[Patch V3 34/37] x86, irq, ACPI: release IOAPIC pin when PCI device is disabled

[Jiang Liu <jiang.liu@linux.intel.com>]

Release IOAPIC pin associated with PCI device when the PCI device
is disabled.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
 arch/x86/kernel/acpi/boot.c |   28 ++++++++++++++++++++++++++++
 drivers/acpi/pci_irq.c      |    3 ++-
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 0592c38d9952..c8e8fe67bbc8 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -313,9 +313,11 @@ static void  mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger,
 				    u32 gsi);
 static int mp_register_gsi(struct device *dev, u32 gsi, int trigger,
 			   int polarity);
+static void mp_unregister_gsi(u32 gsi);
 
 static struct irq_domain_ops acpi_irqdomain_ops = {
 	.map = mp_irqdomain_map,
+	.unmap = mp_irqdomain_unmap,
 };
 
 static struct irq_domain *acpi_create_irqdomain(int idx, void *arg)
@@ -541,8 +543,16 @@ static int acpi_register_gsi_ioapic(struct device *dev, u32 gsi,
 	return irq;
 }
 
+static void acpi_unregister_gsi_ioapic(u32 gsi)
+{
+#ifdef CONFIG_X86_IO_APIC
+	mp_unregister_gsi(gsi);
+#endif
+}
+
 int (*__acpi_register_gsi)(struct device *dev, u32 gsi,
 			   int trigger, int polarity) = acpi_register_gsi_pic;
+void (*__acpi_unregister_gsi)(u32 gsi) = NULL;
 
 #ifdef CONFIG_ACPI_SLEEP
 int (*acpi_suspend_lowlevel)(void) = x86_acpi_suspend_lowlevel;
@@ -562,6 +572,8 @@ EXPORT_SYMBOL_GPL(acpi_register_gsi);
 
 void acpi_unregister_gsi(u32 gsi)
 {
+	if (__acpi_unregister_gsi)
+		(*__acpi_unregister_gsi)(gsi);
 }
 EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
 
@@ -569,6 +581,7 @@ static void __init acpi_set_irq_model_ioapic(void)
 {
 	acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
 	__acpi_register_gsi = acpi_register_gsi_ioapic;
+	__acpi_unregister_gsi = acpi_unregister_gsi_ioapic;
 	acpi_ioapic = 1;
 }
 
@@ -1050,6 +1063,21 @@ static int mp_register_gsi(struct device *dev, u32 gsi, int trigger,
 	return irq;
 }
 
+static void mp_unregister_gsi(u32 gsi)
+{
+	int irq;
+
+	if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC)
+		return;
+
+	if (acpi_gbl_FADT.sci_interrupt == gsi)
+		return;
+
+	irq = mp_map_gsi_to_irq(gsi, 0);
+	if (irq > 0)
+		mp_unmap_irq(irq);
+}
+
 /*
  * Parse IOAPIC related entries in MADT
  * returns 0 on success, < 0 on error
diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index 9c62340c2360..6ba463ceccc6 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -498,5 +498,6 @@ void acpi_pci_irq_disable(struct pci_dev *dev)
 	 */
 
 	dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
-	acpi_unregister_gsi(gsi);
+	if (gsi >= 0 && dev->irq > 0)
+		acpi_unregister_gsi(gsi);
 }
-- 
1.7.10.4