sony-laptop: Invoke _INI for SNC devices that provide it

Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/misc/sony-laptop.c b/drivers/misc/sony-laptop.c
index 43315be..5300cad 100644
--- a/drivers/misc/sony-laptop.c
+++ b/drivers/misc/sony-laptop.c
@@ -864,6 +864,15 @@
 
 	sony_nc_acpi_handle = device->handle;
 
+	/* read device status */
+	result = acpi_bus_get_status(device);
+	/* bail IFF the above call was successful and the device is not present */
+	if (!result && !device->status.present) {
+		dprintk("Device not present\n");
+		result = -ENODEV;
+		goto outwalk;
+	}
+
 	if (debug) {
 		status = acpi_walk_namespace(ACPI_TYPE_METHOD, sony_nc_acpi_handle,
 					     1, sony_walk_callback, NULL, NULL);
@@ -874,6 +883,15 @@
 		}
 	}
 
+	/* try to _INI the device if such method exists (ACPI spec 3.0-6.5.1
+	 * should be respected as we already checked for the device presence above */
+	if (ACPI_SUCCESS(acpi_get_handle(sony_nc_acpi_handle, METHOD_NAME__INI, &handle))) {
+		dprintk("Invoking _INI\n");
+		if (ACPI_FAILURE(acpi_evaluate_object(sony_nc_acpi_handle, METHOD_NAME__INI,
+						NULL, NULL)))
+			dprintk("_INI Method failed\n");
+	}
+
 	/* setup input devices and helper fifo */
 	result = sony_laptop_setup_input();
 	if (result) {
@@ -886,7 +904,7 @@
 					     ACPI_DEVICE_NOTIFY,
 					     sony_acpi_notify, NULL);
 	if (ACPI_FAILURE(status)) {
-		printk(KERN_WARNING DRV_PFX "unable to install notify handler\n");
+		printk(KERN_WARNING DRV_PFX "unable to install notify handler (%u)\n", status);
 		result = -ENODEV;
 		goto outinput;
 	}