[mirror_ubuntu-bionic-kernel.git] / drivers / nfc / st21nfcb / i2c.c

/*
 * I2C Link Layer for ST21NFCB NCI based Driver
 * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/nfc.h>
#include <linux/platform_data/st21nfcb.h>

#include "ndlc.h"

#define DRIVER_DESC "NCI NFC driver for ST21NFCB"

/* ndlc header */
#define ST21NFCB_FRAME_HEADROOM	1
#define ST21NFCB_FRAME_TAILROOM 0

#define ST21NFCB_NCI_I2C_MIN_SIZE 4   /* PCB(1) + NCI Packet header(3) */
#define ST21NFCB_NCI_I2C_MAX_SIZE 250 /* req 4.2.1 */

#define ST21NFCB_NCI_I2C_DRIVER_NAME "st21nfcb_nci_i2c"

static struct i2c_device_id st21nfcb_nci_i2c_id_table[] = {
	{ST21NFCB_NCI_DRIVER_NAME, 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, st21nfcb_nci_i2c_id_table);

struct st21nfcb_i2c_phy {
	struct i2c_client *i2c_dev;
	struct llt_ndlc *ndlc;

	unsigned int gpio_reset;
	unsigned int irq_polarity;

	int powered;
};

#define I2C_DUMP_SKB(info, skb)					\
do {								\
	pr_debug("%s:\n", info);				\
	print_hex_dump(KERN_DEBUG, "i2c: ", DUMP_PREFIX_OFFSET,	\
		       16, 1, (skb)->data, (skb)->len, 0);	\
} while (0)

static int st21nfcb_nci_i2c_enable(void *phy_id)
{
	struct st21nfcb_i2c_phy *phy = phy_id;

	gpio_set_value(phy->gpio_reset, 0);
	usleep_range(10000, 15000);
	gpio_set_value(phy->gpio_reset, 1);
	phy->powered = 1;
	usleep_range(80000, 85000);

	return 0;
}

static void st21nfcb_nci_i2c_disable(void *phy_id)
{
	struct st21nfcb_i2c_phy *phy = phy_id;

	phy->powered = 0;
	/* reset chip in order to flush clf */
	gpio_set_value(phy->gpio_reset, 0);
	usleep_range(10000, 15000);
	gpio_set_value(phy->gpio_reset, 1);
}

static void st21nfcb_nci_remove_header(struct sk_buff *skb)
{
	skb_pull(skb, ST21NFCB_FRAME_HEADROOM);
}

/*
 * Writing a frame must not return the number of written bytes.
 * It must return either zero for success, or <0 for error.
 * In addition, it must not alter the skb
 */
static int st21nfcb_nci_i2c_write(void *phy_id, struct sk_buff *skb)
{
	int r = -1;
	struct st21nfcb_i2c_phy *phy = phy_id;
	struct i2c_client *client = phy->i2c_dev;

	I2C_DUMP_SKB("st21nfcb_nci_i2c_write", skb);

	if (phy->ndlc->hard_fault != 0)
		return phy->ndlc->hard_fault;

	r = i2c_master_send(client, skb->data, skb->len);
	if (r == -EREMOTEIO) {  /* Retry, chip was in standby */
		usleep_range(1000, 4000);
		r = i2c_master_send(client, skb->data, skb->len);
	}

	if (r >= 0) {
		if (r != skb->len)
			r = -EREMOTEIO;
		else
			r = 0;
	}

	st21nfcb_nci_remove_header(skb);

	return r;
}

/*
 * Reads an ndlc frame and returns it in a newly allocated sk_buff.
 * returns:
 * frame size : if received frame is complete (find ST21NFCB_SOF_EOF at
 * end of read)
 * -EAGAIN : if received frame is incomplete (not find ST21NFCB_SOF_EOF
 * at end of read)
 * -EREMOTEIO : i2c read error (fatal)
 * -EBADMSG : frame was incorrect and discarded
 * (value returned from st21nfcb_nci_i2c_repack)
 * -EIO : if no ST21NFCB_SOF_EOF is found after reaching
 * the read length end sequence
 */
static int st21nfcb_nci_i2c_read(struct st21nfcb_i2c_phy *phy,
				 struct sk_buff **skb)
{
	int r;
	u8 len;
	u8 buf[ST21NFCB_NCI_I2C_MAX_SIZE];
	struct i2c_client *client = phy->i2c_dev;

