Grant Likely <grant.likely@xxxxxxxxxxxx> writes: > On Tue, Aug 3, 2010 at 10:16 AM, Kevin Hilman > <khilman@xxxxxxxxxxxxxxxxxxx> wrote: >> Magnus Damm <magnus.damm@xxxxxxxxx> writes: >> >>> On Sun, Jul 25, 2010 at 5:24 AM, Grant Likely <grant.likely@xxxxxxxxxxxx> wrote: >>>> "Magnus Damm" <magnus.damm@xxxxxxxxx> wrote: >>>>>On Tue, Oct 27, 2009 at 8:13 AM, Kevin Hilman >>>>><khilman@xxxxxxxxxxxxxxxxxxx> wrote: >>>>>> Eric Miao <eric.y.miao@xxxxxxxxx> writes: >>>>>>> On Thu, Sep 24, 2009 at 7:28 AM, Kevin Hilman >>>>>>> <khilman@xxxxxxxxxxxxxxxxxxx> wrote: >>>>>>>> Mikael Pettersson wrote: >>>>>>>>> Eric Miao writes: >>>>>>>>> > On Wed, Sep 23, 2009 at 9:50 AM, Kevin Hilman >>>>>>>>> > <khilman@xxxxxxxxxxxxxxxxxxx> wrote: >>>>>>>>> > > On ARM platforms, power management can be very platform specific. >>>>>>>>> > > This patch allows ARM subarches to extend the platform_device >>>>>>>>> > > pdev_archdata for each subarch by creating a new struct pdev_machdata >>>>>>>>> > > and allowing each subarch to customize it as needed. >>> >>>>>Do you remember what happened with this patch? >>>> >>>> I don't have all the details in front of me because I'm on my phone, >>>> but I advised against pdev_archdata because it is >>>> multiplatform-unfriendly. >>> >>> Ok, I did not expect that. =) But after thinking a bit it does make >>> sense. I wonder what my options are. I'm not so fond of the idea to >>> wrap the platform devices - that's not more multi-platform friendly, >>> is it? >> >> [sorry for the lag, been on vacation] >> >> Wrapping is more multi-platform friendly because only platform-specific >> code accesses the wrapped code. It's also logically consistent as >> a struct device is contained by a platform_device which is then >> contained by an omap_device (in our case.) Only OMAP-specific code >> ever knows about or touches that layer. > > (I just noticed this; will also reply on the other thread so it is > recorded in the public record) But it is also really dangerous; > particularly in the case of dynamically allocated platform_devices. > When handed a random platform_device pointer, you have absolutely *no* > idea whether or not it is valid to dereference a pointer at a lower > address from the platform_device pointer. It is very likely that > there will be other code in the system that will register > platform_devices without the omap_device wrapper. > >>> How about using devres and platform bus notifiers? >> >> That seems fine too, and probably better if the amount of data/code you need >> is small. In the OMAP case, it's rather complicated so it's cleaner >> IMHO to keep it in a separate omap_device layer and struct. > > but it is safe > /me is beaten into submission. ;) OK, it would not be too much work to move the OMAP implementation to devres + notifiers either. I can give it a spin. Kevin _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
