NFC: add NQxxxx driver

Add new NCI driver with support for NQxxxx controller.

This is a character device driver. It enables control of the
NQx NFC controller using the i2c bus and GPIOs.

Change-Id: I807273821dc3405813b3ef2bf02f41a478293f43
Acked-by: Afroditi Ilioudi <ailioudi@qti.qualcomm.com>
Signed-off-by: Puneet Mishra <puneetm@codeaurora.org>

Documentation/devicetree/bindings/nfc/nq-nci.txt

@@ -0,0 +1,43 @@
+Qualcomm Technologies, Inc NQxxxx NFC NCI device
+
+Near Field Communication (NFC) device is based on NFC Controller Interface (NCI)
+
+Required properties:
+
+- compatible: "qcom,nq-nci"
+- reg: NCI i2c slave address.
+- qcom,nq-ven: specific gpio for hardware reset.
+- qcom,nq-irq: specific gpio for read interrupt.
+- interrupt-parent: Should be phandle for the interrupt controller
+                    that services interrupts for this device.
+- interrupts: Nfc read interrupt,gpio-clk-req interrupt
+
+
+Recommended properties:
+
+- interrupt-names: names of interrupts, should include "nfc_irq", used for reference
+
+
+Optional properties:
+
+- pinctrl-names, pinctrl-0, pincntrl-1: references to our pincntrl settings
+- clocks, clock-names: must contain the NQxxxx's core clock.
+
+Example:
+
+	nq-nci@2b {
+		compatible = "qcom,nq-nci";
+		reg = <0x2b>;
+		qcom,irq-gpio = <&msm_gpio 29 0x00>;
+		qcom,en-gpio = <&msm_gpio 30 0x00>;
+		qcom,clk-src = "BBCLK2";
+		interrupt-parent = <&msm_gpio>;
+		interrupts = <29 0>;
+		interrupt-names = "nfc_irq";
+		pinctrl-names = "nfc_active","nfc_suspend";
+		pinctrl-0 = <&nfc_int_active &nfc_disable_active>;
+		pinctrl-1 = <&nfc_int_suspend &nfc_disable_suspend>;
+		qcom,clk-gpio = <&pm8916_gpios 2 0>;
+		clocks = <&clock_rpm clk_bb_clk2_pin>;
+		clock-names = "ref_clk";
+	};

drivers/nfc/Kconfig

@@ -49,3 +49,12 @@ config NFC_QNCI
 	  This enables the NFC driver for QCA199x based devices.
 	  This is for i2c connected version. NCI protocol logic
 	  resides in the usermode and it has no other NFC dependencies.
+
+config NFC_NQ
+	bool "Qualcomm NCI based NFC Controller Driver for NQx"
+	depends on I2C
+	select CRC_CCITT
+	help
+	  This enables the NFC driver for NQx based devices.
+	  This is for i2c connected version. NCI protocol logic
+	  resides in the usermode and it has no other NFC dependencies.

drivers/nfc/Makefile

@@ -8,5 +8,6 @@ obj-$(CONFIG_NFC_PN533)		+= pn533.o
 obj-$(CONFIG_NFC_WILINK)	+= nfcwilink.o
 obj-$(CONFIG_NFC_MEI_PHY)	+= mei_phy.o
 obj-$(CONFIG_NFC_QNCI)		+= nfc-nci.o
+obj-$(CONFIG_NFC_NQ)		+= nq-nci.o
 
 ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG

drivers/nfc/nq-nci.c

@@ -0,0 +1,693 @@
+/* Copyright (c) 2015, 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/reboot.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/spinlock.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
+#include <linux/uaccess.h>
+#include "nq-nci.h"
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+#endif
+
+struct nqx_platform_data {
+	unsigned int irq_gpio;
+	unsigned int dis_gpio;
+	unsigned int clkreq_gpio;
+	const char *clk_src_name;
+};
+
+static struct of_device_id msm_match_table[] = {
+	{.compatible = "qcom,nq-nci"},
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, msm_match_table);
+#define MAX_BUFFER_SIZE			(320)
+#define PACKET_MAX_LENGTH		(258)
+/* Read data */
+#define PACKET_HEADER_SIZE_NCIPACKET_HEADER_SIZE_NCI	(4)
+#define MAX_PACKET_SIZE			(PACKET_HEADER_SIZE_NCI + 255)
+/* will timeout in approx. 100ms as 10us steps */
+#define NTF_TIMEOUT				(100)
+#define	CORE_RESET_RSP_GID		(0x60)
+#define	CORE_RESET_OID			(0x00)
+#define CORE_RST_NTF_LENGTH		(0x02)
+#define WAKEUP_SRC_TIMEOUT		(2000)
+
+struct nqx_dev {
+	wait_queue_head_t	read_wq;
+	struct	mutex		read_mutex;
+	struct	i2c_client	*client;
+	struct	miscdevice	nqx_device;
+	unsigned int		irq_gpio;
+	unsigned int		dis_gpio;
+	unsigned int		clkreq_gpio;
+	/* NFC_IRQ state */
+	bool			irq_enabled;
+	spinlock_t		irq_enabled_lock;
+	unsigned int		count_irq;
+	/* CLK control */
+	unsigned int		core_reset_ntf;
+	bool			clk_run;
+};
+
+static int nfcc_reboot(struct notifier_block *notifier, unsigned long val,
+			void *v);
+
+static struct notifier_block nfcc_notifier = {
+	.notifier_call	= nfcc_reboot,
+	.next			= NULL,
+	.priority		= 0
+};
+
+unsigned int	disable_ctrl;
+
+static void nqx_init_stat(struct nqx_dev *nqx_dev)
+{
+	nqx_dev->count_irq = 0;
+}
+
+static void nqx_disable_irq(struct nqx_dev *nqx_dev)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&nqx_dev->irq_enabled_lock, flags);
+	if (nqx_dev->irq_enabled) {
+		disable_irq_nosync(nqx_dev->client->irq);
+		nqx_dev->irq_enabled = false;
+	}
+	spin_unlock_irqrestore(&nqx_dev->irq_enabled_lock, flags);
+}
+
+static void nqx_enable_irq(struct nqx_dev *nqx_dev)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&nqx_dev->irq_enabled_lock, flags);
+	if (!nqx_dev->irq_enabled) {
+		nqx_dev->irq_enabled = true;
+		enable_irq(nqx_dev->client->irq);
+	}
+	spin_unlock_irqrestore(&nqx_dev->irq_enabled_lock, flags);
+}
+
+static irqreturn_t nqx_dev_irq_handler(int irq, void *dev_id)
+{
+	struct nqx_dev *nqx_dev = dev_id;
+	unsigned long flags;
+	int ret;
+
+	if (device_may_wakeup(&nqx_dev->client->dev) &&
+		(nqx_dev->client->dev.power.is_suspended == true)) {
+		pm_wakeup_event(&nqx_dev->client->dev, WAKEUP_SRC_TIMEOUT);
+	}
+	ret = gpio_get_value_cansleep(nqx_dev->irq_gpio);
+	if (!ret) {
+		dev_info(&nqx_dev->client->dev,
+			"nqx nfc : nqx_dev_irq_handler error = %d\n", ret);
+		return IRQ_HANDLED;
+	}
+
+	spin_lock_irqsave(&nqx_dev->irq_enabled_lock, flags);
+	nqx_dev->count_irq++;
+	spin_unlock_irqrestore(&nqx_dev->irq_enabled_lock, flags);
+	wake_up(&nqx_dev->read_wq);
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t nfc_read(struct file *filp, char __user *buf,
+					size_t count, loff_t *offset)
+{
+	struct nqx_dev *nqx_dev = filp->private_data;
+	unsigned char tmp[MAX_BUFFER_SIZE];
