imx-drm: parallel-display: Fix DPMS default state.

If connector->dpms is left untouched, it defaults
to DRM_MODE_DPMS_ON (0).

As a result, drm_helper_connector_dpms will exit when
it will be asked to set the state to DRM_MODE_DPMS_ON,
because it is already set.

That issue prevented displays from turning on at boot.
Signed-off-by: Denis Carikli <denis@eukrea.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/imx-drm/parallel-display.c

@@ -173,6 +173,13 @@ static int imx_pd_register(struct drm_device *drm,
 	if (ret)
 		return ret;
 
+	/* set the connector's dpms to OFF so that
+	 * drm_helper_connector_dpms() won't return
+	 * immediately since the current state is ON
+	 * at this point.
+	 */
+	imxpd->connector.dpms = DRM_MODE_DPMS_OFF;
+
 	drm_encoder_helper_add(&imxpd->encoder, &imx_pd_encoder_helper_funcs);
 	drm_encoder_init(drm, &imxpd->encoder, &imx_pd_encoder_funcs,
 			 DRM_MODE_ENCODER_NONE);