Messages in this thread | | | Date | Fri, 30 Apr 2004 18:48:27 -0700 | From | Greg KH <> | Subject | Re: [PATCH] Hotplug for device power state changes |
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On Fri, Apr 30, 2004 at 06:16:22PM -0700, Todd Poynor wrote: > Greg KH wrote: > >On Fri, Apr 30, 2004 at 12:59:40PM -0700, Todd Poynor wrote: > > > >>* Changes to kobject to allow kobject hotplug to optionally be > >>synchronous if desired. I'd assume this is a new hotplug_ops field. > > > > > >Ick. > > Is the objection to using kobject for synchronous hotplug events, or to > using a hotplug_ops flag to indicate which kind is needed? Would the > addition of a kobject_hotplug_sync function be better? Or a > handshake-like interface as with firmware downloads?
To add an option to the kobject_hotplug() function for a sync call is one thing. To make the option for the main kobject add and remove call to be sync is a horribly misguided thought (the reason why is left as an exercise for the reader...like go read the udev code for many reasons why...)
I don't have an objection to add such a new paramater (or even a new function call like you suggested), just don't go messing with the main kobject hotplug call without thinking everything through :)
> >>* Synchronous hotplug events for system suspend and resume (without > >>individual device notifications). These events can probably be > >>generated by the kobject hotplug methods by the existing power subsys > >>(once the above enhancement is in place). > > > > > >But why? Do you really need this? Have you actually tested a system to > >see if it is needed? > > This is something that was requested of me by others who build Linux > into consumer electronics devices. Perhaps some of the interested > parties may speak up here to add more insight.
Please encourage them to speak up. I hear _nothing_ from any embedded developers, and I am really interested in how the driver model and hotplug works (or doesn't) for them. Without that feedback, we are in the dark as to what their needs/hates are.
thanks,
greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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