v4.19.13 snapshot.
diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h
new file mode 100644
index 0000000..971bb78
--- /dev/null
+++ b/include/drm/drm_client.h
@@ -0,0 +1,140 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _DRM_CLIENT_H_
+#define _DRM_CLIENT_H_
+
+#include <linux/types.h>
+
+struct drm_client_dev;
+struct drm_device;
+struct drm_file;
+struct drm_framebuffer;
+struct drm_gem_object;
+struct drm_minor;
+struct module;
+
+/**
+ * struct drm_client_funcs - DRM client callbacks
+ */
+struct drm_client_funcs {
+ /**
+ * @owner: The module owner
+ */
+ struct module *owner;
+
+ /**
+ * @unregister:
+ *
+ * Called when &drm_device is unregistered. The client should respond by
+ * releasing it's resources using drm_client_release().
+ *
+ * This callback is optional.
+ */
+ void (*unregister)(struct drm_client_dev *client);
+
+ /**
+ * @restore:
+ *
+ * Called on drm_lastclose(). The first client instance in the list that
+ * returns zero gets the privilege to restore and no more clients are
+ * called. This callback is not called after @unregister has been called.
+ *
+ * This callback is optional.
+ */
+ int (*restore)(struct drm_client_dev *client);
+
+ /**
+ * @hotplug:
+ *
+ * Called on drm_kms_helper_hotplug_event().
+ * This callback is not called after @unregister has been called.
+ *
+ * This callback is optional.
+ */
+ int (*hotplug)(struct drm_client_dev *client);
+};
+
+/**
+ * struct drm_client_dev - DRM client instance
+ */
+struct drm_client_dev {
+ /**
+ * @dev: DRM device
+ */
+ struct drm_device *dev;
+
+ /**
+ * @name: Name of the client.
+ */
+ const char *name;
+
+ /**
+ * @list:
+ *
+ * List of all clients of a DRM device, linked into
+ * &drm_device.clientlist. Protected by &drm_device.clientlist_mutex.
+ */
+ struct list_head list;
+
+ /**
+ * @funcs: DRM client functions (optional)
+ */
+ const struct drm_client_funcs *funcs;
+
+ /**
+ * @file: DRM file
+ */
+ struct drm_file *file;
+};
+
+int drm_client_init(struct drm_device *dev, struct drm_client_dev *client,
+ const char *name, const struct drm_client_funcs *funcs);
+void drm_client_release(struct drm_client_dev *client);
+void drm_client_add(struct drm_client_dev *client);
+
+void drm_client_dev_unregister(struct drm_device *dev);
+void drm_client_dev_hotplug(struct drm_device *dev);
+void drm_client_dev_restore(struct drm_device *dev);
+
+/**
+ * struct drm_client_buffer - DRM client buffer
+ */
+struct drm_client_buffer {
+ /**
+ * @client: DRM client
+ */
+ struct drm_client_dev *client;
+
+ /**
+ * @handle: Buffer handle
+ */
+ u32 handle;
+
+ /**
+ * @pitch: Buffer pitch
+ */
+ u32 pitch;
+
+ /**
+ * @gem: GEM object backing this buffer
+ */
+ struct drm_gem_object *gem;
+
+ /**
+ * @vaddr: Virtual address for the buffer
+ */
+ void *vaddr;
+
+ /**
+ * @fb: DRM framebuffer
+ */
+ struct drm_framebuffer *fb;
+};
+
+struct drm_client_buffer *
+drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format);
+void drm_client_framebuffer_delete(struct drm_client_buffer *buffer);
+
+int drm_client_debugfs_init(struct drm_minor *minor);
+
+#endif