[mirror_ubuntu-jammy-kernel.git] / drivers / nfc / st-nci / spi.c

/*
 * SPI Link Layer for ST NCI based Driver
 * Copyright (C) 2014-2015 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/spi/spi.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 <net/nfc/nci.h>
#include <linux/platform_data/st-nci.h>

#include "st-nci.h"

#define DRIVER_DESC "NCI NFC driver for ST_NCI"

/* ndlc header */
#define ST_NCI_FRAME_HEADROOM	1
#define ST_NCI_FRAME_TAILROOM 0

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

#define ST_NCI_SPI_DRIVER_NAME "st_nci_spi"

static struct spi_device_id st_nci_spi_id_table[] = {
	{ST_NCI_SPI_DRIVER_NAME, 0},
	{}
};
MODULE_DEVICE_TABLE(spi, st_nci_spi_id_table);

struct st_nci_spi_phy {
	struct spi_device *spi_dev;
	struct llt_ndlc *ndlc;

	unsigned int gpio_reset;
	unsigned int irq_polarity;
};

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

static int st_nci_spi_enable(void *phy_id)
{
	struct st_nci_spi_phy *phy = phy_id;

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

	if (phy->ndlc->powered == 0)
		enable_irq(phy->spi_dev->irq);

	return 0;
}

static void st_nci_spi_disable(void *phy_id)
{
	struct st_nci_spi_phy *phy = phy_id;

	disable_irq_nosync(phy->spi_dev->irq);
}

/*
 * 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 st_nci_spi_write(void *phy_id, struct sk_buff *skb)
{
	int r;
	struct st_nci_spi_phy *phy = phy_id;
	struct spi_device *dev = phy->spi_dev;
	struct sk_buff *skb_rx;
	u8 buf[ST_NCI_SPI_MAX_SIZE + NCI_DATA_HDR_SIZE +
	       ST_NCI_FRAME_HEADROOM + ST_NCI_FRAME_TAILROOM];
	struct spi_transfer spi_xfer = {
		.tx_buf = skb->data,
		.rx_buf = buf,
		.len = skb->len,
	};

	SPI_DUMP_SKB("st_nci_spi_write", skb);

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

	r = spi_sync_transfer(dev, &spi_xfer, 1);
	/*
	 * We may have received some valuable data on miso line.
	 * Send them back in the ndlc state machine.
	 */
	if (!r) {
		skb_rx = alloc_skb(skb->len, GFP_KERNEL);
		if (!skb_rx) {
			r = -ENOMEM;
			goto exit;
		}

		skb_put(skb_rx, skb->len);
		memcpy(skb_rx->data, buf, skb->len);
		ndlc_recv(phy->ndlc, skb_rx);
	}

exit:
	return r;
}

/*
 * Reads an ndlc frame and returns it in a newly allocated sk_buff.
 * returns:
 * 0 : if received frame is complete
 * -EREMOTEIO : i2c read error (fatal)
 * -EBADMSG : frame was incorrect and discarded
 * -ENOMEM : cannot allocate skb, frame dropped
 */
static int st_nci_spi_read(struct st_nci_spi_phy *phy,
			struct sk_buff **skb)
{
	int r;
	u8 len;
	u8 buf[ST_NCI_SPI_MAX_SIZE];
	struct spi_device *dev = phy->spi_dev;
	struct spi_transfer spi_xfer = {
		.rx_buf = buf,
		.len = ST_NCI_SPI_MIN_SIZE,
	};

	r = spi_sync_transfer(dev, &spi_xfer, 1);
	if (r < 0)
		return -EREMOTEIO;

	len = be16_to_cpu(*(__be16 *) (buf + 2));
	if (len > ST_NCI_SPI_MAX_SIZE) {
		nfc_err(&dev->dev, "invalid frame len\n");
		phy->ndlc->hard_fault = 1;
		return -EBADMSG;
	}

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

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

	if (!len)
		return 0;

	spi_xfer.len = len;
	r = spi_sync_transfer(dev, &spi_xfer, 1);
	if (r < 0) {
		kfree_skb(*skb);
		return -EREMOTEIO;
	}

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

	SPI_DUMP_SKB("spi 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 st_nci_irq_thread_fn(int irq, void *phy_id)
{
	struct st_nci_spi_phy *phy = phy_id;
	struct spi_device *dev;
	struct sk_buff *skb = NULL;
	int r;

