net/mac802154/main.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (C) 2007-2012 Siemens AG
0004  *
0005  * Written by:
0006  * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
0007  */
0008
0009 #include <linux/kernel.h>
0010 #include <linux/module.h>
0011 #include <linux/netdevice.h>
0012
0013 #include <net/netlink.h>
0014 #include <net/nl802154.h>
0015 #include <net/mac802154.h>
0016 #include <net/ieee802154_netdev.h>
0017 #include <net/route.h>
0018 #include <net/cfg802154.h>
0019
0020 #include "ieee802154_i.h"
0021 #include "cfg.h"
0022
0023 static void ieee802154_tasklet_handler(struct tasklet_struct *t)
0024 {
0025     struct ieee802154_local *local = from_tasklet(local, t, tasklet);
0026     struct sk_buff *skb;
0027
0028     while ((skb = skb_dequeue(&local->skb_queue))) {
0029         switch (skb->pkt_type) {
0030         case IEEE802154_RX_MSG:
0031             /* Clear skb->pkt_type in order to not confuse kernel
0032              * netstack.
0033              */
0034             skb->pkt_type = 0;
0035             ieee802154_rx(local, skb);
0036             break;
0037         default:
0038             WARN(1, "mac802154: Packet is of unknown type %d\n",
0039                  skb->pkt_type);
0040             kfree_skb(skb);
0041             break;
0042         }
0043     }
0044 }
0045
0046 struct ieee802154_hw *
0047 ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
0048 {
0049     struct wpan_phy *phy;
0050     struct ieee802154_local *local;
0051     size_t priv_size;
0052
0053     if (WARN_ON(!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
0054             !ops->start || !ops->stop || !ops->set_channel))
0055         return NULL;
0056
0057     /* Ensure 32-byte alignment of our private data and hw private data.
0058      * We use the wpan_phy priv data for both our ieee802154_local and for
0059      * the driver's private data
0060      *
0061      * in memory it'll be like this:
0062      *
0063      * +-------------------------+
0064      * | struct wpan_phy         |
0065      * +-------------------------+
0066      * | struct ieee802154_local |
0067      * +-------------------------+
0068      * | driver's private data   |
0069      * +-------------------------+
0070      *
0071      * Due to ieee802154 layer isn't aware of driver and MAC structures,
0072      * so lets align them here.
0073      */
0074
0075     priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
0076
0077     phy = wpan_phy_new(&mac802154_config_ops, priv_size);
0078     if (!phy) {
0079         pr_err("failure to allocate master IEEE802.15.4 device\n");
0080         return NULL;
0081     }
0082
0083     phy->privid = mac802154_wpan_phy_privid;
0084
0085     local = wpan_phy_priv(phy);
0086     local->phy = phy;
0087     local->hw.phy = local->phy;
0088     local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
0089     local->ops = ops;
0090
0091     INIT_LIST_HEAD(&local->interfaces);
0092     mutex_init(&local->iflist_mtx);
0093
0094     tasklet_setup(&local->tasklet, ieee802154_tasklet_handler);
0095
0096     skb_queue_head_init(&local->skb_queue);
0097
0098     INIT_WORK(&local->tx_work, ieee802154_xmit_worker);
0099
0100     /* init supported flags with 802.15.4 default ranges */
0101     phy->supported.max_minbe = 8;
0102     phy->supported.min_maxbe = 3;
0103     phy->supported.max_maxbe = 8;
0104     phy->supported.min_frame_retries = 0;
0105     phy->supported.max_frame_retries = 7;
0106     phy->supported.max_csma_backoffs = 5;
0107     phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
0108
0109     /* always supported */
0110     phy->supported.iftypes = BIT(NL802154_IFTYPE_NODE);
0111
0112     return &local->hw;
0113 }
0114 EXPORT_SYMBOL(ieee802154_alloc_hw);
0115
0116 void ieee802154_configure_durations(struct wpan_phy *phy)
0117 {
0118     u32 duration = 0;
0119
0120     switch (phy->current_page) {
0121     case 0:
0122         if (BIT(phy->current_channel) & 0x1)
0123             /* 868 MHz BPSK 802.15.4-2003: 20 ksym/s */
0124             duration = 50 * NSEC_PER_USEC;
0125         else if (BIT(phy->current_channel) & 0x7FE)
0126             /* 915 MHz BPSK 802.15.4-2003: 40 ksym/s */
0127             duration = 25 * NSEC_PER_USEC;
0128         else if (BIT(phy->current_channel) & 0x7FFF800)
0129             /* 2400 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
0130             duration = 16 * NSEC_PER_USEC;
0131         break;
0132     case 2:
0133         if (BIT(phy->current_channel) & 0x1)
0134             /* 868 MHz O-QPSK 802.15.4-2006: 25 ksym/s */
0135             duration = 40 * NSEC_PER_USEC;
0136         else if (BIT(phy->current_channel) & 0x7FE)
0137             /* 915 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
0138             duration = 16 * NSEC_PER_USEC;
0139         break;
0140     case 3:
0141         if (BIT(phy->current_channel) & 0x3FFF)
0142             /* 2.4 GHz CSS 802.15.4a-2007: 1/6 Msym/s */
0143             duration = 6 * NSEC_PER_USEC;
0144         break;
0145     default:
0146         break;
0147     }
0148
0149     if (!duration) {
0150         pr_debug("Unknown PHY symbol duration\n");
0151         return;
0152     }
0153
0154     phy->symbol_duration = duration;
0155     phy->lifs_period = (IEEE802154_LIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
0156     phy->sifs_period = (IEEE802154_SIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
0157 }
0158 EXPORT_SYMBOL(ieee802154_configure_durations);
0159
0160 void ieee802154_free_hw(struct ieee802154_hw *hw)
0161 {
0162     struct ieee802154_local *local = hw_to_local(hw);
0163
0164     BUG_ON(!list_empty(&local->interfaces));
0165
0166     mutex_destroy(&local->iflist_mtx);
0167
0168     wpan_phy_free(local->phy);
0169 }
0170 EXPORT_SYMBOL(ieee802154_free_hw);
0171
0172 static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
0173 {
0174     /* TODO warn on empty symbol_duration
0175      * Should be done when all drivers sets this value.
