Fixing BMI088 IMU connected via I2C

[slgrobotics]

Solved Problem

In my testing of Bosch Sensortec BMI088 IMU data logged to an ulg file had strange spikes and was not good for EKF either.

Fixes #23111

Solution

It looks like there's a problem reading FIFO - at least for I2C connected devices.

Reading data directly from device registers (for both accelerometer and gyroscope) - using NormalRead() functions seem to solve this issue.

Test coverage

I use a Raspberry Pi 4 and SeeedStudio BMI088 breakboard to test this code, as this is what I have on my two rovers.

More testing on Bitcraze CrazyFlie 2.1 hardware should be done, as this is the only PX4-supported platform that uses I2C for this IMU. All others connect BMI088 via SPI and therefore use different driver.

make bitcraze_crazyflie21

Notes:

1. I believe that the code for SPI-connected devices has an error when incoming values are compared with INT16_MIN. If any of X, Y or Z values are equal to INT16_MIN - whole sample must be discarded.
   This is described in BMI088 connected via I2C does not work right[Bug]  #23111

2. There's a lot of unused FIFO-related code in bmi088_i2c driver. It can be removed as we progress with this PR.

[slgrobotics]

@mrpollo - here is a log file - rover makes a couple turns in manual mode. I have MPU9250/SPI as #01 and BMI088/I2C as #00 - and their data seems close enough:

https://review.px4.io/plot_app?log=e4e0e80c-3d80-490c-ae9b-821a76a0f3a0

[slgrobotics]

Related PRs and Issues:

#15361

#17082

#22684

[slgrobotics]

Just FYI: I have a version of bmi088_i2c driver that works for my rovers well. It is cleaned off all the FIFO code and I revamped some register settings for clarity. I use low frequencies for low pass filters too, so that all vibrations are filtered out. I also added additional EMA filter to smooth the data even further in controlled manner.

https://github.com/slgrobotics/PX4-Autopilot/tree/main/src/drivers/imu/bosch/bmi088_i2c