1 files changed, 879 insertions, 0 deletions

diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
new file mode 100644
index 00000000..9ec065bb
--- /dev/null
+++ b/net/nfc/nci/core.c
@@ -0,0 +1,879 @@
+/*
+ *  The NFC Controller Interface is the communication protocol between an
+ *  NFC Controller (NFCC) and a Device Host (DH).
+ *
+ *  Copyright (C) 2011 Texas Instruments, Inc.
+ *
+ *  Written by Ilan Elias <ilane@ti.com>
+ *
+ *  Acknowledgements:
+ *  This file is based on hci_core.c, which was written
+ *  by Maxim Krasnyansky.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms 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, 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/types.h>
+#include <linux/workqueue.h>
+#include <linux/completion.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/bitops.h>
+#include <linux/skbuff.h>
+
+#include "../nfc.h"
+#include <net/nfc/nci.h>
+#include <net/nfc/nci_core.h>
+#include <linux/nfc.h>
+
+static void nci_cmd_work(struct work_struct *work);
+static void nci_rx_work(struct work_struct *work);
+static void nci_tx_work(struct work_struct *work);
+
+/* ---- NCI requests ---- */
+
+void nci_req_complete(struct nci_dev *ndev, int result)
+{
+	if (ndev->req_status == NCI_REQ_PEND) {
+		ndev->req_result = result;
+		ndev->req_status = NCI_REQ_DONE;
+		complete(&ndev->req_completion);
+	}
+}
+
+static void nci_req_cancel(struct nci_dev *ndev, int err)
+{
+	if (ndev->req_status == NCI_REQ_PEND) {
+		ndev->req_result = err;
+		ndev->req_status = NCI_REQ_CANCELED;
+		complete(&ndev->req_completion);
+	}
+}
+
+/* Execute request and wait for completion. */
+static int __nci_request(struct nci_dev *ndev,
+			 void (*req)(struct nci_dev *ndev, unsigned long opt),
+			 unsigned long opt, __u32 timeout)
+{
+	int rc = 0;
+	long completion_rc;
+
+	ndev->req_status = NCI_REQ_PEND;
+
+	init_completion(&ndev->req_completion);
+	req(ndev, opt);
+	completion_rc =
+		wait_for_completion_interruptible_timeout(&ndev->req_completion,
+							  timeout);
+
+	pr_debug("wait_for_completion return %ld\n", completion_rc);
+
+	if (completion_rc > 0) {
+		switch (ndev->req_status) {
+		case NCI_REQ_DONE:
+			rc = nci_to_errno(ndev->req_result);
+			break;
+
+		case NCI_REQ_CANCELED:
+			rc = -ndev->req_result;
+			break;
+
+		default:
+			rc = -ETIMEDOUT;
+			break;
+		}
+	} else {
+		pr_err("wait_for_completion_interruptible_timeout failed %ld\n",
+		       completion_rc);
+
+		rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc));
+	}
+
+	ndev->req_status = ndev->req_result = 0;
+
+	return rc;
+}
+
+static inline int nci_request(struct nci_dev *ndev,
+			      void (*req)(struct nci_dev *ndev,
+					  unsigned long opt),
+			      unsigned long opt, __u32 timeout)
+{
+	int rc;
+
+	if (!test_bit(NCI_UP, &ndev->flags))
+		return -ENETDOWN;
+
+	/* Serialize all requests */
+	mutex_lock(&ndev->req_lock);
+	rc = __nci_request(ndev, req, opt, timeout);
+	mutex_unlock(&ndev->req_lock);
+
+	return rc;
+}
+
+static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
+{
+	struct nci_core_reset_cmd cmd;
+
+	cmd.reset_type = NCI_RESET_TYPE_RESET_CONFIG;
+	nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 1, &cmd);
+}
+
+static void nci_init_req(struct nci_dev *ndev, unsigned long opt)
+{
+	nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
+}
+
+static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt)
+{
+	struct nci_rf_disc_map_cmd cmd;
+	struct disc_map_config *cfg = cmd.mapping_configs;
+	__u8 *num = &cmd.num_mapping_configs;
+	int i;
+
+	/* set rf mapping configurations */
+	*num = 0;
+
+	/* by default mapping is set to NCI_RF_INTERFACE_FRAME */
