Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1233 insertions, 0 deletions

diff --git a/kernel/net/nfc/core.c b/kernel/net/nfc/core.c
new file mode 100644
index 000000000..cff3f1614
--- /dev/null
+++ b/kernel/net/nfc/core.c
@@ -0,0 +1,1233 @@
+/*
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#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/rfkill.h>
+#include <linux/nfc.h>
+
+#include <net/genetlink.h>
+
+#include "nfc.h"
+
+#define VERSION "0.1"
+
+#define NFC_CHECK_PRES_FREQ_MS	2000
+
+int nfc_devlist_generation;
+DEFINE_MUTEX(nfc_devlist_mutex);
+
+/* NFC device ID bitmap */
+static DEFINE_IDA(nfc_index_ida);
+
+int nfc_fw_download(struct nfc_dev *dev, const char *firmware_name)
+{
+	int rc = 0;
+
+	pr_debug("%s do firmware %s\n", dev_name(&dev->dev), firmware_name);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->dev_up) {
+		rc = -EBUSY;
+		goto error;
+	}
+
+	if (!dev->ops->fw_download) {
+		rc = -EOPNOTSUPP;
+		goto error;
+	}
+
+	dev->fw_download_in_progress = true;
+	rc = dev->ops->fw_download(dev, firmware_name);
+	if (rc)
+		dev->fw_download_in_progress = false;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_fw_download_done - inform that a firmware download was completed
+ *
+ * @dev: The nfc device to which firmware was downloaded
+ * @firmware_name: The firmware filename
+ * @result: The positive value of a standard errno value
+ */
+int nfc_fw_download_done(struct nfc_dev *dev, const char *firmware_name,
+			 u32 result)
+{
+	dev->fw_download_in_progress = false;
+
+	return nfc_genl_fw_download_done(dev, firmware_name, result);
+}
+EXPORT_SYMBOL(nfc_fw_download_done);
+
+/**
+ * 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 (dev->rfkill && rfkill_blocked(dev->rfkill)) {
+		rc = -ERFKILL;
+		goto error;
+	}
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->fw_download_in_progress) {
+		rc = -EBUSY;
+		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;
+
+	/* We have to enable the device before discovering SEs */
+	if (dev->ops->discover_se && dev->ops->discover_se(dev))
+		pr_err("SE discovery failed\n");
+
+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->active_target) {
+		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;
+}
+
+static int nfc_rfkill_set_block(void *data, bool blocked)
+{
+	struct nfc_dev *dev = data;
+
+	pr_debug("%s blocked %d", dev_name(&dev->dev), blocked);
+
+	if (!blocked)
+		return 0;
+
+	nfc_dev_down(dev);
+
+	return 0;
+}
+
+static const struct rfkill_ops nfc_rfkill_ops = {
+	.set_block = nfc_rfkill_set_block,
+};
+
+/**
+ * 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 im_protocols, u32 tm_protocols)
+{
+	int rc;
+
+	pr_debug("dev_name %s initiator protocols 0x%x target protocols 0x%x\n",
+		 dev_name(&dev->dev), im_protocols, tm_protocols);
+
+	if (!im_protocols && !tm_protocols)
+		return -EINVAL;
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (!dev->dev_up) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->polling) {
+		rc = -EBUSY;
+		goto error;
+	}
+
+	rc = dev->ops->start_poll(dev, im_protocols, tm_protocols);
+	if (!rc) {
+		dev->polling = true;
+		dev->rf_mode = NFC_RF_NONE;
+	}
+
+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;
+	dev->rf_mode = NFC_RF_NONE;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx)
+{
+	int i;
+
+	for (i = 0; i < dev->n_targets; i++) {
+		if (dev->targets[i].idx == target_idx)
+			return &dev->targets[i];
+	}
+
+	return NULL;
+}
+
+int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
+{
+	int rc = 0;
+	u8 *gb;
+	size_t gb_len;
+	struct nfc_target *target;
+
+	pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
+
+	if (!dev->ops->dep_link_up)
+		return -EOPNOTSUPP;
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->dep_link_up == true) {
+		rc = -EALREADY;
+		goto error;
+	}
+
+	gb = nfc_llcp_general_bytes(dev, &gb_len);
