drivers/nfc/nfc-nci.c

/* Copyright (c) 2013, 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 version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * 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/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/spinlock.h>
#include <linux/poll.h>
#include <linux/of_gpio.h>
#include <linux/clk.h>
#include <linux/of_device.h>
#include <linux/regulator/consumer.h>
#include "nfc-nci.h"

struct qca199x_platform_data {
	unsigned int irq_gpio;
	unsigned int dis_gpio;
	unsigned int ven_gpio;
	unsigned int reg;
};

static struct of_device_id msm_match_table[] = {
	{.compatible = "qcom,nfc-nci"},
	{}
};

MODULE_DEVICE_TABLE(of, msm_match_table);

#define MAX_BUFFER_SIZE		(780)
/* Read data */
#define PACKET_HEADER_SIZE_NCI	(4)
#define PACKET_TYPE_NCI		(16)
#define MAX_PACKET_SIZE		(PACKET_HEADER_SIZE_NCI + 255)
#define MAX_QCA_REG		(116)

static int nfc_i2c_write(struct i2c_client *client, u8 *buf, int len);

struct qca199x_dev {
	wait_queue_head_t read_wq;
	struct mutex read_mutex;
	struct i2c_client *client;
	struct miscdevice qca199x_device;
	unsigned int irq_gpio;
	unsigned int dis_gpio;
	unsigned int ven_gpio;
	bool irq_enabled;
	spinlock_t irq_enabled_lock;
	unsigned int count_irq;
	enum	nfcc_state	state;
};

/*
 * To allow filtering of nfc logging from user. This is set via
 * IOCTL NFC_KERNEL_LOGGING_MODE.
 */
static int logging_level;
/*
 * FTM-RAW-I2C RD/WR MODE
 */
static struct	devicemode	device_mode;
static int	ftm_raw_write_mode;
static int	ftm_werr_code;

static void qca199x_init_stat(struct qca199x_dev *qca199x_dev)
{
	qca199x_dev->count_irq = 0;
}

static void qca199x_disable_irq(struct qca199x_dev *qca199x_dev)
{
	unsigned long flags;

	spin_lock_irqsave(&qca199x_dev->irq_enabled_lock, flags);
	if (qca199x_dev->irq_enabled) {
		disable_irq_nosync(qca199x_dev->client->irq);
		qca199x_dev->irq_enabled = false;
	}
	spin_unlock_irqrestore(&qca199x_dev->irq_enabled_lock, flags);
}

static void qca199x_enable_irq(struct qca199x_dev *qca199x_dev)
{
	unsigned long flags;

	spin_lock_irqsave(&qca199x_dev->irq_enabled_lock, flags);
	if (!qca199x_dev->irq_enabled) {
		qca199x_dev->irq_enabled = true;
		enable_irq(qca199x_dev->client->irq);
	}
	spin_unlock_irqrestore(&qca199x_dev->irq_enabled_lock, flags);
}

static irqreturn_t qca199x_dev_irq_handler(int irq, void *dev_id)
{
	struct qca199x_dev *qca199x_dev = dev_id;
	unsigned long flags;

	spin_lock_irqsave(&qca199x_dev->irq_enabled_lock, flags);
	qca199x_dev->count_irq++;
	spin_unlock_irqrestore(&qca199x_dev->irq_enabled_lock, flags);
	wake_up(&qca199x_dev->read_wq);

	return IRQ_HANDLED;
}

static unsigned int nfc_poll(struct file *filp, poll_table *wait)
{
	struct qca199x_dev *qca199x_dev = filp->private_data;
	unsigned int mask = 0;
	unsigned long flags;

	poll_wait(filp, &qca199x_dev->read_wq, wait);

	spin_lock_irqsave(&qca199x_dev->irq_enabled_lock, flags);
	if (qca199x_dev->count_irq > 0) {
		qca199x_dev->count_irq--;
		mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_irqrestore(&qca199x_dev->irq_enabled_lock, flags);

	return mask;
}

/*
 * ONLY for FTM-RAW-I2C Mode
 * Required to instigate a read, which comes from DT layer. This means we need
 * to spoof an interrupt and send a wake up event.
 */
void ftm_raw_trigger_read(struct qca199x_dev *qca199x_dev)
{
	unsigned long flags;

