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    SubjectRe: pci_disable_device() vs. arch
    >huh?  pci_enable_device calls pci_set_power_state.  sungem calls
    >pcibios_enable_device shouldn't have to worry about power stuff. If it
    >does, you need a pcibios_set_power_state, called from
    >pci_set_power_state, instead.

    Right, having a hook in pci_set_power_state() handles it all. Now,
    there need to be some thinking about how to actually implement it
    (when to call pcibios_set_power_state inside pci_set_power_state
    and what result should it returns).

    I see several options:

    - Use it when the device has no PM capabilities
    - Call it first, and depending on the result code, do the normal
    PM or not, or eventually just fail.
    - Call it last/first depending if entering a low power state or

    In my case, the device don't have PM caps, so I don't really care,
    and it's the same for the other devices I have in mind that would
    need it.

    I still like the idea of implementing this as a function pointer
    inside the pci_bus. In fact, the current implementation could be
    done by filling this pointer with a default value, thus allowing
    the arch to do any variation it may like by overriding this

    I keep having embedded in mind, where we have all sort of weird
    designs (usually to save a few wires on a PLD) and flexibility is
    fine when it doesn't add bloat. In this case, I beleive having
    this notion of "pci_bus ops" for PM makes sense and is not bloat.

    >Via is an exception

    Yes, unless it's cascaded on a master interrupt controller. But
    I agree the hard coding wasn't good, PPC is just so many different
    boxes, they don't all have a nice device-tree or useable BIOS
    residual datas :(

    >Ok, agreed. There are always gonna be special case bridges, including
    >(for my interest) multi-port NICs whose interfaces are presented as PCI
    >devices downstream from a PCI-PCI bridge. Controlling power for these
    >nics is sometimes done by messing around with the PM bits on the bridge,
    >not on the downstream devices.

    Ah, nice you see you agree ;)


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