diff options
Diffstat (limited to 'drivers/iio/gyro/adxrs290.c')
-rw-r--r-- | drivers/iio/gyro/adxrs290.c | 711 |
1 files changed, 711 insertions, 0 deletions
diff --git a/drivers/iio/gyro/adxrs290.c b/drivers/iio/gyro/adxrs290.c new file mode 100644 index 000000000..c7f996339 --- /dev/null +++ b/drivers/iio/gyro/adxrs290.c @@ -0,0 +1,711 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * ADXRS290 SPI Gyroscope Driver + * + * Copyright (C) 2020 Nishant Malpani <nish.malpani25@gmail.com> + * Copyright (C) 2020 Analog Devices, Inc. + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spi/spi.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/trigger.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/trigger_consumer.h> + +#define ADXRS290_ADI_ID 0xAD +#define ADXRS290_MEMS_ID 0x1D +#define ADXRS290_DEV_ID 0x92 + +#define ADXRS290_REG_ADI_ID 0x00 +#define ADXRS290_REG_MEMS_ID 0x01 +#define ADXRS290_REG_DEV_ID 0x02 +#define ADXRS290_REG_REV_ID 0x03 +#define ADXRS290_REG_SN0 0x04 /* Serial Number Registers, 4 bytes */ +#define ADXRS290_REG_DATAX0 0x08 /* Roll Rate o/p Data Regs, 2 bytes */ +#define ADXRS290_REG_DATAY0 0x0A /* Pitch Rate o/p Data Regs, 2 bytes */ +#define ADXRS290_REG_TEMP0 0x0C +#define ADXRS290_REG_POWER_CTL 0x10 +#define ADXRS290_REG_FILTER 0x11 +#define ADXRS290_REG_DATA_RDY 0x12 + +#define ADXRS290_READ BIT(7) +#define ADXRS290_TSM BIT(0) +#define ADXRS290_MEASUREMENT BIT(1) +#define ADXRS290_DATA_RDY_OUT BIT(0) +#define ADXRS290_SYNC_MASK GENMASK(1, 0) +#define ADXRS290_SYNC(x) FIELD_PREP(ADXRS290_SYNC_MASK, x) +#define ADXRS290_LPF_MASK GENMASK(2, 0) +#define ADXRS290_LPF(x) FIELD_PREP(ADXRS290_LPF_MASK, x) +#define ADXRS290_HPF_MASK GENMASK(7, 4) +#define ADXRS290_HPF(x) FIELD_PREP(ADXRS290_HPF_MASK, x) + +#define ADXRS290_READ_REG(reg) (ADXRS290_READ | (reg)) + +#define ADXRS290_MAX_TRANSITION_TIME_MS 100 + +enum adxrs290_mode { + ADXRS290_MODE_STANDBY, + ADXRS290_MODE_MEASUREMENT, +}; + +enum adxrs290_scan_index { + ADXRS290_IDX_X, + ADXRS290_IDX_Y, + ADXRS290_IDX_TEMP, + ADXRS290_IDX_TS, +}; + +struct adxrs290_state { + struct spi_device *spi; + /* Serialize reads and their subsequent processing */ + struct mutex lock; + enum adxrs290_mode mode; + unsigned int lpf_3db_freq_idx; + unsigned int hpf_3db_freq_idx; + struct iio_trigger *dready_trig; + /* Ensure correct alignment of timestamp when present */ + struct { + s16 channels[3]; + s64 ts __aligned(8); + } buffer; +}; + +/* + * Available cut-off frequencies of the low pass filter in Hz. + * The integer part and fractional part are represented separately. + */ +static const int adxrs290_lpf_3db_freq_hz_table[][2] = { + [0] = {480, 0}, + [1] = {320, 0}, + [2] = {160, 0}, + [3] = {80, 0}, + [4] = {56, 600000}, + [5] = {40, 0}, + [6] = {28, 300000}, + [7] = {20, 0}, +}; + +/* + * Available cut-off frequencies of the high pass filter in Hz. + * The integer part and fractional part are represented separately. + */ +static const int adxrs290_hpf_3db_freq_hz_table[][2] = { + [0] = {0, 0}, + [1] = {0, 11000}, + [2] = {0, 22000}, + [3] = {0, 44000}, + [4] = {0, 87000}, + [5] = {0, 175000}, + [6] = {0, 350000}, + [7] = {0, 700000}, + [8] = {1, 400000}, + [9] = {2, 800000}, + [10] = {11, 300000}, +}; + +static int adxrs290_get_rate_data(struct iio_dev *indio_dev, const u8 cmd, int *val) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + