2011-08-16 17:36:30

by Elias, Ilan

[permalink] [raw]
Subject: [PATCH 3/4] NFC: Basic NFC NCI protocol implementation

The NFC Controller Interface (NCI) is a standard communication protocol between an NFC Controller (NFCC) and a Device Host (DH), defined by the NFC Forum.

Signed-off-by: Ilan Elias <[email protected]>
---
include/net/nfc/nci.h | 313 ++++++++++++++++++
include/net/nfc/nci_core.h | 177 +++++++++++
net/nfc/Kconfig | 2 +
net/nfc/Makefile | 1 +
net/nfc/nci/Kconfig | 10 +
net/nfc/nci/Makefile | 7 +
net/nfc/nci/nci_core.c | 750 ++++++++++++++++++++++++++++++++++++++++++++
net/nfc/nci/nci_data.c | 252 +++++++++++++++
net/nfc/nci/nci_lib.c | 94 ++++++
net/nfc/nci/nci_ntf.c | 264 ++++++++++++++++
net/nfc/nci/nci_rsp.c | 226 +++++++++++++
11 files changed, 2096 insertions(+), 0 deletions(-)
create mode 100644 include/net/nfc/nci.h
create mode 100644 include/net/nfc/nci_core.h
create mode 100644 net/nfc/nci/Kconfig
create mode 100644 net/nfc/nci/Makefile
create mode 100644 net/nfc/nci/nci_core.c
create mode 100644 net/nfc/nci/nci_data.c
create mode 100644 net/nfc/nci/nci_lib.c
create mode 100644 net/nfc/nci/nci_ntf.c
create mode 100644 net/nfc/nci/nci_rsp.c

diff --git a/include/net/nfc/nci.h b/include/net/nfc/nci.h
new file mode 100644
index 0000000..1c55e03
--- /dev/null
+++ b/include/net/nfc/nci.h
@@ -0,0 +1,313 @@
+/*
+ * 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 <[email protected]>
+ *
+ * Acknowledgements:
+ * This file is based on hci.h, 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
+ *
+ */
+
+#ifndef __NCI_H
+#define __NCI_H
+
+/* NCI constants */
+#define NCI_MAX_NUM_MAPPING_CONFIGS 10
+#define NCI_MAX_NUM_RF_CONFIGS 10
+#define NCI_MAX_NUM_CONN 10
+
+/* NCI Status Codes */
+#define NCI_STATUS_OK 0x00
+#define NCI_STATUS_REJECTED 0x01
+#define NCI_STATUS_MESSAGE_CORRUPTED 0x02
+#define NCI_STATUS_BUFFER_FULL 0x03
+#define NCI_STATUS_FAILED 0x04
+#define NCI_STATUS_NOT_INITIALIZED 0x05
+#define NCI_STATUS_SYNTAX_ERROR 0x06
+#define NCI_STATUS_SEMANTIC_ERROR 0x07
+#define NCI_STATUS_UNKNOWN_GID 0x08
+#define NCI_STATUS_UNKNOWN_OID 0x09
+#define NCI_STATUS_INVALID_PARAM 0x0a
+#define NCI_STATUS_MESSAGE_SIZE_EXCEEDED 0x0b
+/* Discovery Specific Status Codes */
+#define NCI_STATUS_DISCOVERY_ALREADY_STARTED 0xa0
+#define NCI_STATUS_DISCOVERY_TARGET_ACTIVATION_FAILED 0xa1
+/* RF Interface Specific Status Codes */
+#define NCI_STATUS_RF_TRANSMISSION_ERROR 0xb0
+#define NCI_STATUS_RF_PROTOCOL_ERROR 0xb1
+#define NCI_STATUS_RF_TIMEOUT_ERROR 0xb2
+#define NCI_STATUS_RF_LINK_LOSS_ERROR 0xb3
+/* NFCEE Interface Specific Status Codes */
+#define NCI_STATUS_MAX_ACTIVE_NFCEE_INTERFACES_REACHED 0xc0
+#define NCI_STATUS_NFCEE_INTERFACE_ACTIVATION_FAILED 0xc1
+#define NCI_STATUS_NFCEE_TRANSMISSION_ERROR 0xc2
+#define NCI_STATUS_NFCEE_PROTOCOL_ERROR 0xc3
+#define NCI_STATUS_NFCEE_TIMEOUT_ERROR 0xc4
+
+/* NCI RF Technology and Mode */
+#define NCI_NFC_A_PASSIVE_POLL_MODE 0x00
+#define NCI_NFC_B_PASSIVE_POLL_MODE 0x01
+#define NCI_NFC_F_PASSIVE_POLL_MODE 0x02
+#define NCI_NFC_A_ACTIVE_POLL_MODE 0x03
+#define NCI_NFC_F_ACTIVE_POLL_MODE 0x05
+#define NCI_NFC_A_PASSIVE_LISTEN_MODE 0x80
+#define NCI_NFC_B_PASSIVE_LISTEN_MODE 0x81
+#define NCI_NFC_F_PASSIVE_LISTEN_MODE 0x82
+#define NCI_NFC_A_ACTIVE_LISTEN_MODE 0x83
+#define NCI_NFC_F_ACTIVE_LISTEN_MODE 0x85
+
+/* NCI RF Protocols */
+#define NCI_RF_PROTOCOL_UNKNOWN 0x00
+#define NCI_RF_PROTOCOL_T1T 0x01
+#define NCI_RF_PROTOCOL_T2T 0x02
+#define NCI_RF_PROTOCOL_T3T 0x03
+#define NCI_RF_PROTOCOL_ISO_DEP 0x04
+#define NCI_RF_PROTOCOL_NFC_DEP 0x05
+
+/* NCI RF Interfaces */
+#define NCI_RF_INTERFACE_RFU 0x00
+#define NCI_RF_INTERFACE_FRAME 0x01
+#define NCI_RF_INTERFACE_ISO_DEP 0x02
+#define NCI_RF_INTERFACE_NFC_DEP 0x03
+
+/* NCI RF_DISCOVER_MAP_CMD modes */
+#define NCI_DISC_MAP_MODE_POLL 0x01
+#define NCI_DISC_MAP_MODE_LISTEN 0x02
+#define NCI_DISC_MAP_MODE_BOTH 0x03
+
+/* NCI Discovery Types */
+#define NCI_DISCOVERY_TYPE_POLL_A_PASSIVE 0x00
+#define NCI_DISCOVERY_TYPE_POLL_B_PASSIVE 0x01
+#define NCI_DISCOVERY_TYPE_POLL_F_PASSIVE 0x02
+#define NCI_DISCOVERY_TYPE_POLL_A_ACTIVE 0x03
+#define NCI_DISCOVERY_TYPE_POLL_F_ACTIVE 0x05
+#define NCI_DISCOVERY_TYPE_WAKEUP_A_PASSIVE 0x06
+#define NCI_DISCOVERY_TYPE_WAKEUP_B_PASSIVE 0x07
+#define NCI_DISCOVERY_TYPE_WAKEUP_A_ACTIVE 0x09
+#define NCI_DISCOVERY_TYPE_LISTEN_A_PASSIVE 0x80
+#define NCI_DISCOVERY_TYPE_LISTEN_B_PASSIVE 0x81
+#define NCI_DISCOVERY_TYPE_LISTEN_F_PASSIVE 0x82
+#define NCI_DISCOVERY_TYPE_LISTEN_A_ACTIVE 0x83
+#define NCI_DISCOVERY_TYPE_LISTEN_F_ACTIVE 0x85
+
+/* NCI Deactivation Type */
+#define NCI_DEACTIVATE_TYPE_IDLE_MODE 0x00
+#define NCI_DEACTIVATE_TYPE_SLEEP_MODE 0x01
+#define NCI_DEACTIVATE_TYPE_SLEEP_AF_MODE 0x02
+#define NCI_DEACTIVATE_TYPE_RF_LINK_LOSS 0x03
+#define NCI_DEACTIVATE_TYPE_DISCOVERY_ERROR 0x04
+
