--- /dev/null
+/*
+ * BMI160 - Bosch IMU (accel, gyro plus external magnetometer)
+ *
+ * Copyright (c) 2016, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO core driver for BMI160, with support for I2C/SPI busses
+ *
+ * TODO: magnetometer, interrupts, hardware FIFO
+ */
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+
+#include "bmi160.h"
+
+#define BMI160_REG_CHIP_ID 0x00
+#define BMI160_CHIP_ID_VAL 0xD1
+
+#define BMI160_REG_PMU_STATUS 0x03
+
+/* X axis data low byte address, the rest can be obtained using axis offset */
+#define BMI160_REG_DATA_MAGN_XOUT_L 0x04
+#define BMI160_REG_DATA_GYRO_XOUT_L 0x0C
+#define BMI160_REG_DATA_ACCEL_XOUT_L 0x12
+
+#define BMI160_REG_ACCEL_CONFIG 0x40
+#define BMI160_ACCEL_CONFIG_ODR_MASK GENMASK(3, 0)
+#define BMI160_ACCEL_CONFIG_BWP_MASK GENMASK(6, 4)
+
+#define BMI160_REG_ACCEL_RANGE 0x41
+#define BMI160_ACCEL_RANGE_2G 0x03
+#define BMI160_ACCEL_RANGE_4G 0x05
+#define BMI160_ACCEL_RANGE_8G 0x08
+#define BMI160_ACCEL_RANGE_16G 0x0C
+
+#define BMI160_REG_GYRO_CONFIG 0x42
+#define BMI160_GYRO_CONFIG_ODR_MASK GENMASK(3, 0)
+#define BMI160_GYRO_CONFIG_BWP_MASK GENMASK(5, 4)
+
+#define BMI160_REG_GYRO_RANGE 0x43
+#define BMI160_GYRO_RANGE_2000DPS 0x00
+#define BMI160_GYRO_RANGE_1000DPS 0x01
+#define BMI160_GYRO_RANGE_500DPS 0x02
+#define BMI160_GYRO_RANGE_250DPS 0x03
+#define BMI160_GYRO_RANGE_125DPS 0x04
+
+#define BMI160_REG_CMD 0x7E
+#define BMI160_CMD_ACCEL_PM_SUSPEND 0x10
+#define BMI160_CMD_ACCEL_PM_NORMAL 0x11
+#define BMI160_CMD_ACCEL_PM_LOW_POWER 0x12
+#define BMI160_CMD_GYRO_PM_SUSPEND 0x14
+#define BMI160_CMD_GYRO_PM_NORMAL 0x15
+#define BMI160_CMD_GYRO_PM_FAST_STARTUP 0x17
+#define BMI160_CMD_SOFTRESET 0xB6
+
+#define BMI160_REG_DUMMY 0x7F
+
+#define BMI160_ACCEL_PMU_MIN_USLEEP 3200
+#define BMI160_ACCEL_PMU_MAX_USLEEP 3800
+#define BMI160_GYRO_PMU_MIN_USLEEP 55000
+#define BMI160_GYRO_PMU_MAX_USLEEP 80000
+#define BMI160_SOFTRESET_USLEEP 1000
+
+#define BMI160_CHANNEL(_type, _axis, _index) { \
+ .type = _type, \
+ .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_SAMP_FREQ), \
+ .scan_index = _index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_LE, \
+ }, \
+}
+
+/* scan indexes follow DATA register order */
+enum bmi160_scan_axis {
+ BMI160_SCAN_EXT_MAGN_X = 0,
+ BMI160_SCAN_EXT_MAGN_Y,
+ BMI160_SCAN_EXT_MAGN_Z,
+ BMI160_SCAN_RHALL,
+ BMI160_SCAN_GYRO_X,
+ BMI160_SCAN_GYRO_Y,
+ BMI160_SCAN_GYRO_Z,
+ BMI160_SCAN_ACCEL_X,
+ BMI160_SCAN_ACCEL_Y,
+ BMI160_SCAN_ACCEL_Z,
+ BMI160_SCAN_TIMESTAMP,
+};
+
+enum bmi160_sensor_type {
+ BMI160_ACCEL = 0,
+ BMI160_GYRO,
+ BMI160_EXT_MAGN,
+ BMI160_NUM_SENSORS /* must be last */
+};
+
+struct bmi160_data {
+ struct regmap *regmap;
+};
+
+const struct regmap_config bmi160_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+EXPORT_SYMBOL(bmi160_regmap_config);
+
+struct bmi160_regs {
+ u8 data; /* LSB byte register for X-axis */
+ u8 config;
+ u8 config_odr_mask;
+ u8 config_bwp_mask;
+ u8 range;
+ u8 pmu_cmd_normal;
+ u8 pmu_cmd_suspend;
+};
+
+static struct bmi160_regs bmi160_regs[] = {
+ [BMI160_ACCEL] = {
+ .data = BMI160_REG_DATA_ACCEL_XOUT_L,
+ .config = BMI160_REG_ACCEL_CONFIG,
+ .config_odr_mask = BMI160_ACCEL_CONFIG_ODR_MASK,
+ .config_bwp_mask = BMI160_ACCEL_CONFIG_BWP_MASK,
+ .range = BMI160_REG_ACCEL_RANGE,
+ .pmu_cmd_normal = BMI160_CMD_ACCEL_PM_NORMAL,
+ .pmu_cmd_suspend = BMI160_CMD_ACCEL_PM_SUSPEND,
