drivers/input/touchscreen/egalax_ts.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Driver for EETI eGalax Multiple Touch Controller
  *
  * Copyright (C) 2011 Freescale Semiconductor, Inc.
  *
  * based on max11801_ts.c
  */

 /* EETI eGalax serial touch screen controller is a I2C based multiple
  * touch screen controller, it supports 5 point multiple touch. */

 /* TODO:
   - auto idle mode support
 */

 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/input.h>
 #include <linux/irq.h>
 #include <linux/gpio/consumer.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/bitops.h>
 #include <linux/input/mt.h>

 /*
  * Mouse Mode: some panel may configure the controller to mouse mode,
  * which can only report one point at a given time.
  * This driver will ignore events in this mode.
  */
 #define REPORT_MODE_MOUSE		0x1
 /*
  * Vendor Mode: this mode is used to transfer some vendor specific
  * messages.
  * This driver will ignore events in this mode.
  */
 #define REPORT_MODE_VENDOR		0x3
 /* Multiple Touch Mode */
 #define REPORT_MODE_MTTOUCH		0x4

 #define MAX_SUPPORT_POINTS		5

 #define EVENT_VALID_OFFSET	7
 #define EVENT_VALID_MASK	(0x1 << EVENT_VALID_OFFSET)
 #define EVENT_ID_OFFSET		2
 #define EVENT_ID_MASK		(0xf << EVENT_ID_OFFSET)
 #define EVENT_IN_RANGE		(0x1 << 1)
 #define EVENT_DOWN_UP		(0X1 << 0)

 #define MAX_I2C_DATA_LEN	10

 #define EGALAX_MAX_X	32760
 #define EGALAX_MAX_Y	32760
 #define EGALAX_MAX_TRIES 100

 struct egalax_ts {
 	struct i2c_client		*client;
 	struct input_dev		*input_dev;
 };

 static irqreturn_t egalax_ts_interrupt(int irq, void *dev_id)
 {
 	struct egalax_ts *ts = dev_id;
 	struct input_dev *input_dev = ts->input_dev;
 	struct i2c_client *client = ts->client;
 	u8 buf[MAX_I2C_DATA_LEN];
 	int id, ret, x, y, z;
 	int tries = 0;
 	bool down, valid;
 	u8 state;

 	do {
 		ret = i2c_master_recv(client, buf, MAX_I2C_DATA_LEN);
 	} while (ret == -EAGAIN && tries++ < EGALAX_MAX_TRIES);

 	if (ret < 0)
 		return IRQ_HANDLED;

 	if (buf[0] != REPORT_MODE_MTTOUCH) {
 		/* ignore mouse events and vendor events */
 		return IRQ_HANDLED;
 	}

 	state = buf[1];
 	x = (buf[3] << 8) | buf[2];
 	y = (buf[5] << 8) | buf[4];
 	z = (buf[7] << 8) | buf[6];

 	valid = state & EVENT_VALID_MASK;
 	id = (state & EVENT_ID_MASK) >> EVENT_ID_OFFSET;
 	down = state & EVENT_DOWN_UP;

 	if (!valid || id > MAX_SUPPORT_POINTS) {
 		dev_dbg(&client->dev, "point invalid\n");
 		return IRQ_HANDLED;
 	}

 	input_mt_slot(input_dev, id);
 	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, down);

 	dev_dbg(&client->dev, "%s id:%d x:%d y:%d z:%d",
 		down ? "down" : "up", id, x, y, z);

 	if (down) {
 		input_report_abs(input_dev, ABS_MT_POSITION_X, x);
 		input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
 		input_report_abs(input_dev, ABS_MT_PRESSURE, z);
 	}

 	input_mt_report_pointer_emulation(input_dev, true);
 	input_sync(input_dev);

 	return IRQ_HANDLED;
 }

 /* wake up controller by an falling edge of interrupt gpio.  */
 static int egalax_wake_up_device(struct i2c_client *client)
 {
 	struct gpio_desc *gpio;
 	int ret;

 	/* wake up controller via an falling edge on IRQ gpio. */
 	gpio = gpiod_get(&client->dev, "wakeup", GPIOD_OUT_HIGH);
 	ret = PTR_ERR_OR_ZERO(gpio);
 	if (ret) {
 		if (ret != -EPROBE_DEFER)
 			dev_err(&client->dev,
 				"failed to request wakeup gpio, cannot wake up controller: %d\n",
 				ret);
 		return ret;
 	}

 	/* release the line */
 	gpiod_set_value_cansleep(gpio, 0);