+	if (gb_len > NFC_MAX_GT_LEN) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	target = nfc_find_target(dev, target_index);
+	if (target == NULL) {
+		rc = -ENOTCONN;
+		goto error;
+	}
+
+	rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len);
+	if (!rc) {
+		dev->active_target = target;
+		dev->rf_mode = NFC_RF_INITIATOR;
+	}
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+int nfc_dep_link_down(struct nfc_dev *dev)
+{
+	int rc = 0;
+
+	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
+
+	if (!dev->ops->dep_link_down)
+		return -EOPNOTSUPP;
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->dep_link_up == false) {
+		rc = -EALREADY;
+		goto error;
+	}
+
+	rc = dev->ops->dep_link_down(dev);
+	if (!rc) {
+		dev->dep_link_up = false;
+		dev->active_target = NULL;
+		dev->rf_mode = NFC_RF_NONE;
+		nfc_llcp_mac_is_down(dev);
+		nfc_genl_dep_link_down_event(dev);
+	}
+
+error:
+	device_unlock(&dev->dev);
+
+	return rc;
+}
+
+int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
+		       u8 comm_mode, u8 rf_mode)
+{
+	dev->dep_link_up = true;
+
+	if (!dev->active_target && rf_mode == NFC_RF_INITIATOR) {
+		struct nfc_target *target;
+
+		target = nfc_find_target(dev, target_idx);
+		if (target == NULL)
+			return -ENOTCONN;
+
+		dev->active_target = target;
+	}
+
+	dev->polling = false;
+	dev->rf_mode = rf_mode;
+
+	nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
+
+	return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
+}
+EXPORT_SYMBOL(nfc_dep_link_is_up);
+
+/**
+ * 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;
+	struct nfc_target *target;
+
+	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;
+	}
+
+	if (dev->active_target) {
+		rc = -EBUSY;
+		goto error;
+	}
+
+	target = nfc_find_target(dev, target_idx);
+	if (target == NULL) {
+		rc = -ENOTCONN;
+		goto error;
+	}
+
+	rc = dev->ops->activate_target(dev, target, protocol);
+	if (!rc) {
+		dev->active_target = target;
+		dev->rf_mode = NFC_RF_INITIATOR;
+
+		if (dev->ops->check_presence && !dev->shutting_down)
+			mod_timer(&dev->check_pres_timer, jiffies +
+				  msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
+	}
+
+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;
+	}
+
+	if (dev->active_target == NULL) {
+		rc = -ENOTCONN;
+		goto error;
+	}
+
+	if (dev->active_target->idx != target_idx) {
+		rc = -ENOTCONN;
+		goto error;
+	}
+
+	if (dev->ops->check_presence)
+		del_timer_sync(&dev->check_pres_timer);
+
+	dev->ops->deactivate_target(dev, dev->active_target);
+	dev->active_target = NULL;
+
+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;
+	}
+
+	if (dev->rf_mode == NFC_RF_INITIATOR && dev->active_target != NULL) {
+		if (dev->active_target->idx != target_idx) {
+			rc = -EADDRNOTAVAIL;
+			kfree_skb(skb);
+			goto error;
+		}
+
+		if (dev->ops->check_presence)
+			del_timer_sync(&dev->check_pres_timer);
+
+		rc = dev->ops->im_transceive(dev, dev->active_target, skb, cb,
+					     cb_context);
+
+		if (!rc && dev->ops->check_presence && !dev->shutting_down)
+			mod_timer(&dev->check_pres_timer, jiffies +
+				  msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
+	} else if (dev->rf_mode == NFC_RF_TARGET && dev->ops->tm_send != NULL) {
+		rc = dev->ops->tm_send(dev, skb);
+	} else {
+		rc = -ENOTCONN;
+		kfree_skb(skb);
+		goto error;
+	}
+
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+struct nfc_se *nfc_find_se(struct nfc_dev *dev, u32 se_idx)
+{
+	struct nfc_se *se;
+
+	list_for_each_entry(se, &dev->secure_elements, list)
+		if (se->idx == se_idx)
+			return se;
+
+	return NULL;
+}
+EXPORT_SYMBOL(nfc_find_se);
+
+int nfc_enable_se(struct nfc_dev *dev, u32 se_idx)
+{
+	struct nfc_se *se;
+	int rc;
+
+	pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (!dev->dev_up) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->polling) {
+		rc = -EBUSY;
+		goto error;
+	}
+
+	if (!dev->ops->enable_se || !dev->ops->disable_se) {
