HYL_OK3568_LINUX/buildroot/package/weston/0015-backend-drm-Support-selecting-monitors.patch

From 14a416a3c5959e53d0de2e8cc7b8221a3544be5a Mon Sep 17 00:00:00 2001
From: Jeffy Chen <jeffy.chen@rock-chips.com>
Date: Tue, 23 Jun 2020 10:05:48 +0800
Subject: [PATCH 15/93] backend-drm: Support selecting monitors

Using these environments:

WESTON_DRM_PRIMARY:
  Specify primary connector.
WESTON_DRM_SINGLE_HEAD:
  Force using single connector.
WESTON_DRM_HEAD_FALLBACK:
  Fallback to any available connector if none matched.
WESTON_DRM_HEAD_FALLBACK_ALL:
  Fallback to all available connector if none matched.
WESTON_DRM_PREFER_EXTERNAL_DUAL:
  Prefer external connectors, and also enable internal ones.
WESTON_DRM_PREFER_EXTERNAL:
  Prefer external connectors, and disable internal ones if any matched.

WESTON_DRM_HEAD_MODE:
  default(match primary->internal->external)
  primary(match primary only)
  internal(match primary->internal)
  external(match primary->external)
  external-dual(match primary->external->internal)

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
---
 compositor/main.c                    |  22 +-
 desktop-shell/shell.c                |  26 +-
 include/libweston/libweston.h        |   2 +
 libweston/backend-drm/drm-internal.h |  24 ++
 libweston/backend-drm/drm.c          | 378 ++++++++++++++++++++++++---
 libweston/backend-drm/kms.c          |  42 ++-
 libweston/compositor.c               |  42 ++-
 7 files changed, 477 insertions(+), 59 deletions(-)

diff --git a/compositor/main.c b/compositor/main.c
index 57a52b6..dcfe85b 100644
--- a/compositor/main.c
+++ b/compositor/main.c
@@ -2326,7 +2326,7 @@ drm_head_prepare_enable(struct wet_compositor *wet,
 	char *output_name = NULL;
 	char *mode = NULL;
 
-	section = drm_config_find_controlling_output_section(wet->config, name);
+	section = head->section;
 	if (section) {
 		/* skip outputs that are explicitly off, or non-desktop and not
 		 * explicitly enabled. The backend turns them off automatically.
@@ -2356,11 +2356,10 @@ static bool
 drm_head_should_force_enable(struct wet_compositor *wet,
 			     struct weston_head *head)
 {
-	const char *name = weston_head_get_name(head);
 	struct weston_config_section *section;
 	bool force;
 
-	section = drm_config_find_controlling_output_section(wet->config, name);
+	section = head->section;
 	if (!section)
 		return false;
 
@@ -2551,6 +2550,21 @@ drm_head_disable(struct weston_head *head)
 		wet_output_destroy(output);
 }
 
+static bool
+drm_head_update_output_section(struct weston_head *head)
+{
+	struct weston_compositor *compositor = head->compositor;
+	struct wet_compositor *wet = to_wet_compositor(compositor);
+	const char *name = weston_head_get_name(head);
+
+	if (head->section)
+		return true;
+
+	head->section =
+		drm_config_find_controlling_output_section(wet->config, name);
+	return !!head->section;
+}
+
 static void
 drm_heads_changed(struct wl_listener *listener, void *arg)
 {
@@ -2566,6 +2580,8 @@ drm_heads_changed(struct wl_listener *listener, void *arg)
 	 * output.
 	 */
 	while ((head = weston_compositor_iterate_heads(compositor, head))) {
+		drm_head_update_output_section(head);
+
 		connected = weston_head_is_connected(head);
 		enabled = weston_head_is_enabled(head);
 		changed = weston_head_is_device_changed(head);
diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c
index 79e20ad..89ea491 100644
--- a/desktop-shell/shell.c
+++ b/desktop-shell/shell.c
@@ -3550,6 +3550,9 @@ shell_fade_done_for_output(struct weston_view_animation *animation, void *data)
 	struct shell_output *shell_output = data;
 	struct desktop_shell *shell = shell_output->shell;
 
+	if (!shell_output->fade.curtain)
+		return;
+
 	shell_output->fade.animation = NULL;
 	switch (shell_output->fade.type) {
 	case FADE_IN:
@@ -4334,8 +4337,12 @@ shell_output_destroy(struct shell_output *shell_output)
 		shell_output->fade.animation = NULL;
 	}
 
