diff options
Diffstat (limited to 'net/nfc/core.c')
| -rw-r--r-- | net/nfc/core.c | 1247 |
1 files changed, 1247 insertions, 0 deletions
diff --git a/net/nfc/core.c b/net/nfc/core.c new file mode 100644 index 000000000..eb2c0959e --- /dev/null +++ b/net/nfc/core.c @@ -0,0 +1,1247 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2011 Instituto Nokia de Tecnologia + * + * Authors: + * Lauro Ramos Venancio <lauro.venancio@openbossa.org> + * Aloisio Almeida Jr <aloisio.almeida@openbossa.org> + */ + +#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 (dev->shutting_down) { + 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->shutting_down) { + rc = -ENODEV; + goto error; + } + + if (dev->rfkill && rfkill_blocked(dev->rfkill)) { + rc = -ERFKILL; + 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 (dev->shutting_down) { + 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 + * @im_protocols: bitset of nfc initiator protocols to be used for polling + * @tm_protocols: bitset of nfc transport protocols to 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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 + * @mode: idle or sleep? + */ +int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx, u8 mode) +{ + int rc = 0; + + pr_debug("dev_name=%s target_idx=%u\n", + dev_name(&dev->dev), target_idx); + + device_lock(&dev->dev); + + if (dev->shutting_down) { + 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, mode); + 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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 (dev->shutting_down) { + 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, const 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, + const 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 + * + * @dev: device sending the response + * @sk: socket sending the response + * @flags: MSG_DONTWAIT flag + * @size: size to allocate + * @err: pointer to memory to store the error code + */ +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 + * @n_targets: 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) +{ + const 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); + +int nfc_se_connectivity(struct nfc_dev *dev, u8 se_idx) +{ + int rc; + + pr_debug("connectivity: %x\n", se_idx); + + device_lock(&dev->dev); + rc = nfc_genl_se_connectivity(dev, se_idx); + device_unlock(&dev->dev); + return rc; +} +EXPORT_SYMBOL(nfc_se_connectivity); + +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); + } + + ida_free(&nfc_index_ida, dev->idx); + + 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(struct timer_list *t) +{ + struct nfc_dev *dev = from_timer(dev, t, check_pres_timer); + + 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 + * @tx_headroom: reserved space at beginning of skb + * @tx_tailroom: reserved space at end of skb + */ +struct nfc_dev *nfc_allocate_device(const struct nfc_ops *ops, + u32 supported_protocols, + int tx_headroom, int tx_tailroom) +{ + struct nfc_dev *dev; + int rc; + + 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; + + rc = ida_alloc(&nfc_index_ida, GFP_KERNEL); + if (rc < 0) + goto err_free_dev; + dev->idx = rc; + + dev->dev.class = &nfc_class; + 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; + 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) { + timer_setup(&dev->check_pres_timer, nfc_check_pres_timeout, 0); + INIT_WORK(&dev->check_pres_work, nfc_check_pres_work); + } + + return dev; + +err_free_dev: + kfree(dev); + + return NULL; +} +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"); + + device_lock(&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; + } + } + dev->shutting_down = false; + device_unlock(&dev->dev); + + 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)); + + 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)); + + device_lock(&dev->dev); + if (dev->rfkill) { + rfkill_unregister(dev->rfkill); + rfkill_destroy(dev->rfkill); + dev->rfkill = NULL; + } + dev->shutting_down = true; + device_unlock(&dev->dev); + + if (dev->ops->check_presence) { + del_timer_sync(&dev->check_pres_timer); + cancel_work_sync(&dev->check_pres_work); + } + + nfc_llcp_unregister_device(dev); + + mutex_lock(&nfc_devlist_mutex); + nfc_devlist_generation++; + device_del(&dev->dev); + mutex_unlock(&nfc_devlist_mutex); +} +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); 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