(hw->iio_devs[i]); + + if (!(hw->enable_mask & BIT(sensor->id))) + continue; + + *max_odr = max_t(u32, *max_odr, sensor->odr); + *min_odr = min_t(u32, *min_odr, sensor->odr); + } +} + +static u8 st_lsm6dsx_get_sip(struct st_lsm6dsx_sensor *sensor, u32 min_odr) +{ + u8 sip = sensor->odr / min_odr; + + return sip > 1 ? round_down(sip, 2) : sip; +} + +static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw) +{ + const struct st_lsm6dsx_reg *ts_dec_reg; + struct st_lsm6dsx_sensor *sensor; + u16 sip = 0, ts_sip = 0; + u32 max_odr, min_odr; + int err = 0, i; + u8 data; + + st_lsm6dsx_get_max_min_odr(hw, &max_odr, &min_odr); + + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { + const struct st_lsm6dsx_reg *dec_reg; + + if (!hw->iio_devs[i]) + continue; + + sensor = iio_priv(hw->iio_devs[i]); + /* update fifo decimators and sample in pattern */ + if (hw->enable_mask & BIT(sensor->id)) { + sensor->sip = st_lsm6dsx_get_sip(sensor, min_odr); + data = st_lsm6dsx_get_decimator_val(sensor, max_odr); + } else { + sensor->sip = 0; + data = 0; + } + ts_sip = max_t(u16, ts_sip, sensor->sip); + + dec_reg = &hw->settings->decimator[sensor->id]; + if (dec_reg->addr) { + int val = ST_LSM6DSX_SHIFT_VAL(data, dec_reg->mask); + + err = st_lsm6dsx_update_bits_locked(hw, dec_reg->addr, + dec_reg->mask, + val); + if (err < 0) + return err; + } + sip += sensor->sip; + } + hw->sip = sip + ts_sip; + hw->ts_sip = ts_sip; + + /* + * update hw ts decimator if necessary. Decimator for hw timestamp + * is always 1 or 0 in order to have a ts sample for each data + * sample in FIFO + */ + ts_dec_reg = &hw->settings->ts_settings.decimator; + if (ts_dec_reg->addr) { + int val, ts_dec = !!hw->ts_sip; + + val = ST_LSM6DSX_SHIFT_VAL(ts_dec, ts_dec_reg->mask); + err = st_lsm6dsx_update_bits_locked(hw, ts_dec_reg->addr, + ts_dec_reg->mask, val); + } + return err; +} + +static int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw, + enum st_lsm6dsx_fifo_mode fifo_mode) +{ + unsigned int data; + + data = FIELD_PREP(ST_LSM6DSX_FIFO_MODE_MASK, fifo_mode); + return st_lsm6dsx_update_bits_locked(hw, ST_LSM6DSX_REG_FIFO_MODE_ADDR, + ST_LSM6DSX_FIFO_MODE_MASK, data); +} + +static int st_lsm6dsx_set_fifo_odr(struct st_lsm6dsx_sensor *sensor, + bool enable) +{ + struct st_lsm6dsx_hw *hw = sensor->hw; + const struct st_lsm6dsx_reg *batch_reg; + u8 data; + + batch_reg = &hw->settings->batch[sensor->id]; + if (batch_reg->addr) { + int val; + + if (enable) { + int err; + + err = st_lsm6dsx_check_odr(sensor, sensor->odr, + &data); + if (err < 0) + return err; + } else { + data = 0; + } + val = ST_LSM6DSX_SHIFT_VAL(data, batch_reg->mask); + return st_lsm6dsx_update_bits_locked(hw, batch_reg->addr, + batch_reg->mask, val); + } else { + data = hw->enable_mask ? ST_LSM6DSX_MAX_FIFO_ODR_VAL : 0; + return st_lsm6dsx_update_bits_locked(hw, + ST_LSM6DSX_REG_FIFO_MODE_ADDR, + ST_LSM6DSX_FIFO_ODR_MASK, + FIELD_PREP(ST_LSM6DSX_FIFO_ODR_MASK, + data)); + } +} + +int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor, u16 watermark) +{ + u16 fifo_watermark = ~0, cur_watermark, fifo_th_mask; + struct st_lsm6dsx_hw *hw = sensor->hw; + struct st_lsm6dsx_sensor *cur_sensor; + int i, err, data; + __le16 wdata; + + if (!hw->sip) + return 0; + + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { + if (!hw->iio_devs[i]) + continue; + + cur_sensor = iio_priv(hw->iio_devs[i]); + + if (!