	r = i2c_master_recv(client, buf, ST21NFCB_NCI_I2C_MIN_SIZE);
	if (r == -EREMOTEIO) {  /* Retry, chip was in standby */
		usleep_range(1000, 4000);
		r = i2c_master_recv(client, buf, ST21NFCB_NCI_I2C_MIN_SIZE);
	}

	if (r != ST21NFCB_NCI_I2C_MIN_SIZE)
		return -EREMOTEIO;

	len = be16_to_cpu(*(__be16 *) (buf + 2));
	if (len > ST21NFCB_NCI_I2C_MAX_SIZE) {
		nfc_err(&client->dev, "invalid frame len\n");
		return -EBADMSG;
	}

	*skb = alloc_skb(ST21NFCB_NCI_I2C_MIN_SIZE + len, GFP_KERNEL);
	if (*skb == NULL)
		return -ENOMEM;

	skb_reserve(*skb, ST21NFCB_NCI_I2C_MIN_SIZE);
	skb_put(*skb, ST21NFCB_NCI_I2C_MIN_SIZE);
	memcpy((*skb)->data, buf, ST21NFCB_NCI_I2C_MIN_SIZE);

	if (!len)
		return 0;

	r = i2c_master_recv(client, buf, len);
	if (r != len) {
		kfree_skb(*skb);
		return -EREMOTEIO;
	}

	skb_put(*skb, len);
	memcpy((*skb)->data + ST21NFCB_NCI_I2C_MIN_SIZE, buf, len);

	I2C_DUMP_SKB("i2c frame read", *skb);

	return 0;
}

/*
 * Reads an ndlc frame from the chip.
 *
 * On ST21NFCB, IRQ goes in idle state when read starts.
 */
static irqreturn_t st21nfcb_nci_irq_thread_fn(int irq, void *phy_id)
{
	struct st21nfcb_i2c_phy *phy = phy_id;
	struct i2c_client *client;
	struct sk_buff *skb = NULL;
	int r;

	if (!phy || irq != phy->i2c_dev->irq) {
		WARN_ON_ONCE(1);
		return IRQ_NONE;
	}

	client = phy->i2c_dev;
	dev_dbg(&client->dev, "IRQ\n");

	if (phy->ndlc->hard_fault)
		return IRQ_HANDLED;

	if (!phy->powered) {
		st21nfcb_nci_i2c_disable(phy);
		return IRQ_HANDLED;
	}

	r = st21nfcb_nci_i2c_read(phy, &skb);
	if (r == -EREMOTEIO || r == -ENOMEM || r == -EBADMSG)
		return IRQ_HANDLED;

	ndlc_recv(phy->ndlc, skb);

	return IRQ_HANDLED;
}

static struct nfc_phy_ops i2c_phy_ops = {
	.write = st21nfcb_nci_i2c_write,
	.enable = st21nfcb_nci_i2c_enable,
	.disable = st21nfcb_nci_i2c_disable,
};

#ifdef CONFIG_OF
static int st21nfcb_nci_i2c_of_request_resources(struct i2c_client *client)
{
	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);
	struct device_node *pp;
	int gpio;
	int r;

	pp = client->dev.of_node;
	if (!pp)
		return -ENODEV;

	/* Get GPIO from device tree */
	gpio = of_get_named_gpio(pp, "reset-gpios", 0);
	if (gpio < 0) {
		nfc_err(&client->dev,
			"Failed to retrieve reset-gpios from device tree\n");
		return gpio;
	}