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

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

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

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

	r = st_nci_spi_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 spi_phy_ops = {
	.write = st_nci_spi_write,
	.enable = st_nci_spi_enable,
	.disable = st_nci_spi_disable,
};

#ifdef CONFIG_OF
static int st_nci_spi_of_request_resources(struct spi_device *dev)
{
	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);
	struct device_node *pp;
	int gpio;
	int r;

	pp = dev->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(&dev->dev,
			"Failed to retrieve reset-gpios from device tree\n");
		return gpio;
	}

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

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

	return 0;
}
#else
static int st_nci_spi_of_request_resources(struct spi_device *dev)
{
	return -ENODEV;
}
#endif

static int st_nci_spi_request_resources(struct spi_device *dev)
{
	struct st_nci_nfc_platform_data *pdata;
	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);
	int r;

	pdata = dev->dev.platform_data;
	if (pdata == NULL) {
		nfc_err(&dev->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(&dev->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 st_nci_spi_probe(struct spi_device *dev)
{
	struct st_nci_spi_phy *phy;
	struct st_nci_nfc_platform_data *pdata;
	int r;

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

	/* Check SPI platform functionnalities */
	if (!dev) {
		pr_debug("%s: dev is NULL. Device is not accessible.\n",
			__func__);
		return -ENODEV;
	}

	phy = devm_kzalloc(&dev->dev, sizeof(struct st_nci_spi_phy),
			   GFP_KERNEL);
	if (!phy)
		return -ENOMEM;

	phy->spi_dev = dev;

	spi_set_drvdata(dev, phy);

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

	r = ndlc_probe(phy, &spi_phy_ops, &dev->dev,
			ST_NCI_FRAME_HEADROOM, ST_NCI_FRAME_TAILROOM,
			&phy->ndlc);
	if (r < 0) {
		nfc_err(&dev->dev, "Unable to register ndlc layer\n");
		return r;
	}

	r = devm_request_threaded_irq(&dev->dev, dev->irq, NULL,
				st_nci_irq_thread_fn,
				phy->irq_polarity | IRQF_ONESHOT,
				ST_NCI_SPI_DRIVER_NAME, phy);
	if (r < 0)
		nfc_err(&dev->dev, "Unable to register IRQ handler\n");

	return r;
}

static int st_nci_spi_remove(struct spi_device *dev)
{
	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);

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

	ndlc_remove(phy->ndlc);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id of_st_nci_spi_match[] = {
	{ .compatible = "st,st21nfcb-spi", },
	{}
};
MODULE_DEVICE_TABLE(of, of_st_nci_spi_match);
#endif

static struct spi_driver st_nci_spi_driver = {
	.driver = {
		.owner = THIS_MODULE,
		.name = ST_NCI_SPI_DRIVER_NAME,
		.of_match_table = of_match_ptr(of_st_nci_spi_match),
	},
	.probe = st_nci_spi_probe,
	.id_table = st_nci_spi_id_table,
	.remove = st_nci_spi_remove,
};

