From 8e4468c6de5f11c7ed078599dee21171f8de17af Mon Sep 17 00:00:00 2001
From: Alan <Alan>
Date: Sat, 20 May 2023 14:44:07 +0800
Subject: [PATCH] Optimize: TSC2007 touchscreen add polling method

---
 drivers/input/touchscreen/tsc2007.h      |   6 ++
 drivers/input/touchscreen/tsc2007_core.c | 110 +++++++++++++++++++++--
 2 files changed, 108 insertions(+), 8 deletions(-)

diff --git a/drivers/input/touchscreen/tsc2007.h b/drivers/input/touchscreen/tsc2007.h
index 69b08dd6c8df..5252b6c6daeb 100644
--- a/drivers/input/touchscreen/tsc2007.h
+++ b/drivers/input/touchscreen/tsc2007.h
@@ -66,10 +66,13 @@ struct tsc2007 {
 	u16			model;
 	u16			x_plate_ohms;
 	u16			max_rt;
+	u16			rt_thr;
+	u8			touched;
 	unsigned long		poll_period; /* in jiffies */
 	int			fuzzx;
 	int			fuzzy;
 	int			fuzzz;
+	bool			ignore_nak;
 
 	struct gpio_desc	*gpiod;
 	int			irq;
@@ -81,6 +84,9 @@ struct tsc2007 {
 	void			(*clear_penirq)(void);
 
 	struct mutex		mlock;
+
+	struct timer_list timer;
+	struct work_struct work_i2c_poll;
 };
 
 int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd);
diff --git a/drivers/input/touchscreen/tsc2007_core.c b/drivers/input/touchscreen/tsc2007_core.c
index 21916a30fb76..9e91df8c6bc0 100644
--- a/drivers/input/touchscreen/tsc2007_core.c
+++ b/drivers/input/touchscreen/tsc2007_core.c
@@ -28,6 +28,8 @@
 #include <linux/platform_data/tsc2007.h>
 #include "tsc2007.h"
 
+#define POLL_INTERVAL_MS 17 /* 17ms = 60fps */
+
 int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
 {
 	s32 data;
@@ -172,6 +174,65 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t tsc2007_soft_poll(int irq, void *handle)
+{
+	struct tsc2007 *ts = handle;
+	struct input_dev *input = ts->input;
+	struct ts_event tc;
+	u32 rt;
+
+	if(!ts->stopped) {
+
+		mutex_lock(&ts->mlock);
+		tsc2007_read_values(ts, &tc);
+		mutex_unlock(&ts->mlock);
+
+		rt = tsc2007_calculate_resistance(ts, &tc);
+
+		if (rt == 0 || rt == 256) {
+
+			/*
+				* Sample found inconsistent by debouncing or pressure is
+				* beyond the maximum. Don't report it to user space,
+				* repeat at least once more the measurement.
+				*/
+			dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
+
+		} else {
+
+			if (rt < ts->rt_thr) {
+
+				dev_dbg(&ts->client->dev,
+					"DOWN point(%4d,%4d), resistance (%4u)\n",
+					tc.x, tc.y, rt);
+
+				rt = ts->max_rt - rt;
+
+				input_report_key(input, BTN_TOUCH, 1);
+				input_report_abs(input, ABS_X, tc.y);
+				input_report_abs(input, ABS_Y, 4096 - tc.x);
+				input_report_abs(input, ABS_PRESSURE, rt);
+
+				input_sync(input);
+				ts->touched = 1;
+
+			} else if (ts->touched == 1) {
+
+				dev_dbg(&ts->client->dev, "UP\n");
+
+				input_report_key(input, BTN_TOUCH, 0);
+				input_report_abs(input, ABS_PRESSURE, 0);
+				input_sync(input);
+				ts->touched = 0;
+			}
+		}
+
+
+	}
+
+	return IRQ_HANDLED;
+}
+
 static void tsc2007_stop(struct tsc2007 *ts)
 {
 	ts->stopped = true;
@@ -216,11 +277,32 @@ static int tsc2007_get_pendown_state_gpio(struct device *dev)
 	return gpiod_get_value_cansleep(ts->gpiod);
 }
 
+static void tsc2007_ts_irq_poll_timer(struct timer_list *t)
+{
+	struct tsc2007 *ts = from_timer(ts, t, timer);
+
+	schedule_work(&ts->work_i2c_poll);
+	mod_timer(&ts->timer, jiffies + msecs_to_jiffies(POLL_INTERVAL_MS));
+}
+
+static void tsc2007_ts_work_i2c_poll(struct work_struct *work)
+{
+	struct tsc2007 *ts = container_of(work,
+			struct tsc2007, work_i2c_poll);
+
+	tsc2007_soft_poll(0, ts);
+}
+
 static int tsc2007_probe_properties(struct device *dev, struct tsc2007 *ts)
 {
 	u32 val32;
 	u64 val64;
 
+	ts->ignore_nak = device_property_read_bool(dev, "i2c,ignore-nak");
+
+	if (!device_property_read_u32(dev, "ti,rt-thr", &val32))
+		ts->rt_thr = val32;
+
 	if (!device_property_read_u32(dev, "ti,max-rt", &val32))
 		ts->max_rt = val32;
 	else
@@ -317,6 +399,9 @@ static int tsc2007_probe(struct i2c_client *client)
 	if (!input_dev)
 		return -ENOMEM;
 
+	if (ts->ignore_nak)
+		client->flags |= I2C_M_IGNORE_NAK;
+
 	i2c_set_clientdata(client, ts);
 
 	ts->client = client;
@@ -362,14 +447,23 @@ static int tsc2007_probe(struct i2c_client *client)
 			pdata->init_platform_hw();
 	}
 
-	err = devm_request_threaded_irq(&client->dev, ts->irq,
-					NULL, tsc2007_soft_irq,
-					IRQF_ONESHOT,
-					client->dev.driver->name, ts);
-	if (err) {
-		dev_err(&client->dev, "Failed to request irq %d: %d\n",
-			ts->irq, err);
-		return err;
+	if (ts->gpiod) {
+		err = devm_request_threaded_irq(&client->dev, ts->irq,
+						NULL, tsc2007_soft_irq,
+						IRQF_ONESHOT,
+						client->dev.driver->name, ts);
+		if (err) {
+			dev_err(&client->dev, "Failed to request irq %d: %d\n",
+				ts->irq, err);
+			return err;
+		}
+	} else {
+		INIT_WORK(&ts->work_i2c_poll,
+			  tsc2007_ts_work_i2c_poll);
+		timer_setup(&ts->timer, tsc2007_ts_irq_poll_timer, 0);
+		ts->timer.expires = jiffies +
+					msecs_to_jiffies(POLL_INTERVAL_MS);
+		add_timer(&ts->timer);
 	}
 
 	tsc2007_stop(ts);
-- 
2.34.1