drm/vc4: Add monochrome mode to the VEC.

The VEC supports not producing colour bursts for monochrome output.
It also has an option for disabling the chroma input to remove
chroma from the signal.

Now that there is a DRM_MODE_TV_MODE_MONOCHROME defined, plumb
this in.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240619153913.2804051-3-dave.stevenson@raspberrypi.com

drivers/gpu/drm/vc4/vc4_vec.c

@@ -234,6 +234,7 @@ enum vc4_vec_tv_mode_id {
 	VC4_VEC_TV_MODE_PAL_60,
 	VC4_VEC_TV_MODE_PAL_N,
 	VC4_VEC_TV_MODE_SECAM,
+	VC4_VEC_TV_MODE_MONOCHROME,
 };
 
 struct vc4_vec_tv_mode {
@@ -324,6 +325,22 @@ static const struct vc4_vec_tv_mode vc4_vec_tv_modes[] = {
 		.config1 = VEC_CONFIG1_C_CVBS_CVBS,
 		.custom_freq = 0x29c71c72,
 	},
+	{
+		/* 50Hz mono */
+		.mode = DRM_MODE_TV_MODE_MONOCHROME,
+		.expected_htotal = 864,
+		.config0 = VEC_CONFIG0_PAL_BDGHI_STD | VEC_CONFIG0_BURDIS |
+			   VEC_CONFIG0_CHRDIS,
+		.config1 = VEC_CONFIG1_C_CVBS_CVBS,
+	},
+	{
+		/* 60Hz mono */
+		.mode = DRM_MODE_TV_MODE_MONOCHROME,
+		.expected_htotal = 858,
+		.config0 = VEC_CONFIG0_PAL_M_STD | VEC_CONFIG0_BURDIS |
+			   VEC_CONFIG0_CHRDIS,
+		.config1 = VEC_CONFIG1_C_CVBS_CVBS,
+	},
 };
 
 static inline const struct vc4_vec_tv_mode *
@@ -351,6 +368,7 @@ static const struct drm_prop_enum_list legacy_tv_mode_names[] = {
 	{ VC4_VEC_TV_MODE_PAL_M, "PAL-M", },
 	{ VC4_VEC_TV_MODE_PAL_N, "PAL-N", },
 	{ VC4_VEC_TV_MODE_SECAM, "SECAM", },
+	{ VC4_VEC_TV_MODE_MONOCHROME, "Mono", },
 };
 
 static enum drm_connector_status
@@ -406,6 +424,10 @@ vc4_vec_connector_set_property(struct drm_connector *connector,
 		state->tv.mode = DRM_MODE_TV_MODE_SECAM;
 		break;
 
+	case VC4_VEC_TV_MODE_MONOCHROME:
+		state->tv.mode = DRM_MODE_TV_MODE_MONOCHROME;
+		break;
+
 	default:
 		return -EINVAL;
 	}
@@ -453,6 +475,10 @@ vc4_vec_connector_get_property(struct drm_connector *connector,
 		*val = VC4_VEC_TV_MODE_SECAM;
 		break;
 
+	case DRM_MODE_TV_MODE_MONOCHROME:
+		*val = VC4_VEC_TV_MODE_MONOCHROME;
+		break;
+
 	default:
 		return -EINVAL;
 	}
@@ -754,7 +780,8 @@ static int vc4_vec_bind(struct device *dev, struct device *master, void *data)
 					    BIT(DRM_MODE_TV_MODE_PAL) |
 					    BIT(DRM_MODE_TV_MODE_PAL_M) |
 					    BIT(DRM_MODE_TV_MODE_PAL_N) |
-					    BIT(DRM_MODE_TV_MODE_SECAM));
+					    BIT(DRM_MODE_TV_MODE_SECAM) |
+					    BIT(DRM_MODE_TV_MODE_MONOCHROME));
 	if (ret)
 		return ret;