(hw->enable_mask & BIT(cur_sensor->id))) + continue; + + cur_watermark = (cur_sensor == sensor) ? watermark + : cur_sensor->watermark; + + fifo_watermark = min_t(u16, fifo_watermark, cur_watermark); + } + + fifo_watermark = max_t(u16, fifo_watermark, hw->sip); + fifo_watermark = (fifo_watermark / hw->sip) * hw->sip; + fifo_watermark = fifo_watermark * hw->settings->fifo_ops.th_wl; + + mutex_lock(&hw->page_lock); + err = regmap_read(hw->regmap, hw->settings->fifo_ops.fifo_th.addr + 1, + &data); + if (err < 0) + goto out; + + fifo_th_mask = hw->settings->fifo_ops.fifo_th.mask; + fifo_watermark = ((data << 8) & ~fifo_th_mask) | + (fifo_watermark & fifo_th_mask); + + wdata = cpu_to_le16(fifo_watermark); + err = regmap_bulk_write(hw->regmap, + hw->settings->fifo_ops.fifo_th.addr, + &wdata, sizeof(wdata)); +out: + mutex_unlock(&hw->page_lock); + return err; +} + +static int st_lsm6dsx_reset_hw_ts(struct st_lsm6dsx_hw *hw) +{ + struct st_lsm6dsx_sensor *sensor; + int i, err; + + /* reset hw ts counter */ + err = st_lsm6dsx_write_locked(hw, ST_LSM6DSX_REG_TS_RESET_ADDR, + ST_LSM6DSX_TS_RESET_VAL); + if (err < 0) + return err; + + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { + if (!hw->iio_devs[i]) + continue; + + sensor = iio_priv(hw->iio_devs[i]); + /* + * store enable buffer timestamp as reference for + * hw timestamp + */ + sensor->ts_ref = iio_get_time_ns(hw->iio_devs[i]); + } + return 0; +} + +int st_lsm6dsx_resume_fifo(struct st_lsm6dsx_hw *hw) +{ + int err; + + /* reset hw ts counter */ + err = st_lsm6dsx_reset_hw_ts(hw); + if (err < 0) + return err; + + return st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_CONT); +} + +/* + * Set max bulk read to ST_LSM6DSX_MAX_WORD_LEN/ST_LSM6DSX_MAX_TAGGED_WORD_LEN + * in order to avoid a kmalloc for each bus access + */ +static inline int st_lsm6dsx_read_block(struct st_lsm6dsx_hw *hw, u8 addr, + u8 *data, unsigned int data_len, + unsigned int max_word_len) +{ + unsigned int word_len, read_len = 0; + int err; + + while (read_len < data_len) { + word_len = min_t(unsigned int, data_len - read_len, + max_word_len); + err = st_lsm6dsx_read_locked(hw, addr, data + read_len, + word_len); + if (err < 0) + return err; + read_len += word_len; + } + return 0; +} + +#define ST_LSM6DSX_IIO_BUFF_SIZE (ALIGN(ST_LSM6DSX_SAMPLE_SIZE, \ + sizeof(s64)) + sizeof(s64)) +/** + * st_lsm6dsx_read_fifo() - hw FIFO read routine + * @hw: Pointer to instance of struct st_lsm6dsx_hw. + * + * Read samples from the hw FIFO and push them to IIO buffers. + * + * Return: Number of bytes read from the FIFO + */ +int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw) +{ + struct st_lsm6dsx_sensor *acc_sensor, *gyro_sensor, *ext_sensor = NULL; + int err, sip, acc_sip, gyro_sip, ts_sip, ext_sip, read_len, offset; + u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE; + u16 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask; + bool reset_ts = false; + __le16 fifo_status; + s64 ts = 0; + + err = st_lsm6dsx_read_locked(hw, + hw->settings->fifo_ops.fifo_diff.addr, + &fifo_status, sizeof(fifo_status)); + if (err < 0) { + dev_err(hw->dev, "failed to read fifo status (err=%d)\n", + err); + return err; + } + + if (fifo_status & cpu_to_le16(ST_LSM6DSX_FIFO_EMPTY_MASK)) + return 0; + + fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) * + ST_LSM6DSX_CHAN_SIZE; + fifo_len = (fifo_len / pattern_len) * pattern_len; + + acc_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]); + gyro_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_GYRO]); + if (hw->iio_devs[ST_LSM6DSX_ID_EXT0]) + ext_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_EXT0]); + + for (read_len = 0; read_len < fifo_len; read_len += pattern_len) { + err = st_lsm6dsx_read_block(hw, ST_LSM6DSX_REG_FIFO_OUTL_ADDR, + hw->buff, pattern_len, + ST_LSM6DSX_MAX_WORD_LEN); + if (err < 0) { + dev_err(hw->dev, + "failed to read pattern from fifo (err=%d)\n", + err); + return err; + } + + /* + * Data are written to the FIFO with a specific pattern + * depending on the configured ODRs. The first sequence of data + * stored in FIFO contains the data of all enabled sensors + * (e.g. Gx, Gy, Gz, Ax, Ay, Az, Ts), then data are repeated + * depending on the value of the decimation factor set for each + * sensor. + * + * Supposing the FIFO is storing data from gyroscope and + * accelerometer at different ODRs: + * - gyroscope ODR = 208Hz, accelerometer ODR = 104Hz + * Since the gyroscope ODR is twice the accelerometer one, the + * following pattern is repeated every 9 samples: + * - Gx, Gy, Gz, Ax, Ay, Az, Ts, Gx, Gy, Gz, Ts, Gx, .. + */ + ext_sip = ext_sensor ? ext_sensor->sip : 0; + gyro_sip = gyro_sensor->sip; + acc_sip = acc_sensor->sip; + ts_sip = hw->ts_sip; + offset = 0; + sip = 0; + + while (acc_sip > 0 || gyro_sip > 0 || ext_sip > 0) { + if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) { + memcpy(hw->scan[ST_LSM6DSX_ID_GYRO].channels, + &hw->buff[offset], + sizeof(hw->scan[ST_LSM6DSX_ID_GYRO].channels)); + offset += sizeof(hw->scan[ST_LSM6DSX_ID_GYRO].channels); + } + if (acc_sip > 0 && !(sip % acc_sensor->decimator)) { + memcpy(hw->scan[ST_LSM6DSX_ID_ACC].channels, + &hw->buff[offset], + sizeof(hw->scan[ST_LSM6DSX_ID_ACC].channels)); + offset += sizeof(hw->scan[ST_LSM6DSX_ID_ACC].channels); + } + if (ext_sip > 0 && !(sip % ext_sensor->decimator)) { + memcpy(hw->scan[ST_LSM6DSX_ID_EXT0].channels, + &hw->buff[offset], + sizeof(hw->scan[ST_LSM6DSX_ID_EXT0].channels)); + offset += sizeof(hw->scan[ST_LSM6DSX_ID_EXT0].channels); + } + + if (ts_sip-- > 0) { + u8 data[ST_LSM6DSX_SAMPLE_SIZE]; + + memcpy(data, &hw->buff[offset], sizeof(data)); + /* + * hw timestamp is 3B long and it is stored + * in FIFO using 6B as 4th FIFO data set + * according to this schema: + * B0 = ts[15:8], B1 = ts[23:16], B3 = ts[7:0] + */ + ts = data[1] << 16 | data[0] << 8 | data[3]; + /* + * check if hw timestamp engine is going to + * reset (the sensor generates an interrupt + * to signal the hw timestamp will reset in + * 1.638s) + */ + if (!reset_ts && ts >= 0xff0000) + reset_ts = true; + ts *= hw->ts_gain; + + offset += ST_LSM6DSX_SAMPLE_SIZE; + } + + if (gyro_sip > 0 && !(sip % gyro_sensor->decimator)) { + /* + * We need to discards gyro samples during + * filters settling time + */ + if (gyro_sensor->samples_to_discard > 0) + gyro_sensor->samples_to_discard--; + else + iio_push_to_buffers_with_timestamp( + hw->iio_devs[ST_LSM6DSX_ID_GYRO], + &hw->scan[ST_LSM6DSX_ID_GYRO], + gyro_sensor->ts_ref + ts); + gyro_sip--; + } + if (acc_sip > 0 && !(sip % acc_sensor->decimator)) { + /* + * We need to discards accel samples during + * filters settling time + */ + if (acc_sensor->samples_to_discard > 0) + acc_sensor->samples_to_discard--; + else + iio_push_to_buffers_with_timestamp( + hw->iio_devs[ST_LSM6DSX_ID_ACC], + &hw->scan[ST_LSM6DSX_ID_ACC], + acc_sensor->ts_ref + ts); + acc_sip--; + } + if (ext_sip > 0 && !