diff options
Diffstat (limited to 'drivers/iio/accel/sca3300.c')
| -rw-r--r-- | drivers/iio/accel/sca3300.c | 693 |
1 files changed, 693 insertions, 0 deletions
diff --git a/drivers/iio/accel/sca3300.c b/drivers/iio/accel/sca3300.c new file mode 100644 index 000000000..eaa0c9cfd --- /dev/null +++ b/drivers/iio/accel/sca3300.c @@ -0,0 +1,693 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Murata SCA3300 3-axis industrial accelerometer + * + * Copyright (c) 2021 Vaisala Oyj. All rights reserved. + */ + +#include <linux/bitops.h> +#include <linux/crc8.h> +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/spi/spi.h> + +#include <asm/unaligned.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define SCA3300_ALIAS "sca3300" + +#define SCA3300_CRC8_POLYNOMIAL 0x1d + +/* Device mode register */ +#define SCA3300_REG_MODE 0xd +#define SCA3300_MODE_SW_RESET 0x20 + +/* Last register in map */ +#define SCA3300_REG_SELBANK 0x1f + +/* Device status and mask */ +#define SCA3300_REG_STATUS 0x6 +#define SCA3300_STATUS_MASK GENMASK(8, 0) + +/* Device ID */ +#define SCA3300_REG_WHOAMI 0x10 +#define SCA3300_WHOAMI_ID 0x51 +#define SCL3300_WHOAMI_ID 0xC1 + +/* Device return status and mask */ +#define SCA3300_VALUE_RS_ERROR 0x3 +#define SCA3300_MASK_RS_STATUS GENMASK(1, 0) + +#define SCL3300_REG_ANG_CTRL 0x0C +#define SCL3300_ANG_ENABLE 0x1F + +enum sca3300_scan_indexes { + SCA3300_ACC_X = 0, + SCA3300_ACC_Y, + SCA3300_ACC_Z, + SCA3300_TEMP, + SCA3300_INCLI_X, + SCA3300_INCLI_Y, + SCA3300_INCLI_Z, + SCA3300_SCAN_MAX +}; + +/* + * Buffer size max case: + * Three accel channels, two bytes per channel. + * Temperature channel, two bytes. + * Three incli channels, two bytes per channel. + * Timestamp channel, eight bytes. + */ +#define SCA3300_MAX_BUFFER_SIZE (ALIGN(sizeof(s16) * SCA3300_SCAN_MAX, sizeof(s64)) + sizeof(s64)) + +#define SCA3300_ACCEL_CHANNEL(index, reg, axis) { \ + .type = IIO_ACCEL, \ + .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), \ + .info_mask_shared_by_type_available = \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ +} + +#define SCA3300_INCLI_CHANNEL(index, reg, axis) { \ + .type = IIO_INCLI, \ + .address = reg, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ +} + +#define SCA3300_TEMP_CHANNEL(index, reg) { \ + .type = IIO_TEMP, \ + .address = reg, \ + .scan_index = index, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .scan_type = { \ + .sign = 's', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ +} + +static const struct iio_chan_spec sca3300_channels[] = { + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_X, 0x1, X), + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Y, 0x2, Y), + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Z, 0x3, Z), + SCA3300_TEMP_CHANNEL(SCA3300_TEMP, 0x05), + IIO_CHAN_SOFT_TIMESTAMP(4), +}; + +static const int sca3300_lp_freq[] = {70, 10}; +static const int sca3300_lp_freq_map[] = {0, 0, 0, 1}; + +static const int scl3300_lp_freq[] = {40, 70, 10}; +static const int scl3300_lp_freq_map[] = {0, 1, 2}; + +static const int sca3300_accel_scale[][2] = {{0, 370}, {0, 741}, {0, 185}}; +static const int sca3300_accel_scale_map[] = {0, 1, 2, 2}; + +static const int scl3300_accel_scale[][2] = {{0, 167}, {0, 333}, {0, 83}}; +static const int scl3300_accel_scale_map[] = {0, 1, 2}; + +static const int scl3300_incli_scale[][2] = {{0, 5495}}; +static const int scl3300_incli_scale_map[] = {0, 0, 0}; + +static const int sca3300_avail_modes_map[] = {0, 1, 2, 