drm/mediatek: dpi: Add check for max clock rate in mode_valid

Add per-platform max clock rate check in mtk_dpi_bridge_mode_valid.
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drivers/gpu/drm/mediatek/mtk_dpi.c

@@ -120,6 +120,7 @@ struct mtk_dpi_yc_limit {
 struct mtk_dpi_conf {
 	unsigned int (*cal_factor)(int clock);
 	u32 reg_h_fre_con;
+	u32 max_clock_khz;
 	bool edge_sel_en;
 };
 
@@ -557,9 +558,23 @@ static void mtk_dpi_bridge_enable(struct drm_bridge *bridge)
 	mtk_dpi_set_display_mode(dpi, &dpi->mode);
 }
 
+static enum drm_mode_status
+mtk_dpi_bridge_mode_valid(struct drm_bridge *bridge,
+			  const struct drm_display_info *info,
+			  const struct drm_display_mode *mode)
+{
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
+
+	if (mode->clock > dpi->conf->max_clock_khz)
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
 static const struct drm_bridge_funcs mtk_dpi_bridge_funcs = {
 	.attach = mtk_dpi_bridge_attach,
 	.mode_set = mtk_dpi_bridge_mode_set,
+	.mode_valid = mtk_dpi_bridge_mode_valid,
 	.disable = mtk_dpi_bridge_disable,
 	.enable = mtk_dpi_bridge_enable,
 };
@@ -668,17 +683,20 @@ static unsigned int mt8183_calculate_factor(int clock)
 static const struct mtk_dpi_conf mt8173_conf = {
 	.cal_factor = mt8173_calculate_factor,
 	.reg_h_fre_con = 0xe0,
+	.max_clock_khz = 300000,
 };
 
 static const struct mtk_dpi_conf mt2701_conf = {
 	.cal_factor = mt2701_calculate_factor,
 	.reg_h_fre_con = 0xb0,
 	.edge_sel_en = true,
+	.max_clock_khz = 150000,
 };
 
 static const struct mtk_dpi_conf mt8183_conf = {
 	.cal_factor = mt8183_calculate_factor,
 	.reg_h_fre_con = 0xe0,
+	.max_clock_khz = 100000,
 };
 
 static int mtk_dpi_probe(struct platform_device *pdev)