	/* GPIO request and configuration */
	r = devm_gpio_request_one(&client->dev, gpio,
				GPIOF_OUT_INIT_HIGH, "clf_reset");
	if (r) {
		nfc_err(&client->dev, "Failed to request reset pin\n");
		return r;
	}
	phy->gpio_reset = gpio;

	phy->irq_polarity = irq_get_trigger_type(client->irq);

	return 0;
}
#else
static int st21nfcb_nci_i2c_of_request_resources(struct i2c_client *client)
{
	return -ENODEV;
}
#endif

static int st21nfcb_nci_i2c_request_resources(struct i2c_client *client)
{
	struct st21nfcb_nfc_platform_data *pdata;
	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);
	int r;

	pdata = client->dev.platform_data;
	if (pdata == NULL) {
		nfc_err(&client->dev, "No platform data\n");
		return -EINVAL;
	}

	/* store for later use */
	phy->gpio_reset = pdata->gpio_reset;
	phy->irq_polarity = pdata->irq_polarity;

	r = devm_gpio_request_one(&client->dev,
			phy->gpio_reset, GPIOF_OUT_INIT_HIGH, "clf_reset");
	if (r) {
		pr_err("%s : reset gpio_request failed\n", __FILE__);
		return r;
	}

	return 0;
}

static int st21nfcb_nci_i2c_probe(struct i2c_client *client,
				  const struct i2c_device_id *id)
{
	struct st21nfcb_i2c_phy *phy;
	struct st21nfcb_nfc_platform_data *pdata;
	int r;

	dev_dbg(&client->dev, "%s\n", __func__);
	dev_dbg(&client->dev, "IRQ: %d\n", client->irq);

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
		nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
		return -ENODEV;
	}

	phy = devm_kzalloc(&client->dev, sizeof(struct st21nfcb_i2c_phy),
			   GFP_KERNEL);
	if (!phy) {
		nfc_err(&client->dev,
			"Cannot allocate memory for st21nfcb i2c phy.\n");
		return -ENOMEM;
	}

	phy->i2c_dev = client;

	i2c_set_clientdata(client, phy);

	pdata = client->dev.platform_data;
	if (!pdata && client->dev.of_node) {
		r = st21nfcb_nci_i2c_of_request_resources(client);
		if (r) {
			nfc_err(&client->dev, "No platform data\n");
			return r;
		}
	} else if (pdata) {
		r = st21nfcb_nci_i2c_request_resources(client);
		if (r) {
			nfc_err(&client->dev,
				"Cannot get platform resources\n");
			return r;
		}
	} else {
		nfc_err(&client->dev,
			"st21nfcb platform resources not available\n");
		return -ENODEV;
	}

	r = devm_request_threaded_irq(&client->dev, client->irq, NULL,
				st21nfcb_nci_irq_thread_fn,
				phy->irq_polarity | IRQF_ONESHOT,
				ST21NFCB_NCI_DRIVER_NAME, phy);
	if (r < 0) {
		nfc_err(&client->dev, "Unable to register IRQ handler\n");
		return r;
	}

	return ndlc_probe(phy, &i2c_phy_ops, &client->dev,
			ST21NFCB_FRAME_HEADROOM, ST21NFCB_FRAME_TAILROOM,
			&phy->ndlc);
}

static int st21nfcb_nci_i2c_remove(struct i2c_client *client)
{
	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);

	dev_dbg(&client->dev, "%s\n", __func__);

	ndlc_remove(phy->ndlc);

	if (phy->powered)
		st21nfcb_nci_i2c_disable(phy);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id of_st21nfcb_i2c_match[] = {
	{ .compatible = "st,st21nfcb_i2c", },
	{}
};
MODULE_DEVICE_TABLE(of, of_st21nfcb_i2c_match);
#endif

static struct i2c_driver st21nfcb_nci_i2c_driver = {
	.driver = {
		.owner = THIS_MODULE,
		.name = ST21NFCB_NCI_I2C_DRIVER_NAME,
		.of_match_table = of_match_ptr(of_st21nfcb_i2c_match),
	},
	.probe = st21nfcb_nci_i2c_probe,
	.id_table = st21nfcb_nci_i2c_id_table,
	.remove = st21nfcb_nci_i2c_remove,
};

