Sorry for resending this thread. Last thread is forgot to CC Greg Kroah-Hartman. The [1/2] fix this situation: we set no_console_supend and console=ttyS0 to bootargs, then bootup the kernel, the boot logs will print out from ttyS0. When we execute echo mem > /sys/power/state, the system will suspend, we press a key(or other wakeup trigger) to resume the system, but the ttyS0 can't work anymore. The [2/2] fix this situation: we set console=ttyS0 to bootargs, then bootup the kernel, the boot logs will print out from ttyS0, this time we set ttyS1 as tty and login for shell. When we execute echo mem > /sys/power/state, the system will suspend, we press a key(or other wakeup trigger) to resume the system, but the ttyS0 can't work anymore. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html