drm/radeon: Only call drm_vblank_on/off between drm_vblank_init/cleanup

Prevents the

	if (WARN_ON(pipe >= dev->num_crtcs))

in drm_vblank_on/off from triggering if acceleration fails to
initialize, in which case we call drm_vblank_cleanup.
Reported-and-Tested-by: Julian Margetson <runaway@candw.ms>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/atombios_crtc.c

@@ -275,13 +275,15 @@ void atombios_crtc_dpms(struct drm_crtc *crtc, int mode)
 		if (ASIC_IS_DCE3(rdev) && !ASIC_IS_DCE6(rdev))
 			atombios_enable_crtc_memreq(crtc, ATOM_ENABLE);
 		atombios_blank_crtc(crtc, ATOM_DISABLE);
-		drm_vblank_on(dev, radeon_crtc->crtc_id);
+		if (dev->num_crtcs > radeon_crtc->crtc_id)
+			drm_vblank_on(dev, radeon_crtc->crtc_id);
 		radeon_crtc_load_lut(crtc);
 		break;
 	case DRM_MODE_DPMS_STANDBY:
 	case DRM_MODE_DPMS_SUSPEND:
 	case DRM_MODE_DPMS_OFF:
-		drm_vblank_off(dev, radeon_crtc->crtc_id);
+		if (dev->num_crtcs > radeon_crtc->crtc_id)
+			drm_vblank_off(dev, radeon_crtc->crtc_id);
 		if (radeon_crtc->enabled)
 			atombios_blank_crtc(crtc, ATOM_ENABLE);
 		if (ASIC_IS_DCE3(rdev) && !ASIC_IS_DCE6(rdev))

drivers/gpu/drm/radeon/radeon_legacy_crtc.c

@@ -331,13 +331,15 @@ static void radeon_crtc_dpms(struct drm_crtc *crtc, int mode)
 									 RADEON_CRTC_DISP_REQ_EN_B));
 			WREG32_P(RADEON_CRTC_EXT_CNTL, crtc_ext_cntl, ~(mask | crtc_ext_cntl));
 		}
-		drm_vblank_on(dev, radeon_crtc->crtc_id);
+		if (dev->num_crtcs > radeon_crtc->crtc_id)
+			drm_vblank_on(dev, radeon_crtc->crtc_id);
 		radeon_crtc_load_lut(crtc);
 		break;
 	case DRM_MODE_DPMS_STANDBY:
 	case DRM_MODE_DPMS_SUSPEND:
 	case DRM_MODE_DPMS_OFF:
-		drm_vblank_off(dev, radeon_crtc->crtc_id);
+		if (dev->num_crtcs > radeon_crtc->crtc_id)
+			drm_vblank_off(dev, radeon_crtc->crtc_id);
 		if (radeon_crtc->crtc_id)
 			WREG32_P(RADEON_CRTC2_GEN_CNTL, mask, ~(RADEON_CRTC2_EN | mask));
 		else {