openwrt/target/linux/brcm2708/patches-4.19/950-0364-Input-ili210x-fetch-touchscreen-geometry-from-DT.patch

From 9c823e2ee1ec1b815b8ec29c231b112c5e397202 Mon Sep 17 00:00:00 2001
From: Samuel Hsu <hsu@distec.de>
Date: Mon, 8 Apr 2019 16:42:17 +0200
Subject: [PATCH] Input: ili210x - fetch touchscreen geometry from DT

commit f67cc3e927d8414ad3872e046764534ea1f5db0d upstream

Fetching the geometry from the ILI251x registers seems unreliable and
sometimes returns all zeroes. Add support for fetching the geometry and
axis inversion from DT instead.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/touchscreen/ili210x.c | 321 +++++++++++++++++-----------
 1 file changed, 194 insertions(+), 127 deletions(-)

--- a/drivers/input/touchscreen/ili210x.c
+++ b/drivers/input/touchscreen/ili210x.c
@@ -4,11 +4,15 @@
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
 #include <linux/delay.h>
 #include <linux/workqueue.h>
-#include <linux/input/ili210x.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of_device.h>
+#include <asm/unaligned.h>
 
-#define MAX_TOUCHES		2
+#define ILI210X_TOUCHES		2
+#define ILI251X_TOUCHES		10
 #define DEFAULT_POLL_PERIOD	20
 
 /* Touchscreen commands */
@@ -17,41 +21,32 @@
 #define REG_FIRMWARE_VERSION	0x40
 #define REG_CALIBRATE		0xcc
 
-struct finger {
-	u8 x_low;
-	u8 x_high;
-	u8 y_low;
-	u8 y_high;
-} __packed;
-
-struct touchdata {
-	u8 status;
-	struct finger finger[MAX_TOUCHES];
-} __packed;
-
-struct panel_info {
-	struct finger finger_max;
-	u8 xchannel_num;
-	u8 ychannel_num;
-} __packed;
-
 struct firmware_version {
 	u8 id;
 	u8 major;
 	u8 minor;
 } __packed;
 
+enum ili2xxx_model {
+	MODEL_ILI210X,
+	MODEL_ILI251X,
+};
+
 struct ili210x {
 	struct i2c_client *client;
 	struct input_dev *input;
-	bool (*get_pendown_state)(void);
 	unsigned int poll_period;
 	struct delayed_work dwork;
+	struct gpio_desc *reset_gpio;
+	struct touchscreen_properties prop;
+	enum ili2xxx_model model;
+	unsigned int max_touches;
 };
 
 static int ili210x_read_reg(struct i2c_client *client, u8 reg, void *buf,
 			    size_t len)
 {
+	struct ili210x *priv = i2c_get_clientdata(client);
 	struct i2c_msg msg[2] = {
 		{
 			.addr	= client->addr,
@@ -67,7 +62,38 @@ static int ili210x_read_reg(struct i2c_c
 		}
 	};
 
-	if (i2c_transfer(client->adapter, msg, 2) != 2) {
+	if (priv->model == MODEL_ILI251X) {
+		if (i2c_transfer(client->adapter, msg, 1) != 1) {
+			dev_err(&client->dev, "i2c transfer failed\n");
+			return -EIO;
+		}
+
+		usleep_range(5000, 5500);
+
+		if (i2c_transfer(client->adapter, msg + 1, 1) != 1) {
+			dev_err(&client->dev, "i2c transfer failed\n");
+			return -EIO;
+		}
+	} else {
+		if (i2c_transfer(client->adapter, msg, 2) != 2) {
+			dev_err(&client->dev, "i2c transfer failed\n");
+			return -EIO;
+		}
+	}
+
+	return 0;
+}
+
+static int ili210x_read(struct i2c_client *client, void *buf, size_t len)
+{
+	struct i2c_msg msg = {
+		.addr	= client->addr,
+		.flags	= I2C_M_RD,
+		.len	= len,
+		.buf	= buf,
+	};
+
+	if (i2c_transfer(client->adapter, &msg, 1) != 1) {
 		dev_err(&client->dev, "i2c transfer failed\n");
 		return -EIO;
 	}
@@ -75,42 +101,72 @@ static int ili210x_read_reg(struct i2c_c
 	return 0;
 }
 
