drivers/input/touchscreen/synaptics_dsx_2.6/synaptics_dsx_i2c.c - kernel/msm-4.9 - Gitiles

 /*
  * Synaptics DSX touchscreen driver
  *
  * Copyright (C) 2012-2015 Synaptics Incorporated. All rights reserved.
  *
  * Copyright (C) 2012 Alexandra Chin <alexandra.chin@tw.synaptics.com>
  * Copyright (C) 2012 Scott Lin <scott.lin@tw.synaptics.com>
  * Copyright (C) 2018 The Linux Foundation. All rights reserved.
  *
  * 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/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/delay.h>
 #include <linux/input.h>
 #include <linux/types.h>
 #include <linux/of_gpio.h>
 #include <linux/platform_device.h>
 #include <linux/input/synaptics_dsx_v2_6.h>
 #include "synaptics_dsx_core.h"

 #define SYN_I2C_RETRY_TIMES 10

 /*
 #define I2C_BURST_LIMIT 255
 */

 #define XFER_MSGS_LIMIT 8

 static unsigned char *wr_buf;

 static struct synaptics_dsx_hw_interface hw_if;

 static struct platform_device *synaptics_dsx_i2c_device;

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

 	bdata->irq_gpio = of_get_named_gpio_flags(np,
 			"synaptics,irq-gpio", 0,
 			(enum of_gpio_flags *)&bdata->irq_flags);

 	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;

 	bdata->resume_in_workqueue = of_property_read_bool(np,
 			"synaptics,resume-in-workqueue");

 	bdata->wakeup_gesture_en = of_property_read_bool(np,
 			"synaptics,wakeup-gestures-en");

 	bdata->dont_disable_regs = of_property_read_bool(np,
 			"synaptics,do-not-disable-regulators");

 	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);
 		retval = of_property_read_u32(np, "synaptics,power-on-state",
 				&value);
 		if (retval < 0) {
 			dev_err(dev, "%s: Unable to read synaptics,power-on-state property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->power_on_state = value;
 		}
 	} else {
 		bdata->power_gpio = -1;
 	}

 	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) {
 			dev_err(dev, "%s: Unable to read synaptics,power-delay-ms property\n",
 					__func__);
 			return retval;
 		} else {
 			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);
 		retval = of_property_read_u32(np, "synaptics,reset-on-state",
 				&value);
 		if (retval < 0) {
 			dev_err(dev, "%s: Unable to read synaptics,reset-on-state property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->reset_on_state = value;
 		}
 		retval = of_property_read_u32(np, "synaptics,reset-active-ms",
 				&value);
 		if (retval < 0) {
 			dev_err(dev, "%s: Unable to read synaptics,reset-active-ms property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->reset_active_ms = value;
 		}
 	} else {
 		bdata->reset_gpio = -1;
 	}

 	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) {
 			dev_err(dev, "%s: Unable to read synaptics,reset-delay-ms property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->reset_delay_ms = value;
 		}
 	} else {
 		bdata->reset_delay_ms = 0;
 	}

 	prop = of_find_property(np, "synaptics,max-y-for-2d", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,max-y-for-2d",
 				&value);
 		if (retval < 0) {
 			dev_err(dev, "%s: Unable to read synaptics,max-y-for-2d property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->max_y_for_2d = value;
 		}
 	} else {
 		bdata->max_y_for_2d = -1;
 	}

 	retval = of_property_read_u32(np, "synaptics,bus-lpm-cur-uA",
 			&value);
 	bdata->bus_lpm_cur_uA = retval < 0 ? 0 : value;

 	bdata->swap_axes = of_property_read_bool(np, "synaptics,swap-axes");
 	bdata->x_flip = of_property_read_bool(np, "synaptics,x-flip");
 	bdata->y_flip = of_property_read_bool(np, "synaptics,y-flip");

 	prop = of_find_property(np, "synaptics,ub-i2c-addr", NULL);
 	if (prop && prop->length) {
 		retval = of_property_read_u32(np, "synaptics,ub-i2c-addr",
 				&value);
 		if (retval < 0) {
 			dev_err(dev, "%s: Unable to read synaptics,ub-i2c-addr property\n",
 					__func__);
 			return retval;
 		} else {
 			bdata->ub_i2c_addr = (unsigned short)value;
 		}
 	} else {
 		bdata->ub_i2c_addr = -1;
 	}

 	prop = of_find_property(np, "synaptics,cap-button-codes", NULL);
 	if (prop && prop->length) {
 		bdata->cap_button_map->map = devm_kzalloc(dev,
 				prop->length,
 				GFP_KERNEL);
 		if (!bdata->cap_button_map->map)
 			return -ENOMEM;
 		bdata->cap_button_map->nbuttons = prop->length / sizeof(u32);
 		retval = of_property_read_u32_array(np,
 				"synaptics,cap-button-codes",
 				bdata->cap_button_map->map,
 				bdata->cap_button_map->nbuttons);
 		if (retval < 0) {
 			bdata->cap_button_map->nbuttons = 0;
 			bdata->cap_button_map->map = NULL;
 		}
 	} else {
 		bdata->cap_button_map->nbuttons = 0;
 		bdata->cap_button_map->map = NULL;
 	}