+/* Message Type (MT) */
+#define NCI_MT_DATA_PKT 0x00
+#define NCI_MT_CMD_PKT 0x01
+#define NCI_MT_RSP_PKT 0x02
+#define NCI_MT_NTF_PKT 0x03
+
+#define nci_mt(hdr) (((hdr)[0]>>5)&0x07)
+#define nci_mt_set(hdr, mt) ((hdr)[0] |= (__u8)(((mt)&0x07)<<5))
+
+/* Packet Boundary Flag (PBF) */
+#define NCI_PBF_LAST 0x00
+#define NCI_PBF_CONT 0x01
+
+#define nci_pbf(hdr) (__u8)(((hdr)[0]>>4)&0x01)
+#define nci_pbf_set(hdr, pbf) ((hdr)[0] |= (__u8)(((pbf)&0x01)<<4))
+
+/* Control Opcode manipulation */
+#define nci_opcode_pack(gid, oid) (__u16)((((__u16)((gid)&0x0f))<<8)|\
+ ((__u16)((oid)&0x3f)))
+#define nci_opcode(hdr) nci_opcode_pack(hdr[0], hdr[1])
+#define nci_opcode_gid(op) (__u8)(((op)&0x0f00)>>8)
+#define nci_opcode_oid(op) (__u8)((op)&0x003f)
+
+/* Payload Length */
+#define nci_plen(hdr) (__u8)((hdr)[2])
+
+/* Connection ID */
+#define nci_conn_id(hdr) (__u8)(((hdr)[0])&0x0f)
+
+/* GID values */
+#define NCI_GID_CORE 0x0
+#define NCI_GID_RF_MGMT 0x1
+#define NCI_GID_NFCEE_MGMT 0x2
+#define NCI_GID_PROPRIETARY 0xf
+
+/* ---- NCI Packet structures ---- */
+#define NCI_CTRL_HDR_SIZE 3
+#define NCI_DATA_HDR_SIZE 3
+
+struct nci_ctrl_hdr {
+ __u8 gid; /* MT & PBF & GID */
+ __u8 oid;
+ __u8 plen;
+} __packed;
+
+struct nci_data_hdr {
+ __u8 conn_id; /* MT & PBF & ConnID */
+ __u8 rfu;
+ __u8 plen;
+} __packed;
+
+/* ------------------------ */
+/* ----- NCI Commands ---- */
+/* ------------------------ */
+#define NCI_OP_CORE_RESET_CMD nci_opcode_pack(NCI_GID_CORE, 0x00)
+
+#define NCI_OP_CORE_INIT_CMD nci_opcode_pack(NCI_GID_CORE, 0x01)
+
+#define NCI_OP_CORE_SET_CONFIG_CMD nci_opcode_pack(NCI_GID_CORE, 0x02)
+
+#define NCI_OP_CORE_CONN_CREATE_CMD nci_opcode_pack(NCI_GID_CORE, 0x04)
+struct nci_core_conn_create_cmd {
+ __u8 target_handle;
+ __u8 num_target_specific_params;
+} __packed;
+
+#define NCI_OP_CORE_CONN_CLOSE_CMD nci_opcode_pack(NCI_GID_CORE, 0x06)
+
+#define NCI_OP_RF_DISCOVER_MAP_CMD nci_opcode_pack(NCI_GID_RF_MGMT, 0x00)
+struct disc_map_config {
+ __u8 rf_protocol;
+ __u8 mode;
+ __u8 rf_interface_type;
+} __packed;
+
+struct nci_rf_disc_map_cmd {
+ __u8 num_mapping_configs;
+ struct disc_map_config mapping_configs
+ [NCI_MAX_NUM_MAPPING_CONFIGS];
+} __packed;
+
+#define NCI_OP_RF_DISCOVER_CMD nci_opcode_pack(NCI_GID_RF_MGMT, 0x03)
+struct disc_config {
+ __u8 type;
+ __u8 frequency;
+} __packed;
+
+struct nci_rf_disc_cmd {
+ __u8 num_disc_configs;
+ struct disc_config disc_configs[NCI_MAX_NUM_RF_CONFIGS];
+} __packed;
+
+#define NCI_OP_RF_DEACTIVATE_CMD nci_opcode_pack(NCI_GID_RF_MGMT, 0x06)
+struct nci_rf_deactivate_cmd {
+ __u8 type;
+} __packed;
+
+/* ----------------------- */
+/* ---- NCI Responses ---- */
+/* ----------------------- */
+#define NCI_OP_CORE_RESET_RSP nci_opcode_pack(NCI_GID_CORE, 0x00)
+struct nci_core_reset_rsp {
+ __u8 status;
+ __u8 nci_ver;
+} __packed;
+
+#define NCI_OP_CORE_INIT_RSP nci_opcode_pack(NCI_GID_CORE, 0x01)
+struct nci_core_init_rsp_1 {
+ __u8 status;
+ __le32 nfcc_features;
+ __u8 num_supported_rf_interfaces;
+ __u8 supported_rf_interfaces[0]; /* variable size array */
+ /* continuted in nci_core_init_rsp_2 */
+} __packed;
+
+struct nci_core_init_rsp_2 {
+ __u8 max_logical_connections;
+ __le16 max_routing_table_size;
+ __u8 max_control_packet_payload_length;
+ __le16 rf_sending_buffer_size;
+ __le16 rf_receiving_buffer_size;
+ __le16 manufacturer_id;
+} __packed;
+
+#define NCI_OP_CORE_SET_CONFIG_RSP nci_opcode_pack(NCI_GID_CORE, 0x02)
+
+#define NCI_OP_CORE_CONN_CREATE_RSP nci_opcode_pack(NCI_GID_CORE, 0x04)
+struct nci_core_conn_create_rsp {
+ __u8 status;
+ __u8 max_pkt_payload_size;
+ __u8 initial_num_credits;
+ __u8 conn_id;
+} __packed;
+
+#define NCI_OP_CORE_CONN_CLOSE_RSP nci_opcode_pack(NCI_GID_CORE, 0x06)
+
+#define NCI_OP_RF_DISCOVER_MAP_RSP nci_opcode_pack(NCI_GID_RF_MGMT, 0x00)
+
+#define NCI_OP_RF_DISCOVER_RSP nci_opcode_pack(NCI_GID_RF_MGMT, 0x03)
+
+#define NCI_OP_RF_DEACTIVATE_RSP nci_opcode_pack(NCI_GID_RF_MGMT, 0x06)
+
+/* --------------------------- */
+/* ---- NCI Notifications ---- */
+/* --------------------------- */
+#define NCI_OP_CORE_CONN_CREDITS_NTF nci_opcode_pack(NCI_GID_CORE, 0x07)
+struct conn_credit_entry {
+ __u8 conn_id;
+ __u8 credits;
+} __packed;
+
+struct nci_core_conn_credit_ntf {
+ __u8 num_entries;
+ struct conn_credit_entry conn_entries[NCI_MAX_NUM_CONN];
+} __packed;
+
+#define NCI_OP_RF_FIELD_INFO_NTF nci_opcode_pack(NCI_GID_CORE, 0x08)
+struct nci_rf_field_info_ntf {
+ __u8 rf_field_status;
+} __packed;
+
+#define NCI_OP_RF_ACTIVATE_NTF nci_opcode_pack(NCI_GID_RF_MGMT, 0x05)
+struct rf_tech_specific_params_nfca_poll {
+ __u16 sens_res;
+ __u8 nfcid1_len; /* 0, 4, 7, or 10 Bytes */
+ __u8 nfcid1[10];
+ __u8 sel_res_len; /* 0 or 1 Bytes */
+ __u8 sel_res;
+} __packed;
+
+struct activation_params_nfca_poll_iso_dep {
+ __u8 rats_res_len;
+ __u8 rats_res[20];
+};