3}; +static const int scl3300_avail_modes_map[] = {0, 1, 3}; + +static const struct iio_chan_spec scl3300_channels[] = { + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_X, 0x1, X), + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Y, 0x2, Y), + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Z, 0x3, Z), + SCA3300_TEMP_CHANNEL(SCA3300_TEMP, 0x05), + SCA3300_INCLI_CHANNEL(SCA3300_INCLI_X, 0x09, X), + SCA3300_INCLI_CHANNEL(SCA3300_INCLI_Y, 0x0A, Y), + SCA3300_INCLI_CHANNEL(SCA3300_INCLI_Z, 0x0B, Z), + IIO_CHAN_SOFT_TIMESTAMP(7), +}; + +static const unsigned long sca3300_scan_masks[] = { + BIT(SCA3300_ACC_X) | BIT(SCA3300_ACC_Y) | BIT(SCA3300_ACC_Z) | + BIT(SCA3300_TEMP), + 0 +}; + +static const unsigned long scl3300_scan_masks[] = { + BIT(SCA3300_ACC_X) | BIT(SCA3300_ACC_Y) | BIT(SCA3300_ACC_Z) | + BIT(SCA3300_TEMP) | + BIT(SCA3300_INCLI_X) | BIT(SCA3300_INCLI_Y) | BIT(SCA3300_INCLI_Z), + 0 +}; + +struct sca3300_chip_info { + const char *name; + const unsigned long *scan_masks; + const struct iio_chan_spec *channels; + u8 num_channels; + u8 num_accel_scales; + const int (*accel_scale)[2]; + const int *accel_scale_map; + const int (*incli_scale)[2]; + const int *incli_scale_map; + u8 num_incli_scales; + u8 num_freqs; + const int *freq_table; + const int *freq_map; + const int *avail_modes_table; + u8 num_avail_modes; + u8 chip_id; + bool angle_supported; +}; + +/** + * struct sca3300_data - device data + * @spi: SPI device structure + * @lock: Data buffer lock + * @chip: Sensor chip specific information + * @buffer: Triggered buffer: + * -SCA3300: 4 channel 16-bit data + 64-bit timestamp + * -SCL3300: 7 channel 16-bit data + 64-bit timestamp + * @txbuf: Transmit buffer + * @rxbuf: Receive buffer + */ +struct sca3300_data { + struct spi_device *spi; + struct mutex lock; + const struct sca3300_chip_info *chip; + u8 buffer[SCA3300_MAX_BUFFER_SIZE] __aligned(sizeof(s64)); + u8 txbuf[4] __aligned(IIO_DMA_MINALIGN); + u8 rxbuf[4]; +}; + +static const struct sca3300_chip_info sca3300_chip_tbl[] = { + { + .name = "sca3300", + .scan_masks = sca3300_scan_masks, + .channels = sca3300_channels, + .num_channels = ARRAY_SIZE(sca3300_channels), + .num_accel_scales = ARRAY_SIZE(sca3300_accel_scale)*2, + .accel_scale = sca3300_accel_scale, + .accel_scale_map = sca3300_accel_scale_map, + .num_freqs = ARRAY_SIZE(sca3300_lp_freq), + .freq_table = sca3300_lp_freq, + .freq_map = sca3300_lp_freq_map, + .avail_modes_table = sca3300_avail_modes_map, + .num_avail_modes = 4, + .chip_id = SCA3300_WHOAMI_ID, + .angle_supported = false, + }, + { + .name = "scl3300", + .scan_masks = scl3300_scan_masks, + .channels = scl3300_channels, + .num_channels = ARRAY_SIZE(scl3300_channels), + .num_accel_scales = ARRAY_SIZE(scl3300_accel_scale)*2, + .accel_scale = scl3300_accel_scale, + .accel_scale_map = scl3300_accel_scale_map, + .incli_scale = scl3300_incli_scale, + .incli_scale_map = scl3300_incli_scale_map, + .num_incli_scales = ARRAY_SIZE(scl3300_incli_scale)*2, + .num_freqs = ARRAY_SIZE(scl3300_lp_freq), + .freq_table = scl3300_lp_freq, + .freq_map = scl3300_lp_freq_map, + .avail_modes_table = scl3300_avail_modes_map, + .num_avail_modes = 3, + .chip_id = SCL3300_WHOAMI_ID, + .angle_supported = true, + }, +}; + +DECLARE_CRC8_TABLE(sca3300_crc_table); + +static int sca3300_transfer(struct sca3300_data *sca_data, int *val) +{ + /* Consecutive requests min. 10 us delay (Datasheet section 5.1.2) */ + struct spi_delay delay = { .value = 10, .unit = SPI_DELAY_UNIT_USECS }; + int32_t ret; + int rs; + u8 crc; + struct spi_transfer xfers[2] = { + { + .tx_buf = sca_data->txbuf, + .len = ARRAY_SIZE(sca_data->txbuf), + .delay = delay, + .cs_change = 1, + }, + { + .rx_buf = sca_data->rxbuf, + .len = ARRAY_SIZE(sca_data->rxbuf), + .delay = delay, + } + }; + + /* inverted crc value as described in device data sheet */ + crc = ~crc8(sca3300_crc_table, &sca_data->txbuf[0], 3, CRC8_INIT_VALUE); + sca_data->txbuf[3] = crc; + + ret = spi_sync_transfer(sca_data->spi, xfers, ARRAY_SIZE(xfers)); + if (ret) { + dev_err(&sca_data->spi->dev, + "transfer error, error: %d\n", ret); + return -EIO; + } + + crc = ~crc8(sca3300_crc_table, &sca_data->rxbuf[0], 3, CRC8_INIT_VALUE); + if (sca_data->rxbuf[3] != crc) { + dev_err(&sca_data->spi->dev, "CRC checksum mismatch"); + return -EIO; + } + + /* get return status */ + rs = sca_data->rxbuf[0] & SCA3300_MASK_RS_STATUS; + if (rs == SCA3300_VALUE_RS_ERROR) + ret = -EINVAL; + + *val = sign_extend32(get_unaligned_be16(&sca_data->rxbuf[1]), 15); + + return ret; +} + +static int sca3300_error_handler(struct sca3300_data *sca_data) +{ + int ret; + int val; + + mutex_lock(&sca_data->lock); + sca_data->txbuf[0] = SCA3300_REG_STATUS << 2; + ret = sca3300_transfer(sca_data, &val); + mutex_unlock(&sca_data->lock); + /* + * Return status error is cleared after reading status register once, + * expect EINVAL here. + */ + if (ret != -EINVAL) { + dev_err(&sca_data->spi->dev, + "error reading device status: %d\n", ret); + return ret; + } + + dev_err(&sca_data->spi->dev, "device status: 0x%lx\n", + val & SCA3300_STATUS_MASK); + + return 0; +} + +static int sca3300_read_reg(struct sca3300_data *sca_data, u8 reg, int *val) +{ + int ret; + + mutex_lock(&sca_data->lock); + sca_data->txbuf[0] = reg << 2; + ret = sca3300_transfer(sca_data, val); + mutex_unlock(&sca_data->lock); + if (ret != -EINVAL) + return ret; + + return sca3300_error_handler(sca_data); +} + +static int sca3300_write_reg(struct sca3300_data *sca_data, u8 reg, int val) +{ + int reg_val = 0; + int ret; + + mutex_lock(&sca_data->lock); + /* BIT(7) for write operation */ + sca_data->txbuf[0] = BIT(7) | (reg << 2); + put_unaligned_be16(val, &sca_data->txbuf[1]); + ret = sca3300_transfer(sca_data, ®_val); + mutex_unlock(&sca_data->lock); + if (ret != -EINVAL) + return ret; + + return sca3300_error_handler(sca_data); +} + +static int sca3300_set_op_mode(struct sca3300_data *sca_data, int index) +{ + if ((index < 0) || (index >= sca_data->chip->num_avail_modes)) + return -EINVAL; + + return sca3300_write_reg(sca_data, SCA3300_REG_MODE, + sca_data->chip->avail_modes_table[index]); +} + +static int sca3300_get_op_mode(struct sca3300_data *sca_data, int *index) +{ + int reg_val; + int ret; + int i; + + ret = sca3300_read_reg(sca_data, SCA3300_REG_MODE, ®_val); + if (ret) + return ret; + + for (i = 0; i < sca_data->chip->num_avail_modes; i++) { + if (sca_data->chip->avail_modes_table[i] == reg_val) + break; + } + if (i == sca_data->chip->num_avail_modes) + return -EINVAL; + + *index = i; + return 0; +} + +static int sca3300_set_frequency(struct sca3300_data *data, int val) +{ + const struct sca3300_chip_info *chip = data->chip; + unsigned int index; + int *opmode_scale; + int *new_scale; + unsigned int i; + + if (sca3300_get_op_mode(data, &index)) + return -EINVAL; + + /* + * Find a mode in which the requested sampling frequency is available + * and the scaling currently set is retained. + */ + opmode_scale = (int *)chip->accel_scale[chip->accel_scale_map[index]]; + for (i = 0; i < chip->num_avail_modes; i++) { + new_scale = (int *)chip->accel_scale[chip->accel_scale_map[i]]; + if ((val == chip->freq_table[chip->freq_map[i]]) && + (opmode_scale[1] == new_scale[1]) && + (opmode_scale[0] == new_scale[0])) + break; + } + if (i == chip->num_avail_modes) + return -EINVAL; + + return sca3300_set_op_mode(data, i); +} + +static int sca3300_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct sca3300_data *data = iio_priv(indio_dev); + int index; + int i; + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + if (chan->type != IIO_ACCEL) + return -EINVAL; + /* + * Letting scale take priority over sampling frequency. + * That makes sense given we can only ever end up increasing + * the sampling frequency which is unlikely to be a problem. + */ + for (i = 0; i < data->chip->num_avail_modes; i++) { + index = data->chip->accel_scale_map[i]; + if ((val == data->chip->accel_scale[index][0]) && + (val2 == data->chip->accel_scale[index][1])) + return sca3300_set_op_mode(data, i); + } + return -EINVAL; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + return sca3300_set_frequency(data, val); + default: + return -EINVAL; + } +} + +static int sca3300_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct sca3300_data *data = iio_priv(indio_dev); + int index; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = sca3300_read_reg(data, chan->address, val); + if (ret) + return ret; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + ret = sca3300_get_op_mode(data, &index); + if (ret) + return ret; + switch (chan->type) { + case IIO_INCLI: + index = data->chip->incli_scale_map[index]; + *val = data->chip->incli_scale[index][0]; + *val2 = data->chip->incli_scale[index][1]; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_ACCEL: + index = data->chip->accel_scale_map[index]; + *val = data->chip->accel_scale[index][0]; + *val2 = data->chip->accel_scale[index][1]; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + ret = sca3300_get_op_mode(data, &index); + if (ret) + return ret; + index = data->chip->freq_map[index]; + *val = data->chip->freq_table[index]; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static irqreturn_t sca3300_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct sca3300_data *data = iio_priv(indio_dev); + int bit, ret, val, i = 0; + s16 *channels = (s16 *)data->buffer; + + for_each_set_bit(bit, indio_dev->active_scan_mask, + indio_dev->masklength) { + ret = sca3300_read_reg(data, indio_dev->channels[bit].address, &val); + if (ret) { + dev_err_ratelimited(&data->spi->dev, + "failed to read register, error: %d\n", ret); + /* handled, but bailing out due to errors */ + goto out; + } + channels[i++] = val; + } + + iio_push_to_buffers_with_timestamp(indio_dev, data->buffer, + iio_get_time_ns(indio_dev)); +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +/* + * sca3300_init - Device init sequence. See datasheet rev 2 section + * 4.2 Start-Up Sequence for details. + */ +static int sca3300_init(struct sca3300_data *sca_data, + struct iio_dev *indio_dev) +{ + int value = 0; + int ret; + int i; + + ret = sca3300_write_reg(sca_data, SCA3300_REG_MODE, + SCA3300_MODE_SW_RESET); + if (ret) + return ret; + + /* + * Wait 1ms after SW-reset command. + * Wait for the settling of signal paths, + * 15ms for SCA3300 and 25ms for SCL3300, + */ + usleep_range(26e3, 50e3); + + ret = sca3300_read_reg(sca_data, SCA3300_REG_WHOAMI, &value); + if (ret) + return ret; + + for (i = 0; i < ARRAY_SIZE(sca3300_chip_tbl); i++) { + if (sca3300_chip_tbl[i].chip_id == value) + break; + } + if (i == ARRAY_SIZE(sca3300_chip_tbl)) { + dev_err(&sca_data->spi->dev, "unknown chip id %x\n", value); + return -ENODEV; + } + + sca_data->chip = &sca3300_chip_tbl[i]; + + if (sca_data->chip->angle_supported) { + ret = sca3300_write_reg(sca_data, SCL3300_REG_ANG_CTRL, + SCL3300_ANG_ENABLE); + if (ret) + return ret; + } + + return 0; +} + +static int sca3300_debugfs_reg_access(struct iio_dev *indio_dev, + unsigned int reg, unsigned int writeval, + unsigned int *readval) +{ + struct sca3300_data *data = iio_priv(indio_dev); + int value; + int ret; + + if (reg > SCA3300_REG_SELBANK) + return -EINVAL; + + if (!readval) + return sca3300_write_reg(data, reg, writeval); + + ret = sca3300_read_reg(data, reg, &value); + if (ret) + return ret; + + *readval = value; + + return 0; +} + +static int sca3300_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + struct sca3300_data *data = iio_priv(indio_dev); + switch (mask) { + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_INCLI: + *vals = (const int *)data->chip->incli_scale; + *length = data->chip->num_incli_scales; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + case IIO_ACCEL: + *vals = (const int *)data->chip->accel_scale; + *length = data->chip->num_accel_scales; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + *vals = (const int *)data->chip->freq_table; + *length = data->chip->num_freqs; + *type = IIO_VAL_INT; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static const struct iio_info sca3300_info = { + .read_raw = sca3300_read_raw, + .write_raw = sca3300_write_raw, + .debugfs_reg_access = &sca3300_debugfs_reg_access, + .read_avail = sca3300_read_avail, +}; + +static int sca3300_probe(struct spi_device *spi) +{ + struct sca3300_data *sca_data; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*sca_data)); + if (!indio_dev) + return -ENOMEM; + + sca_data = iio_priv(indio_dev); + mutex_init(&sca_data->lock); + sca_data->spi = spi; + + crc8_populate_msb(sca3300_crc_table, SCA3300_CRC8_POLYNOMIAL); + + indio_dev->info = &sca3300_info; + + ret = sca3300_init(sca_data, indio_dev); + if (ret) { + dev_err(&spi->dev, "failed to init device, error: %d\n", ret); + return ret; + } + + indio_dev->name = sca_data->chip->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = sca_data->chip->channels; + indio_dev->num_channels = sca_data->chip->num_channels; + indio_dev->available_scan_masks = sca_data->chip->scan_masks; + + ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, + iio_pollfunc_store_time, + sca3300_trigger_handler, NULL); + if (ret) { + dev_err(&spi->dev, + "iio triggered buffer setup failed, error: %d\n", ret); + return ret; + } + + ret = devm_iio_device_register(&spi->dev, indio_dev); + if (ret) { + dev_err(&spi->dev, "iio device register failed, error: %d\n", + ret); + } + + return ret; +} + +static const struct of_device_id sca3300_dt_ids[] = { + { .compatible = "murata,sca3300"}, + { .compatible = "murata,scl3300"}, + {} +}; +MODULE_DEVICE_TABLE(of, sca3300_dt_ids); + +static struct spi_driver sca3300_driver = { + .driver = { + .name = SCA3300_ALIAS, + .of_match_table = sca3300_dt_ids, + }, + .probe = sca3300_probe, +}; +module_spi_driver(sca3300_driver); + +MODULE_AUTHOR("Tomas Melin <tomas.melin@vaisala.com>"); +MODULE_DESCRIPTION("Murata SCA3300 SPI Accelerometer"); +MODULE_LICENSE("GPL v2"); |