[PATCH v4 2/2] iio: imu: Add i2c driver for bmi270 imu
From: Alex Lanzano
Date: Thu Sep 12 2024 - 17:08:53 EST
Add initial i2c support for the Bosch BMI270 6-axis IMU.
Provides raw read access to acceleration and angle velocity measurements
via iio channels. Device configuration requires firmware provided by
Bosch and is requested and load from userspace.
Signed-off-by: Alex Lanzano <lanzano.alex@xxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/iio/imu/Kconfig | 1 +
drivers/iio/imu/Makefile | 1 +
drivers/iio/imu/bmi270/Kconfig | 21 +++
drivers/iio/imu/bmi270/Makefile | 6 +
drivers/iio/imu/bmi270/bmi270.h | 62 +++++++
drivers/iio/imu/bmi270/bmi270_core.c | 258 +++++++++++++++++++++++++++
drivers/iio/imu/bmi270/bmi270_i2c.c | 48 +++++
8 files changed, 404 insertions(+)
create mode 100644 drivers/iio/imu/bmi270/Kconfig
create mode 100644 drivers/iio/imu/bmi270/Makefile
create mode 100644 drivers/iio/imu/bmi270/bmi270.h
create mode 100644 drivers/iio/imu/bmi270/bmi270_core.c
create mode 100644 drivers/iio/imu/bmi270/bmi270_i2c.c
diff --git a/MAINTAINERS b/MAINTAINERS
index dd4588838d90..faf109ae60eb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3928,6 +3928,13 @@ S: Maintained
F: Documentation/devicetree/bindings/iio/accel/bosch,bma400.yaml
F: drivers/iio/accel/bma400*
+BOSCH SENSORTEC BMI270 IMU IIO DRIVER
+M: Alex Lanzano <lanzano.alex@xxxxxxxxx>
+L: linux-iio@xxxxxxxxxxxxxxx
+S: Maintained
+F: Documentation/devicetree/bindings/iio/imu/bosch,bmi270.yaml
+F: drivers/iio/imu/bmi270/
+
BOSCH SENSORTEC BMI323 IMU IIO DRIVER
M: Jagath Jog J <jagathjog1996@xxxxxxxxx>
L: linux-iio@xxxxxxxxxxxxxxx
diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
index 782fb80e44c2..489dd898830b 100644
--- a/drivers/iio/imu/Kconfig
+++ b/drivers/iio/imu/Kconfig
@@ -53,6 +53,7 @@ config ADIS16480
ADIS16485, ADIS16488 inertial sensors.
source "drivers/iio/imu/bmi160/Kconfig"
+source "drivers/iio/imu/bmi270/Kconfig"
source "drivers/iio/imu/bmi323/Kconfig"
source "drivers/iio/imu/bno055/Kconfig"
diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
index 7e2d7d5c3b7b..79f83ea6f644 100644
--- a/drivers/iio/imu/Makefile
+++ b/drivers/iio/imu/Makefile
@@ -15,6 +15,7 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
obj-y += bmi160/
+obj-y += bmi270/
obj-y += bmi323/
obj-y += bno055/
diff --git a/drivers/iio/imu/bmi270/Kconfig b/drivers/iio/imu/bmi270/Kconfig
new file mode 100644
index 000000000000..3f7b4ac30f00
--- /dev/null
+++ b/drivers/iio/imu/bmi270/Kconfig
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# BMI270 IMU driver
+#
+
+config BMI270
+ tristate
+ select IIO_BUFFER
+
+config BMI270_I2C
+ tristate "Bosch BMI270 I2C driver"
+ depends on I2C
+ select BMI270
+ select REGMAP_I2C
+ help
+ Enable support for the Bosch BMI270 6-Axis IMU connected to I2C
+ interface.
+
+ This driver can also be built as a module. If so, the module will be
+ called bmi270_i2c.
