drm: samsung: support wake up during notify state changeandroid-u-qpr3-beta-2_r0.7android-u-qpr3-beta-2_r0.6android-u-qpr3-beta-2_r0.5android-u-qpr3-beta-2_r0.4android-u-qpr3-beta-2_r0.3android-u-qpr3-beta-2_r0.2android-u-qpr3-beta-2.1_r0.7android-u-qpr3-beta-2.1_r0.5android-u-qpr3-beta-2.1_r0.3android-u-qpr3-beta-2.1_r0.2android-u-qpr3-beta-2.1_r0.1android-15-dp-2_r0.6android-15-dp-2_r0.5android-15-dp-2_r0.4android-15-dp-2_r0.3android-15-dp-2_r0.2android-15-dp-2_r0.1android-gs-tangorpro-5.10-android14-qpr3-betaandroid-gs-raviole-5.10-android14-qpr3-betaandroid-gs-lynx-5.10-android14-qpr3-betaandroid-gs-felix-5.10-android14-qpr3-betaandroid-gs-bluejay-5.10-android14-qpr3-beta

While sysfs_notify initiates updates for state monitors upon state
changes, timely data updates can be hindered if user space processes
are frozen during notification. Support a mechanism to awaken the
system during notification if it need to ensure timely updates.

Bug: 311495944
Test: check refresh rate indicator is correct
Change-Id: I86d1f6e2e72bb54c10d394bd2634ce51147189e4
Signed-off-by: Midas Chien <midaschieh@google.com>
(cherry picked from commit 5cdb5034e2360b17e8cad80e7d5b5902c8ccfba3)

7 files changed, 80 insertions, 17 deletions

diff --git a/samsung/panel/Documentation/ABI/testing/sysfs-devices-platform-exynos-drm b/samsung/panel/Documentation/ABI/testing/sysfs-devices-platform-exynos-drm
index b9d7b13..3485a4a 100644
--- a/samsung/panel/Documentation/ABI/testing/sysfs-devices-platform-exynos-drm
+++ b/samsung/panel/Documentation/ABI/testing/sysfs-devices-platform-exynos-drm
@@ -15,3 +15,13 @@ Description:
 		The file provides the available display stats state.
 
 		Valid panels are 'primary-panel' or 'secondary-panel'.
+
+What:		/sys/class/backlight/<panel>-backlight/allow_wakeup_by_state_change
+Date:		January 2024
+KernelVersion:	5.10
+Contact:	"Midas Chien" <midaschieh@google.com>
+Description:
+		The file specifies whether the system can be awakened to receive
+		notifications regarding backlight state changes.
+
+		Valid panels are 'panel0' or 'panel1'.
diff --git a/samsung/panel/panel-boe-nt37290.c b/samsung/panel/panel-boe-nt37290.c
index 17e6b8e..1dfdce5 100644
--- a/samsung/panel/panel-boe-nt37290.c
+++ b/samsung/panel/panel-boe-nt37290.c
@@ -730,7 +730,7 @@ static bool nt37290_change_frequency(struct exynos_panel *ctx,
 	ctx->panel_idle_vrefresh = ctx->self_refresh_active ? spanel->hw_idle_vrefresh : 0;
 
 	if (updated) {
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, false);
 		te2_state_changed(ctx->bl);
 		dev_dbg(ctx->dev, "change to %dHz, idle %s, was_lp_mode %d\n",
 			vrefresh, idle_active ? "active" : "deactive", was_lp_mode);
@@ -771,7 +771,7 @@ static bool nt37290_set_self_refresh(struct exynos_panel *ctx, bool enable)
 	if (pmode->exynos_mode.is_lp_mode) {
 		/* set 10Hz while self refresh is active, otherwise clear it */
 		ctx->panel_idle_vrefresh = enable ? 10 : 0;
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, true);
 		return false;
 	}
 
diff --git a/samsung/panel/panel-samsung-drv.c b/samsung/panel/panel-samsung-drv.c
index 60cfaec..968c844 100644
--- a/samsung/panel/panel-samsung-drv.c
+++ b/samsung/panel/panel-samsung-drv.c
@@ -2024,7 +2024,7 @@ static void exynos_panel_pre_commit_properties(
 		DPU_ATRACE_BEGIN("set_hbm");
 		mutex_lock(&ctx->mode_lock);
 		exynos_panel_func->set_hbm_mode(ctx, conn_state->global_hbm_mode);
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, false);
 		mutex_unlock(&ctx->mode_lock);
 		DPU_ATRACE_END("set_hbm");
 		ghbm_updated = true;
@@ -2824,7 +2824,7 @@ static ssize_t hbm_mode_store(struct device *dev,
 
 	if (hbm_mode != ctx->hbm_mode) {
 		funcs->set_hbm_mode(ctx, hbm_mode);
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, false);
 	}
 
 unlock:
@@ -3253,6 +3253,34 @@ static ssize_t als_table_show(struct device *dev,
 
 static DEVICE_ATTR_RW(als_table);
 
