[deliverable/linux.git] / net / nfc / core.c

/*
 * Copyright (C) 2011 Instituto Nokia de Tecnologia
 *
 * Authors:
 *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
 *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/nfc.h>

#include "nfc.h"

#define VERSION "0.1"

int nfc_devlist_generation;
DEFINE_MUTEX(nfc_devlist_mutex);

/**
 * nfc_dev_up - turn on the NFC device
 *
 * @dev: The nfc device to be turned on
 *
 * The device remains up until the nfc_dev_down function is called.
 */
int nfc_dev_up(struct nfc_dev *dev)
{
	int rc = 0;

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	if (dev->dev_up) {
		rc = -EALREADY;
		goto error;
	}

	if (dev->ops->dev_up)
		rc = dev->ops->dev_up(dev);

	if (!rc)
		dev->dev_up = true;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_dev_down - turn off the NFC device
 *
 * @dev: The nfc device to be turned off
 */
int nfc_dev_down(struct nfc_dev *dev)
{
	int rc = 0;

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	if (!dev->dev_up) {
		rc = -EALREADY;
		goto error;
	}

	if (dev->polling || dev->remote_activated) {
		rc = -EBUSY;
		goto error;
	}

	if (dev->ops->dev_down)
		dev->ops->dev_down(dev);

	dev->dev_up = false;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_start_poll - start polling for nfc targets
 *
 * @dev: The nfc device that must start polling
 * @protocols: bitset of nfc protocols that must be used for polling
 *
 * The device remains polling for targets until a target is found or
 * the nfc_stop_poll function is called.
 */
int nfc_start_poll(struct nfc_dev *dev, u32 protocols)
{
	int rc;

	pr_debug("dev_name=%s protocols=0x%x\n",
		 dev_name(&dev->dev), protocols);

	if (!protocols)
		return -EINVAL;

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	if (dev->polling) {
		rc = -EBUSY;
		goto error;
	}

	rc = dev->ops->start_poll(dev, protocols);
	if (!rc)
		dev->polling = true;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_stop_poll - stop polling for nfc targets
 *
 * @dev: The nfc device that must stop polling
 */
int nfc_stop_poll(struct nfc_dev *dev)
{
	int rc = 0;

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	if (!dev->polling) {
		rc = -EINVAL;
		goto error;
	}

	dev->ops->stop_poll(dev);
	dev->polling = false;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_activate_target - prepare the target for data exchange
 *
 * @dev: The nfc device that found the target
 * @target_idx: index of the target that must be activated
 * @protocol: nfc protocol that will be used for data exchange
 */
int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
{
	int rc;

	pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
		 dev_name(&dev->dev), target_idx, protocol);

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	rc = dev->ops->activate_target(dev, target_idx, protocol);
	if (!rc)
		dev->remote_activated = true;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_deactivate_target - deactivate a nfc target
 *
 * @dev: The nfc device that found the target
 * @target_idx: index of the target that must be deactivated
 */
int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
{
	int rc = 0;

	pr_debug("dev_name=%s target_idx=%u\n",
		 dev_name(&dev->dev), target_idx);

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		goto error;
	}

	dev->ops->deactivate_target(dev, target_idx);
	dev->remote_activated = false;

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_data_exchange - transceive data
 *
 * @dev: The nfc device that found the target
 * @target_idx: index of the target
 * @skb: data to be sent
 * @cb: callback called when the response is received
 * @cb_context: parameter for the callback function
 *
 * The user must wait for the callback before calling this function again.
 */
int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx,
					struct sk_buff *skb,
					data_exchange_cb_t cb,
					void *cb_context)
{
	int rc;

	pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
		 dev_name(&dev->dev), target_idx, skb->len);

	device_lock(&dev->dev);

	if (!device_is_registered(&dev->dev)) {
		rc = -ENODEV;
		kfree_skb(skb);
		goto error;
	}

	rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context);

error:
	device_unlock(&dev->dev);
	return rc;
}

/**
 * nfc_alloc_send_skb - allocate a skb for data exchange responses
 *
 * @size: size to allocate
 * @gfp: gfp flags
 */
struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
					unsigned int flags, unsigned int size,
					unsigned int *err)
{
	struct sk_buff *skb;
	unsigned int total_size;

	total_size = size +
		dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;

	skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
	if (skb)
		skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);

	return skb;
}

/**
 * nfc_alloc_recv_skb - allocate a skb for data exchange responses
 *
 * @size: size to allocate
 * @gfp: gfp flags
 */
struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
{
	struct sk_buff *skb;
	unsigned int total_size;

	total_size = size + 1;
	skb = alloc_skb(total_size, gfp);

	if (skb)
		skb_reserve(skb, 1);

	return skb;
}
EXPORT_SYMBOL(nfc_alloc_recv_skb);

/**
 * nfc_targets_found - inform that targets were found
 *
 * @dev: The nfc device that found the targets
 * @targets: array of nfc targets found
 * @ntargets: targets array size
 *
 * The device driver must call this function when one or many nfc targets
 * are found. After calling this function, the device driver must stop
 * polling for targets.
 */
int nfc_targets_found(struct nfc_dev *dev, struct nfc_target *targets,
							int n_targets)
{
	int i;

	pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);

	dev->polling = false;

	for (i = 0; i < n_targets; i++)
		targets[i].idx = dev->target_idx++;

	spin_lock_bh(&dev->targets_lock);

	dev->targets_generation++;

	kfree(dev->targets);
	dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target),
								GFP_ATOMIC);

	if (!dev->targets) {
		dev->n_targets = 0;
		spin_unlock_bh(&dev->targets_lock);
		return -ENOMEM;
	}

	dev->n_targets = n_targets;
	spin_unlock_bh(&dev->targets_lock);

	nfc_genl_targets_found(dev);

	return 0;
}
EXPORT_SYMBOL(nfc_targets_found);

static void nfc_release(struct device *d)
{
	struct nfc_dev *dev = to_nfc_dev(d);

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	nfc_genl_data_exit(&dev->genl_data);
	kfree(dev->targets);
	kfree(dev);
}

struct class nfc_class = {
	.name = "nfc",
	.dev_release = nfc_release,
};
EXPORT_SYMBOL(nfc_class);

static int match_idx(struct device *d, void *data)
{
	struct nfc_dev *dev = to_nfc_dev(d);
	unsigned *idx = data;

	return dev->idx == *idx;
}

struct nfc_dev *nfc_get_device(unsigned idx)
{
	struct device *d;

	d = class_find_device(&nfc_class, NULL, &idx, match_idx);
	if (!d)
		return NULL;

	return to_nfc_dev(d);
}

/**
 * nfc_allocate_device - allocate a new nfc device
 *
 * @ops: device operations
 * @supported_protocols: NFC protocols supported by the device
 */
struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
					u32 supported_protocols,
					int tx_headroom,
					int tx_tailroom)
{
	static atomic_t dev_no = ATOMIC_INIT(0);
	struct nfc_dev *dev;

	if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
		!ops->deactivate_target || !ops->data_exchange)
		return NULL;

	if (!supported_protocols)
		return NULL;

	dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
	if (!dev)
		return NULL;

	dev->dev.class = &nfc_class;
	dev->idx = atomic_inc_return(&dev_no) - 1;
	dev_set_name(&dev->dev, "nfc%d", dev->idx);
	device_initialize(&dev->dev);

	dev->ops = ops;
	dev->supported_protocols = supported_protocols;
	dev->tx_headroom = tx_headroom;
	dev->tx_tailroom = tx_tailroom;

	spin_lock_init(&dev->targets_lock);
	nfc_genl_data_init(&dev->genl_data);

	/* first generation must not be 0 */
	dev->targets_generation = 1;

	return dev;
}
EXPORT_SYMBOL(nfc_allocate_device);

