[PATCH RFC v2 17/18] drm/vkms: Introduce config for connector EDID

[Louis Chauvet <louis.chauvet@xxxxxxxxxxx>]

To properly test the EDID reading without using the DRM override, add an
option to configure the EDID for a connector.

Signed-off-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>
---
 drivers/gpu/drm/vkms/vkms_config.c |  1 +
 drivers/gpu/drm/vkms/vkms_config.h |  2 ++
 drivers/gpu/drm/vkms/vkms_output.c | 37 ++++++++++++++++++++++++++++++++++---
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index ac1a9658c5075c118d59da965ca3392355ccb2b2..1a1234d4f10fa8e5ea6bd649139ecc10c991f875 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -199,6 +199,7 @@ struct vkms_config_connector *vkms_config_create_connector(struct vkms_config *v
 	xa_init_flags(&vkms_config_connector->possible_encoders, XA_FLAGS_ALLOC);
 	vkms_config_connector->type = DRM_MODE_CONNECTOR_VIRTUAL;
 	vkms_config_connector->status = connector_status_unknown;
+	vkms_config_connector->edid_blob_len = 0;
 
 	return vkms_config_connector;
 }
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index bba56c9d8aeceac97a4339ef42ab663c5dc54e65..1220b16f6c98d1ebb0ae55d662a84fe25e1a6a02 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -112,6 +112,8 @@ struct vkms_config_connector {
 	struct xarray possible_encoders;
 	int type;
 	enum drm_connector_status status;
+	char edid_blob[PAGE_SIZE];
+	int edid_blob_len;
 
 	/* Internal usage */
 	struct drm_connector *connector;
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index fc6a0cdade0739b94820ed4e0924cf355137fe79..56590afb33d75465971d10a282040690840cdbee 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -31,13 +31,44 @@ static const struct drm_connector_funcs vkms_connector_funcs = {
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 };
 
+static int vkms_connector_read_block(void *context, u8 *buf, unsigned int block, size_t len)
+{
+	struct vkms_config_connector *config = context;
+
+	if (block * len + len > config->edid_blob_len)
+		return 1;
+	memcpy(buf, &config->edid_blob[block * len], len);
+	return 0;
+}
+
 static int vkms_conn_get_modes(struct drm_connector *connector)
 {
+	const struct drm_edid *drm_edid = NULL;
 	int count;
+	struct vkms_config_connector *connector_cfg;
+	struct vkms_device *vkmsdev = drm_device_to_vkms_device(connector->dev);
+	struct vkms_config_connector *context = NULL;
+
+	list_for_each_entry(connector_cfg, &vkmsdev->config->connectors, link) {
+		if (connector_cfg->connector == connector) {
+			context = connector_cfg;
+			break;
+		}
+	}
+	if (context)
+		drm_edid = drm_edid_read_custom(connector, vkms_connector_read_block, context);
+
+	/*
+	 * Unconditionally update the connector. If the EDID was read
+	 * successfully, fill in the connector information derived from the
+	 * EDID. Otherwise, if the EDID is NULL, clear the connector
+	 * information.
+	 */
+	drm_edid_connector_update(connector, drm_edid);
+
+	count = drm_edid_connector_add_modes(connector);
 
-	/* Use the default modes list from DRM */
-	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
-	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
+	drm_edid_free(drm_edid);
 
 	return count;
 }

-- 
2.47.0