0176      */
0177
0178     wpan_phy->lifs_period =
0179         (IEEE802154_LIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
0180     wpan_phy->sifs_period =
0181         (IEEE802154_SIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
0182 }
0183
0184 int ieee802154_register_hw(struct ieee802154_hw *hw)
0185 {
0186     struct ieee802154_local *local = hw_to_local(hw);
0187     struct net_device *dev;
0188     int rc = -ENOSYS;
0189
0190     local->workqueue =
0191         create_singlethread_workqueue(wpan_phy_name(local->phy));
0192     if (!local->workqueue) {
0193         rc = -ENOMEM;
0194         goto out;
0195     }
0196
0197     hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
0198     local->ifs_timer.function = ieee802154_xmit_ifs_timer;
0199
0200     wpan_phy_set_dev(local->phy, local->hw.parent);
0201
0202     ieee802154_setup_wpan_phy_pib(local->phy);
0203
0204     ieee802154_configure_durations(local->phy);
0205
0206     if (!(hw->flags & IEEE802154_HW_CSMA_PARAMS)) {
0207         local->phy->supported.min_csma_backoffs = 4;
0208         local->phy->supported.max_csma_backoffs = 4;
0209         local->phy->supported.min_maxbe = 5;
0210         local->phy->supported.max_maxbe = 5;
0211         local->phy->supported.min_minbe = 3;
0212         local->phy->supported.max_minbe = 3;
0213     }
0214
0215     if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
0216         local->phy->supported.min_frame_retries = 3;
0217         local->phy->supported.max_frame_retries = 3;
0218     }
0219
0220     if (hw->flags & IEEE802154_HW_PROMISCUOUS)
0221         local->phy->supported.iftypes |= BIT(NL802154_IFTYPE_MONITOR);
0222
0223     rc = wpan_phy_register(local->phy);
0224     if (rc < 0)
0225         goto out_wq;
0226
0227     rtnl_lock();
0228
0229     dev = ieee802154_if_add(local, "wpan%d", NET_NAME_ENUM,
0230                 NL802154_IFTYPE_NODE,
0231                 cpu_to_le64(0x0000000000000000ULL));
0232     if (IS_ERR(dev)) {
0233         rtnl_unlock();
0234         rc = PTR_ERR(dev);
0235         goto out_phy;
0236     }
0237
0238     rtnl_unlock();
0239
0240     return 0;
0241
0242 out_phy:
0243     wpan_phy_unregister(local->phy);
0244 out_wq:
0245     destroy_workqueue(local->workqueue);
0246 out:
0247     return rc;
0248 }
0249 EXPORT_SYMBOL(ieee802154_register_hw);
0250
0251 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
0252 {
0253     struct ieee802154_local *local = hw_to_local(hw);
0254
0255     tasklet_kill(&local->tasklet);
0256     flush_workqueue(local->workqueue);
0257
0258     rtnl_lock();
0259
0260     ieee802154_remove_interfaces(local);
0261
0262     rtnl_unlock();
0263
0264     destroy_workqueue(local->workqueue);
0265     wpan_phy_unregister(local->phy);
0266 }
0267 EXPORT_SYMBOL(ieee802154_unregister_hw);
0268
0269 static int __init ieee802154_init(void)
0270 {
0271     return ieee802154_iface_init();
0272 }
0273
0274 static void __exit ieee802154_exit(void)
0275 {
0276     ieee802154_iface_exit();
0277
0278     rcu_barrier();
0279 }
0280
0281 subsys_initcall(ieee802154_init);
0282 module_exit(ieee802154_exit);
0283
0284 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
0285 MODULE_LICENSE("GPL v2");