	spin_lock_irqsave(&qca199x_dev->irq_enabled_lock, flags);
	qca199x_dev->count_irq++;
	spin_unlock_irqrestore(&qca199x_dev->irq_enabled_lock, flags);
	wake_up(&qca199x_dev->read_wq);
}

static ssize_t nfc_read(struct file *filp, char __user *buf,
					size_t count, loff_t *offset)
{
	struct qca199x_dev *qca199x_dev = filp->private_data;
	unsigned char tmp[MAX_BUFFER_SIZE], rd_byte;
	unsigned char len[PAYLOAD_HEADER_LENGTH];
	int total, length, ret;
	int ftm_rerr_code;
	enum ehandler_mode dmode;

	total = 0;
	length = 0;
	if (count > MAX_BUFFER_SIZE)
		count = MAX_BUFFER_SIZE;

	mutex_lock(&qca199x_dev->read_mutex);
	dmode = device_mode.handle_flavour;
	/* FTM-RAW-I2C RD/WR MODE - Special Case */
	if ((dmode == UNSOLICITED_FTM_RAW_MODE) ||
		(dmode == SOLICITED_FTM_RAW_MODE)) {
		/* READ */
		if ((ftm_raw_write_mode == 0) && (ftm_werr_code == 0)) {
			ftm_rerr_code = i2c_master_recv(qca199x_dev->client,
						&rd_byte, 1);
			if (ftm_rerr_code == 0x1)
				ftm_rerr_code = 0;
			tmp[0] = (unsigned char)ftm_rerr_code;
			tmp[1] = rd_byte;
			total  = 2;
			ret = copy_to_user(buf, tmp, total);
		}
		/* WRITE */
		else if ((ftm_raw_write_mode == 1) || (ftm_werr_code != 0)) {
			tmp[0] = (unsigned char)ftm_werr_code;
			total = 1;
			ret = copy_to_user(buf, tmp, total);
		} else {
			/* Invalid case */
			total = 0;
			ret = copy_to_user(buf, tmp, total);
		}
		mutex_unlock(&qca199x_dev->read_mutex);
		goto done;
	}

	/* NORMAL NCI Behaviour */
	/* Read the header */
	ret = i2c_master_recv(qca199x_dev->client, len, PAYLOAD_HEADER_LENGTH);
	if (ret != PAYLOAD_HEADER_LENGTH)
		goto err;
	length = len[PAYLOAD_HEADER_LENGTH - 1];

	/** make sure full packet fits in the buffer **/
	if ((length > 0) && ((length + PAYLOAD_HEADER_LENGTH) <= count)) {
		/* Read the packet */
		ret = i2c_master_recv(qca199x_dev->client, tmp, (length +
			PAYLOAD_HEADER_LENGTH));
		if (ret < 0)
			goto err;
		total = (length + PAYLOAD_HEADER_LENGTH);
	}
	mutex_unlock(&qca199x_dev->read_mutex);
	if (total > 0) {
		if ((total > count) || copy_to_user(buf, tmp, total)) {
			dev_err(&qca199x_dev->client->dev,
				"failed to copy to user space, total = %d\n",
					total);
			total = -EFAULT;
		}
	}
err:
	if (ret < 0)
		mutex_unlock(&qca199x_dev->read_mutex);
done:
	return total;
}

static ssize_t nfc_write(struct file *filp, const char __user *buf,
				size_t count, loff_t *offset)
{
	struct qca199x_dev *qca199x_dev = filp->private_data;
	char tmp[MAX_BUFFER_SIZE];
	int ret = 0;
	enum ehandler_mode dmode;

