Hi Alex, On Wed, Oct 1, 2014 at 3:27 PM, Alexander Graf <ag...@suse.de> wrote: > The generic Linux framework to power off the machine is a function pointer > called pm_power_off. The trick about this pointer is that device drivers can > potentially implement it rather than board files. > > Today on PowerPC we set pm_power_off to invoke our generic full machine power > off logic which then calls ppc_md.power_off to invoke machine specific power > off. > > However, when we want to add a power off GPIO via the "gpio-poweroff" driver, > this card house falls apart. That driver only registers itself if pm_power_off > is NULL to ensure it doesn't override board specific logic. However, since we > always set pm_power_off to the generic power off logic (which will just not > power off the machine if no ppc_md.power_off call is implemented), we can't > implement power off via the generic GPIO power off driver. > > To fix this up, let's get rid of the ppc_md.power_off logic and just always > use > pm_power_off as was intended. Then individual drivers such as the GPIO power > off > driver can implement power off logic via that function pointer. > > With this patch set applied and a few patches on top of QEMU that implement a > power off GPIO on the virt e500 machine, I can successfully turn off my > virtual > machine after halt.
This is touching the same area as last night's "[RFC PATCH 00/16] kernel: Add support for poweroff handler call chain" https://lkml.org/lkml/2014/9/30/575 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
