v4.19.13 snapshot.
diff --git a/include/drm/drm_writeback.h b/include/drm/drm_writeback.h
new file mode 100644
index 0000000..23df9d4
--- /dev/null
+++ b/include/drm/drm_writeback.h
@@ -0,0 +1,136 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) COPYRIGHT 2016 ARM Limited. All rights reserved.
+ * Author: Brian Starkey <brian.starkey@arm.com>
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ */
+
+#ifndef __DRM_WRITEBACK_H__
+#define __DRM_WRITEBACK_H__
+#include <drm/drm_connector.h>
+#include <drm/drm_encoder.h>
+#include <linux/workqueue.h>
+
+struct drm_writeback_connector {
+ struct drm_connector base;
+
+ /**
+ * @encoder: Internal encoder used by the connector to fulfill
+ * the DRM framework requirements. The users of the
+ * @drm_writeback_connector control the behaviour of the @encoder
+ * by passing the @enc_funcs parameter to drm_writeback_connector_init()
+ * function.
+ */
+ struct drm_encoder encoder;
+
+ /**
+ * @pixel_formats_blob_ptr:
+ *
+ * DRM blob property data for the pixel formats list on writeback
+ * connectors
+ * See also drm_writeback_connector_init()
+ */
+ struct drm_property_blob *pixel_formats_blob_ptr;
+
+ /** @job_lock: Protects job_queue */
+ spinlock_t job_lock;
+
+ /**
+ * @job_queue:
+ *
+ * Holds a list of a connector's writeback jobs; the last item is the
+ * most recent. The first item may be either waiting for the hardware
+ * to begin writing, or currently being written.
+ *
+ * See also: drm_writeback_queue_job() and
+ * drm_writeback_signal_completion()
+ */
+ struct list_head job_queue;
+
+ /**
+ * @fence_context:
+ *
+ * timeline context used for fence operations.
+ */
+ unsigned int fence_context;
+ /**
+ * @fence_lock:
+ *
+ * spinlock to protect the fences in the fence_context.
+ */
+ spinlock_t fence_lock;
+ /**
+ * @fence_seqno:
+ *
+ * Seqno variable used as monotonic counter for the fences
+ * created on the connector's timeline.
+ */
+ unsigned long fence_seqno;
+ /**
+ * @timeline_name:
+ *
+ * The name of the connector's fence timeline.
+ */
+ char timeline_name[32];
+};
+
+struct drm_writeback_job {
+ /**
+ * @cleanup_work:
+ *
+ * Used to allow drm_writeback_signal_completion to defer dropping the
+ * framebuffer reference to a workqueue
+ */
+ struct work_struct cleanup_work;
+
+ /**
+ * @list_entry:
+ *
+ * List item for the writeback connector's @job_queue
+ */
+ struct list_head list_entry;
+
+ /**
+ * @fb:
+ *
+ * Framebuffer to be written to by the writeback connector. Do not set
+ * directly, use drm_atomic_set_writeback_fb_for_connector()
+ */
+ struct drm_framebuffer *fb;
+
+ /**
+ * @out_fence:
+ *
+ * Fence which will signal once the writeback has completed
+ */
+ struct dma_fence *out_fence;
+};
+
+static inline struct drm_writeback_connector *
+drm_connector_to_writeback(struct drm_connector *connector)
+{
+ return container_of(connector, struct drm_writeback_connector, base);
+}
+
+int drm_writeback_connector_init(struct drm_device *dev,
+ struct drm_writeback_connector *wb_connector,
+ const struct drm_connector_funcs *con_funcs,
+ const struct drm_encoder_helper_funcs *enc_helper_funcs,
+ const u32 *formats, int n_formats);
+
+void drm_writeback_queue_job(struct drm_writeback_connector *wb_connector,
+ struct drm_writeback_job *job);
+
+void drm_writeback_cleanup_job(struct drm_writeback_job *job);
+
+void
+drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector,
+ int status);
+
+struct dma_fence *
+drm_writeback_get_out_fence(struct drm_writeback_connector *wb_connector);
+#endif