[PATCH 8/8] drm: atmel-hlcdc: add LVDS output mode support

Manikandan Muralidharan manikandan.m at microchip.com
Tue May 19 02:01:35 PDT 2026


Introduce atmel_xlcdc_connector_output_lvds() to map LVDS bus
formats to the appropriate output mode, and wire it into
atmel_hlcdc_connector_output_mode() for LVDS encoder types.

Signed-off-by: Manikandan Muralidharan <manikandan.m at microchip.com>
---
 .../gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c    | 44 +++++++++++++++++--
 1 file changed, 41 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
index 73a8650bc9b7..9f46c368835e 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
@@ -407,6 +407,42 @@ static int atmel_xlcdc_connector_output_dsi(struct drm_encoder *encoder,
 	return supported_fmts;
 }
 
+static int atmel_xlcdc_connector_output_lvds(struct drm_encoder *encoder,
+					     struct drm_display_info *info)
+{
+	int j;
+	unsigned int supported_fmts = 0;
+
+	switch (atmel_hlcdc_encoder_get_bus_fmt(encoder)) {
+	case 0:
+		break;
+	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
+	case MEDIA_BUS_FMT_RGB666_1X18:
+		return ATMEL_HLCDC_RGB666_OUTPUT;
+	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
+	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
+		return ATMEL_HLCDC_RGB888_OUTPUT;
+	default:
+		return -EINVAL;
+	}
+
+	for (j = 0; j < info->num_bus_formats; j++) {
+		switch (info->bus_formats[j]) {
+		case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
+		case MEDIA_BUS_FMT_RGB666_1X18:
+			supported_fmts |= ATMEL_HLCDC_RGB666_OUTPUT;
+			break;
+		case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
+		case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
+			supported_fmts |= ATMEL_HLCDC_RGB888_OUTPUT;
+			break;
+		default:
+			break;
+		}
+	}
+	return supported_fmts;
+}
+
 static int atmel_hlcdc_connector_output_mode(struct drm_connector_state *state)
 {
 	struct drm_connector *connector = state->connector;
@@ -419,12 +455,14 @@ static int atmel_hlcdc_connector_output_mode(struct drm_connector_state *state)
 	if (!encoder)
 		encoder = connector->encoder;
 	/*
-	 * atmel-hlcdc to support DSI formats with DSI video pipeline
-	 * when DRM_MODE_ENCODER_DSI type is set by
-	 * connector driver component.
+	 * Select the output format based on the encoder type.
+	 * DSI and LVDS encoders have dedicated format handlers,
+	 * while other encoder types fall through to the generic path
 	 */
 	if (encoder->encoder_type == DRM_MODE_ENCODER_DSI)
 		return atmel_xlcdc_connector_output_dsi(encoder, info);
+	if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
+		return atmel_xlcdc_connector_output_lvds(encoder, info);
 
 	switch (atmel_hlcdc_encoder_get_bus_fmt(encoder)) {
 	case 0:
-- 
2.25.1




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