/**
 * nfc_register_device - register a nfc device in the nfc subsystem
 *
 * @dev: The nfc device to register
 */
int nfc_register_device(struct nfc_dev *dev)
{
	int rc;

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	mutex_lock(&nfc_devlist_mutex);
	nfc_devlist_generation++;
	rc = device_add(&dev->dev);
	mutex_unlock(&nfc_devlist_mutex);

	if (rc < 0)
		return rc;

	rc = nfc_genl_device_added(dev);
	if (rc)
		pr_debug("The userspace won't be notified that the device %s was added\n",
			 dev_name(&dev->dev));

	return 0;
}
EXPORT_SYMBOL(nfc_register_device);

/**
 * nfc_unregister_device - unregister a nfc device in the nfc subsystem
 *
 * @dev: The nfc device to unregister
 */
void nfc_unregister_device(struct nfc_dev *dev)
{
	int rc;

	pr_debug("dev_name=%s\n", dev_name(&dev->dev));

	mutex_lock(&nfc_devlist_mutex);
	nfc_devlist_generation++;

	/* lock to avoid unregistering a device while an operation
	   is in progress */
	device_lock(&dev->dev);
	device_del(&dev->dev);
	device_unlock(&dev->dev);

	mutex_unlock(&nfc_devlist_mutex);

	rc = nfc_genl_device_removed(dev);
	if (rc)
		pr_debug("The userspace won't be notified that the device %s was removed\n",
			 dev_name(&dev->dev));

}
EXPORT_SYMBOL(nfc_unregister_device);

static int __init nfc_init(void)
{
	int rc;

	pr_info("NFC Core ver %s\n", VERSION);

	rc = class_register(&nfc_class);
	if (rc)
		return rc;

	rc = nfc_genl_init();
	if (rc)
		goto err_genl;

	/* the first generation must not be 0 */
	nfc_devlist_generation = 1;

	rc = rawsock_init();
	if (rc)
		goto err_rawsock;

	rc = af_nfc_init();
	if (rc)
		goto err_af_nfc;

	return 0;

err_af_nfc:
	rawsock_exit();
err_rawsock:
	nfc_genl_exit();
err_genl:
	class_unregister(&nfc_class);
	return rc;
}

static void __exit nfc_exit(void)
{
	af_nfc_exit();
	rawsock_exit();
	nfc_genl_exit();
	class_unregister(&nfc_class);
}

subsys_initcall(nfc_init);
module_exit(nfc_exit);

MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
MODULE_DESCRIPTION("NFC Core ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
Commit	Line	Data
3e256b8f LRV	1	/*
	2	* Copyright (C) 2011 Instituto Nokia de Tecnologia
	3	*
	4	* Authors:
	5	* Lauro Ramos Venancio <lauro.venancio@openbossa.org>
	6	* Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the
	20	* Free Software Foundation, Inc.,
	21	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	22	*/
	23
52858b51	24	#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
ed1e0ad8	25
3e256b8f LRV	26	#include <linux/init.h>
	27	#include <linux/kernel.h>
	28	#include <linux/module.h>
	29	#include <linux/slab.h>
7c7cd3bf	30	#include <linux/nfc.h>
3e256b8f LRV	31
	32	#include "nfc.h"
	33
	34	#define VERSION "0.1"
	35
	36	int nfc_devlist_generation;
	37	DEFINE_MUTEX(nfc_devlist_mutex);
	38
8b3fe7b5 IE	39	/**
	40	* nfc_dev_up - turn on the NFC device
	41	*
	42	* @dev: The nfc device to be turned on
	43	*
	44	* The device remains up until the nfc_dev_down function is called.
	45	*/
	46	int nfc_dev_up(struct nfc_dev *dev)
	47	{
	48	int rc = 0;
	49
20c239c1	50	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
8b3fe7b5 IE	51
	52	device_lock(&dev->dev);
	53
	54	if (!device_is_registered(&dev->dev)) {
	55	rc = -ENODEV;
	56	goto error;
	57	}
	58
	59	if (dev->dev_up) {
	60	rc = -EALREADY;
	61	goto error;
	62	}
	63
	64	if (dev->ops->dev_up)
	65	rc = dev->ops->dev_up(dev);
	66
	67	if (!rc)
	68	dev->dev_up = true;
	69
	70	error:
	71	device_unlock(&dev->dev);
	72	return rc;
	73	}
	74
	75	/**
	76	* nfc_dev_down - turn off the NFC device
	77	*
	78	* @dev: The nfc device to be turned off
	79	*/
	80	int nfc_dev_down(struct nfc_dev *dev)
	81	{
	82	int rc = 0;
	83
20c239c1	84	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
8b3fe7b5 IE	85
	86	device_lock(&dev->dev);
	87
	88	if (!device_is_registered(&dev->dev)) {
	89	rc = -ENODEV;
	90	goto error;
	91	}
	92
	93	if (!dev->dev_up) {
	94	rc = -EALREADY;
	95	goto error;
	96	}
	97
	98	if (dev->polling \|\| dev->remote_activated) {
	99	rc = -EBUSY;
	100	goto error;
	101	}
	102
	103	if (dev->ops->dev_down)
	104	dev->ops->dev_down(dev);
	105
	106	dev->dev_up = false;
	107
	108	error:
	109	device_unlock(&dev->dev);
	110	return rc;
	111	}
	112
3e256b8f LRV	113	/**
	114	* nfc_start_poll - start polling for nfc targets
	115	*
	116	* @dev: The nfc device that must start polling
	117	* @protocols: bitset of nfc protocols that must be used for polling
	118	*
	119	* The device remains polling for targets until a target is found or
	120	* the nfc_stop_poll function is called.
	121	*/
	122	int nfc_start_poll(struct nfc_dev *dev, u32 protocols)
	123	{
	124	int rc;
	125
20c239c1 JP	126	pr_debug("dev_name=%s protocols=0x%x\n",
20c239c1 JP	127	dev_name(&dev->dev), protocols);
3e256b8f LRV	128
	129	if (!protocols)
	130	return -EINVAL;
	131
	132	device_lock(&dev->dev);
	133
	134	if (!device_is_registered(&dev->dev)) {
	135	rc = -ENODEV;
	136	goto error;
	137	}
	138
	139	if (dev->polling) {
	140	rc = -EBUSY;
	141	goto error;
	142	}
	143
	144	rc = dev->ops->start_poll(dev, protocols);
	145	if (!rc)
	146	dev->polling = true;
	147
	148	error:
	149	device_unlock(&dev->dev);
	150	return rc;
	151	}
	152
	153	/**
	154	* nfc_stop_poll - stop polling for nfc targets
	155	*
	156	* @dev: The nfc device that must stop polling
	157	*/
	158	int nfc_stop_poll(struct nfc_dev *dev)
	159	{
	160	int rc = 0;
	161
20c239c1	162	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