	if (count > MAX_BUFFER_SIZE) {
		dev_err(&qca199x_dev->client->dev, "out of memory\n");
		return -ENOMEM;
	}
	if (copy_from_user(tmp, buf, count)) {
		dev_err(&qca199x_dev->client->dev,
			"nfc-nci write: failed to copy from user space\n");
		return -EFAULT;
	}
	mutex_lock(&qca199x_dev->read_mutex);
	dmode = device_mode.handle_flavour;
	/* FTM-DIRECT-I2C RD/WR MODE */
	/* This is a special FTM-i2c mode case,where tester is not using NCI */
	if ((dmode == UNSOLICITED_FTM_RAW_MODE) ||
		(dmode == SOLICITED_FTM_RAW_MODE)) {
		/* Read From Register */
		if (count == 1) {
			ftm_raw_write_mode = 0;
			ret = i2c_master_send(qca199x_dev->client, tmp, count);
			if (ret == 1)
				ftm_werr_code = 0;
			else
				ftm_werr_code = ret;
			ftm_raw_trigger_read(qca199x_dev);
		}
		/* Write to Register */
		if (count == 2) {
			ftm_raw_write_mode = 1;
			ret = i2c_master_send(qca199x_dev->client, tmp, count);
			if (ret == 2)
				ftm_werr_code = 0;
			else
				ftm_werr_code = ret;
			ftm_raw_trigger_read(qca199x_dev);
		}
	} else {
		/* NORMAL NCI behaviour - NB :
		We can be in FTM mode here also */
		ret = i2c_master_send(qca199x_dev->client, tmp, count);
	}
	if (ret != count) {
		dev_err(&qca199x_dev->client->dev,
		"NFC: failed to write %d\n", ret);
		ret = -EIO;
	}
	mutex_unlock(&qca199x_dev->read_mutex);

	return ret;
}

static int nfc_open(struct inode *inode, struct file *filp)
{
	int ret = 0;

	struct qca199x_dev *qca199x_dev = container_of(filp->private_data,
							struct qca199x_dev,
							qca199x_device);

	filp->private_data = qca199x_dev;
	qca199x_init_stat(qca199x_dev);
	qca199x_enable_irq(qca199x_dev);
	dev_dbg(&qca199x_dev->client->dev,
			"%d,%d\n", imajor(inode), iminor(inode));
	return ret;
}

/*
 * Wake/Sleep Mode
 */
int nfcc_wake(int level, struct file *filp)
{
	int r = 0;
	unsigned char raw_nci_sleep[] = {0x2F, 0x03, 0x00};
	/* Change slave address to 0xE */
	unsigned char raw_nci_wake[]  = {0x10, 0x0F};
	unsigned short	slave_addr	=	0xE;
	unsigned short	curr_addr;
	struct qca199x_dev *qca199x_dev = filp->private_data;

	dev_dbg(&qca199x_dev->client->dev, "nfcc_wake: %s: info: %p\n",
			__func__, qca199x_dev);

	if (level == NFCC_SLEEP) {
		r = i2c_master_send(qca199x_dev->client, &raw_nci_sleep[0],
						sizeof(raw_nci_sleep));

		r = sizeof(raw_nci_sleep);
		if (r != sizeof(raw_nci_sleep))
			return -EMSGSIZE;
		qca199x_dev->state = NFCC_STATE_NORMAL_SLEEP;
	} else {
		curr_addr = qca199x_dev->client->addr;
		qca199x_dev->client->addr = slave_addr;
		r = nfc_i2c_write(qca199x_dev->client, &raw_nci_wake[0],
						sizeof(raw_nci_wake));
		/* Restore original NFCC slave I2C address */
		qca199x_dev->client->addr = curr_addr;
		r = sizeof(raw_nci_wake);
		if (r != sizeof(raw_nci_wake))
			return -EMSGSIZE;
		qca199x_dev->state = NFCC_STATE_NORMAL_WAKE;
	}

	return r;
}

/*
 * Inside nfc_ioctl_power_states
 *
 * @brief   ioctl functions
 *
 *
 * Device control
 * remove control via ioctl
 * (arg = 0): NFC_DISABLE   GPIO = 0
 * (arg = 1): NFC_DISABLE   GPIO = 1
 *  NOT USED   (arg = 2): FW_DL GPIO = 0
 *  NOT USED   (arg = 3): FW_DL GPIO = 1
 * (arg = 4): NFCC_WAKE  = 1
 * (arg = 5): NFCC_WAKE  = 0
 *
 *
 */
int nfc_ioctl_power_states(struct file *filp, unsigned int cmd,
							unsigned long arg)
{
	int r = 0;
	struct qca199x_dev *qca199x_dev = filp->private_data;

