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I2C expander PCA9539 showing on bus -1

Question asked by Arun kumar on Jun 13, 2018

I am trying to bring up PCA9546(switch) and PCA9539(I2C expander) in uboot, so that i can bring up some peripherals connected via I2C switch(PCA9546)-->I2C expander(PCA9539).

I have added dts entry like this,

&i2c1 {
.
.
.
   i2cswitch@70 {
      compatible = "nxp,pca9546";
      #address-cells = <1>;
      #size-cells = <0>;
      reg = <0x70>;

   

      i2c@1 {
         #address-cells = <1>;
         #size-cells = <0>;
         reg = <1>;

            pca9539@74 {
                  compatible = "nxp,pca9539";
                  reg = <0x74>;
                  gpio-controller;
                  #gpio-cells = <2>;
            };

      };
   };

};


I2C expander(PCA9539) is connected to channel 1 of switch(PCA9546) but in uboot i2c logs, I2C expander is showing on bus -1.

u-boot logs,

=> i2c bus
Bus 0: i2c@48070000 (active 0)
58: tps659038@58, offset len 1, flags 0
20: gpio@20, offset len 1, flags 0
21: gpio@21, offset len 0, flags 0
70: i2cswitch@70, offset len 1, flags 0

Bus -1: i2c@1

74: pca9539@74, offset len 1, flags 0

Any help will be highly appreciated.

Thanks,

Arun

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