/* * The NFC Controller Interface is the communication protocol between an * NFC Controller (NFCC) and a Device Host (DH). * * Copyright (C) 2011 Texas Instruments, Inc. * * Written by Ilan Elias <ilane@ti.com> * * Acknowledgements: * This file is based on hci_core.c, which was written * by Maxim Krasnyansky. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ #include <linux/types.h> #include <linux/workqueue.h> #include <linux/completion.h> #include <linux/export.h> #include <linux/sched.h> #include <linux/bitops.h> #include <linux/skbuff.h> #include "../nfc.h" #include <net/nfc/nci.h> #include <net/nfc/nci_core.h> #include <linux/nfc.h> static void nci_cmd_work(struct work_struct *work); static void nci_rx_work(struct work_struct *work); static void nci_tx_work(struct work_struct *work); /* ---- NCI requests ---- */ void nci_req_complete(struct nci_dev *ndev, int result) { if (ndev->req_status == NCI_REQ_PEND) { ndev->req_result = result; ndev->req_status = NCI_REQ_DONE; complete(&ndev->req_completion); } } static void nci_req_cancel(struct nci_dev *ndev, int err) { if (ndev->req_status == NCI_REQ_PEND) { ndev->req_result = err; ndev->req_status = NCI_REQ_CANCELED; complete(&ndev->req_completion); } } /* Execute request and wait for completion. */ static int __nci_request(struct nci_dev *ndev, void (*req)(struct nci_dev *ndev, unsigned long opt), unsigned long opt, __u32 timeout) { int rc = 0; long completion_rc; ndev->req_status = NCI_REQ_PEND; init_completion(&ndev->req_completion); req(ndev, opt); completion_rc = wait_for_completion_interruptible_timeout( &ndev->req_completion, timeout); pr_debug("wait_for_completion return %ld\n", completion_rc); if (completion_rc > 0) { switch (ndev->req_status) { case NCI_REQ_DONE: rc = nci_to_errno(ndev->req_result); break; case NCI_REQ_CANCELED: rc = -ndev->req_result; break; default: rc = -ETIMEDOUT; break; } } else { pr_err("wait_for_completion_interruptible_timeout failed %ld\n", completion_rc); rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc)); } ndev->req_status = ndev->req_result = 0; return rc; } static inline int nci_request(struct nci_dev *ndev, void (*req)(struct nci_dev *ndev, unsigned long opt), unsigned long opt, __u32 timeout) { int rc; if (!test_bit(NCI_UP, &ndev->flags)) return -ENETDOWN; /* Serialize all requests */ mutex_lock(&ndev->req_lock); rc = __nci_request(ndev, req, opt, timeout); mutex_unlock(&ndev->req_lock); return rc; } static void nci_reset_req(struct nci_dev *ndev, unsigned long opt) { struct nci_core_reset_cmd cmd; cmd.reset_type = NCI_RESET_TYPE_RESET_CONFIG; nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 1, &cmd); } static void nci_init_req(struct nci_dev *ndev, unsigned long opt) { nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL); } static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt) { struct nci_rf_disc_map_cmd cmd; struct disc_map_config *cfg = cmd.mapping_configs; __u8 *num = &cmd.num_mapping_configs; int i; /* set rf mapping configurations */ *num = 0; /* by default mapping is set to NCI_RF_INTERFACE_FRAME */ for (i = 0; i < ndev->num_supported_rf_interfaces; i++) { if (ndev->supported_rf_interfaces[i] == NCI_RF_INTERFACE_ISO_DEP) { cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP; cfg[*num].mode = NCI_DISC_MAP_MODE_POLL | NCI_DISC_MAP_MODE_LISTEN; cfg[*num].rf_interface = NCI_RF_INTERFACE_ISO_DEP; (*num)++; } else if (ndev->supported_rf_interfaces[i] == NCI_RF_INTERFACE_NFC_DEP) { cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP; cfg[*num].mode = NCI_DISC_MAP_MODE_POLL | NCI_DISC_MAP_MODE_LISTEN; cfg[*num].rf_interface = NCI_RF_INTERFACE_NFC_DEP; (*num)++; } if (*num == NCI_MAX_NUM_MAPPING_CONFIGS) break; } nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD, (1 + ((*num)*sizeof(struct disc_map_config))), &cmd); } static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt) { struct nci_rf_disc_cmd cmd; __u32 protocols = opt; cmd.num_disc_configs = 0; if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) && (protocols & NFC_PROTO_JEWEL_MASK || protocols & NFC_PROTO_MIFARE_MASK || protocols & NFC_PROTO_ISO14443_MASK || protocols & NFC_PROTO_NFC_DEP_MASK)) { cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode = NCI_NFC_A_PASSIVE_POLL_MODE; cmd.disc_configs[cmd.num_disc_configs].frequency = 1; cmd.num_disc_configs++; } if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) && (protocols & NFC_PROTO_ISO14443_MASK)) { cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode = NCI_NFC_B_PASSIVE_POLL_MODE; cmd.disc_configs[cmd.num_disc_configs].frequency = 1; cmd.num_disc_configs++; } if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) && (protocols & NFC_PROTO_FELICA_MASK || protocols & NFC_PROTO_NFC_DEP_MASK)) { cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode = NCI_NFC_F_PASSIVE_POLL_MODE; cmd.disc_configs[cmd.num_disc_configs].frequency = 1; cmd.num_disc_configs++; } nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD, (1 + (cmd.num_disc_configs*sizeof(struct disc_config))), &cmd); } static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt) { struct nci_rf_deactivate_cmd cmd; cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE; nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD, sizeof(struct nci_rf_deactivate_cmd), &cmd); } static int nci_open_device(struct nci_dev *ndev) { int rc = 0; mutex_lock(&ndev->req_lock); if (test_bit(NCI_UP, &ndev->flags)) { rc = -EALREADY; goto done; } if (ndev->ops->open(ndev)) { rc = -EIO; goto done; } atomic_set(&ndev->cmd_cnt, 1); set_bit(NCI_INIT, &ndev->flags); rc = __nci_request(ndev, nci_reset_req, 0, msecs_to_jiffies(NCI_RESET_TIMEOUT)); if (!rc) { rc = __nci_request(ndev, nci_init_req, 0, msecs_to_jiffies(NCI_INIT_TIMEOUT)); } if (!rc) { rc = __nci_request(ndev, nci_init_complete_req, 0, msecs_to_jiffies(NCI_INIT_TIMEOUT)); } clear_bit(NCI_INIT, &ndev->flags); if (!rc) { set_bit(NCI_UP, &ndev->flags); } else { /* Init failed, cleanup */ skb_queue_purge(&ndev->cmd_q); skb_queue_purge(&ndev->rx_q); skb_queue_purge(&ndev->tx_q); ndev->ops->close(ndev); ndev->flags = 0; } done: mutex_unlock(&ndev->req_lock); return rc; } static int nci_close_device(struct nci_dev *ndev) { nci_req_cancel(ndev, ENODEV); mutex_lock(&ndev->req_lock); if (!test_and_clear_bit(NCI_UP, &ndev->flags)) { del_timer_sync(&ndev->cmd_timer); mutex_unlock(&ndev->req_lock); return 0; } /* Drop RX and TX queues */ skb_queue_purge(&ndev->rx_q); skb_queue_purge(&ndev->tx_q); /* Flush RX and TX wq */ flush_workqueue(ndev->rx_wq); flush_workqueue(ndev->tx_wq); /* Reset device */ skb_queue_purge(&ndev->cmd_q); atomic_set(&ndev->cmd_cnt, 1); set_bit(NCI_INIT, &ndev->flags); __nci_request(ndev, nci_reset_req, 0, msecs_to_jiffies(NCI_RESET_TIMEOUT)); clear_bit(NCI_INIT, &ndev->flags); /* Flush cmd wq */ flush_workqueue(ndev->cmd_wq); /* After this point our queues are empty * and no works are scheduled. */ ndev->ops->close(ndev); /* Clear flags */ ndev->flags = 0; mutex_unlock(&ndev->req_lock); return 0; } /* NCI command timer function */ static void nci_cmd_timer(unsigned long arg) { struct nci_dev *ndev = (void *) arg; atomic_set(&ndev->cmd_cnt, 1); queue_work(ndev->cmd_wq, &ndev->cmd_work); } static int nci_dev_up(struct nfc_dev *nfc_dev) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); return nci_open_device(ndev); } static int nci_dev_down(struct nfc_dev *nfc_dev) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); return nci_close_device(ndev); } static int nci_start_poll(struct nfc_dev *nfc_dev, __u32 protocols) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); int rc; if (test_bit(NCI_DISCOVERY, &ndev->flags)) { pr_err("unable to start poll, since poll is already active\n"); return -EBUSY; } if (ndev->target_active_prot) { pr_err("there is an active target\n"); return -EBUSY; } if (test_bit(NCI_POLL_ACTIVE, &ndev->flags)) { pr_debug("target is active, implicitly deactivate...\n"); rc = nci_request(ndev, nci_rf_deactivate_req, 0, msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT)); if (rc) return -EBUSY; } rc = nci_request(ndev, nci_rf_discover_req, protocols, msecs_to_jiffies(NCI_RF_DISC_TIMEOUT)); if (!rc) ndev->poll_prots = protocols; return rc; } static void nci_stop_poll(struct nfc_dev *nfc_dev) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); if (!test_bit(NCI_DISCOVERY, &ndev->flags)) { pr_err("unable to stop poll, since poll is not active\n"); return; } nci_request(ndev, nci_rf_deactivate_req, 0, msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT)); } static int nci_activate_target(struct nfc_dev *nfc_dev, __u32 target_idx, __u32 protocol) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); pr_debug("target_idx %d, protocol 0x%x\n", target_idx, protocol); if (!test_bit(NCI_POLL_ACTIVE, &ndev->flags)) { pr_err("there is no available target to activate\n"); return -EINVAL; } if (ndev->target_active_prot) { pr_err("there is already an active target\n"); return -EBUSY; } if (!