On Wed, 24 Mar 2010, Ian Campbell wrote: > On Mon, 2010-03-22 at 10:19 +0000, Thomas Gleixner wrote: > > On Sun, 21 Mar 2010, Yinghai Lu wrote: > > > > > From: Ian Campbell <ian.campb...@citrix.com> > > > > > > Move arch_init_copy_chip_data and arch_free_chip_data into function > > > pointers in struct irq_chip since they operate on irq_desc->chip_data. > > > > Not sure about that. These functions are solely used by x86 and there > > is really no need to generalize them. > > I thought the idea of struct irq_chip was to allow the potential for > multiple IRQ controllers in a system? Given that it seems that struct > irq_desc->chip_data ought to be available for use by whichever struct > irq_chip is managing a given interrupt. At the moment this is not > possible because we step around the abstraction using these arch_* > methods.
Right, but you have exactly _ONE_ irq_chip associated to an irq_desc, but that same irq_chip can be associated to several irq_descs. So irq_desc->data is there to provide data for the irq_chip functions depending on what irq they handle (e.g. base_address ...). irq_desc->chip_data is set when the irq_chip is assigned to the irq_desc. So there is no point in having functions in irq_chip to set irq_desc->chip_data. Thanks, tglx _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev