Re: [PATCH 1/4] PCI: allow MSI chip providers to implement their own multiple MSI setup

[Lucas Stach <l.stach@pengutronix.de>]

Hi Pratyush,

Am Freitag, den 13.06.2014, 11:12 +0530 schrieb Pratyush Anand:
>  Hi Lucas,
> 
> 
> On Thu, Jun 5, 2014 at 8:16 PM, Lucas Stach <l.stach@pengutronix.de> wrote:
> > Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> > ---
> >  drivers/pci/msi.c   | 3 +++
> >  include/linux/msi.h | 2 ++
> >  2 files changed, 5 insertions(+)
> >
> > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> > index 27a7e67ddfe4..c45399d3061a 100644
> > --- a/drivers/pci/msi.c
> > +++ b/drivers/pci/msi.c
> > @@ -68,9 +68,12 @@ int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
> >
> >  int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
> >  {
> > +       struct msi_chip *chip = dev->bus->msi;
> >         struct msi_desc *entry;
> >         int ret;
> >
> > +       if (chip && chip->setup_irqs)
> 
> I think, you should also check here for nvec > 1

No, nvec == 1 is just a special case and is perfectly valid.
> 
> > +               return chip->setup_irqs(chip, dev, nvec, type);
> 
> Before return, shouldn't we set chip_data for all desc->irq?

Setting chip_data is done in the MSI irq domains map callback and is the
same for single or multiple MSI setup. No need to do anything special
here.

> >         /*
> >          * If an architecture wants to support multiple MSI, it needs to
> >          * override arch_setup_msi_irqs()
> 
> This comment can be modified like "If an architecture wants
> to support multiple MSI, it needs to either override arch_setup_msi_irqs()
> or provide support of setup_irqs."
> 
Right, I'll extend that comment for v2.

Regards,
Lucas

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