+
+struct nci_rf_activate_ntf {
+ __u8 target_handle;
+ __u8 rf_protocol;
+ __u8 rf_tech_and_mode;
+ __u8 rf_tech_specific_params_len;
+
+ union {
+ struct rf_tech_specific_params_nfca_poll nfca_poll;
+ } rf_tech_specific_params;
+
+ __u8 rf_interface_type;
+ __u8 activation_params_len;
+
+ union {
+ struct activation_params_nfca_poll_iso_dep nfca_poll_iso_dep;
+ } activation_params;
+
+} __packed;
+
+#define NCI_OP_RF_DEACTIVATE_NTF nci_opcode_pack(NCI_GID_RF_MGMT, 0x06)
+
+#endif /* __NCI_H */
diff --git a/include/net/nfc/nci_core.h b/include/net/nfc/nci_core.h
new file mode 100644
index 0000000..f8f47a7
--- /dev/null
+++ b/include/net/nfc/nci_core.h
@@ -0,0 +1,177 @@
+/*
+ * 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 <[email protected]>
+ *
+ * Acknowledgements:
+ * This file is based on hci_core.h, 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
+ *
+ */
+
+#ifndef __NCI_CORE_H
+#define __NCI_CORE_H
+
+#include <linux/interrupt.h>
+#include <linux/skbuff.h>
+
+#include <net/nfc/nfc.h>
+#include <net/nfc/nci.h>
+
+/* NCI device state */
+enum {
+ NCI_INIT,
+ NCI_UP,
+ NCI_DISCOVERY,
+ NCI_POLL_ACTIVE,
+};
+
+/* NCI timeouts */
+#define NCI_RESET_TIMEOUT 5000
+#define NCI_INIT_TIMEOUT 5000
+#define NCI_RF_DISC_TIMEOUT 5000
+#define NCI_RF_DEACTIVATE_TIMEOUT 5000
+#define NCI_CMD_TIMEOUT 5000
+
+struct nci_dev;
+
+struct nci_ops {
+ int (*open)(struct nci_dev *ndev);
+ int (*close)(struct nci_dev *ndev);
+ int (*send)(struct sk_buff *skb);
+};
+
+/* Reserved for drivers usage */
+#define NCI_SKB_RESERVE 4
+
+static inline struct sk_buff *nci_skb_alloc(unsigned int len, gfp_t how)
+{
+ struct sk_buff *skb;
+
+ skb = alloc_skb(len + NCI_SKB_RESERVE, how);
+ if (skb)
+ skb_reserve(skb, NCI_SKB_RESERVE);
+
+ return skb;
+}
+
+#define NCI_MAX_SUPPORTED_RF_INTERFACES 4
+
+/* NCI Core structures */
+struct nci_dev {
+ struct nfc_dev *nfc_dev;
+ struct nci_ops *ops;
+
+ unsigned long flags;
+
+ atomic_t cmd_cnt;
+ atomic_t credits_cnt;
+
+ struct timer_list cmd_timer;
+
+ struct tasklet_struct cmd_task;
+ struct tasklet_struct rx_task;
+ struct tasklet_struct tx_data_task;
+
+ struct sk_buff_head cmd_q;
+ struct sk_buff_head rx_q;
+ struct sk_buff_head tx_data_q;
+
+ struct mutex req_lock;
+ wait_queue_head_t req_wait_q;
+ __u32 req_status;
+ __u32 req_result;
+
+ void *driver_data;
+
+ __u32 poll_prots;
+ __u32 target_available_prots;
+ __u32 target_active_prot;
+
+ /* received during NCI_OP_CORE_RESET_RSP */
+ __u8 nci_ver;
+
+ /* received during NCI_OP_CORE_INIT_RSP */
+ __u32 nfcc_features;
+ __u8 num_supported_rf_interfaces;
+ __u8 supported_rf_interfaces
+ [NCI_MAX_SUPPORTED_RF_INTERFACES];
+ __u8 max_logical_connections;
+ __u16 max_routing_table_size;
+ __u8 max_control_packet_payload_length;
+ __u16 rf_sending_buffer_size;
+ __u16 rf_receiving_buffer_size;
+ __u16 manufacturer_id;
+
+ /* received during NCI_OP_CORE_CONN_CREATE_RSP for static conn 0 */
+ __u8 max_pkt_payload_size;
+ __u8 initial_num_credits;
+ __u8 conn_id;
+
+ /* stored during nci_data_exchange */
+ data_exchange_cb_t data_exchange_cb;
+ void *data_exchange_cb_context;
+ struct sk_buff *rx_data_reassembly;
+};
+
+/* ----- NCI Devices ----- */
+struct nci_dev *nci_allocate_device(struct nci_ops *ops,
+ __u32 supported_protocols);
+void nci_free_device(struct nci_dev *ndev);
+int nci_register_device(struct nci_dev *ndev);
+void nci_unregister_device(struct nci_dev *ndev);
+int nci_recv_frame(struct sk_buff *skb);
+
+static inline void nci_set_parent_dev(struct nci_dev *ndev, struct device *dev)
+{
+ nfc_set_parent_dev(ndev->nfc_dev, dev);
+}
+
+static inline void nci_set_drvdata(struct nci_dev *ndev, void *data)
+{
+ ndev->driver_data = data;
+}
+
+static inline void *nci_get_drvdata(struct nci_dev *ndev)
+{
+ return ndev->driver_data;
+}
+
+void nci_rsp_packet(struct nci_dev *ndev, struct sk_buff *skb);
+void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb);
+void nci_rx_data_packet(struct nci_dev *ndev, struct sk_buff *skb);
+int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload);
+int nci_send_data(struct nci_dev *ndev, __u8 conn_id, struct sk_buff *skb);
+void nci_data_exchange_complete(struct nci_dev *ndev, struct sk_buff *skb,
+ int err);
+
+/* ----- NCI requests ----- */
+#define NCI_REQ_DONE 0
+#define NCI_REQ_PEND 1
+#define NCI_REQ_CANCELED 2
+
+#define nci_req_lock(ndev) mutex_lock(&ndev->req_lock)
+#define nci_req_unlock(ndev) mutex_unlock(&ndev->req_lock)
+
+void nci_req_complete(struct nci_dev *ndev, int result);
+
+/* ----- NCI status code ----- */
+int nci_to_errno(__u8 code);
+
+#endif /* __NCI_CORE_H */
diff --git a/net/nfc/Kconfig b/net/nfc/Kconfig
index 33e095b..58cddad 100644
--- a/net/nfc/Kconfig
+++ b/net/nfc/Kconfig
@@ -13,4 +13,6 @@ menuconfig NFC
To compile this support as a module, choose M here: the module will
be called nfc.