+ },
+ [BMI160_GYRO] = {
+ .data = BMI160_REG_DATA_GYRO_XOUT_L,
+ .config = BMI160_REG_GYRO_CONFIG,
+ .config_odr_mask = BMI160_GYRO_CONFIG_ODR_MASK,
+ .config_bwp_mask = BMI160_GYRO_CONFIG_BWP_MASK,
+ .range = BMI160_REG_GYRO_RANGE,
+ .pmu_cmd_normal = BMI160_CMD_GYRO_PM_NORMAL,
+ .pmu_cmd_suspend = BMI160_CMD_GYRO_PM_SUSPEND,
+ },
+};
+
+struct bmi160_pmu_time {
+ unsigned long min;
+ unsigned long max;
+};
+
+static struct bmi160_pmu_time bmi160_pmu_time[] = {
+ [BMI160_ACCEL] = {
+ .min = BMI160_ACCEL_PMU_MIN_USLEEP,
+ .max = BMI160_ACCEL_PMU_MAX_USLEEP
+ },
+ [BMI160_GYRO] = {
+ .min = BMI160_GYRO_PMU_MIN_USLEEP,
+ .max = BMI160_GYRO_PMU_MIN_USLEEP,
+ },
+};
+
+struct bmi160_scale {
+ u8 bits;
+ int uscale;
+};
+
+struct bmi160_odr {
+ u8 bits;
+ int odr;
+ int uodr;
+};
+
+static const struct bmi160_scale bmi160_accel_scale[] = {
+ { BMI160_ACCEL_RANGE_2G, 598},
+ { BMI160_ACCEL_RANGE_4G, 1197},
+ { BMI160_ACCEL_RANGE_8G, 2394},
+ { BMI160_ACCEL_RANGE_16G, 4788},
+};
+
+static const struct bmi160_scale bmi160_gyro_scale[] = {
+ { BMI160_GYRO_RANGE_2000DPS, 1065},
+ { BMI160_GYRO_RANGE_1000DPS, 532},
+ { BMI160_GYRO_RANGE_500DPS, 266},
+ { BMI160_GYRO_RANGE_250DPS, 133},
+ { BMI160_GYRO_RANGE_125DPS, 66},
+};
+
+struct bmi160_scale_item {
+ const struct bmi160_scale *tbl;
+ int num;
+};
+
+static const struct bmi160_scale_item bmi160_scale_table[] = {
+ [BMI160_ACCEL] = {
+ .tbl = bmi160_accel_scale,
+ .num = ARRAY_SIZE(bmi160_accel_scale),
+ },
+ [BMI160_GYRO] = {
+ .tbl = bmi160_gyro_scale,
+ .num = ARRAY_SIZE(bmi160_gyro_scale),
+ },
+};
+
+static const struct bmi160_odr bmi160_accel_odr[] = {
+ {0x01, 0, 78125},
+ {0x02, 1, 5625},
+ {0x03, 3, 125},
+ {0x04, 6, 25},
+ {0x05, 12, 5},
+ {0x06, 25, 0},
+ {0x07, 50, 0},
+ {0x08, 100, 0},
+ {0x09, 200, 0},
+ {0x0A, 400, 0},
+ {0x0B, 800, 0},
+ {0x0C, 1600, 0},
+};
+
+static const struct bmi160_odr bmi160_gyro_odr[] = {
+ {0x06, 25, 0},
+ {0x07, 50, 0},
+ {0x08, 100, 0},
+ {0x09, 200, 0},
+ {0x0A, 400, 0},
+ {0x0B, 8000, 0},
+ {0x0C, 1600, 0},
+ {0x0D, 3200, 0},
+};
+
+struct bmi160_odr_item {
+ const struct bmi160_odr *tbl;
+ int num;
+};
+
+static const struct bmi160_odr_item bmi160_odr_table[] = {
+ [BMI160_ACCEL] = {
+ .tbl = bmi160_accel_odr,
+ .num = ARRAY_SIZE(bmi160_accel_odr),
+ },
+ [BMI160_GYRO] = {
+ .tbl = bmi160_gyro_odr,
+ .num = ARRAY_SIZE(bmi160_gyro_odr),
+ },
+};
+
+static const struct iio_chan_spec bmi160_channels[] = {
+ BMI160_CHANNEL(IIO_ACCEL, X, BMI160_SCAN_ACCEL_X),
+ BMI160_CHANNEL(IIO_ACCEL, Y, BMI160_SCAN_ACCEL_Y),
+ BMI160_CHANNEL(IIO_ACCEL, Z, BMI160_SCAN_ACCEL_Z),
+ BMI160_CHANNEL(IIO_ANGL_VEL, X, BMI160_SCAN_GYRO_X),
+ BMI160_CHANNEL(IIO_ANGL_VEL, Y, BMI160_SCAN_GYRO_Y),
+ BMI160_CHANNEL(IIO_ANGL_VEL, Z, BMI160_SCAN_GYRO_Z),
+ IIO_CHAN_SOFT_TIMESTAMP(BMI160_SCAN_TIMESTAMP),
+};
+
+static enum bmi160_sensor_type bmi160_to_sensor(enum iio_chan_type iio_type)
+{
+ switch (iio_type) {
+ case IIO_ACCEL:
+ return BMI160_ACCEL;
+ case IIO_ANGL_VEL:
+ return BMI160_GYRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int bmi160_set_mode(struct bmi160_data *data, enum bmi160_sensor_type t,
+ bool mode)
+{
+ int ret;
+ u8 cmd;
+
+ if (mode)
+ cmd = bmi160_regs[t].pmu_cmd_normal;
+ else
+ cmd = bmi160_regs[t].pmu_cmd_suspend;
+
+ ret = regmap_write(data->regmap, BMI160_REG_CMD, cmd);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(bmi160_pmu_time[t].min, bmi160_pmu_time[t].max);