+
diff --git a/drivers/iio/imu/bmi270/Makefile b/drivers/iio/imu/bmi270/Makefile
new file mode 100644
index 000000000000..ab4acaaee6d2
--- /dev/null
+++ b/drivers/iio/imu/bmi270/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for Bosch BMI270 IMU
+#
+obj-$(CONFIG_BMI270) += bmi270_core.o
+obj-$(CONFIG_BMI270_I2C) += bmi270_i2c.o
diff --git a/drivers/iio/imu/bmi270/bmi270.h b/drivers/iio/imu/bmi270/bmi270.h
new file mode 100644
index 000000000000..4af4098d8e82
--- /dev/null
+++ b/drivers/iio/imu/bmi270/bmi270.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+
+#ifndef BMI270_H_
+#define BMI270_H_
+
+#include <linux/iio/iio.h>
+
+#define BMI270_CHIP_ID_REG 0x00
+#define BMI270_CHIP_ID_VAL 0x24
+#define BMI270_CHIP_ID_MSK GENMASK(7, 0)
+
+#define BMI270_ACCEL_X_REG 0x0c
+#define BMI270_ANG_VEL_X_REG 0x12
+
+#define BMI270_INTERNAL_STATUS_REG 0x21
+#define BMI270_INTERNAL_STATUS_MSG_MSK GENMASK(3, 0)
+#define BMI270_INTERNAL_STATUS_MSG_INIT_OK 0x01
+
+#define BMI270_INTERNAL_STATUS_AXES_REMAP_ERR_MSK BIT(5)
+#define BMI270_INTERNAL_STATUS_ODR_50HZ_ERR_MSK BIT(6)
+
+#define BMI270_ACC_CONF_REG 0x40
+#define BMI270_ACC_CONF_ODR_MSK GENMASK(3, 0)
+#define BMI270_ACC_CONF_ODR_100HZ 0x08
+#define BMI270_ACC_CONF_BWP_MSK GENMASK(6, 4)
+#define BMI270_ACC_CONF_BWP_NORMAL_MODE 0x02
+#define BMI270_ACC_CONF_FILTER_PERF_MSK BIT(7)
+
+#define BMI270_GYR_CONF_REG 0x42
+#define BMI270_GYR_CONF_ODR_MSK GENMASK(3, 0)
+#define BMI270_GYR_CONF_ODR_200HZ 0x09
+#define BMI270_GYR_CONF_BWP_MSK GENMASK(5, 4)
+#define BMI270_GYR_CONF_BWP_NORMAL_MODE 0x02
+#define BMI270_GYR_CONF_NOISE_PERF_MSK BIT(6)
+#define BMI270_GYR_CONF_FILTER_PERF_MSK BIT(7)
+
+#define BMI270_INIT_CTRL_REG 0x59
+#define BMI270_INIT_CTRL_LOAD_DONE_MSK BIT(0)
+
+#define BMI270_INIT_DATA_REG 0x5e
+
+#define BMI270_PWR_CONF_REG 0x7c
+#define BMI270_PWR_CONF_ADV_PWR_SAVE_MSK BIT(0)
+#define BMI270_PWR_CONF_FIFO_WKUP_MSK BIT(1)
+#define BMI270_PWR_CONF_FUP_EN_MSK BIT(2)
+
+#define BMI270_PWR_CTRL_REG 0x7d
+#define BMI270_PWR_CTRL_AUX_EN_MSK BIT(0)
+#define BMI270_PWR_CTRL_GYR_EN_MSK BIT(1)
+#define BMI270_PWR_CTRL_ACCEL_EN_MSK BIT(2)
+#define BMI270_PWR_CTRL_TEMP_EN_MSK BIT(3)
+
+struct bmi270_data {
+ struct device *dev;
+ struct regmap *regmap;
+};
+
+extern const struct regmap_config bmi270_regmap_config;
+
+int bmi270_core_probe(struct device *dev, struct regmap *regmap);
+
+#endif /* BMI270_H_ */
diff --git a/drivers/iio/imu/bmi270/bmi270_core.c b/drivers/iio/imu/bmi270/bmi270_core.c
new file mode 100644
index 000000000000..319e5601d9e7
--- /dev/null
+++ b/drivers/iio/imu/bmi270/bmi270_core.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/bitfield.h>
+
+#include "bmi270.h"
+
+#define BMI270_INIT_DATA_FILE "bmi270-init-data.fw"
+
+enum bmi270_scan {
+ BMI270_SCAN_ACCEL_X,
+ BMI270_SCAN_ACCEL_Y,
+ BMI270_SCAN_ACCEL_Z,
+ BMI270_SCAN_GYRO_X,
+ BMI270_SCAN_GYRO_Y,
+ BMI270_SCAN_GYRO_Z,
+};
+
+const struct regmap_config bmi270_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+EXPORT_SYMBOL_NS_GPL(bmi270_regmap_config, IIO_BMI270);
+
+static int bmi270_get_data(struct bmi270_data *bmi270_device,
+ int chan_type, int axis, int *val)
+{
+ __le16 sample;
