[U-Boot-Users] Reading from GPIO expander

[Yasothabalan Ramaswamy-TLS,Chennai]

Hi all,

I am using MPC5200B CPU. I am using both the I2C buses of the CPU.

I have connected a PCA9546A 4channel I2C MUX in the one bus.
Through the first channel of the MUX I have connected GPIO expander
PCF8754.

I am able to write into the GPIO expander data register.
Both making the register values high or low is possible by means "imm"
command.

When I try to read the GPIO expander data register by means of "imd"
command I am not getting the value that was written earlier, instead of
that I am getting "00" ( GPIO expander register also getting cleared).

I don't know what may be the issue. 
Please help me how I can read the value that was written previously. 


Regards,
Yasotha Balan R

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