drivers/input/touchscreen/synaptics_tcm/synaptics_tcm_i2c.c - kernel/msm - Git at Google

 /*
  * Synaptics TCM touchscreen driver
  *
  * Copyright (C) 2017-2019 Synaptics Incorporated. All rights reserved.
  *
  * Copyright (C) 2017-2019 Scott Lin <scott.lin@tw.synaptics.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * 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.
  *
  * INFORMATION CONTAINED IN THIS DOCUMENT IS PROVIDED "AS-IS," AND SYNAPTICS
  * EXPRESSLY DISCLAIMS ALL EXPRESS AND IMPLIED WARRANTIES, INCLUDING ANY
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE,
  * AND ANY WARRANTIES OF NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHTS.
  * IN NO EVENT SHALL SYNAPTICS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES ARISING OUT OF OR IN CONNECTION
  * WITH THE USE OF THE INFORMATION CONTAINED IN THIS DOCUMENT, HOWEVER CAUSED
  * AND BASED ON ANY THEORY OF LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  * NEGLIGENCE OR OTHER TORTIOUS ACTION, AND EVEN IF SYNAPTICS WAS ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE. IF A TRIBUNAL OF COMPETENT JURISDICTION DOES
  * NOT PERMIT THE DISCLAIMER OF DIRECT DAMAGES OR ANY OTHER DAMAGES, SYNAPTICS'
  * TOTAL CUMULATIVE LIABILITY TO ANY PARTY SHALL NOT EXCEED ONE HUNDRED U.S.
  * DOLLARS.
  */

 #include <linux/i2c.h>
 #include <linux/of_gpio.h>
 #include "synaptics_tcm_core.h"
 #include "linux/moduleparam.h"

 #define XFER_ATTEMPTS 10

 static unsigned char *buf;

 static unsigned int buf_size;

 static struct syna_tcm_bus_io bus_io;

 static struct syna_tcm_hw_interface hw_if;

 static struct platform_device *syna_tcm_i2c_device;

 active_tp_setup(synaptics_tcm);

 #ifdef CONFIG_OF
 static int parse_dt(struct device *dev, struct syna_tcm_board_data *bdata)
 {
 	int retval;
 	u32 value;
 	struct property *prop;
 	struct device_node *np = dev->of_node;
 	const char *name;

 	prop = of_find_property(np, "synaptics,irq-gpio", NULL);
 	if (prop && prop->length) {
 		bdata->irq_gpio = of_get_named_gpio_flags(np,
 				"synaptics,irq-gpio", 0,
 				(enum of_gpio_flags *)&bdata->irq_flags);
 	} else {
 		bdata->irq_gpio = -1;
 	}

 	retval = of_property_read_u32(np, "synaptics,irq-on-state", &value);
 	if (retval < 0)
 		bdata->irq_on_state = 0;
 	else
 		bdata->irq_on_state = value;

 	retval = of_property_read_string(np, "synaptics,pwr-reg-name", &name);
 	if (retval < 0)
 		bdata->pwr_reg_name = NULL;
 	else
 		bdata->pwr_reg_name = name;

 	retval = of_property_read_string(np, "synaptics,bus-reg-name", &name);
 	if (retval < 0)
 		bdata->bus_reg_name = NULL;
 	else
 		bdata->bus_reg_name = name;

 	prop = of_find_property(np, "synaptics,power-gpio", NULL);
 	if (prop && prop->length) {
 		bdata->power_gpio = of_get_named_gpio_flags(np,
 				"synaptics,power-gpio", 0, NULL);
 	} else {
 		bdata->power_gpio = -1;
 	}

 	prop = of_find_property(np, "synaptics,power-on-state", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,power-on-state",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Failed to read synaptics,power-on-state\n");
 			return retval;
 		}
 		bdata->power_on_state = value;
 	} else {
 		bdata->power_on_state = 0;
 	}

 	prop = of_find_property(np, "synaptics,power-delay-ms", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,power-delay-ms",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Failed to read synaptics,power-delay-ms\n");
 			return retval;
 		}
 		bdata->power_delay_ms = value;
 	} else {
 		bdata->power_delay_ms = 0;
 	}

