[PATCH 2/4] x86/pci/intel_mid_pci: Fix PCIBIOS_* return code handling

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

intel_mid_pci_irq_enable() uses pci_read_config_byte() that returns
PCIBIOS_* codes. The error handling, however, assumes the codes are
normal errnos because it checks for < 0.

intel_mid_pci_irq_enable() also returns the PCIBIOS_* code back to the
caller but the function is used as the (*pcibios_enable_irq) function
which should return normal errnos.

Convert the error check to plain non-zero check which works for
PCIBIOS_* return codes and convert the PCIBIOS_* return code using
pcibios_err_to_errno() into normal errno before returning it.

Fixes: 5b395e2be6c4 ("x86/platform/intel-mid: Make IRQ allocation a bit more flexible")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: stable@vger.kernel.org
---
 arch/x86/pci/intel_mid_pci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/pci/intel_mid_pci.c b/arch/x86/pci/intel_mid_pci.c
index 8edd62206604..722a33be08a1 100644
--- a/arch/x86/pci/intel_mid_pci.c
+++ b/arch/x86/pci/intel_mid_pci.c
@@ -233,9 +233,9 @@ static int intel_mid_pci_irq_enable(struct pci_dev *dev)
 		return 0;
 
 	ret = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
-	if (ret < 0) {
+	if (ret) {
 		dev_warn(&dev->dev, "Failed to read interrupt line: %d\n", ret);
-		return ret;
+		return pcibios_err_to_errno(ret);
 	}
 
 	id = x86_match_cpu(intel_mid_cpu_ids);
-- 
2.39.2