	if (arg == 0) {
		gpio_set_value(qca199x_dev->dis_gpio, 0);
		r = gpio_direction_output(qca199x_dev->dis_gpio, 1);
		if (r) {
			dev_err(&qca199x_dev->client->dev,
					"unable to set direction for gpio [%d]\n",
					qca199x_dev->dis_gpio);
			goto err_req;
		}
		gpio_set_value(qca199x_dev->dis_gpio, 0);
	} else if (arg == 1) {
		gpio_set_value(qca199x_dev->dis_gpio, 0);
		r = gpio_direction_output(qca199x_dev->dis_gpio, 1);
		if (r) {
			dev_err(&qca199x_dev->client->dev,
					"unable to set direction for gpio [%d]\n",
					qca199x_dev->dis_gpio);
			goto err_req;
		}
		gpio_set_value(qca199x_dev->dis_gpio, 1);
	} else if (arg == 2) {
		msleep(20);
	} else if (arg == 3) {
		msleep(20);
	} else if (arg == 4) {
		nfcc_wake(NFCC_WAKE, filp);
	} else if (arg == 5) {
		nfcc_wake(NFCC_SLEEP, filp);
	} else {
		r = -ENOIOCTLCMD;
	}

err_req:
	return r;
}


/*
 * Inside nfc_ioctl_nfcc_mode
 *
 * @brief   nfc_ioctl_nfcc_mode
 *
 * (arg = 0) ; NORMAL_MODE - Standard mode, unsolicited read behaviour
 * (arg = 1) ; SOLICITED_MODE - As above but reads are solicited from User Land
 * (arg = 2) ; UNSOLICITED_FTM_RAW MODE - NORMAL_MODE but messages from FTM and
 *             not NCI Host.
 * (arg = 2) ; SOLICITED_FTM_RAW_MODE - As SOLICITED_MODE but messages from FTM
 *             and not NCI Host.
 *
 *
 *
 */
int nfc_ioctl_nfcc_mode(struct file *filp, unsigned int cmd, unsigned long arg)
{
	int retval = 0;

	static unsigned short nci_addr;
	struct qca199x_dev *qca199x_dev = filp->private_data;
	struct qca199x_platform_data *platform_data;

	platform_data = qca199x_dev->client->dev.platform_data;

	if (arg == 0) {
		device_mode.handle_flavour = UNSOLICITED_MODE;
		qca199x_dev->client->addr = NCI_I2C_SLAVE;
		/* enable interrupts again */
		qca199x_enable_irq(qca199x_dev);
	} else if (arg == 1) {
		device_mode.handle_flavour = SOLICITED_MODE;
		qca199x_dev->client->addr = qca199x_dev->client->addr;
		/* enable interrupts again */
		qca199x_enable_irq(qca199x_dev);
	} else if (arg == 2) {
		device_mode.handle_flavour = UNSOLICITED_FTM_RAW_MODE;
		nci_addr = qca199x_dev->client->addr;
		/* replace with new client slave address*/
		qca199x_dev->client->addr = 0xE;
		/* We also need to disable interrupts */
		qca199x_disable_irq(qca199x_dev);
	} else if (arg == 3) {
		device_mode.handle_flavour = SOLICITED_FTM_RAW_MODE;
		nci_addr = qca199x_dev->client->addr;
		/* replace with new client slave address*/
		qca199x_dev->client->addr = 0xE;
		/* We also need to disable interrupts */
		qca199x_disable_irq(qca199x_dev);
	} else {
		device_mode.handle_flavour = UNSOLICITED_MODE;
		qca199x_dev->client->addr = NCI_I2C_SLAVE;
	}
	return retval;
}