 	prop = of_find_property(np, "synaptics,reset-gpio", NULL);
 	if (prop && prop->length) {
 		bdata->reset_gpio = of_get_named_gpio_flags(np,
 				"synaptics,reset-gpio", 0, NULL);
 	} else {
 		bdata->reset_gpio = -1;
 	}

 	prop = of_find_property(np, "synaptics,reset-on-state", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,reset-on-state",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Failed to read synaptics,reset-on-state\n");
 			return retval;
 		}
 		bdata->reset_on_state = value;
 	} else {
 		bdata->reset_on_state = 0;
 	}

 	prop = of_find_property(np, "synaptics,reset-active-ms", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,reset-active-ms",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Failed to read synaptics,reset-active-ms\n");
 			return retval;
 		}
 		bdata->reset_active_ms = value;
 	} else {
 		bdata->reset_active_ms = 0;
 	}

 	prop = of_find_property(np, "synaptics,reset-delay-ms", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,reset-delay-ms",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Unable to read synaptics,reset-delay-ms\n");
 			return retval;
 		}
 		bdata->reset_delay_ms = value;
 	} else {
 		bdata->reset_delay_ms = 0;
 	}

 	prop = of_find_property(np, "synaptics,x-flip", NULL);
 	bdata->x_flip = prop > 0 ? true : false;

 	prop = of_find_property(np, "synaptics,y-flip", NULL);
 	bdata->y_flip = prop > 0 ? true : false;

 	prop = of_find_property(np, "synaptics,swap-axes", NULL);
 	bdata->swap_axes = prop > 0 ? true : false;

 	prop = of_find_property(np, "synaptics,ubl-i2c-addr", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,ubl-i2c-addr",
 				&value);
 		if (retval < 0) {
 			LOGE(dev, "Unable to read synaptics,ubl-i2c-addr\n");
 			return retval;
 		}
 		bdata->ubl_i2c_addr = value;
 	} else {
 		bdata->ubl_i2c_addr = 0;
 	}

 	return 0;
 }
 #endif

 static int syna_tcm_i2c_alloc_mem(struct syna_tcm_hcd *tcm_hcd,
 		unsigned int size)
 {
 	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

 	if (size > buf_size) {
 		if (buf_size)
 			kfree(buf);
 		buf = kmalloc(size, GFP_KERNEL);
 		if (!buf) {
 			LOGE(&i2c->dev,
 					"Failed to allocate memory for buf\n");
 			buf_size = 0;
 			return -ENOMEM;
 		}
 		buf_size = size;
 	}

 	return 0;
 }

 static int syna_tcm_i2c_rmi_read(struct syna_tcm_hcd *tcm_hcd,
 		unsigned short addr, unsigned char *data, unsigned int length)
 {
 	int retval;
 	unsigned char address;
 	unsigned int attempt;
 	struct i2c_msg msg[2];
 	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);
 	const struct syna_tcm_board_data *bdata = tcm_hcd->hw_if->bdata;

 	mutex_lock(&tcm_hcd->io_ctrl_mutex);

 	address = (unsigned char)addr;

 	msg[0].addr = bdata->ubl_i2c_addr;
 	msg[0].flags = 0;
 	msg[0].len = 1;
 	msg[0].buf = &address;

 	msg[1].addr = bdata->ubl_i2c_addr;
 	msg[1].flags = I2C_M_RD;
 	msg[1].len = length;
 	msg[1].buf = data;

 	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
 		if (i2c_transfer(i2c->adapter, msg, 2) == 2) {
 			retval = length;
 			goto exit;
 		}

 		LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

 		if (attempt + 1 == XFER_ATTEMPTS) {
 			LOGE(&i2c->dev, "Transfer failed\n");
 			retval = -EIO;
 			goto exit;
 		}

 		msleep(20);
 	}

 exit:
 	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

 	return retval;
 }

 static int syna_tcm_i2c_rmi_write(struct syna_tcm_hcd *tcm_hcd,
 		unsigned short addr, unsigned char *data, unsigned int length)
 {
 	int retval;
 	unsigned int attempt;
 	unsigned int byte_count;
 	struct i2c_msg msg;
 	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);
 	const struct syna_tcm_board_data *bdata = tcm_hcd->hw_if->bdata;