3e256b8f LRV	163
	164	device_lock(&dev->dev);
	165
	166	if (!device_is_registered(&dev->dev)) {
	167	rc = -ENODEV;
	168	goto error;
	169	}
	170
	171	if (!dev->polling) {
	172	rc = -EINVAL;
	173	goto error;
	174	}
	175
	176	dev->ops->stop_poll(dev);
	177	dev->polling = false;
	178
	179	error:
	180	device_unlock(&dev->dev);
	181	return rc;
	182	}
	183
	184	/**
	185	* nfc_activate_target - prepare the target for data exchange
	186	*
	187	* @dev: The nfc device that found the target
	188	* @target_idx: index of the target that must be activated
	189	* @protocol: nfc protocol that will be used for data exchange
	190	*/
	191	int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
	192	{
	193	int rc;
	194
20c239c1 JP	195	pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
20c239c1 JP	196	dev_name(&dev->dev), target_idx, protocol);
3e256b8f LRV	197
	198	device_lock(&dev->dev);
	199
	200	if (!device_is_registered(&dev->dev)) {
	201	rc = -ENODEV;
	202	goto error;
	203	}
	204
	205	rc = dev->ops->activate_target(dev, target_idx, protocol);
8b3fe7b5 IE	206	if (!rc)
8b3fe7b5 IE	207	dev->remote_activated = true;
3e256b8f LRV	208
	209	error:
	210	device_unlock(&dev->dev);
	211	return rc;
	212	}
	213
	214	/**
	215	* nfc_deactivate_target - deactivate a nfc target
	216	*
	217	* @dev: The nfc device that found the target
	218	* @target_idx: index of the target that must be deactivated
	219	*/
	220	int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
	221	{
	222	int rc = 0;
	223
20c239c1 JP	224	pr_debug("dev_name=%s target_idx=%u\n",
20c239c1 JP	225	dev_name(&dev->dev), target_idx);
3e256b8f LRV	226
	227	device_lock(&dev->dev);
	228
	229	if (!device_is_registered(&dev->dev)) {
	230	rc = -ENODEV;
	231	goto error;
	232	}
	233
	234	dev->ops->deactivate_target(dev, target_idx);
8b3fe7b5	235	dev->remote_activated = false;
3e256b8f LRV	236
	237	error:
	238	device_unlock(&dev->dev);
	239	return rc;
	240	}
	241
	242	/**
	243	* nfc_data_exchange - transceive data
	244	*
	245	* @dev: The nfc device that found the target
	246	* @target_idx: index of the target
	247	* @skb: data to be sent
	248	* @cb: callback called when the response is received
	249	* @cb_context: parameter for the callback function
	250	*
	251	* The user must wait for the callback before calling this function again.
	252	*/
	253	int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx,
	254	struct sk_buff *skb,
	255	data_exchange_cb_t cb,
	256	void *cb_context)
	257	{
	258	int rc;
	259
20c239c1 JP	260	pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
20c239c1 JP	261	dev_name(&dev->dev), target_idx, skb->len);
3e256b8f LRV	262
	263	device_lock(&dev->dev);
	264
	265	if (!device_is_registered(&dev->dev)) {
	266	rc = -ENODEV;
	267	kfree_skb(skb);
	268	goto error;
	269	}
	270
	271	rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context);
	272
	273	error:
	274	device_unlock(&dev->dev);
	275	return rc;
	276	}
	277
	278	/**
7c7cd3bf	279	* nfc_alloc_send_skb - allocate a skb for data exchange responses
3e256b8f LRV	280	*
	281	* @size: size to allocate
	282	* @gfp: gfp flags
	283	*/
7c7cd3bf SO	284	struct sk_buff nfc_alloc_send_skb(struct nfc_dev dev, struct sock *sk,
	285	unsigned int flags, unsigned int size,
	286	unsigned int *err)
	287	{
	288	struct sk_buff *skb;
	289	unsigned int total_size;
	290
	291	total_size = size +
	292	dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	293
	294	skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