module_spi_driver(st_nci_spi_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION(DRIVER_DESC);
Commit	Line	Data
2bc4d4f8 CR	1	/*
	2	* SPI Link Layer for ST NCI based Driver
	3	* Copyright (C) 2014-2015 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
	20	#include <linux/module.h>
	21	#include <linux/spi/spi.h>
	22	#include <linux/gpio.h>
	23	#include <linux/of_irq.h>
	24	#include <linux/of_gpio.h>
	25	#include <linux/interrupt.h>
	26	#include <linux/delay.h>
	27	#include <linux/nfc.h>
a1269dd1	28	#include <net/nfc/nci.h>
2bc4d4f8 CR	29	#include <linux/platform_data/st-nci.h>
2bc4d4f8 CR	30
e67e7e59	31	#include "st-nci.h"
2bc4d4f8 CR	32
	33	#define DRIVER_DESC "NCI NFC driver for ST_NCI"
	34
	35	/* ndlc header */
	36	#define ST_NCI_FRAME_HEADROOM 1
	37	#define ST_NCI_FRAME_TAILROOM 0
	38
	39	#define ST_NCI_SPI_MIN_SIZE 4 /* PCB(1) + NCI Packet header(3) */
	40	#define ST_NCI_SPI_MAX_SIZE 250 /* req 4.2.1 */
	41
	42	#define ST_NCI_SPI_DRIVER_NAME "st_nci_spi"
	43
	44	static struct spi_device_id st_nci_spi_id_table[] = {
	45	{ST_NCI_SPI_DRIVER_NAME, 0},
	46	{}
	47	};
	48	MODULE_DEVICE_TABLE(spi, st_nci_spi_id_table);
	49
	50	struct st_nci_spi_phy {
	51	struct spi_device *spi_dev;
	52	struct llt_ndlc *ndlc;
	53
	54	unsigned int gpio_reset;
	55	unsigned int irq_polarity;
	56	};
	57
	58	#define SPI_DUMP_SKB(info, skb) \
	59	do { \
	60	pr_debug("%s:\n", info); \
	61	print_hex_dump(KERN_DEBUG, "spi: ", DUMP_PREFIX_OFFSET, \
	62	16, 1, (skb)->data, (skb)->len, 0); \
	63	} while (0)
	64
	65	static int st_nci_spi_enable(void *phy_id)
	66	{
	67	struct st_nci_spi_phy *phy = phy_id;
	68
	69	gpio_set_value(phy->gpio_reset, 0);
	70	usleep_range(10000, 15000);
	71	gpio_set_value(phy->gpio_reset, 1);
	72	usleep_range(80000, 85000);
	73
	74	if (phy->ndlc->powered == 0)
	75	enable_irq(phy->spi_dev->irq);
	76
	77	return 0;
	78	}
	79
	80	static void st_nci_spi_disable(void *phy_id)
	81	{
	82	struct st_nci_spi_phy *phy = phy_id;
	83
	84	disable_irq_nosync(phy->spi_dev->irq);
	85	}
	86
	87	/*
	88	* Writing a frame must not return the number of written bytes.
	89	* It must return either zero for success, or <0 for error.
	90	* In addition, it must not alter the skb
	91	*/
	92	static int st_nci_spi_write(void phy_id, struct sk_buff skb)
	93	{
	94	int r;
	95	struct st_nci_spi_phy *phy = phy_id;
96	struct spi_device *dev = phy->spi_dev;
97	struct sk_buff *skb_rx;
a1269dd1 CR	98	u8 buf[ST_NCI_SPI_MAX_SIZE + NCI_DATA_HDR_SIZE +
a1269dd1 CR	99	ST_NCI_FRAME_HEADROOM + ST_NCI_FRAME_TAILROOM];
2bc4d4f8 CR	100	struct spi_transfer spi_xfer = {
	101	.tx_buf = skb->data,
	102	.rx_buf = buf,
	103	.len = skb->len,
	104	};
	105
	106	SPI_DUMP_SKB("st_nci_spi_write", skb);
	107
	108	if (phy->ndlc->hard_fault != 0)
	109	return phy->ndlc->hard_fault;
	110
	111	r = spi_sync_transfer(dev, &spi_xfer, 1);
	112	/*
	113	* We may have received some valuable data on miso line.
	114	* Send them back in the ndlc state machine.
	115	*/
	116	if (!r) {
	117	skb_rx = alloc_skb(skb->len, GFP_KERNEL);
	118	if (!skb_rx) {
	119	r = -ENOMEM;
	120	goto exit;
	121	}
	122
	123	skb_put(skb_rx, skb->len);
	124	memcpy(skb_rx->data, buf, skb->len);
	125	ndlc_recv(phy->ndlc, skb_rx);
	126	}
	127
	128	exit:
	129	return r;
	130	}
	131
