drm/mediatek: mtk_hdmi: Improve mtk_hdmi_get_all_clk() flexibility

In preparation for splitting common bits of this driver and for
introducing a new version of the MediaTek HDMI Encoder IP, improve
the flexibility	of function mtk_hdmi_get_all_clk() by adding a
pointer to the clock names array and size of it to its parameters.

Also change the array of struct clock pointers in the mtk_hdmi
structure to be dynamically allocated, and allocate it in probe.

Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Louis-Alexis Eyraud <louisalexis.eyraud@collabora.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20251023-mediatek-drm-hdmi-v2-v11-2-7873ec4a1edf@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

Author: AngeloGioacchino Del Regno

drivers/gpu/drm/mediatek/mtk_hdmi.c

@@ -159,7 +159,7 @@ struct mtk_hdmi {
 	struct phy *phy;
 	struct device *cec_dev;
 	struct i2c_adapter *ddc_adpt;
-	struct clk *clk[MTK_HDMI_CLK_COUNT];
+	struct clk **clk;
 	struct drm_display_mode mode;
 	bool dvi_mode;
 	struct regmap *sys_regmap;
@@ -1072,17 +1072,18 @@ static const char * const mtk_hdmi_clk_names[MTK_HDMI_CLK_COUNT] = {
 	[MTK_HDMI_CLK_AUD_SPDIF] = "spdif",
 };
 
-static int mtk_hdmi_get_all_clk(struct mtk_hdmi *hdmi,
-				struct device_node *np)
+static int mtk_hdmi_get_all_clk(struct mtk_hdmi *hdmi, struct device_node *np,
+				const char * const *clock_names, size_t num_clocks)
 {
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(mtk_hdmi_clk_names); i++) {
-		hdmi->clk[i] = of_clk_get_by_name(np,
-						  mtk_hdmi_clk_names[i]);
+	for (i = 0; i < num_clocks; i++) {
+		hdmi->clk[i] = of_clk_get_by_name(np, clock_names[i]);
+
 		if (IS_ERR(hdmi->clk[i]))
 			return PTR_ERR(hdmi->clk[i]);
 	}
+
 	return 0;
 }
 
@@ -1391,15 +1392,15 @@ static int mtk_hdmi_get_cec_dev(struct mtk_hdmi *hdmi, struct device *dev, struc
 	return 0;
 }
 
-static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
-				   struct platform_device *pdev)
+static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi, struct platform_device *pdev,
+				   const char * const *clk_names, size_t num_clocks)
 {
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	struct device_node *remote, *i2c_np;
 	int ret;
 
-	ret = mtk_hdmi_get_all_clk(hdmi, np);
+	ret = mtk_hdmi_get_all_clk(hdmi, np, clk_names, num_clocks);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to get clocks\n");
 
@@ -1652,6 +1653,7 @@ static int mtk_hdmi_probe(struct platform_device *pdev)
 {
 	struct mtk_hdmi *hdmi;
 	struct device *dev = &pdev->dev;
+	const int num_clocks = MTK_HDMI_CLK_COUNT;
 	int ret;
 
 	hdmi = devm_drm_bridge_alloc(dev, struct mtk_hdmi, bridge,
@@ -1662,7 +1664,11 @@ static int mtk_hdmi_probe(struct platform_device *pdev)
 	hdmi->dev = dev;
 	hdmi->conf = of_device_get_match_data(dev);
 
-	ret = mtk_hdmi_dt_parse_pdata(hdmi, pdev);
+	hdmi->clk = devm_kcalloc(dev, num_clocks, sizeof(*hdmi->clk), GFP_KERNEL);
+	if (!hdmi->clk)
+		return -ENOMEM;
+
+	ret = mtk_hdmi_dt_parse_pdata(hdmi, pdev, mtk_hdmi_clk_names, num_clocks);
 	if (ret)
 		return ret;