	295	if (skb)
	296	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	297
	298	return skb;
	299	}
	300
	301	/**
	302	* nfc_alloc_recv_skb - allocate a skb for data exchange responses
	303	*
	304	* @size: size to allocate
	305	* @gfp: gfp flags
	306	*/
	307	struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
3e256b8f LRV	308	{
	309	struct sk_buff *skb;
	310	unsigned int total_size;
	311
	312	total_size = size + 1;
	313	skb = alloc_skb(total_size, gfp);
	314
	315	if (skb)
	316	skb_reserve(skb, 1);
	317
	318	return skb;
	319	}
7c7cd3bf	320	EXPORT_SYMBOL(nfc_alloc_recv_skb);
3e256b8f	321
4d12b8b1 LRV	322	/**
	323	* nfc_targets_found - inform that targets were found
	324	*
	325	* @dev: The nfc device that found the targets
	326	* @targets: array of nfc targets found
	327	* @ntargets: targets array size
	328	*
	329	* The device driver must call this function when one or many nfc targets
	330	* are found. After calling this function, the device driver must stop
	331	* polling for targets.
	332	*/
	333	int nfc_targets_found(struct nfc_dev dev, struct nfc_target targets,
	334	int n_targets)
	335	{
	336	int i;
	337
20c239c1	338	pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);
4d12b8b1 LRV	339
	340	dev->polling = false;
	341
	342	for (i = 0; i < n_targets; i++)
	343	targets[i].idx = dev->target_idx++;
	344
	345	spin_lock_bh(&dev->targets_lock);
	346
	347	dev->targets_generation++;
	348
	349	kfree(dev->targets);
	350	dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target),
	351	GFP_ATOMIC);
	352
	353	if (!dev->targets) {
	354	dev->n_targets = 0;
	355	spin_unlock_bh(&dev->targets_lock);
	356	return -ENOMEM;
	357	}
	358
	359	dev->n_targets = n_targets;
	360	spin_unlock_bh(&dev->targets_lock);
	361
	362	nfc_genl_targets_found(dev);
	363
	364	return 0;
	365	}
	366	EXPORT_SYMBOL(nfc_targets_found);
	367
3e256b8f LRV	368	static void nfc_release(struct device *d)
	369	{
	370	struct nfc_dev *dev = to_nfc_dev(d);
	371
20c239c1	372	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
3e256b8f	373
4d12b8b1 LRV	374	nfc_genl_data_exit(&dev->genl_data);
4d12b8b1 LRV	375	kfree(dev->targets);
3e256b8f LRV	376	kfree(dev);
	377	}
	378
	379	struct class nfc_class = {
	380	.name = "nfc",
	381	.dev_release = nfc_release,
	382	};
	383	EXPORT_SYMBOL(nfc_class);
	384
	385	static int match_idx(struct device d, void data)
	386	{
	387	struct nfc_dev *dev = to_nfc_dev(d);
	388	unsigned *idx = data;
	389
	390	return dev->idx == *idx;
	391	}
	392
	393	struct nfc_dev *nfc_get_device(unsigned idx)
	394	{
	395	struct device *d;
	396
	397	d = class_find_device(&nfc_class, NULL, &idx, match_idx);
	398	if (!d)
	399	return NULL;
	400
	401	return to_nfc_dev(d);
	402	}
	403
	404	/**
	405	* nfc_allocate_device - allocate a new nfc device
	406	*
	407	* @ops: device operations
	408	* @supported_protocols: NFC protocols supported by the device
	409	*/
	410	struct nfc_dev nfc_allocate_device(struct nfc_ops ops,
e8753043 SO	411	u32 supported_protocols,
	412	int tx_headroom,
	413	int tx_tailroom)
3e256b8f LRV	414	{
	415	static atomic_t dev_no = ATOMIC_INIT(0);
	416	struct nfc_dev *dev;
	417
	418	if (!ops->start_poll \|\| !ops->stop_poll \|\| !ops->activate_target \|\|
	419	!ops->deactivate_target \|\| !ops->data_exchange)
	420	return NULL;
	421
	422	if (!supported_protocols)
	423	return NULL;
	424
	425	dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
	426	if (!dev)
	427	return NULL;
	428
	429	dev->dev.class = &nfc_class;
