ACPI: Fix acpi_pm_device_sleep_state()

Fix acpi_pm_device_sleep_state() to return the value returned
by _SxD if the device is supposed to wake up the system from
given sleep state and the evaluation of _SxW fails (e.g. _SxW
is not present).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 2c0b663..99181c8 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -386,11 +386,20 @@
 	if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 	    (wake && adev->wakeup.state.enabled &&
 	     adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
+		acpi_status status;
+
 		acpi_method[3] = 'W';
-		acpi_evaluate_integer(handle, acpi_method, NULL, &d_max);
-		/* Sanity check */
-		if (d_max < d_min)
+		status = acpi_evaluate_integer(handle, acpi_method, NULL,
+						&d_max);
+		if (ACPI_FAILURE(status)) {
+			d_max = d_min;
+		} else if (d_max < d_min) {
+			/* Warn the user of the broken DSDT */
+			printk(KERN_WARNING "ACPI: Wrong value from %s\n",
+				acpi_method);
+			/* Sanitize it */
 			d_min = d_max;
+		}
 	}
 
 	if (d_min_p)