-	if (shell_output->fade.curtain)
-		weston_curtain_destroy(shell_output->fade.curtain);
+	if (shell_output->fade.curtain) {
+		struct weston_curtain *curtain = shell_output->fade.curtain;
+
+		shell_output->fade.curtain = NULL;
+		weston_curtain_destroy(curtain);
+	}
 
 	if (shell_output->fade.startup_timer)
 		wl_event_source_remove(shell_output->fade.startup_timer);
@@ -4438,12 +4445,25 @@ handle_output_move_layer(struct desktop_shell *shell,
 static void
 handle_output_move(struct wl_listener *listener, void *data)
 {
+	struct weston_output *output = data;
+	struct weston_compositor *compositor = output->compositor;
 	struct desktop_shell *shell;
 
 	shell = container_of(listener, struct desktop_shell,
 			     output_move_listener);
 
-	shell_for_each_layer(shell, handle_output_move_layer, data);
+	if (shell->lock_surface)
+		shell->lock_surface->committed(shell->lock_surface, 0, 0);
+
+	/* Only move normal layers for non-default output */
+	if (output != get_default_output(compositor)) {
+		shell_for_each_layer(shell, handle_output_move_layer, data);
+		return;
+	}
+
+	handle_output_move_layer(shell, &shell->lock_layer, data);
+	handle_output_move_layer(shell, &shell->background_layer, data);
+	handle_output_move_layer(shell, &shell->panel_layer, data);
 }
 
 static void
diff --git a/include/libweston/libweston.h b/include/libweston/libweston.h
index 984d5f3..d35963f 100644
--- a/include/libweston/libweston.h
+++ b/include/libweston/libweston.h
@@ -399,6 +399,8 @@ struct weston_head {
 
 	/** Opaque pointer used by backends to identify heads as theirs */
 	const void *backend_id;
+
+	struct weston_config_section *section; /**< config section **/
 };
 
 /** Output properties derived from its color characteristics and profile
diff --git a/libweston/backend-drm/drm-internal.h b/libweston/backend-drm/drm-internal.h
index f4b8ed8..ec8bf0e 100644
--- a/libweston/backend-drm/drm-internal.h
+++ b/libweston/backend-drm/drm-internal.h
@@ -110,6 +110,10 @@
 
 #define MAX_CLONED_CONNECTORS 4
 
+/* Min duration between drm outputs update requests, to avoid glith */
+#define DRM_MIN_UPDATE_MS	1000
+
+#define DRM_RESIZE_FREEZE_MS    600
 
 /**
  * Represents the values of an enum-type KMS property
@@ -268,6 +272,7 @@ struct drm_device {
 		int fd;
 		char *filename;
 		dev_t devnum;
+		char *syspath;
 	} drm;
 
 	/* drm_crtc::link */
@@ -302,6 +307,10 @@ struct drm_device {
 	int min_height, max_height;
 };
 
+struct drm_head;
+struct drm_backend;
+typedef bool (*drm_head_match_t) (struct drm_backend *, struct drm_head *);
+
 struct drm_backend {
 	struct weston_backend base;
 	struct weston_compositor *compositor;
@@ -327,6 +336,19 @@ struct drm_backend {
 	bool shutting_down;
 
 	struct weston_log_scope *debug;
+
+	struct wl_event_source *hotplug_timer;
+	bool pending_update;
+	int64_t last_update_ms;
+	int64_t last_resize_ms;
+	int64_t resize_freeze_ms;
+
+	bool single_head;
+	bool head_fallback;
+	bool head_fallback_all;
+	drm_head_match_t *head_matches;
+	struct drm_head *primary_head;
+	struct wl_listener output_create_listener;
 };
 
 struct drm_mode {
@@ -589,6 +611,8 @@ struct drm_output {
 	void (*virtual_destroy)(struct weston_output *base);
 
 	submit_frame_cb virtual_submit_frame;
+
+	bool state_invalid;
 };
 
 void
diff --git a/libweston/backend-drm/drm.c b/libweston/backend-drm/drm.c
index 711ed5b..f5ac1b6 100644
--- a/libweston/backend-drm/drm.c
+++ b/libweston/backend-drm/drm.c
@@ -30,6 +30,7 @@
 #include "config.h"
 
 #include <errno.h>
+#include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <ctype.h>
@@ -47,6 +48,7 @@
 
 #include <libudev.h>
 
+#include <libweston/config-parser.h>
 #include <libweston/libweston.h>
 #include <libweston/backend-drm.h>
 #include <libweston/weston-log.h>
@@ -68,6 +70,43 @@
 
 static const char default_seat[] = "seat0";
 