+source "net/nfc/nci/Kconfig"
+
source "drivers/nfc/Kconfig"
diff --git a/net/nfc/Makefile b/net/nfc/Makefile
index 16250c3..fbb550f 100644
--- a/net/nfc/Makefile
+++ b/net/nfc/Makefile
@@ -3,5 +3,6 @@
#

obj-$(CONFIG_NFC) += nfc.o
+obj-$(CONFIG_NFC_NCI) += nci/

nfc-objs := core.o netlink.o af_nfc.o rawsock.o
diff --git a/net/nfc/nci/Kconfig b/net/nfc/nci/Kconfig
new file mode 100644
index 0000000..decdc49
--- /dev/null
+++ b/net/nfc/nci/Kconfig
@@ -0,0 +1,10 @@
+config NFC_NCI
+ depends on NFC && EXPERIMENTAL
+ tristate "NCI protocol support (EXPERIMENTAL)"
+ default n
+ help
+ NCI (NFC Controller Interface) is a communication protocol between
+ an NFC Controller (NFCC) and a Device Host (DH).
+
+ Say Y here to compile NCI support into the kernel or say M to
+ compile it as module (nci).
diff --git a/net/nfc/nci/Makefile b/net/nfc/nci/Makefile
new file mode 100644
index 0000000..b2ccdd2
--- /dev/null
+++ b/net/nfc/nci/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the Linux NFC NCI layer.
+#
+
+obj-$(CONFIG_NFC_NCI) += nci.o
+
+nci-objs := nci_core.o nci_data.o nci_lib.o nci_ntf.o nci_rsp.o
\ No newline at end of file
diff --git a/net/nfc/nci/nci_core.c b/net/nfc/nci/nci_core.c
new file mode 100644
index 0000000..78cde6d
--- /dev/null
+++ b/net/nfc/nci/nci_core.c
@@ -0,0 +1,750 @@
+/*
+ * 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 <[email protected]>
+ *
+ * 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
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/wait.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_task(unsigned long arg);
+static void nci_rx_task(unsigned long arg);
+static void nci_tx_data_task(unsigned long arg);
+
+/* ---- 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;
+ wake_up_interruptible(&ndev->req_wait_q);
+ }
+}
+
+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;
+ wake_up_interruptible(&ndev->req_wait_q);
+ }
+}
+
+/* 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)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ int rc = 0;
+
+ ndev->req_status = NCI_REQ_PEND;
+
+ add_wait_queue(&ndev->req_wait_q, &wait);
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ req(ndev, opt);
+ schedule_timeout(timeout);
+
+ remove_wait_queue(&ndev->req_wait_q, &wait);
+
+ if (signal_pending(current))
+ return -EINTR;
+
+ 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;
+ }
+
+ 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 */
+ nci_req_lock(ndev);
+ rc = __nci_request(ndev, req, opt, timeout);
+ nci_req_unlock(ndev);
+
+ return rc;
+}
+
+static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
+{
+ nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 0, NULL);
+}
+
+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 nci_core_conn_create_cmd conn_cmd;
+ int i;
+
+ /* create static rf connection */
+ conn_cmd.target_handle = 0;
+ conn_cmd.num_target_specific_params = 0;
+ nci_send_cmd(ndev, NCI_OP_CORE_CONN_CREATE_CMD, 2, &conn_cmd);
+
+ /* set rf mapping configurations */
+ cmd.num_mapping_configs = 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) {
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .mode = NCI_DISC_MAP_MODE_BOTH;
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .rf_interface_type = NCI_RF_INTERFACE_ISO_DEP;
+ cmd.num_mapping_configs++;
+ } else if (ndev->supported_rf_interfaces[i] ==
+ NCI_RF_INTERFACE_NFC_DEP) {
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .mode = NCI_DISC_MAP_MODE_BOTH;
+ cmd.mapping_configs[cmd.num_mapping_configs]
+ .rf_interface_type = NCI_RF_INTERFACE_NFC_DEP;
+ cmd.num_mapping_configs++;
+ }
+
+ if (cmd.num_mapping_configs == NCI_MAX_NUM_MAPPING_CONFIGS)
+ break;
+ }
+
+ nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
+ (1 + (cmd.num_mapping_configs*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].type =
+ NCI_DISCOVERY_TYPE_POLL_A_PASSIVE;
+ 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].type =
+ NCI_DISCOVERY_TYPE_POLL_B_PASSIVE;
+ 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].type =
+ NCI_DISCOVERY_TYPE_POLL_F_PASSIVE;
+ 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;
+
+ nci_req_lock(ndev);
+
+ 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 */
+ tasklet_kill(&ndev->cmd_task);
+ tasklet_kill(&ndev->rx_task);
+ tasklet_kill(&ndev->tx_data_task);
+
+ skb_queue_purge(&ndev->cmd_q);
+ skb_queue_purge(&ndev->rx_q);
+ skb_queue_purge(&ndev->tx_data_q);
+
+ ndev->ops->close(ndev);
+ ndev->flags = 0;
+ }
+
+done:
+ nci_req_unlock(ndev);
+ return rc;
+}
+
+static int nci_close_device(struct nci_dev *ndev)
+{
+ nci_req_cancel(ndev, ENODEV);
+ nci_req_lock(ndev);
+
+ if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
+ del_timer_sync(&ndev->cmd_timer);
+ nci_req_unlock(ndev);
+ return 0;
+ }
+
+ /* Kill RX and TX tasks */
+ tasklet_kill(&ndev->rx_task);
+ tasklet_kill(&ndev->tx_data_task);
+
+ /* 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);
+
+ /* Kill cmd task */
+ tasklet_kill(&ndev->cmd_task);
+
+ /* Drop queues */
+ skb_queue_purge(&ndev->cmd_q);
+ skb_queue_purge(&ndev->rx_q);
+ skb_queue_purge(&ndev->tx_data_q);
+
+ /* After this point our queues are empty
+ * and no tasks are scheduled. */
+ ndev->ops->close(ndev);
+
+ /* Clear flags */
+ ndev->flags = 0;
+
+ nci_req_unlock(ndev);
+
+ return 0;
+}
+
+/* NCI command timer function */
