diff options
Diffstat (limited to 'net/nfc')
| -rw-r--r-- | net/nfc/core.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/net/nfc/core.c b/net/nfc/core.c index f1c33f233311..e94363dbbf4a 100644 --- a/net/nfc/core.c +++ b/net/nfc/core.c @@ -40,6 +40,9 @@ int nfc_devlist_generation; DEFINE_MUTEX(nfc_devlist_mutex); +/* NFC device ID bitmap */ +static DEFINE_IDA(nfc_index_ida); + /** * nfc_dev_up - turn on the NFC device * @@ -760,7 +763,6 @@ 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 || @@ -774,11 +776,6 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, 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; @@ -814,6 +811,14 @@ int nfc_register_device(struct nfc_dev *dev) pr_debug("dev_name=%s\n", dev_name(&dev->dev)); + dev->idx = ida_simple_get(&nfc_index_ida, 0, 0, GFP_KERNEL); + if (dev->idx < 0) + return dev->idx; + + dev->dev.class = &nfc_class; + dev_set_name(&dev->dev, "nfc%d", dev->idx); + device_initialize(&dev->dev); + mutex_lock(&nfc_devlist_mutex); nfc_devlist_generation++; rc = device_add(&dev->dev); @@ -842,10 +847,12 @@ EXPORT_SYMBOL(nfc_register_device); */ void nfc_unregister_device(struct nfc_dev *dev) { - int rc; + int rc, id; pr_debug("dev_name=%s\n", dev_name(&dev->dev)); + id = dev->idx; + mutex_lock(&nfc_devlist_mutex); nfc_devlist_generation++; @@ -864,6 +871,8 @@ void nfc_unregister_device(struct nfc_dev *dev) pr_debug("The userspace won't be notified that the device %s was removed\n", dev_name(&dev->dev)); + ida_simple_remove(&nfc_index_ida, id); + } EXPORT_SYMBOL(nfc_unregister_device); |