	132	/*
	133	* Reads an ndlc frame and returns it in a newly allocated sk_buff.
	134	* returns:
	135	* 0 : if received frame is complete
	136	* -EREMOTEIO : i2c read error (fatal)
	137	* -EBADMSG : frame was incorrect and discarded
	138	* -ENOMEM : cannot allocate skb, frame dropped
	139	*/
	140	static int st_nci_spi_read(struct st_nci_spi_phy *phy,
	141	struct sk_buff **skb)
	142	{
	143	int r;
	144	u8 len;
	145	u8 buf[ST_NCI_SPI_MAX_SIZE];
	146	struct spi_device *dev = phy->spi_dev;
	147	struct spi_transfer spi_xfer = {
	148	.rx_buf = buf,
	149	.len = ST_NCI_SPI_MIN_SIZE,
	150	};
	151
	152	r = spi_sync_transfer(dev, &spi_xfer, 1);
	153	if (r < 0)
	154	return -EREMOTEIO;
	155
	156	len = be16_to_cpu((__be16 ) (buf + 2));
	157	if (len > ST_NCI_SPI_MAX_SIZE) {
	158	nfc_err(&dev->dev, "invalid frame len\n");
	159	phy->ndlc->hard_fault = 1;
	160	return -EBADMSG;
	161	}
	162
	163	*skb = alloc_skb(ST_NCI_SPI_MIN_SIZE + len, GFP_KERNEL);
164	if (*skb == NULL)
165	return -ENOMEM;
166
167	skb_reserve(*skb, ST_NCI_SPI_MIN_SIZE);
168	skb_put(*skb, ST_NCI_SPI_MIN_SIZE);
169	memcpy((*skb)->data, buf, ST_NCI_SPI_MIN_SIZE);
170
171	if (!len)
172	return 0;
173
174	spi_xfer.len = len;
175	r = spi_sync_transfer(dev, &spi_xfer, 1);
176	if (r < 0) {
177	kfree_skb(*skb);
178	return -EREMOTEIO;
179	}
180
181	skb_put(*skb, len);
182	memcpy((*skb)->data + ST_NCI_SPI_MIN_SIZE, buf, len);
183
184	SPI_DUMP_SKB("spi frame read", *skb);
185
186	return 0;
187	}
188
189	/*
190	* Reads an ndlc frame from the chip.
191	*
192	* On ST21NFCB, IRQ goes in idle state when read starts.
193	*/
194	static irqreturn_t st_nci_irq_thread_fn(int irq, void *phy_id)
195	{
196	struct st_nci_spi_phy *phy = phy_id;
197	struct spi_device *dev;
198	struct sk_buff *skb = NULL;
199	int r;
200
201	if (!phy \|\| !phy->ndlc \|\| irq != phy->spi_dev->irq) {
202	WARN_ON_ONCE(1);
203	return IRQ_NONE;
204	}
205
206	dev = phy->spi_dev;
207	dev_dbg(&dev->dev, "IRQ\n");
208
209	if (phy->ndlc->hard_fault)
210	return IRQ_HANDLED;
211
212	if (!phy->ndlc->powered) {
213	st_nci_spi_disable(phy);
214	return IRQ_HANDLED;
215	}
216
217	r = st_nci_spi_read(phy, &skb);
218	if (r == -EREMOTEIO \|\| r == -ENOMEM \|\| r == -EBADMSG)
219	return IRQ_HANDLED;
220
221	ndlc_recv(phy->ndlc, skb);
222
223	return IRQ_HANDLED;
224	}
225
226	static struct nfc_phy_ops spi_phy_ops = {
227	.write = st_nci_spi_write,
228	.enable = st_nci_spi_enable,
229	.disable = st_nci_spi_disable,
230	};
231
232	#ifdef CONFIG_OF
233	static int st_nci_spi_of_request_resources(struct spi_device *dev)
234	{
235	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);
236	struct device_node *pp;
237	int gpio;
238	int r;
239
240	pp = dev->dev.of_node;
241	if (!pp)
242	return -ENODEV;
243
244	/* Get GPIO from device tree */
245	gpio = of_get_named_gpio(pp, "reset-gpios", 0);
246	if (gpio < 0) {
247	nfc_err(&dev->dev,
248	"Failed to retrieve reset-gpios from device tree\n");
249	return gpio;
250	}
251
252	/* GPIO request and configuration */
253	r = devm_gpio_request_one(&dev->dev, gpio,
254	GPIOF_OUT_INIT_HIGH, "clf_reset");
255	if (r) {
256	nfc_err(&dev->dev, "Failed to request reset pin\n");
257	return r;
258	}
259	phy->gpio_reset = gpio;
260
261	phy->irq_polarity = irq_get_trigger_type(dev->irq);