 	prop = of_find_property(np, "synaptics,vir-button-codes", NULL);
 	if (prop && prop->length) {
 		bdata->vir_button_map->map = devm_kzalloc(dev,
 				prop->length,
 				GFP_KERNEL);
 		if (!bdata->vir_button_map->map)
 			return -ENOMEM;
 		bdata->vir_button_map->nbuttons = prop->length / sizeof(u32);
 		bdata->vir_button_map->nbuttons /= 5;
 		retval = of_property_read_u32_array(np,
 				"synaptics,vir-button-codes",
 				bdata->vir_button_map->map,
 				bdata->vir_button_map->nbuttons * 5);
 		if (retval < 0) {
 			bdata->vir_button_map->nbuttons = 0;
 			bdata->vir_button_map->map = NULL;
 		}
 	} else {
 		bdata->vir_button_map->nbuttons = 0;
 		bdata->vir_button_map->map = NULL;
 	}

 	return 0;
 }
 #endif

 static int synaptics_rmi4_i2c_alloc_buf(struct synaptics_rmi4_data *rmi4_data,
 		unsigned int count)
 {
 	static unsigned int buf_size;

 	if (count > buf_size) {
 		if (buf_size)
 			kfree(wr_buf);
 		wr_buf = kzalloc(count, GFP_KERNEL);
 		if (!wr_buf) {
 			dev_err(rmi4_data->pdev->dev.parent,
 					"%s: Failed to alloc mem for buffer\n",
 					__func__);
 			buf_size = 0;
 			return -ENOMEM;
 		}
 		buf_size = count;
 	}

 	return 0;
 }

 static void synaptics_rmi4_i2c_check_addr(struct synaptics_rmi4_data *rmi4_data,
 		struct i2c_client *i2c)
 {
 	if (hw_if.board_data->ub_i2c_addr == -1)
 		return;

 	if (hw_if.board_data->i2c_addr == i2c->addr)
 		hw_if.board_data->i2c_addr = hw_if.board_data->ub_i2c_addr;
 	else
 		hw_if.board_data->i2c_addr = i2c->addr;

 	return;
 }

 static int synaptics_rmi4_i2c_set_page(struct synaptics_rmi4_data *rmi4_data,
 		unsigned short addr)
 {
 	int retval = 0;
 	unsigned char retry;
 	unsigned char buf[PAGE_SELECT_LEN];
 	unsigned char page;
 	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
 	struct i2c_msg msg[1];

 	msg[0].addr = hw_if.board_data->i2c_addr;
 	msg[0].flags = 0;
 	msg[0].len = PAGE_SELECT_LEN;
 	msg[0].buf = buf;

 	page = ((addr >> 8) & MASK_8BIT);
 	buf[0] = MASK_8BIT;
 	buf[1] = page;

 	if (page != rmi4_data->current_page) {
 		for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
 			if (i2c_transfer(i2c->adapter, &msg[0], 1) == 1) {
 				rmi4_data->current_page = page;
 				retval = PAGE_SELECT_LEN;
 				break;
 			}
 			dev_err(rmi4_data->pdev->dev.parent,
 					"%s: I2C retry %d\n",
 					__func__, retry + 1);
 			msleep(20);

 			if (retry == SYN_I2C_RETRY_TIMES / 2) {
 				synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
 				msg[0].addr = hw_if.board_data->i2c_addr;
 			}
 		}
 	} else {
 		retval = PAGE_SELECT_LEN;
 	}

 	return retval;
 }

 static int synaptics_rmi4_i2c_read(struct synaptics_rmi4_data *rmi4_data,
 		unsigned short addr, unsigned char *data, unsigned short length)
 {
 	int retval;
 	unsigned char retry;
 	unsigned char buf;
 #ifdef I2C_BURST_LIMIT
 	unsigned char ii;
 	unsigned char rd_msgs = ((length - 1) / I2C_BURST_LIMIT) + 1;
 #else
 	unsigned char rd_msgs = 1;
 #endif
 	unsigned char index = 0;
 	unsigned char xfer_msgs;
 	unsigned char remaining_msgs;
 	unsigned short i2c_addr;
 	unsigned short data_offset = 0;
 	unsigned short remaining_length = length;
 	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
 	struct i2c_adapter *adap = i2c->adapter;
 	struct i2c_msg msg[XFER_MSGS_LIMIT + 1];

 	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);

 	retval = synaptics_rmi4_i2c_set_page(rmi4_data, addr);
 	if (retval != PAGE_SELECT_LEN) {
 		retval = -EIO;
 		goto exit;
 	}

 	msg[0].addr = hw_if.board_data->i2c_addr;
 	msg[0].flags = 0;
 	msg[0].len = 1;
 	msg[0].buf = &buf;