	430	dev->idx = atomic_inc_return(&dev_no) - 1;
	431	dev_set_name(&dev->dev, "nfc%d", dev->idx);
	432	device_initialize(&dev->dev);
	433
	434	dev->ops = ops;
	435	dev->supported_protocols = supported_protocols;
e8753043 SO	436	dev->tx_headroom = tx_headroom;
e8753043 SO	437	dev->tx_tailroom = tx_tailroom;
3e256b8f	438
4d12b8b1 LRV	439	spin_lock_init(&dev->targets_lock);
	440	nfc_genl_data_init(&dev->genl_data);
	441
	442	/* first generation must not be 0 */
	443	dev->targets_generation = 1;
	444
3e256b8f LRV	445	return dev;
	446	}
	447	EXPORT_SYMBOL(nfc_allocate_device);
	448
	449	/**
	450	* nfc_register_device - register a nfc device in the nfc subsystem
	451	*
	452	* @dev: The nfc device to register
	453	*/
	454	int nfc_register_device(struct nfc_dev *dev)
	455	{
	456	int rc;
	457
20c239c1	458	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
3e256b8f LRV	459
	460	mutex_lock(&nfc_devlist_mutex);
	461	nfc_devlist_generation++;
	462	rc = device_add(&dev->dev);
	463	mutex_unlock(&nfc_devlist_mutex);
	464
4d12b8b1 LRV	465	if (rc < 0)
	466	return rc;
	467
	468	rc = nfc_genl_device_added(dev);
	469	if (rc)
20c239c1 JP	470	pr_debug("The userspace won't be notified that the device %s was added\n",
20c239c1 JP	471	dev_name(&dev->dev));
4d12b8b1 LRV	472
4d12b8b1 LRV	473	return 0;
3e256b8f LRV	474	}
	475	EXPORT_SYMBOL(nfc_register_device);
	476
	477	/**
	478	* nfc_unregister_device - unregister a nfc device in the nfc subsystem
	479	*
	480	* @dev: The nfc device to unregister
	481	*/
	482	void nfc_unregister_device(struct nfc_dev *dev)
	483	{
4d12b8b1 LRV	484	int rc;
4d12b8b1 LRV	485
20c239c1	486	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
3e256b8f LRV	487
	488	mutex_lock(&nfc_devlist_mutex);
	489	nfc_devlist_generation++;
	490
	491	/* lock to avoid unregistering a device while an operation
	492	is in progress */
	493	device_lock(&dev->dev);
	494	device_del(&dev->dev);
	495	device_unlock(&dev->dev);
	496
	497	mutex_unlock(&nfc_devlist_mutex);
4d12b8b1 LRV	498
	499	rc = nfc_genl_device_removed(dev);
	500	if (rc)
20c239c1 JP	501	pr_debug("The userspace won't be notified that the device %s was removed\n",
20c239c1 JP	502	dev_name(&dev->dev));
4d12b8b1	503
3e256b8f LRV	504	}
	505	EXPORT_SYMBOL(nfc_unregister_device);
	506
	507	static int __init nfc_init(void)
	508	{
4d12b8b1 LRV	509	int rc;
4d12b8b1 LRV	510
ed1e0ad8	511	pr_info("NFC Core ver %s\n", VERSION);
3e256b8f	512
4d12b8b1 LRV	513	rc = class_register(&nfc_class);
	514	if (rc)
	515	return rc;
	516
	517	rc = nfc_genl_init();
	518	if (rc)
	519	goto err_genl;
	520
	521	/* the first generation must not be 0 */
	522	nfc_devlist_generation = 1;
	523
23b7869c LRV	524	rc = rawsock_init();
	525	if (rc)
	526	goto err_rawsock;
	527
c7fe3b52 AAJ	528	rc = af_nfc_init();
	529	if (rc)
	530	goto err_af_nfc;
	531
4d12b8b1 LRV	532	return 0;
4d12b8b1 LRV	533
c7fe3b52	534	err_af_nfc:
23b7869c LRV	535	rawsock_exit();
23b7869c LRV	536	err_rawsock:
c7fe3b52	537	nfc_genl_exit();
4d12b8b1 LRV	538	err_genl:
	539	class_unregister(&nfc_class);
	540	return rc;
3e256b8f LRV	541	}
	542
	543	static void __exit nfc_exit(void)
	544	{
c7fe3b52	545	af_nfc_exit();
23b7869c	546	rawsock_exit();
4d12b8b1	547	nfc_genl_exit();
3e256b8f LRV	548	class_unregister(&nfc_class);
	549	}
	550
	551	subsys_initcall(nfc_init);
	552	module_exit(nfc_exit);
	553
	554	MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
	555	MODULE_DESCRIPTION("NFC Core ver " VERSION);
	556	MODULE_VERSION(VERSION);
	557	MODULE_LICENSE("GPL");