Vincent Chen

How can I wake up the system from sleep?

Discussion created by Vincent Chen on Apr 2, 2012
Latest reply on Jul 6, 2012 by Vincent Chen

Hi,

Does iMX53 support resume from sleep?

After I execute:  echo mem > state ,  the system seems to suspend to RAM.

Shown as below:

 

root@cpc-105:/# uname -ra
Linux cpc-105 2.6.35.3 #19 PREEMPT Fri Mar 30 18:24:02 CST 2012 armv7l GNU/Linux
root@cpc-105:/# cd /sys/power/
root@cpc-105:/sys/power# cat state
standby mem
root@cpc-105:/sys/power# echo mem > state
[   42.026575] PM: Syncing filesystems ... done.
[   42.042099] Freezing user space processes ... (elapsed 0.01 seconds) done.
[   42.058816] Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
[   42.078833] Suspending console(s) (use no_console_suspend to debug)

 

But how can I wake up the system? Can I use GPIO to wake up the system?

If I execute:   echo standby > state , the system should enter into standby mode.

But it seems no different from suspend to RAM as below:

 

root@cpc-105:/sys/power# cat state
standby mem
root@cpc-105:/sys/power# echo standby > state
[   51.256673] PM: Syncing filesystems ... done.
[   51.272181] Freezing user space processes ... (elapsed 0.01 seconds) done.
[   51.288891] Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
[   51.308906] Suspending console(s) (use no_console_suspend to debug)

Does it mean that standby and sleep are all the same for iMX53?

Thanks for your reply.

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