aboutsummaryrefslogtreecommitdiff
path: root/net/nfc/core.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/nfc/core.c')
-rw-r--r--net/nfc/core.c468
1 files changed, 468 insertions, 0 deletions
diff --git a/net/nfc/core.c b/net/nfc/core.c
new file mode 100644
index 00000000000..b6fd4e1f205
--- /dev/null
+++ b/net/nfc/core.c
@@ -0,0 +1,468 @@
+/*
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "nfc.h"
+
+#define VERSION "0.1"
+
+int nfc_devlist_generation;
+DEFINE_MUTEX(nfc_devlist_mutex);
+
+int nfc_printk(const char *level, const char *format, ...)
+{
+ struct va_format vaf;
+ va_list args;
+ int r;
+
+ va_start(args, format);
+
+ vaf.fmt = format;
+ vaf.va = &args;
+
+ r = printk("%sNFC: %pV\n", level, &vaf);
+
+ va_end(args);
+
+ return r;
+}
+EXPORT_SYMBOL(nfc_printk);
+
+/**
+ * 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;
+
+ nfc_dbg("dev_name=%s protocols=0x%x", 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;
+
+ nfc_dbg("dev_name=%s", 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;
+
+ nfc_dbg("dev_name=%s target_idx=%u protocol=%u", 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);
+
+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;
+
+ nfc_dbg("dev_name=%s target_idx=%u", 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);
+
+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;
+
+ nfc_dbg("dev_name=%s target_idx=%u skb->len=%u", 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_skb - allocate a skb for data exchange responses
+ *
+ * @size: size to allocate
+ * @gfp: gfp flags
+ */
+struct sk_buff *nfc_alloc_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_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;
+
+ nfc_dbg("dev_name=%s n_targets=%d", 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);
+
+ nfc_dbg("dev_name=%s", 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)
+{
+ 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;
+
+ 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;
+
+ nfc_dbg("dev_name=%s", 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)
+ nfc_dbg("The userspace won't be notified that the device %s was"
+ " added", 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;
+
+ nfc_dbg("dev_name=%s", 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)
+ nfc_dbg("The userspace won't be notified that the device %s"
+ " was removed", dev_name(&dev->dev));
+
+}
+EXPORT_SYMBOL(nfc_unregister_device);
+
+static int __init nfc_init(void)
+{
+ int rc;
+
+ nfc_info("NFC Core ver %s", 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");