 	mutex_lock(&tcm_hcd->io_ctrl_mutex);

 	byte_count = length + 1;

 	retval = syna_tcm_i2c_alloc_mem(tcm_hcd, byte_count);
 	if (retval < 0) {
 		LOGE(&i2c->dev,
 				"Failed to allocate memory\n");
 		goto exit;
 	}

 	buf[0] = (unsigned char)addr;
 	retval = secure_memcpy(&buf[1],
 			buf_size - 1,
 			data,
 			length,
 			length);
 	if (retval < 0) {
 		LOGE(&i2c->dev,
 				"Failed to copy write data\n");
 		goto exit;
 	}

 	msg.addr = bdata->ubl_i2c_addr;
 	msg.flags = 0;
 	msg.len = byte_count;
 	msg.buf = buf;

 	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
 		if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
 			retval = length;
 			goto exit;
 		}

 		LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

 		if (attempt + 1 == XFER_ATTEMPTS) {
 			LOGE(&i2c->dev, "Transfer failed\n");
 			retval = -EIO;
 			goto exit;
 		}

 		msleep(20);
 	}

 exit:
 	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

 	return retval;
 }

 static int syna_tcm_i2c_read(struct syna_tcm_hcd *tcm_hcd, unsigned char *data,
 		unsigned int length)
 {
 	int retval;
 	unsigned int attempt;
 	struct i2c_msg msg;
 	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

 	mutex_lock(&tcm_hcd->io_ctrl_mutex);

 	msg.addr = i2c->addr;
 	msg.flags = I2C_M_RD;
 	msg.len = length;
 	msg.buf = data;

 	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
 		if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
 			retval = length;
 			goto exit;
 		}

 		LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

 		if (attempt + 1 == XFER_ATTEMPTS) {
 			LOGE(&i2c->dev, "Transfer failed\n");
 			retval = -EIO;
 			goto exit;
 		}

 		msleep(20);
 	}

 exit:
 	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

 	return retval;
 }

 static int syna_tcm_i2c_write(struct syna_tcm_hcd *tcm_hcd, unsigned char *data,
 		unsigned int length)
 {
 	int retval;
 	unsigned int attempt;
 	struct i2c_msg msg;
 	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

 	mutex_lock(&tcm_hcd->io_ctrl_mutex);

 	msg.addr = i2c->addr;
 	msg.flags = 0;
 	msg.len = length;
 	msg.buf = data;

 	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
 		if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
 			retval = length;
 			goto exit;
 		}

 		LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

 		if (attempt + 1 == XFER_ATTEMPTS) {
 			LOGE(&i2c->dev, "Transfer failed\n");
 			retval = -EIO;
 			goto exit;
 		}

 		msleep(20);
 	}

 exit:
 	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

 	return retval;
 }

 static int syna_tcm_i2c_probe(struct i2c_client *i2c,
 		const struct i2c_device_id *dev_id)
 {
 	int retval;
 	struct device_node *dt = i2c->dev.of_node;

 	if (synaptics_tcm_check_assigned_tp(dt, "compatible",
 				"qcom,i2c-touch-active") < 0)
 		return -ENODEV;

 	syna_tcm_i2c_device = platform_device_alloc(PLATFORM_DRIVER_NAME, 0);
 	if (!syna_tcm_i2c_device) {
 		LOGE(&i2c->dev,
 				"Failed to allocate platform device\n");
 		return -ENOMEM;
 	}

 #ifdef CONFIG_OF
 	hw_if.bdata = devm_kzalloc(&i2c->dev, sizeof(*hw_if.bdata), GFP_KERNEL);
 	if (!hw_if.bdata) {
 		LOGE(&i2c->dev,
 				"Failed to allocate memory for board data\n");
 		return -ENOMEM;
 	}
 	parse_dt(&i2c->dev, hw_if.bdata);
 #else
 	hw_if.bdata = i2c->dev.platform_data;
 #endif

 	bus_io.type = BUS_I2C;
 	bus_io.read = syna_tcm_i2c_read;
 	bus_io.write = syna_tcm_i2c_write;
 	bus_io.rmi_read = syna_tcm_i2c_rmi_read;
 	bus_io.rmi_write = syna_tcm_i2c_rmi_write;