+ int reg;
+ int ret;
+
+ switch (chan_type) {
+ case IIO_ACCEL:
+ reg = BMI270_ACCEL_X_REG + (axis - IIO_MOD_X) * sizeof(sample);
+ break;
+ case IIO_ANGL_VEL:
+ reg = BMI270_ANG_VEL_X_REG + (axis - IIO_MOD_X) * sizeof(sample);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = regmap_bulk_read(bmi270_device->regmap, reg, &sample, sizeof(sample));
+ if (ret)
+ return ret;
+
+ *val = sign_extend32(le16_to_cpu(sample), 15);
+
+ return 0;
+}
+
+static int bmi270_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ struct bmi270_data *bmi270_device = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = bmi270_get_data(bmi270_device, chan->type, chan->channel2, val);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info bmi270_info = {
+ .read_raw = bmi270_read_raw,
+};
+
+#define BMI270_ACCEL_CHANNEL(_axis) { \
+ .type = IIO_ACCEL, \
+ .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_FREQUENCY), \
+}
+
+#define BMI270_ANG_VEL_CHANNEL(_axis) { \
+ .type = IIO_ANGL_VEL, \
+ .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_FREQUENCY), \
+}
+
+static const struct iio_chan_spec bmi270_channels[] = {
+ BMI270_ACCEL_CHANNEL(X),
+ BMI270_ACCEL_CHANNEL(Y),
+ BMI270_ACCEL_CHANNEL(Z),
+ BMI270_ANG_VEL_CHANNEL(X),
+ BMI270_ANG_VEL_CHANNEL(Y),
+ BMI270_ANG_VEL_CHANNEL(Z)
+};
+
+static int bmi270_validate_chip_id(struct bmi270_data *bmi270_device)
+{
+ int chip_id;
+ int ret;
+ struct device *dev = bmi270_device->dev;
+ struct regmap *regmap = bmi270_device->regmap;
+
+ ret = regmap_read(regmap, BMI270_CHIP_ID_REG, &chip_id);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to read chip id");
+
+ if (chip_id != BMI270_CHIP_ID_VAL)
+ return dev_err_probe(dev, -ENODEV, "Invalid chip id 0x%x", chip_id);
+
+ return 0;
+}
+
+static int bmi270_write_calibration_data(struct bmi270_data *bmi270_device)
+{
+ int ret;
+ int status = 0;
+ const struct firmware *init_data;
+ struct device *dev = bmi270_device->dev;
+ struct regmap *regmap = bmi270_device->regmap;
+
+ ret = regmap_clear_bits(regmap, BMI270_PWR_CONF_REG, BMI270_PWR_CONF_ADV_PWR_SAVE_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to write power configuration");
+
+ /* After disabling advanced power save, all registers are accessible after a 450us delay
+ * This delay is specified in table A of the datasheet.
+ */
+ usleep_range(450, 1000);
+
+ ret = regmap_clear_bits(regmap, BMI270_INIT_CTRL_REG, BMI270_INIT_CTRL_LOAD_DONE_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to prepare device to load init data");
+
+ ret = request_firmware(&init_data, BMI270_INIT_DATA_FILE, dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to load init data file");
+
+ ret = regmap_bulk_write(regmap, BMI270_INIT_DATA_REG,
+ init_data->data, init_data->size);
+ release_firmware(init_data);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to write init data");
+
+ ret = regmap_set_bits(regmap, BMI270_INIT_CTRL_REG, BMI270_INIT_CTRL_LOAD_DONE_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to stop device initialization");
+
+ /* Wait at least 140ms for the device to complete configuration.
+ * This delay is specified in table C of the datasheet.