+	unsigned char len[PAYLOAD_HEADER_LENGTH];
+	int total, length, ret;
+
+	total = 0;
+	length = 0;
+	if (count > MAX_BUFFER_SIZE)
+		count = MAX_BUFFER_SIZE;
+
+	mutex_lock(&nqx_dev->read_mutex);
+
+	memset(tmp, 0, sizeof(tmp));
+	memset(len, 0, sizeof(len));
+	/* Read the header */
+	ret = i2c_master_recv(nqx_dev->client, len, PAYLOAD_HEADER_LENGTH);
+	/*
+	 * We ignore all packets of length PAYLOAD_HEADER_LENGTH
+	 * or less (i.e <=3). In this case return a total length
+	 * of ZERO. So ALL PACKETS MUST HAVE A PAYLOAD.
+	 * If ret < 0 then this is an error code.
+	 */
+	if (ret != PAYLOAD_HEADER_LENGTH) {
+		if (ret < 0)
+			total = ret;
+		else
+			total = 0;
+		goto err;
+	}
+	length = len[PAYLOAD_HEADER_LENGTH - 1];
+	if (length == 0) {
+		ret = 0;
+		total = ret;
+		goto err;
+	}
+	/** make sure full packet fits in the buffer **/
+	if ((length > 0) && ((length + PAYLOAD_HEADER_LENGTH) <= count)) {
+		/* Read the packet */
+		ret = i2c_master_recv(nqx_dev->client, tmp, (length +
+			PAYLOAD_HEADER_LENGTH));
+		total = ret;
+		if (ret < 0)
+			goto err;
+	}
+
+	dev_dbg(&nqx_dev->client->dev, "%s : NfcNciRx %x %x %x\n",
+			__func__, tmp[0], tmp[1], tmp[2]);
+	if (total > 0) {
+		if ((total > count) || copy_to_user(buf, tmp, total)) {
+			dev_err(&nqx_dev->client->dev,
+				"%s: failed to copy to user space, total = %d\n",
+					__func__, total);
+			total = -EFAULT;
+		}
+	}
+err:
+	mutex_unlock(&nqx_dev->read_mutex);
+	return total;
+}
+
+static ssize_t nfc_write(struct file *filp, const char __user *buf,
+				size_t count, loff_t *offset)
+{
+	struct nqx_dev *nqx_dev = filp->private_data;
+	char tmp[MAX_BUFFER_SIZE];
+	int ret = 0;
+	if (count > MAX_BUFFER_SIZE) {
+		dev_err(&nqx_dev->client->dev, "%s: out of memory\n",
+			__func__);
+		return -ENOMEM;
+	}
+	if (copy_from_user(tmp, buf, count)) {
+		dev_err(&nqx_dev->client->dev,
+			"%s: failed to copy from user space\n", __func__);
+		return -EFAULT;
+	}
+	mutex_lock(&nqx_dev->read_mutex);
+	ret = i2c_master_send(nqx_dev->client, tmp, count);
+	if (ret != count) {
+		dev_err(&nqx_dev->client->dev,
+		"%s: failed to write %d\n", __func__, ret);
+		ret = -EIO;
+	}
+	mutex_unlock(&nqx_dev->read_mutex);
+	dev_dbg(&nqx_dev->client->dev, "%s : NfcNciTx %x %x %x\n",
+			__func__, tmp[0], tmp[1], tmp[2]);
+	return ret;
+}
+
+static int nfc_open(struct inode *inode, struct file *filp)
+{
+	int ret = 0;
+	struct nqx_dev *nqx_dev = container_of(filp->private_data,
+				struct nqx_dev, nqx_device);
+
+	filp->private_data = nqx_dev;
+	nqx_init_stat(nqx_dev);
+	/* Enable interrupts from NFCC NFC_INT new NCI data available */
+	nqx_enable_irq(nqx_dev);
+
+	dev_dbg(&nqx_dev->client->dev,
+			"%s: %d,%d\n", __func__, imajor(inode), iminor(inode));
+	return ret;
+}
+
+/*
+ * 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
+ *
+ *
+ */
+int nfc_ioctl_power_states(struct file *filp, unsigned int cmd,
+							unsigned long arg)
+{
+	int r = 0;
+	struct nqx_dev *nqx_dev = filp->private_data;
+
+	if (arg == 0) {
+		dev_dbg(&nqx_dev->client->dev,
+			"gpio_set_value disable: %s: info: %p\n",
+			__func__, nqx_dev);
+		gpio_set_value(nqx_dev->dis_gpio, 0);
+		usleep_range(1000, 1100);
+	} else if (arg == 1) {
+		/*
+		 * We are attempting a hardware reset so let us disable
+		 * interrupts to avoid spurious notifications to upper
+		 * layers.
+		 */
+		nqx_disable_irq(nqx_dev);
+		dev_dbg(&nqx_dev->client->dev,