+		rc = -EOPNOTSUPP;
+		goto error;
+	}
+
+	se = nfc_find_se(dev, se_idx);
+	if (!se) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	if (se->state == NFC_SE_ENABLED) {
+		rc = -EALREADY;
+		goto error;
+	}
+
+	rc = dev->ops->enable_se(dev, se_idx);
+	if (rc >= 0)
+		se->state = NFC_SE_ENABLED;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+int nfc_disable_se(struct nfc_dev *dev, u32 se_idx)
+{
+	struct nfc_se *se;
+	int rc;
+
+	pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (!dev->dev_up) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (!dev->ops->enable_se || !dev->ops->disable_se) {
+		rc = -EOPNOTSUPP;
+		goto error;
+	}
+
+	se = nfc_find_se(dev, se_idx);
+	if (!se) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	if (se->state == NFC_SE_DISABLED) {
+		rc = -EALREADY;
+		goto error;
+	}
+
+	rc = dev->ops->disable_se(dev, se_idx);
+	if (rc >= 0)
+		se->state = NFC_SE_DISABLED;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
+{
+	pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
+
+	return nfc_llcp_set_remote_gb(dev, gb, gb_len);
+}
+EXPORT_SYMBOL(nfc_set_remote_general_bytes);
+
+u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, size_t *gb_len)
+{
+	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
+
+	return nfc_llcp_general_bytes(dev, gb_len);
+}
+EXPORT_SYMBOL(nfc_get_local_general_bytes);
+
+int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb)
+{
+	/* Only LLCP target mode for now */
+	if (dev->dep_link_up == false) {
+		kfree_skb(skb);
+		return -ENOLINK;
+	}
+
+	return nfc_llcp_data_received(dev, skb);
+}
+EXPORT_SYMBOL(nfc_tm_data_received);
+
+int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode,
+		     u8 *gb, size_t gb_len)
+{
+	int rc;
+
+	device_lock(&dev->dev);
+
+	dev->polling = false;
+
+	if (gb != NULL) {
+		rc = nfc_set_remote_general_bytes(dev, gb, gb_len);
+		if (rc < 0)
+			goto out;
+	}
+
+	dev->rf_mode = NFC_RF_TARGET;
+
+	if (protocol == NFC_PROTO_NFC_DEP_MASK)
+		nfc_dep_link_is_up(dev, 0, comm_mode, NFC_RF_TARGET);
+
+	rc = nfc_genl_tm_activated(dev, protocol);
+
+out:
+	device_unlock(&dev->dev);
+
+	return rc;
+}
+EXPORT_SYMBOL(nfc_tm_activated);
+
+int nfc_tm_deactivated(struct nfc_dev *dev)
+{
+	dev->dep_link_up = false;
+	dev->rf_mode = NFC_RF_NONE;
+
+	return nfc_genl_tm_deactivated(dev);
+}
+EXPORT_SYMBOL(nfc_tm_deactivated);
+
+/**
+ * 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.
+ * NOTE: This function can be called with targets=NULL and n_targets=0 to
+ * notify a driver error, meaning that the polling operation cannot complete.
+ * IMPORTANT: this function must not be called from an atomic context.
+ * In addition, it must also not be called from a context that would prevent
+ * the NFC Core to call other nfc ops entry point concurrently.
+ */
+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);
+
+	for (i = 0; i < n_targets; i++)
+		targets[i].idx = dev->target_next_idx++;
+
+	device_lock(&dev->dev);
+
+	if (dev->polling == false) {
+		device_unlock(&dev->dev);
+		return 0;
+	}
+
+	dev->polling = false;
+
+	dev->targets_generation++;
+
+	kfree(dev->targets);
+	dev->targets = NULL;
+
+	if (targets) {
+		dev->targets = kmemdup(targets,
+				       n_targets * sizeof(struct nfc_target),
+				       GFP_ATOMIC);
+
+		if (!dev->targets) {
+			dev->n_targets = 0;
+			device_unlock(&dev->dev);
+			return -ENOMEM;
+		}
+	}
+
+	dev->n_targets = n_targets;
+	device_unlock(&dev->dev);
+
+	nfc_genl_targets_found(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(nfc_targets_found);
+
+/**
+ * nfc_target_lost - inform that an activated target went out of field
+ *
+ * @dev: The nfc device that had the activated target in field
+ * @target_idx: the nfc index of the target
+ *
+ * The device driver must call this function when the activated target
+ * goes out of the field.
+ * IMPORTANT: this function must not be called from an atomic context.
