How is mx6 PMIC_ON_REQ under SW control in WinCE 7?

[sandeepninan]

Hi,

Question: How is mx6 PMIC_ON_REQ under SW control in WinCE?

mx6 PMIC_ON_REQ is hooked up.

We need to have a software control over the PMIC_ON_REQ, to make it go Low/High when it is needed.

The issue is that the reference manual is not clear on how to do this.

We tried to port the linux patch that is provided on Q&A: How is mx6 PMIC_ON_REQ under SW control? but it is not working.

Can anyone please throw some light on the issue. And it would be great if you can provide me a patch to do this.

Thank you in Advance.

Sandeep Ninan

[qiang_li-mpu_se]

Hi Ninan, the PMIC_ON_REQ was controlled by the hardware, no software was needed.

When iMX6 gone to suspend mode, it will pull PMIC_ON_REQ to low, when the PMIC received this signal, it can reduce the power voltage to iMX6 for power saving. And when iMX6 was woke up from suspend mode, it will pull up PMIC_ON_REQ first, when PMIC received this signal, it should recover the voltage to normal mode. After some delay, iMX6 will resume to normal mode.

[tony_l_cai]

Hi,Li

     I find our custom board on MX6DL has the differentials refering to your words. Through my measurement, in suspend(sleep) mode, power off state, normal mode, the Pin PMIC_ON_REQ is always logical level high. Only in No power state(adapt was plugged out),the Pin PMIC_ON_REQ has no voltage, why?

[qiang_li-mpu_se]

Hi Tony, if the CPU hasn't run to suspend mode successfully, this will happen.

[tony_l_cai]

Hi Li，

     I want to enter into POWER OFF state not suspend mode(sleep mode,power down mode), and when I enter into POWER OFF state, PMIC_ON_REQ is still 3.3 V, why?

3Q~~

[qiang_li-mpu_se]

If some drivers blocked the kernel suspend, the CPU will not run into suspend state, then PMIC_ON_REQ will keep high.

So you should check why the kernel suspend hasn't run successfully.

[qiang_li-mpu_se]

After CPU goto suspend, your hardware can shut down the power for the POWER OFF state, it depends on your hardware design.

[sandeepninan]

Hi Li,

Thank you for your reply,

Actually my doubt is that, Is it possible to pull PMIC_ON_REQ to low by software? I am working in WEC7, could you please help me in this.

[CarlosCasillas]

The signal from the PMIC_ON_REQ can not be handle by software. Since it is not implemented in WEC7

[sandeepninan]

Thank you Carlos,  I am trying to implement it on WEC7. Is it possible to pull the PMIC_ON_REQ to low by writing the value 0X60 to the SVNS_LPCR register? Like it was mentioned on the Linux patch given in: Q&A: How is mx6 PMIC_ON_REQ under SW control?.

[qiang_li-mpu_se]

Hi Ninan, I think writen 0x60 to LPCR register can also work in WinCE7 BSP.