 #ifdef I2C_BURST_LIMIT
 	for (ii = 0; ii < (rd_msgs - 1); ii++) {
 		msg[ii + 1].addr = hw_if.board_data->i2c_addr;
 		msg[ii + 1].flags = I2C_M_RD;
 		msg[ii + 1].len = I2C_BURST_LIMIT;
 		msg[ii + 1].buf = &data[data_offset];
 		data_offset += I2C_BURST_LIMIT;
 		remaining_length -= I2C_BURST_LIMIT;
 	}
 #endif

 	msg[rd_msgs].addr = hw_if.board_data->i2c_addr;
 	msg[rd_msgs].flags = I2C_M_RD;
 	msg[rd_msgs].len = remaining_length;
 	msg[rd_msgs].buf = &data[data_offset];

 	buf = addr & MASK_8BIT;

 	remaining_msgs = rd_msgs + 1;

 	while (remaining_msgs) {
 		if (remaining_msgs > XFER_MSGS_LIMIT)
 			xfer_msgs = XFER_MSGS_LIMIT;
 		else
 			xfer_msgs = remaining_msgs;
 		for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
 			retval = i2c_transfer(adap, &msg[index], xfer_msgs);
 			if (retval == xfer_msgs)
 				break;

 			dev_err(rmi4_data->pdev->dev.parent,
 					"%s: I2C retry %d\n",
 					__func__, retry + 1);
 			msleep(20);

 			if (retry == SYN_I2C_RETRY_TIMES / 2) {
 				synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
 				i2c_addr = hw_if.board_data->i2c_addr;
 				msg[0].addr = i2c_addr;
 #ifdef I2C_BURST_LIMIT
 				for (ii = 0; ii < (rd_msgs - 1); ii++)
 					msg[ii + 1].addr = i2c_addr;
 #endif
 				msg[rd_msgs].addr = i2c_addr;
 			}
 		}

 		if (retry == SYN_I2C_RETRY_TIMES) {
 			dev_err(rmi4_data->pdev->dev.parent,
 					"%s: I2C read over retry limit\n",
 					__func__);
 			retval = -EIO;
 			goto exit;
 		}

 		remaining_msgs -= xfer_msgs;
 		index += xfer_msgs;
 	}

 	retval = length;

 exit:
 	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

 	return retval;
 }

 static int synaptics_rmi4_i2c_write(struct synaptics_rmi4_data *rmi4_data,
 		unsigned short addr, unsigned char *data, unsigned short length)
 {
 	int retval;
 	unsigned char retry;
 	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
 	struct i2c_msg msg[1];

 	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);

 	retval = synaptics_rmi4_i2c_alloc_buf(rmi4_data, length + 1);
 	if (retval < 0)
 		goto exit;

 	retval = synaptics_rmi4_i2c_set_page(rmi4_data, addr);
 	if (retval != PAGE_SELECT_LEN) {
 		retval = -EIO;
 		goto exit;
 	}

 	msg[0].addr = hw_if.board_data->i2c_addr;
 	msg[0].flags = 0;
 	msg[0].len = length + 1;
 	msg[0].buf = wr_buf;

 	wr_buf[0] = addr & MASK_8BIT;
 	retval = secure_memcpy(&wr_buf[1], length, &data[0], length, length);
 	if (retval < 0) {
 		dev_err(rmi4_data->pdev->dev.parent,
 				"%s: Failed to copy data\n",
 				__func__);
 		goto exit;
 	}

 	for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
 		if (i2c_transfer(i2c->adapter, &msg[0], 1) == 1) {
 			retval = length;
 			break;
 		}
 		dev_err(rmi4_data->pdev->dev.parent,
 				"%s: I2C retry %d\n",
 				__func__, retry + 1);
 		msleep(20);

 		if (retry == SYN_I2C_RETRY_TIMES / 2) {
 			synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
 			msg[0].addr = hw_if.board_data->i2c_addr;
 		}
 	}

 	if (retry == SYN_I2C_RETRY_TIMES) {
 		dev_err(rmi4_data->pdev->dev.parent,
 				"%s: I2C write over retry limit\n",
 				__func__);
 		retval = -EIO;
 	}

 exit:
 	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

 	return retval;
 }

 #if defined(CONFIG_SECURE_TOUCH_SYNAPTICS_DSX_V26)
 static int synaptics_rmi4_clk_prepare_enable(
 		struct synaptics_rmi4_data *rmi4_data)
 {
 	int ret;

 	ret = clk_prepare_enable(rmi4_data->iface_clk);
 	if (ret) {
 		dev_err(rmi4_data->pdev->dev.parent,
 			"error on clk_prepare_enable(iface_clk):%d\n", ret);
 		return ret;
 	}

 	ret = clk_prepare_enable(rmi4_data->core_clk);
 	if (ret) {
 		clk_disable_unprepare(rmi4_data->iface_clk);
 		dev_err(rmi4_data->pdev->dev.parent,
 			"error clk_prepare_enable(core_clk):%d\n", ret);
 	}
 	return ret;
 }

 static void synaptics_rmi4_clk_disable_unprepare(
 		struct synaptics_rmi4_data *rmi4_data)
 {
 	clk_disable_unprepare(rmi4_data->core_clk);
 	clk_disable_unprepare(rmi4_data->iface_clk);
 }

 static int synaptics_rmi4_i2c_get(struct synaptics_rmi4_data *rmi4_data)
 {
 	int retval;
 	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);

 	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);
 	retval = pm_runtime_get_sync(i2c->adapter->dev.parent);
 	if (retval >= 0 && rmi4_data->core_clk != NULL &&
 				rmi4_data->iface_clk != NULL) {
 		retval = synaptics_rmi4_clk_prepare_enable(rmi4_data);
 		if (retval)
 			pm_runtime_put_sync(i2c->adapter->dev.parent);
 	}
 	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

 	return retval;
 }

 static void synaptics_rmi4_i2c_put(struct synaptics_rmi4_data *rmi4_data)
 {
 	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);