 	hw_if.bus_io = &bus_io;

 	syna_tcm_i2c_device->dev.parent = &i2c->dev;
 	syna_tcm_i2c_device->dev.platform_data = &hw_if;

 	retval = platform_device_add(syna_tcm_i2c_device);
 	if (retval < 0) {
 		LOGE(&i2c->dev,
 				"Failed to add platform device\n");
 		return retval;
 	}

 	return 0;
 }

 static int syna_tcm_i2c_remove(struct i2c_client *i2c)
 {
 	syna_tcm_i2c_device->dev.platform_data = NULL;

 	platform_device_unregister(syna_tcm_i2c_device);

 	return 0;
 }

 static const struct i2c_device_id syna_tcm_id_table[] = {
 	{I2C_MODULE_NAME, 0},
 	{},
 };
 MODULE_DEVICE_TABLE(i2c, syna_tcm_id_table);

 #ifdef CONFIG_OF
 static const struct of_device_id syna_tcm_of_match_table[] = {
 	{
 		.compatible = "synaptics,tcm-i2c",
 	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, syna_tcm_of_match_table);
 #else
 #define syna_tcm_of_match_table NULL
 #endif

 static struct i2c_driver syna_tcm_i2c_driver = {
 	.driver = {
 		.name = I2C_MODULE_NAME,
 		.owner = THIS_MODULE,
 		.of_match_table = syna_tcm_of_match_table,
 	},
 	.probe = syna_tcm_i2c_probe,
 	.remove = syna_tcm_i2c_remove,
 	.id_table = syna_tcm_id_table,
 };

 int syna_tcm_bus_init(void)
 {
 	return i2c_add_driver(&syna_tcm_i2c_driver);
 }
 EXPORT_SYMBOL(syna_tcm_bus_init);

 void syna_tcm_bus_exit(void)
 {
 	kfree(buf);

 	i2c_del_driver(&syna_tcm_i2c_driver);
 }
 EXPORT_SYMBOL(syna_tcm_bus_exit);

 MODULE_AUTHOR("Synaptics, Inc.");
 MODULE_DESCRIPTION("Synaptics TCM I2C Bus Module");
 MODULE_LICENSE("GPL v2");
	/*
	* Synaptics TCM touchscreen driver
	*
	* Copyright (C) 2017-2019 Synaptics Incorporated. All rights reserved.
	*
	* Copyright (C) 2017-2019 Scott Lin <scott.lin@tw.synaptics.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* 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.
	*
	* INFORMATION CONTAINED IN THIS DOCUMENT IS PROVIDED "AS-IS," AND SYNAPTICS
	* EXPRESSLY DISCLAIMS ALL EXPRESS AND IMPLIED WARRANTIES, INCLUDING ANY
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE,
	* AND ANY WARRANTIES OF NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHTS.
	* IN NO EVENT SHALL SYNAPTICS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES ARISING OUT OF OR IN CONNECTION
	* WITH THE USE OF THE INFORMATION CONTAINED IN THIS DOCUMENT, HOWEVER CAUSED
	* AND BASED ON ANY THEORY OF LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	* NEGLIGENCE OR OTHER TORTIOUS ACTION, AND EVEN IF SYNAPTICS WAS ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE. IF A TRIBUNAL OF COMPETENT JURISDICTION DOES
	* NOT PERMIT THE DISCLAIMER OF DIRECT DAMAGES OR ANY OTHER DAMAGES, SYNAPTICS'
	* TOTAL CUMULATIVE LIABILITY TO ANY PARTY SHALL NOT EXCEED ONE HUNDRED U.S.
	* DOLLARS.
	*/

	#include <linux/i2c.h>
	#include <linux/of_gpio.h>
	#include "synaptics_tcm_core.h"
	#include "linux/moduleparam.h"

	#define XFER_ATTEMPTS 10

	static unsigned char *buf;

	static unsigned int buf_size;

	static struct syna_tcm_bus_io bus_io;

	static struct syna_tcm_hw_interface hw_if;

	static struct platform_device *syna_tcm_i2c_device;

	active_tp_setup(synaptics_tcm);