+static ssize_t allow_wakeup_by_state_change_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct backlight_device *bd = to_backlight_device(dev);
+	struct exynos_panel *ctx = bl_get_data(bd);
+	int ret;
+
+	ret = kstrtobool(buf, &ctx->allow_wakeup_by_state_change);
+	if (ret) {
+		dev_err(ctx->dev, "invalid allow wakeup by state change value\n");
+		return ret;
+	}
+
+	return count;
+}
+
+static ssize_t allow_wakeup_by_state_change_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct backlight_device *bd = to_backlight_device(dev);
+	struct exynos_panel *ctx = bl_get_data(bd);
+
+	return sysfs_emit_at(buf, 0, "%d\n", ctx->allow_wakeup_by_state_change);
+}
+
+static DEVICE_ATTR_RW(allow_wakeup_by_state_change);
+
 static struct attribute *bl_device_attrs[] = {
 	&dev_attr_hbm_mode.attr,
 	&dev_attr_dimming_on.attr,
@@ -3263,6 +3291,7 @@ static struct attribute *bl_device_attrs[] = {
 	&dev_attr_lp_state.attr,
 	&dev_attr_te2_state.attr,
 	&dev_attr_als_table.attr,
+	&dev_attr_allow_wakeup_by_state_change.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(bl_device);
@@ -3331,7 +3360,7 @@ static void exynos_panel_set_backlight_state(struct exynos_panel *ctx,
 	mutex_unlock(&ctx->bl_state_lock);
 
 	if (state_changed) {
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, false);
 		dev_info(ctx->dev, "panel: %s | bl: brightness@%u, state@0x%x\n",
 			 exynos_panel_get_state_str(panel_state), bl->props.brightness,
 			 bl->props.state);
@@ -4143,7 +4172,7 @@ static void exynos_panel_bridge_mode_set(struct drm_bridge *bridge,
 				exynos_panel_set_backlight_state(
 					ctx, is_active ? PANEL_STATE_NORMAL : PANEL_STATE_OFF);
 			else if (ctx->bl)
-				notify_panel_mode_changed(ctx);
+				notify_panel_mode_changed(ctx, false);
 
 			if (!is_lp_mode)
 				exynos_panel_update_te2(ctx);
@@ -4615,10 +4644,20 @@ static int disp_stats_update_state(struct exynos_panel *ctx)
 
 static void notify_panel_mode_changed_worker(struct work_struct *work)
 {
+	struct notify_state_change *notify_state_change =
+		container_of(work, struct notify_state_change, work);
 	struct exynos_panel *ctx =
-		container_of(work, struct exynos_panel, notify_panel_mode_changed_work);
+		container_of(notify_state_change, struct exynos_panel, notify_panel_mode_changed);
 
 	disp_stats_update_state(ctx);
+
+	if (ctx->allow_wakeup_by_state_change && notify_state_change->abort_suspend) {
+		if (unlikely(!notify_state_change->ws))
+			dev_warn(ctx->dev, "wakeup source creation was unsuccessful\n");
+		else
+			pm_wakeup_ws_event(notify_state_change->ws, 0, true);
+	}
+
 	sysfs_notify(&ctx->bl->dev.kobj, NULL, "state");
 }
 
@@ -4653,6 +4692,11 @@ int exynos_panel_common_init(struct mipi_dsi_device *dsi,
 		dev_err(ctx->dev, "failed to register backlight device\n");
 		return PTR_ERR(ctx->bl);
 	}
+
+	ctx->notify_panel_mode_changed.ws = wakeup_source_register(dev, name);
+	if (!ctx->notify_panel_mode_changed.ws)
+		dev_warn(ctx->dev, "failed to register `%s` wakeup source\n", name);
+
 	ctx->bl->props.max_brightness = ctx->desc->max_brightness;
 	ctx->bl->props.brightness = ctx->desc->dft_brightness;
 
@@ -4688,7 +4732,7 @@ int exynos_panel_common_init(struct mipi_dsi_device *dsi,
 	ctx->panel_idle_enabled = exynos_panel_func && exynos_panel_func->set_self_refresh != NULL;
 	INIT_DELAYED_WORK(&ctx->idle_work, panel_idle_work);
 
-	INIT_WORK(&ctx->notify_panel_mode_changed_work, notify_panel_mode_changed_worker);
+	INIT_WORK(&ctx->notify_panel_mode_changed.work, notify_panel_mode_changed_worker);
 
 	mutex_init(&ctx->mode_lock);
 	mutex_init(&ctx->bl_state_lock);
diff --git a/samsung/panel/panel-samsung-drv.h b/samsung/panel/panel-samsung-drv.h
index e10d521..4f29db7 100644
--- a/samsung/panel/panel-samsung-drv.h
+++ b/samsung/panel/panel-samsung-drv.h
@@ -613,6 +613,12 @@ struct display_stats {
 	bool initialized;
 };
 
+struct notify_state_change {
+	struct work_struct work;
+	struct wakeup_source *ws;
+	bool abort_suspend;
+};
+
 struct exynos_panel {
 	struct device *dev;
 	struct drm_panel panel;
@@ -705,7 +711,9 @@ struct exynos_panel {
 	enum exynos_cabc_mode current_cabc_mode;
 