 	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);
 	if (rmi4_data->core_clk != NULL && rmi4_data->iface_clk != NULL)
 		synaptics_rmi4_clk_disable_unprepare(rmi4_data);
 	pm_runtime_put_sync(i2c->adapter->dev.parent);
 	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);
 }
 #endif

 static struct synaptics_dsx_bus_access bus_access = {
 	.type = BUS_I2C,
 	.read = synaptics_rmi4_i2c_read,
 	.write = synaptics_rmi4_i2c_write,
 #if defined(CONFIG_SECURE_TOUCH_SYNAPTICS_DSX_V26)
 	.get = synaptics_rmi4_i2c_get,
 	.put = synaptics_rmi4_i2c_put,
 #endif
 };

 static void synaptics_rmi4_i2c_dev_release(struct device *dev)
 {
 	kfree(synaptics_dsx_i2c_device);

 	return;
 }

 static int synaptics_rmi4_i2c_probe(struct i2c_client *client,
 		const struct i2c_device_id *dev_id)
 {
 	int retval;

 	if (!i2c_check_functionality(client->adapter,
 			I2C_FUNC_SMBUS_BYTE_DATA)) {
 		dev_err(&client->dev,
 				"%s: SMBus byte data commands not supported by host\n",
 				__func__);
 		return -EIO;
 	}

 	synaptics_dsx_i2c_device = kzalloc(
 			sizeof(struct platform_device),
 			GFP_KERNEL);
 	if (!synaptics_dsx_i2c_device) {
 		dev_err(&client->dev,
 				"%s: Failed to allocate memory for synaptics_dsx_i2c_device\n",
 				__func__);
 		return -ENOMEM;
 	}

 #ifdef CONFIG_OF
 	if (client->dev.of_node) {
 		hw_if.board_data = devm_kzalloc(&client->dev,
 				sizeof(struct synaptics_dsx_board_data),
 				GFP_KERNEL);
 		if (!hw_if.board_data) {
 			dev_err(&client->dev,
 					"%s: Failed to allocate memory for board data\n",
 					__func__);
 			return -ENOMEM;
 		}
 		hw_if.board_data->cap_button_map = devm_kzalloc(&client->dev,
 				sizeof(struct synaptics_dsx_button_map),
 				GFP_KERNEL);
 		if (!hw_if.board_data->cap_button_map) {
 			dev_err(&client->dev,
 					"%s: Failed to allocate memory for 0D button map\n",
 					__func__);
 			return -ENOMEM;
 		}
 		hw_if.board_data->vir_button_map = devm_kzalloc(&client->dev,
 				sizeof(struct synaptics_dsx_button_map),
 				GFP_KERNEL);
 		if (!hw_if.board_data->vir_button_map) {
 			dev_err(&client->dev,
 					"%s: Failed to allocate memory for virtual button map\n",
 					__func__);
 			return -ENOMEM;
 		}
 		parse_dt(&client->dev, hw_if.board_data);
 	}
 #else
 	hw_if.board_data = client->dev.platform_data;
 #endif

 	hw_if.bus_access = &bus_access;
 	hw_if.board_data->i2c_addr = client->addr;

 	synaptics_dsx_i2c_device->name = PLATFORM_DRIVER_NAME;
 	synaptics_dsx_i2c_device->id = 0;
 	synaptics_dsx_i2c_device->num_resources = 0;
 	synaptics_dsx_i2c_device->dev.parent = &client->dev;
 	synaptics_dsx_i2c_device->dev.platform_data = &hw_if;
 	synaptics_dsx_i2c_device->dev.release = synaptics_rmi4_i2c_dev_release;

 	retval = platform_device_register(synaptics_dsx_i2c_device);
 	if (retval) {
 		dev_err(&client->dev,
 				"%s: Failed to register platform device\n",
 				__func__);
 		return -ENODEV;
 	}

 	return 0;
 }

 static int synaptics_rmi4_i2c_remove(struct i2c_client *client)
 {
 	platform_device_unregister(synaptics_dsx_i2c_device);

 	return 0;
 }

 static const struct i2c_device_id synaptics_rmi4_id_table[] = {
 	{I2C_DRIVER_NAME, 0},
 	{},
 };
 MODULE_DEVICE_TABLE(i2c, synaptics_rmi4_id_table);

 #ifdef CONFIG_OF
 static struct of_device_id synaptics_rmi4_of_match_table[] = {
 	{
 		.compatible = "synaptics,dsx-i2c",
 	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, synaptics_rmi4_of_match_table);
 #else
 #define synaptics_rmi4_of_match_table NULL
 #endif

 static struct i2c_driver synaptics_rmi4_i2c_driver = {
 	.driver = {
 		.name = I2C_DRIVER_NAME,
 		.owner = THIS_MODULE,
 		.of_match_table = synaptics_rmi4_of_match_table,
 	},
 	.probe = synaptics_rmi4_i2c_probe,
 	.remove = synaptics_rmi4_i2c_remove,
 	.id_table = synaptics_rmi4_id_table,
 };

 int synaptics_rmi4_bus_init_v26(void)
 {
 	return i2c_add_driver(&synaptics_rmi4_i2c_driver);
 }
 EXPORT_SYMBOL(synaptics_rmi4_bus_init_v26);

 void synaptics_rmi4_bus_exit_v26(void)
 {
 	kfree(wr_buf);

 	i2c_del_driver(&synaptics_rmi4_i2c_driver);

 	return;
 }
 EXPORT_SYMBOL(synaptics_rmi4_bus_exit_v26);