	#ifdef CONFIG_OF
	static int parse_dt(struct device dev, struct syna_tcm_board_data bdata)
	{
	int retval;
	u32 value;
	struct property *prop;
	struct device_node *np = dev->of_node;
	const char *name;

	prop = of_find_property(np, "synaptics,irq-gpio", NULL);
	if (prop && prop->length) {
	bdata->irq_gpio = of_get_named_gpio_flags(np,
	"synaptics,irq-gpio", 0,
	(enum of_gpio_flags *)&bdata->irq_flags);
	} else {
	bdata->irq_gpio = -1;
	}

	retval = of_property_read_u32(np, "synaptics,irq-on-state", &value);
	if (retval < 0)
	bdata->irq_on_state = 0;
	else
	bdata->irq_on_state = value;

	retval = of_property_read_string(np, "synaptics,pwr-reg-name", &name);
	if (retval < 0)
	bdata->pwr_reg_name = NULL;
	else
	bdata->pwr_reg_name = name;

	retval = of_property_read_string(np, "synaptics,bus-reg-name", &name);
	if (retval < 0)
	bdata->bus_reg_name = NULL;
	else
	bdata->bus_reg_name = name;

	prop = of_find_property(np, "synaptics,power-gpio", NULL);
	if (prop && prop->length) {
	bdata->power_gpio = of_get_named_gpio_flags(np,
	"synaptics,power-gpio", 0, NULL);
	} else {
	bdata->power_gpio = -1;
	}

	prop = of_find_property(np, "synaptics,power-on-state", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,power-on-state",
	&value);
	if (retval < 0) {
	LOGE(dev, "Failed to read synaptics,power-on-state\n");
	return retval;
	}
	bdata->power_on_state = value;
	} else {
	bdata->power_on_state = 0;
	}

	prop = of_find_property(np, "synaptics,power-delay-ms", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,power-delay-ms",
	&value);
	if (retval < 0) {
	LOGE(dev, "Failed to read synaptics,power-delay-ms\n");
	return retval;
	}
	bdata->power_delay_ms = value;
	} else {
	bdata->power_delay_ms = 0;
	}

	prop = of_find_property(np, "synaptics,reset-gpio", NULL);
	if (prop && prop->length) {
	bdata->reset_gpio = of_get_named_gpio_flags(np,
	"synaptics,reset-gpio", 0, NULL);
	} else {
	bdata->reset_gpio = -1;
	}

	prop = of_find_property(np, "synaptics,reset-on-state", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,reset-on-state",
	&value);
	if (retval < 0) {
	LOGE(dev, "Failed to read synaptics,reset-on-state\n");
	return retval;
	}
	bdata->reset_on_state = value;
	} else {
	bdata->reset_on_state = 0;
	}

	prop = of_find_property(np, "synaptics,reset-active-ms", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,reset-active-ms",
	&value);
	if (retval < 0) {
	LOGE(dev, "Failed to read synaptics,reset-active-ms\n");
	return retval;
	}
	bdata->reset_active_ms = value;
	} else {
	bdata->reset_active_ms = 0;
	}

	prop = of_find_property(np, "synaptics,reset-delay-ms", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,reset-delay-ms",
	&value);
	if (retval < 0) {
	LOGE(dev, "Unable to read synaptics,reset-delay-ms\n");
	return retval;
	}
	bdata->reset_delay_ms = value;
	} else {
	bdata->reset_delay_ms = 0;
	}

	prop = of_find_property(np, "synaptics,x-flip", NULL);
	bdata->x_flip = prop > 0 ? true : false;

	prop = of_find_property(np, "synaptics,y-flip", NULL);
	bdata->y_flip = prop > 0 ? true : false;

	prop = of_find_property(np, "synaptics,swap-axes", NULL);
	bdata->swap_axes = prop > 0 ? true : false;

	prop = of_find_property(np, "synaptics,ubl-i2c-addr", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,ubl-i2c-addr",
	&value);
	if (retval < 0) {
	LOGE(dev, "Unable to read synaptics,ubl-i2c-addr\n");
	return retval;
	}
	bdata->ubl_i2c_addr = value;
	} else {
	bdata->ubl_i2c_addr = 0;
	}

