pat9126: Use DRM suspend/resume notifiers

Integrate DRM suspend/resume with crown low power/normal modes. These
replace the framebuffer hooks that no longer exist in 5.4.

Bug: 254115794
Signed-off-by: Amit Bhanagay <amitbhanagay@google.com>
Change-Id: I48355ac8d40274e88938b81ab6dd4edf03ccfd37

1 files changed, 91 insertions, 32 deletions

diff --git a/ots_pat9126/pat9126.c b/ots_pat9126/pat9126.c
index ba78f58..288e8f0 100644
--- a/ots_pat9126/pat9126.c
+++ b/ots_pat9126/pat9126.c
@@ -14,17 +14,16 @@
 #include <linux/delay.h>
 #include <linux/regulator/consumer.h>
 #include "pat9126.h"
-#include <linux/fb.h>
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/mm.h>
 #include <asm/uaccess.h>
-
 #include <linux/notifier.h>
 #include <linux/reboot.h>
-#include<linux/time.h>
+#include <linux/time.h>
 #include <linux/rtc.h>
 #include <linux/string.h>
+#include <drm/drm_panel.h>
 
 struct pixart_pat9126_data {
 	struct i2c_client *client;
@@ -46,7 +45,7 @@ struct pixart_pat9126_data {
 	struct workqueue_struct *workqueue;
 	struct delayed_work polling_work;
 	struct delayed_work resume_work;
-	struct notifier_block fb_notif;
+	struct notifier_block drm_panel_notif;
 	struct mutex mtx;
 	struct regulator *vdd_supply;
 	struct regulator *vld_supply;
@@ -66,7 +65,11 @@ struct rw_reg_info {
 struct rw_reg_info pat9126_reg_info;
 
 /* Declaration of suspend and resume functions */
-static int pat9126_fb_callback(struct notifier_block *nb, unsigned long type, void *arg);
+static struct drm_panel *active_panel;
+static int pat9126_drm_panel_notifier_callback(struct notifier_block *self,
+						unsigned long event,
+						void *data);
+
 static int pat9126_display_suspend(struct device *dev);
 static int pat9126_display_resume(struct device *dev);
 
@@ -822,6 +825,31 @@ static int pat9126_parse_dt(struct device *dev,
 	return 0;
 }
 
+static int pat9126_check_dt(struct device_node *np)
+{
+	int i;
+	int count;
+	struct device_node *node;
+	struct drm_panel *panel;
+
+	count = of_count_phandle_with_args(np, "panel", NULL);
+	if (count <= 0) {
+		return 0;
+	}
+
+	for (i = 0; i < count; i++) {
+		node = of_parse_phandle(np, "panel", i);
+		panel = of_drm_find_panel(node);
+		of_node_put(node);
+		if (!IS_ERR(panel)) {
+			active_panel = panel;
+			return 0;
+		}
+	}
+
+	return PTR_ERR(panel);
+}
+
 static int pat9126_i2c_probe(struct i2c_client *client,
 		const struct i2c_device_id *id)
 {
@@ -830,6 +858,17 @@ static int pat9126_i2c_probe(struct i2c_client *client,
 	struct input_dev *input;
 	struct device *dev = &client->dev;
 
+	struct device_node *dp = NULL;
+	dp = client->dev.of_node;
+
+	ret = pat9126_check_dt(dp);
+	if (ret) {
+		if (ret == -EPROBE_DEFER) {
+			return -EPROBE_DEFER;
+		}
+		return -ENODEV;
+	}
+
 	ret = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE);
 	if (ret < 0) {
 		dev_err(dev, "I2C not supported\n");
@@ -896,13 +935,15 @@ static int pat9126_i2c_probe(struct i2c_client *client,
 
 	mutex_init(&data->mtx);
 	data->state = PAT9126_STATE_ON;
-	data->display_mode = FB_BLANK_UNBLANK;
-
-	data->fb_notif.notifier_call = pat9126_fb_callback;
-	ret = fb_register_client(&data->fb_notif);
-
-	if (ret) {
-		pr_err("[PAT9126]: Failed to register FB callback\n");
+	data->display_mode = DRM_PANEL_BLANK_UNBLANK;
+	data->drm_panel_notif.notifier_call = pat9126_drm_panel_notifier_callback;
+
+	if (active_panel) {
+		ret = drm_panel_notifier_register(active_panel, &data->drm_panel_notif);
+		if (ret) {
+			dev_err(dev, "register drm_panel_notifier failed, errno:%d\n", ret);
+			goto err_regulators;
+		}
 	}
 
 	INIT_DELAYED_WORK(&data->polling_work, pat9126_work_handler);
@@ -938,41 +979,59 @@ err_regulators:
 
 static int pat9126_i2c_remove(struct i2c_client *client)
 {
+	int ret = 0;
+	struct device *dev = &client->dev;
 	struct pixart_pat9126_data *data = i2c_get_clientdata(client);
 
+	dev_dbg(dev, "%s\n", __func__);
+	if (data) {
+		if (active_panel) {
+			ret = drm_panel_notifier_unregister(active_panel,
+					&data->drm_panel_notif);
+			if (ret) {
+				dev_dbg(dev, "[PAT9126]: unregister "
+					"drm_panel_notifier failed, "
+					"errno:%d\n", ret);
+			}
+		}
+	}
 	pat9126_disable_regulators(data);
 
-	return 0;
+	return ret;
 }
 
-static int pat9126_fb_callback(struct notifier_block *nb, unsigned long type, void *arg) {
-	struct fb_event *event_data = arg;
+static int pat9126_drm_panel_notifier_callback(struct notifier_block *nb,
+						unsigned long event,
+						void *arg)
+{
+	struct drm_panel_notifier *evdata = arg;
+	int *blank;
 	struct pixart_pat9126_data *data =
-		container_of(nb, struct pixart_pat9126_data, fb_notif);
-	struct device *dev = &data->client->dev;
-	int *blank_ptr = event_data->data;
-	int new_mode;
+		container_of(nb, struct pixart_pat9126_data, drm_panel_notif);
 
-	if (type != FB_EVENT_BLANK) {
+	if (!evdata) {
 		return 0;
 	}
 
-	if (!blank_ptr) {
-		pr_warn("[PAT9126] 'blank' is NULL\n");
+	if (!(event == DRM_PANEL_EARLY_EVENT_BLANK ||
+		event == DRM_PANEL_EVENT_BLANK)) {
 		return 0;
 	}
 
-	new_mode = *blank_ptr;
-
-	if (new_mode == FB_BLANK_UNBLANK &&
-	    data->display_mode != FB_BLANK_UNBLANK) {
-		pat9126_display_resume(dev);
-	} else if (new_mode != FB_BLANK_UNBLANK &&
-	           data->display_mode == FB_BLANK_UNBLANK) {
-		pat9126_display_suspend(dev);
-    }
+	if (evdata->data && data) {
+		blank = evdata->data;
+		if (event == DRM_PANEL_EARLY_EVENT_BLANK) {
+			if ((*blank == DRM_PANEL_BLANK_POWERDOWN) ||
+			    (*blank == DRM_PANEL_BLANK_LP)) {
+				pat9126_display_suspend(&data->client->dev);
+			}
+		} else if (event == DRM_PANEL_EVENT_BLANK) {
+			if (*blank == DRM_PANEL_BLANK_UNBLANK) {
+				pat9126_display_resume(&data->client->dev);
+			}
+		}
+	}
 
-	data->display_mode = new_mode;
 	return 0;
 }