+static void nci_cmd_timer(unsigned long arg)
+{
+ struct nci_dev *ndev = (void *) arg;
+
+ nfc_dbg("entry");
+
+ atomic_set(&ndev->cmd_cnt, 1);
+ tasklet_schedule(&ndev->cmd_task);
+}
+
+static int nci_dev_up(struct nfc_dev *nfc_dev)
+{
+ struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+ nfc_dbg("entry");
+
+ return nci_open_device(ndev);
+}
+
+static int nci_dev_down(struct nfc_dev *nfc_dev)
+{
+ struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
+
+ nfc_dbg("entry");
+
+ 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;
+
+ nfc_dbg("entry");
+
+ if (test_bit(NCI_DISCOVERY, &ndev->flags)) {
+ nfc_err("unable to start poll, since poll is already active");
+ return -EBUSY;
+ }
+
+ if (test_bit(NCI_POLL_ACTIVE, &ndev->flags)) {
+ nfc_dbg("target already active, first deactivate...");
+
+ 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);
+
+ nfc_dbg("entry");
+
+ if (!test_bit(NCI_DISCOVERY, &ndev->flags)) {
+ nfc_err("unable to stop poll, since poll is not active");
+ 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);
+
+ nfc_dbg("entry, target_idx %d, protocol 0x%x", target_idx, protocol);
+
+ if (!test_bit(NCI_POLL_ACTIVE, &ndev->flags)) {
+ nfc_err("there is no available target to activate");
+ return -EINVAL;
+ }
+
+ if (ndev->target_active_prot) {
+ nfc_err("there is already an active target");
+ return -EBUSY;
+ }
+
+ if (!(ndev->target_available_prots & (1 << protocol))) {
+ nfc_err("target does not support the requested protocol 0x%x",
+ 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);
+
+ nfc_dbg("entry, target_idx %d", target_idx);
+
+ if (!ndev->target_active_prot) {
+ nfc_err("unable to deactivate target, no active target");
+ 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);
+
+ nfc_dbg("entry, target_idx %d, len %d", target_idx, skb->len);
+
+ if (!ndev->target_active_prot) {
+ nfc_err("unable to exchange data, no active target");
+ return -EINVAL;
+ }
+
+ /* store cb and context to be used on receiving data */
+ ndev->data_exchange_cb = cb;
+ ndev->data_exchange_cb_context = cb_context;
+
+ return nci_send_data(ndev, ndev->conn_id, skb);
+}
+
+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)
+{
+ struct nci_dev *ndev = NULL;
+
+ nfc_dbg("entry, supported_protocols 0x%x", supported_protocols);
+
+ if (!ops->open || !ops->close || !ops->send)
+ goto exit;
+
+ if (!supported_protocols)
+ goto exit;
+
+ ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
+ if (!ndev)
+ goto exit;
+
+ ndev->ops = ops;
+
+ ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
+ supported_protocols);
+ if (!ndev->nfc_dev)
+ goto free_exit;
+
+ nfc_set_drvdata(ndev->nfc_dev, ndev);
+
+ goto exit;
+
+free_exit:
+ kfree(ndev);
+
+exit:
+ return ndev;
+}
+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_dbg("entry");
+
+ 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;
+
+ nfc_dbg("entry");
+
+ rc = nfc_register_device(ndev->nfc_dev);
+ if (rc)
+ return rc;
+
+ ndev->flags = 0;
+
+ tasklet_init(&ndev->cmd_task, nci_cmd_task,
+ (unsigned long) ndev);
+ tasklet_init(&ndev->rx_task, nci_rx_task,
+ (unsigned long) ndev);
+ tasklet_init(&ndev->tx_data_task, nci_tx_data_task,
+ (unsigned long) ndev);
+
+ skb_queue_head_init(&ndev->cmd_q);
+ skb_queue_head_init(&ndev->rx_q);
+ skb_queue_head_init(&ndev->tx_data_q);
+
+ setup_timer(&ndev->cmd_timer, nci_cmd_timer,
+ (unsigned long) ndev);
+
+ init_waitqueue_head(&ndev->req_wait_q);
+ mutex_init(&ndev->req_lock);
+
+ return 0;
+}
+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)
+{
+ nfc_dbg("entry");
+
+ nci_close_device(ndev);
+ 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;
+
+ nfc_dbg("entry, len %d", 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 task */
+ skb_queue_tail(&ndev->rx_q, skb);
+ tasklet_schedule(&ndev->rx_task);
+
+ 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;
+
+ nfc_dbg("entry, len %d", 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;
+
+ nfc_dbg("entry, opcode 0x%x, plen %d", opcode, plen);
+
+ skb = nci_skb_alloc((NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
+ if (!skb) {
+ nfc_err("no memory for command");
+ 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);
+ tasklet_schedule(&ndev->cmd_task);
+
+ return 0;
+}
+
+/* ---- NCI TX Data task ---- */
+
+static void nci_tx_data_task(unsigned long arg)
+{
+ struct nci_dev *ndev = (struct nci_dev *) arg;
+ struct sk_buff *skb;
+
+ nfc_dbg("entry, credits_cnt %d", atomic_read(&ndev->credits_cnt));
+
+ /* Send queued tx data */
+ while (atomic_read(&ndev->credits_cnt)) {
+ skb = skb_dequeue(&ndev->tx_data_q);
+ if (!skb)
+ return;
+
+ atomic_dec(&ndev->credits_cnt);
+
+ nfc_dbg("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d",
+ nci_pbf(skb->data),
+ nci_conn_id(skb->data),
+ nci_plen(skb->data));
+
+ nci_send_frame(skb);
+ }
+}
+
+/* ----- NCI RX task (data & control) ----- */
+
+static void nci_rx_task(unsigned long arg)
+{
+ struct nci_dev *ndev = (struct nci_dev *) arg;
+ 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:
+ nfc_err("unknown MT 0x%x", nci_mt(skb->data));
+ kfree_skb(skb);
+ break;
+ }
+ }
+}
+
+/* ----- NCI TX CMD task ----- */
+
+static void nci_cmd_task(unsigned long arg)
+{
+ struct nci_dev *ndev = (struct nci_dev *) arg;
+ struct sk_buff *skb;
+
+ nfc_dbg("entry, cmd_cnt %d", 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);