+
+ return 0;
+}
+
+static
+int bmi160_set_scale(struct bmi160_data *data, enum bmi160_sensor_type t,
+ int uscale)
+{
+ int i;
+
+ for (i = 0; i < bmi160_scale_table[t].num; i++)
+ if (bmi160_scale_table[t].tbl[i].uscale == uscale)
+ break;
+
+ if (i == bmi160_scale_table[t].num)
+ return -EINVAL;
+
+ return regmap_write(data->regmap, bmi160_regs[t].range,
+ bmi160_scale_table[t].tbl[i].bits);
+}
+
+static
+int bmi160_get_scale(struct bmi160_data *data, enum bmi160_sensor_type t,
+ int *uscale)
+{
+ int i, ret, val;
+
+ ret = regmap_read(data->regmap, bmi160_regs[t].range, &val);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < bmi160_scale_table[t].num; i++)
+ if (bmi160_scale_table[t].tbl[i].bits == val) {
+ *uscale = bmi160_scale_table[t].tbl[i].uscale;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int bmi160_get_data(struct bmi160_data *data, int chan_type,
+ int axis, int *val)
+{
+ u8 reg;
+ int ret;
+ __le16 sample;
+ enum bmi160_sensor_type t = bmi160_to_sensor(chan_type);
+
+ reg = bmi160_regs[t].data + (axis - IIO_MOD_X) * sizeof(__le16);
+
+ ret = regmap_bulk_read(data->regmap, reg, &sample, sizeof(__le16));
+ if (ret < 0)
+ return ret;
+
+ *val = sign_extend32(le16_to_cpu(sample), 15);
+
+ return 0;
+}
+
+static
+int bmi160_set_odr(struct bmi160_data *data, enum bmi160_sensor_type t,
+ int odr, int uodr)
+{
+ int i;
+
+ for (i = 0; i < bmi160_odr_table[t].num; i++)
+ if (bmi160_odr_table[t].tbl[i].odr == odr &&
+ bmi160_odr_table[t].tbl[i].uodr == uodr)
+ break;
+
+ if (i >= bmi160_odr_table[t].num)
+ return -EINVAL;
+
+ return regmap_update_bits(data->regmap,
+ bmi160_regs[t].config,
+ bmi160_odr_table[t].tbl[i].bits,
+ bmi160_regs[t].config_odr_mask);
+}
+
+static int bmi160_get_odr(struct bmi160_data *data, enum bmi160_sensor_type t,
+ int *odr, int *uodr)
+{
+ int i, val, ret;
+
+ ret = regmap_read(data->regmap, bmi160_regs[t].config, &val);
+ if (ret < 0)
+ return ret;
+
+ val &= bmi160_regs[t].config_odr_mask;
+
+ for (i = 0; i < bmi160_odr_table[t].num; i++)
+ if (val == bmi160_odr_table[t].tbl[i].bits)
+ break;
+
+ if (i >= bmi160_odr_table[t].num)
+ return -EINVAL;
+
+ *odr = bmi160_odr_table[t].tbl[i].odr;
+ *uodr = bmi160_odr_table[t].tbl[i].uodr;
+
+ return 0;
+}
+
+static irqreturn_t bmi160_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct bmi160_data *data = iio_priv(indio_dev);
+ s16 buf[16]; /* 3 sens x 3 axis x s16 + 3 x s16 pad + 4 x s16 tstamp */
+ int i, ret, j = 0, base = BMI160_REG_DATA_MAGN_XOUT_L;
+ __le16 sample;
+
+ for_each_set_bit(i, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ ret = regmap_bulk_read(data->regmap, base + i * sizeof(__le16),
+ &sample, sizeof(__le16));
+ if (ret < 0)
+ goto done;
+ buf[j++] = sample;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+static int bmi160_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ struct bmi160_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = bmi160_get_data(data, chan->type, chan->channel2, val);
+ if (ret < 0)
+ return ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ ret = bmi160_get_scale(data,
+ bmi160_to_sensor(chan->type), val2);
+ return ret < 0 ? ret : IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = bmi160_get_odr(data, bmi160_to_sensor(chan->type),
+ val, val2);
