diff options
Diffstat (limited to 'drivers/iio/imu/bmi323/bmi323_i2c.c')
| -rw-r--r-- | drivers/iio/imu/bmi323/bmi323_i2c.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/iio/imu/bmi323/bmi323_i2c.c b/drivers/iio/imu/bmi323/bmi323_i2c.c new file mode 100644 index 000000000000..20a8001b9956 --- /dev/null +++ b/drivers/iio/imu/bmi323/bmi323_i2c.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * I2C driver for Bosch BMI323 6-Axis IMU. + * + * Copyright (C) 2023, Jagath Jog J <jagathjog1996@gmail.com> + */ + +#include <linux/i2c.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "bmi323.h" + +struct bmi323_i2c_priv { + struct i2c_client *i2c; + u8 i2c_rx_buffer[BMI323_FIFO_LENGTH_IN_BYTES + BMI323_I2C_DUMMY]; +}; + +/* + * From BMI323 datasheet section 4: Notes on the Serial Interface Support. + * Each I2C register read operation requires to read two dummy bytes before + * the actual payload. + */ +static int bmi323_regmap_i2c_read(void *context, const void *reg_buf, + size_t reg_size, void *val_buf, + size_t val_size) +{ + struct bmi323_i2c_priv *priv = context; + struct i2c_msg msgs[2]; + int ret; + + msgs[0].addr = priv->i2c->addr; + msgs[0].flags = priv->i2c->flags; + msgs[0].len = reg_size; + msgs[0].buf = (u8 *)reg_buf; + + msgs[1].addr = priv->i2c->addr; + msgs[1].len = val_size + BMI323_I2C_DUMMY; + msgs[1].buf = priv->i2c_rx_buffer; + msgs[1].flags = priv->i2c->flags | I2C_M_RD; + + ret = i2c_transfer(priv->i2c->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) + return -EIO; + + memcpy(val_buf, priv->i2c_rx_buffer + BMI323_I2C_DUMMY, val_size); + + return 0; +} + +static int bmi323_regmap_i2c_write(void *context, const void *data, + size_t count) +{ + struct bmi323_i2c_priv *priv = context; + u8 reg; + + reg = *(u8 *)data; + return i2c_smbus_write_i2c_block_data(priv->i2c, reg, + count - sizeof(u8), + data + sizeof(u8)); +} + +static struct regmap_bus bmi323_regmap_bus = { + .read = bmi323_regmap_i2c_read, + .write = bmi323_regmap_i2c_write, +}; + +static const struct regmap_config bmi323_i2c_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .max_register = BMI323_CFG_RES_REG, + .val_format_endian = REGMAP_ENDIAN_LITTLE, +}; + +static int bmi323_i2c_probe(struct i2c_client *i2c) +{ + struct device *dev = &i2c->dev; + struct bmi323_i2c_priv *priv; + struct regmap *regmap; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->i2c = i2c; + regmap = devm_regmap_init(dev, &bmi323_regmap_bus, priv, + &bmi323_i2c_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "Failed to initialize I2C Regmap\n"); + + return bmi323_core_probe(dev); +} + +static const struct i2c_device_id bmi323_i2c_ids[] = { + { "bmi323" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, bmi323_i2c_ids); + +static const struct of_device_id bmi323_of_i2c_match[] = { + { .compatible = "bosch,bmi323" }, + { } +}; +MODULE_DEVICE_TABLE(of, bmi323_of_i2c_match); + +static struct i2c_driver bmi323_i2c_driver = { + .driver = { + .name = "bmi323", + .of_match_table = bmi323_of_i2c_match, + }, + .probe = bmi323_i2c_probe, + .id_table = bmi323_i2c_ids, +}; +module_i2c_driver(bmi323_i2c_driver); + +MODULE_DESCRIPTION("Bosch BMI323 IMU driver"); +MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(IIO_BMI323); |