media: mtk-mdp: convert mtk_mdp_dev.comp array to list

The functions mtk_mdp_register/unregister_component have been created to
add / remove items from the list of components.

This will eventually enable us to specify a list of components in the
device tree instead of hardcoding them into this driver.

The list is modified by a single thread at driver probe time, and will
not be traversed by another thread until the call to pm_runtime_enable
at the end of probing.
Signed-off-by: Eizan Miyamoto <eizan@chromium.org>
Reviewed-by: Enric Balletbo I Serra <enric.balletbo@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/mtk-mdp/mtk_mdp_comp.c

@@ -103,6 +103,7 @@ int mtk_mdp_comp_init(struct device *dev, struct device_node *node,
 		return -EINVAL;
 	}
 
+	INIT_LIST_HEAD(&comp->node);
 	comp->dev_node = of_node_get(node);
 	comp->id = comp_id;
 	comp->type = mtk_mdp_matches[comp_id].type;

drivers/media/platform/mtk-mdp/mtk_mdp_comp.h

@@ -36,6 +36,7 @@ enum mtk_mdp_comp_id {
 
 /**
  * struct mtk_mdp_comp - the MDP's function component data
+ * @node:	list node to track sibing MDP components
  * @dev_node:	component device node
  * @clk:	clocks required for component
  * @larb_dev:	SMI device required for component
@@ -43,6 +44,7 @@ enum mtk_mdp_comp_id {
  * @id:		component ID
  */
 struct mtk_mdp_comp {
+	struct list_head	node;
 	struct device_node	*dev_node;
 	struct clk		*clk[2];
 	struct device		*larb_dev;

drivers/media/platform/mtk-mdp/mtk_mdp_core.c

@@ -55,19 +55,19 @@ MODULE_DEVICE_TABLE(of, mtk_mdp_of_ids);
 static void mtk_mdp_clock_on(struct mtk_mdp_dev *mdp)
 {
 	struct device *dev = &mdp->pdev->dev;
-	int i;
+	struct mtk_mdp_comp *comp_node;
 
-	for (i = 0; i < ARRAY_SIZE(mdp->comp); i++)
-		mtk_mdp_comp_clock_on(dev, mdp->comp[i]);
+	list_for_each_entry(comp_node, &mdp->comp_list, node)
+		mtk_mdp_comp_clock_on(dev, comp_node);
 }
 
 static void mtk_mdp_clock_off(struct mtk_mdp_dev *mdp)
 {
 	struct device *dev = &mdp->pdev->dev;
-	int i;
+	struct mtk_mdp_comp *comp_node;
 
-	for (i = 0; i < ARRAY_SIZE(mdp->comp); i++)
-		mtk_mdp_comp_clock_off(dev, mdp->comp[i]);
+	list_for_each_entry(comp_node, &mdp->comp_list, node)
+		mtk_mdp_comp_clock_off(dev, comp_node);
 }
 
 static void mtk_mdp_wdt_worker(struct work_struct *work)
@@ -91,12 +91,25 @@ static void mtk_mdp_reset_handler(void *priv)
 	queue_work(mdp->wdt_wq, &mdp->wdt_work);
 }
 
+void mtk_mdp_register_component(struct mtk_mdp_dev *mdp,
+				struct mtk_mdp_comp *comp)
+{
+	list_add(&mdp->comp_list, &comp->node);
+}
+
+void mtk_mdp_unregister_component(struct mtk_mdp_dev *mdp,
+				  struct mtk_mdp_comp *comp)
+{
+	list_del(&comp->node);
+}
+
 static int mtk_mdp_probe(struct platform_device *pdev)
 {
 	struct mtk_mdp_dev *mdp;
 	struct device *dev = &pdev->dev;
 	struct device_node *node, *parent;
-	int i, ret = 0;
+	struct mtk_mdp_comp *comp, *comp_temp;
+	int ret = 0;
 
 	mdp = devm_kzalloc(dev, sizeof(*mdp), GFP_KERNEL);
 	if (!mdp)
@@ -104,6 +117,7 @@ static int mtk_mdp_probe(struct platform_device *pdev)
 
 	mdp->id = pdev->id;
 	mdp->pdev = pdev;
+	INIT_LIST_HEAD(&mdp->comp_list);
 	INIT_LIST_HEAD(&mdp->ctx_list);
 
