From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kenji Kaneshige Date: Fri, 24 Sep 2004 06:29:14 +0000 Subject: Re: [ACPI] [PATCH] PCI IRQ resource deallocation support [2/3] Message-Id: <4153BEBA.5030202@jp.fujitsu.com> List-Id: References: <414FEBDB.2050201@soft.fujitsu.com> <200409210857.59457.bjorn.helgaas@hp.com> <4150D458.3050400@jp.fujitsu.com> <20040924.145229.108814142.t-kochi@bq.jp.nec.com> In-Reply-To: <20040924.145229.108814142.t-kochi-UDFczIW9X1d8UrSeD/g0lQ@public.gmane.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Takayoshi Kochi Cc: bjorn.helgaas-VXdhtT5mjnY@public.gmane.org, acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, kaneshige.kenji-tPnzhWqfZ96MLkP6nYsO9A@public.gmane.org, akpm-3NddpPZAyC0@public.gmane.org, greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org, len.brown-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, tony.luck-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ia64-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Hi Takayoshi, Thank you for feedback. Takayoshi Kochi wrote: >> > Why do we need to fiddle with dev->irq? I think it should >> > just be undefined after acpi_pci_irq_disable(). >> >> I had been considering what the "undefined dev->irq" was. >> In fact, I had other ideas that was clearing it by zero or >> -1 (0xffffffff). But I didn't know if we can use these values >> as a undefined IRQ number. So I'm clearing it by the value >> which was assigned by PCI core code (pci_read_irq()) before >> acpi_pci_irq_enable() was called. > > I think it has little sense in restoring value from the configuration > space to dev->irq or clearing it. > > If we do preventive programming, it may be worth > trying to define some magic constant (e.g. PCI_UNDEFINED_IRQ) and > panic/BUG when the irq is being enabled. > Otherwise, leaving dev->irq as it is would be ok. Hmm, I think you are right. I'll change my patch to leave dev->irq as it is. And then I'll investigate about defining PCI_UNDEFINED_IRQ. In fact, I posted updated patches a little before. I'll re-post it with your feedback :-) Thanks, Kenji Kaneshige