battery not detected when managed by PMU (apple powerbook)

[Giuseppe Sacco]

Hello Bastien,

Il giorno lun, 29/06/2020 alle 15.01 +0200, Bastien Nocera ha scritto:
> On Mon, 2020-06-29 at 14:58 +0200, Giuseppe Sacco wrote:
> > Il giorno lun, 29/06/2020 alle 13.06 +0200, Bastien Nocera ha
> > scritto:
> > > On Mon, 2020-06-29 at 12:00 +0100, Richard Hughes wrote:
> > > > On Mon, 29 Jun 2020 at 02:54, Giuseppe Sacco
> > > > <giuseppe at eppesuigoccas.homedns.org> wrote:
> > > > > Browsing UPower source code I noticed that PMU device is not
> > > > > managed at
> > > > > all, at least on the Linux branch.
> > > > 
> > > > If it helps, HAL used to have code to read from PMU devices. I
> > > > don't
> > > > think it got ported all those years ago to DeviceKit-power, the
> > > > old
> > > > name for UPower. I don't think anyone has noticed until now.
> > > 
> > > CONFIG_BATTERY_PMU in the kernel enables a power_supply class
> > > driver
> > > for the PMU. The power portion of CONFIG_ADB_PMU shouldn't be used.
> > 
> > Well, yes, I understand it will be not be used that much since it is
> > an
> > old architecture. If I still try to write the necessary code, is
> > there
> > any way to exclude it when not compiling for powerpc? Do you already
> > selectively compile parts of the code based on the architecture?
> 
> There should be no changes necessary to UPower. Just make sure that a
> "power_supply" class device is present in the kernel for the AC and the
> battery. UPower should be able to handle those.

If I understood what you wrote, the pmu_battery driver registers the
device as of class "power_supply" calling the function power_supply_register() as you may see at line 155 of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/power/pmu_battery.c?h=v3.16.85

Still, upower cannot find it:

$ upower --enumerate
/org/freedesktop/UPower/devices/DisplayDevice

Bye,
Giuseppe