I'm running 2.6.37 kernel on a custom board with DM3730.
I'm having a few issues with suspend-to-memory.
1. Core domain and DSS domain can not switch to retention.
[ 49.842224] PM: suspend of devices complete after 25.451 msecs
[ 49.844421] PM: late suspend of devices complete after 2.197 msecs
[ 52.676818] omap_device: omap_uart.0: new worst case activate latency 0: 30517
[ 52.676910] Powerdomain (core_pwrdm) didn't enter target state 1
[ 52.676940] Powerdomain (dss_pwrdm) didn't enter target state 1
[ 52.676940] Could not enter target state in pm_suspend
2. resume handler in panel driver is not called.
The 2nd problem causes more trouble because panel driver need to initialize the panel after it's powered on.
Now the situation is, as panel's power is controlled by a separate I2C device, and it will power off the panel on suspension and power it back up on resume, but as the initialization routine is not called, the panel can not display anything.
I've read this post but I don't know if those problems are connected.