module_i2c_driver(st21nfcb_nci_i2c_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION(DRIVER_DESC);
Commit	Line	Data
35630df6 CR	1	/*
	2	* I2C Link Layer for ST21NFCB NCI based Driver
	3	* Copyright (C) 2014 STMicroelectronics SAS. All rights reserved.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms and conditions of the GNU General Public License,
	7	* version 2, as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	16	*/
	17
	18	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	19
35630df6 CR	20	#include <linux/module.h>
	21	#include <linux/i2c.h>
	22	#include <linux/gpio.h>
	23	#include <linux/of_irq.h>
	24	#include <linux/of_gpio.h>
35630df6 CR	25	#include <linux/interrupt.h>
	26	#include <linux/delay.h>
	27	#include <linux/nfc.h>
35630df6 CR	28	#include <linux/platform_data/st21nfcb.h>
35630df6 CR	29
35630df6 CR	30	#include "ndlc.h"
	31
	32	#define DRIVER_DESC "NCI NFC driver for ST21NFCB"
	33
	34	/* ndlc header */
	35	#define ST21NFCB_FRAME_HEADROOM 1
	36	#define ST21NFCB_FRAME_TAILROOM 0
	37
	38	#define ST21NFCB_NCI_I2C_MIN_SIZE 4 /* PCB(1) + NCI Packet header(3) */
	39	#define ST21NFCB_NCI_I2C_MAX_SIZE 250 /* req 4.2.1 */
	40
	41	#define ST21NFCB_NCI_I2C_DRIVER_NAME "st21nfcb_nci_i2c"
	42
	43	static struct i2c_device_id st21nfcb_nci_i2c_id_table[] = {
	44	{ST21NFCB_NCI_DRIVER_NAME, 0},
	45	{}
	46	};
	47	MODULE_DEVICE_TABLE(i2c, st21nfcb_nci_i2c_id_table);
	48
	49	struct st21nfcb_i2c_phy {
	50	struct i2c_client *i2c_dev;
	51	struct llt_ndlc *ndlc;
	52
35630df6 CR	53	unsigned int gpio_reset;
	54	unsigned int irq_polarity;
	55
	56	int powered;
35630df6 CR	57	};
	58
	59	#define I2C_DUMP_SKB(info, skb) \
	60	do { \
	61	pr_debug("%s:\n", info); \
	62	print_hex_dump(KERN_DEBUG, "i2c: ", DUMP_PREFIX_OFFSET, \
	63	16, 1, (skb)->data, (skb)->len, 0); \
	64	} while (0)
	65
	66	static int st21nfcb_nci_i2c_enable(void *phy_id)
	67	{
	68	struct st21nfcb_i2c_phy *phy = phy_id;
	69
	70	gpio_set_value(phy->gpio_reset, 0);
	71	usleep_range(10000, 15000);
	72	gpio_set_value(phy->gpio_reset, 1);
	73	phy->powered = 1;
	74	usleep_range(80000, 85000);
	75
	76	return 0;
	77	}
	78
	79	static void st21nfcb_nci_i2c_disable(void *phy_id)
	80	{
	81	struct st21nfcb_i2c_phy *phy = phy_id;
	82
35630df6 CR	83	phy->powered = 0;
	84	/* reset chip in order to flush clf */
	85	gpio_set_value(phy->gpio_reset, 0);
	86	usleep_range(10000, 15000);
	87	gpio_set_value(phy->gpio_reset, 1);
	88	}
	89
	90	static void st21nfcb_nci_remove_header(struct sk_buff *skb)
	91	{
	92	skb_pull(skb, ST21NFCB_FRAME_HEADROOM);
	93	}
	94
	95	/*
	96	* Writing a frame must not return the number of written bytes.
	97	* It must return either zero for success, or <0 for error.
	98	* In addition, it must not alter the skb
	99	*/
	100	static int st21nfcb_nci_i2c_write(void phy_id, struct sk_buff skb)
	101	{
