From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

The VCLK range for Renesas RZ/G2L SoC is 148.5 MHz to 5.803 MHz. Add a
minimum clock check in the mode_valid callback to ensure that the clock
value does not fall below the valid range.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index fa7a1ae22aa3..c6f60b7f203b 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -585,6 +585,9 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
 	if (mode->clock > 148500)
 		return MODE_CLOCK_HIGH;
 
+	if (mode->clock < 5803)
+		return MODE_CLOCK_LOW;
+
 	return MODE_OK;
 }
 
-- 
2.49.0