// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2011 Instituto Nokia de Tecnologia
*
* Authors:
* Lauro Ramos Venancio <[email protected]>
* Aloisio Almeida Jr <[email protected]>
*/
#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);
}
const 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 <[email protected]>");
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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