[RFC PATCH 1/4] drm/writeback: Add function that takes preallocated connector

[Suraj Kandpal <suraj.kandpal@intel.com>]

Write a function that takes a preallocated drm_connector instead of
using the one allocated inside the drm writeback connector init
function.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>

diff --git a/drivers/gpu/drm/drm_writeback.c b/drivers/gpu/drm/drm_writeback.c
index edbeab88ff2b..0d287ab9bded 100644
--- a/drivers/gpu/drm/drm_writeback.c
+++ b/drivers/gpu/drm/drm_writeback.c
@@ -414,6 +414,89 @@ int drmm_writeback_connector_init(struct drm_device *dev,
 }
 EXPORT_SYMBOL(drmm_writeback_connector_init);
 
+/*
+ * drm_writeback_connector_init_with_conn - Initialize a writeback connector with
+ * custom encoder and connector
+ *
+ * @enc: handle to the already initialized drm encoder
+ * @con_funcs: Connector funcs vtable
+ * @formats: Array of supported pixel formats for the writeback engine
+ * @n_formats: Length of the formats array
+ *
+ * This function assumes that the drm_writeback_connector's encoder has already been
+ * created and initialized before invoking this function.
+ *
+ * In addition, this function also assumes that callers of this API will manage
+ * assigning the encoder helper functions, possible_crtcs and any other encoder
+ * specific operation.
+ *
+ * Drivers should always use this function instead of drm_connector_init() to
+ * set up writeback connectors if they want to manage themselves the lifetime of the
+ * associated encoder.
+ *
+ * Returns: 0 on success, or a negative error code
+ */
+int
+drm_writeback_connector_init_with_conn(struct drm_device *dev, struct drm_connector *connector,
+				       struct drm_writeback_connector *wb_connector,
+				       struct drm_encoder *enc,
+				       const struct drm_connector_funcs *con_funcs,
+				       const u32 *formats, int n_formats)
+{
+	struct drm_property_blob *blob;
+	struct drm_mode_config *config = &dev->mode_config;
+	int ret = create_writeback_properties(dev);
+
+	if (ret != 0)
+		return ret;
+
+	blob = drm_property_create_blob(dev, n_formats * sizeof(*formats),
+					formats);
+	if (IS_ERR(blob))
+		return PTR_ERR(blob);
+
+
+	connector->interlace_allowed = 0;
+
+	ret = drm_connector_init(dev, connector, con_funcs,
+				 DRM_MODE_CONNECTOR_WRITEBACK);
+	if (ret)
+		goto connector_fail;
+
+	ret = drm_connector_attach_encoder(connector, enc);
+	if (ret)
+		goto attach_fail;
+
+	INIT_LIST_HEAD(&wb_connector->job_queue);
+	spin_lock_init(&wb_connector->job_lock);
+
+	wb_connector->fence_context = dma_fence_context_alloc(1);
+	spin_lock_init(&wb_connector->fence_lock);
+	snprintf(wb_connector->timeline_name,
+		 sizeof(wb_connector->timeline_name),
+		 "CONNECTOR:%d-%s", connector->base.id, connector->name);
+
+	drm_object_attach_property(&connector->base,
+				   config->writeback_out_fence_ptr_property, 0);
+
+	drm_object_attach_property(&connector->base,
+				   config->writeback_fb_id_property, 0);
+
+	drm_object_attach_property(&connector->base,
+				   config->writeback_pixel_formats_property,
+				   blob->base.id);
+	wb_connector->pixel_formats_blob_ptr = blob;
+
+	return 0;
+
+attach_fail:
+	drm_connector_cleanup(connector);
+connector_fail:
+	drm_property_blob_put(blob);
+	return ret;
+}
+EXPORT_SYMBOL(drm_writeback_connector_init_with_conn);
+
 int drm_writeback_set_fb(struct drm_connector_state *conn_state,
 			 struct drm_framebuffer *fb)
 {
diff --git a/include/drm/drm_writeback.h b/include/drm/drm_writeback.h
index c380a7b8f55a..149744dbeef0 100644
--- a/include/drm/drm_writeback.h
+++ b/include/drm/drm_writeback.h
@@ -167,6 +167,13 @@ int drmm_writeback_connector_init(struct drm_device *dev,
 				  struct drm_encoder *enc,
 				  const u32 *formats, int n_formats);
 
+int
+drm_writeback_connector_init_with_conn(struct drm_device *dev, struct drm_connector *connector,
+				       struct drm_writeback_connector *wb_connector,
+				       struct drm_encoder *enc,
+				       const struct drm_connector_funcs *con_funcs,
+				       const u32 *formats, int n_formats);
+
 int drm_writeback_set_fb(struct drm_connector_state *conn_state,
 			 struct drm_framebuffer *fb);
 
-- 
2.34.1