+ * In addition, it must also not be called from a context that would prevent
+ * the NFC Core to call other nfc ops entry point concurrently.
+ */
+int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
+{
+	struct nfc_target *tg;
+	int i;
+
+	pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
+
+	device_lock(&dev->dev);
+
+	for (i = 0; i < dev->n_targets; i++) {
+		tg = &dev->targets[i];
+		if (tg->idx == target_idx)
+			break;
+	}
+
+	if (i == dev->n_targets) {
+		device_unlock(&dev->dev);
+		return -EINVAL;
+	}
+
+	dev->targets_generation++;
+	dev->n_targets--;
+	dev->active_target = NULL;
+
+	if (dev->n_targets) {
+		memcpy(&dev->targets[i], &dev->targets[i + 1],
+		       (dev->n_targets - i) * sizeof(struct nfc_target));
+	} else {
+		kfree(dev->targets);
+		dev->targets = NULL;
+	}
+
+	device_unlock(&dev->dev);
+
+	nfc_genl_target_lost(dev, target_idx);
+
+	return 0;
+}
+EXPORT_SYMBOL(nfc_target_lost);
+
+inline void nfc_driver_failure(struct nfc_dev *dev, int err)
+{
+	nfc_targets_found(dev, NULL, 0);
+}
+EXPORT_SYMBOL(nfc_driver_failure);
+
+int nfc_add_se(struct nfc_dev *dev, u32 se_idx, u16 type)
+{
+	struct nfc_se *se;
+	int rc;
+
+	pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+	se = nfc_find_se(dev, se_idx);
+	if (se)
+		return -EALREADY;
+
+	se = kzalloc(sizeof(struct nfc_se), GFP_KERNEL);
+	if (!se)
+		return -ENOMEM;
+
+	se->idx = se_idx;
+	se->type = type;
+	se->state = NFC_SE_DISABLED;
+	INIT_LIST_HEAD(&se->list);
+
+	list_add(&se->list, &dev->secure_elements);
+
+	rc = nfc_genl_se_added(dev, se_idx, type);
+	if (rc < 0) {
+		list_del(&se->list);
+		kfree(se);
+
+		return rc;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(nfc_add_se);
+
+int nfc_remove_se(struct nfc_dev *dev, u32 se_idx)
+{
+	struct nfc_se *se, *n;
+	int rc;
+
+	pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+	list_for_each_entry_safe(se, n, &dev->secure_elements, list)
+		if (se->idx == se_idx) {
+			rc = nfc_genl_se_removed(dev, se_idx);
+			if (rc < 0)
+				return rc;
+
+			list_del(&se->list);
+			kfree(se);
+
+			return 0;
+		}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL(nfc_remove_se);
+
+int nfc_se_transaction(struct nfc_dev *dev, u8 se_idx,
+		       struct nfc_evt_transaction *evt_transaction)
+{
+	int rc;
+
+	pr_debug("transaction: %x\n", se_idx);
+
+	device_lock(&dev->dev);
+
+	if (!evt_transaction) {
+		rc = -EPROTO;
+		goto out;
+	}
+
+	rc = nfc_genl_se_transaction(dev, se_idx, evt_transaction);
+out:
+	device_unlock(&dev->dev);
+	return rc;
+}
+EXPORT_SYMBOL(nfc_se_transaction);
+
+static void nfc_release(struct device *d)
+{
+	struct nfc_dev *dev = to_nfc_dev(d);
+	struct nfc_se *se, *n;
+
+	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
+
+	nfc_genl_data_exit(&dev->genl_data);
+	kfree(dev->targets);
+
+	list_for_each_entry_safe(se, n, &dev->secure_elements, list) {
+			nfc_genl_se_removed(dev, se->idx);
+			list_del(&se->list);
+			kfree(se);
+	}
+
+	kfree(dev);
+}
+
+static void nfc_check_pres_work(struct work_struct *work)
+{
+	struct nfc_dev *dev = container_of(work, struct nfc_dev,
+					   check_pres_work);
+	int rc;
+
+	device_lock(&dev->dev);
+
+	if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) {
+		rc = dev->ops->check_presence(dev, dev->active_target);
+		if (rc == -EOPNOTSUPP)
+			goto exit;
+		if (rc) {
+			u32 active_target_idx = dev->active_target->idx;
+			device_unlock(&dev->dev);
+			nfc_target_lost(dev, active_target_idx);
+			return;
+		}
+
