• Alexander Graf's avatar
    powerpc: Convert power off logic to pm_power_off · 9178ba29
    Alexander Graf authored
    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.
    Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
    [mpe: Squash into one patch and update changelog based on cover letter]
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    9178ba29
linkstation.c 3.85 KB