+static inline bool
+drm_head_is_external(struct drm_head *head)
+{
+	drmModeConnector *conn = head->connector.conn;
+	switch (conn->connector_type) {
+		case DRM_MODE_CONNECTOR_LVDS:
+		case DRM_MODE_CONNECTOR_eDP:
+#ifdef DRM_MODE_CONNECTOR_DSI
+		case DRM_MODE_CONNECTOR_DSI:
+#endif
+			return false;
+		default:
+			return true;
+	}
+};
+
+static void
+drm_backend_update_outputs(struct drm_backend *b)
+{
+	struct weston_output *primary;
+
+	if (!b->primary_head)
+		return;
+
+	primary = b->primary_head->base.output;
+	if (!primary)
+		return;
+
+	wl_list_remove(&primary->link);
+	wl_list_insert(&b->compositor->output_list, &primary->link);
+
+	/* Reflow outputs */
+	weston_compositor_reflow_outputs(b->compositor);
+
+	weston_compositor_damage_all(b->compositor);
+}
+
 static void
 drm_backend_create_faked_zpos(struct drm_backend *b)
 {
@@ -464,18 +503,36 @@ drm_output_repaint(struct weston_output *output_base, pixman_region32_t *damage)
 	struct drm_plane_state *scanout_state;
 	struct drm_pending_state *pending_state;
 	struct drm_device *device;
+	struct drm_backend *b;
+	struct timespec now;
+	int64_t now_ms;
 
 	assert(output);
 	assert(!output->virtual);
 
 	device = output->device;
 	pending_state = device->repaint_data;
+	b = device->backend;
 
 	if (output->disable_pending || output->destroy_pending)
 		goto err;
 
 	assert(!output->state_last);
 
+	weston_compositor_read_presentation_clock(b->compositor, &now);
+	now_ms = timespec_to_msec(&now);
+	if (now_ms < b->last_resize_ms + DRM_RESIZE_FREEZE_MS) {
+		/* Resize fullscreen/maxmium views(not always success) */
+		if (now_ms < b->last_resize_ms + DRM_RESIZE_FREEZE_MS)
+			wl_signal_emit(&b->compositor->output_resized_signal,
+				       output);
+
+		weston_output_damage(output_base);
+		weston_output_finish_frame(output_base, NULL,
+					   WP_PRESENTATION_FEEDBACK_INVALID);
+		return 0;
+	}
+
 	/* If planes have been disabled in the core, we might not have
 	 * hit assign_planes at all, so might not have valid output state
 	 * here. */
@@ -504,7 +561,7 @@ drm_output_repaint(struct weston_output *output_base, pixman_region32_t *damage)
 
 err:
 	drm_output_state_free(state);
-	return -1;
+	return 0;
 }
 
 /* Determine the type of vblank synchronization to use for the output.
@@ -743,6 +800,7 @@ drm_output_apply_mode(struct drm_output *output)
 	 *      content.
 	 */
 	device->state_invalid = true;
+	output->state_invalid = true;
 
 	if (b->use_pixman) {
 		drm_output_fini_pixman(output);
@@ -1322,6 +1380,7 @@ drm_output_attach_head(struct weston_output *output_base,
 {
 	struct drm_backend *b = to_drm_backend(output_base->compositor);
 	struct drm_device *device = b->drm;
+	struct drm_output *output = to_drm_output(output_base);
 
 	if (wl_list_length(&output_base->head_list) >= MAX_CLONED_CONNECTORS)
 		return -1;
@@ -1339,6 +1398,7 @@ drm_output_attach_head(struct weston_output *output_base,
 	 * will not clear the flag before this output is updated?
 	 */
 	device->state_invalid = true;
+	output->state_invalid = true;
 
 	weston_output_schedule_repaint(output_base);
 
@@ -1351,6 +1411,7 @@ drm_output_detach_head(struct weston_output *output_base,
 {
 	struct drm_backend *b = to_drm_backend(output_base->compositor);
 	struct drm_device *device = b->drm;
+	struct drm_output *output = to_drm_output(output_base);
 
 	if (!output_base->enabled)
 		return;
@@ -1359,6 +1420,7 @@ drm_output_detach_head(struct weston_output *output_base,
 	 * be driven. */
 	/* XXX: Ideally we'd do this per-output, not globally. */
 	device->state_invalid = true;
+	output->state_invalid = true;
 
 	weston_output_schedule_repaint(output_base);
 }
@@ -1917,6 +1979,8 @@ drm_output_enable(struct weston_output *base)
 	output->base.switch_mode = drm_output_switch_mode;
 	output->base.set_gamma = drm_output_set_gamma;
 