/*
 * Inside nfc_ioctl_kernel_logging
 *
 * @brief   nfc_ioctl_kernel_logging
 *
 * (arg = 0) ; NO_LOGGING
 * (arg = 1) ; COMMS_LOGGING - BASIC LOGGING - Mainly just comms over I2C
 * (arg = 2) ; FULL_LOGGING - ENABLE ALL  - DBG messages for handlers etc.
 *           ; ! Be aware as amount of logging could impact behaviour !
 *
 *
 */
int nfc_ioctl_kernel_logging(unsigned long arg,  struct file *filp)
{
	int retval = 0;
	struct qca199x_dev *qca199x_dev = container_of(filp->private_data,
							   struct qca199x_dev,
							   qca199x_device);
	if (arg == 0) {
		dev_dbg(&qca199x_dev->client->dev,
		"nfc_ioctl_kernel_logging : level = NO_LOGGING\n");
		logging_level = 0;
	} else if (arg == 1) {
		dev_dbg(&qca199x_dev->client->dev,
		"nfc_ioctl_kernel_logging: level = COMMS_LOGGING only\n");
		logging_level = 1;
	} else if (arg == 2) {
		dev_dbg(&qca199x_dev->client->dev,
		"nfc_ioctl_kernel_logging: level = FULL_LOGGING\n");
		logging_level = 2;
	}
	return retval;
}

static long nfc_ioctl(struct file *pfile, unsigned int cmd, unsigned long arg)
{
	int r = 0;

	switch (cmd) {

	case NFC_SET_PWR:
		nfc_ioctl_power_states(pfile, cmd, arg);
		break;
	case NFCC_MODE:
		nfc_ioctl_nfcc_mode(pfile, cmd, arg);
		break;
	case NFC_KERNEL_LOGGING_MODE:
		nfc_ioctl_kernel_logging(arg, pfile);
		break;
	case SET_RX_BLOCK:
		break;
	case SET_EMULATOR_TEST_POINT:
		break;
	default:
		r = -ENOIOCTLCMD;
	}
	return r;
}

static const struct file_operations nfc_dev_fops = {
	.owner = THIS_MODULE,
	.llseek = no_llseek,
	.poll  = nfc_poll,
	.read  = nfc_read,
	.write = nfc_write,
	.open = nfc_open,
	.unlocked_ioctl = nfc_ioctl
};

void dumpqca1990(struct i2c_client *client)
{
	int r = 0;
	int i = 0;
	unsigned char raw_reg_rd = {0x0};
	unsigned short temp_addr;

	temp_addr = client->addr;
	client->addr = 0x0E;

	for (i = 0; i < MAX_QCA_REG; i++) {
		raw_reg_rd = i;
		if (((i >= 0x0) && (i < 0x4)) || ((i > 0x7) && (i < 0xA)) ||
		((i > 0xF) && (i < 0x12)) || ((i > 0x39) && (i < 0x4d)) ||
		((i > 0x69) && (i < 0x74)) || (i == 0x18) || (i == 0x30) ||
		(i == 0x58)) {
			r = nfc_i2c_write(client, &raw_reg_rd, 1);
			msleep(20);
			r = i2c_master_recv(client, &raw_reg_rd, 1);
		}
	}
	client->addr = temp_addr;
}

static int nfc_i2c_write(struct i2c_client *client, u8 *buf, int len)
{
	int r;

	r = i2c_master_send(client, buf, len);
	dev_dbg(&client->dev, "send: %d\n", r);
	if (r == -EREMOTEIO) { /* Retry, chip was in standby */
		usleep_range(6000, 10000);
		r = i2c_master_send(client, buf, len);
		dev_dbg(&client->dev, "send2: %d\n", r);
	}
	if (r != len)
		return -EREMOTEIO;

	return r;
}

int nfcc_initialise(struct i2c_client *client, unsigned short curr_addr)
{
	int r = 0;
	unsigned char raw_1p8_CONTROL_011[]	= {0x11, XTAL_CLOCK};
	unsigned char raw_1P8_CONTROL_010[]	= {0x10, PWR_EN};
	unsigned char raw_1P8_X0_0B0[]		= {0xB0, (FREQ_SEL)};
	unsigned char raw_slave1[]		= {0x09, NCI_I2C_SLAVE};
	unsigned char raw_slave2[]		= {0x8, 0x10};
	unsigned char raw_s73[]			= {0x73, 0x02};
	unsigned char raw_slave1_rd		= {0x0};
	unsigned char raw_1P8_PAD_CFG_CLK_REQ[]	= {0xA5, 0x1};
	unsigned char raw_1P8_PAD_CFG_PWR_REQ[]	= {0xA7, 0x1};
	unsigned char buf = 0;