+	for (i = 0; i < ndev->num_supported_rf_interfaces; i++) {
+		if (ndev->supported_rf_interfaces[i] ==
+		    NCI_RF_INTERFACE_ISO_DEP) {
+			cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
+			cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
+				NCI_DISC_MAP_MODE_LISTEN;
+			cfg[*num].rf_interface = NCI_RF_INTERFACE_ISO_DEP;
+			(*num)++;
+		} else if (ndev->supported_rf_interfaces[i] ==
+			   NCI_RF_INTERFACE_NFC_DEP) {
+			cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
+			cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
+				NCI_DISC_MAP_MODE_LISTEN;
+			cfg[*num].rf_interface = NCI_RF_INTERFACE_NFC_DEP;
+			(*num)++;
+		}
+
+		if (*num == NCI_MAX_NUM_MAPPING_CONFIGS)
+			break;
+	}
+
+	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
+		     (1 + ((*num) * sizeof(struct disc_map_config))), &cmd);
+}
+
+static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt)
+{
+	struct nci_rf_disc_cmd cmd;
+	__u32 protocols = opt;
+
+	cmd.num_disc_configs = 0;
+
+	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
+	    (protocols & NFC_PROTO_JEWEL_MASK
+	     || protocols & NFC_PROTO_MIFARE_MASK
+	     || protocols & NFC_PROTO_ISO14443_MASK
+	     || protocols & NFC_PROTO_NFC_DEP_MASK)) {
+		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
+			NCI_NFC_A_PASSIVE_POLL_MODE;
+		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
+		cmd.num_disc_configs++;
+	}
+
+	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
+	    (protocols & NFC_PROTO_ISO14443_MASK)) {
+		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
+			NCI_NFC_B_PASSIVE_POLL_MODE;
+		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
+		cmd.num_disc_configs++;
+	}
+
+	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
+	    (protocols & NFC_PROTO_FELICA_MASK
+	     || protocols & NFC_PROTO_NFC_DEP_MASK)) {
+		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
+			NCI_NFC_F_PASSIVE_POLL_MODE;
+		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
+		cmd.num_disc_configs++;
+	}
+
+	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD,
+		     (1 + (cmd.num_disc_configs * sizeof(struct disc_config))),
+		     &cmd);
+}
+
+struct nci_rf_discover_select_param {
+	__u8	rf_discovery_id;
+	__u8	rf_protocol;
+};
+
+static void nci_rf_discover_select_req(struct nci_dev *ndev, unsigned long opt)
+{
+	struct nci_rf_discover_select_param *param =
+		(struct nci_rf_discover_select_param *)opt;
+	struct nci_rf_discover_select_cmd cmd;
+
+	cmd.rf_discovery_id = param->rf_discovery_id;
+	cmd.rf_protocol = param->rf_protocol;
+
+	switch (cmd.rf_protocol) {
+	case NCI_RF_PROTOCOL_ISO_DEP:
+		cmd.rf_interface = NCI_RF_INTERFACE_ISO_DEP;
+		break;
+
+	case NCI_RF_PROTOCOL_NFC_DEP:
+		cmd.rf_interface = NCI_RF_INTERFACE_NFC_DEP;
+		break;
+
+	default:
+		cmd.rf_interface = NCI_RF_INTERFACE_FRAME;
+		break;
+	}
+
+	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_SELECT_CMD,
+		     sizeof(struct nci_rf_discover_select_cmd), &cmd);
+}
+
+static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt)
+{
+	struct nci_rf_deactivate_cmd cmd;
+
+	cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE;
+
+	nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD,
+		     sizeof(struct nci_rf_deactivate_cmd), &cmd);
+}
+
+static int nci_open_device(struct nci_dev *ndev)
+{
+	int rc = 0;
+
+	mutex_lock(&ndev->req_lock);
+
+	if (test_bit(NCI_UP, &ndev->flags)) {
+		rc = -EALREADY;
+		goto done;
+	}
+
+	if (ndev->ops->open(ndev)) {
+		rc = -EIO;
+		goto done;
+	}
+
+	atomic_set(&ndev->cmd_cnt, 1);
+
+	set_bit(NCI_INIT, &ndev->flags);
+
+	rc = __nci_request(ndev, nci_reset_req, 0,
