| /* |
| * 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; |
| } |
| |
| int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode) |
| { |
| int rc = 0; |
| u8 *gb; |
| size_t gb_len; |
| |
| 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; |
| } |
| |
| rc = dev->ops->dep_link_up(dev, target_index, comm_mode, gb, gb_len); |
| |
| 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; |
| } |
| |
| if (dev->dep_rf_mode == NFC_RF_TARGET) { |
| rc = -EOPNOTSUPP; |
| goto error; |
| } |
| |
| rc = dev->ops->dep_link_down(dev); |
| if (!rc) { |
| dev->dep_link_up = false; |
| 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; |
| dev->dep_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; |
| |
| 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; |
| } |
| |
| 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); |
| |
| if (gb_len > NFC_MAX_GT_LEN) |
| return -EINVAL; |
| |
| return nfc_llcp_set_remote_gb(dev, gb, gb_len); |
| } |
| EXPORT_SYMBOL(nfc_set_remote_general_bytes); |
| |
| /** |
| * 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); |
| |
| 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); |
| |
| spin_lock_bh(&dev->targets_lock); |
| |
| for (i = 0; i < dev->n_targets; i++) { |
| tg = &dev->targets[i]; |
| if (tg->idx == target_idx) |
| break; |
| } |
| |
| if (i == dev->n_targets) { |
| spin_unlock_bh(&dev->targets_lock); |
| return -EINVAL; |
| } |
| |
| dev->targets_generation++; |
| dev->n_targets--; |
| |
| 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; |
| } |
| |
| spin_unlock_bh(&dev->targets_lock); |
| |
| nfc_genl_target_lost(dev, target_idx); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(nfc_target_lost); |
| |
| 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_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)); |
| |
| 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); |
| |
| nfc_llcp_unregister_device(dev); |
| |
| 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 = 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"); |