ACPI/PCI: PCI MSI _OSC support capabilities called when root bridge added

The _OSC capability OSC_MSI_SUPPORT is set when the root bridge is added
with pci_acpi_osc_support(), so we no longer need to do it in the PCI
MSI driver.  Also adds the function pci_msi_enabled, which returns true
if pci=nomsi is not on the kernel command-line.
Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/acpi/pci_root.c

@@ -350,6 +350,8 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
 	if (pcie_aspm_enabled())
 		flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 			OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
+	if (pci_msi_enabled())
+		flags |= OSC_MSI_SUPPORT;
 	if (flags != base_flags)
 		pci_acpi_osc_support(device->handle, flags);
 

drivers/pci/msi.c

@@ -776,28 +776,19 @@ void pci_no_msi(void)
 	pci_msi_enable = 0;
 }
 
-void pci_msi_init_pci_dev(struct pci_dev *dev)
-{
-	INIT_LIST_HEAD(&dev->msi_list);
-}
-
-#ifdef CONFIG_ACPI
-#include <linux/acpi.h>
-#include <linux/pci-acpi.h>
-static void __devinit msi_acpi_init(void)
+/**
+ * pci_msi_enabled - is MSI enabled?
+ *
+ * Returns true if MSI has not been disabled by the command-line option
+ * pci=nomsi.
+ **/
+int pci_msi_enabled(void)
 {
-	if (acpi_pci_disabled)
-		return;
-	pci_osc_support_set(OSC_MSI_SUPPORT);
-	pcie_osc_support_set(OSC_MSI_SUPPORT);
+	return pci_msi_enable;
 }
-#else
-static inline void msi_acpi_init(void) { }
-#endif /* CONFIG_ACPI */
+EXPORT_SYMBOL(pci_msi_enabled);
 
-void __devinit msi_init(void)
+void pci_msi_init_pci_dev(struct pci_dev *dev)
 {
-	if (!pci_msi_enable)
-		return;
-	msi_acpi_init();
+	INIT_LIST_HEAD(&dev->msi_list);
 }

drivers/pci/pci.c

@@ -2105,8 +2105,6 @@ static int __devinit pci_init(void)
 		pci_fixup_device(pci_fixup_final, dev);
 	}
 
-	msi_init();
-
 	return 0;
 }
 

drivers/pci/pci.h

@@ -102,11 +102,9 @@ extern unsigned int pci_pm_d3_delay;
 #ifdef CONFIG_PCI_MSI
 void pci_no_msi(void);
 extern void pci_msi_init_pci_dev(struct pci_dev *dev);
-extern void __devinit msi_init(void);
 #else
 static inline void pci_no_msi(void) { }
 static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { }
-static inline void msi_init(void) { }
 #endif
 
 #ifdef CONFIG_PCIEAER

include/linux/pci.h

@@ -779,6 +779,10 @@ static inline void msi_remove_pci_irq_vectors(struct pci_dev *dev)
 
 static inline void pci_restore_msi_state(struct pci_dev *dev)
 { }
+static inline int pci_msi_enabled(void)
+{
+	return 0;
+}
 #else
 extern int pci_enable_msi(struct pci_dev *dev);
 extern void pci_msi_shutdown(struct pci_dev *dev);
@@ -789,6 +793,7 @@ extern void pci_msix_shutdown(struct pci_dev *dev);
 extern void pci_disable_msix(struct pci_dev *dev);
 extern void msi_remove_pci_irq_vectors(struct pci_dev *dev);
 extern void pci_restore_msi_state(struct pci_dev *dev);
+extern int pci_msi_enabled(void);
 #endif
 
 #ifndef CONFIG_PCIEASPM