+	output->state_invalid = true;
+
 	weston_log("Output %s (crtc %d) video modes:\n",
 		   output->base.name, output->crtc->crtc_id);
 	drm_output_print_modes(output);
@@ -2278,8 +2342,7 @@ drm_head_create(struct drm_device *device, drmModeConnector *conn,
 
 	head->backlight = backlight_init(drm_device, conn->connector_type);
 
-	if (conn->connector_type == DRM_MODE_CONNECTOR_LVDS ||
-	    conn->connector_type == DRM_MODE_CONNECTOR_eDP)
+	if (!drm_head_is_external(head))
 		weston_head_set_internal(&head->base);
 
 	if (drm_head_read_current_setup(head, device) < 0) {
@@ -2447,56 +2510,54 @@ drm_backend_add_connector(struct drm_device *device, drmModeConnector *conn,
 	return ret;
 }
 
-/** Find all connectors of the fd and create drm_head or drm_writeback objects
- * (depending on the type of connector they are) for each of them
- *
- * These objects are added to the DRM-backend lists of heads and writebacks.
- *
- * @param device The DRM device structure
- * @param drm_device udev device pointer
- * @param resources The DRM resources, it is taken with drmModeGetResources
- * @return 0 on success, -1 on failure
- */
-static int
-drm_backend_discover_connectors(struct drm_device *device,
-				struct udev_device *drm_device,
-				drmModeRes *resources)
+static bool
+resources_has_connector(drmModeRes *resources, uint32_t connector_id)
 {
-	drmModeConnector *conn;
-	int i, ret;
+	for (int i = 0; i < resources->count_connectors; i++) {
+		if (resources->connectors[i] == connector_id)
+			return true;
+	}
 
-	device->min_width  = resources->min_width;
-	device->max_width  = resources->max_width;
-	device->min_height = resources->min_height;
-	device->max_height = resources->max_height;
+	return false;
+}
 
-	for (i = 0; i < resources->count_connectors; i++) {
-		uint32_t connector_id = resources->connectors[i];
+/* based on compositor/main.c#drm_head_prepare_enable() */
+static bool
+drm_head_is_available(struct weston_head *head)
+{
+	struct weston_config_section *section;
+	char *mode = NULL;
 
-		conn = drmModeGetConnector(device->drm.fd, connector_id);
-		if (!conn)
-			continue;
+	section = head->section;
+	if (!section)
+		return true;
 
-		ret = drm_backend_add_connector(device, conn, drm_device);
-		if (ret < 0)
-			drmModeFreeConnector(conn);
+	/* skip outputs that are explicitly off, or non-desktop and not
+	 * explicitly enabled.
+	 */
+	weston_config_section_get_string(section, "mode", &mode, NULL);
+	if (mode && strcmp(mode, "off") == 0) {
+		free(mode);
+		return false;
 	}
 
-	return 0;
+	if (!mode && weston_head_is_non_desktop(head))
+		return false;
+
+	free(mode);
+	return true;
 }
 
 static bool
-resources_has_connector(drmModeRes *resources, uint32_t connector_id)
+drm_head_match_fallback(struct drm_backend *b, struct drm_head *head)
 {
-	for (int i = 0; i < resources->count_connectors; i++) {
-		if (resources->connectors[i] == connector_id)
-			return true;
-	}
+	if (b->head_fallback_all)
+		return true;
 
-	return false;
+	return b->head_fallback && !b->primary_head;
 }
 
-static void
+static int
 drm_backend_update_connectors(struct drm_device *device,
 			      struct udev_device *drm_device)
 {
@@ -2504,17 +2565,24 @@ drm_backend_update_connectors(struct drm_device *device,
 	drmModeRes *resources;
 	drmModeConnector *conn;
 	struct weston_head *base, *base_next;
-	struct drm_head *head;
+	struct drm_head *head, *old_primary_head;
 	struct drm_writeback *writeback, *writeback_next;
+	drm_head_match_t *match = b->head_matches;
+	struct timespec now;
 	uint32_t connector_id;
 	int i, ret;
 
 	resources = drmModeGetResources(device->drm.fd);
 	if (!resources) {
 		weston_log("drmModeGetResources failed\n");
-		return;
+		return -1;
 	}
 