	return 0;
	}
	#endif

	static int syna_tcm_i2c_alloc_mem(struct syna_tcm_hcd *tcm_hcd,
	unsigned int size)
	{
	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

	if (size > buf_size) {
	if (buf_size)
	kfree(buf);
	buf = kmalloc(size, GFP_KERNEL);
	if (!buf) {
	LOGE(&i2c->dev,
	"Failed to allocate memory for buf\n");
	buf_size = 0;
	return -ENOMEM;
	}
	buf_size = size;
	}

	return 0;
	}

	static int syna_tcm_i2c_rmi_read(struct syna_tcm_hcd *tcm_hcd,
	unsigned short addr, unsigned char *data, unsigned int length)
	{
	int retval;
	unsigned char address;
	unsigned int attempt;
	struct i2c_msg msg[2];
	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);
	const struct syna_tcm_board_data *bdata = tcm_hcd->hw_if->bdata;

	mutex_lock(&tcm_hcd->io_ctrl_mutex);

	address = (unsigned char)addr;

	msg[0].addr = bdata->ubl_i2c_addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = &address;

	msg[1].addr = bdata->ubl_i2c_addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = length;
	msg[1].buf = data;

	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
	if (i2c_transfer(i2c->adapter, msg, 2) == 2) {
	retval = length;
	goto exit;
	}

	LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

	if (attempt + 1 == XFER_ATTEMPTS) {
	LOGE(&i2c->dev, "Transfer failed\n");
	retval = -EIO;
	goto exit;
	}

	msleep(20);
	}

	exit:
	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

	return retval;
	}

	static int syna_tcm_i2c_rmi_write(struct syna_tcm_hcd *tcm_hcd,
	unsigned short addr, unsigned char *data, unsigned int length)
	{
	int retval;
	unsigned int attempt;
	unsigned int byte_count;
	struct i2c_msg msg;
	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);
	const struct syna_tcm_board_data *bdata = tcm_hcd->hw_if->bdata;

	mutex_lock(&tcm_hcd->io_ctrl_mutex);

	byte_count = length + 1;

	retval = syna_tcm_i2c_alloc_mem(tcm_hcd, byte_count);
	if (retval < 0) {
	LOGE(&i2c->dev,
	"Failed to allocate memory\n");
	goto exit;
	}

	buf[0] = (unsigned char)addr;
	retval = secure_memcpy(&buf[1],
	buf_size - 1,
	data,
	length,
	length);
	if (retval < 0) {
	LOGE(&i2c->dev,
	"Failed to copy write data\n");
	goto exit;
	}

	msg.addr = bdata->ubl_i2c_addr;
	msg.flags = 0;
	msg.len = byte_count;
	msg.buf = buf;

	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
	if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
	retval = length;
	goto exit;
	}

	LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

	if (attempt + 1 == XFER_ATTEMPTS) {
	LOGE(&i2c->dev, "Transfer failed\n");
	retval = -EIO;
	goto exit;
	}

	msleep(20);
	}

	exit:
	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

	return retval;
	}

	static int syna_tcm_i2c_read(struct syna_tcm_hcd tcm_hcd, unsigned char data,
	unsigned int length)
	{
	int retval;
	unsigned int attempt;
	struct i2c_msg msg;
	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

	mutex_lock(&tcm_hcd->io_ctrl_mutex);

	msg.addr = i2c->addr;
	msg.flags = I2C_M_RD;
	msg.len = length;
	msg.buf = data;

	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
	if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
	retval = length;
	goto exit;
	}

	LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

	if (attempt + 1 == XFER_ATTEMPTS) {
	LOGE(&i2c->dev, "Transfer failed\n");
	retval = -EIO;
	goto exit;
	}

	msleep(20);
	}

	exit:
	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

	return retval;
	}

	static int syna_tcm_i2c_write(struct syna_tcm_hcd tcm_hcd, unsigned char data,
	unsigned int length)
	{
	int retval;
	unsigned int attempt;
	struct i2c_msg msg;
	struct i2c_client *i2c = to_i2c_client(tcm_hcd->pdev->dev.parent);

	mutex_lock(&tcm_hcd->io_ctrl_mutex);

	msg.addr = i2c->addr;
	msg.flags = 0;
	msg.len = length;
	msg.buf = data;

	for (attempt = 0; attempt < XFER_ATTEMPTS; attempt++) {
	if (i2c_transfer(i2c->adapter, &msg, 1) == 1) {
	retval = length;
	goto exit;
	}

