Enabling power management features on 3.8 kernel with device tree


I’ve been trying to get suspend working on a BeagleBone Black with ubuntu kernel version 3.8.13-bone68. As I understand it, in kernel 3.8 the driver binary needs to be loaded manually after boot in the directory /sys/devices/ocp.2/44d00000.wkup_m3/firmware/am335x-pm-firmware.bin/.

My first problem is that /sys/devices/ocp.2/44d00000.wkup_m3 didn’t exist, so I tried adding the following to the device tree file am335x-bone-common.dtsi :

wkup_m3@44d00000 { compatible = “ti,am3353-wkup-m3”; reg = <0x44d00000 0x4000 0x44d80000 0x2000>; ti,hwmods = “wkup_m3”; ti,no-reset-on-init; };

Now /sys/devices/ocp.2/44d00000.wkup_m3/ shows up, but I don’t see any firmware directory in it, just modalias,power,subsystem, and uevent.

I tried adding the line ‘ti,pm-firmware = “am335x-pm-firmware.elf”;’ since I saw it in other examples, but it didn’t help.

Am I missing something simple or am I totally off course here? How do I get the firmware directory to appear? As you can probably tell I’m a bit of a newbie with this stuff!

Thank you

Suspend doesn't work in 3.8..

Currently use "3.14.x-ti" branch for suspend.

It should be working shortly (week or two) in the 4.1.x-ti branch..