 MODULE_AUTHOR("Synaptics, Inc.");
 MODULE_DESCRIPTION("Synaptics DSX I2C Bus Support Module");
 MODULE_LICENSE("GPL v2");
	/*
	* Synaptics DSX touchscreen driver
	*
	* Copyright (C) 2012-2015 Synaptics Incorporated. All rights reserved.
	*
	* Copyright (C) 2012 Alexandra Chin <alexandra.chin@tw.synaptics.com>
	* Copyright (C) 2012 Scott Lin <scott.lin@tw.synaptics.com>
	* Copyright (C) 2018 The Linux Foundation. All rights reserved.
	*
	* 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/kernel.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/i2c.h>
	#include <linux/delay.h>
	#include <linux/input.h>
	#include <linux/types.h>
	#include <linux/of_gpio.h>
	#include <linux/platform_device.h>
	#include <linux/input/synaptics_dsx_v2_6.h>
	#include "synaptics_dsx_core.h"

	#define SYN_I2C_RETRY_TIMES 10

	/*
	#define I2C_BURST_LIMIT 255
	*/

	#define XFER_MSGS_LIMIT 8

	static unsigned char *wr_buf;

	static struct synaptics_dsx_hw_interface hw_if;

	static struct platform_device *synaptics_dsx_i2c_device;

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

	bdata->irq_gpio = of_get_named_gpio_flags(np,
	"synaptics,irq-gpio", 0,
	(enum of_gpio_flags *)&bdata->irq_flags);

	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;

	bdata->resume_in_workqueue = of_property_read_bool(np,
	"synaptics,resume-in-workqueue");

	bdata->wakeup_gesture_en = of_property_read_bool(np,
	"synaptics,wakeup-gestures-en");

	bdata->dont_disable_regs = of_property_read_bool(np,
	"synaptics,do-not-disable-regulators");

	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);
	retval = of_property_read_u32(np, "synaptics,power-on-state",
	&value);
	if (retval < 0) {
	dev_err(dev, "%s: Unable to read synaptics,power-on-state property\n",
	__func__);
	return retval;
	} else {
	bdata->power_on_state = value;
	}
	} else {
	bdata->power_gpio = -1;
	}

	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) {
	dev_err(dev, "%s: Unable to read synaptics,power-delay-ms property\n",
	__func__);
	return retval;
	} else {
	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);
	retval = of_property_read_u32(np, "synaptics,reset-on-state",
	&value);
	if (retval < 0) {
	dev_err(dev, "%s: Unable to read synaptics,reset-on-state property\n",
	__func__);
	return retval;
	} else {
	bdata->reset_on_state = value;
	}
	retval = of_property_read_u32(np, "synaptics,reset-active-ms",
	&value);
	if (retval < 0) {
	dev_err(dev, "%s: Unable to read synaptics,reset-active-ms property\n",
	__func__);
	return retval;
	} else {
	bdata->reset_active_ms = value;
	}
	} else {
	bdata->reset_gpio = -1;
	}

	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) {
	dev_err(dev, "%s: Unable to read synaptics,reset-delay-ms property\n",
	__func__);
	return retval;
	} else {
	bdata->reset_delay_ms = value;
	}
	} else {
	bdata->reset_delay_ms = 0;
	}

	prop = of_find_property(np, "synaptics,max-y-for-2d", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,max-y-for-2d",
	&value);
	if (retval < 0) {
	dev_err(dev, "%s: Unable to read synaptics,max-y-for-2d property\n",
	__func__);
	return retval;
	} else {
	bdata->max_y_for_2d = value;
	}
	} else {
	bdata->max_y_for_2d = -1;
	}

	retval = of_property_read_u32(np, "synaptics,bus-lpm-cur-uA",
	&value);
	bdata->bus_lpm_cur_uA = retval < 0 ? 0 : value;

	bdata->swap_axes = of_property_read_bool(np, "synaptics,swap-axes");
	bdata->x_flip = of_property_read_bool(np, "synaptics,x-flip");
	bdata->y_flip = of_property_read_bool(np, "synaptics,y-flip");

	prop = of_find_property(np, "synaptics,ub-i2c-addr", NULL);
	if (prop && prop->length) {
	retval = of_property_read_u32(np, "synaptics,ub-i2c-addr",
	&value);
	if (retval < 0) {
	dev_err(dev, "%s: Unable to read synaptics,ub-i2c-addr property\n",
	__func__);
	return retval;
	} else {
	bdata->ub_i2c_addr = (unsigned short)value;
	}
	} else {
	bdata->ub_i2c_addr = -1;
	}

	prop = of_find_property(np, "synaptics,cap-button-codes", NULL);
	if (prop && prop->length) {
	bdata->cap_button_map->map = devm_kzalloc(dev,
	prop->length,
	GFP_KERNEL);
	if (!bdata->cap_button_map->map)
	return -ENOMEM;
	bdata->cap_button_map->nbuttons = prop->length / sizeof(u32);
	retval = of_property_read_u32_array(np,
	"synaptics,cap-button-codes",
	bdata->cap_button_map->map,
	bdata->cap_button_map->nbuttons);
	if (retval < 0) {
	bdata->cap_button_map->nbuttons = 0;
	bdata->cap_button_map->map = NULL;
	}
	} else {
	bdata->cap_button_map->nbuttons = 0;
	bdata->cap_button_map->map = NULL;
	}

