Implement a .mode_valid() handler in the R-Car glue layer to reject
modes with an unsupported clock frequency.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
Changes since v1:
- Add a comment to explain where the limit comes from
diff --git a/drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c b/drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c
index 75490a3e0a2a..603bb340e8cf 100644
--- a/drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c
+++ b/drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c
@@ -35,6 +35,20 @@ static const struct rcar_hdmi_phy_params rcar_hdmi_phy_params[] = {
{ ~0UL, 0x0000, 0x0000, 0x0000 },
};
+static enum drm_mode_status
+rcar_hdmi_mode_valid(struct drm_connector *connector,
+ const struct drm_display_mode *mode)
+{
+ /*
+ * The maximum supported clock frequency is 297 MHz, as shown in the PHY
+ * parameters table.
+ */
+ if (mode->clock > 297000)
+ return MODE_CLOCK_HIGH;
+
+ return MODE_OK;
+}
+
static int rcar_hdmi_phy_configure(struct dw_hdmi *hdmi,
const struct dw_hdmi_plat_data *pdata,
unsigned long mpixelclock)
@@ -59,6 +73,7 @@ static int rcar_hdmi_phy_configure(struct dw_hdmi *hdmi,
}
static const struct dw_hdmi_plat_data rcar_dw_hdmi_plat_data = {
+ .mode_valid = rcar_hdmi_mode_valid,
.configure_phy = rcar_hdmi_phy_configure,
};
--
Regards,
Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