	client->addr = curr_addr;
	r = i2c_master_send(client, &buf, 1);
	buf = 0;
	r = i2c_master_recv(client, &buf, 1);
	if (0x10 != (0x10 & buf)) {
		RAW(s73, 0x02);

		r = nfc_i2c_write(client, &raw_s73[0], sizeof(raw_s73));
		usleep(1000);
		RAW(1p8_CONTROL_011, XTAL_CLOCK | 0x01);

		r = nfc_i2c_write(client, &raw_1p8_CONTROL_011[0],
						sizeof(raw_1p8_CONTROL_011));
		usleep(1000);
		RAW(1P8_CONTROL_010, (0x8));
		r = nfc_i2c_write(client, &raw_1P8_CONTROL_010[0],
						sizeof(raw_1P8_CONTROL_010));

		usleep(10000);  /* 10ms wait */
		RAW(1P8_CONTROL_010, (0xC));
		r = nfc_i2c_write(client, &raw_1P8_CONTROL_010[0],
					sizeof(raw_1P8_CONTROL_010));
		usleep(100);  /* 100uS wait */
		RAW(1P8_X0_0B0, (FREQ_SEL_19));
		r = nfc_i2c_write(client, &raw_1P8_X0_0B0[0],
						sizeof(raw_1P8_X0_0B0));
		usleep(1000);

		/* PWR_EN = 1 */
		RAW(1P8_CONTROL_010, (0xd));
		r = nfc_i2c_write(client, &raw_1P8_CONTROL_010[0],
						sizeof(raw_1P8_CONTROL_010));
		usleep(20000);  /* 20ms wait */
		/* LS_EN = 1 */
		RAW(1P8_CONTROL_010, 0xF);
		r = nfc_i2c_write(client, &raw_1P8_CONTROL_010[0],
						sizeof(raw_1P8_CONTROL_010));
		usleep(20000);  /* 20ms wait */

		/* Enable the PMIC clock */
		RAW(1P8_PAD_CFG_CLK_REQ, (0x1));
		r = nfc_i2c_write(client, &raw_1P8_PAD_CFG_CLK_REQ[0],
					  sizeof(raw_1P8_PAD_CFG_CLK_REQ));
		usleep(1000);

		RAW(1P8_PAD_CFG_PWR_REQ, (0x1));
		r = nfc_i2c_write(client, &raw_1P8_PAD_CFG_PWR_REQ[0],
					  sizeof(raw_1P8_PAD_CFG_PWR_REQ));
		usleep(1000);

		RAW(slave2, 0x10);
		r = nfc_i2c_write(client, &raw_slave2[0], sizeof(raw_slave2));
		usleep(1000);

		RAW(slave1, NCI_I2C_SLAVE);
		r = nfc_i2c_write(client, &raw_slave1[0], sizeof(raw_slave1));
		usleep(1000);

		/* QCA199x NFCC CPU should now boot... */
		r = i2c_master_recv(client, &raw_slave1_rd, 1);
		/* Talk on NCI slave address NCI_I2C_SLAVE 0x2C*/
		client->addr = NCI_I2C_SLAVE;
		r = 0;
	} else {
		r = 1;
	}
	return r;
}

static int nfc_parse_dt(struct device *dev, struct qca199x_platform_data *pdata)
{
	int r = 0;
	struct device_node *np = dev->of_node;

	r = of_property_read_u32(np, "reg", &pdata->reg);
	if (r)
		return -EINVAL;

	r = of_property_read_u32(np, "qcom,clk-gpio", &pdata->ven_gpio);
	if (r)
		return -EINVAL;

	pdata->dis_gpio = of_get_named_gpio(np, "qcom,dis-gpio", 0);
	if ((!gpio_is_valid(pdata->dis_gpio)))
		return -EINVAL;

