ACPI: Add _OST support for ACPI CPU hotplug

Changed acpi_processor_hotplug_notify() to call ACPI _OST method
when ACPI CPU hotplug operation has completed.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/processor_driver.c

@@ -701,9 +701,9 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
 {
 	struct acpi_processor *pr;
 	struct acpi_device *device = NULL;
+	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
 	int result;
 
-
 	switch (event) {
 	case ACPI_NOTIFY_BUS_CHECK:
 	case ACPI_NOTIFY_DEVICE_CHECK:
@@ -715,14 +715,18 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
 		if (!is_processor_present(handle))
 			break;
 
-		if (acpi_bus_get_device(handle, &device)) {
+		if (!acpi_bus_get_device(handle, &device))
+			break;
+
 		result = acpi_processor_device_add(handle, &device);
-			if (result)
-				printk(KERN_ERR PREFIX
-					    "Unable to add the device\n");
+		if (result) {
+			printk(KERN_ERR PREFIX "Unable to add the device\n");
 			break;
 		}
+
+		ost_code = ACPI_OST_SC_SUCCESS;
 		break;
+
 	case ACPI_NOTIFY_EJECT_REQUEST:
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "received ACPI_NOTIFY_EJECT_REQUEST\n"));
@@ -736,15 +740,23 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
 		if (!pr) {
 			printk(KERN_ERR PREFIX
 				    "Driver data is NULL, dropping EJECT\n");
-			return;
-		}
-		break;
-	default:
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-				  "Unsupported event [0x%x]\n", event));
 			break;
 		}
 
+		/* REVISIT: update when eject is supported */
+		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
+		break;
+
+	default:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				  "Unsupported event [0x%x]\n", event));
+
+		/* non-hotplug event; possibly handled by other handler */
+		return;
+	}
+
+	/* Inform firmware that the hotplug operation has completed */
+	(void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
 	return;
 }