 	/* controller should be woken up, return irq.  */
 	gpiod_direction_input(gpio);
 	gpiod_put(gpio);

 	return 0;
 }

 static int egalax_firmware_version(struct i2c_client *client)
 {
 	static const u8 cmd[MAX_I2C_DATA_LEN] = { 0x03, 0x03, 0xa, 0x01, 0x41 };
 	int ret;

 	ret = i2c_master_send(client, cmd, MAX_I2C_DATA_LEN);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int egalax_ts_probe(struct i2c_client *client)
 {
 	struct egalax_ts *ts;
 	struct input_dev *input_dev;
 	int error;

 	ts = devm_kzalloc(&client->dev, sizeof(struct egalax_ts), GFP_KERNEL);
 	if (!ts) {
 		dev_err(&client->dev, "Failed to allocate memory\n");
 		return -ENOMEM;
 	}

 	input_dev = devm_input_allocate_device(&client->dev);
 	if (!input_dev) {
 		dev_err(&client->dev, "Failed to allocate memory\n");
 		return -ENOMEM;
 	}

 	ts->client = client;
 	ts->input_dev = input_dev;

 	/* controller may be in sleep, wake it up. */
 	error = egalax_wake_up_device(client);
 	if (error)
 		return error;

 	error = egalax_firmware_version(client);
 	if (error < 0) {
 		dev_err(&client->dev, "Failed to read firmware version\n");
 		return error;
 	}

 	input_dev->name = "EETI eGalax Touch Screen";
 	input_dev->id.bustype = BUS_I2C;

 	__set_bit(EV_ABS, input_dev->evbit);
 	__set_bit(EV_KEY, input_dev->evbit);
 	__set_bit(BTN_TOUCH, input_dev->keybit);

 	input_set_abs_params(input_dev, ABS_X, 0, EGALAX_MAX_X, 0, 0);
 	input_set_abs_params(input_dev, ABS_Y, 0, EGALAX_MAX_Y, 0, 0);
 	input_set_abs_params(input_dev,
 			     ABS_MT_POSITION_X, 0, EGALAX_MAX_X, 0, 0);
 	input_set_abs_params(input_dev,
 			     ABS_MT_POSITION_Y, 0, EGALAX_MAX_Y, 0, 0);
 	input_mt_init_slots(input_dev, MAX_SUPPORT_POINTS, 0);

 	error = devm_request_threaded_irq(&client->dev, client->irq,
 					  NULL, egalax_ts_interrupt,
 					  IRQF_ONESHOT, "egalax_ts", ts);
 	if (error < 0) {
 		dev_err(&client->dev, "Failed to register interrupt\n");
 		return error;
 	}

 	error = input_register_device(ts->input_dev);
 	if (error)
 		return error;

 	return 0;
 }

 static const struct i2c_device_id egalax_ts_id[] = {
 	{ "egalax_ts", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, egalax_ts_id);

 static int egalax_ts_suspend(struct device *dev)
 {
 	static const u8 suspend_cmd[MAX_I2C_DATA_LEN] = {
 		0x3, 0x6, 0xa, 0x3, 0x36, 0x3f, 0x2, 0, 0, 0
 	};
 	struct i2c_client *client = to_i2c_client(dev);
 	int ret;

 	if (device_may_wakeup(dev))
 		return enable_irq_wake(client->irq);

 	ret = i2c_master_send(client, suspend_cmd, MAX_I2C_DATA_LEN);
 	return ret > 0 ? 0 : ret;
 }

 static int egalax_ts_resume(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);

 	if (device_may_wakeup(dev))
 		return disable_irq_wake(client->irq);

 	return egalax_wake_up_device(client);
 }

 static DEFINE_SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops,
 				egalax_ts_suspend, egalax_ts_resume);

 static const struct of_device_id egalax_ts_dt_ids[] = {
 	{ .compatible = "eeti,egalax_ts" },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, egalax_ts_dt_ids);

 static struct i2c_driver egalax_ts_driver = {
 	.driver = {
 		.name	= "egalax_ts",
 		.pm	= pm_sleep_ptr(&egalax_ts_pm_ops),
 		.of_match_table	= egalax_ts_dt_ids,
 	},
 	.id_table	= egalax_ts_id,
 	.probe		= egalax_ts_probe,
 };

 module_i2c_driver(egalax_ts_driver);

 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
 MODULE_DESCRIPTION("Touchscreen driver for EETI eGalax touch controller");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Driver for EETI eGalax Multiple Touch Controller
	*
	* Copyright (C) 2011 Freescale Semiconductor, Inc.
	*
	* based on max11801_ts.c
	*/

	/* EETI eGalax serial touch screen controller is a I2C based multiple
	* touch screen controller, it supports 5 point multiple touch. */

	/* TODO:
	- auto idle mode support
	*/

	#include <linux/err.h>
	#include <linux/module.h>
	#include <linux/i2c.h>
	#include <linux/interrupt.h>
	#include <linux/input.h>
	#include <linux/irq.h>
	#include <linux/gpio/consumer.h>
	#include <linux/delay.h>
	#include <linux/slab.h>
	#include <linux/bitops.h>
	#include <linux/input/mt.h>

	/*
	* Mouse Mode: some panel may configure the controller to mouse mode,
	* which can only report one point at a given time.
	* This driver will ignore events in this mode.
	*/
	#define REPORT_MODE_MOUSE 0x1
	/*
	* Vendor Mode: this mode is used to transfer some vendor specific
	* messages.
	* This driver will ignore events in this mode.
	*/
	#define REPORT_MODE_VENDOR 0x3
	/* Multiple Touch Mode */
	#define REPORT_MODE_MTTOUCH 0x4

	#define MAX_SUPPORT_POINTS 5

	#define EVENT_VALID_OFFSET 7
	#define EVENT_VALID_MASK (0x1 << EVENT_VALID_OFFSET)
	#define EVENT_ID_OFFSET 2
	#define EVENT_ID_MASK (0xf << EVENT_ID_OFFSET)
	#define EVENT_IN_RANGE (0x1 << 1)
	#define EVENT_DOWN_UP (0X1 << 0)

	#define MAX_I2C_DATA_LEN 10

	#define EGALAX_MAX_X 32760
	#define EGALAX_MAX_Y 32760
	#define EGALAX_MAX_TRIES 100

	struct egalax_ts {
	struct i2c_client *client;
	struct input_dev *input_dev;
	};

	static irqreturn_t egalax_ts_interrupt(int irq, void *dev_id)
	{
	struct egalax_ts *ts = dev_id;
	struct input_dev *input_dev = ts->input_dev;
	struct i2c_client *client = ts->client;
	u8 buf[MAX_I2C_DATA_LEN];
	int id, ret, x, y, z;
	int tries = 0;
	bool down, valid;
	u8 state;

	do {
	ret = i2c_master_recv(client, buf, MAX_I2C_DATA_LEN);
	} while (ret == -EAGAIN && tries++ < EGALAX_MAX_TRIES);

	if (ret < 0)
	return IRQ_HANDLED;

	if (buf[0] != REPORT_MODE_MTTOUCH) {
	/* ignore mouse events and vendor events */
	return IRQ_HANDLED;
	}

	state = buf[1];
	x = (buf[3] << 8) \| buf[2];
	y = (buf[5] << 8) \| buf[4];
	z = (buf[7] << 8) \| buf[6];

	valid = state & EVENT_VALID_MASK;
	id = (state & EVENT_ID_MASK) >> EVENT_ID_OFFSET;
	down = state & EVENT_DOWN_UP;

	if (!valid \|\| id > MAX_SUPPORT_POINTS) {
	dev_dbg(&client->dev, "point invalid\n");
	return IRQ_HANDLED;
	}

	input_mt_slot(input_dev, id);
	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, down);

	dev_dbg(&client->dev, "%s id:%d x:%d y:%d z:%d",
	down ? "down" : "up", id, x, y, z);

	if (down) {
	input_report_abs(input_dev, ABS_MT_POSITION_X, x);
	input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
	input_report_abs(input_dev, ABS_MT_PRESSURE, z);
	}

	input_mt_report_pointer_emulation(input_dev, true);
	input_sync(input_dev);

	return IRQ_HANDLED;
	}

	/* wake up controller by an falling edge of interrupt gpio. */
	static int egalax_wake_up_device(struct i2c_client *client)
	{
	struct gpio_desc *gpio;
	int ret;

	/* wake up controller via an falling edge on IRQ gpio. */
	gpio = gpiod_get(&client->dev, "wakeup", GPIOD_OUT_HIGH);
	ret = PTR_ERR_OR_ZERO(gpio);
	if (ret) {
	if (ret != -EPROBE_DEFER)
	dev_err(&client->dev,
	"failed to request wakeup gpio, cannot wake up controller: %d\n",
	ret);
	return ret;
	}

	/* release the line */
	gpiod_set_value_cansleep(gpio, 0);

	/* controller should be woken up, return irq. */
	gpiod_direction_input(gpio);
	gpiod_put(gpio);

	return 0;
	}

	static int egalax_firmware_version(struct i2c_client *client)
	{
	static const u8 cmd[MAX_I2C_DATA_LEN] = { 0x03, 0x03, 0xa, 0x01, 0x41 };
	int ret;

	ret = i2c_master_send(client, cmd, MAX_I2C_DATA_LEN);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int egalax_ts_probe(struct i2c_client *client)
	{
	struct egalax_ts *ts;
	struct input_dev *input_dev;
	int error;

	ts = devm_kzalloc(&client->dev, sizeof(struct egalax_ts), GFP_KERNEL);
	if (!ts) {
	dev_err(&client->dev, "Failed to allocate memory\n");
	return -ENOMEM;
	}

	input_dev = devm_input_allocate_device(&client->dev);
	if (!input_dev) {
	dev_err(&client->dev, "Failed to allocate memory\n");
	return -ENOMEM;
	}

	ts->client = client;
	ts->input_dev = input_dev;

	/* controller may be in sleep, wake it up. */
	error = egalax_wake_up_device(client);
	if (error)
	return error;

	error = egalax_firmware_version(client);
	if (error < 0) {
	dev_err(&client->dev, "Failed to read firmware version\n");
	return error;
	}

	input_dev->name = "EETI eGalax Touch Screen";
	input_dev->id.bustype = BUS_I2C;

	__set_bit(EV_ABS, input_dev->evbit);
	__set_bit(EV_KEY, input_dev->evbit);
	__set_bit(BTN_TOUCH, input_dev->keybit);

	input_set_abs_params(input_dev, ABS_X, 0, EGALAX_MAX_X, 0, 0);
	input_set_abs_params(input_dev, ABS_Y, 0, EGALAX_MAX_Y, 0, 0);
	input_set_abs_params(input_dev,
	ABS_MT_POSITION_X, 0, EGALAX_MAX_X, 0, 0);
	input_set_abs_params(input_dev,
	ABS_MT_POSITION_Y, 0, EGALAX_MAX_Y, 0, 0);
	input_mt_init_slots(input_dev, MAX_SUPPORT_POINTS, 0);

	error = devm_request_threaded_irq(&client->dev, client->irq,
	NULL, egalax_ts_interrupt,
	IRQF_ONESHOT, "egalax_ts", ts);
	if (error < 0) {
	dev_err(&client->dev, "Failed to register interrupt\n");
	return error;
	}

	error = input_register_device(ts->input_dev);
	if (error)
	return error;

	return 0;
	}

	static const struct i2c_device_id egalax_ts_id[] = {
	{ "egalax_ts", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, egalax_ts_id);

	static int egalax_ts_suspend(struct device *dev)
	{
	static const u8 suspend_cmd[MAX_I2C_DATA_LEN] = {
	0x3, 0x6, 0xa, 0x3, 0x36, 0x3f, 0x2, 0, 0, 0
	};
	struct i2c_client *client = to_i2c_client(dev);
	int ret;

	if (device_may_wakeup(dev))
	return enable_irq_wake(client->irq);

	ret = i2c_master_send(client, suspend_cmd, MAX_I2C_DATA_LEN);
	return ret > 0 ? 0 : ret;
	}

	static int egalax_ts_resume(struct device *dev)
	{
	struct i2c_client *client = to_i2c_client(dev);

	if (device_may_wakeup(dev))
	return disable_irq_wake(client->irq);

	return egalax_wake_up_device(client);
	}

	static DEFINE_SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops,
	egalax_ts_suspend, egalax_ts_resume);

	static const struct of_device_id egalax_ts_dt_ids[] = {
	{ .compatible = "eeti,egalax_ts" },
	{ /* sentinel */ }
	};
	MODULE_DEVICE_TABLE(of, egalax_ts_dt_ids);

	static struct i2c_driver egalax_ts_driver = {
	.driver = {
	.name = "egalax_ts",
	.pm = pm_sleep_ptr(&egalax_ts_pm_ops),
	.of_match_table = egalax_ts_dt_ids,
	},
	.id_table = egalax_ts_id,
	.probe = egalax_ts_probe,
	};

	module_i2c_driver(egalax_ts_driver);

	MODULE_AUTHOR("Freescale Semiconductor, Inc.");
	MODULE_DESCRIPTION("Touchscreen driver for EETI eGalax touch controller");
	MODULE_LICENSE("GPL");