[PATCH] ahci: don't use MSI when PCI is disabled

[arnd@arndb.de (Arnd Bergmann)]

On Monday 23 November 2015 20:34:30 Arnd Bergmann wrote:
> On Monday 23 November 2015 09:25:38 Dan Williams wrote:
> > 
> > If we had an "static inline ahci_irq_vector(int port)"  helper to
> > compile out the struct msix_entry de-reference would that be
> > sufficient?
> 
> Yes, that is probably a nicer way to do it. We should then also do
> something like this:
> 
> @@ -2510,7 +2513,8 @@ int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht)
>         int irq = hpriv->irq;
>         int rc;
>  
> -       if (hpriv->flags & (AHCI_HFLAG_MULTI_MSI | AHCI_HFLAG_MULTI_MSIX))
> +       if (IS_ENABLED(CONFIG_PCI_MSI) && \
> +           hpriv->flags & (AHCI_HFLAG_MULTI_MSI | AHCI_HFLAG_MULTI_MSIX))
>                 rc = ahci_host_activate_multi_irqs(host, sht);
>         else if (hpriv->flags & AHCI_HFLAG_EDGE_IRQ)
>                 rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,
> 
> which will let gcc leave out the entire ahci_host_activate_multi_irqs()
> function but still flag compile errors in it even if CONFIG_PCI is
> disabled.
> 

Dan, are you going to do the ahci_irq_vector patch, or should we use my
original patch to fix up the build error?

Chen-Yu Tsai just stumbled over the same problem that I noticed, and I'm
sure others have run into it too.

	Arnd