From: Christoph Hellwig <hch@lst.de>
Date: Thu, 11 Aug 2016 14:11:05 +0000 (-0700)
Subject: PCI: Call pci_intx() when using legacy interrupts in pci_alloc_irq_vectors()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5d0bdf2867825a92c0a563957a2fb059149ab0d4;p=linux.git

PCI: Call pci_intx() when using legacy interrupts in pci_alloc_irq_vectors()

ahci currently insists on an explicit call to pci_intx() before falling
back from MSI or MSI-X to legacy IRQs.  As pci_intx() is a no-op if the
command register already contains the right value it seems safe and useful
to add this call to pci_alloc_irq_vectors() so that ahci can just use
pci_alloc_irq_vectors().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 9233e7f62f474..593698e11f963 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -1200,8 +1200,11 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
 	}
 
 	/* use legacy irq if allowed */
-	if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1)
+	if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1) {
+		pci_intx(dev, 1);
 		return 1;
+	}
+
 	return vecs;
 }
 EXPORT_SYMBOL(pci_alloc_irq_vectors);