So I've only found this so far. https://github.com/torvalds/linux/blob/master/drivers/mfd/tps65217.c#L222-#L229
Which I pretty much had already figured out this morning right after I posted. Pretty much, the PMIC sees a condition, that needs attention. It writes some values to registers that relate to the given condition, and then sends an NMI out to the am335x processor. Where the am335x processor immediately picks up that the PMIC needs attention( the whole point of an NMI ), reads the register values out of the PMIC to determine what action needs to be taken. Which in the case of the power button being pressed. the am335x issues a shutdown now -h ( Linux ) Which looking at the code, actually seems like the LKM is actually writing to the PMIC registers to do this ?! Anyway, no idea how a power good condition is being acted on *still*. Meaning, no idea how when a battery is connected, when the external power somehow goes missing. How that particular shutdown is happening, and from where. On Sat, Apr 16, 2016 at 4:32 PM, John Syne <john3...@gmail.com> wrote: > I’m not sure, but best place to look would be > Documentation/power/regulator/charger-management.txt. I believe the PMIC > issues event when AC is removed. > > Regards, > John > > > > > On Apr 16, 2016, at 12:59 PM, William Hermans <yyrk...@gmail.com> wrote: > > Also from what I've read this behavior is different between console and > LXDE images. So if this is true I understand that. I do not want the > behaviors that each of these images provides, but wish to customize my own. > > > On Sat, Apr 16, 2016 at 12:55 PM, William Hermans <yyrk...@gmail.com> > wrote: > >> When a battery is connected to a beaglebone black, how does the software >> know to issue a shutdown when power is no longer coming in ? More >> specifically I'm interested in which file / script performs this action, >> and what mechanism triggers this behavior. >> >> My intentions are to modify / customize what actually happens when power >> to the board is battery only. >> >> >> >> >> >> -- >> 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 beagleboard+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > > -- > 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 beagleboard+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > > > -- > 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 beagleboard+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/F27E94CA-369F-4E5D-8555-EEAD3B034C28%40gmail.com > <https://groups.google.com/d/msgid/beagleboard/F27E94CA-369F-4E5D-8555-EEAD3B034C28%40gmail.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- 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 beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CALHSORoE921k8K-NGxy8SBJaAOn2pda%2BRGc_SEM6pg1naXisaA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
