# SMI230-Linux-Driver

**Repository Path**: rudyzh4ng/SMI230-Linux-Driver

## Basic Information

- **Project Name**: SMI230-Linux-Driver
- **Description**: SMI230 linux driver
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: linux-5.4
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 1
- **Forks**: 0
- **Created**: 2021-03-22
- **Last Updated**: 2022-09-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# SMI230-Sensor-API and Sensor Driver

## Table of Contents
 - [Introduction](#Intro)
 - [License](#License)
 - [Sensor interfaces](#interfaces)
 - [Architecture](#Architecture)
 - [Operation examples](#examples)

## Introduction <a name=Intro></a>

SMI230 is a system-in-package inertial measurement unit which offers accurate acceleration and angular rate measurements.
Due to system-in-package approach of SMI230 (two sensors in single package), the gyroscope and acceleration data is acquired in a non-synchronized manner. 
However, synchronization between accelerometer and gyroscope can be achieved:
The software modules in this repository are provided as reference for SMI230 users and shall demonstrate exemplarily the usage of the following features
- data synchronization.
- data collection from FIFO.

_Note: The sensor driver utilizes sensor api, which is following BMI08x sensor api available on [github](https://github.com/BoschSensortec/BMI08x-Sensor-API/releases/tag/bmi08x_v1.4.4)._

_Note: The data synchronization feature utilizes sensor configuration, which is following BMI08x sensor configuration available on [github](https://github.com/BoschSensortec/BMI08x-Sensor-API/releases/tag/bmi08x_v1.2.0)._

## License <a name=License></a>
See [LICENSE](drivers/input/sensors/smi230/LICENSE.md) file

## Sensor interfaces <a name=interfaces></a>
* I2C
* SPI

## Architecture <a name=Architecture></a>
```
                  User space
-------------------------------------------------------
                 |          |
               sysfs       dev
                 \          /
               input-subsystem
	             |
sensor_API <-- smi230_driver --> smi230_SPI/I2C_driver
                                           |
                                      SPI/I2C_bus
                                           |
-------------------------------------------------------
                  Hardware
```
## Operation examples <a name=examples></a>
1. Userspace
The driver exposes a device file node under /dev/input/event*, which can be read as a normal Linux file. Tools like evtest can also be used for read data out. Eg.:
```
sudo evtest /dev/input/event0
```
The data will be displayed on the console with timestamp.

2. Sysfs
The driver also exposes a set of sysfs nodes under /sys/devices/virtual/input/input*, where users can get information about the sensor and also control the sensor. Eg.:
```
# read the acc power config
cat /sys/devices/virtual/input/input0/acc_pw_cfg

# set the acc power config active, this command is needed if acc needs to be fully fuctional.
echo 0 > /sys/devices/virtual/input/input0/acc_pw_cfg

# set the acc power config suspend
echo 3 > /sys/devices/virtual/input/input0/acc_pw_cfg

# read the gyro power config
cat /sys/devices/virtual/input/input0/gyro_pw_cfg

# set the gyro power config active, this command is needed if gyro needs to be fully fuctional.
echo 0 > /sys/devices/virtual/input/input0/gyro_pw_cfg

# set the gyro power config suspend
echo 3 > /sys/devices/virtual/input/input0/gyro_pw_cfg

# read the chip id
cat /sys/devices/virtual/input/input0/chip_id

# read the synced acc data 
cat /sys/devices/virtual/input/input0/data_sync

# read the asynced acc data 
cat /sys/devices/virtual/input/input0/acc_value

# read the gyro data 
cat /sys/devices/virtual/input/input0/gyro_value

```