	pdata->irq_gpio = of_get_named_gpio(np, "qcom,irq-gpio", 0);
	if ((!gpio_is_valid(pdata->irq_gpio)))
		return -EINVAL;

	return r;
}

static int qca199x_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int r = 0;
	int irqn = 0;
	struct clk *nfc_clk;
	struct device_node *node = client->dev.of_node;
	struct qca199x_platform_data *platform_data;
	struct qca199x_dev *qca199x_dev;

	if (client->dev.of_node) {
		platform_data = devm_kzalloc(&client->dev,
			sizeof(struct qca199x_platform_data), GFP_KERNEL);
		if (!platform_data) {
			dev_err(&client->dev,
			"nfc-nci probe: Failed to allocate memory\n");
			return -ENOMEM;
		}
		r = nfc_parse_dt(&client->dev, platform_data);
		if (r)
			return r;
	} else {
		platform_data = client->dev.platform_data;
	}
	if (!platform_data)
		return -EINVAL;
	dev_dbg(&client->dev,
		"nfc-nci probe: %s, inside nfc-nci flags = %x\n",
		__func__, client->flags);
	if (platform_data == NULL) {
		dev_err(&client->dev, "nfc-nci probe: failed\n");
		return -ENODEV;
	}
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
		dev_err(&client->dev, "nfc-nci probe: need I2C_FUNC_I2C\n");
		return -ENODEV;
	}
	qca199x_dev = kzalloc(sizeof(*qca199x_dev), GFP_KERNEL);
	if (qca199x_dev == NULL) {
		dev_err(&client->dev,
		"nfc-nci probe: failed to allocate memory for module data\n");
		return -ENOMEM;
	}
	if (gpio_is_valid(platform_data->irq_gpio)) {
		r = gpio_request(platform_data->irq_gpio, "nfc_irq_gpio");
		if (r) {
			dev_err(&client->dev, "unable to request gpio [%d]\n",
				platform_data->irq_gpio);
			goto err_irq;
		}
		r = gpio_direction_input(platform_data->irq_gpio);
		if (r) {

			dev_err(&client->dev,
			"unable to set direction for gpio [%d]\n",
				platform_data->irq_gpio);
			goto err_irq;
		}
		gpio_to_irq(0);
		irqn = gpio_to_irq(platform_data->irq_gpio);
		if (irqn < 0) {
			r = irqn;
			goto err_irq;
		}
		client->irq = irqn;

	} else {
		dev_err(&client->dev, "irq gpio not provided\n");
		goto err_free_dev;
	}
	if (gpio_is_valid(platform_data->dis_gpio)) {
		r = gpio_request(platform_data->dis_gpio, "nfc_reset_gpio");
		if (r) {
			dev_err(&client->dev,
			"NFC: unable to request gpio [%d]\n",
				platform_data->dis_gpio);
			goto err_dis_gpio;
		}
		r = gpio_direction_output(platform_data->dis_gpio, 1);
		if (r) {
			dev_err(&client->dev,
				"NFC: unable to set direction for gpio [%d]\n",
					platform_data->dis_gpio);
			goto err_dis_gpio;
		}
	} else {
		dev_err(&client->dev, "dis gpio not provided\n");
		goto err_irq;
	}
	gpio_set_value(qca199x_dev->dis_gpio, 1);
	msleep(20);
	gpio_set_value(qca199x_dev->dis_gpio, 0);

	nfc_clk  = clk_get(&client->dev, "ref_clk");

	if (nfc_clk == NULL)
		goto err_dis_gpio;

	r = clk_prepare_enable(nfc_clk);
	if (r)
		goto err_dis_gpio;

	platform_data->ven_gpio = of_get_named_gpio(node,
						"qcom,clk-gpio", 0);

	if (gpio_is_valid(platform_data->ven_gpio)) {
		r = gpio_request(platform_data->ven_gpio, "nfc_ven_gpio");
		if (r) {
			dev_err(&client->dev, "unable to request gpio [%d]\n",
						platform_data->ven_gpio);
			goto err_ven_gpio;
		}
		r = gpio_direction_input(platform_data->ven_gpio);
		if (r) {

			dev_err(&client->dev,
			"unable to set direction for gpio [%d]\n",
						platform_data->ven_gpio);
			goto err_ven_gpio;
		}