	LOGD(&i2c->dev, "Transfer attempt %d times\n", attempt + 1);

	if (attempt + 1 == XFER_ATTEMPTS) {
	LOGE(&i2c->dev, "Transfer failed\n");
	retval = -EIO;
	goto exit;
	}

	msleep(20);
	}

	exit:
	mutex_unlock(&tcm_hcd->io_ctrl_mutex);

	return retval;
	}

	static int syna_tcm_i2c_probe(struct i2c_client *i2c,
	const struct i2c_device_id *dev_id)
	{
	int retval;
	struct device_node *dt = i2c->dev.of_node;

	if (synaptics_tcm_check_assigned_tp(dt, "compatible",
	"qcom,i2c-touch-active") < 0)
	return -ENODEV;

	syna_tcm_i2c_device = platform_device_alloc(PLATFORM_DRIVER_NAME, 0);
	if (!syna_tcm_i2c_device) {
	LOGE(&i2c->dev,
	"Failed to allocate platform device\n");
	return -ENOMEM;
	}

	#ifdef CONFIG_OF
	hw_if.bdata = devm_kzalloc(&i2c->dev, sizeof(*hw_if.bdata), GFP_KERNEL);
	if (!hw_if.bdata) {
	LOGE(&i2c->dev,
	"Failed to allocate memory for board data\n");
	return -ENOMEM;
	}
	parse_dt(&i2c->dev, hw_if.bdata);
	#else
	hw_if.bdata = i2c->dev.platform_data;
	#endif

	bus_io.type = BUS_I2C;
	bus_io.read = syna_tcm_i2c_read;
	bus_io.write = syna_tcm_i2c_write;
	bus_io.rmi_read = syna_tcm_i2c_rmi_read;
	bus_io.rmi_write = syna_tcm_i2c_rmi_write;

	hw_if.bus_io = &bus_io;

	syna_tcm_i2c_device->dev.parent = &i2c->dev;
	syna_tcm_i2c_device->dev.platform_data = &hw_if;

	retval = platform_device_add(syna_tcm_i2c_device);
	if (retval < 0) {
	LOGE(&i2c->dev,
	"Failed to add platform device\n");
	return retval;
	}

	return 0;
	}

	static int syna_tcm_i2c_remove(struct i2c_client *i2c)
	{
	syna_tcm_i2c_device->dev.platform_data = NULL;

	platform_device_unregister(syna_tcm_i2c_device);

	return 0;
	}

	static const struct i2c_device_id syna_tcm_id_table[] = {
	{I2C_MODULE_NAME, 0},
	{},
	};
	MODULE_DEVICE_TABLE(i2c, syna_tcm_id_table);

	#ifdef CONFIG_OF
	static const struct of_device_id syna_tcm_of_match_table[] = {
	{
	.compatible = "synaptics,tcm-i2c",
	},
	{},
	};
	MODULE_DEVICE_TABLE(of, syna_tcm_of_match_table);
	#else
	#define syna_tcm_of_match_table NULL
	#endif

	static struct i2c_driver syna_tcm_i2c_driver = {
	.driver = {
	.name = I2C_MODULE_NAME,
	.owner = THIS_MODULE,
	.of_match_table = syna_tcm_of_match_table,
	},
	.probe = syna_tcm_i2c_probe,
	.remove = syna_tcm_i2c_remove,
	.id_table = syna_tcm_id_table,
	};

	int syna_tcm_bus_init(void)
	{
	return i2c_add_driver(&syna_tcm_i2c_driver);
	}
	EXPORT_SYMBOL(syna_tcm_bus_init);

	void syna_tcm_bus_exit(void)
	{
	kfree(buf);

	i2c_del_driver(&syna_tcm_i2c_driver);
	}
	EXPORT_SYMBOL(syna_tcm_bus_exit);

	MODULE_AUTHOR("Synaptics, Inc.");
	MODULE_DESCRIPTION("Synaptics TCM I2C Bus Module");
	MODULE_LICENSE("GPL v2");