+
+ nfc_dbg("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d",
+ 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));
+ }
+}
diff --git a/net/nfc/nci/nci_data.c b/net/nfc/nci/nci_data.c
new file mode 100644
index 0000000..ef3d9eb
--- /dev/null
+++ b/net/nfc/nci/nci_data.c
@@ -0,0 +1,252 @@
+/*
+ * 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 <[email protected]>
+ *
+ * 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
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/wait.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>
+
+/* Complete data exchange transaction and forward skb to nfc core */
+void nci_data_exchange_complete(struct nci_dev *ndev,
+ struct sk_buff *skb,
+ int err)
+{
+ data_exchange_cb_t cb = ndev->data_exchange_cb;
+ void *cb_context = ndev->data_exchange_cb_context;
+
+ nfc_dbg("entry, len %d, err %d", ((skb) ? (skb->len) : (0)), err);
+
+ if (cb) {
+ ndev->data_exchange_cb = NULL;
+ ndev->data_exchange_cb_context = 0;
+
+ /* forward skb to nfc core */
+ cb(cb_context, skb, err);
+ } else if (skb) {
+ nfc_err("no rx callback, dropping rx data...");
+
+ /* no waiting callback, free skb */
+ kfree_skb(skb);
+ }
+}
+
+/* ----------------- NCI TX Data ----------------- */
+
+static inline void nci_push_data_hdr(struct nci_dev *ndev,
+ __u8 conn_id,
+ struct sk_buff *skb,
+ __u8 pbf)
+{
+ struct nci_data_hdr *hdr;
+ int plen = skb->len;
+
+ hdr = (struct nci_data_hdr *) skb_push(skb, NCI_DATA_HDR_SIZE);
+ hdr->conn_id = conn_id;
+ hdr->rfu = 0;
+ hdr->plen = plen;
+
+ nci_mt_set((__u8 *)hdr, NCI_MT_DATA_PKT);
+ nci_pbf_set((__u8 *)hdr, pbf);
+
+ skb->dev = (void *) ndev;
+}
+
+static int nci_queue_tx_data_frags(struct nci_dev *ndev,
+ __u8 conn_id,
+ struct sk_buff *skb) {
+ int total_len = skb->len;
+ unsigned char *data = skb->data;
+ unsigned long flags;
+ struct sk_buff_head frags_q;
+ struct sk_buff *skb_frag;
+ int frag_len;
+ int rc = 0;
+
+ nfc_dbg("entry, conn_id 0x%x, total_len %d", conn_id, total_len);
+
+ __skb_queue_head_init(&frags_q);
+
+ while (total_len) {
+ frag_len = min(total_len, (int)ndev->max_pkt_payload_size);
+
+ skb_frag = nci_skb_alloc((NCI_DATA_HDR_SIZE + frag_len),
+ GFP_KERNEL);
+ if (skb_frag == NULL) {
+ rc = -ENOMEM;
+ goto free_exit;
+ }
+ skb_reserve(skb_frag, NCI_DATA_HDR_SIZE);
+
+ /* first, copy the data */
+ memcpy(skb_put(skb_frag, frag_len), data, frag_len);
+
+ /* second, set the header */
+ nci_push_data_hdr(ndev, conn_id, skb_frag,
+ ((total_len == frag_len) ? (NCI_PBF_LAST) : (NCI_PBF_CONT)));
+
+ __skb_queue_tail(&frags_q, skb_frag);
+
+ data += frag_len;
+ total_len -= frag_len;
+
+ nfc_dbg("frag_len %d, remaining total_len %d",
+ frag_len, total_len);
+ }
+
+ /* queue all fragments atomically */
+ spin_lock_irqsave(&ndev->tx_data_q.lock, flags);
+
+ while ((skb_frag = __skb_dequeue(&frags_q)) != NULL)
+ __skb_queue_tail(&ndev->tx_data_q, skb_frag);
+
+ spin_unlock_irqrestore(&ndev->tx_data_q.lock, flags);
+
+ /* free the original skb */
+ kfree_skb(skb);
+
+ goto exit;
+
+free_exit:
+ while ((skb_frag = __skb_dequeue(&frags_q)) != NULL)
+ kfree_skb(skb_frag);
+
+exit:
+ return rc;
+}
+
+/* Send NCI data */
+int nci_send_data(struct nci_dev *ndev, __u8 conn_id, struct sk_buff *skb)
+{
+ int rc = 0;
+
+ nfc_dbg("entry, conn_id 0x%x, plen %d", conn_id, skb->len);
+
+ /* check if the packet need to be fragmented */
+ if (skb->len <= ndev->max_pkt_payload_size) {
+ /* no need to fragment packet */
+
+ /* reserve header space for nci and driver */
+ if (skb_cow_head(skb, (NCI_DATA_HDR_SIZE + NCI_SKB_RESERVE))) {
+ nfc_err("error adding tx header data");
+ rc = -ENOMEM;
+ goto free_exit;
+ }
+
+ nci_push_data_hdr(ndev, conn_id, skb, NCI_PBF_LAST);
+
+ skb_queue_tail(&ndev->tx_data_q, skb);
+ } else {
+ /* fragment packet and queue the fragments */
+ rc = nci_queue_tx_data_frags(ndev, conn_id, skb);
+ if (rc) {
+ nfc_err("failed to fragment tx data packet");
+ goto free_exit;
+ }
+ }
+
+ tasklet_schedule(&ndev->tx_data_task);
+
+ goto exit;
+
+free_exit:
+ kfree_skb(skb);
+
+exit:
+ return rc;
+}
+
+/* ----------------- NCI RX Data ----------------- */
+
+static void nci_add_rx_data_frag(struct nci_dev *ndev,
+ struct sk_buff *skb,
+ __u8 pbf)
+{
+ int reassembly_len;
+ int err = 0;
+
+ if (ndev->rx_data_reassembly) {
+ reassembly_len = ndev->rx_data_reassembly->len;
+
+ /* first, make enough room for the already accumulated data */
+ if (skb_cow_head(skb, reassembly_len)) {
+ nfc_err("error adding room for accumulated rx data");
+
+ kfree_skb(skb);
+ skb = 0;
+
+ kfree_skb(ndev->rx_data_reassembly);
+ ndev->rx_data_reassembly = 0;
+
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ /* second, combine the two fragments */
+ memcpy(skb_push(skb, reassembly_len),
+ ndev->rx_data_reassembly->data,
+ reassembly_len);
+
+ /* third, free old reassembly */
+ kfree_skb(ndev->rx_data_reassembly);
+ ndev->rx_data_reassembly = 0;
+ }
+
+ if (pbf == NCI_PBF_CONT) {
+ /* need to wait for next fragment, store skb and exit */
+ ndev->rx_data_reassembly = skb;
+ return;
+ }
+
+exit:
+ nci_data_exchange_complete(ndev, skb, err);
+}
+
+/* Rx Data packet */
+void nci_rx_data_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ __u8 pbf = nci_pbf(skb->data);
+
+ nfc_dbg("entry, len %d", skb->len);
+
+ nfc_dbg("NCI RX: MT=data, PBF=%d, conn_id=%d, plen=%d",
+ nci_pbf(skb->data),
