[PATCH] drm/nouveau/kms/nv50-: use DRM_NOUVEAU_BACKLIGHT consistently

[trix at redhat.com]

From: Tom Rix <trix at redhat.com>

A build error when DRM_NOUVEAU_BACKLIGHT is not defined
disp.c:1665:52: error: 'struct nouveau_connector' has no
  member named 'backlight'

Use ifdef's similar to elsewhere in disp.c to conditionally
use the new backlight support.

Move scope of drm to where it is used, inside the backlight error
reporting.

Remove shadow ret decl.

Fixes: 6eca310e8924 ("drm/nouveau/kms/nv50-: Add basic DPCD backlight support for nouveau")
Signed-off-by: Tom Rix <trix at redhat.com>
---
 drivers/gpu/drm/nouveau/dispnv50/disp.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 093e1f7163b31..6e957041edfb5 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1659,23 +1659,28 @@ static void
 nv50_sor_atomic_disable(struct drm_encoder *encoder, struct drm_atomic_state *state)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
-	struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(nv_encoder->crtc);
 	struct nouveau_connector *nv_connector = nv50_outp_get_old_connector(state, nv_encoder);
+#ifdef CONFIG_DRM_NOUVEAU_BACKLIGHT
 	struct nouveau_backlight *backlight = nv_connector->backlight;
+#endif
 	struct drm_dp_aux *aux = &nv_connector->aux;
 	int ret;
 	u8 pwr;
 
+#ifdef CONFIG_DRM_NOUVEAU_BACKLIGHT
 	if (backlight && backlight->uses_dpcd) {
 		ret = drm_edp_backlight_disable(aux, &backlight->edp_info);
-		if (ret < 0)
+		if (ret < 0) {
+			struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
 			NV_ERROR(drm, "Failed to disable backlight on [CONNECTOR:%d:%s]: %d\n",
 				 nv_connector->base.base.id, nv_connector->base.name, ret);
+		}
 	}
+#endif
 
 	if (nv_encoder->dcb->type == DCB_OUTPUT_DP) {
-		int ret = drm_dp_dpcd_readb(aux, DP_SET_POWER, &pwr);
+		ret = drm_dp_dpcd_readb(aux, DP_SET_POWER, &pwr);
 
 		if (ret == 0) {
 			pwr &= ~DP_SET_POWER_MASK;
-- 
2.26.3