int ret = 0; + int temp; + + mutex_lock(&st->lock); + temp = spi_w8r16(st->spi, cmd); + if (temp < 0) { + ret = temp; + goto err_unlock; + } + + *val = sign_extend32(temp, 15); + +err_unlock: + mutex_unlock(&st->lock); + return ret; +} + +static int adxrs290_get_temp_data(struct iio_dev *indio_dev, int *val) +{ + const u8 cmd = ADXRS290_READ_REG(ADXRS290_REG_TEMP0); + struct adxrs290_state *st = iio_priv(indio_dev); + int ret = 0; + int temp; + + mutex_lock(&st->lock); + temp = spi_w8r16(st->spi, cmd); + if (temp < 0) { + ret = temp; + goto err_unlock; + } + + /* extract lower 12 bits temperature reading */ + *val = sign_extend32(temp, 11); + +err_unlock: + mutex_unlock(&st->lock); + return ret; +} + +static int adxrs290_get_3db_freq(struct iio_dev *indio_dev, u8 *val, u8 *val2) +{ + const u8 cmd = ADXRS290_READ_REG(ADXRS290_REG_FILTER); + struct adxrs290_state *st = iio_priv(indio_dev); + int ret = 0; + short temp; + + mutex_lock(&st->lock); + temp = spi_w8r8(st->spi, cmd); + if (temp < 0) { + ret = temp; + goto err_unlock; + } + + *val = FIELD_GET(ADXRS290_LPF_MASK, temp); + *val2 = FIELD_GET(ADXRS290_HPF_MASK, temp); + +err_unlock: + mutex_unlock(&st->lock); + return ret; +} + +static int adxrs290_spi_write_reg(struct spi_device *spi, const u8 reg, + const u8 val) +{ + u8 buf[2]; + + buf[0] = reg; + buf[1] = val; + + return spi_write_then_read(spi, buf, ARRAY_SIZE(buf), NULL, 0); +} + +static int adxrs290_find_match(const int (*freq_tbl)[2], const int n, + const int val, const int val2) +{ + int i; + + for (i = 0; i < n; i++) { + if (freq_tbl[i][0] == val && freq_tbl[i][1] == val2) + return i; + } + + return -EINVAL; +} + +static int adxrs290_set_filter_freq(struct iio_dev *indio_dev, + const unsigned int lpf_idx, + const unsigned int hpf_idx) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + u8 val; + + val = ADXRS290_HPF(hpf_idx) | ADXRS290_LPF(lpf_idx); + + return adxrs290_spi_write_reg(st->spi, ADXRS290_REG_FILTER, val); +} + +static int adxrs290_set_mode(struct iio_dev *indio_dev, enum adxrs290_mode mode) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + int val, ret; + + if (st->mode == mode) + return 0; + + mutex_lock(&st->lock); + + ret = spi_w8r8(st->spi, ADXRS290_READ_REG(ADXRS290_REG_POWER_CTL)); + if (ret < 0) + goto out_unlock; + + val = ret; + + switch (mode) { + case ADXRS290_MODE_STANDBY: + val &= ~ADXRS290_MEASUREMENT; + break; + case ADXRS290_MODE_MEASUREMENT: + val |= ADXRS290_MEASUREMENT; + break; + default: + ret = -EINVAL; + goto out_unlock; + } + + ret = adxrs290_spi_write_reg(st->spi, ADXRS290_REG_POWER_CTL, val); + if (ret < 0) { + dev_err(&st->spi->dev, "unable to set mode: %d\n", ret); + goto out_unlock; + } + + /* update cached mode */ + st->mode = mode; + +out_unlock: + mutex_unlock(&st->lock); + return ret; +} + +static void adxrs290_chip_off_action(void *data) +{ + struct iio_dev *indio_dev = data; + + adxrs290_set_mode(indio_dev, ADXRS290_MODE_STANDBY); +} + +static int adxrs290_initial_setup(struct iio_dev *indio_dev) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + struct spi_device *spi = st->spi; + int ret; + + ret = adxrs290_spi_write_reg(spi, ADXRS290_REG_POWER_CTL, + ADXRS290_MEASUREMENT | ADXRS290_TSM); + if (ret < 0) + return ret; + + st->mode = ADXRS290_MODE_MEASUREMENT; + + return