media: vimc: keep the error value when adding an entity fails

Currently when the 'add' callback of an entity fails, a
NULL is returned. This hides the error code of the failure
and always returns -EINVAL.

Replace return NULL with return ERR_PTR(ret) to improve debugging.
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/test_drivers/vimc/vimc-capture.c

@@ -395,7 +395,7 @@ struct vimc_ent_device *vimc_cap_add(struct vimc_device *vimc,
 	/* Allocate the vimc_cap_device struct */
 	vcap = kzalloc(sizeof(*vcap), GFP_KERNEL);
 	if (!vcap)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	/* Initialize the media entity */
 	vcap->vdev.entity.name = vcfg_name;
@@ -476,5 +476,5 @@ struct vimc_ent_device *vimc_cap_add(struct vimc_device *vimc,
 err_free_vcap:
 	kfree(vcap);
 
-	return NULL;
+	return ERR_PTR(ret);
 }

drivers/media/test_drivers/vimc/vimc-core.c

@@ -187,12 +187,15 @@ static int vimc_add_subdevs(struct vimc_device *vimc)
 			vimc->pipe_cfg->ents[i].name);
 		vimc->ent_devs[i] = vimc->pipe_cfg->ents[i].add(vimc,
 					vimc->pipe_cfg->ents[i].name);
-		if (!vimc->ent_devs[i]) {
-			dev_err(vimc->mdev.dev, "add new entity for %s\n",
-				vimc->pipe_cfg->ents[i].name);
+		if (IS_ERR(vimc->ent_devs[i])) {
+			int err = PTR_ERR(vimc->ent_devs[i]);
+
+			dev_err(vimc->mdev.dev, "adding entity %s failed (%d)\n",
+				vimc->pipe_cfg->ents[i].name, err);
+			vimc->ent_devs[i] = NULL;
 			vimc_unregister_subdevs(vimc);
 			vimc_release_subdevs(vimc);
-			return -EINVAL;
+			return err;
 		}
 	}
 	return 0;

drivers/media/test_drivers/vimc/vimc-debayer.c

@@ -532,7 +532,7 @@ struct vimc_ent_device *vimc_deb_add(struct vimc_device *vimc,
 	/* Allocate the vdeb struct */
 	vdeb = kzalloc(sizeof(*vdeb), GFP_KERNEL);
 	if (!vdeb)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	/* Create controls: */
 	v4l2_ctrl_handler_init(&vdeb->hdl, 2);
@@ -577,5 +577,5 @@ struct vimc_ent_device *vimc_deb_add(struct vimc_device *vimc,
 err_free_vdeb:
 	kfree(vdeb);
 
-	return NULL;
+	return ERR_PTR(ret);
 }

drivers/media/test_drivers/vimc/vimc-scaler.c

@@ -483,7 +483,7 @@ struct vimc_ent_device *vimc_sca_add(struct vimc_device *vimc,
 	/* Allocate the vsca struct */
 	vsca = kzalloc(sizeof(*vsca), GFP_KERNEL);
 	if (!vsca)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	/* Initialize ved and sd */
 	vsca->pads[0].flags = MEDIA_PAD_FL_SINK;
@@ -495,7 +495,7 @@ struct vimc_ent_device *vimc_sca_add(struct vimc_device *vimc,
 				   vsca->pads, &vimc_sca_ops);
 	if (ret) {
 		kfree(vsca);
-		return NULL;
+		return ERR_PTR(ret);
 	}
 
 	vsca->ved.process_frame = vimc_sca_process_frame;

drivers/media/test_drivers/vimc/vimc-sensor.c

@@ -317,7 +317,7 @@ struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
 	/* Allocate the vsen struct */
 	vsen = kzalloc(sizeof(*vsen), GFP_KERNEL);
 	if (!vsen)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	v4l2_ctrl_handler_init(&vsen->hdl, 4);
 
@@ -372,5 +372,5 @@ struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
 err_free_vsen:
 	kfree(vsen);
 
-	return NULL;
+	return ERR_PTR(ret);
 }