OMAP_VOUT: Remove manager->device references

With the introduction of output entities, managers will now connect to outputs.
Use the helper op for overlays named get_device. This will abstract away the
information on how to get the omap_dss_device pointer from an overlay.

Using the helper function will reduce the number of pointer dereferences a user
of OMAPDSS needs to do and reduce risk of a NULL dereference.

Cc: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Archit Taneja <archit@ti.com>

drivers/media/video/omap/omap_vout.c

@@ -454,11 +454,15 @@ static int omapvid_init(struct omap_vout_device *vout, u32 addr)
 
 	win = &vout->win;
 	for (i = 0; i < ovid->num_overlays; i++) {
+		struct omap_dss_device *dssdev;
+
 		ovl = ovid->overlays[i];
-		if (!ovl->manager || !ovl->manager->device)
+		dssdev = ovl->get_device(ovl);
+
+		if (!dssdev)
 			return -EINVAL;
 
-		timing = &ovl->manager->device->panel.timings;
+		timing = &dssdev->panel.timings;
 
 		outw = win->w.width;
 		outh = win->w.height;
@@ -515,8 +519,11 @@ static int omapvid_apply_changes(struct omap_vout_device *vout)
 	struct omapvideo_info *ovid = &vout->vid_info;
 
 	for (i = 0; i < ovid->num_overlays; i++) {
+		struct omap_dss_device *dssdev;
+
 		ovl = ovid->overlays[i];
-		if (!ovl->manager || !ovl->manager->device)
+		dssdev = ovl->get_device(ovl);
+		if (!dssdev)
 			return -EINVAL;
 		ovl->manager->apply(ovl->manager);
 	}
@@ -579,12 +586,14 @@ static void omap_vout_isr(void *arg, unsigned int irqstatus)
 
 	ovid = &vout->vid_info;
 	ovl = ovid->overlays[0];
-	/* get the display device attached to the overlay */
-	if (!ovl->manager || !ovl->manager->device)
-		return;
 
 	mgr_id = ovl->manager->id;
-	cur_display = ovl->manager->device;
+
+	/* get the display device attached to the overlay */
+	cur_display = ovl->get_device(ovl);
+
+	if (!cur_display)
+		return;
 
 	spin_lock(&vout->vbq_lock);
 	do_gettimeofday(&timevalue);
@@ -948,7 +957,9 @@ static int omap_vout_release(struct file *file)
 	/* Disable all the overlay managers connected with this interface */
 	for (i = 0; i < ovid->num_overlays; i++) {
 		struct omap_overlay *ovl = ovid->overlays[i];
-		if (ovl->manager && ovl->manager->device)
+		struct omap_dss_device *dssdev = ovl->get_device(ovl);
+
+		if (dssdev)
 			ovl->disable(ovl);
 	}
 	/* Turn off the pipeline */
@@ -1081,14 +1092,17 @@ static int vidioc_try_fmt_vid_out(struct file *file, void *fh,
 	struct omapvideo_info *ovid;
 	struct omap_video_timings *timing;
 	struct omap_vout_device *vout = fh;
+	struct omap_dss_device *dssdev;
 
 	ovid = &vout->vid_info;
 	ovl = ovid->overlays[0];
+	/* get the display device attached to the overlay */
+	dssdev = ovl->get_device(ovl);
 
-	if (!ovl->manager || !ovl->manager->device)
+	if (!dssdev)
 		return -EINVAL;
-	/* get the display device attached to the overlay */
-	timing = &ovl->manager->device->panel.timings;
+
+	timing = &dssdev->panel.timings;
 
 	vout->fbuf.fmt.height = timing->y_res;
 	vout->fbuf.fmt.width = timing->x_res;
@@ -1105,6 +1119,7 @@ static int vidioc_s_fmt_vid_out(struct file *file, void *fh,
 	struct omapvideo_info *ovid;
 	struct omap_video_timings *timing;
 	struct omap_vout_device *vout = fh;
+	struct omap_dss_device *dssdev;
 
 	if (vout->streaming)
 		return -EBUSY;
@@ -1113,13 +1128,14 @@ static int vidioc_s_fmt_vid_out(struct file *file, void *fh,
 
 	ovid = &vout->vid_info;
 	ovl = ovid->overlays[0];
+	dssdev = ovl->get_device(ovl);
 
 	/* get the display device attached to the overlay */
-	if (!ovl->manager || !ovl->manager->device) {
+	if (!dssdev) {
 		ret = -EINVAL;
 		goto s_fmt_vid_out_exit;
 	}
-	timing = &ovl->manager->device->panel.timings;
+	timing = &dssdev->panel.timings;
 