+			"gpio_set_value enable: %s: info: %p\n",
+			__func__, nqx_dev);
+		gpio_set_value(nqx_dev->dis_gpio, 1);
+		/* NFCC needs at least 100 ms to power cycle*/
+		msleep(100);
+	} else if (arg == 2) {
+		mutex_lock(&nqx_dev->read_mutex);
+		dev_dbg(&nqx_dev->client->dev,
+			"before nfcc_initialise: %s: info: %p\n",
+			__func__, nqx_dev);
+		dev_dbg(&nqx_dev->client->dev,
+			"after nfcc_initialise: %s: info: %p\n",
+			__func__, nqx_dev);
+		mutex_unlock(&nqx_dev->read_mutex);
+	} else if (arg == 3) {
+		msleep(20);
+	} else {
+		r = -ENOIOCTLCMD;
+	}
+	return r;
+}
+
+#ifdef CONFIG_COMPAT
+static long nfc_compat_ioctl(struct file *pfile, unsigned int cmd,
+				unsigned long arg)
+{
+	long r = 0;
+	arg = (compat_u64)arg;
+
+	switch (cmd) {
+	case NFC_SET_PWR:
+		nfc_ioctl_power_states(pfile, cmd, arg);
+		break;
+	case SET_RX_BLOCK:
+		break;
+	case SET_EMULATOR_TEST_POINT:
+		break;
+	default:
+		r = -ENOTTY;
+	}
+	return r;
+}
+#endif
+
+/*
+ * Inside nfc_ioctl_core_reset_ntf
+ *
+ * @brief	nfc_ioctl_core_reset_ntf
+ *
+ * Allows callers to determine if a CORE_RESET_NTF has arrived
+ *
+ * Returns the value of variable core_reset_ntf
+ *
+ */
+int nfc_ioctl_core_reset_ntf(struct file *filp, unsigned int cmd,
+				unsigned long arg)
+{
+	struct nqx_dev *nqx_dev = filp->private_data;
+	dev_dbg(&nqx_dev->client->dev, "%s: returning = %d\n", __func__,
+		nqx_dev->core_reset_ntf);
+	return nqx_dev->core_reset_ntf;
+}
+
+static long nfc_ioctl(struct file *pfile, unsigned int cmd,
+			unsigned long arg)
+{
+	int r = 0;
+
+	switch (cmd) {
+	case NFC_SET_PWR:
+		r = nfc_ioctl_power_states(pfile, cmd, arg);
+		break;
+	case SET_RX_BLOCK:
+		break;
+	case SET_EMULATOR_TEST_POINT:
+		break;
+	case NFCC_INITIAL_CORE_RESET_NTF:
+		r = nfc_ioctl_core_reset_ntf(pfile, cmd, arg);
+		break;
+	default:
+		r = -ENOIOCTLCMD;
+	}
+	return r;
+}
+
+static const struct file_operations nfc_dev_fops = {
+	.owner = THIS_MODULE,
+	.llseek = no_llseek,
+	.read  = nfc_read,
+	.write = nfc_write,
+	.open = nfc_open,
+	.unlocked_ioctl = nfc_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = nfc_compat_ioctl
+#endif
+};
+
+static int nfc_parse_dt(struct device *dev, struct nqx_platform_data *pdata)
+{
+	int r = 0;
+	struct device_node *np = dev->of_node;
+
+	pdata->dis_gpio = of_get_named_gpio(np, "qcom,dis-gpio", 0);
+	if ((!gpio_is_valid(pdata->dis_gpio)))
+		return -EINVAL;
+	disable_ctrl = pdata->dis_gpio;
+
+	pdata->irq_gpio = of_get_named_gpio(np, "qcom,irq-gpio", 0);
+	if ((!gpio_is_valid(pdata->irq_gpio)))
+		return -EINVAL;
+
+	r = of_property_read_string(np, "qcom,clk-src", &pdata->clk_src_name);
+
+	if (strcmp(pdata->clk_src_name, "GPCLK2"))
+		pdata->clkreq_gpio = of_get_named_gpio(np, "qcom,clk-gpio", 0);
+	if (r)
+		return -EINVAL;
+	return r;
+}
+
+static inline int gpio_input_init(const struct device * const dev,
+			const int gpio, const char * const gpio_name)
+{
+	int r = gpio_request(gpio, gpio_name);
+	if (r) {
+		dev_err(dev, "unable to request gpio [%d]\n", gpio);
+		return r;
+	}
+
+	r = gpio_direction_input(gpio);
+	if (r)
+		dev_err(dev, "unable to set direction for gpio [%d]\n", gpio);
+
+	return r;
+}
+
+static int nqx_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	int r = 0;
+	int irqn = 0;
+	struct nqx_platform_data *platform_data;
+	struct nqx_dev *nqx_dev;
+
+	if (client->dev.of_node) {
+		platform_data = devm_kzalloc(&client->dev,