+	device->min_width  = resources->min_width;
+	device->max_width  = resources->max_width;
+	device->min_height = resources->min_height;
+	device->max_height = resources->max_height;
+
 	/* collect new connectors that have appeared, e.g. MST */
 	for (i = 0; i < resources->count_connectors; i++) {
 		connector_id = resources->connectors[i];
@@ -2576,6 +2644,65 @@ drm_backend_update_connectors(struct drm_device *device,
 	}
 
 	drmModeFreeResources(resources);
+
+	old_primary_head = b->primary_head;
+	b->primary_head = NULL;
+
+	wl_list_for_each_safe(base, base_next,
+			      &b->compositor->head_list, compositor_link)
+		weston_head_set_connection_status(base, false);
+
+	/* Re-connect matched heads and find primary head */
+	while (*match) {
+		wl_list_for_each_safe(base, base_next,
+				      &b->compositor->head_list,
+				      compositor_link) {
+			drmModeConnector *conn;
+
+			if (!drm_head_is_available(base))
+				continue;
+
+			head = to_drm_head(base);
+			conn = head->connector.conn;
+
+			if (conn->connection != DRM_MODE_CONNECTED ||
+			    !(*match)(b, head))
+				continue;
+
+			weston_head_set_connection_status(base, true);
+
+			if (!b->primary_head) {
+				b->primary_head = head;
+
+				/* Done the single-head match */
+				if (b->single_head)
+					goto match_done;
+			}
+		}
+
+		/* Done the fallback match */
+		if (*match == drm_head_match_fallback)
+			goto match_done;
+
+		match++;
+
+		/* Try the fallback match */
+		if (!match && !b->primary_head)
+			*match = drm_head_match_fallback;
+	}
+match_done:
+
+	drm_backend_update_outputs(b);
+
+	weston_compositor_read_presentation_clock(b->compositor, &now);
+	b->last_update_ms = timespec_to_msec(&now);
+
+	/* Assume primary output's size changed */
+	if (b->primary_head && old_primary_head &&
+	    b->primary_head != old_primary_head)
+		b->last_resize_ms = b->last_update_ms;
+
+	return 0;
 }
 
 static enum wdrm_connector_property
@@ -2666,6 +2793,50 @@ udev_event_is_conn_prop_change(struct drm_backend *b,
 	return 1;
 }
 
+static void
+udev_hotplug_event(struct drm_device *device, struct udev_device *udev_device)
+{
+	struct drm_backend *b = device->backend;
+	struct timespec now;
+	int64_t now_ms, next_ms;
+
+	weston_compositor_read_presentation_clock(b->compositor, &now);
+	now_ms = timespec_to_msec(&now);
+
+	/* Already have a pending request */
+	if (b->pending_update)
+		return;
+
+	next_ms = b->last_update_ms + DRM_MIN_UPDATE_MS;
+	if (next_ms <= now_ms) {
+		/* Long enough to trigger a new request */
+		drm_backend_update_connectors(device, udev_device);
+	} else {
+		/* Too close to the last request, schedule a new one */
+		b->pending_update = true;
+		wl_event_source_timer_update(b->hotplug_timer,
+					     next_ms - now_ms);
+	}
+}
+
+static int
+hotplug_timer_handler(void *data)
+{
+	struct drm_device *device = data;
+	struct drm_backend *b = device->backend;
+	struct udev_device *udev_device;
+	struct udev *udev;
+
+	udev = udev_monitor_get_udev(b->udev_monitor);
+	udev_device = udev_device_new_from_syspath(udev, device->drm.syspath);
+
+	drm_backend_update_connectors(device, udev_device);
+	b->pending_update = false;
+
+	udev_device_unref(udev_device);
+	return 0;
+}
+
 static int
 udev_drm_event(int fd, uint32_t mask, void *data)
 {
@@ -2679,7 +2850,7 @@ udev_drm_event(int fd, uint32_t mask, void *data)
 		if (udev_event_is_conn_prop_change(b, event, &conn_id, &prop_id))
 			drm_backend_update_conn_props(b, conn_id, prop_id);
 		else
-			drm_backend_update_connectors(b->drm, event);
+			udev_hotplug_event(b->drm, event);
 	}
 
 	udev_device_unref(event);
@@ -2698,6 +2869,7 @@ drm_destroy(struct weston_compositor *ec)
 
 	udev_input_destroy(&b->input);
 
+	wl_event_source_remove(b->hotplug_timer);
 	wl_event_source_remove(b->udev_drm_source);
 	wl_event_source_remove(b->drm_source);
 
@@ -2750,6 +2922,10 @@ session_notify(struct wl_listener *listener, void *data)
 		weston_compositor_wake(compositor);
 		weston_compositor_damage_all(compositor);
 		device->state_invalid = true;
+
+		wl_list_for_each(output, &compositor->output_list, link)
+			to_drm_output(output)->state_invalid = true;
+
 		udev_input_enable(&b->input);
 	} else {
 		weston_log("deactivating session\n");
@@ -3106,6 +3282,14 @@ recorder_binding(struct weston_keyboard *keyboard, const struct timespec *time,
 }
 #endif
 
