From 7eda8b8e967781cfa5a04962502f9aa428f67e5f Mon Sep 17 00:00:00 2001 From: Samuel Ortiz Date: Mon, 22 Oct 2012 15:57:58 +0200 Subject: [PATCH] NFC: Use IDR library to assing NFC devices IDs As a consequence the NFC device IDs won't be increasing all the time, as IDR provides the first available ID. Signed-off-by: Samuel Ortiz --- include/net/nfc/nfc.h | 2 +- net/nfc/core.c | 23 ++++++++++++++++------- 2 files changed, 17 insertions(+), 8 deletions(-) diff --git a/include/net/nfc/nfc.h b/include/net/nfc/nfc.h index f05b106..fce80b2 100644 --- a/include/net/nfc/nfc.h +++ b/include/net/nfc/nfc.h @@ -95,7 +95,7 @@ struct nfc_genl_data { }; struct nfc_dev { - unsigned int idx; + int idx; u32 target_next_idx; struct nfc_target *targets; int n_targets; diff --git a/net/nfc/core.c b/net/nfc/core.c index f1c33f2..e94363d 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); -- 2.7.4