	prop = of_find_property(np, "synaptics,vir-button-codes", NULL);
	if (prop && prop->length) {
	bdata->vir_button_map->map = devm_kzalloc(dev,
	prop->length,
	GFP_KERNEL);
	if (!bdata->vir_button_map->map)
	return -ENOMEM;
	bdata->vir_button_map->nbuttons = prop->length / sizeof(u32);
	bdata->vir_button_map->nbuttons /= 5;
	retval = of_property_read_u32_array(np,
	"synaptics,vir-button-codes",
	bdata->vir_button_map->map,
	bdata->vir_button_map->nbuttons * 5);
	if (retval < 0) {
	bdata->vir_button_map->nbuttons = 0;
	bdata->vir_button_map->map = NULL;
	}
	} else {
	bdata->vir_button_map->nbuttons = 0;
	bdata->vir_button_map->map = NULL;
	}

	return 0;
	}
	#endif

	static int synaptics_rmi4_i2c_alloc_buf(struct synaptics_rmi4_data *rmi4_data,
	unsigned int count)
	{
	static unsigned int buf_size;

	if (count > buf_size) {
	if (buf_size)
	kfree(wr_buf);
	wr_buf = kzalloc(count, GFP_KERNEL);
	if (!wr_buf) {
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: Failed to alloc mem for buffer\n",
	__func__);
	buf_size = 0;
	return -ENOMEM;
	}
	buf_size = count;
	}

	return 0;
	}

	static void synaptics_rmi4_i2c_check_addr(struct synaptics_rmi4_data *rmi4_data,
	struct i2c_client *i2c)
	{
	if (hw_if.board_data->ub_i2c_addr == -1)
	return;

	if (hw_if.board_data->i2c_addr == i2c->addr)
	hw_if.board_data->i2c_addr = hw_if.board_data->ub_i2c_addr;
	else
	hw_if.board_data->i2c_addr = i2c->addr;

	return;
	}

	static int synaptics_rmi4_i2c_set_page(struct synaptics_rmi4_data *rmi4_data,
	unsigned short addr)
	{
	int retval = 0;
	unsigned char retry;
	unsigned char buf[PAGE_SELECT_LEN];
	unsigned char page;
	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
	struct i2c_msg msg[1];

	msg[0].addr = hw_if.board_data->i2c_addr;
	msg[0].flags = 0;
	msg[0].len = PAGE_SELECT_LEN;
	msg[0].buf = buf;

	page = ((addr >> 8) & MASK_8BIT);
	buf[0] = MASK_8BIT;
	buf[1] = page;

	if (page != rmi4_data->current_page) {
	for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
	if (i2c_transfer(i2c->adapter, &msg[0], 1) == 1) {
	rmi4_data->current_page = page;
	retval = PAGE_SELECT_LEN;
	break;
	}
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: I2C retry %d\n",
	__func__, retry + 1);
	msleep(20);

	if (retry == SYN_I2C_RETRY_TIMES / 2) {
	synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
	msg[0].addr = hw_if.board_data->i2c_addr;
	}
	}
	} else {
	retval = PAGE_SELECT_LEN;
	}

	return retval;
	}

	static int synaptics_rmi4_i2c_read(struct synaptics_rmi4_data *rmi4_data,
	unsigned short addr, unsigned char *data, unsigned short length)
	{
	int retval;
	unsigned char retry;
	unsigned char buf;
	#ifdef I2C_BURST_LIMIT
	unsigned char ii;
	unsigned char rd_msgs = ((length - 1) / I2C_BURST_LIMIT) + 1;
	#else
	unsigned char rd_msgs = 1;
	#endif
	unsigned char index = 0;
	unsigned char xfer_msgs;
	unsigned char remaining_msgs;
	unsigned short i2c_addr;
	unsigned short data_offset = 0;
	unsigned short remaining_length = length;
	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
	struct i2c_adapter *adap = i2c->adapter;
	struct i2c_msg msg[XFER_MSGS_LIMIT + 1];

	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);

	retval = synaptics_rmi4_i2c_set_page(rmi4_data, addr);
	if (retval != PAGE_SELECT_LEN) {
	retval = -EIO;
	goto exit;
	}

	msg[0].addr = hw_if.board_data->i2c_addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = &buf;