(ndev->target_available_prots & (1 << protocol))) { pr_err("target does not support the requested protocol 0x%x\n", protocol); return -EINVAL; } ndev->target_active_prot = protocol; ndev->target_available_prots = 0; return 0; } static void nci_deactivate_target(struct nfc_dev *nfc_dev, __u32 target_idx) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); pr_debug("target_idx %d\n", target_idx); if (!ndev->target_active_prot) { pr_err("unable to deactivate target, no active target\n"); return; } ndev->target_active_prot = 0; if (test_bit(NCI_POLL_ACTIVE, &ndev->flags)) { nci_request(ndev, nci_rf_deactivate_req, 0, msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT)); } } static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx, struct sk_buff *skb, data_exchange_cb_t cb, void *cb_context) { struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); int rc; pr_debug("target_idx %d, len %d\n", target_idx, skb->len); if (!ndev->target_active_prot) { pr_err("unable to exchange data, no active target\n"); return -EINVAL; } if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags)) return -EBUSY; /* store cb and context to be used on receiving data */ ndev->data_exchange_cb = cb; ndev->data_exchange_cb_context = cb_context; rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb); if (rc) clear_bit(NCI_DATA_EXCHANGE, &ndev->flags); return rc; } static struct nfc_ops nci_nfc_ops = { .dev_up = nci_dev_up, .dev_down = nci_dev_down, .start_poll = nci_start_poll, .stop_poll = nci_stop_poll, .activate_target = nci_activate_target, .deactivate_target = nci_deactivate_target, .data_exchange = nci_data_exchange, }; /* ---- Interface to NCI drivers ---- */ /** * nci_allocate_device - allocate a new nci device * * @ops: device operations * @supported_protocols: NFC protocols supported by the device */ struct nci_dev *nci_allocate_device(struct nci_ops *ops, __u32 supported_protocols, int tx_headroom, int tx_tailroom) { struct nci_dev *ndev; pr_debug("supported_protocols 0x%x\n", supported_protocols); if (!ops->open || !ops->close || !ops->send) return NULL; if (!supported_protocols) return NULL; ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL); if (!ndev) return NULL; ndev->ops = ops; ndev->tx_headroom = tx_headroom; ndev->tx_tailroom = tx_tailroom; ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops, supported_protocols, tx_headroom + NCI_DATA_HDR_SIZE, tx_tailroom); if (!ndev->nfc_dev) goto free_exit; nfc_set_drvdata(ndev->nfc_dev, ndev); return ndev; free_exit: kfree(ndev); return NULL; } EXPORT_SYMBOL(nci_allocate_device); /** * nci_free_device - deallocate nci device * * @ndev: The nci device to deallocate */ void nci_free_device(struct nci_dev *ndev) { nfc_free_device(ndev->nfc_dev); kfree(ndev); } EXPORT_SYMBOL(nci_free_device); /** * nci_register_device - register a nci device in the nfc subsystem * * @dev: The nci device to register */ int nci_register_device(struct nci_dev *ndev) { int rc; struct device *dev = &ndev->nfc_dev->dev; char name[32]; rc = nfc_register_device(ndev->nfc_dev); if (rc) goto exit; ndev->flags = 0; INIT_WORK(&ndev->cmd_work, nci_cmd_work); snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev)); ndev->cmd_wq = create_singlethread_workqueue(name); if (!ndev->cmd_wq) { rc = -ENOMEM; goto unreg_exit; } INIT_WORK(&ndev->rx_work, nci_rx_work); snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev)); ndev->rx_wq = create_singlethread_workqueue(name); if (!ndev->rx_wq) { rc = -ENOMEM; goto destroy_cmd_wq_exit; } INIT_WORK(&ndev->tx_work, nci_tx_work); snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev)); ndev->tx_wq = create_singlethread_workqueue(name); if (!ndev->tx_wq) { rc = -ENOMEM; goto destroy_rx_wq_exit; } skb_queue_head_init(&ndev->cmd_q); skb_queue_head_init(&ndev->rx_q); skb_queue_head_init(&ndev->tx_q); setup_timer(&ndev->cmd_timer, nci_cmd_timer, (unsigned long) ndev); mutex_init(&ndev->req_lock); goto exit; destroy_rx_wq_exit: destroy_workqueue(ndev->rx_wq); destroy_cmd_wq_exit: destroy_workqueue(ndev->cmd_wq); unreg_exit: nfc_unregister_device(ndev->nfc_dev); exit: return rc; } EXPORT_SYMBOL(nci_register_device); /** * nci_unregister_device - unregister a nci device in the nfc subsystem * * @dev: The nci device to unregister */ void nci_unregister_device(struct nci_dev *ndev) { nci_close_device(ndev); destroy_workqueue(ndev->cmd_wq); destroy_workqueue(ndev->rx_wq); destroy_workqueue(ndev->tx_wq); nfc_unregister_device(ndev->nfc_dev); } EXPORT_SYMBOL(nci_unregister_device); /** * nci_recv_frame - receive frame from NCI drivers * * @skb: The sk_buff to receive */ int nci_recv_frame(struct sk_buff *skb) { struct nci_dev *ndev = (struct nci_dev *) skb->dev; pr_debug("len %d\n", skb->len); if (!ndev || (!test_bit(NCI_UP, &ndev->flags) && !test_bit(NCI_INIT, &ndev->flags))) { kfree_skb(skb); return -ENXIO; } /* Queue frame for rx worker thread */ skb_queue_tail(&ndev->rx_q, skb); queue_work(ndev->rx_wq, &ndev->rx_work); return 0; } EXPORT_SYMBOL(nci_recv_frame); static int nci_send_frame(struct sk_buff *skb) { struct nci_dev *ndev = (struct nci_dev *) skb->dev; pr_debug("len %d\n", skb->len); if (!ndev) { kfree_skb(skb); return -ENODEV; } /* Get rid of skb owner, prior to sending to the driver. */ skb_orphan(skb); return ndev->ops->send(skb); } /* Send NCI command */ int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload) { struct nci_ctrl_hdr *hdr; struct sk_buff *skb; pr_debug("opcode 0x%x, plen %d\n", opcode, plen); skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL); if (!skb) { pr_err("no memory for command\n"); return -ENOMEM; } hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE); hdr->gid = nci_opcode_gid(opcode); hdr->oid = nci_opcode_oid(opcode); hdr->plen = plen; nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT); nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST); if (plen) memcpy(skb_put(skb, plen), payload, plen); skb->dev = (void *) ndev; skb_queue_tail(&ndev->cmd_q, skb); queue_work(ndev->cmd_wq, &ndev->cmd_work); return 0; } /* ---- NCI TX Data worker thread ---- */ static void nci_tx_work(struct work_struct *work) { struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work); struct sk_buff *skb; pr_debug("credits_cnt %d\n", atomic_read(&ndev->credits_cnt)); /* Send queued tx data */ while (atomic_read(&ndev->credits_cnt)) { skb = skb_dequeue(&ndev->tx_q); if (!skb) return; /* Check if data flow control is used */ if (atomic_read(&ndev->credits_cnt) != NCI_DATA_FLOW_CONTROL_NOT_USED) atomic_dec(&ndev->credits_cnt); pr_debug("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d\n", nci_pbf(skb->data), nci_conn_id(skb->data), nci_plen(skb->data)); nci_send_frame(skb); } } /* ----- NCI RX worker thread (data & control) ----- */ static void nci_rx_work(struct work_struct *work) { struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work); struct sk_buff *skb; while ((skb = skb_dequeue(&ndev->rx_q))) { /* Process frame */ switch (nci_mt(skb->data)) { case NCI_MT_RSP_PKT: nci_rsp_packet(ndev, skb); break; case NCI_MT_NTF_PKT: nci_ntf_packet(ndev, skb); break; case NCI_MT_DATA_PKT: nci_rx_data_packet(ndev, skb); break; default: pr_err("unknown MT 0x%x\n", nci_mt(skb->data)); kfree_skb(skb); break; } } } /* ----- NCI TX CMD worker thread ----- */ static void nci_cmd_work(struct work_struct *work) { struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work); struct sk_buff *skb; pr_debug("cmd_cnt %d\n", atomic_read(&ndev->cmd_cnt)); /* Send queued command */ if (atomic_read(&ndev->cmd_cnt)) { skb = skb_dequeue(&ndev->cmd_q); if (!skb) return; atomic_dec(&ndev->cmd_cnt); pr_debug("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n", nci_pbf(skb->data), nci_opcode_gid(nci_opcode(skb->data)), nci_opcode_oid(nci_opcode(skb->data)), nci_plen(skb->data)); nci_send_frame(skb); mod_timer(&ndev->cmd_timer, jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT)); } }