media: mtk-vcodec: Get numbers of register bases from DT

Different platforms may have different numbers of register bases. Gets the
numbers of register bases from dts (sizeof(u32) * 4 bytes for each).
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c

@@ -75,6 +75,30 @@ static irqreturn_t mtk_vcodec_dec_irq_handler(int irq, void *priv)
 	return IRQ_HANDLED;
 }
 
+static int mtk_vcodec_get_reg_bases(struct mtk_vcodec_dev *dev)
+{
+	struct platform_device *pdev = dev->plat_dev;
+	int reg_num, i;
+
+	/* Sizeof(u32) * 4 bytes for each register base. */
+	reg_num = of_property_count_elems_of_size(pdev->dev.of_node, "reg",
+						  sizeof(u32) * 4);
+	if (reg_num <= 0 || reg_num > NUM_MAX_VDEC_REG_BASE) {
+		dev_err(&pdev->dev, "Invalid register property size: %d\n", reg_num);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < reg_num; i++) {
+		dev->reg_base[i] = devm_platform_ioremap_resource(pdev, i);
+		if (IS_ERR(dev->reg_base[i]))
+			return PTR_ERR(dev->reg_base[i]);
+
+		mtk_v4l2_debug(2, "reg[%d] base=%p", i, dev->reg_base[i]);
+	}
+
+	return 0;
+}
+
 static int fops_vcodec_open(struct file *file)
 {
 	struct mtk_vcodec_dev *dev = video_drvdata(file);
@@ -203,7 +227,7 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
 	struct resource *res;
 	phandle rproc_phandle;
 	enum mtk_vcodec_fw_type fw_type;
-	int i, ret;
+	int ret;
 
 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 	if (!dev)
@@ -235,14 +259,9 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
 		goto err_dec_pm;
 	}
 
-	for (i = 0; i < NUM_MAX_VDEC_REG_BASE; i++) {
-		dev->reg_base[i] = devm_platform_ioremap_resource(pdev, i);
-		if (IS_ERR((__force void *)dev->reg_base[i])) {
-			ret = PTR_ERR((__force void *)dev->reg_base[i]);
-			goto err_res;
-		}
-		mtk_v4l2_debug(2, "reg[%d] base=%p", i, dev->reg_base[i]);
-	}
+	ret = mtk_vcodec_get_reg_bases(dev);
+	if (ret)
+		goto err_res;
 
 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (res == NULL) {