+ */
+ usleep_range(140000, 160000);
+
+ ret = regmap_read(regmap, BMI270_INTERNAL_STATUS_REG, &status);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to read internal status");
+
+ if (status != BMI270_INTERNAL_STATUS_MSG_INIT_OK)
+ return dev_err_probe(dev, -ENODEV, "Device failed to initialize");
+
+ return 0;
+}
+
+static int bmi270_configure_imu(struct bmi270_data *bmi270_device)
+{
+ int ret;
+ struct device *dev = bmi270_device->dev;
+ struct regmap *regmap = bmi270_device->regmap;
+
+ ret = regmap_set_bits(regmap, BMI270_PWR_CTRL_REG,
+ BMI270_PWR_CTRL_AUX_EN_MSK |
+ BMI270_PWR_CTRL_GYR_EN_MSK |
+ BMI270_PWR_CTRL_ACCEL_EN_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to enable accelerometer and gyroscope");
+
+ ret = regmap_set_bits(regmap, BMI270_ACC_CONF_REG,
+ FIELD_PREP(BMI270_ACC_CONF_ODR_MSK,
+ BMI270_ACC_CONF_ODR_100HZ) |
+ FIELD_PREP(BMI270_ACC_CONF_BWP_MSK,
+ BMI270_ACC_CONF_BWP_NORMAL_MODE) |
+ BMI270_PWR_CONF_ADV_PWR_SAVE_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to configure accelerometer");
+
+ ret = regmap_set_bits(regmap, BMI270_GYR_CONF_REG,
+ FIELD_PREP(BMI270_GYR_CONF_ODR_MSK,
+ BMI270_GYR_CONF_ODR_200HZ) |
+ FIELD_PREP(BMI270_GYR_CONF_BWP_MSK,
+ BMI270_GYR_CONF_BWP_NORMAL_MODE) |
+ BMI270_PWR_CONF_ADV_PWR_SAVE_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to configure gyroscope");
+
+ /* Enable FIFO_WKUP, Disable ADV_PWR_SAVE and FUP_EN */
+ ret = regmap_write(regmap, BMI270_PWR_CONF_REG,
+ BMI270_PWR_CONF_FIFO_WKUP_MSK);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to set power configuration");
+
+ return 0;
+}
+
+static int bmi270_chip_init(struct bmi270_data *bmi270_device)
+{
+ int ret;
+
+ ret = bmi270_validate_chip_id(bmi270_device);
+ if (ret)
+ return ret;
+
+ ret = bmi270_write_calibration_data(bmi270_device);
+ if (ret)
+ return ret;
+
+ return bmi270_configure_imu(bmi270_device);
+}
+
+int bmi270_core_probe(struct device *dev, struct regmap *regmap)
+{
+ int ret;
+ struct bmi270_data *bmi270_device;
+ struct iio_dev *indio_dev;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(struct bmi270_data *));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ bmi270_device = iio_priv(indio_dev);
+ bmi270_device->dev = dev;
+ bmi270_device->regmap = regmap;
+
+ ret = bmi270_chip_init(bmi270_device);
+ if (ret)
+ return ret;
+
+ indio_dev->channels = bmi270_channels;
+ indio_dev->num_channels = ARRAY_SIZE(bmi270_channels);
+ indio_dev->name = "bmi270";
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &bmi270_info;
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+EXPORT_SYMBOL_NS_GPL(bmi270_core_probe, IIO_BMI270);
+
+MODULE_AUTHOR("Alex Lanzano");
+MODULE_DESCRIPTION("BMI270 driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/imu/bmi270/bmi270_i2c.c b/drivers/iio/imu/bmi270/bmi270_i2c.c
new file mode 100644
index 000000000000..f70dee2d8a64
--- /dev/null
+++ b/drivers/iio/imu/bmi270/bmi270_i2c.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/regmap.h>
+
+#include "bmi270.h"
+
+static int bmi270_i2c_probe(struct i2c_client *client)
+{
+ struct regmap *regmap;
+ struct device *dev = &client->dev;
+
+ regmap = devm_regmap_init_i2c(client, &bmi270_regmap_config);
+ if (IS_ERR(regmap))
+ return dev_err_probe(dev, PTR_ERR(regmap),
+ "Failed to init i2c regmap");
+
+ return bmi270_core_probe(dev, regmap);
+}
+
+static const struct i2c_device_id bmi270_i2c_id[] = {
+ { "bmi270", 0 },
+ { }
+};
+
+static const struct of_device_id bmi270_of_match[] = {
+ { .compatible = "bosch,bmi270" },
+ { }
+};
+
+static struct i2c_driver bmi270_i2c_driver = {
+ .driver = {
+ .name = "bmi270_i2c",
+ .of_match_table = bmi270_of_match,
+ },
+ .probe = bmi270_i2c_probe,
+ .id_table = bmi270_i2c_id,
+};
+module_i2c_driver(bmi270_i2c_driver);
+
+MODULE_AUTHOR("Alex Lanzano");
+MODULE_DESCRIPTION("BMI270 driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_BMI270);
--
2.46.0