On Fri, Aug 16, 2013 at 02:06:37PM -0700, Greg Kroah-Hartman wrote: > On Fri, Aug 16, 2013 at 10:39:21PM +0200, Thierry Reding wrote: > > +static DEFINE_MUTEX(device_early_mutex); > > +static LIST_HEAD(device_early_list); > > +static bool device_is_early = true; > > + > > +/* > > + * Keep a list of early registered devices so that they can be fully > > + * registered at a later point in time. > > + */ > > +static void device_early_add(struct device *dev) > > __init? Yes. > > +{ > > + mutex_lock(&device_early_mutex); > > + list_add_tail(&dev->p->early, &device_early_list); > > + mutex_unlock(&device_early_mutex); > > +} > > + > > +/* > > + * Mark the early device registration phase as completed. > > + */ > > +int __init device_early_init(void) > > +{ > > + device_is_early = false; > > + > > + return 0; > > +} > > + > > +/* > > + * Fixup platform devices instantiated from device tree. The problem is > > + * that since early registration happens before interrupt controllers > > + * have been setup, the OF core code won't know how to map interrupts. > > + */ > > +int __init platform_device_early_fixup(struct platform_device *pdev) > > This shouldn't be in this file, because: > > > +/* > > + * Fully register early devices. > > + */ > > +int __init device_early_done(void) > > +{ > > + struct device_private *private; > > + > > + list_for_each_entry(private, &device_early_list, early) { > > + struct device *dev = private->device; > > + int err; > > + > > + if (dev->bus == &platform_bus_type) { > > Why special case the platform bus? We are trying to move things off of > the platform bus, don't make it harder to do that :) I heard about that, but I must have missed the thread where this was discussed. Can you point me to it? > > + struct platform_device *pdev = to_platform_device(dev); > > + > > + err = platform_device_early_fixup(pdev); > > + if (err < 0) > > + dev_err(&pdev->dev, > > + "failed to fixup device %s: %d\n", > > + dev_name(&pdev->dev), err); > > + } > > You should just have a bus callback that can be made here that, if > present, can be called. That way any bus can handle this type of thing, > not just the platform one. You mean something like an .early_fixup() in struct bus_type? That would indeed be much cleaner. As I mentioned this is a very early prototype and this particular hunk exists specifically to fixup the platform devices created by the device tree helpers so that the kernel actually boots to the login prompt. > Not that I really like the whole idea anyway, but I doubt there's much I > can do about it... Well, getting feedback from you and others is precisely the reason why I wanted to post this early. There must be a reason why you don't like it, so perhaps you can share your thoughts and we can mould this into something that you'd be more comfortable with. To be honest I don't particularly like it either. It's very hackish for core code. But on the other hand there are a few device/driver ordering problems that this (or something similar) would help solve. I'm certainly open to discuss alternatives and perhaps there's a much cleaner way to solve the problem. Thierry
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