	#ifdef I2C_BURST_LIMIT
	for (ii = 0; ii < (rd_msgs - 1); ii++) {
	msg[ii + 1].addr = hw_if.board_data->i2c_addr;
	msg[ii + 1].flags = I2C_M_RD;
	msg[ii + 1].len = I2C_BURST_LIMIT;
	msg[ii + 1].buf = &data[data_offset];
	data_offset += I2C_BURST_LIMIT;
	remaining_length -= I2C_BURST_LIMIT;
	}
	#endif

	msg[rd_msgs].addr = hw_if.board_data->i2c_addr;
	msg[rd_msgs].flags = I2C_M_RD;
	msg[rd_msgs].len = remaining_length;
	msg[rd_msgs].buf = &data[data_offset];

	buf = addr & MASK_8BIT;

	remaining_msgs = rd_msgs + 1;

	while (remaining_msgs) {
	if (remaining_msgs > XFER_MSGS_LIMIT)
	xfer_msgs = XFER_MSGS_LIMIT;
	else
	xfer_msgs = remaining_msgs;
	for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
	retval = i2c_transfer(adap, &msg[index], xfer_msgs);
	if (retval == xfer_msgs)
	break;

	dev_err(rmi4_data->pdev->dev.parent,
	"%s: I2C retry %d\n",
	__func__, retry + 1);
	msleep(20);

	if (retry == SYN_I2C_RETRY_TIMES / 2) {
	synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
	i2c_addr = hw_if.board_data->i2c_addr;
	msg[0].addr = i2c_addr;
	#ifdef I2C_BURST_LIMIT
	for (ii = 0; ii < (rd_msgs - 1); ii++)
	msg[ii + 1].addr = i2c_addr;
	#endif
	msg[rd_msgs].addr = i2c_addr;
	}
	}

	if (retry == SYN_I2C_RETRY_TIMES) {
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: I2C read over retry limit\n",
	__func__);
	retval = -EIO;
	goto exit;
	}

	remaining_msgs -= xfer_msgs;
	index += xfer_msgs;
	}

	retval = length;

	exit:
	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

	return retval;
	}

	static int synaptics_rmi4_i2c_write(struct synaptics_rmi4_data *rmi4_data,
	unsigned short addr, unsigned char *data, unsigned short length)
	{
	int retval;
	unsigned char retry;
	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);
	struct i2c_msg msg[1];

	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);

	retval = synaptics_rmi4_i2c_alloc_buf(rmi4_data, length + 1);
	if (retval < 0)
	goto exit;

	retval = synaptics_rmi4_i2c_set_page(rmi4_data, addr);
	if (retval != PAGE_SELECT_LEN) {
	retval = -EIO;
	goto exit;
	}

	msg[0].addr = hw_if.board_data->i2c_addr;
	msg[0].flags = 0;
	msg[0].len = length + 1;
	msg[0].buf = wr_buf;

	wr_buf[0] = addr & MASK_8BIT;
	retval = secure_memcpy(&wr_buf[1], length, &data[0], length, length);
	if (retval < 0) {
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: Failed to copy data\n",
	__func__);
	goto exit;
	}

	for (retry = 0; retry < SYN_I2C_RETRY_TIMES; retry++) {
	if (i2c_transfer(i2c->adapter, &msg[0], 1) == 1) {
	retval = length;
	break;
	}
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: I2C retry %d\n",
	__func__, retry + 1);
	msleep(20);

	if (retry == SYN_I2C_RETRY_TIMES / 2) {
	synaptics_rmi4_i2c_check_addr(rmi4_data, i2c);
	msg[0].addr = hw_if.board_data->i2c_addr;
	}
	}

	if (retry == SYN_I2C_RETRY_TIMES) {
	dev_err(rmi4_data->pdev->dev.parent,
	"%s: I2C write over retry limit\n",
	__func__);
	retval = -EIO;
	}

	exit:
	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

	return retval;
	}

	#if defined(CONFIG_SECURE_TOUCH_SYNAPTICS_DSX_V26)
	static int synaptics_rmi4_clk_prepare_enable(
	struct synaptics_rmi4_data *rmi4_data)
	{
	int ret;

	ret = clk_prepare_enable(rmi4_data->iface_clk);
	if (ret) {
	dev_err(rmi4_data->pdev->dev.parent,
	"error on clk_prepare_enable(iface_clk):%d\n", ret);
	return ret;
	}

	ret = clk_prepare_enable(rmi4_data->core_clk);
	if (ret) {
	clk_disable_unprepare(rmi4_data->iface_clk);
	dev_err(rmi4_data->pdev->dev.parent,
	"error clk_prepare_enable(core_clk):%d\n", ret);
	}
	return ret;
	}

	static void synaptics_rmi4_clk_disable_unprepare(
	struct synaptics_rmi4_data *rmi4_data)
	{
	clk_disable_unprepare(rmi4_data->core_clk);
	clk_disable_unprepare(rmi4_data->iface_clk);
	}

	static int synaptics_rmi4_i2c_get(struct synaptics_rmi4_data *rmi4_data)
	{
	int retval;
	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);

	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);
	retval = pm_runtime_get_sync(i2c->adapter->dev.parent);
	if (retval >= 0 && rmi4_data->core_clk != NULL &&
	rmi4_data->iface_clk != NULL) {
	retval = synaptics_rmi4_clk_prepare_enable(rmi4_data);
	if (retval)
	pm_runtime_put_sync(i2c->adapter->dev.parent);
	}
	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);

	return retval;
	}

	static void synaptics_rmi4_i2c_put(struct synaptics_rmi4_data *rmi4_data)
	{
	struct i2c_client *i2c = to_i2c_client(rmi4_data->pdev->dev.parent);

	mutex_lock(&rmi4_data->rmi4_io_ctrl_mutex);
	if (rmi4_data->core_clk != NULL && rmi4_data->iface_clk != NULL)
	synaptics_rmi4_clk_disable_unprepare(rmi4_data);
	pm_runtime_put_sync(i2c->adapter->dev.parent);
	mutex_unlock(&rmi4_data->rmi4_io_ctrl_mutex);
	}
	#endif