+			   msecs_to_jiffies(NCI_RESET_TIMEOUT));
+
+	if (!rc) {
+		rc = __nci_request(ndev, nci_init_req, 0,
+				   msecs_to_jiffies(NCI_INIT_TIMEOUT));
+	}
+
+	if (!rc) {
+		rc = __nci_request(ndev, nci_init_complete_req, 0,
+				   msecs_to_jiffies(NCI_INIT_TIMEOUT));
+	}
+
+	clear_bit(NCI_INIT, &ndev->flags);
+
+	if (!rc) {
+		set_bit(NCI_UP, &ndev->flags);
+		nci_clear_target_list(ndev);
+		atomic_set(&ndev->state, NCI_IDLE);
+	} else {
+		/* Init failed, cleanup */
+		skb_queue_purge(&ndev->cmd_q);
+		skb_queue_purge(&ndev->rx_q);
+		skb_queue_purge(&ndev->tx_q);
+
+		ndev->ops->close(ndev);
+		ndev->flags = 0;
+	}
+
+done:
+	mutex_unlock(&ndev->req_lock);
+	return rc;
+}
+
+static int nci_close_device(struct nci_dev *ndev)
+{
+	nci_req_cancel(ndev, ENODEV);
+	mutex_lock(&ndev->req_lock);
+
+	if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
+		del_timer_sync(&ndev->cmd_timer);
+		del_timer_sync(&ndev->data_timer);
+		mutex_unlock(&ndev->req_lock);
+		return 0;
+	}
+
+	/* Drop RX and TX queues */
+	skb_queue_purge(&ndev->rx_q);
+	skb_queue_purge(&ndev->tx_q);
+
+	/* Flush RX and TX wq */
+	flush_workqueue(ndev->rx_wq);
+	flush_workqueue(ndev->tx_wq);
+
+	/* Reset device */
+	skb_queue_purge(&ndev->cmd_q);
+	atomic_set(&ndev->cmd_cnt, 1);
+
+	set_bit(NCI_INIT, &ndev->flags);
+	__nci_request(ndev, nci_reset_req, 0,
+		      msecs_to_jiffies(NCI_RESET_TIMEOUT));
+	clear_bit(NCI_INIT, &ndev->flags);
+
+	/* Flush cmd wq */
+	flush_workqueue(ndev->cmd_wq);
+
+	/* After this point our queues are empty
+	 * and no works are scheduled. */
+	ndev->ops->close(ndev);
+
+	/* Clear flags */
+	ndev->flags = 0;
+
+	mutex_unlock(&ndev->req_lock);
+
+	return 0;
+}
+
+/* NCI command timer function */
+static void nci_cmd_timer(unsigned long arg)
+{
+	struct nci_dev *ndev = (void *) arg;
+
+	atomic_set(&ndev->cmd_cnt, 1);
+	queue_work(ndev->cmd_wq, &ndev->cmd_work);
+}
+
+/* NCI data exchange timer function */
+static void nci_data_timer(unsigned long arg)
+{
+	struct nci_dev *ndev = (void *) arg;
+
+	set_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
+	queue_work(ndev->rx_wq, &ndev->rx_work);
+}
+
+static int nci_dev_up(struct nfc_dev *nfc_dev)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+	return nci_open_device(ndev);
+}
+
+static int nci_dev_down(struct nfc_dev *nfc_dev)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+	return nci_close_device(ndev);
+}
+
+static int nci_start_poll(struct nfc_dev *nfc_dev, __u32 protocols)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+	int rc;
+
+	if ((atomic_read(&ndev->state) == NCI_DISCOVERY) ||
+	    (atomic_read(&ndev->state) == NCI_W4_ALL_DISCOVERIES)) {
+		pr_err("unable to start poll, since poll is already active\n");
+		return -EBUSY;
+	}
+
+	if (ndev->target_active_prot) {
+		pr_err("there is an active target\n");
+		return -EBUSY;
+	}
+
+	if ((atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) ||
+	    (atomic_read(&ndev->state) == NCI_POLL_ACTIVE)) {
+		pr_debug("target active or w4 select, implicitly deactivate\n");
+
+		rc = nci_request(ndev, nci_rf_deactivate_req, 0,
+				 msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
+		if (rc)
+			return -EBUSY;
+	}
+
+	rc = nci_request(ndev, nci_rf_discover_req, protocols,
+			 msecs_to_jiffies(NCI_RF_DISC_TIMEOUT));
+
+	if (!rc)
+		ndev->poll_prots = protocols;
+
+	return rc;
+}
+
+static void nci_stop_poll(struct nfc_dev *nfc_dev)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+	if ((atomic_read(&ndev->state) != NCI_DISCOVERY) &&
+	    (atomic_read(&ndev->state) != NCI_W4_ALL_DISCOVERIES)) {
+		pr_err("unable to stop poll, since poll is not active\n");
+		return;