devm_add_action_or_reset(&spi->dev, adxrs290_chip_off_action, + indio_dev); +} + +static int adxrs290_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + unsigned int t; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + switch (chan->type) { + case IIO_ANGL_VEL: + ret = adxrs290_get_rate_data(indio_dev, + ADXRS290_READ_REG(chan->address), + val); + if (ret < 0) + break; + + ret = IIO_VAL_INT; + break; + case IIO_TEMP: + ret = adxrs290_get_temp_data(indio_dev, val); + if (ret < 0) + break; + + ret = IIO_VAL_INT; + break; + default: + ret = -EINVAL; + break; + } + + iio_device_release_direct_mode(indio_dev); + return ret; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_ANGL_VEL: + /* 1 LSB = 0.005 degrees/sec */ + *val = 0; + *val2 = 87266; + return IIO_VAL_INT_PLUS_NANO; + case IIO_TEMP: + /* 1 LSB = 0.1 degrees Celsius */ + *val = 100; + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + switch (chan->type) { + case IIO_ANGL_VEL: + t = st->lpf_3db_freq_idx; + *val = adxrs290_lpf_3db_freq_hz_table[t][0]; + *val2 = adxrs290_lpf_3db_freq_hz_table[t][1]; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY: + switch (chan->type) { + case IIO_ANGL_VEL: + t = st->hpf_3db_freq_idx; + *val = adxrs290_hpf_3db_freq_hz_table[t][0]; + *val2 = adxrs290_hpf_3db_freq_hz_table[t][1]; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } + } + + return -EINVAL; +} + +static int adxrs290_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + int ret, lpf_idx, hpf_idx; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + switch (mask) { + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + lpf_idx = adxrs290_find_match(adxrs290_lpf_3db_freq_hz_table, + ARRAY_SIZE(adxrs290_lpf_3db_freq_hz_table), + val, val2); + if (lpf_idx < 0) { + ret = -EINVAL; + break; + } + + /* caching the updated state of the low-pass filter */ + st->lpf_3db_freq_idx = lpf_idx; + /* retrieving the current state of the high-pass filter */ + hpf_idx = st->hpf_3db_freq_idx; + ret = adxrs290_set_filter_freq(indio_dev, lpf_idx, hpf_idx); + break; + + case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY: + hpf_idx = adxrs290_find_match(adxrs290_hpf_3db_freq_hz_table, + ARRAY_SIZE(adxrs290_hpf_3db_freq_hz_table), + val, val2); + if (hpf_idx < 0) { + ret = -EINVAL; + break; + } + + /* caching the updated state of the high-pass filter */ + st->hpf_3db_freq_idx = hpf_idx; + /* retrieving the current state of the low-pass filter */ + lpf_idx = st->lpf_3db_freq_idx; + ret = adxrs290_set_filter_freq(indio_dev, lpf_idx, hpf_idx); + break; + + default: + ret = -EINVAL; + break; + } + + iio_device_release_direct_mode(indio_dev); + return ret; +} + +static int adxrs290_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + *vals = (const int *)adxrs290_lpf_3db_freq_hz_table; + *type = IIO_VAL_INT_PLUS_MICRO; + /* Values are stored in a 2D matrix */ + *length = ARRAY_SIZE(adxrs290_lpf_3db_freq_hz_table) * 2; + + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY: + *vals = (const int *)adxrs290_hpf_3db_freq_hz_table; + *type = IIO_VAL_INT_PLUS_MICRO; + /* Values are stored in a 2D matrix */ + *length = ARRAY_SIZE(adxrs290_hpf_3db_freq_hz_table) * 2; + + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static int adxrs290_reg_access_rw(struct spi_device *spi, unsigned int reg, + unsigned int *readval) +{ + int ret; + + ret = spi_w8r8(spi, ADXRS290_READ_REG(reg)); + if (ret < 0) + return ret; + + *readval = ret; + + return 0; +} + +static int adxrs290_reg_access(struct iio_dev *indio_dev, unsigned int reg, + unsigned int writeval, unsigned int *readval) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + + if (readval) + return adxrs290_reg_access_rw(st->spi, reg, readval); + else + return adxrs290_spi_write_reg(st->spi, reg, writeval); +} + +static int adxrs290_data_rdy_trigger_set_state(struct iio_trigger *trig, + bool state) +{ + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); + struct adxrs290_state *st = iio_priv(indio_dev); + int ret; + u8 val; + + val = state ? ADXRS290_SYNC(ADXRS290_DATA_RDY_OUT) : 0; + + ret = adxrs290_spi_write_reg(st->spi, ADXRS290_REG_DATA_RDY, val); + if (ret < 0) + dev_err(&st->spi->dev, "failed to start data rdy interrupt\n"); + + return ret; +} + +static int adxrs290_reset_trig(struct iio_trigger *trig) +{ + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); + int val; + + /* + * Data ready interrupt is reset after a read of the data registers. + * Here, we only read the 16b DATAY registers as that marks the end of + * a read of the data registers and initiates a reset for the interrupt + * line. + */ + adxrs290_get_rate_data(indio_dev, + ADXRS290_READ_REG(ADXRS290_REG_DATAY0), &val); + + return 0; +} + +static const struct iio_trigger_ops adxrs290_trigger_ops = { + .set_trigger_state = &adxrs290_data_rdy_trigger_set_state, + .validate_device = &iio_trigger_validate_own_device, + .try_reenable = &adxrs290_reset_trig, +}; + +static irqreturn_t adxrs290_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct adxrs290_state *st = iio_priv(indio_dev); + u8 tx = ADXRS290_READ_REG(ADXRS290_REG_DATAX0); + int ret; + + mutex_lock(&st->lock); + + /* exercise a bulk data capture starting from reg DATAX0... */ + ret = spi_write_then_read(st->spi, &tx, sizeof(tx), st->buffer.channels, + sizeof(st->buffer.channels)); + if (ret < 0) + goto out_unlock_notify; + + iio_push_to_buffers_with_timestamp(indio_dev, &st->buffer, + pf->timestamp); + +out_unlock_notify: + mutex_unlock(&st->lock); + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +#define ADXRS290_ANGL_VEL_CHANNEL(reg, axis) { \ + .type = IIO_ANGL_VEL, \ + .address = reg, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \ + BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \ + .info_mask_shared_by_type_available = \ + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \ + BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \ + .scan_index = ADXRS290_IDX_##axis, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_LE, \ + }, \ +} + +static const struct iio_chan_spec adxrs290_channels[] = { + ADXRS290_ANGL_VEL_CHANNEL(ADXRS290_REG_DATAX0, X), + ADXRS290_ANGL_VEL_CHANNEL(ADXRS290_REG_DATAY0, Y), + { + .type = IIO_TEMP, + .address = ADXRS290_REG_TEMP0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .scan_index = ADXRS290_IDX_TEMP, + .scan_type = { + .sign = 's', + .realbits = 12, + .storagebits = 16, + .endianness = IIO_LE, + }, + }, + IIO_CHAN_SOFT_TIMESTAMP(ADXRS290_IDX_TS), +}; + +static const unsigned long adxrs290_avail_scan_masks[] = { + BIT(ADXRS290_IDX_X) | BIT(ADXRS290_IDX_Y) | BIT(ADXRS290_IDX_TEMP), + 0 +}; + +static const struct iio_info adxrs290_info = { + .read_raw = &adxrs290_read_raw, + .write_raw = &adxrs290_write_raw, + .read_avail = &adxrs290_read_avail, + .debugfs_reg_access = &adxrs290_reg_access, +}; + +static int adxrs290_probe_trigger(struct iio_dev *indio_dev) +{ + struct adxrs290_state *st = iio_priv(indio_dev); + int ret; + + if (!st->spi->irq) { + dev_info(&st->spi->dev, "no irq, using polling\n"); + return 0; + } + + st->dready_trig = devm_iio_trigger_alloc(&st->spi->dev, "%s-dev%d", + indio_dev->name, + indio_dev->id); + if (!st->dready_trig) + return -ENOMEM; + + st->dready_trig->dev.parent = &st->spi->dev; + st->dready_trig->ops = &adxrs290_trigger_ops; + iio_trigger_set_drvdata(st->dready_trig, indio_dev); + + ret = devm_request_irq(&st->spi->dev, st->spi->irq, + &iio_trigger_generic_data_rdy_poll, + IRQF_ONESHOT, "adxrs290_irq", st->dready_trig); + if (ret < 0) + return dev_err_probe(&st->spi->dev, ret, + "request irq %d failed\n", st->spi->irq); + + ret = devm_iio_trigger_register(&st->spi->dev, st->dready_trig); + if (ret) { + dev_err(&st->spi->dev, "iio trigger register failed\n"); + return ret; + } + + indio_dev->trig = iio_trigger_get(st->dready_trig); + + return 0; +} + +static int adxrs290_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct adxrs290_state *st; + u8 val, val2; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi = spi; + + indio_dev->name = "adxrs290"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = adxrs290_channels; + indio_dev->num_channels = ARRAY_SIZE(adxrs290_channels); + indio_dev->info = &adxrs290_info; + indio_dev->available_scan_masks = adxrs290_avail_scan_masks; + + mutex_init(&st->lock); + + val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_ADI_ID)); + if (val != ADXRS290_ADI_ID) { + dev_err(&spi->dev, "Wrong ADI ID 0x%02x\n", val); + return -ENODEV; + } + + val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_MEMS_ID)); + if (val != ADXRS290_MEMS_ID) { + dev_err(&spi->dev, "Wrong MEMS ID 0x%02x\n", val); + return -ENODEV; + } + + val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_DEV_ID)); + if (val != ADXRS290_DEV_ID) { + dev_err(&spi->dev, "Wrong DEV ID 0x%02x\n", val); + return -ENODEV; + } + + /* default mode the gyroscope starts in */ + st->mode = ADXRS290_MODE_STANDBY; + + /* switch to measurement mode and switch on the temperature sensor */ + ret = adxrs290_initial_setup(indio_dev); + if (ret < 0) + return ret; + + /* max transition time to measurement mode */ + msleep(ADXRS290_MAX_TRANSITION_TIME_MS); + + ret = adxrs290_get_3db_freq(indio_dev, &val, &val2); + if (ret < 0) + return ret; + + st->lpf_3db_freq_idx = val; + st->hpf_3db_freq_idx = val2; + + ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, + &iio_pollfunc_store_time, + &adxrs290_trigger_handler, NULL); + if (ret < 0) + return dev_err_probe(&spi->dev, ret, + "iio triggered buffer setup failed\n"); + + ret = adxrs290_probe_trigger(indio_dev); + if (ret < 0) + return ret; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id adxrs290_of_match[] = { + { .compatible = "adi,adxrs290" }, + { } +}; +MODULE_DEVICE_TABLE(of, adxrs290_of_match); + +static struct spi_driver adxrs290_driver = { + .driver = { + .name = "adxrs290", + .of_match_table = adxrs290_of_match, + }, + .probe = adxrs290_probe, +}; +module_spi_driver(adxrs290_driver); + +MODULE_AUTHOR("Nishant Malpani <nish.malpani25@gmail.com>"); +MODULE_DESCRIPTION("Analog Devices ADXRS290 Gyroscope SPI driver"); +MODULE_LICENSE("GPL"); |