	102	int r = -1;
	103	struct st21nfcb_i2c_phy *phy = phy_id;
	104	struct i2c_client *client = phy->i2c_dev;
	105
	106	I2C_DUMP_SKB("st21nfcb_nci_i2c_write", skb);
	107
4294e320 CR	108	if (phy->ndlc->hard_fault != 0)
4294e320 CR	109	return phy->ndlc->hard_fault;
35630df6 CR	110
	111	r = i2c_master_send(client, skb->data, skb->len);
	112	if (r == -EREMOTEIO) { /* Retry, chip was in standby */
	113	usleep_range(1000, 4000);
	114	r = i2c_master_send(client, skb->data, skb->len);
	115	}
	116
	117	if (r >= 0) {
	118	if (r != skb->len)
	119	r = -EREMOTEIO;
	120	else
	121	r = 0;
	122	}
	123
	124	st21nfcb_nci_remove_header(skb);
	125
	126	return r;
	127	}
	128
	129	/*
	130	* Reads an ndlc frame and returns it in a newly allocated sk_buff.
	131	* returns:
	132	* frame size : if received frame is complete (find ST21NFCB_SOF_EOF at
	133	* end of read)
	134	* -EAGAIN : if received frame is incomplete (not find ST21NFCB_SOF_EOF
	135	* at end of read)
	136	* -EREMOTEIO : i2c read error (fatal)
	137	* -EBADMSG : frame was incorrect and discarded
	138	* (value returned from st21nfcb_nci_i2c_repack)
	139	* -EIO : if no ST21NFCB_SOF_EOF is found after reaching
	140	* the read length end sequence
	141	*/
	142	static int st21nfcb_nci_i2c_read(struct st21nfcb_i2c_phy *phy,
	143	struct sk_buff **skb)
	144	{
	145	int r;
	146	u8 len;
	147	u8 buf[ST21NFCB_NCI_I2C_MAX_SIZE];
	148	struct i2c_client *client = phy->i2c_dev;
	149
fb92ff78	150	r = i2c_master_recv(client, buf, ST21NFCB_NCI_I2C_MIN_SIZE);
35630df6 CR	151	if (r == -EREMOTEIO) { /* Retry, chip was in standby */
35630df6 CR	152	usleep_range(1000, 4000);
fb92ff78	153	r = i2c_master_recv(client, buf, ST21NFCB_NCI_I2C_MIN_SIZE);
ac633ba6 CR	154	}
ac633ba6 CR	155
bc6b8275	156	if (r != ST21NFCB_NCI_I2C_MIN_SIZE)
35630df6	157	return -EREMOTEIO;
35630df6 CR	158
	159	len = be16_to_cpu((__be16 ) (buf + 2));
	160	if (len > ST21NFCB_NCI_I2C_MAX_SIZE) {
	161	nfc_err(&client->dev, "invalid frame len\n");
	162	return -EBADMSG;
	163	}
	164
fb92ff78	165	*skb = alloc_skb(ST21NFCB_NCI_I2C_MIN_SIZE + len, GFP_KERNEL);
35630df6 CR	166	if (*skb == NULL)
	167	return -ENOMEM;
	168
fb92ff78 CR	169	skb_reserve(*skb, ST21NFCB_NCI_I2C_MIN_SIZE);
	170	skb_put(*skb, ST21NFCB_NCI_I2C_MIN_SIZE);
	171	memcpy((*skb)->data, buf, ST21NFCB_NCI_I2C_MIN_SIZE);
35630df6 CR	172
	173	if (!len)
	174	return 0;
	175
	176	r = i2c_master_recv(client, buf, len);
	177	if (r != len) {
	178	kfree_skb(*skb);
	179	return -EREMOTEIO;
	180	}
	181
	182	skb_put(*skb, len);
fb92ff78	183	memcpy((*skb)->data + ST21NFCB_NCI_I2C_MIN_SIZE, buf, len);
35630df6 CR	184
	185	I2C_DUMP_SKB("i2c frame read", *skb);
	186
	187	return 0;
	188	}
	189
	190	/*
	191	* Reads an ndlc frame from the chip.
	192	*
	193	* On ST21NFCB, IRQ goes in idle state when read starts.
	194	*/
	195	static irqreturn_t st21nfcb_nci_irq_thread_fn(int irq, void *phy_id)