+static void
+output_create_notify(struct wl_listener *listener, void *data)
+{
+	struct drm_backend *b = container_of(listener, struct drm_backend,
+					     output_create_listener);
+
+	drm_backend_update_outputs(b);
+}
 
 static const struct weston_drm_output_api api = {
 	drm_output_set_mode,
@@ -3114,6 +3298,63 @@ static const struct weston_drm_output_api api = {
 	drm_output_set_max_bpc,
 };
 
+enum drm_head_mode {
+	DRM_HEAD_MODE_DEFAULT,
+	DRM_HEAD_MODE_PRIMARY,
+	DRM_HEAD_MODE_INTERNAL,
+	DRM_HEAD_MODE_EXTERNAL,
+	DRM_HEAD_MODE_EXTERNAL_DUAL,
+};
+
+static bool
+drm_head_match_primary(struct drm_backend *b, struct drm_head *head)
+{
+	const char *buf = getenv("WESTON_DRM_PRIMARY");
+	return buf && !strcmp(buf, head->base.name);
+}
+
+static bool
+drm_head_match_external(struct drm_backend *b, struct drm_head *head)
+{
+	return drm_head_is_external(head);
+}
+
+static bool
+drm_head_match_internal(struct drm_backend *b, struct drm_head *head)
+{
+	return !drm_head_is_external(head);
+}
+
+#define DRM_HEAD_MAX_MATCHES 5
+static drm_head_match_t drm_head_matches[][DRM_HEAD_MAX_MATCHES] = {
+	[DRM_HEAD_MODE_DEFAULT] = {
+		drm_head_match_primary,
+		drm_head_match_internal,
+		drm_head_match_external,
+		NULL,
+	},
+	[DRM_HEAD_MODE_PRIMARY] = {
+		drm_head_match_primary,
+		NULL,
+	},
+	[DRM_HEAD_MODE_INTERNAL] = {
+		drm_head_match_primary,
+		drm_head_match_internal,
+		NULL,
+	},
+	[DRM_HEAD_MODE_EXTERNAL] = {
+		drm_head_match_primary,
+		drm_head_match_external,
+		NULL,
+	},
+	[DRM_HEAD_MODE_EXTERNAL_DUAL] = {
+		drm_head_match_primary,
+		drm_head_match_external,
+		drm_head_match_internal,
+		NULL,
+	},
+};
+
 static struct drm_backend *
 drm_backend_create(struct weston_compositor *compositor,
 		   struct weston_drm_backend_config *config)
@@ -3125,7 +3366,9 @@ drm_backend_create(struct weston_compositor *compositor,
 	const char *seat_id = default_seat;
 	const char *session_seat;
 	struct weston_drm_format_array *scanout_formats;
+	enum drm_head_mode head_mode = DRM_HEAD_MODE_DEFAULT;
 	drmModeRes *res;
+	char *buf;
 	int ret;
 
 	session_seat = getenv("XDG_SEAT");
@@ -3141,6 +3384,48 @@ drm_backend_create(struct weston_compositor *compositor,
 	if (b == NULL)
 		return NULL;
 
+	buf = getenv("WESTON_DRM_SINGLE_HEAD");
+	if (buf && buf[0] == '1')
+		b->single_head = true;
+
+	buf = getenv("WESTON_DRM_HEAD_FALLBACK");
+	if (buf && buf[0] == '1')
+		b->head_fallback = true;
+
+	buf = getenv("WESTON_DRM_HEAD_FALLBACK_ALL");
+	if (buf && buf[0] == '1')
+		b->head_fallback_all = true;
+
+	buf = getenv("WESTON_DRM_PREFER_EXTERNAL");
+	if (buf && buf[0] == '1') {
+		head_mode = DRM_HEAD_MODE_EXTERNAL;
+		b->head_fallback = true;
+	}
+
+	buf = getenv("WESTON_DRM_PREFER_EXTERNAL_DUAL");
+	if (buf && buf[0] == '1')
+		head_mode = DRM_HEAD_MODE_EXTERNAL_DUAL;
+
+	buf = getenv("WESTON_DRM_HEAD_MODE");
+	if (buf) {
+		if (!strcmp(buf, "primary"))
+			head_mode = DRM_HEAD_MODE_PRIMARY;
+		else if (!strcmp(buf, "internal"))
+			head_mode = DRM_HEAD_MODE_INTERNAL;
+		else if (!strcmp(buf, "external"))
+			head_mode = DRM_HEAD_MODE_EXTERNAL;
+		else if (!strcmp(buf, "external-dual"))
+			head_mode = DRM_HEAD_MODE_EXTERNAL_DUAL;
+	}
+
+	b->head_matches = drm_head_matches[head_mode];
+
+	buf = getenv("WESTON_DRM_RESIZE_FREEZE_MS");
+	if (buf)
+		b->resize_freeze_ms = atoi(buf);
+	else
+		b->resize_freeze_ms = DRM_RESIZE_FREEZE_MS;
+
 	device = zalloc(sizeof *device);
 	if (device == NULL)
 		return NULL;
@@ -3241,7 +3526,7 @@ drm_backend_create(struct weston_compositor *compositor,
 	}
 