+	}
+
+	nci_request(ndev, nci_rf_deactivate_req, 0,
+		    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
+}
+
+static int nci_activate_target(struct nfc_dev *nfc_dev, __u32 target_idx,
+			       __u32 protocol)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+	struct nci_rf_discover_select_param param;
+	struct nfc_target *target = NULL;
+	int i;
+	int rc = 0;
+
+	pr_debug("target_idx %d, protocol 0x%x\n", target_idx, protocol);
+
+	if ((atomic_read(&ndev->state) != NCI_W4_HOST_SELECT) &&
+	    (atomic_read(&ndev->state) != NCI_POLL_ACTIVE)) {
+		pr_err("there is no available target to activate\n");
+		return -EINVAL;
+	}
+
+	if (ndev->target_active_prot) {
+		pr_err("there is already an active target\n");
+		return -EBUSY;
+	}
+
+	for (i = 0; i < ndev->n_targets; i++) {
+		if (ndev->targets[i].idx == target_idx) {
+			target = &ndev->targets[i];
+			break;
+		}
+	}
+
+	if (!target) {
+		pr_err("unable to find the selected target\n");
+		return -EINVAL;
+	}
+
+	if (!(target->supported_protocols & (1 << protocol))) {
+		pr_err("target does not support the requested protocol 0x%x\n",
+		       protocol);
+		return -EINVAL;
+	}
+
+	if (atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) {
+		param.rf_discovery_id = target->idx;
+
+		if (protocol == NFC_PROTO_JEWEL)
+			param.rf_protocol = NCI_RF_PROTOCOL_T1T;
+		else if (protocol == NFC_PROTO_MIFARE)
+			param.rf_protocol = NCI_RF_PROTOCOL_T2T;
+		else if (protocol == NFC_PROTO_FELICA)
+			param.rf_protocol = NCI_RF_PROTOCOL_T3T;
+		else if (protocol == NFC_PROTO_ISO14443)
+			param.rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
+		else
+			param.rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
+
+		rc = nci_request(ndev, nci_rf_discover_select_req,
+				 (unsigned long)&param,
+				 msecs_to_jiffies(NCI_RF_DISC_SELECT_TIMEOUT));
+	}
+
+	if (!rc)
+		ndev->target_active_prot = protocol;
+
+	return rc;
+}
+
+static void nci_deactivate_target(struct nfc_dev *nfc_dev, __u32 target_idx)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+	pr_debug("target_idx %d\n", target_idx);
+
+	if (!ndev->target_active_prot) {
+		pr_err("unable to deactivate target, no active target\n");
+		return;
+	}
+
+	ndev->target_active_prot = 0;
+
+	if (atomic_read(&ndev->state) == NCI_POLL_ACTIVE) {
+		nci_request(ndev, nci_rf_deactivate_req, 0,
+			    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
+	}
+}
+
+static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
+			     struct sk_buff *skb,
+			     data_exchange_cb_t cb, void *cb_context)
+{
+	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+	int rc;
+
+	pr_debug("target_idx %d, len %d\n", target_idx, skb->len);
+
+	if (!ndev->target_active_prot) {
+		pr_err("unable to exchange data, no active target\n");
+		return -EINVAL;
+	}
+
+	if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
+		return -EBUSY;
+
+	/* store cb and context to be used on receiving data */
+	ndev->data_exchange_cb = cb;
+	ndev->data_exchange_cb_context = cb_context;
+
+	rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb);
+	if (rc)
+		clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
+
+	return rc;
+}
+
+static struct nfc_ops nci_nfc_ops = {
+	.dev_up = nci_dev_up,
+	.dev_down = nci_dev_down,
+	.start_poll = nci_start_poll,
+	.stop_poll = nci_stop_poll,
+	.activate_target = nci_activate_target,
+	.deactivate_target = nci_deactivate_target,
+	.data_exchange = nci_data_exchange,
+};
+
+/* ---- Interface to NCI drivers ---- */
+
+/**
+ * nci_allocate_device - allocate a new nci device
+ *
+ * @ops: device operations
+ * @supported_protocols: NFC protocols supported by the device