	} else {

		dev_err(&client->dev, "ven gpio not provided\n");
		goto err_dis_gpio;
	}
	qca199x_dev->dis_gpio = platform_data->dis_gpio;
	qca199x_dev->irq_gpio = platform_data->irq_gpio;
	qca199x_dev->ven_gpio = platform_data->ven_gpio;
	qca199x_dev->client = client;

	/* init mutex and queues */
	init_waitqueue_head(&qca199x_dev->read_wq);
	mutex_init(&qca199x_dev->read_mutex);
	spin_lock_init(&qca199x_dev->irq_enabled_lock);

	qca199x_dev->qca199x_device.minor = MISC_DYNAMIC_MINOR;
	qca199x_dev->qca199x_device.name = "nfc-nci";
	qca199x_dev->qca199x_device.fops = &nfc_dev_fops;

	r = misc_register(&qca199x_dev->qca199x_device);
	if (r) {
		dev_err(&client->dev, "misc_register failed\n");
		goto err_misc_register;
	}

	logging_level = 0;
	/* request irq.  The irq is set whenever the chip has data available
	* for reading.  It is cleared when all data has been read.
	*/
	device_mode.handle_flavour = UNSOLICITED_MODE;
	r = nfcc_initialise(client, platform_data->reg);
	if (r) {
		dev_err(&client->dev, "nfc-nci probe: request nfcc initialise failed\n");
		goto err_nfcc_init_failed;
	}

	qca199x_dev->irq_enabled = true;
	r = request_irq(client->irq, qca199x_dev_irq_handler,
			  IRQF_TRIGGER_RISING, client->name, qca199x_dev);
	if (r) {
		dev_err(&client->dev, "nfc-nci probe: request_irq failed\n");
		goto err_request_irq_failed;
	}
	qca199x_disable_irq(qca199x_dev);
	i2c_set_clientdata(client, qca199x_dev);
	dev_dbg(&client->dev,
	"nfc-nci probe: %s, probing qca1990 exited successfully\n",
		 __func__);
	return 0;

err_nfcc_init_failed:
err_request_irq_failed:
	misc_deregister(&qca199x_dev->qca199x_device);
err_misc_register:
	mutex_destroy(&qca199x_dev->read_mutex);
err_ven_gpio:
	gpio_free(platform_data->ven_gpio);
err_dis_gpio:
	gpio_free(platform_data->dis_gpio);
err_irq:
	gpio_free(platform_data->irq_gpio);
err_free_dev:
	kfree(qca199x_dev);
	return r;
}

static int qca199x_remove(struct i2c_client *client)
{
	struct qca199x_dev *qca199x_dev;

	qca199x_dev = i2c_get_clientdata(client);
	free_irq(client->irq, qca199x_dev);
	misc_deregister(&qca199x_dev->qca199x_device);
	mutex_destroy(&qca199x_dev->read_mutex);
	gpio_free(qca199x_dev->irq_gpio);
	gpio_free(qca199x_dev->dis_gpio);
	gpio_free(qca199x_dev->ven_gpio);
	kfree(qca199x_dev);

	return 0;
}

static const struct i2c_device_id qca199x_id[] = {
	{"qca199x-i2c", 0},
	{}
};

static struct i2c_driver qca199x = {
	.id_table = qca199x_id,
	.probe = qca199x_probe,
	.remove = qca199x_remove,
	.driver = {
		.owner = THIS_MODULE,
		.name = "nfc-nci",
		.of_match_table = msm_match_table,
	},
};

/*
 * module load/unload record keeping
 */
static int __init qca199x_dev_init(void)
{
	return i2c_add_driver(&qca199x);
}
module_init(qca199x_dev_init);

static void __exit qca199x_dev_exit(void)
{
	i2c_del_driver(&qca199x);
}
module_exit(qca199x_dev_exit);

MODULE_DESCRIPTION("NFC QCA199x");
MODULE_LICENSE("GPL v2");