262
263	return 0;
264	}
265	#else
266	static int st_nci_spi_of_request_resources(struct spi_device *dev)
267	{
268	return -ENODEV;
269	}
270	#endif
271
272	static int st_nci_spi_request_resources(struct spi_device *dev)
273	{
274	struct st_nci_nfc_platform_data *pdata;
275	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);
276	int r;
277
278	pdata = dev->dev.platform_data;
279	if (pdata == NULL) {
280	nfc_err(&dev->dev, "No platform data\n");
281	return -EINVAL;
282	}
283
284	/* store for later use */
285	phy->gpio_reset = pdata->gpio_reset;
286	phy->irq_polarity = pdata->irq_polarity;
287
288	r = devm_gpio_request_one(&dev->dev,
289	phy->gpio_reset, GPIOF_OUT_INIT_HIGH, "clf_reset");
290	if (r) {
291	pr_err("%s : reset gpio_request failed\n", __FILE__);
292	return r;
293	}
294
295	return 0;
296	}
297
298	static int st_nci_spi_probe(struct spi_device *dev)
299	{
300	struct st_nci_spi_phy *phy;
301	struct st_nci_nfc_platform_data *pdata;
302	int r;
303
304	dev_dbg(&dev->dev, "%s\n", __func__);
305	dev_dbg(&dev->dev, "IRQ: %d\n", dev->irq);
306
307	/* Check SPI platform functionnalities */
308	if (!dev) {
309	pr_debug("%s: dev is NULL. Device is not accessible.\n",
310	__func__);
311	return -ENODEV;
312	}
313
314	phy = devm_kzalloc(&dev->dev, sizeof(struct st_nci_spi_phy),
315	GFP_KERNEL);
316	if (!phy)
317	return -ENOMEM;
318
319	phy->spi_dev = dev;
320
321	spi_set_drvdata(dev, phy);
322
323	pdata = dev->dev.platform_data;
324	if (!pdata && dev->dev.of_node) {
325	r = st_nci_spi_of_request_resources(dev);
326	if (r) {
327	nfc_err(&dev->dev, "No platform data\n");
328	return r;
329	}
330	} else if (pdata) {
331	r = st_nci_spi_request_resources(dev);
332	if (r) {
333	nfc_err(&dev->dev,
334	"Cannot get platform resources\n");
335	return r;
336	}
337	} else {
338	nfc_err(&dev->dev,
339	"st_nci platform resources not available\n");
340	return -ENODEV;
341	}
342
343	r = ndlc_probe(phy, &spi_phy_ops, &dev->dev,
344	ST_NCI_FRAME_HEADROOM, ST_NCI_FRAME_TAILROOM,
345	&phy->ndlc);
346	if (r < 0) {
347	nfc_err(&dev->dev, "Unable to register ndlc layer\n");
348	return r;
349	}
350
351	r = devm_request_threaded_irq(&dev->dev, dev->irq, NULL,
352	st_nci_irq_thread_fn,
353	phy->irq_polarity \| IRQF_ONESHOT,
354	ST_NCI_SPI_DRIVER_NAME, phy);
355	if (r < 0)
356	nfc_err(&dev->dev, "Unable to register IRQ handler\n");
357
358	return r;
359	}
360
361	static int st_nci_spi_remove(struct spi_device *dev)
362	{
363	struct st_nci_spi_phy *phy = spi_get_drvdata(dev);
364
365	dev_dbg(&dev->dev, "%s\n", __func__);
366
367	ndlc_remove(phy->ndlc);
368
369	return 0;
370	}
371
372	#ifdef CONFIG_OF
373	static const struct of_device_id of_st_nci_spi_match[] = {
374	{ .compatible = "st,st21nfcb-spi", },
375	{}
376	};
377	MODULE_DEVICE_TABLE(of, of_st_nci_spi_match);
378	#endif
379
380	static struct spi_driver st_nci_spi_driver = {
381	.driver = {
382	.owner = THIS_MODULE,
383	.name = ST_NCI_SPI_DRIVER_NAME,
384	.of_match_table = of_match_ptr(of_st_nci_spi_match),
385	},
386	.probe = st_nci_spi_probe,
387	.id_table = st_nci_spi_id_table,
388	.remove = st_nci_spi_remove,
389	};
390
391	module_spi_driver(st_nci_spi_driver);
392
393	MODULE_LICENSE("GPL");
394	MODULE_DESCRIPTION(DRIVER_DESC);