+			sizeof(struct nqx_platform_data), GFP_KERNEL);
+		if (!platform_data) {
+			dev_err(&client->dev,
+			"%s: Failed to allocate memory\n", __func__);
+			return -ENOMEM;
+		}
+		r = nfc_parse_dt(&client->dev, platform_data);
+		if (r)
+			return r;
+	} else {
+		platform_data = client->dev.platform_data;
+	}
+	dev_dbg(&client->dev,
+		"%s, inside nfc-nci flags = %x\n",
+		__func__, client->flags);
+	if (platform_data == NULL) {
+		dev_err(&client->dev, "%s: failed\n", __func__);
+		return -ENODEV;
+	}
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "%s: need I2C_FUNC_I2C\n", __func__);
+		return -ENODEV;
+	}
+	nqx_dev = kzalloc(sizeof(*nqx_dev), GFP_KERNEL);
+	if (nqx_dev == NULL) {
+		dev_err(&client->dev,
+		"%s: failed to allocate memory for module data\n", __func__);
+		return -ENOMEM;
+	}
+	nqx_dev->client = client;
+
+	if (gpio_is_valid(platform_data->dis_gpio)) {
+		r = gpio_request(platform_data->dis_gpio, "nfc_reset_gpio");
+		if (r) {
+			dev_err(&client->dev,
+			"%s: unable to request gpio [%d]\n",
+				__func__,
+				platform_data->dis_gpio);
+			goto err_free_dev;
+		}
+		r = gpio_direction_output(platform_data->dis_gpio, 1);
+		if (r) {
+			dev_err(&client->dev,
+				"%s: unable to set direction for gpio [%d]\n",
+					__func__,
+					platform_data->dis_gpio);
+			goto err_dis_gpio;
+		}
+	} else {
+		dev_err(&client->dev, "%s: dis gpio not provided\n", __func__);
+		goto err_free_dev;
+	}
+
+	/* Register reboot notifier here */
+	r = register_reboot_notifier(&nfcc_notifier);
+	if (r) {
+		dev_err(&client->dev,
+			"%s: cannot register reboot notifier(err = %d)\n",
+			__func__, r);
+		goto err_dis_gpio;
+	}
+
+	/* Guarantee that the NFCC starts in a clean state. */
+	gpio_set_value(platform_data->dis_gpio, 1);/* HPD */
+	usleep_range(200, 220);
+	gpio_set_value(platform_data->dis_gpio, 0);/* ULPM */
+	usleep_range(200, 220);
+
+	if (gpio_is_valid(platform_data->irq_gpio)) {
+		r = gpio_request(platform_data->irq_gpio, "nfc_irq_gpio");
+		if (r) {
+			dev_err(&client->dev, "%s: unable to request gpio [%d]\n",
+				__func__,
+				platform_data->irq_gpio);
+			goto err_dis_gpio;
+		}
+		r = gpio_direction_input(platform_data->irq_gpio);
+		if (r) {
+
+			dev_err(&client->dev,
+			"%s: unable to set direction for gpio [%d]\n",
+				__func__,
+				platform_data->irq_gpio);
+			goto err_irq;
+		}
+		irqn = gpio_to_irq(platform_data->irq_gpio);
+		if (irqn < 0) {
+			r = irqn;
+			goto err_irq;
+		}
+		client->irq = irqn;
+	} else {
+		dev_err(&client->dev, "%s: irq gpio not provided\n", __func__);
+		goto err_dis_gpio;
+	}
+	if (gpio_is_valid(platform_data->clkreq_gpio)) {
+		r = gpio_request(platform_data->clkreq_gpio,
+			"nfc_clkreq_gpio");
+		if (r) {
+			dev_err(&client->dev,
+				"%s: unable to request gpio [%d]\n",
+				__func__, platform_data->clkreq_gpio);
+			goto err_clkreq_gpio;
+		}
+		r = gpio_direction_input(platform_data->clkreq_gpio);
+		if (r) {
+			dev_err(&client->dev,
+			"%s: cannot set direction for gpio [%d]\n",
+			__func__, platform_data->clkreq_gpio);
+			goto err_clkreq_gpio;
+		}
+	} else {
+		dev_err(&client->dev,
+			"%s: clkreq gpio not provided\n", __func__);
+		goto err_irq;
+	}
+	nqx_dev->clkreq_gpio = platform_data->clkreq_gpio;
+
+	nqx_dev->dis_gpio = platform_data->dis_gpio;
+	nqx_dev->irq_gpio = platform_data->irq_gpio;
+
+	/* init mutex and queues */
+	init_waitqueue_head(&nqx_dev->read_wq);