(sip % ext_sensor->decimator)) { + iio_push_to_buffers_with_timestamp( + hw->iio_devs[ST_LSM6DSX_ID_EXT0], + &hw->scan[ST_LSM6DSX_ID_EXT0], + ext_sensor->ts_ref + ts); + ext_sip--; + } + sip++; + } + } + + if (unlikely(reset_ts)) { + err = st_lsm6dsx_reset_hw_ts(hw); + if (err < 0) { + dev_err(hw->dev, "failed to reset hw ts (err=%d)\n", + err); + return err; + } + } + return read_len; +} + +#define ST_LSM6DSX_INVALID_SAMPLE 0x7ffd +static int +st_lsm6dsx_push_tagged_data(struct st_lsm6dsx_hw *hw, u8 tag, + u8 *data, s64 ts) +{ + s16 val = le16_to_cpu(*(__le16 *)data); + struct st_lsm6dsx_sensor *sensor; + struct iio_dev *iio_dev; + + /* invalid sample during bootstrap phase */ + if (val >= ST_LSM6DSX_INVALID_SAMPLE) + return -EINVAL; + + /* + * EXT_TAG are managed in FIFO fashion so ST_LSM6DSX_EXT0_TAG + * corresponds to the first enabled channel, ST_LSM6DSX_EXT1_TAG + * to the second one and ST_LSM6DSX_EXT2_TAG to the last enabled + * channel + */ + switch (tag) { + case ST_LSM6DSX_GYRO_TAG: + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_GYRO]; + break; + case ST_LSM6DSX_ACC_TAG: + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_ACC]; + break; + case ST_LSM6DSX_EXT0_TAG: + if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0)) + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT0]; + else if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1)) + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1]; + else + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; + break; + case ST_LSM6DSX_EXT1_TAG: + if ((hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0)) && + (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1))) + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1]; + else + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; + break; + case ST_LSM6DSX_EXT2_TAG: + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2]; + break; + default: + return -EINVAL; + } + + sensor = iio_priv(iio_dev); + iio_push_to_buffers_with_timestamp(iio_dev, data, + ts + sensor->ts_ref); + + return 0; +} + +/** + * st_lsm6dsx_read_tagged_fifo() - tagged hw FIFO read routine + * @hw: Pointer to instance of struct st_lsm6dsx_hw. + * + * Read samples from the hw FIFO and push them to IIO buffers. + * + * Return: Number of bytes read from the FIFO + */ +int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw) +{ + u16 pattern_len = hw->sip * ST_LSM6DSX_TAGGED_SAMPLE_SIZE; + u16 fifo_len, fifo_diff_mask; + /* + * Alignment needed as this can ultimately be passed to a + * call to iio_push_to_buffers_with_timestamp() which + * must be passed a buffer that is aligned to 8 bytes so + * as to allow insertion of a naturally aligned timestamp. + */ + u8 iio_buff[ST_LSM6DSX_IIO_BUFF_SIZE] __aligned(8); + u8 tag; + bool reset_ts = false; + int i, err, read_len; + __le16 fifo_status; + s64 ts = 0; + + err = st_lsm6dsx_read_locked(hw, + hw->settings->fifo_ops.fifo_diff.addr, + &fifo_status, sizeof(fifo_status)); + if (err < 0) { + dev_err(hw->dev, "failed to read fifo status (err=%d)\n", + err); + return err; + } + + fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask; + fifo_len = (le16_to_cpu(fifo_status) & fifo_diff_mask) * + ST_LSM6DSX_TAGGED_SAMPLE_SIZE; + if (!fifo_len) + return 0; + + for (read_len = 0; read_len < fifo_len; read_len += pattern_len) { + err = st_lsm6dsx_read_block(hw, + ST_LSM6DSX_REG_FIFO_OUT_TAG_ADDR, + hw->buff, pattern_len, + ST_LSM6DSX_MAX_TAGGED_WORD_LEN); + if (err < 0) { + dev_err(hw->dev, + "failed to read pattern from fifo (err=%d)\n", + err); + return err; + } + + for (i = 0; i < pattern_len; + i += ST_LSM6DSX_TAGGED_SAMPLE_SIZE) { + memcpy(iio_buff, &hw->buff[i + ST_LSM6DSX_TAG_SIZE], + ST_LSM6DSX_SAMPLE_SIZE); + + tag = hw->buff[i] >> 3; + if (tag == ST_LSM6DSX_TS_TAG) { + /* + * hw timestamp is 4B long and it is stored + * in FIFO