[PATCH v2 1/3] drm/mediatek: mtk_dpi: Add check for max clock rate in mode_valid

[Jitao Shi]

Add per-platform max clock rate check in mtk_dpi_bridge_mode_valid.

Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_dpi.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index 52f11a63a330..ffa4a0f1989f 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -118,6 +118,7 @@ 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;
 };
 
@@ -555,9 +556,22 @@ 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_mode *mode)
+{
+	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
+
+	if (dpi->conf->max_clock_khz && 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,
 };
@@ -673,17 +687,20 @@ 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)
-- 
2.25.1