 	wl_list_init(&b->drm->writeback_connector_list);
-	if (drm_backend_discover_connectors(b->drm, drm_device, res) < 0) {
+	if (drm_backend_update_connectors(b->drm, drm_device) < 0) {
 		weston_log("Failed to create heads for %s\n", b->drm->drm.filename);
 		goto err_udev_input;
 	}
@@ -3280,6 +3565,10 @@ drm_backend_create(struct weston_compositor *compositor,
 
 	udev_device_unref(drm_device);
 
+	b->output_create_listener.notify = output_create_notify;
+	wl_signal_add(&b->compositor->output_created_signal,
+		      &b->output_create_listener);
+
 	weston_compositor_add_debug_binding(compositor, KEY_O,
 					    planes_binding, b);
 	weston_compositor_add_debug_binding(compositor, KEY_C,
@@ -3339,6 +3628,9 @@ drm_backend_create(struct weston_compositor *compositor,
 		goto err_udev_monitor;
 	}
 
+	b->hotplug_timer =
+		wl_event_loop_add_timer(loop, hotplug_timer_handler, b->drm);
+
 	return b;
 
 err_udev_monitor:
diff --git a/libweston/backend-drm/kms.c b/libweston/backend-drm/kms.c
index 735196b..c7dc2f8 100644
--- a/libweston/backend-drm/kms.c
+++ b/libweston/backend-drm/kms.c
@@ -683,6 +683,8 @@ drm_output_apply_state_legacy(struct drm_output_state *state)
 
 	scanout_state =
 		drm_output_state_get_existing_plane(state, scanout_plane);
+	if (!scanout_state || !scanout_state->fb)
+		return 0;
 
 	/* The legacy SetCrtc API doesn't allow us to do scaling, and the
 	 * legacy PageFlip API doesn't allow us to do clipping either. */
@@ -700,7 +702,7 @@ drm_output_apply_state_legacy(struct drm_output_state *state)
 	assert(scanout_state->in_fence_fd == -1);
 
 	mode = to_drm_mode(output->base.current_mode);
-	if (device->state_invalid ||
+	if (output->state_invalid ||
 	    !scanout_plane->state_cur->fb ||
 	    scanout_plane->state_cur->fb->strides[0] !=
 	    scanout_state->fb->strides[0]) {
@@ -714,6 +716,8 @@ drm_output_apply_state_legacy(struct drm_output_state *state)
 			weston_log("set mode failed: %s\n", strerror(errno));
 			goto err;
 		}
+
+		output->state_invalid = false;
 	}
 
 	pinfo = scanout_state->fb->format;
@@ -964,6 +968,11 @@ drm_output_apply_state_atomic(struct drm_output_state *state,
 		*flags |= DRM_MODE_ATOMIC_ALLOW_MODESET;
 	}
 
+	if (output->state_invalid) {
+		drm_debug(b, "\t\t\t[atomic] output state invalid, modeset OK\n");
+		*flags |= DRM_MODE_ATOMIC_ALLOW_MODESET;
+	}
+
 	if (state->dpms == WESTON_DPMS_ON) {
 		ret = drm_mode_ensure_blob(device, current_mode);
 		if (ret != 0)
@@ -1080,6 +1089,7 @@ drm_pending_state_apply_atomic(struct drm_pending_state *pending_state,
 	struct drm_output_state *output_state, *tmp;
 	struct drm_plane *plane;
 	drmModeAtomicReq *req = drmModeAtomicAlloc();
+	struct timespec now;
 	uint32_t flags;
 	int ret = 0;
 
@@ -1214,14 +1224,34 @@ drm_pending_state_apply_atomic(struct drm_pending_state *pending_state,
 		goto out;
 	}
 
