Shutdown OS should power down the powerManagement IC as well

Hi,

I have some add on circuitry that uses SYSEN pin of the TPS6950 (the power management IC, I may have the actual name wrong!). Every thing works fine when powering on but, during shutdown, I need to take the SYSEN pin down so that power to my add on circuitry is shut off.

Has any one tried it? How do I shut off the power management IC so that SYSEN is also down? Ideally, I want to do it when the kernel is shutdown (not reboot), probably when “System halted/” message is printed, but, I guess I won’t have any communication modules (i2c etc) available then, so, how would you tell the power management IC to shot down as well?

Appreciate your insights.

–Krishna/.