Revert "drm/omap: dss: Remove unused omap_dss_device operations"

This reverts commit e086558ae9 ("drm/omap: dss: Remove unused
omap_dss_device operations")

This is still needed by DSI. E.g. unloading modules without this will
cause a crash.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215104657.802264-2-tomi.valkeinen@ti.com

drivers/gpu/drm/omapdrm/dss/base.c

@@ -234,6 +234,18 @@ void omapdss_device_disconnect(struct omap_dss_device *src,
 }
 EXPORT_SYMBOL_GPL(omapdss_device_disconnect);
 
+void omapdss_device_pre_enable(struct omap_dss_device *dssdev)
+{
+	if (!dssdev)
+		return;
+
+	omapdss_device_pre_enable(dssdev->next);
+
+	if (dssdev->ops && dssdev->ops->pre_enable)
+		dssdev->ops->pre_enable(dssdev);
+}
+EXPORT_SYMBOL_GPL(omapdss_device_pre_enable);
+
 void omapdss_device_enable(struct omap_dss_device *dssdev)
 {
 	if (!dssdev)
@@ -260,6 +272,20 @@ void omapdss_device_disable(struct omap_dss_device *dssdev)
 }
 EXPORT_SYMBOL_GPL(omapdss_device_disable);
 
+void omapdss_device_post_disable(struct omap_dss_device *dssdev)
+{
+	if (!dssdev)
+		return;
+
+	if (dssdev->ops && dssdev->ops->post_disable)
+		dssdev->ops->post_disable(dssdev);
+
+	omapdss_device_post_disable(dssdev->next);
+
+	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
+}
+EXPORT_SYMBOL_GPL(omapdss_device_post_disable);
+
 /* -----------------------------------------------------------------------------
  * Components Handling
  */

drivers/gpu/drm/omapdrm/dss/omapdss.h

@@ -346,11 +346,15 @@ struct omap_dss_device_ops {
 	void (*disconnect)(struct omap_dss_device *dssdev,
 			struct omap_dss_device *dst);
 
+	void (*pre_enable)(struct omap_dss_device *dssdev);
 	void (*enable)(struct omap_dss_device *dssdev);
 	void (*disable)(struct omap_dss_device *dssdev);
+	void (*post_disable)(struct omap_dss_device *dssdev);
 
 	int (*check_timings)(struct omap_dss_device *dssdev,
 			     struct drm_display_mode *mode);
+	void (*set_timings)(struct omap_dss_device *dssdev,
+			    const struct drm_display_mode *mode);
 
 	int (*get_modes)(struct omap_dss_device *dssdev,
 			 struct drm_connector *connector);
@@ -449,8 +453,10 @@ int omapdss_device_connect(struct dss_device *dss,
 			   struct omap_dss_device *dst);
 void omapdss_device_disconnect(struct omap_dss_device *src,
 			       struct omap_dss_device *dst);
+void omapdss_device_pre_enable(struct omap_dss_device *dssdev);
 void omapdss_device_enable(struct omap_dss_device *dssdev);
 void omapdss_device_disable(struct omap_dss_device *dssdev);
+void omapdss_device_post_disable(struct omap_dss_device *dssdev);
 
 int omap_dss_get_num_overlay_managers(void);
 

drivers/gpu/drm/omapdrm/omap_encoder.c

@@ -113,8 +113,13 @@ static void omap_encoder_mode_set(struct drm_encoder *encoder,
 	bus_flags = connector->display_info.bus_flags;
 	omap_encoder_update_videomode_flags(&vm, bus_flags);
 
-	/* Set timings for the dss manager. */
+	/* Set timings for all devices in the display pipeline. */
 	dss_mgr_set_timings(output, &vm);
+
+	for (dssdev = output; dssdev; dssdev = dssdev->next) {
+		if (dssdev->ops && dssdev->ops->set_timings)
+			dssdev->ops->set_timings(dssdev, adjusted_mode);
+	}
 }
 
 static void omap_encoder_disable(struct drm_encoder *encoder)
@@ -127,10 +132,26 @@ static void omap_encoder_disable(struct drm_encoder *encoder)
 
 	/*
 	 * Disable the chain of external devices, starting at the one at the
-	 * internal encoder's output. This is used for DSI outputs only, as
+	 * internal encoder's output.
-	 * dssdev->next is NULL for all other outputs.
 	 */
 	omapdss_device_disable(dssdev->next);
+
+	/*
+	 * Disable the internal encoder. This will disable the DSS output. The
+	 * DSI is treated as an exception as DSI pipelines still use the legacy
+	 * flow where the pipeline output controls the encoder.
+	 */
+	if (dssdev->type != OMAP_DISPLAY_TYPE_DSI) {
+		if (dssdev->ops && dssdev->ops->disable)
+			dssdev->ops->disable(dssdev);
+		dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
+	}
+
+	/*
+	 * Perform the post-disable operations on the chain of external devices
+	 * to complete the display pipeline disable.
+	 */
+	omapdss_device_post_disable(dssdev->next);
 }
 
 static void omap_encoder_enable(struct drm_encoder *encoder)
@@ -141,10 +162,23 @@ static void omap_encoder_enable(struct drm_encoder *encoder)
 
 	dev_dbg(dev->dev, "enable(%s)\n", dssdev->name);
 
+	/* Prepare the chain of external devices for pipeline enable. */
+	omapdss_device_pre_enable(dssdev->next);
+
+	/*
+	 * Enable the internal encoder. This will enable the DSS output. The
+	 * DSI is treated as an exception as DSI pipelines still use the legacy
+	 * flow where the pipeline output controls the encoder.
+	 */
+	if (dssdev->type != OMAP_DISPLAY_TYPE_DSI) {
+		if (dssdev->ops && dssdev->ops->enable)
+			dssdev->ops->enable(dssdev);
+		dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
+	}
+
 	/*
 	 * Enable the chain of external devices, starting at the one at the
-	 * internal encoder's output. This is used for DSI outputs only, as
+	 * internal encoder's output.
-	 * dssdev->next is NULL for all other outputs.
 	 */
 	omapdss_device_enable(dssdev->next);
 }