+ */
+struct nci_dev *nci_allocate_device(struct nci_ops *ops,
+				    __u32 supported_protocols,
+				    int tx_headroom, int tx_tailroom)
+{
+	struct nci_dev *ndev;
+
+	pr_debug("supported_protocols 0x%x\n", supported_protocols);
+
+	if (!ops->open || !ops->close || !ops->send)
+		return NULL;
+
+	if (!supported_protocols)
+		return NULL;
+
+	ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
+	if (!ndev)
+		return NULL;
+
+	ndev->ops = ops;
+	ndev->tx_headroom = tx_headroom;
+	ndev->tx_tailroom = tx_tailroom;
+
+	ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
+					    supported_protocols,
+					    tx_headroom + NCI_DATA_HDR_SIZE,
+					    tx_tailroom);
+	if (!ndev->nfc_dev)
+		goto free_exit;
+
+	nfc_set_drvdata(ndev->nfc_dev, ndev);
+
+	return ndev;
+
+free_exit:
+	kfree(ndev);
+	return NULL;
+}
+EXPORT_SYMBOL(nci_allocate_device);
+
+/**
+ * nci_free_device - deallocate nci device
+ *
+ * @ndev: The nci device to deallocate
+ */
+void nci_free_device(struct nci_dev *ndev)
+{
+	nfc_free_device(ndev->nfc_dev);
+	kfree(ndev);
+}
+EXPORT_SYMBOL(nci_free_device);
+
+/**
+ * nci_register_device - register a nci device in the nfc subsystem
+ *
+ * @dev: The nci device to register
+ */
+int nci_register_device(struct nci_dev *ndev)
+{
+	int rc;
+	struct device *dev = &ndev->nfc_dev->dev;
+	char name[32];
+
+	rc = nfc_register_device(ndev->nfc_dev);
+	if (rc)
+		goto exit;
+
+	ndev->flags = 0;
+
+	INIT_WORK(&ndev->cmd_work, nci_cmd_work);
+	snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev));
+	ndev->cmd_wq = create_singlethread_workqueue(name);
+	if (!ndev->cmd_wq) {
+		rc = -ENOMEM;
+		goto unreg_exit;
+	}
+
+	INIT_WORK(&ndev->rx_work, nci_rx_work);
+	snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev));
+	ndev->rx_wq = create_singlethread_workqueue(name);
+	if (!ndev->rx_wq) {
+		rc = -ENOMEM;
+		goto destroy_cmd_wq_exit;
+	}
+
+	INIT_WORK(&ndev->tx_work, nci_tx_work);
+	snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev));
+	ndev->tx_wq = create_singlethread_workqueue(name);
+	if (!ndev->tx_wq) {
+		rc = -ENOMEM;
+		goto destroy_rx_wq_exit;
+	}
+
+	skb_queue_head_init(&ndev->cmd_q);
+	skb_queue_head_init(&ndev->rx_q);
+	skb_queue_head_init(&ndev->tx_q);
+
+	setup_timer(&ndev->cmd_timer, nci_cmd_timer,
+		    (unsigned long) ndev);
+	setup_timer(&ndev->data_timer, nci_data_timer,
+		    (unsigned long) ndev);
+
+	mutex_init(&ndev->req_lock);
+
+	goto exit;
+
+destroy_rx_wq_exit:
+	destroy_workqueue(ndev->rx_wq);
+
+destroy_cmd_wq_exit:
+	destroy_workqueue(ndev->cmd_wq);
+
+unreg_exit:
+	nfc_unregister_device(ndev->nfc_dev);
+
+exit:
+	return rc;
+}
+EXPORT_SYMBOL(nci_register_device);
+
+/**
+ * nci_unregister_device - unregister a nci device in the nfc subsystem
+ *
+ * @dev: The nci device to unregister
+ */
+void nci_unregister_device(struct nci_dev *ndev)
+{
+	nci_close_device(ndev);
+
+	destroy_workqueue(ndev->cmd_wq);
+	destroy_workqueue(ndev->rx_wq);
+	destroy_workqueue(ndev->tx_wq);
+
+	nfc_unregister_device(ndev->nfc_dev);
+}
+EXPORT_SYMBOL(nci_unregister_device);
+
+/**
+ * nci_recv_frame - receive frame from NCI drivers
+ *
+ * @skb: The sk_buff to receive
+ */
+int nci_recv_frame(struct sk_buff *skb)
+{
+	struct nci_dev *ndev = (struct nci_dev *) skb->dev;
+
+	pr_debug("len %d\n", skb->len);
+
+	if (!ndev || (!test_bit(NCI_UP, &ndev->flags)
+		      && !test_bit(NCI_INIT, &ndev->flags))) {
+		kfree_skb(skb);
+		return -ENXIO;
+	}
+
+	/* Queue frame for rx worker thread */
+	skb_queue_tail(&ndev->rx_q, skb);
+	queue_work(ndev->rx_wq, &ndev->rx_work);
+
+	return 0;
+}
+EXPORT_SYMBOL(nci_recv_frame);
+
+static int nci_send_frame(struct sk_buff *skb)