-static void ili210x_report_events(struct input_dev *input,
-				  const struct touchdata *touchdata)
+static bool ili210x_touchdata_to_coords(struct ili210x *priv, u8 *touchdata,
+					unsigned int finger,
+					unsigned int *x, unsigned int *y)
 {
-	int i;
-	bool touch;
-	unsigned int x, y;
-	const struct finger *finger;
+	if (finger >= ILI210X_TOUCHES)
+		return false;
 
-	for (i = 0; i < MAX_TOUCHES; i++) {
-		input_mt_slot(input, i);
+	if (touchdata[0] & BIT(finger))
+		return false;
 
-		finger = &touchdata->finger[i];
+	*x = get_unaligned_be16(touchdata + 1 + (finger * 4) + 0);
+	*y = get_unaligned_be16(touchdata + 1 + (finger * 4) + 2);
 
-		touch = touchdata->status & (1 << i);
-		input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
-		if (touch) {
-			x = finger->x_low | (finger->x_high << 8);
-			y = finger->y_low | (finger->y_high << 8);
+	return true;
+}
+
+static bool ili251x_touchdata_to_coords(struct ili210x *priv, u8 *touchdata,
+					unsigned int finger,
+					unsigned int *x, unsigned int *y)
+{
+	if (finger >= ILI251X_TOUCHES)
+		return false;
+
+	*x = get_unaligned_be16(touchdata + 1 + (finger * 5) + 0);
+	if (!(*x & BIT(15)))	/* Touch indication */
+		return false;
+
+	*x &= 0x3fff;
+	*y = get_unaligned_be16(touchdata + 1 + (finger * 5) + 2);
+
+	return true;
+}
+
+static bool ili210x_report_events(struct ili210x *priv, u8 *touchdata)
+{
+	struct input_dev *input = priv->input;
+	int i;
+	bool contact = false, touch = false;
+	unsigned int x = 0, y = 0;
 
-			input_report_abs(input, ABS_MT_POSITION_X, x);
-			input_report_abs(input, ABS_MT_POSITION_Y, y);
+	for (i = 0; i < priv->max_touches; i++) {
+		if (priv->model == MODEL_ILI210X) {
+			touch = ili210x_touchdata_to_coords(priv, touchdata,
+							    i, &x, &y);
+		} else if (priv->model == MODEL_ILI251X) {
+			touch = ili251x_touchdata_to_coords(priv, touchdata,
+							    i, &x, &y);
+			if (touch)
+				contact = true;
 		}
+
+		input_mt_slot(input, i);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
+		if (!touch)
+			continue;
+		touchscreen_report_pos(input, &priv->prop, x, y,
+				       true);
 	}
 
 	input_mt_report_pointer_emulation(input, false);
 	input_sync(input);
-}
 
-static bool get_pendown_state(const struct ili210x *priv)
-{
-	bool state = false;
-
-	if (priv->get_pendown_state)
-		state = priv->get_pendown_state();
+	if (priv->model == MODEL_ILI210X)
+		contact = touchdata[0] & 0xf3;
 
-	return state;
+	return contact;
 }
 
 static void ili210x_work(struct work_struct *work)
@@ -118,20 +174,29 @@ static void ili210x_work(struct work_str
 	struct ili210x *priv = container_of(work, struct ili210x,
 					    dwork.work);
 	struct i2c_client *client = priv->client;
-	struct touchdata touchdata;
-	int error;
+	u8 touchdata[64] = { 0 };
+	bool touch;
+	int error = -EINVAL;
+
+	if (priv->model == MODEL_ILI210X) {
+		error = ili210x_read_reg(client, REG_TOUCHDATA,
+					 touchdata, sizeof(touchdata));
+	} else if (priv->model == MODEL_ILI251X) {
+		error = ili210x_read_reg(client, REG_TOUCHDATA,
+					 touchdata, 31);
+		if (!error && touchdata[0] == 2)
+			error = ili210x_read(client, &touchdata[31], 20);
+	}
 