+	weston_compositor_read_presentation_clock(b->compositor, &now);
+
 	wl_list_for_each_safe(output_state, tmp, &pending_state->output_list,
-			      link)
+			      link) {
+		struct drm_output *output = output_state->output;
+		struct drm_plane *scanout_plane = output->scanout_plane;
+		struct drm_plane_state *scanout_state =
+			drm_output_state_get_existing_plane(output_state,
+							    scanout_plane);
+
+		/* Don't have a new state to apply */
+		if (output_state->dpms == WESTON_DPMS_ON &&
+		    (!scanout_state || !scanout_state->fb))
+			continue;
+
 		drm_output_assign_state(output_state, mode);
+		output->state_invalid = false;
+
+		/* Not gonna receive flip event when dpms off */
+		if (output_state->dpms != WESTON_DPMS_ON)
+			drm_output_update_complete(output,
+						   WP_PRESENTATION_FEEDBACK_KIND_HW_COMPLETION,
+						   now.tv_sec,
+						   now.tv_nsec / 1000);
+	}
 
 	device->state_invalid = false;
 
-	assert(wl_list_empty(&pending_state->output_list));
-
 out:
 	drmModeAtomicFree(req);
 	drm_pending_state_free(pending_state);
@@ -1321,8 +1351,6 @@ drm_pending_state_apply(struct drm_pending_state *pending_state)
 
 	device->state_invalid = false;
 
-	assert(wl_list_empty(&pending_state->output_list));
-
 	drm_pending_state_free(pending_state);
 
 	return 0;
@@ -1374,8 +1402,6 @@ drm_pending_state_apply_sync(struct drm_pending_state *pending_state)
 
 	device->state_invalid = false;
 
-	assert(wl_list_empty(&pending_state->output_list));
-
 	drm_pending_state_free(pending_state);
 
 	return 0;
diff --git a/libweston/compositor.c b/libweston/compositor.c
index 9f8282b..2125f1a 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -160,6 +160,25 @@ weston_paint_node_destroy(struct weston_paint_node *pnode)
 	free(pnode);
 }
 
+static struct weston_layer *
+get_view_layer(struct weston_view *view);
+
+static bool
+weston_compositor_is_static_layer(struct weston_layer *layer)
+{
+	if (!layer)
+		return false;
+
+	switch (layer->position) {
+	case WESTON_LAYER_POSITION_BACKGROUND:
+	case WESTON_LAYER_POSITION_UI:
+	case WESTON_LAYER_POSITION_FADE:
+		return true;
+	default:
+		return false;
+	}
+}
+
 /** Send wl_output events for mode and scale changes
  *
  * \param head Send on all resources bound to this head.
@@ -1386,6 +1405,22 @@ weston_view_assign_output(struct weston_view *ev)
 	uint32_t max, area, mask;
 	pixman_box32_t *e;
 
+	/* The static views should bind to the specific output */
+	if (weston_compositor_is_static_layer(get_view_layer(ev))) {
+		struct weston_view *view = ev;
+
+		while (view && !(output = view->output))
+			view = view->geometry.parent;
+
+		if (output && !output->destroying)
+			ev->output_mask = 1u << output->id;
+		else
+			weston_view_set_output(ev, NULL);
+
+		weston_surface_assign_output(ev->surface);
+		return;
+	}
+
 	new_output = NULL;
 	max = 0;
 	mask = 0;
@@ -3301,6 +3336,7 @@ weston_output_repaint(struct weston_output *output)
 	if (output->dirty)
 		weston_output_update_matrix(output);
 
+	output->repaint_needed = false;
 	r = output->repaint(output, &output_damage);
 
 	/* Clear painted primary damage */
@@ -3309,8 +3345,9 @@ weston_output_repaint(struct weston_output *output)
 
 	pixman_region32_fini(&output_damage);
 
-	output->repaint_needed = false;
-	if (r == 0)
+	if (output->repaint_needed)
+		output->repaint_status = REPAINT_SCHEDULED;
+	else if (r == 0)
 		output->repaint_status = REPAINT_AWAITING_COMPLETION;
 
 	weston_compositor_repick(ec);
@@ -6911,6 +6948,7 @@ weston_compositor_remove_output(struct weston_output *output)
 	 * Use view_list in case the output did not go through repaint
 	 * after a view came on it, lacking a paint node. Just to be sure.
 	 */
+	weston_compositor_build_view_list(compositor, NULL);
 	wl_list_for_each(view, &compositor->view_list, link) {
 		if (view->output_mask & (1u << output->id))
 			weston_view_assign_output(view);
-- 
2.20.1