+ return ret < 0 ? ret : IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int bmi160_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct bmi160_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ return bmi160_set_scale(data,
+ bmi160_to_sensor(chan->type), val2);
+ break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return bmi160_set_odr(data, bmi160_to_sensor(chan->type),
+ val, val2);
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct iio_info bmi160_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = bmi160_read_raw,
+ .write_raw = bmi160_write_raw,
+};
+
+static const char *bmi160_match_acpi_device(struct device *dev)
+{
+ const struct acpi_device_id *id;
+
+ id = acpi_match_device(dev->driver->acpi_match_table, dev);
+ if (!id)
+ return NULL;
+
+ return dev_name(dev);
+}
+
+static int bmi160_chip_init(struct bmi160_data *data, bool use_spi)
+{
+ int ret;
+ unsigned int val;
+ struct device *dev = regmap_get_device(data->regmap);
+
+ ret = regmap_write(data->regmap, BMI160_REG_CMD, BMI160_CMD_SOFTRESET);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(BMI160_SOFTRESET_USLEEP, BMI160_SOFTRESET_USLEEP + 1);
+
+ /*
+ * CS rising edge is needed before starting SPI, so do a dummy read
+ * See Section 3.2.1, page 86 of the datasheet
+ */
+ if (use_spi) {
+ ret = regmap_read(data->regmap, BMI160_REG_DUMMY, &val);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = regmap_read(data->regmap, BMI160_REG_CHIP_ID, &val);
+ if (ret < 0) {
+ dev_err(dev, "Error reading chip id\n");
+ return ret;
+ }
+ if (val != BMI160_CHIP_ID_VAL) {
+ dev_err(dev, "Wrong chip id, got %x expected %x\n",
+ val, BMI160_CHIP_ID_VAL);
+ return -ENODEV;
+ }
+
+ ret = bmi160_set_mode(data, BMI160_ACCEL, true);
+ if (ret < 0)
+ return ret;
+
+ ret = bmi160_set_mode(data, BMI160_GYRO, true);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static void bmi160_chip_uninit(struct bmi160_data *data)
+{
+ bmi160_set_mode(data, BMI160_GYRO, false);
+ bmi160_set_mode(data, BMI160_ACCEL, false);
+}
+
+int bmi160_core_probe(struct device *dev, struct regmap *regmap,
+ const char *name, bool use_spi)
+{
+ struct iio_dev *indio_dev;
+ struct bmi160_data *data;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ dev_set_drvdata(dev, indio_dev);
+ data->regmap = regmap;
+
+ ret = bmi160_chip_init(data, use_spi);
+ if (ret < 0)
+ return ret;
+
+ if (!name && ACPI_HANDLE(dev))
+ name = bmi160_match_acpi_device(dev);
+
+ indio_dev->dev.parent = dev;
+ indio_dev->channels = bmi160_channels;
+ indio_dev->num_channels = ARRAY_SIZE(bmi160_channels);
+ indio_dev->name = name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &bmi160_info;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ bmi160_trigger_handler, NULL);
+ if (ret < 0)
+ goto uninit;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ goto buffer_cleanup;
+
+ return 0;
+buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+uninit:
+ bmi160_chip_uninit(data);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bmi160_core_probe);
+
+void bmi160_core_remove(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct bmi160_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+ bmi160_chip_uninit(data);
+}
+EXPORT_SYMBOL_GPL(bmi160_core_remove);
+
+MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com");
+MODULE_DESCRIPTION("Bosch BMI160 driver");
+MODULE_LICENSE("GPL v2");
projects / linux-beck.git / commitdiff