	196	{
	197	struct st21nfcb_i2c_phy *phy = phy_id;
	198	struct i2c_client *client;
	199	struct sk_buff *skb = NULL;
	200	int r;
	201
	202	if (!phy \|\| irq != phy->i2c_dev->irq) {
	203	WARN_ON_ONCE(1);
	204	return IRQ_NONE;
	205	}
	206
	207	client = phy->i2c_dev;
	208	dev_dbg(&client->dev, "IRQ\n");
	209
4294e320	210	if (phy->ndlc->hard_fault)
35630df6 CR	211	return IRQ_HANDLED;
	212
	213	if (!phy->powered) {
	214	st21nfcb_nci_i2c_disable(phy);
	215	return IRQ_HANDLED;
	216	}
	217
	218	r = st21nfcb_nci_i2c_read(phy, &skb);
4294e320	219	if (r == -EREMOTEIO \|\| r == -ENOMEM \|\| r == -EBADMSG)
35630df6	220	return IRQ_HANDLED;
35630df6 CR	221
	222	ndlc_recv(phy->ndlc, skb);
	223
	224	return IRQ_HANDLED;
	225	}
	226
	227	static struct nfc_phy_ops i2c_phy_ops = {
	228	.write = st21nfcb_nci_i2c_write,
	229	.enable = st21nfcb_nci_i2c_enable,
	230	.disable = st21nfcb_nci_i2c_disable,
	231	};
	232
	233	#ifdef CONFIG_OF
	234	static int st21nfcb_nci_i2c_of_request_resources(struct i2c_client *client)
	235	{
	236	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);
	237	struct device_node *pp;
	238	int gpio;
	239	int r;
	240
	241	pp = client->dev.of_node;
	242	if (!pp)
	243	return -ENODEV;
	244
	245	/* Get GPIO from device tree */
	246	gpio = of_get_named_gpio(pp, "reset-gpios", 0);
	247	if (gpio < 0) {
	248	nfc_err(&client->dev,
	249	"Failed to retrieve reset-gpios from device tree\n");
	250	return gpio;
	251	}
	252
	253	/* GPIO request and configuration */
56ee645e CR	254	r = devm_gpio_request_one(&client->dev, gpio,
56ee645e CR	255	GPIOF_OUT_INIT_HIGH, "clf_reset");
35630df6 CR	256	if (r) {
35630df6 CR	257	nfc_err(&client->dev, "Failed to request reset pin\n");
18159624	258	return r;
35630df6	259	}
35630df6 CR	260	phy->gpio_reset = gpio;
35630df6 CR	261
a80d0cb6	262	phy->irq_polarity = irq_get_trigger_type(client->irq);
35630df6 CR	263
	264	return 0;
	265	}
	266	#else
	267	static int st21nfcb_nci_i2c_of_request_resources(struct i2c_client *client)
	268	{
	269	return -ENODEV;
	270	}
	271	#endif
	272
	273	static int st21nfcb_nci_i2c_request_resources(struct i2c_client *client)
	274	{
	275	struct st21nfcb_nfc_platform_data *pdata;
	276	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);
	277	int r;
35630df6 CR	278
	279	pdata = client->dev.platform_data;
	280	if (pdata == NULL) {
	281	nfc_err(&client->dev, "No platform data\n");
	282	return -EINVAL;
	283	}
	284
	285	/* store for later use */
35630df6 CR	286	phy->gpio_reset = pdata->gpio_reset;
	287	phy->irq_polarity = pdata->irq_polarity;
	288
56ee645e CR	289	r = devm_gpio_request_one(&client->dev,
56ee645e CR	290	phy->gpio_reset, GPIOF_OUT_INIT_HIGH, "clf_reset");
35630df6 CR	291	if (r) {
35630df6 CR	292	pr_err("%s : reset gpio_request failed\n", __FILE__);
18159624	293	return r;
35630df6 CR	294	}