 	/* use for notify state changed */
-	struct work_struct notify_panel_mode_changed_work;
+	bool allow_wakeup_by_state_change;
+	struct notify_state_change notify_panel_mode_changed;
+	struct work_struct notify_brightness_changed_work;
 
 	/* use for display stats residence */
 	struct display_stats disp_stats;
@@ -852,9 +860,10 @@ static inline void te2_state_changed(struct backlight_device *bl)
 	sysfs_notify(&bl->dev.kobj, NULL, "te2_state");
 }
 
-static inline void notify_panel_mode_changed(struct exynos_panel *ctx)
+static inline void notify_panel_mode_changed(struct exynos_panel *ctx, bool abort_suspend)
 {
-	schedule_work(&ctx->notify_panel_mode_changed_work);
+	ctx->notify_panel_mode_changed.abort_suspend = abort_suspend;
+	schedule_work(&ctx->notify_panel_mode_changed.work);
 }
 
 static inline u32 get_current_frame_duration_us(struct exynos_panel *ctx)
diff --git a/samsung/panel/panel-samsung-s6e3hc3-c10.c b/samsung/panel/panel-samsung-s6e3hc3-c10.c
index b0c6ff6..94cc9e1 100644
--- a/samsung/panel/panel-samsung-s6e3hc3-c10.c
+++ b/samsung/panel/panel-samsung-s6e3hc3-c10.c
@@ -491,7 +491,7 @@ static void s6e3hc3_c10_update_refresh_mode(struct exynos_panel *ctx,
 	ctx->panel_idle_vrefresh = idle_vrefresh;
 	s6e3hc3_c10_update_panel_feat(ctx, pmode, false);
 	te2_state_changed(ctx->bl);
-	notify_panel_mode_changed(ctx);
+	notify_panel_mode_changed(ctx, false);
 }
 
 static void s6e3hc3_c10_change_frequency(struct exynos_panel *ctx,
diff --git a/samsung/panel/panel-samsung-s6e3hc3.c b/samsung/panel/panel-samsung-s6e3hc3.c
index 13c974a..30d8a5f 100644
--- a/samsung/panel/panel-samsung-s6e3hc3.c
+++ b/samsung/panel/panel-samsung-s6e3hc3.c
@@ -536,7 +536,7 @@ static bool s6e3hc3_set_self_refresh(struct exynos_panel *ctx, bool enable)
 	if (pmode->exynos_mode.is_lp_mode) {
 		/* set 10Hz while self refresh is active, otherwise clear it */
 		ctx->panel_idle_vrefresh = enable ? 10 : 0;
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, true);
 		return false;
 	}
 
@@ -550,7 +550,7 @@ static bool s6e3hc3_set_self_refresh(struct exynos_panel *ctx, bool enable)
 		if (pmode->idle_mode == IDLE_MODE_ON_INACTIVITY) {
 			/* simply update idle vrefresh follow by self refresh */
 			ctx->panel_idle_vrefresh = enable ? idle_vrefresh : 0;
-			notify_panel_mode_changed(ctx);
+			notify_panel_mode_changed(ctx, false);
 			if (spanel->auto_mode_vrefresh != idle_vrefresh) {
 				dev_dbg(ctx->dev,
 					"early exit update needed for mode: %s (idle_vrefresh: %d)\n",
@@ -593,7 +593,7 @@ static bool s6e3hc3_set_self_refresh(struct exynos_panel *ctx, bool enable)
 	}
 	EXYNOS_DCS_WRITE_TABLE(ctx, lock_cmd_f0);
 
-	notify_panel_mode_changed(ctx);
+	notify_panel_mode_changed(ctx, false);
 
 	DPU_ATRACE_END(__func__);
 
diff --git a/samsung/panel/panel-samsung-s6e3hc4.c b/samsung/panel/panel-samsung-s6e3hc4.c
index 4340a89..6c68515 100644
--- a/samsung/panel/panel-samsung-s6e3hc4.c
+++ b/samsung/panel/panel-samsung-s6e3hc4.c
@@ -549,7 +549,7 @@ static void s6e3hc4_update_refresh_mode(struct exynos_panel *ctx,
 	ctx->panel_idle_vrefresh = idle_vrefresh;
 	s6e3hc4_update_panel_feat(ctx, vrefresh, false);
 	te2_state_changed(ctx->bl);
-	notify_panel_mode_changed(ctx);
+	notify_panel_mode_changed(ctx, false);
 }
 
 static void s6e3hc4_change_frequency(struct exynos_panel *ctx,
@@ -605,7 +605,7 @@ static bool s6e3hc4_set_self_refresh(struct exynos_panel *ctx, bool enable)
 	if (pmode->exynos_mode.is_lp_mode) {
 		/* set 10Hz while self refresh is active, otherwise clear it */
 		ctx->panel_idle_vrefresh = enable ? 10 : 0;
-		notify_panel_mode_changed(ctx);
+		notify_panel_mode_changed(ctx, true);
 		return false;
 	}