drm/radeon/kms/pm: don't enable pm if there is only on power state

Just adds overhead when the power state will never change.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index a137ee2..8111264 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -113,7 +113,7 @@ int radeon_pm_init(struct radeon_device *rdev)
 
        INIT_DELAYED_WORK(&rdev->pm.idle_work, radeon_pm_idle_work_handler);
 
 
        INIT_DELAYED_WORK(&rdev->pm.idle_work, radeon_pm_idle_work_handler);
 

-       if (radeon_dynpm != -1 && radeon_dynpm) {
+       if ((radeon_dynpm != -1 && radeon_dynpm) && (rdev->pm.num_power_states > 1)) {

                rdev->pm.state = PM_STATE_PAUSED;
                DRM_INFO("radeon: dynamic power management enabled\n");
        }
                rdev->pm.state = PM_STATE_PAUSED;
                DRM_INFO("radeon: dynamic power management enabled\n");
        }