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Created by UC GEE on 7/2/2024 in #middleware-and-os
Trying to interface the BMI088 IMU with an i2c multiplexer
@UC GEE you need to define the channels in your device tree by specifying each device under the appropriate mux channel. Here’s an example: 
i2c1: i2c@40005400 {
    mux {
        compatible = "i2c-mux";
        #address-cells = <1>;
        #size-cells = <0>;
        reg = <0x70>; // I2C multiplexer address

        channel0: chan0 {
            reg = <0>;
            #address-cells = <1>;
            #size-cells = <0>;

            bmi088_acc: accelerometer@18 {
                compatible = "bosch,bmi088-acc";
                reg = <0x18>; // BMI088 accelerometer address
            };
        };

        channel1: chan1 {
            reg = <1>;
            #address-cells = <1>;
            #size-cells = <0>;

            bmi088_gyro: gyroscope@68 {
                compatible = "bosch,bmi088-gyro";
                reg = <0x68>; // BMI088 gyroscope address
            };
        };
    };
};
i2c1: i2c@40005400 {
    mux {
        compatible = "i2c-mux";
        #address-cells = <1>;
        #size-cells = <0>;
        reg = <0x70>; // I2C multiplexer address

        channel0: chan0 {
            reg = <0>;
            #address-cells = <1>;
            #size-cells = <0>;

            bmi088_acc: accelerometer@18 {
                compatible = "bosch,bmi088-acc";
                reg = <0x18>; // BMI088 accelerometer address
            };
        };

        channel1: chan1 {
            reg = <1>;
            #address-cells = <1>;
            #size-cells = <0>;

            bmi088_gyro: gyroscope@68 {
                compatible = "bosch,bmi088-gyro";
                reg = <0x68>; // BMI088 gyroscope address
            };
        };
    };
};
Ensure your mux node in the device tree matches your hardware setup. The addresses 0x18 and 0x68 are examples; you’ll need to use the correct addresses for your BMI088.
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