[ACPI] suspend/resume ACPI PCI Interrupt Links

Add reference count and disable ACPI PCI Interrupt Link
when no device still uses it.

Warn when drivers have not released Link at suspend time.

http://bugzilla.kernel.org/show_bug.cgi?id=3469

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 59 insertions, 26 deletions

diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index 8093f2e00321..c536ccfc5413 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -269,7 +269,51 @@ acpi_pci_irq_del_prt (int segment, int bus)
 /* --------------------------------------------------------------------------
                           PCI Interrupt Routing Support
    -------------------------------------------------------------------------- */
+typedef int (*irq_lookup_func)(struct acpi_prt_entry *, int *, int *, char **);
 
+static int
+acpi_pci_allocate_irq(struct acpi_prt_entry *entry,
+        int     *edge_level,
+        int     *active_high_low,
+        char    **link)
+{
+        int     irq;
+
+        ACPI_FUNCTION_TRACE("acpi_pci_allocate_irq");
+
+        if (entry->link.handle) {
+                irq = acpi_pci_link_allocate_irq(entry->link.handle,
+                        entry->link.index, edge_level, active_high_low, link);
+                if (irq < 0) {
+                        ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ link routing entry\n"));
+                        return_VALUE(-1);
+                }
+        } else {
+                irq = entry->link.index;
+                *edge_level = ACPI_LEVEL_SENSITIVE;
+                *active_high_low = ACPI_ACTIVE_LOW;
+        }
+
+        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
+        return_VALUE(irq);
+}
+
+static int
+acpi_pci_free_irq(struct acpi_prt_entry *entry,
+        int     *edge_level,
+        int     *active_high_low,
+        char    **link)
+{
+        int     irq;
+
+        ACPI_FUNCTION_TRACE("acpi_pci_free_irq");
+        if (entry->link.handle) {
+                irq = acpi_pci_link_free_irq(entry->link.handle);
+        } else {
+                irq = entry->link.index;
+        }
+        return_VALUE(irq);
+}
 /*
  * acpi_pci_irq_lookup
  * success: return IRQ >= 0
@@ -282,12 +326,13 @@ acpi_pci_irq_lookup (
         int                     pin,
         int                     *edge_level,
         int                     *active_high_low,
-        char                    **link)
+        char                    **link,
+        irq_lookup_func         func)
 {
         struct acpi_prt_entry   *entry = NULL;
         int segment = pci_domain_nr(bus);
         int bus_nr = bus->number;
-        int irq;
+        int ret;
 
         ACPI_FUNCTION_TRACE("acpi_pci_irq_lookup");
 
@@ -301,22 +346,8 @@ acpi_pci_irq_lookup (
                 return_VALUE(-1);
         }
         
-        if (entry->link.handle) {
-                irq = acpi_pci_link_get_irq(entry->link.handle,
-                        entry->link.index, edge_level, active_high_low, link);
-                if (irq < 0) {
-                        ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ link routing entry\n"));
-                        return_VALUE(-1);
-                }
-        } else {
-                irq = entry->link.index;
-                *edge_level = ACPI_LEVEL_SENSITIVE;
-                *active_high_low = ACPI_ACTIVE_LOW;
-        }
-
-        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
-
-        return_VALUE(irq);
+        ret = func(entry, edge_level, active_high_low, link);
+        return_VALUE(ret);
 }
 
 /*
@@ -330,7 +361,8 @@ acpi_pci_irq_derive (
         int                     pin,
         int                     *edge_level,
         int                     *active_high_low,
-        char                    **link)
+        char                    **link,
+        irq_lookup_func         func)
 {
         struct pci_dev          *bridge = dev;
         int                     irq = -1;
@@ -363,7 +395,7 @@ acpi_pci_irq_derive (
                 }
 
                 irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn),
-                        pin, edge_level, active_high_low, link);
+                        pin, edge_level, active_high_low, link, func);
         }
 
         if (irq < 0) {
@@ -415,7 +447,7 @@ acpi_pci_irq_enable (
          * values override any BIOS-assigned IRQs set during boot.
          */
         irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
-                &edge_level, &active_high_low, &link);
+                &edge_level, &active_high_low, &link, acpi_pci_allocate_irq);
 
         /*
          * If no PRT entry was found, we'll try to derive an IRQ from the
@@ -423,7 +455,7 @@ acpi_pci_irq_enable (
          */
         if (irq < 0)
                 irq = acpi_pci_irq_derive(dev, pin, &edge_level,
-                        &active_high_low, &link);
+                        &active_high_low, &link, acpi_pci_allocate_irq);
  
         /*
          * No IRQ known to the ACPI subsystem - maybe the BIOS / 
@@ -461,7 +493,9 @@ acpi_pci_irq_enable (
 EXPORT_SYMBOL(acpi_pci_irq_enable);
 
 
-#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+/* FIXME: implement x86/x86_64 version */
+void __attribute__((weak)) acpi_unregister_gsi(u32 i) {}
+
 void
 acpi_pci_irq_disable (
         struct pci_dev          *dev)
@@ -488,14 +522,14 @@ acpi_pci_irq_disable (
          * First we check the PCI IRQ routing table (PRT) for an IRQ.
          */
         gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
-                                  &edge_level, &active_high_low, NULL);
+                        &edge_level, &active_high_low, NULL, acpi_pci_free_irq);
         /*
          * If no PRT entry was found, we'll try to derive an IRQ from the
          * device's parent bridge.
          */
         if (gsi < 0)
                 gsi = acpi_pci_irq_derive(dev, pin,
-                                          &edge_level, &active_high_low, NULL);
+                        &edge_level, &active_high_low, NULL, acpi_pci_free_irq);
         if (gsi < 0)
                 return_VOID;
 
@@ -511,4 +545,3 @@ acpi_pci_irq_disable (
 
         return_VOID;
 }
-#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */