drivers/input/touchscreen/ft6236.c - kernel/bruno - Git at Google

 /*
  * FocalTech FT6236 TouchScreen driver.
  *
  * Copyright (c) 2010  Focal tech Ltd.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
  * may be copied, distributed, and modified under those terms.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/property.h>

 #define FT6236_MAX_TOUCH_POINTS		2

 #define FT6236_REG_TH_GROUP		0x80
 #define FT6236_REG_PERIODACTIVE		0x88
 #define FT6236_REG_LIB_VER_H		0xa1
 #define FT6236_REG_LIB_VER_L		0xa2
 #define FT6236_REG_CIPHER		0xa3
 #define FT6236_REG_FIRMID		0xa6
 #define FT6236_REG_FOCALTECH_ID		0xa8
 #define FT6236_REG_RELEASE_CODE_ID	0xaf

 #define FT6236_EVENT_PRESS_DOWN		0
 #define FT6236_EVENT_LIFT_UP		1
 #define FT6236_EVENT_CONTACT		2
 #define FT6236_EVENT_NO_EVENT		3

 struct ft6236_data {
 	struct i2c_client *client;
 	struct input_dev *input;
 	struct gpio_desc *reset_gpio;
 	u32 max_x;
 	u32 max_y;
 	bool invert_x;
 	bool invert_y;
 	bool swap_xy;
 };

 /*
  * This struct is a touchpoint as stored in hardware.  Note that the id,
  * as well as the event, are stored in the upper nybble of the hi byte.
  */
 struct ft6236_touchpoint {
 	union {
 		u8 xhi;
 		u8 event;
 	};
 	u8 xlo;
 	union {
 		u8 yhi;
 		u8 id;
 	};
 	u8 ylo;
 	u8 weight;
 	u8 misc;
 } __packed;

 /* This packet represents the register map as read from offset 0 */
 struct ft6236_packet {
 	u8 dev_mode;
 	u8 gest_id;
 	u8 touches;
 	struct ft6236_touchpoint points[FT6236_MAX_TOUCH_POINTS];
 } __packed;

 static int ft6236_read(struct i2c_client *client, u8 reg, u8 len, void *data)
 {
 	int error;

 	error = i2c_smbus_read_i2c_block_data(client, reg, len, data);
 	if (error < 0)
 		return error;

 	if (error != len)
 		return -EIO;

 	return 0;
 }

 static irqreturn_t ft6236_interrupt(int irq, void *dev_id)
 {
 	struct ft6236_data *ft6236 = dev_id;
 	struct device *dev = &ft6236->client->dev;
 	struct input_dev *input = ft6236->input;
 	struct ft6236_packet buf;
 	u8 touches;
 	int i, error;

 	error = ft6236_read(ft6236->client, 0, sizeof(buf), &buf);
 	if (error) {
 		dev_err(dev, "read touchdata failed %d\n", error);
 		return IRQ_HANDLED;
 	}

 	touches = buf.touches & 0xf;
 	if (touches > FT6236_MAX_TOUCH_POINTS) {
 		dev_dbg(dev,
 			"%d touch points reported, only %d are supported\n",
 			touches, FT6236_MAX_TOUCH_POINTS);
 		touches = FT6236_MAX_TOUCH_POINTS;
 	}

 	for (i = 0; i < touches; i++) {
 		struct ft6236_touchpoint *point = &buf.points[i];
 		u16 x = ((point->xhi & 0xf) << 8) | buf.points[i].xlo;
 		u16 y = ((point->yhi & 0xf) << 8) | buf.points[i].ylo;
 		u8 event = point->event >> 6;
 		u8 id = point->id >> 4;
 		bool act = (event == FT6236_EVENT_PRESS_DOWN ||
 			    event == FT6236_EVENT_CONTACT);

 		input_mt_slot(input, id);
 		input_mt_report_slot_state(input, MT_TOOL_FINGER, act);
 		if (!act)
 			continue;

 		if (ft6236->invert_x)
 			x = ft6236->max_x - x;

 		if (ft6236->invert_y)
 			y = ft6236->max_y - y;

 		if (ft6236->swap_xy) {
 			input_report_abs(input, ABS_MT_POSITION_X, y);
 			input_report_abs(input, ABS_MT_POSITION_Y, x);
 		} else {
 			input_report_abs(input, ABS_MT_POSITION_X, x);
 			input_report_abs(input, ABS_MT_POSITION_Y, y);
 		}
 	}

 	input_mt_sync_frame(input);
 	input_sync(input);

 	return IRQ_HANDLED;
 }

 static u8 ft6236_debug_read_byte(struct ft6236_data *ft6236, u8 reg)
 {
 	struct i2c_client *client = ft6236->client;
 	u8 val = 0;
 	int error;

 	error = ft6236_read(client, reg, 1, &val);
 	if (error)
 		dev_dbg(&client->dev,
 			"error reading register 0x%02x: %d\n", reg, error);

 	return val;
 }

 static void ft6236_debug_info(struct ft6236_data *ft6236)
 {
 	struct device *dev = &ft6236->client->dev;

 	dev_dbg(dev, "Touch threshold is %d\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_TH_GROUP) * 4);
 	dev_dbg(dev, "Report rate is %dHz\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_PERIODACTIVE) * 10);
 	dev_dbg(dev, "Firmware library version 0x%02x%02x\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_LIB_VER_H),
 		ft6236_debug_read_byte(ft6236, FT6236_REG_LIB_VER_L));
 	dev_dbg(dev, "Firmware version 0x%02x\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_FIRMID));
 	dev_dbg(dev, "Chip vendor ID 0x%02x\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_CIPHER));
 	dev_dbg(dev, "CTPM vendor ID 0x%02x\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_FOCALTECH_ID));
 	dev_dbg(dev, "Release code version 0x%02x\n",
 		ft6236_debug_read_byte(ft6236, FT6236_REG_RELEASE_CODE_ID));
 }

 static void ft6236_reset(struct ft6236_data *ft6236)
 {
 	if (!ft6236->reset_gpio)
 		return;

 	gpiod_set_value_cansleep(ft6236->reset_gpio, 1);
 	usleep_range(5000, 20000);
 	gpiod_set_value_cansleep(ft6236->reset_gpio, 0);
 	msleep(300);
 }

 static int ft6236_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
 	struct ft6236_data *ft6236;
 	struct input_dev *input;
 	u32 fuzz_x = 0, fuzz_y = 0;
 	u8 val;
 	int error;

 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 		return -ENXIO;

 	if (!client->irq) {
 		dev_err(dev, "irq is missing\n");
 		return -EINVAL;
 	}

 	ft6236 = devm_kzalloc(dev, sizeof(*ft6236), GFP_KERNEL);
 	if (!ft6236)
 		return -ENOMEM;

 	ft6236->client = client;
 	ft6236->reset_gpio = devm_gpiod_get_optional(dev, "reset",
 						     GPIOD_OUT_LOW);
 	if (IS_ERR(ft6236->reset_gpio)) {
 		error = PTR_ERR(ft6236->reset_gpio);
 		if (error != -EPROBE_DEFER)
 			dev_err(dev, "error getting reset gpio: %d\n", error);
 		return error;
 	}

 	ft6236_reset(ft6236);

 	/* verify that the controller is present */
 	error = ft6236_read(client, 0x00, 1, &val);
 	if (error) {
 		dev_err(dev, "failed to read from controller: %d\n", error);
 		return error;
 	}

 	ft6236_debug_info(ft6236);

 	input = devm_input_allocate_device(dev);
 	if (!input)
 		return -ENOMEM;

 	ft6236->input = input;
 	input->name = client->name;
 	input->id.bustype = BUS_I2C;

 	if (device_property_read_u32(dev, "touchscreen-size-x",
 				     &ft6236->max_x) ||
 	    device_property_read_u32(dev, "touchscreen-size-y",
 				     &ft6236->max_y)) {
 		dev_err(dev, "touchscreen-size-x and/or -y missing\n");
 		return -EINVAL;
 	}

 	device_property_read_u32(dev, "touchscreen-fuzz-x", &fuzz_x);
 	device_property_read_u32(dev, "touchscreen-fuzz-y", &fuzz_y);
 	ft6236->invert_x = device_property_read_bool(dev,
 						     "touchscreen-inverted-x");
 	ft6236->invert_y = device_property_read_bool(dev,
 						     "touchscreen-inverted-y");
 	ft6236->swap_xy = device_property_read_bool(dev,
 						    "touchscreen-swapped-x-y");

 	if (ft6236->swap_xy) {
 		input_set_abs_params(input, ABS_MT_POSITION_X, 0,
 				     ft6236->max_y, fuzz_y, 0);
 		input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
 				     ft6236->max_x, fuzz_x, 0);
 	} else {
 		input_set_abs_params(input, ABS_MT_POSITION_X, 0,
 				     ft6236->max_x, fuzz_x, 0);
 		input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
 				     ft6236->max_y, fuzz_y, 0);
 	}

 	error = input_mt_init_slots(input, FT6236_MAX_TOUCH_POINTS,
 				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 	if (error)
 		return error;

 	error = devm_request_threaded_irq(dev, client->irq, NULL,
 					  ft6236_interrupt, IRQF_ONESHOT,
 					  client->name, ft6236);
 	if (error) {
 		dev_err(dev, "request irq %d failed: %d\n", client->irq, error);
 		return error;
 	}

 	error = input_register_device(input);
 	if (error) {
 		dev_err(dev, "failed to register input device: %d\n", error);
 		return error;
 	}

 	return 0;
 }

 #ifdef CONFIG_OF
 static const struct of_device_id ft6236_of_match[] = {
 	{ .compatible = "focaltech,ft6236", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ft6236_of_match);
 #endif

 static const struct i2c_device_id ft6236_id[] = {
 	{ "ft6236", },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ft6236_id);

 static struct i2c_driver ft6236_driver = {
 	.driver = {
 		.name = "ft6236",
 		.of_match_table = of_match_ptr(ft6236_of_match),
 	},
 	.probe = ft6236_probe,
 	.id_table = ft6236_id,
 };
 module_i2c_driver(ft6236_driver);

 MODULE_AUTHOR("Sean Cross <xobs@kosagi.com>");
 MODULE_AUTHOR("Noralf Trønnes <noralf@tronnes.org>");
 MODULE_DESCRIPTION("FocalTech FT6236 TouchScreen driver");
 MODULE_LICENSE("GPL v2");
	/*
	* FocalTech FT6236 TouchScreen driver.
	*
	* Copyright (c) 2010 Focal tech Ltd.
	*
	* This software is licensed under the terms of the GNU General Public
	* License version 2, as published by the Free Software Foundation, and
	* may be copied, distributed, and modified under those terms.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/delay.h>
	#include <linux/gpio/consumer.h>
	#include <linux/i2c.h>
	#include <linux/input.h>
	#include <linux/input/mt.h>
	#include <linux/interrupt.h>
	#include <linux/module.h>
	#include <linux/property.h>

	#define FT6236_MAX_TOUCH_POINTS 2

	#define FT6236_REG_TH_GROUP 0x80
	#define FT6236_REG_PERIODACTIVE 0x88
	#define FT6236_REG_LIB_VER_H 0xa1
	#define FT6236_REG_LIB_VER_L 0xa2
	#define FT6236_REG_CIPHER 0xa3
	#define FT6236_REG_FIRMID 0xa6
	#define FT6236_REG_FOCALTECH_ID 0xa8
	#define FT6236_REG_RELEASE_CODE_ID 0xaf

	#define FT6236_EVENT_PRESS_DOWN 0
	#define FT6236_EVENT_LIFT_UP 1
	#define FT6236_EVENT_CONTACT 2
	#define FT6236_EVENT_NO_EVENT 3

	struct ft6236_data {
	struct i2c_client *client;
	struct input_dev *input;
	struct gpio_desc *reset_gpio;
	u32 max_x;
	u32 max_y;
	bool invert_x;
	bool invert_y;
	bool swap_xy;
	};

	/*
	* This struct is a touchpoint as stored in hardware. Note that the id,
	* as well as the event, are stored in the upper nybble of the hi byte.
	*/
	struct ft6236_touchpoint {
	union {
	u8 xhi;
	u8 event;
	};
	u8 xlo;
	union {
	u8 yhi;
	u8 id;
	};
	u8 ylo;
	u8 weight;
	u8 misc;
	} __packed;

	/* This packet represents the register map as read from offset 0 */
	struct ft6236_packet {
	u8 dev_mode;
	u8 gest_id;
	u8 touches;
	struct ft6236_touchpoint points[FT6236_MAX_TOUCH_POINTS];
	} __packed;

	static int ft6236_read(struct i2c_client client, u8 reg, u8 len, void data)
	{
	int error;

	error = i2c_smbus_read_i2c_block_data(client, reg, len, data);
	if (error < 0)
	return error;

	if (error != len)
	return -EIO;

	return 0;
	}

	static irqreturn_t ft6236_interrupt(int irq, void *dev_id)
	{
	struct ft6236_data *ft6236 = dev_id;
	struct device *dev = &ft6236->client->dev;
	struct input_dev *input = ft6236->input;
	struct ft6236_packet buf;
	u8 touches;
	int i, error;

	error = ft6236_read(ft6236->client, 0, sizeof(buf), &buf);
	if (error) {
	dev_err(dev, "read touchdata failed %d\n", error);
	return IRQ_HANDLED;
	}

	touches = buf.touches & 0xf;
	if (touches > FT6236_MAX_TOUCH_POINTS) {
	dev_dbg(dev,
	"%d touch points reported, only %d are supported\n",
	touches, FT6236_MAX_TOUCH_POINTS);
	touches = FT6236_MAX_TOUCH_POINTS;
	}

	for (i = 0; i < touches; i++) {
	struct ft6236_touchpoint *point = &buf.points[i];
	u16 x = ((point->xhi & 0xf) << 8) \| buf.points[i].xlo;
	u16 y = ((point->yhi & 0xf) << 8) \| buf.points[i].ylo;
	u8 event = point->event >> 6;
	u8 id = point->id >> 4;
	bool act = (event == FT6236_EVENT_PRESS_DOWN \|\|
	event == FT6236_EVENT_CONTACT);

	input_mt_slot(input, id);
	input_mt_report_slot_state(input, MT_TOOL_FINGER, act);
	if (!act)
	continue;

	if (ft6236->invert_x)
	x = ft6236->max_x - x;

	if (ft6236->invert_y)
	y = ft6236->max_y - y;

	if (ft6236->swap_xy) {
	input_report_abs(input, ABS_MT_POSITION_X, y);
	input_report_abs(input, ABS_MT_POSITION_Y, x);
	} else {
	input_report_abs(input, ABS_MT_POSITION_X, x);
	input_report_abs(input, ABS_MT_POSITION_Y, y);
	}
	}

	input_mt_sync_frame(input);
	input_sync(input);

	return IRQ_HANDLED;
	}

	static u8 ft6236_debug_read_byte(struct ft6236_data *ft6236, u8 reg)
	{
	struct i2c_client *client = ft6236->client;
	u8 val = 0;
	int error;

	error = ft6236_read(client, reg, 1, &val);
	if (error)
	dev_dbg(&client->dev,
	"error reading register 0x%02x: %d\n", reg, error);

	return val;
	}

	static void ft6236_debug_info(struct ft6236_data *ft6236)
	{
	struct device *dev = &ft6236->client->dev;

	dev_dbg(dev, "Touch threshold is %d\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_TH_GROUP) * 4);
	dev_dbg(dev, "Report rate is %dHz\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_PERIODACTIVE) * 10);
	dev_dbg(dev, "Firmware library version 0x%02x%02x\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_LIB_VER_H),
	ft6236_debug_read_byte(ft6236, FT6236_REG_LIB_VER_L));
	dev_dbg(dev, "Firmware version 0x%02x\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_FIRMID));
	dev_dbg(dev, "Chip vendor ID 0x%02x\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_CIPHER));
	dev_dbg(dev, "CTPM vendor ID 0x%02x\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_FOCALTECH_ID));
	dev_dbg(dev, "Release code version 0x%02x\n",
	ft6236_debug_read_byte(ft6236, FT6236_REG_RELEASE_CODE_ID));
	}

	static void ft6236_reset(struct ft6236_data *ft6236)
	{
	if (!ft6236->reset_gpio)
	return;

	gpiod_set_value_cansleep(ft6236->reset_gpio, 1);
	usleep_range(5000, 20000);
	gpiod_set_value_cansleep(ft6236->reset_gpio, 0);
	msleep(300);
	}

	static int ft6236_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct device *dev = &client->dev;
	struct ft6236_data *ft6236;
	struct input_dev *input;
	u32 fuzz_x = 0, fuzz_y = 0;
	u8 val;
	int error;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
	return -ENXIO;

	if (!client->irq) {
	dev_err(dev, "irq is missing\n");
	return -EINVAL;
	}

	ft6236 = devm_kzalloc(dev, sizeof(*ft6236), GFP_KERNEL);
	if (!ft6236)
	return -ENOMEM;

	ft6236->client = client;
	ft6236->reset_gpio = devm_gpiod_get_optional(dev, "reset",
	GPIOD_OUT_LOW);
	if (IS_ERR(ft6236->reset_gpio)) {
	error = PTR_ERR(ft6236->reset_gpio);
	if (error != -EPROBE_DEFER)
	dev_err(dev, "error getting reset gpio: %d\n", error);
	return error;
	}

	ft6236_reset(ft6236);

	/* verify that the controller is present */
	error = ft6236_read(client, 0x00, 1, &val);
	if (error) {
	dev_err(dev, "failed to read from controller: %d\n", error);
	return error;
	}

	ft6236_debug_info(ft6236);

	input = devm_input_allocate_device(dev);
	if (!input)
	return -ENOMEM;

	ft6236->input = input;
	input->name = client->name;
	input->id.bustype = BUS_I2C;

	if (device_property_read_u32(dev, "touchscreen-size-x",
	&ft6236->max_x) \|\|
	device_property_read_u32(dev, "touchscreen-size-y",
	&ft6236->max_y)) {
	dev_err(dev, "touchscreen-size-x and/or -y missing\n");
	return -EINVAL;
	}

	device_property_read_u32(dev, "touchscreen-fuzz-x", &fuzz_x);
	device_property_read_u32(dev, "touchscreen-fuzz-y", &fuzz_y);
	ft6236->invert_x = device_property_read_bool(dev,
	"touchscreen-inverted-x");
	ft6236->invert_y = device_property_read_bool(dev,
	"touchscreen-inverted-y");
	ft6236->swap_xy = device_property_read_bool(dev,
	"touchscreen-swapped-x-y");

	if (ft6236->swap_xy) {
	input_set_abs_params(input, ABS_MT_POSITION_X, 0,
	ft6236->max_y, fuzz_y, 0);
	input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
	ft6236->max_x, fuzz_x, 0);
	} else {
	input_set_abs_params(input, ABS_MT_POSITION_X, 0,
	ft6236->max_x, fuzz_x, 0);
	input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
	ft6236->max_y, fuzz_y, 0);
	}

	error = input_mt_init_slots(input, FT6236_MAX_TOUCH_POINTS,
	INPUT_MT_DIRECT \| INPUT_MT_DROP_UNUSED);
	if (error)
	return error;

	error = devm_request_threaded_irq(dev, client->irq, NULL,
	ft6236_interrupt, IRQF_ONESHOT,
	client->name, ft6236);
	if (error) {
	dev_err(dev, "request irq %d failed: %d\n", client->irq, error);
	return error;
	}

	error = input_register_device(input);
	if (error) {
	dev_err(dev, "failed to register input device: %d\n", error);
	return error;
	}

	return 0;
	}

	#ifdef CONFIG_OF
	static const struct of_device_id ft6236_of_match[] = {
	{ .compatible = "focaltech,ft6236", },
	{ }
	};
	MODULE_DEVICE_TABLE(of, ft6236_of_match);
	#endif

	static const struct i2c_device_id ft6236_id[] = {
	{ "ft6236", },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, ft6236_id);

	static struct i2c_driver ft6236_driver = {
	.driver = {
	.name = "ft6236",
	.of_match_table = of_match_ptr(ft6236_of_match),
	},
	.probe = ft6236_probe,
	.id_table = ft6236_id,
	};
	module_i2c_driver(ft6236_driver);

	MODULE_AUTHOR("Sean Cross <xobs@kosagi.com>");
	MODULE_AUTHOR("Noralf Trønnes <noralf@tronnes.org>");
	MODULE_DESCRIPTION("FocalTech FT6236 TouchScreen driver");
	MODULE_LICENSE("GPL v2");