-	error = ili210x_read_reg(client, REG_TOUCHDATA,
-				 &touchdata, sizeof(touchdata));
 	if (error) {
 		dev_err(&client->dev,
 			"Unable to get touchdata, err = %d\n", error);
 		return;
 	}
 
-	ili210x_report_events(priv->input, &touchdata);
+	touch = ili210x_report_events(priv, touchdata);
 
-	if ((touchdata.status & 0xf3) || get_pendown_state(priv))
+	if (touch)
 		schedule_delayed_work(&priv->dwork,
 				      msecs_to_jiffies(priv->poll_period));
 }
@@ -180,30 +245,76 @@ static const struct attribute_group ili2
 	.attrs = ili210x_attributes,
 };
 
+static void ili210x_power_down(void *data)
+{
+	struct gpio_desc *reset_gpio = data;
+
+	gpiod_set_value_cansleep(reset_gpio, 1);
+}
+
+static void ili210x_cancel_work(void *data)
+{
+	struct ili210x *priv = data;
+
+	cancel_delayed_work_sync(&priv->dwork);
+}
+
 static int ili210x_i2c_probe(struct i2c_client *client,
 				       const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
-	const struct ili210x_platform_data *pdata = dev_get_platdata(dev);
 	struct ili210x *priv;
+	struct gpio_desc *reset_gpio;
 	struct input_dev *input;
-	struct panel_info panel;
 	struct firmware_version firmware;
-	int xmax, ymax;
+	enum ili2xxx_model model;
 	int error;
 
-	dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
+	model = (enum ili2xxx_model)id->driver_data;
 
-	if (!pdata) {
-		dev_err(dev, "No platform data!\n");
-		return -EINVAL;
-	}
+	dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
 
 	if (client->irq <= 0) {
 		dev_err(dev, "No IRQ!\n");
 		return -EINVAL;
 	}
 
+	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(reset_gpio))
+		return PTR_ERR(reset_gpio);
+
+	if (reset_gpio) {
+		error = devm_add_action_or_reset(dev, ili210x_power_down,
+						 reset_gpio);
+		if (error)
+			return error;
+
+		usleep_range(50, 100);
+		gpiod_set_value_cansleep(reset_gpio, 0);
+		msleep(100);
+	}
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
+	priv->client = client;
+	priv->input = input;
+	priv->poll_period = DEFAULT_POLL_PERIOD;
+	INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
+	priv->reset_gpio = reset_gpio;
+	priv->model = model;
+	if (model == MODEL_ILI210X)
+		priv->max_touches = ILI210X_TOUCHES;
+	if (model == MODEL_ILI251X)
+		priv->max_touches = ILI251X_TOUCHES;
+
+	i2c_set_clientdata(client, priv);
+
 	/* Get firmware version */
 	error = ili210x_read_reg(client, REG_FIRMWARE_VERSION,
 				 &firmware, sizeof(firmware));
@@ -213,70 +324,40 @@ static int ili210x_i2c_probe(struct i2c_
 		return error;
 	}
 
-	/* get panel info */
-	error = ili210x_read_reg(client, REG_PANEL_INFO, &panel, sizeof(panel));
-	if (error) {
-		dev_err(dev, "Failed to get panel information, err: %d\n",
-			error);
-		return error;
-	}
-
-	xmax = panel.finger_max.x_low | (panel.finger_max.x_high << 8);
-	ymax = panel.finger_max.y_low | (panel.finger_max.y_high << 8);
-
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	input = input_allocate_device();
-	if (!priv || !input) {
-		error = -ENOMEM;
-		goto err_free_mem;
-	}
-
-	priv->client = client;
-	priv->input = input;
-	priv->get_pendown_state = pdata->get_pendown_state;
-	priv->poll_period = pdata->poll_period ? : DEFAULT_POLL_PERIOD;
-	INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
-
 	/* Setup input device */
 	input->name = "ILI210x Touchscreen";
 	input->id.bustype = BUS_I2C;
 	input->dev.parent = dev;
 
