The THC63LVD1024 is restricted to a pixel clock frequency in the range
of 8 to 135 MHz. Implement the bridge .mode_valid() operation
accordingly.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/thc63lvd1024.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/gpu/drm/bridge/thc63lvd1024.c b/drivers/gpu/drm/bridge/thc63lvd1024.c
index c8b9edd5a7f4..63609ba16b6d 100644
--- a/drivers/gpu/drm/bridge/thc63lvd1024.c
+++ b/drivers/gpu/drm/bridge/thc63lvd1024.c
@@ -45,6 +45,23 @@ static int thc63_attach(struct drm_bridge *bridge)
return drm_bridge_attach(bridge->encoder, thc63->next, bridge);
}
+static enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge,
+ const struct drm_display_mode *mode)
+{
+ /*
+ * The THC63LVD0124 clock frequency range is 8 to 135 MHz in single-in,
+ * single-out mode. Note that the limits depends on the mode and will
+ * need to be adjusted accordingly.
+ */
+ if (mode->clock < 8000)
+ return MODE_CLOCK_LOW;
+
+ if (mode->clock > 135000)
+ return MODE_CLOCK_HIGH;
+
+ return MODE_OK;
+}
+
static void thc63_enable(struct drm_bridge *bridge)
{
struct thc63_dev *thc63 = to_thc63(bridge);
@@ -77,6 +94,7 @@ static void thc63_disable(struct drm_bridge *bridge)
static const struct drm_bridge_funcs thc63_bridge_func = {
.attach = thc63_attach,
+ .mode_valid = thc63_mode_valid,
.enable = thc63_enable,
.disable = thc63_disable,
};
--
Regards,
Laurent Pinchart