	static struct synaptics_dsx_bus_access bus_access = {
	.type = BUS_I2C,
	.read = synaptics_rmi4_i2c_read,
	.write = synaptics_rmi4_i2c_write,
	#if defined(CONFIG_SECURE_TOUCH_SYNAPTICS_DSX_V26)
	.get = synaptics_rmi4_i2c_get,
	.put = synaptics_rmi4_i2c_put,
	#endif
	};

	static void synaptics_rmi4_i2c_dev_release(struct device *dev)
	{
	kfree(synaptics_dsx_i2c_device);

	return;
	}

	static int synaptics_rmi4_i2c_probe(struct i2c_client *client,
	const struct i2c_device_id *dev_id)
	{
	int retval;

	if (!i2c_check_functionality(client->adapter,
	I2C_FUNC_SMBUS_BYTE_DATA)) {
	dev_err(&client->dev,
	"%s: SMBus byte data commands not supported by host\n",
	__func__);
	return -EIO;
	}

	synaptics_dsx_i2c_device = kzalloc(
	sizeof(struct platform_device),
	GFP_KERNEL);
	if (!synaptics_dsx_i2c_device) {
	dev_err(&client->dev,
	"%s: Failed to allocate memory for synaptics_dsx_i2c_device\n",
	__func__);
	return -ENOMEM;
	}

	#ifdef CONFIG_OF
	if (client->dev.of_node) {
	hw_if.board_data = devm_kzalloc(&client->dev,
	sizeof(struct synaptics_dsx_board_data),
	GFP_KERNEL);
	if (!hw_if.board_data) {
	dev_err(&client->dev,
	"%s: Failed to allocate memory for board data\n",
	__func__);
	return -ENOMEM;
	}
	hw_if.board_data->cap_button_map = devm_kzalloc(&client->dev,
	sizeof(struct synaptics_dsx_button_map),
	GFP_KERNEL);
	if (!hw_if.board_data->cap_button_map) {
	dev_err(&client->dev,
	"%s: Failed to allocate memory for 0D button map\n",
	__func__);
	return -ENOMEM;
	}
	hw_if.board_data->vir_button_map = devm_kzalloc(&client->dev,
	sizeof(struct synaptics_dsx_button_map),
	GFP_KERNEL);
	if (!hw_if.board_data->vir_button_map) {
	dev_err(&client->dev,
	"%s: Failed to allocate memory for virtual button map\n",
	__func__);
	return -ENOMEM;
	}
	parse_dt(&client->dev, hw_if.board_data);
	}
	#else
	hw_if.board_data = client->dev.platform_data;
	#endif

	hw_if.bus_access = &bus_access;
	hw_if.board_data->i2c_addr = client->addr;

	synaptics_dsx_i2c_device->name = PLATFORM_DRIVER_NAME;
	synaptics_dsx_i2c_device->id = 0;
	synaptics_dsx_i2c_device->num_resources = 0;
	synaptics_dsx_i2c_device->dev.parent = &client->dev;
	synaptics_dsx_i2c_device->dev.platform_data = &hw_if;
	synaptics_dsx_i2c_device->dev.release = synaptics_rmi4_i2c_dev_release;

	retval = platform_device_register(synaptics_dsx_i2c_device);
	if (retval) {
	dev_err(&client->dev,
	"%s: Failed to register platform device\n",
	__func__);
	return -ENODEV;
	}

	return 0;
	}

	static int synaptics_rmi4_i2c_remove(struct i2c_client *client)
	{
	platform_device_unregister(synaptics_dsx_i2c_device);

	return 0;
	}

	static const struct i2c_device_id synaptics_rmi4_id_table[] = {
	{I2C_DRIVER_NAME, 0},
	{},
	};
	MODULE_DEVICE_TABLE(i2c, synaptics_rmi4_id_table);

	#ifdef CONFIG_OF
	static struct of_device_id synaptics_rmi4_of_match_table[] = {
	{
	.compatible = "synaptics,dsx-i2c",
	},
	{},
	};
	MODULE_DEVICE_TABLE(of, synaptics_rmi4_of_match_table);
	#else
	#define synaptics_rmi4_of_match_table NULL
	#endif

	static struct i2c_driver synaptics_rmi4_i2c_driver = {
	.driver = {
	.name = I2C_DRIVER_NAME,
	.owner = THIS_MODULE,
	.of_match_table = synaptics_rmi4_of_match_table,
	},
	.probe = synaptics_rmi4_i2c_probe,
	.remove = synaptics_rmi4_i2c_remove,
	.id_table = synaptics_rmi4_id_table,
	};

	int synaptics_rmi4_bus_init_v26(void)
	{
	return i2c_add_driver(&synaptics_rmi4_i2c_driver);
	}
	EXPORT_SYMBOL(synaptics_rmi4_bus_init_v26);

	void synaptics_rmi4_bus_exit_v26(void)
	{
	kfree(wr_buf);

	i2c_del_driver(&synaptics_rmi4_i2c_driver);

	return;
	}
	EXPORT_SYMBOL(synaptics_rmi4_bus_exit_v26);

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