 	mutex_init(&mdp->lock);
@@ -124,7 +138,6 @@ static int mtk_mdp_probe(struct platform_device *pdev)
 		const struct of_device_id *of_id;
 		enum mtk_mdp_comp_type comp_type;
 		int comp_id;
-		struct mtk_mdp_comp *comp;
 
 		of_id = of_match_node(mtk_mdp_comp_dt_ids, node);
 		if (!of_id)
@@ -150,13 +163,14 @@ static int mtk_mdp_probe(struct platform_device *pdev)
 			of_node_put(node);
 			goto err_comp;
 		}
-		mdp->comp[comp_id] = comp;
 
 		ret = mtk_mdp_comp_init(dev, node, comp, comp_id);
 		if (ret) {
 			of_node_put(node);
 			goto err_comp;
 		}
+
+		mtk_mdp_register_component(mdp, comp);
 	}
 
 	mdp->job_wq = create_singlethread_workqueue(MTK_MDP_MODULE_NAME);
@@ -220,8 +234,10 @@ static int mtk_mdp_probe(struct platform_device *pdev)
 err_alloc_job_wq:
 
 err_comp:
-	for (i = 0; i < ARRAY_SIZE(mdp->comp); i++)
-		mtk_mdp_comp_deinit(dev, mdp->comp[i]);
+	list_for_each_entry_safe(comp, comp_temp, &mdp->comp_list, node) {
+		mtk_mdp_unregister_component(mdp, comp);
+		mtk_mdp_comp_deinit(dev, comp);
+	}
 
 	dev_dbg(dev, "err %d\n", ret);
 	return ret;
@@ -230,7 +246,7 @@ static int mtk_mdp_probe(struct platform_device *pdev)
 static int mtk_mdp_remove(struct platform_device *pdev)
 {
 	struct mtk_mdp_dev *mdp = platform_get_drvdata(pdev);
-	int i;
+	struct mtk_mdp_comp *comp, *comp_temp;
 
 	pm_runtime_disable(&pdev->dev);
 	vb2_dma_contig_clear_max_seg_size(&pdev->dev);
@@ -243,8 +259,10 @@ static int mtk_mdp_remove(struct platform_device *pdev)
 	flush_workqueue(mdp->job_wq);
 	destroy_workqueue(mdp->job_wq);
 
-	for (i = 0; i < ARRAY_SIZE(mdp->comp); i++)
-		mtk_mdp_comp_deinit(&pdev->dev, mdp->comp[i]);
+	list_for_each_entry_safe(comp, comp_temp, &mdp->comp_list, node) {
+		mtk_mdp_unregister_component(mdp, comp);
+		mtk_mdp_comp_deinit(&pdev->dev, comp);
+	}
 
 	dev_dbg(&pdev->dev, "%s driver unloaded\n", pdev->name);
 	return 0;

drivers/media/platform/mtk-mdp/mtk_mdp_core.h

@@ -136,7 +136,7 @@ struct mtk_mdp_variant {
  * @pdev:	pointer to the image processor platform device
  * @variant:	the IP variant information
  * @id:		image processor device index (0..MTK_MDP_MAX_DEVS)
- * @comp:	MDP function components
+ * @comp_list:	list of MDP function components
  * @m2m_dev:	v4l2 memory-to-memory device data
  * @ctx_list:	list of struct mtk_mdp_ctx
  * @vdev:	video device for image processor driver
@@ -154,7 +154,7 @@ struct mtk_mdp_dev {
 	struct platform_device		*pdev;
 	struct mtk_mdp_variant		*variant;
 	u16				id;
-	struct mtk_mdp_comp		*comp[MTK_MDP_COMP_ID_MAX];
+	struct list_head		comp_list;
 	struct v4l2_m2m_dev		*m2m_dev;
 	struct list_head		ctx_list;
 	struct video_device		*vdev;
@@ -221,6 +221,12 @@ struct mtk_mdp_ctx {
 
 extern int mtk_mdp_dbg_level;
 
+void mtk_mdp_register_component(struct mtk_mdp_dev *mdp,
+				struct mtk_mdp_comp *comp);
+
+void mtk_mdp_unregister_component(struct mtk_mdp_dev *mdp,
+				  struct mtk_mdp_comp *comp);
+
 #if defined(DEBUG)
 
 #define mtk_mdp_dbg(level, fmt, args...)				 \