 	/* We dont support RGB24-packed mode if vrfb rotation
 	 * is enabled*/
@@ -1298,6 +1314,7 @@ static int vidioc_s_crop(struct file *file, void *fh, struct v4l2_crop *crop)
 	struct omapvideo_info *ovid;
 	struct omap_overlay *ovl;
 	struct omap_video_timings *timing;
+	struct omap_dss_device *dssdev;
 
 	if (vout->streaming)
 		return -EBUSY;
@@ -1305,13 +1322,15 @@ static int vidioc_s_crop(struct file *file, void *fh, struct v4l2_crop *crop)
 	mutex_lock(&vout->lock);
 	ovid = &vout->vid_info;
 	ovl = ovid->overlays[0];
+	/* get the display device attached to the overlay */
+	dssdev = ovl->get_device(ovl);
 
-	if (!ovl->manager || !ovl->manager->device) {
+	if (!dssdev) {
 		ret = -EINVAL;
 		goto s_crop_err;
 	}
-	/* get the display device attached to the overlay */
-	timing = &ovl->manager->device->panel.timings;
+
+	timing = &dssdev->panel.timings;
 
 	if (is_rotation_90_or_270(vout)) {
 		vout->fbuf.fmt.height = timing->x_res;
@@ -1667,7 +1686,7 @@ static int vidioc_streamon(struct file *file, void *fh, enum v4l2_buf_type i)
 	for (j = 0; j < ovid->num_overlays; j++) {
 		struct omap_overlay *ovl = ovid->overlays[j];
 
-		if (ovl->manager && ovl->manager->device) {
+		if (ovl->get_device(ovl)) {
 			struct omap_overlay_info info;
 			ovl->get_overlay_info(ovl, &info);
 			info.paddr = addr;
@@ -1690,8 +1709,9 @@ static int vidioc_streamon(struct file *file, void *fh, enum v4l2_buf_type i)
 
 	for (j = 0; j < ovid->num_overlays; j++) {
 		struct omap_overlay *ovl = ovid->overlays[j];
+		struct omap_dss_device *dssdev = ovl->get_device(ovl);
 
-		if (ovl->manager && ovl->manager->device) {
+		if (dssdev) {
 			ret = ovl->enable(ovl);
 			if (ret)
 				goto streamon_err1;
@@ -1726,8 +1746,9 @@ static int vidioc_streamoff(struct file *file, void *fh, enum v4l2_buf_type i)
 
 	for (j = 0; j < ovid->num_overlays; j++) {
 		struct omap_overlay *ovl = ovid->overlays[j];
+		struct omap_dss_device *dssdev = ovl->get_device(ovl);
 
-		if (ovl->manager && ovl->manager->device)
+		if (dssdev)
 			ovl->disable(ovl);
 	}
 
@@ -1890,8 +1911,8 @@ static int __init omap_vout_setup_video_data(struct omap_vout_device *vout)
 	struct video_device *vfd;
 	struct v4l2_pix_format *pix;
 	struct v4l2_control *control;
-	struct omap_dss_device *display =
-		vout->vid_info.overlays[0]->manager->device;
+	struct omap_overlay *ovl = vout->vid_info.overlays[0];
+	struct omap_dss_device *display = ovl->get_device(ovl);
 
 	/* set the default pix */
 	pix = &vout->pix;
@@ -2205,8 +2226,10 @@ static int __init omap_vout_probe(struct platform_device *pdev)
 	 */
 	for (i = 1; i < vid_dev->num_overlays; i++) {
 		ovl = omap_dss_get_overlay(i);
-		if (ovl->manager && ovl->manager->device) {
-			def_display = ovl->manager->device;
+		dssdev = ovl->get_device(ovl);
+
+		if (dssdev) {
+			def_display = dssdev;
 		} else {
 			dev_warn(&pdev->dev, "cannot find display\n");
 			def_display = NULL;
@@ -2253,8 +2276,10 @@ probe_err1:
 	for (i = 1; i < vid_dev->num_overlays; i++) {
 		def_display = NULL;
 		ovl = omap_dss_get_overlay(i);
-		if (ovl->manager && ovl->manager->device)
-			def_display = ovl->manager->device;
+		dssdev = ovl->get_device(ovl);
+
+		if (dssdev)
+			def_display = dssdev;
 
 		if (def_display && def_display->driver)
 			def_display->driver->disable(def_display);