iio: imu: Add i2c driver for bmi270 imu
authorAlex Lanzano <lanzano.alex@gmail.com>
Thu, 12 Sep 2024 21:07:19 +0000 (17:07 -0400)
committerJonathan Cameron <Jonathan.Cameron@huawei.com>
Mon, 30 Sep 2024 08:21:03 +0000 (09:21 +0100)
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@gmail.com>
Link: https://patch.msgid.link/20240912210749.3080157-3-lanzano.alex@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
MAINTAINERS
drivers/iio/imu/Kconfig
drivers/iio/imu/Makefile
drivers/iio/imu/bmi270/Kconfig [new file with mode: 0644]
drivers/iio/imu/bmi270/Makefile [new file with mode: 0644]
drivers/iio/imu/bmi270/bmi270.h [new file with mode: 0644]
drivers/iio/imu/bmi270/bmi270_core.c [new file with mode: 0644]
drivers/iio/imu/bmi270/bmi270_i2c.c [new file with mode: 0644]

index c27f3190737f8b85779bde5489639c8b899f4fd8..4d123e4fd3e79c8048dcdaa16fc0f482a0107f91 100644 (file)
@@ -4035,6 +4035,13 @@ 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@gmail.com>
+L:     linux-iio@vger.kernel.org
+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@gmail.com>
 L:     linux-iio@vger.kernel.org
index 782fb80e44c234911d07a56a1cad11eaed029303..489dd898830bfc0d8bf7cc4098921698a50a6585 100644 (file)
@@ -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"
 
index 7e2d7d5c3b7bc7e76dfd00ff8437cb3c640e8a54..79f83ea6f6443f049eece8f84f85ad2e861f28af 100644 (file)
@@ -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 (file)
index 0000000..a8db441
--- /dev/null
@@ -0,0 +1,20 @@
+# 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 (file)
index 0000000..ab4acaa
--- /dev/null
@@ -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 (file)
index 0000000..608b29e
--- /dev/null
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+
+#ifndef BMI270_H_
+#define BMI270_H_
+
+#include <linux/regmap.h>
+
+struct device;
+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 (file)
index 0000000..8e45343
--- /dev/null
@@ -0,0 +1,313 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+#include <linux/bitfield.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include <linux/iio/iio.h>
+
+#include "bmi270.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)
+
+#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) * 2;
+               break;
+       case IIO_ANGL_VEL:
+               reg = BMI270_ANG_VEL_X_REG + (axis - IIO_MOD_X) * 2;
+               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)
+               dev_info(dev, "Unknown 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(*bmi270_device));
+       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 (file)
index 0000000..f70dee2
--- /dev/null
@@ -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);