+{
+	struct nci_dev *ndev = (struct nci_dev *) skb->dev;
+
+	pr_debug("len %d\n", skb->len);
+
+	if (!ndev) {
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	/* Get rid of skb owner, prior to sending to the driver. */
+	skb_orphan(skb);
+
+	return ndev->ops->send(skb);
+}
+
+/* Send NCI command */
+int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
+{
+	struct nci_ctrl_hdr *hdr;
+	struct sk_buff *skb;
+
+	pr_debug("opcode 0x%x, plen %d\n", opcode, plen);
+
+	skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
+	if (!skb) {
+		pr_err("no memory for command\n");
+		return -ENOMEM;
+	}
+
+	hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE);
+	hdr->gid = nci_opcode_gid(opcode);
+	hdr->oid = nci_opcode_oid(opcode);
+	hdr->plen = plen;
+
+	nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT);
+	nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
+
+	if (plen)
+		memcpy(skb_put(skb, plen), payload, plen);
+
+	skb->dev = (void *) ndev;
+
+	skb_queue_tail(&ndev->cmd_q, skb);
+	queue_work(ndev->cmd_wq, &ndev->cmd_work);
+
+	return 0;
+}
+
+/* ---- NCI TX Data worker thread ---- */
+
+static void nci_tx_work(struct work_struct *work)
+{
+	struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work);
+	struct sk_buff *skb;
+
+	pr_debug("credits_cnt %d\n", atomic_read(&ndev->credits_cnt));
+
+	/* Send queued tx data */
+	while (atomic_read(&ndev->credits_cnt)) {
+		skb = skb_dequeue(&ndev->tx_q);
+		if (!skb)
+			return;
+
+		/* Check if data flow control is used */
+		if (atomic_read(&ndev->credits_cnt) !=
+		    NCI_DATA_FLOW_CONTROL_NOT_USED)
+			atomic_dec(&ndev->credits_cnt);
+
+		pr_debug("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d\n",
+			 nci_pbf(skb->data),
+			 nci_conn_id(skb->data),
+			 nci_plen(skb->data));
+
+		nci_send_frame(skb);
+
+		mod_timer(&ndev->data_timer,
+			  jiffies + msecs_to_jiffies(NCI_DATA_TIMEOUT));
+	}
+}
+
+/* ----- NCI RX worker thread (data & control) ----- */
+
+static void nci_rx_work(struct work_struct *work)
+{
+	struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work);
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(&ndev->rx_q))) {
+		/* Process frame */
+		switch (nci_mt(skb->data)) {
+		case NCI_MT_RSP_PKT:
+			nci_rsp_packet(ndev, skb);
+			break;
+
+		case NCI_MT_NTF_PKT:
+			nci_ntf_packet(ndev, skb);
+			break;
+
+		case NCI_MT_DATA_PKT:
+			nci_rx_data_packet(ndev, skb);
+			break;
+
+		default:
+			pr_err("unknown MT 0x%x\n", nci_mt(skb->data));
+			kfree_skb(skb);
+			break;
+		}
+	}
+
+	/* check if a data exchange timout has occurred */
+	if (test_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags)) {
+		/* complete the data exchange transaction, if exists */
+		if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
+			nci_data_exchange_complete(ndev, NULL, -ETIMEDOUT);
+
+		clear_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
+	}
+}
+
+/* ----- NCI TX CMD worker thread ----- */
+
+static void nci_cmd_work(struct work_struct *work)
+{
+	struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work);
+	struct sk_buff *skb;
+
+	pr_debug("cmd_cnt %d\n", atomic_read(&ndev->cmd_cnt));
+
+	/* Send queued command */
+	if (atomic_read(&ndev->cmd_cnt)) {
+		skb = skb_dequeue(&ndev->cmd_q);
+		if (!skb)
+			return;
+
+		atomic_dec(&ndev->cmd_cnt);
+
+		pr_debug("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
+			 nci_pbf(skb->data),
+			 nci_opcode_gid(nci_opcode(skb->data)),
+			 nci_opcode_oid(nci_opcode(skb->data)),
+			 nci_plen(skb->data));
+
+		nci_send_frame(skb);
+
+		mod_timer(&ndev->cmd_timer,
+			  jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
+	}
+}