+		if (!dev->shutting_down)
+			mod_timer(&dev->check_pres_timer, jiffies +
+				  msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
+	}
+
+exit:
+	device_unlock(&dev->dev);
+}
+
+static void nfc_check_pres_timeout(unsigned long data)
+{
+	struct nfc_dev *dev = (struct nfc_dev *)data;
+
+	schedule_work(&dev->check_pres_work);
+}
+
+struct class nfc_class = {
+	.name = "nfc",
+	.dev_release = nfc_release,
+};
+EXPORT_SYMBOL(nfc_class);
+
+static int match_idx(struct device *d, const void *data)
+{
+	struct nfc_dev *dev = to_nfc_dev(d);
+	const unsigned int *idx = data;
+
+	return dev->idx == *idx;
+}
+
+struct nfc_dev *nfc_get_device(unsigned int 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)
+{
+	struct nfc_dev *dev;
+
+	if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
+	    !ops->deactivate_target || !ops->im_transceive)
+		return NULL;
+
+	if (!supported_protocols)
+		return NULL;
+
+	dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	dev->ops = ops;
+	dev->supported_protocols = supported_protocols;
+	dev->tx_headroom = tx_headroom;
+	dev->tx_tailroom = tx_tailroom;
+	INIT_LIST_HEAD(&dev->secure_elements);
+
+	nfc_genl_data_init(&dev->genl_data);
+
+	dev->rf_mode = NFC_RF_NONE;
+
+	/* first generation must not be 0 */
+	dev->targets_generation = 1;
+
+	if (ops->check_presence) {
+		init_timer(&dev->check_pres_timer);
+		dev->check_pres_timer.data = (unsigned long)dev;
+		dev->check_pres_timer.function = nfc_check_pres_timeout;
+
+		INIT_WORK(&dev->check_pres_work, nfc_check_pres_work);
+	}
+
+	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));
+
+	dev->idx = ida_simple_get(&nfc_index_ida, 0, 0, GFP_KERNEL);
+	if (dev->idx < 0)
+		return dev->idx;
+
+	dev->dev.class = &nfc_class;
+	dev_set_name(&dev->dev, "nfc%d", dev->idx);
+	device_initialize(&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_llcp_register_device(dev);
+	if (rc)
+		pr_err("Could not register llcp device\n");
+
+	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));
+
+	dev->rfkill = rfkill_alloc(dev_name(&dev->dev), &dev->dev,
+				   RFKILL_TYPE_NFC, &nfc_rfkill_ops, dev);
+	if (dev->rfkill) {
+		if (rfkill_register(dev->rfkill) < 0) {
+			rfkill_destroy(dev->rfkill);
+			dev->rfkill = NULL;
+		}
+	}
+
+	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, id;
+
+	pr_debug("dev_name=%s\n", dev_name(&dev->dev));
+
+	id = dev->idx;
+
+	if (dev->rfkill) {
+		rfkill_unregister(dev->rfkill);
+		rfkill_destroy(dev->rfkill);
+	}
+
+	if (dev->ops->check_presence) {
+		device_lock(&dev->dev);
+		dev->shutting_down = true;
+		device_unlock(&dev->dev);
+		del_timer_sync(&dev->check_pres_timer);
+		cancel_work_sync(&dev->check_pres_work);
+	}
+
+	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));
+
+	nfc_llcp_unregister_device(dev);
+
+	mutex_lock(&nfc_devlist_mutex);
+	nfc_devlist_generation++;
+	device_del(&dev->dev);
+	mutex_unlock(&nfc_devlist_mutex);
+
+	ida_simple_remove(&nfc_index_ida, id);
+}
+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 = nfc_llcp_init();
+	if (rc)
+		goto err_llcp_sock;
+
+	rc = af_nfc_init();
+	if (rc)
+		goto err_af_nfc;
+
+	return 0;
+
+err_af_nfc:
+	nfc_llcp_exit();
+err_llcp_sock:
+	rawsock_exit();
+err_rawsock:
+	nfc_genl_exit();
+err_genl:
+	class_unregister(&nfc_class);
+	return rc;
+}
+
+static void __exit nfc_exit(void)
+{
+	af_nfc_exit();
+	nfc_llcp_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");
+MODULE_ALIAS_NETPROTO(PF_NFC);
+MODULE_ALIAS_GENL_FAMILY(NFC_GENL_NAME);