ACPI: PCI: add a helper to convert _PRT INTx pin number to name

This adds a helper function to convert INTx pin numbers from the _PRT
(0, 1, 2, 3) to the pin name ('A', 'B', 'C', 'D').

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 15 insertions, 10 deletions

diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index ea003bab7ecd..5ce1fcf77455 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -60,6 +60,11 @@ struct acpi_prt_list {
 static struct acpi_prt_list acpi_prt;
 static DEFINE_SPINLOCK(acpi_prt_lock);
 
+static inline char pin_name(int pin)
+{
+        return 'A' + pin;
+}
+
 /* --------------------------------------------------------------------------
                          PCI IRQ Routing Table (PRT) Support
    -------------------------------------------------------------------------- */
@@ -174,14 +179,14 @@ do_prt_fixups(struct acpi_prt_entry *entry, struct acpi_pci_routing_table *prt)
                     entry->id.segment == quirk->segment &&
                     entry->id.bus == quirk->bus &&
                     entry->id.device == quirk->device &&
-                    entry->pin + 'A' == quirk->pin &&
+                    pin_name(entry->pin) == quirk->pin &&
                     !strcmp(prt->source, quirk->source) &&
                     strlen(prt->source) >= strlen(quirk->actual_source)) {
                         printk(KERN_WARNING PREFIX "firmware reports "
                                 "%04x:%02x:%02x PCI INT %c connected to %s; "
                                 "changing to %s\n",
                                 entry->id.segment, entry->id.bus,
-                                entry->id.device, 'A' + entry->pin,
+                                entry->id.device, pin_name(entry->pin),
                                 prt->source, quirk->actual_source);
                         strcpy(prt->source, quirk->actual_source);
                 }
@@ -235,8 +240,8 @@ acpi_pci_irq_add_entry(acpi_handle handle,
         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
                               "      %04x:%02x:%02x[%c] -> %s[%d]\n",
                               entry->id.segment, entry->id.bus,
-                              entry->id.device, ('A' + entry->pin), prt->source,
-                              entry->link.index));
+                              entry->id.device, pin_name(entry->pin),
+                              prt->source, entry->link.index));
 
         spin_lock(&acpi_prt_lock);
         list_add_tail(&entry->node, &acpi_prt.entries);
@@ -387,7 +392,7 @@ acpi_pci_irq_lookup(struct pci_bus *bus,
 
         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                           "Searching for _PRT entry for %04x:%02x:%02x[%c]\n",
-                          segment, bus_nr, device, ('A' + pin)));
+                          segment, bus_nr, device, pin_name(pin)));
 
         entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin);
         if (!entry) {
@@ -444,7 +449,7 @@ acpi_pci_irq_derive(struct pci_dev *dev,
 
         if (irq < 0) {
                 dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
-                         'A' + orig_pin);
+                         pin_name(orig_pin));
                 return -1;
         }
 
@@ -511,7 +516,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
          * driver reported one, then use it. Exit in any case.
          */
         if (gsi < 0) {
-                dev_warn(&dev->dev, "PCI INT %c: no GSI", 'A' + pin);
+                dev_warn(&dev->dev, "PCI INT %c: no GSI", pin_name(pin));
                 /* Interrupt Line values above 0xF are forbidden */
                 if (dev->irq > 0 && (dev->irq <= 0xF)) {
                         printk(" - using IRQ %d\n", dev->irq);
@@ -527,7 +532,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
         rc = acpi_register_gsi(gsi, triggering, polarity);
         if (rc < 0) {
                 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
-                         'A' + pin);
+                         pin_name(pin));
                 return rc;
         }
         dev->irq = rc;
@@ -538,7 +543,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
                 link_desc[0] = '\0';
 
         dev_info(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
-                 'A' + pin, link_desc, gsi,
+                 pin_name(pin), link_desc, gsi,
                  (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
                  (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
 
@@ -585,6 +590,6 @@ void acpi_pci_irq_disable(struct pci_dev *dev)
          * (e.g. PCI_UNDEFINED_IRQ).
          */
 
-        dev_info(&dev->dev, "PCI INT %c disabled\n", 'A' + pin);
+        dev_info(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
         acpi_unregister_gsi(gsi);
 }