diff options
| -rw-r--r-- | drivers/ata/ahci.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index ba5f11cebee2..ed311a040fed 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1418,21 +1418,24 @@ static int ahci_init_msi(struct pci_dev *pdev, unsigned int n_ports, * Message mode could be enforced. In this case assume that advantage * of multipe MSIs is negated and use single MSI mode instead. */ - nvec = pci_alloc_irq_vectors(pdev, n_ports, INT_MAX, - PCI_IRQ_MSIX | PCI_IRQ_MSI); - if (nvec > 0) { - if (!(readl(hpriv->mmio + HOST_CTL) & HOST_MRSM)) { - hpriv->get_irq_vector = ahci_get_irq_vector; - hpriv->flags |= AHCI_HFLAG_MULTI_MSI; - return nvec; - } + if (n_ports > 1) { + nvec = pci_alloc_irq_vectors(pdev, n_ports, INT_MAX, + PCI_IRQ_MSIX | PCI_IRQ_MSI); + if (nvec > 0) { + if (!(readl(hpriv->mmio + HOST_CTL) & HOST_MRSM)) { + hpriv->get_irq_vector = ahci_get_irq_vector; + hpriv->flags |= AHCI_HFLAG_MULTI_MSI; + return nvec; + } - /* - * Fallback to single MSI mode if the controller enforced MRSM - * mode. - */ - printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n"); - pci_free_irq_vectors(pdev); + /* + * Fallback to single MSI mode if the controller + * enforced MRSM mode. + */ + printk(KERN_INFO + "ahci: MRSM is on, fallback to single MSI\n"); + pci_free_irq_vectors(pdev); + } } /* |