iMX28 wake up from suspend-to-idle

[damienlagneux]

Hi,

I'm having trouble waking up imx28 from suspend-to-idle using GPIO interrupt.

It turns out that when the system is in suspend-to-ram sleep state, it can be woken using a GPIO. The problem is only with suspend-to-idle state.

Any idea where the problem comes from?

Thanks for the help,

Damien

[lategoodbye]

Hi Damien,

i've sent a patch to fix this issue for the mainline kernel:

http://marc.info/?l=linux-arm-kernel&m=148286401809773&w=2

[igorpadykov]

Hi Damien

FSL i.MX28 BSP does not use "suspend-to-idle" low power mode,

implemented modes are described in attached Linux Manual Chapter 8

and AN4199 sect.2.6 Low-power modes.

In general power management in Linux may have many modes but not all of them

can be implemented in BSP.

Best regards

igor

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[damienlagneux]

Hi Igor,

Thank you for your answer.

The thing is, suspend-to-idle state is "pure software" and "always supported" as said in https://www.kernel.org/doc/Documentation/power/states.txt. Moreover, the system can be woken up from suspend-to-idle state using serial port for example.

That's why I don't understand why it can't be woken up using GPIO.

Best regards,

Damien

[igorpadykov]

Hi Damien

seems one can post this to kernel.org mailing list

Best regards

igor

[damienlagneux]

I'm on it, thanks Igor.

Regards,

Damien