35630df6 CR	295
35630df6 CR	296	return 0;
	297	}
	298
	299	static int st21nfcb_nci_i2c_probe(struct i2c_client *client,
	300	const struct i2c_device_id *id)
	301	{
	302	struct st21nfcb_i2c_phy *phy;
	303	struct st21nfcb_nfc_platform_data *pdata;
	304	int r;
	305
	306	dev_dbg(&client->dev, "%s\n", __func__);
	307	dev_dbg(&client->dev, "IRQ: %d\n", client->irq);
	308
	309	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
	310	nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
	311	return -ENODEV;
	312	}
	313
	314	phy = devm_kzalloc(&client->dev, sizeof(struct st21nfcb_i2c_phy),
	315	GFP_KERNEL);
	316	if (!phy) {
	317	nfc_err(&client->dev,
	318	"Cannot allocate memory for st21nfcb i2c phy.\n");
	319	return -ENOMEM;
	320	}
	321
	322	phy->i2c_dev = client;
	323
	324	i2c_set_clientdata(client, phy);
	325
	326	pdata = client->dev.platform_data;
	327	if (!pdata && client->dev.of_node) {
	328	r = st21nfcb_nci_i2c_of_request_resources(client);
	329	if (r) {
	330	nfc_err(&client->dev, "No platform data\n");
	331	return r;
	332	}
	333	} else if (pdata) {
	334	r = st21nfcb_nci_i2c_request_resources(client);
	335	if (r) {
	336	nfc_err(&client->dev,
	337	"Cannot get platform resources\n");
	338	return r;
	339	}
	340	} else {
	341	nfc_err(&client->dev,
	342	"st21nfcb platform resources not available\n");
	343	return -ENODEV;
	344	}
	345
	346	r = devm_request_threaded_irq(&client->dev, client->irq, NULL,
	347	st21nfcb_nci_irq_thread_fn,
	348	phy->irq_polarity \| IRQF_ONESHOT,
	349	ST21NFCB_NCI_DRIVER_NAME, phy);
	350	if (r < 0) {
	351	nfc_err(&client->dev, "Unable to register IRQ handler\n");
	352	return r;
	353	}
	354
	355	return ndlc_probe(phy, &i2c_phy_ops, &client->dev,
	356	ST21NFCB_FRAME_HEADROOM, ST21NFCB_FRAME_TAILROOM,
	357	&phy->ndlc);
	358	}
	359
360	static int st21nfcb_nci_i2c_remove(struct i2c_client *client)
361	{
362	struct st21nfcb_i2c_phy *phy = i2c_get_clientdata(client);
363
364	dev_dbg(&client->dev, "%s\n", __func__);
365
366	ndlc_remove(phy->ndlc);
367
368	if (phy->powered)
369	st21nfcb_nci_i2c_disable(phy);
370
371	return 0;
372	}
373
d9b66918	374	#ifdef CONFIG_OF
35630df6 CR	375	static const struct of_device_id of_st21nfcb_i2c_match[] = {
	376	{ .compatible = "st,st21nfcb_i2c", },
	377	{}
	378	};
d9b66918 CR	379	MODULE_DEVICE_TABLE(of, of_st21nfcb_i2c_match);
d9b66918 CR	380	#endif
35630df6 CR	381
	382	static struct i2c_driver st21nfcb_nci_i2c_driver = {
	383	.driver = {
	384	.owner = THIS_MODULE,
	385	.name = ST21NFCB_NCI_I2C_DRIVER_NAME,
35630df6 CR	386	.of_match_table = of_match_ptr(of_st21nfcb_i2c_match),
	387	},
	388	.probe = st21nfcb_nci_i2c_probe,
	389	.id_table = st21nfcb_nci_i2c_id_table,
	390	.remove = st21nfcb_nci_i2c_remove,
	391	};
	392
	393	module_i2c_driver(st21nfcb_nci_i2c_driver);
	394
	395	MODULE_LICENSE("GPL");
	396	MODULE_DESCRIPTION(DRIVER_DESC);