+	mutex_init(&nqx_dev->read_mutex);
+	spin_lock_init(&nqx_dev->irq_enabled_lock);
+
+	nqx_dev->nqx_device.minor = MISC_DYNAMIC_MINOR;
+	nqx_dev->nqx_device.name = "nq-nci";
+	nqx_dev->nqx_device.fops = &nfc_dev_fops;
+
+	r = misc_register(&nqx_dev->nqx_device);
+	if (r) {
+		dev_err(&client->dev, "%s: misc_register failed\n", __func__);
+		goto err_misc_register;
+	}
+
+
+	/*
+	 * Reboot the NFCC now that all resources are ready
+	 *
+	 * The NFCC takes time to transition between power states.
+	 * We wait 20uS for the NFCC to shutdown. (HPD)
+	 * We wait 100uS for the NFCC to boot into ULPM.
+	 */
+	gpio_set_value(platform_data->dis_gpio, 1);/* HPD */
+	msleep(20);
+	gpio_set_value(platform_data->dis_gpio, 0);/* ULPM */
+	msleep(100);
+
+	/* NFC_INT IRQ */
+	nqx_dev->irq_enabled = true;
+	r = request_irq(client->irq, nqx_dev_irq_handler,
+			  IRQF_TRIGGER_RISING, client->name, nqx_dev);
+	if (r) {
+		dev_err(&client->dev, "%s: request_irq failed\n", __func__);
+		goto err_request_irq_failed;
+	}
+	nqx_disable_irq(nqx_dev);
+
+	device_init_wakeup(&client->dev, true);
+	device_set_wakeup_capable(&client->dev, true);
+	i2c_set_clientdata(client, nqx_dev);
+	gpio_set_value(platform_data->dis_gpio, 1);
+
+	dev_dbg(&client->dev,
+	"%s: probing nq0 exited successfully\n",
+		 __func__);
+	return 0;
+
+err_request_irq_failed:
+	misc_deregister(&nqx_dev->nqx_device);
+err_misc_register:
+	mutex_destroy(&nqx_dev->read_mutex);
+err_clkreq_gpio:
+	if (strcmp(platform_data->clk_src_name, "GPCLK2"))
+		gpio_free(platform_data->clkreq_gpio);
+err_irq:
+	gpio_free(platform_data->irq_gpio);
+err_dis_gpio:
+	gpio_free(platform_data->dis_gpio);
+err_free_dev:
+	kfree(nqx_dev);
+
+	return r;
+}
+
+static int nqx_remove(struct i2c_client *client)
+{
+	struct nqx_dev *nqx_dev;
+
+	nqx_dev = i2c_get_clientdata(client);
+	free_irq(client->irq, nqx_dev);
+	misc_deregister(&nqx_dev->nqx_device);
+	mutex_destroy(&nqx_dev->read_mutex);
+	gpio_free(nqx_dev->irq_gpio);
+	gpio_free(nqx_dev->dis_gpio);
+
+	kfree(nqx_dev);
+	return 0;
+}
+
+static int nqx_suspend(struct device *device)
+{
+	struct i2c_client *client = to_i2c_client(device);
+
+	if (device_may_wakeup(&client->dev))
+		enable_irq_wake(client->irq);
+	return 0;
+}
+
+static int nqx_resume(struct device *device)
+{
+	struct i2c_client *client = to_i2c_client(device);
+
+	if (device_may_wakeup(&client->dev))
+		disable_irq_wake(client->irq);
+	return 0;
+}
+
+static const struct i2c_device_id nqx_id[] = {
+	{"nqx-i2c", 0},
+	{}
+};
+
+static const struct dev_pm_ops nfc_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(nqx_suspend, nqx_resume)
+};
+
+static struct i2c_driver nqx = {
+	.id_table = nqx_id,
+	.probe = nqx_probe,
+	.remove = nqx_remove,
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "nq-nci",
+		.of_match_table = msm_match_table,
+		.pm = &nfc_pm_ops,
+	},
+};
+
+
+static int nfcc_reboot(struct notifier_block *notifier, unsigned long val,
+			  void *v)
+{
+	gpio_set_value(disable_ctrl, 1);
+	return NOTIFY_OK;
+}
+
+/*
+ * module load/unload record keeping
+ */
+static int __init nqx_dev_init(void)
+{
+	return i2c_add_driver(&nqx);
+}
+module_init(nqx_dev_init);
+
+static void __exit nqx_dev_exit(void)
+{
+	unregister_reboot_notifier(&nfcc_notifier);
+	i2c_del_driver(&nqx);
+}
+module_exit(nqx_dev_exit);
+
+MODULE_DESCRIPTION("NFC nqx");
+MODULE_LICENSE("GPL v2");
+

