From 06cf56e497c8c1469b0931caa7d5b1d827655fe2 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Sat, 21 Dec 2013 08:33:26 -0700 Subject: [PATCH] PCI: Add pci_bus_address() to get bus address of a BAR We store BAR information as a struct resource, which contains the CPU address, not the bus address. Drivers often need the bus address, and there's currently no convenient way to get it, so they often read the BAR directly, or use the resource address (which doesn't work if there's any translation between CPU and bus addresses). Add pci_bus_address() to make this convenient. Signed-off-by: Bjorn Helgaas --- include/linux/pci.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/include/linux/pci.h b/include/linux/pci.h index bf32412704a7..966b286b5d53 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1077,6 +1077,14 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus, resource_size_t), void *alignf_data); +static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar) +{ + struct pci_bus_region region; + + pcibios_resource_to_bus(pdev->bus, ®ion, &pdev->resource[bar]); + return region.start; +} + /* Proper probing supporting hot-pluggable devices */ int __must_check __pci_register_driver(struct pci_driver *, struct module *, const char *mod_name); -- 2.20.1