From 31c2b8153c58f11ddb80dfd392c16f13c2d709c6 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 22 May 2014 17:07:43 -0600 Subject: PCI: Add support for DMA alias quirks Some devices are broken and use a requester ID other than their physical devfn. Add a byte, using an existing gap in the pci_dev structure, to store an alternate "alias" devfn. A bit in the dev_flags tells us when this is valid. We then add the alias as one more step in the pci_for_each_dma_alias() iterator. Tested-by: George Spelvin Tested-by: Pat Erley Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas --- drivers/pci/search.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/pci/search.c') diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 5601cdb8bbb3..2c19f3f40621 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -37,6 +37,17 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, if (ret) return ret; + /* + * If the device is broken and uses an alias requester ID for + * DMA, iterate over that too. + */ + if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) { + ret = fn(pdev, PCI_DEVID(pdev->bus->number, + pdev->dma_alias_devfn), data); + if (ret) + return ret; + } + for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) { struct pci_dev *tmp; -- cgit