of/pci: Fix pci_address_to_pio() conversion of CPU address to I/O port

commit 5dbb4c6167229c8d4f528e8ec26699a7305000a3 upstream.

41f8bba7f555 ("of/pci: Add pci_register_io_range() and
pci_pio_to_address()") added support for systems with several I/O ranges
described by OF bindings.  It modified pci_address_to_pio() look up the
io_range for a given CPU physical address, but the conversion was wrong.

Fix the conversion of address to I/O port.

[bhelgaas: changelog]
Fixes: 41f8bba7f555 ("of/pci: Add pci_register_io_range() and pci_pio_to_address()")
Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 78a7dcbec7d8..6906a3f61bd8 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -765,7 +765,7 @@ unsigned long __weak pci_address_to_pio(phys_addr_t address)
         spin_lock(&io_range_lock);
         list_for_each_entry(res, &io_range_list, list) {
                 if (address >= res->start && address < res->start + res->size) {
-                        addr = res->start - address + offset;
+                        addr = address - res->start + offset;
                         break;
                 }
                 offset += res->size;