-	__set_bit(EV_SYN, input->evbit);
-	__set_bit(EV_KEY, input->evbit);
-	__set_bit(EV_ABS, input->evbit);
-	__set_bit(BTN_TOUCH, input->keybit);
-
-	/* Single touch */
-	input_set_abs_params(input, ABS_X, 0, xmax, 0, 0);
-	input_set_abs_params(input, ABS_Y, 0, ymax, 0, 0);
-
 	/* Multi touch */
-	input_mt_init_slots(input, MAX_TOUCHES, 0);
-	input_set_abs_params(input, ABS_MT_POSITION_X, 0, xmax, 0, 0);
-	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ymax, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, 0xffff, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 0xffff, 0, 0);
+	touchscreen_parse_properties(input, true, &priv->prop);
+	input_mt_init_slots(input, priv->max_touches, INPUT_MT_DIRECT);
 
-	i2c_set_clientdata(client, priv);
+	error = devm_add_action(dev, ili210x_cancel_work, priv);
+	if (error)
+		return error;
 
-	error = request_irq(client->irq, ili210x_irq, pdata->irq_flags,
-			    client->name, priv);
+	error = devm_request_irq(dev, client->irq, ili210x_irq, 0,
+				 client->name, priv);
 	if (error) {
 		dev_err(dev, "Unable to request touchscreen IRQ, err: %d\n",
 			error);
-		goto err_free_mem;
+		return error;
 	}
 
-	error = sysfs_create_group(&dev->kobj, &ili210x_attr_group);
+	error = devm_device_add_group(dev, &ili210x_attr_group);
 	if (error) {
 		dev_err(dev, "Unable to create sysfs attributes, err: %d\n",
 			error);
-		goto err_free_irq;
+		return error;
 	}
 
 	error = input_register_device(priv->input);
 	if (error) {
 		dev_err(dev, "Cannot register input device, err: %d\n", error);
-		goto err_remove_sysfs;
+		return error;
 	}
 
 	device_init_wakeup(dev, 1);
@@ -286,28 +367,6 @@ static int ili210x_i2c_probe(struct i2c_
 		client->irq, firmware.id, firmware.major, firmware.minor);
 
 	return 0;
-
-err_remove_sysfs:
-	sysfs_remove_group(&dev->kobj, &ili210x_attr_group);
-err_free_irq:
-	free_irq(client->irq, priv);
-err_free_mem:
-	input_free_device(input);
-	kfree(priv);
-	return error;
-}
-
-static int ili210x_i2c_remove(struct i2c_client *client)
-{
-	struct ili210x *priv = i2c_get_clientdata(client);
-
-	sysfs_remove_group(&client->dev.kobj, &ili210x_attr_group);
-	free_irq(priv->client->irq, priv);
-	cancel_delayed_work_sync(&priv->dwork);
-	input_unregister_device(priv->input);
-	kfree(priv);
-
-	return 0;
 }
 
 static int __maybe_unused ili210x_i2c_suspend(struct device *dev)
@@ -334,19 +393,27 @@ static SIMPLE_DEV_PM_OPS(ili210x_i2c_pm,
 			 ili210x_i2c_suspend, ili210x_i2c_resume);
 
 static const struct i2c_device_id ili210x_i2c_id[] = {
-	{ "ili210x", 0 },
+	{ "ili210x", MODEL_ILI210X },
+	{ "ili251x", MODEL_ILI251X },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ili210x_i2c_id);
 
+static const struct of_device_id ili210x_dt_ids[] = {
+	{ .compatible = "ilitek,ili210x", .data = (void *)MODEL_ILI210X },
+	{ .compatible = "ilitek,ili251x", .data = (void *)MODEL_ILI251X },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ili210x_dt_ids);
+
 static struct i2c_driver ili210x_ts_driver = {
 	.driver = {
 		.name = "ili210x_i2c",
 		.pm = &ili210x_i2c_pm,
+		.of_match_table = ili210x_dt_ids,
 	},
 	.id_table = ili210x_i2c_id,
 	.probe = ili210x_i2c_probe,
-	.remove = ili210x_i2c_remove,
 };
 
 module_i2c_driver(ili210x_ts_driver);