according to this schema: + * B0 = ts[7:0], B1 = ts[15:8], B2 = ts[23:16], + * B3 = ts[31:24] + */ + ts = le32_to_cpu(*((__le32 *)iio_buff)); + /* + * check if hw timestamp engine is going to + * reset (the sensor generates an interrupt + * to signal the hw timestamp will reset in + * 1.638s) + */ + if (!reset_ts && ts >= 0xffff0000) + reset_ts = true; + ts *= hw->ts_gain; + } else { + st_lsm6dsx_push_tagged_data(hw, tag, iio_buff, + ts); + } + } + } + + if (unlikely(reset_ts)) { + err = st_lsm6dsx_reset_hw_ts(hw); + if (err < 0) + return err; + } + return read_len; +} + +int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw) +{ + int err; + + if (!hw->settings->fifo_ops.read_fifo) + return -ENOTSUPP; + + mutex_lock(&hw->fifo_lock); + + hw->settings->fifo_ops.read_fifo(hw); + err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS); + + mutex_unlock(&hw->fifo_lock); + + return err; +} + +static void +st_lsm6dsx_update_samples_to_discard(struct st_lsm6dsx_sensor *sensor) +{ + const struct st_lsm6dsx_samples_to_discard *data; + struct st_lsm6dsx_hw *hw = sensor->hw; + int i; + + if (sensor->id != ST_LSM6DSX_ID_GYRO && + sensor->id != ST_LSM6DSX_ID_ACC) + return; + + /* check if drdy mask is supported in hw */ + if (hw->settings->drdy_mask.addr) + return; + + data = &hw->settings->samples_to_discard[sensor->id]; + for (i = 0; i < ST_LSM6DSX_ODR_LIST_SIZE; i++) { + if (data->val[i].milli_hz == sensor->odr) { + sensor->samples_to_discard = data->val[i].samples; + return; + } + } +} + +int st_lsm6dsx_update_fifo(struct st_lsm6dsx_sensor *sensor, bool enable) +{ + struct st_lsm6dsx_hw *hw = sensor->hw; + u8 fifo_mask; + int err; + + mutex_lock(&hw->conf_lock); + + if (enable) + fifo_mask = hw->fifo_mask | BIT(sensor->id); + else + fifo_mask = hw->fifo_mask & ~BIT(sensor->id); + + if (hw->fifo_mask) { + err = st_lsm6dsx_flush_fifo(hw); + if (err < 0) + goto out; + } + + if (enable) + st_lsm6dsx_update_samples_to_discard(sensor); + + err = st_lsm6dsx_device_set_enable(sensor, enable); + if (err < 0) + goto out; + + err = st_lsm6dsx_set_fifo_odr(sensor, enable); + if (err < 0) + goto out; + + err = st_lsm6dsx_update_decimators(hw); + if (err < 0) + goto out; + + err = st_lsm6dsx_update_watermark(sensor, sensor->watermark); + if (err < 0) + goto out; + + if (fifo_mask) { + err = st_lsm6dsx_resume_fifo(hw); + if (err < 0) + goto out; + } + + hw->fifo_mask = fifo_mask; + +out: + mutex_unlock(&hw->conf_lock); + + return err; +} + +static int st_lsm6dsx_buffer_preenable(struct iio_dev *iio_dev) +{ + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev); + struct st_lsm6dsx_hw *hw = sensor->hw; + + if (!hw->settings->fifo_ops.update_fifo) + return -ENOTSUPP; + + return hw->settings->fifo_ops.update_fifo(sensor, true); +} + +static int st_lsm6dsx_buffer_postdisable(struct iio_dev *iio_dev) +{ + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev); + struct st_lsm6dsx_hw *hw = sensor->hw; + + if (!hw->settings->fifo_ops.update_fifo) + return -ENOTSUPP; + + return hw->settings->fifo_ops.update_fifo(sensor, false); +} + +static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = { + .preenable = st_lsm6dsx_buffer_preenable, + .postdisable = st_lsm6dsx_buffer_postdisable, +}; + +int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw) +{ + int i, ret; + + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) { + if (!hw->iio_devs[i]) + continue; + + ret = devm_iio_kfifo_buffer_setup(hw->dev, hw->iio_devs[i], + &st_lsm6dsx_buffer_ops); + if (ret) + return ret; + } + + return 0; +} |