drivers/nfc/nq-nci.h

@@ -0,0 +1,44 @@
+/* Copyright (c) 2015, 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.
+ */
+
+#ifndef __NFC_NCI_H
+#define __NFC_NCI_H
+
+#include <linux/i2c.h>
+#include <linux/types.h>
+#include <linux/version.h>
+
+#include <linux/semaphore.h>
+#include <linux/completion.h>
+
+#include <linux/ioctl.h>
+#include <linux/miscdevice.h>
+
+#define NFC_SET_PWR	_IOW(0xE9, 0x01, unsigned int)
+#define SET_RX_BLOCK	_IOW(0xE9, 0x04, unsigned int)
+#define SET_EMULATOR_TEST_POINT		_IOW(0xE9, 0x05, unsigned int)
+#define NFCC_INITIAL_CORE_RESET_NTF	_IOW(0xE9, 0x10, unsigned int)
+
+#define NFC_RX_BUFFER_CNT_START		(0x0)
+
+#define PAYLOAD_HEADER_LENGTH		(0x3)
+#define PAYLOAD_LENGTH_MAX		(256)
+#define BYTE				(0x8)
+#define NCI_IDENTIFIER			(0x10)
+
+enum nfcc_initial_core_reset_ntf {
+	TIMEDOUT_INITIAL_CORE_RESET_NTF = 0, /* 0*/
+	ARRIVED_INITIAL_CORE_RESET_NTF, /* 1 */
+	DEFAULT_INITIAL_CORE_RESET_NTF, /*2*/
+};
+
+#endif