I am running a Debian GNU/Linux 9 (stretch) release. Linux beaglebone 4.14.49-ti-r54 #1 SMP PREEMPT Fri Jun 15 22:14:13 UTC 2018 armv7l GNU/Linux
The problem is there appears to be no "standby" mode for power. There is freeze, mem and disk. To check this: debian@beaglebone:~$ cat /sys/power/state freeze mem disk sudo echo standby > /sys/power/state Results in Permission denied, any other listed state works. Also using using rtcwake shows similar results: debian@beaglebone:~$ sudo rtcwake -d /dev/rtc0 -m standby -s 10 rtcwake: unrecognized suspend state 'standby' And "MEM' works (but never wakes up): debian@beaglebone:~$ sudo rtcwake -d /dev/rtc0 -m mem -s 60 rtcwake: assuming RTC uses UTC ... rtcwake: wakeup from "mem" using /dev/rtc0 at Wed Sep 4 14:53:45 2019 I can see both and tested the RTC and the GPIO that I use in the wake up sources: $sudo cat /sys/kernel/debug/wakeup_sources In looking a the documentation it appears that the "standby" mode is the only mode that really works. octavo systems app_notes power-management <https://octavosystems.com/app_notes/osd335x-software-control-power-management/> See section 3.1 root@beaglebone:~# cat sys/power/state freeze standby mem disk While the power state names are not the same as modes listed in Table 5, some of them do map to the processors low power modes. The *mem* power state corresponds to *deepsleep0* state of the processor described in Table 5. Similarly, the *standby*power state corresponds to the *standby* state of the processor. More information on these low power modes can be found in the references. The problem is deepsleep0 is not a mode that GPIO works. It appears that "Standby" is the only mode that actually works for GPIO or RTC. I have also tried Debian 9.5 SD IoT, Debian 9.5 SD LXQT, Debian 9.5 IoT Flasher, and Debian 9.4 SD LXQT from Beagle Board latest-images <http://beagleboard.org/latest-images> None of these enabled the "Standby" state in the power modes. Short of going back to a old Debian, any one have a tested solution to fix the missing standby power state? Thanks! :) -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/0da7a142-603f-4d32-b14c-b3919df75818%40googlegroups.com.
