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>

1 files changed, 12 insertions, 3 deletions

diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 2c0b6630f8ba..99181c8f023e 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -386,11 +386,20 @@ int acpi_pm_device_sleep_state(struct device *dev, int wake, int *d_min_p)
         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)