+ nci_conn_id(skb->data),
+ nci_plen(skb->data));
+
+ /* strip the nci data header */
+ skb_pull(skb, NCI_DATA_HDR_SIZE);
+
+ if (ndev->target_active_prot == NFC_PROTO_MIFARE) {
+ /* frame I/F => remove the status byte */
+ nfc_dbg("NFC_PROTO_MIFARE => remove the status byte");
+ skb_trim(skb, (skb->len - 1));
+ }
+
+ nci_add_rx_data_frag(ndev, skb, pbf);
+}
diff --git a/net/nfc/nci/nci_lib.c b/net/nfc/nci/nci_lib.c
new file mode 100644
index 0000000..b19dc2f
--- /dev/null
+++ b/net/nfc/nci/nci_lib.c
@@ -0,0 +1,94 @@
+/*
+ * 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 <[email protected]>
+ *
+ * Acknowledgements:
+ * This file is based on lib.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
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+
+#include <net/nfc/nci.h>
+
+/* NCI status codes to Unix errno mapping */
+int nci_to_errno(__u8 code)
+{
+ switch (code) {
+ case NCI_STATUS_OK:
+ return 0;
+
+ case NCI_STATUS_REJECTED:
+ return -EBUSY;
+
+ case NCI_STATUS_MESSAGE_CORRUPTED:
+ return -EBADMSG;
+
+ case NCI_STATUS_BUFFER_FULL:
+ return -ENOBUFS;
+
+ case NCI_STATUS_NOT_INITIALIZED:
+ return -EHOSTDOWN;
+
+ case NCI_STATUS_SYNTAX_ERROR:
+ case NCI_STATUS_SEMANTIC_ERROR:
+ case NCI_STATUS_INVALID_PARAM:
+ case NCI_STATUS_RF_PROTOCOL_ERROR:
+ case NCI_STATUS_NFCEE_PROTOCOL_ERROR:
+ return -EPROTO;
+
+ case NCI_STATUS_UNKNOWN_GID:
+ case NCI_STATUS_UNKNOWN_OID:
+ return -EBADRQC;
+
+ case NCI_STATUS_MESSAGE_SIZE_EXCEEDED:
+ return -EMSGSIZE;
+
+ case NCI_STATUS_DISCOVERY_ALREADY_STARTED:
+ return -EALREADY;
+
+ case NCI_STATUS_DISCOVERY_TARGET_ACTIVATION_FAILED:
+ case NCI_STATUS_NFCEE_INTERFACE_ACTIVATION_FAILED:
+ return -ECONNREFUSED;
+
+ case NCI_STATUS_RF_TRANSMISSION_ERROR:
+ case NCI_STATUS_NFCEE_TRANSMISSION_ERROR:
+ return -ECOMM;
+
+ case NCI_STATUS_RF_TIMEOUT_ERROR:
+ case NCI_STATUS_NFCEE_TIMEOUT_ERROR:
+ return -ETIMEDOUT;
+
+ case NCI_STATUS_RF_LINK_LOSS_ERROR:
+ return -ENOLINK;
+
+ case NCI_STATUS_MAX_ACTIVE_NFCEE_INTERFACES_REACHED:
+ return -EDQUOT;
+
+ case NCI_STATUS_FAILED:
+ default:
+ return -ENOSYS;
+ }
+}
+EXPORT_SYMBOL(nci_to_errno);
diff --git a/net/nfc/nci/nci_ntf.c b/net/nfc/nci/nci_ntf.c
new file mode 100644
index 0000000..a8ecd93
--- /dev/null
+++ b/net/nfc/nci/nci_ntf.c
@@ -0,0 +1,264 @@
+/*
+ * 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 <[email protected]>
+ *
+ * Acknowledgements:
+ * This file is based on hci_event.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
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.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>
+
+/* Handle NCI Notification packets */
+
+static void nci_core_conn_credits_ntf_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ struct nci_core_conn_credit_ntf *ntf = (void *) skb->data;
+ int i;
+
+ nfc_dbg("entry, num_entries %d", ntf->num_entries);
+
+ if (ntf->num_entries > NCI_MAX_NUM_CONN)
+ ntf->num_entries = NCI_MAX_NUM_CONN;
+
+ tasklet_disable(&ndev->tx_data_task);
+
+ /* update the credits */
+ for (i = 0; i < ntf->num_entries; i++) {
+ nfc_dbg("entry[%d]: conn_id %d, credits %d", i,
+ ntf->conn_entries[i].conn_id,
+ ntf->conn_entries[i].credits);
+
+ if (ntf->conn_entries[i].conn_id == ndev->conn_id) {
+ /* found static rf connection */
+ atomic_add(ntf->conn_entries[i].credits,
+ &ndev->credits_cnt);
+ }
+ }
+
+ /* trigger the next tx */
+ if (!skb_queue_empty(&ndev->tx_data_q))
+ tasklet_schedule(&ndev->tx_data_task);
+
+ tasklet_enable(&ndev->tx_data_task);
+}
+
+static void nci_rf_field_info_ntf_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ struct nci_rf_field_info_ntf *ntf = (void *) skb->data;
+
+ nfc_dbg("entry, rf_field_status %d", ntf->rf_field_status);
+}
+
+static int nci_rf_activate_nfca_passive_poll(struct nci_dev *ndev,
+ struct nci_rf_activate_ntf *ntf, __u8 *data)
+{
+ struct rf_tech_specific_params_nfca_poll *nfca_poll;
+ struct activation_params_nfca_poll_iso_dep *nfca_poll_iso_dep;
+
+ nfca_poll = &ntf->rf_tech_specific_params.nfca_poll;
+ nfca_poll_iso_dep = &ntf->activation_params.nfca_poll_iso_dep;
+
+ nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data));
+ data += 2;
+
+ nfca_poll->nfcid1_len = *data++;
+
+ nfc_dbg("sens_res 0x%x, nfcid1_len %d",
+ nfca_poll->sens_res,
+ nfca_poll->nfcid1_len);
+
+ memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len);
+ data += nfca_poll->nfcid1_len;
+
+ nfca_poll->sel_res_len = *data++;
+
+ if (nfca_poll->sel_res_len != 0)
+ nfca_poll->sel_res = *data++;
+
+ ntf->rf_interface_type = *data++;
+ ntf->activation_params_len = *data++;
+
+ nfc_dbg("sel_res_len %d, sel_res 0x%x, rf_interface_type %d, activation_params_len %d",
+ nfca_poll->sel_res_len,
+ nfca_poll->sel_res,
+ ntf->rf_interface_type,
+ ntf->activation_params_len);
+
+ switch (ntf->rf_interface_type) {
+ case NCI_RF_INTERFACE_ISO_DEP:
+ nfca_poll_iso_dep->rats_res_len = *data++;
+ if (nfca_poll_iso_dep->rats_res_len > 0) {
+ memcpy(nfca_poll_iso_dep->rats_res,
+ data,
+ nfca_poll_iso_dep->rats_res_len);
+ }
+ break;
+
+ case NCI_RF_INTERFACE_FRAME:
+ /* no activation params */
+ break;
+
+ default:
+ nfc_err("unsupported rf_interface_type 0x%x",
+ ntf->rf_interface_type);
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+static void nci_target_found(struct nci_dev *ndev,
+ struct nci_rf_activate_ntf *ntf)
+{
+ struct nfc_target nfc_tgt;
+
+ if (ntf->rf_protocol == NCI_RF_PROTOCOL_T2T) /* T2T MifareUL */
+ nfc_tgt.supported_protocols = NFC_PROTO_MIFARE_MASK;
+ else if (ntf->rf_protocol == NCI_RF_PROTOCOL_ISO_DEP) /* 4A */
+ nfc_tgt.supported_protocols = NFC_PROTO_ISO14443_MASK;
+
+ nfc_tgt.sens_res = ntf->rf_tech_specific_params.nfca_poll.sens_res;
+ nfc_tgt.sel_res = ntf->rf_tech_specific_params.nfca_poll.sel_res;
+
+ if (!(nfc_tgt.supported_protocols & ndev->poll_prots)) {
+ nfc_dbg("the target found does not have the desired protocol");
+ return;
+ }
+
+ nfc_dbg("new target found, supported_protocols 0x%x",
+ nfc_tgt.supported_protocols);
+
+ ndev->target_available_prots = nfc_tgt.supported_protocols;
+
+ nfc_targets_found(ndev->nfc_dev, &nfc_tgt, 1);
+}
+
+static void nci_rf_activate_ntf_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ struct nci_rf_activate_ntf ntf;
+ __u8 *data = skb->data;
+ int rc = -1;
+
+ clear_bit(NCI_DISCOVERY, &ndev->flags);
+ set_bit(NCI_POLL_ACTIVE, &ndev->flags);
+
+ ntf.target_handle = *data++;
+ ntf.rf_protocol = *data++;
+ ntf.rf_tech_and_mode = *data++;
+ ntf.rf_tech_specific_params_len = *data++;
+
+ nfc_dbg("target_handle %d, rf_protocol 0x%x, rf_tech_and_mode 0x%x, rf_tech_specific_params_len %d",
+ ntf.target_handle,
+ ntf.rf_protocol,
+ ntf.rf_tech_and_mode,
+ ntf.rf_tech_specific_params_len);
+
+ switch (ntf.rf_tech_and_mode) {
+ case NCI_NFC_A_PASSIVE_POLL_MODE:
+ rc = nci_rf_activate_nfca_passive_poll(ndev, &ntf,
+ data);
+ break;
+
+ default:
+ nfc_err("unsupported rf_tech_and_mode 0x%x",
+ ntf.rf_tech_and_mode);
+ return;
+ }
+
+ if (!rc)
+ nci_target_found(ndev, &ntf);
+}
+
+static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ __u8 type = skb->data[0];
+
+ nfc_dbg("entry, type 0x%x", type);
+
+ clear_bit(NCI_POLL_ACTIVE, &ndev->flags);
+ ndev->target_active_prot = 0;
+
+ /* drop tx data queue */
+ tasklet_disable(&ndev->tx_data_task);
+ skb_queue_purge(&ndev->tx_data_q);
+ tasklet_enable(&ndev->tx_data_task);
+
+ /* drop partial rx data packet */
+ if (ndev->rx_data_reassembly) {
+ kfree_skb(ndev->rx_data_reassembly);
+ ndev->rx_data_reassembly = 0;
+ }
+
+ /* complete the data exchange transaction, if exists */
+ if (ndev->data_exchange_cb)
+ nci_data_exchange_complete(ndev, NULL, -EIO);
+}
+
+void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ __u16 ntf_opcode = nci_opcode(skb->data);
+
+ nfc_dbg("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d",
+ nci_pbf(skb->data),
+ nci_opcode_gid(ntf_opcode),
+ nci_opcode_oid(ntf_opcode),
+ nci_plen(skb->data));
+
+ /* strip the nci control header */
+ skb_pull(skb, NCI_CTRL_HDR_SIZE);
+
+ switch (ntf_opcode) {
+ case NCI_OP_CORE_CONN_CREDITS_NTF:
+ nci_core_conn_credits_ntf_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_FIELD_INFO_NTF:
+ nci_rf_field_info_ntf_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_ACTIVATE_NTF:
+ nci_rf_activate_ntf_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_DEACTIVATE_NTF:
+ nci_rf_deactivate_ntf_packet(ndev, skb);
+ break;
+
+ default:
+ nfc_err("unknown ntf opcode 0x%x", ntf_opcode);
+ break;
+ }
+
+ kfree_skb(skb);
+}
diff --git a/net/nfc/nci/nci_rsp.c b/net/nfc/nci/nci_rsp.c
new file mode 100644
index 0000000..0e71952
--- /dev/null
+++ b/net/nfc/nci/nci_rsp.c
@@ -0,0 +1,226 @@
+/*
+ * 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 <[email protected]>
+ *
+ * Acknowledgements:
+ * This file is based on hci_event.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
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/skbuff.h>
+
+#include "../nfc.h"
+#include <net/nfc/nci.h>
+#include <net/nfc/nci_core.h>
+
+/* Handle NCI Response packets */
+
+static void nci_core_reset_rsp_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ struct nci_core_reset_rsp *rsp = (void *) skb->data;
+
+ nfc_dbg("entry, status 0x%x", rsp->status);
+
+ if (rsp->status == NCI_STATUS_OK)
+ ndev->nci_ver = rsp->nci_ver;
+
+ nfc_dbg("nci_ver 0x%x", ndev->nci_ver);
+
+ nci_req_complete(ndev, rsp->status);
+}
+
+static void nci_core_init_rsp_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ struct nci_core_init_rsp_1 *rsp_1 = (void *) skb->data;
+ struct nci_core_init_rsp_2 *rsp_2;
+
+ nfc_dbg("entry, status 0x%x", rsp_1->status);
+
+ if (rsp_1->status != NCI_STATUS_OK)
+ return;
+
+ ndev->nfcc_features = __le32_to_cpu(rsp_1->nfcc_features);
+ ndev->num_supported_rf_interfaces = rsp_1->num_supported_rf_interfaces;
+
+ if (ndev->num_supported_rf_interfaces >
+ NCI_MAX_SUPPORTED_RF_INTERFACES) {
+ ndev->num_supported_rf_interfaces =
+ NCI_MAX_SUPPORTED_RF_INTERFACES;
+ }
+
+ memcpy(ndev->supported_rf_interfaces,
+ rsp_1->supported_rf_interfaces,
+ ndev->num_supported_rf_interfaces);
+
+ rsp_2 = (void *) (skb->data + 6 + ndev->num_supported_rf_interfaces);
+
+ ndev->max_logical_connections =
+ rsp_2->max_logical_connections;
+ ndev->max_routing_table_size =
+ __le16_to_cpu(rsp_2->max_routing_table_size);
+ ndev->max_control_packet_payload_length =
+ rsp_2->max_control_packet_payload_length;
+ ndev->rf_sending_buffer_size =
+ __le16_to_cpu(rsp_2->rf_sending_buffer_size);
+ ndev->rf_receiving_buffer_size =
+ __le16_to_cpu(rsp_2->rf_receiving_buffer_size);
+ ndev->manufacturer_id =
+ __le16_to_cpu(rsp_2->manufacturer_id);
+
+ nfc_dbg("nfcc_features 0x%x",
+ ndev->nfcc_features);
+ nfc_dbg("num_supported_rf_interfaces %d",
+ ndev->num_supported_rf_interfaces);
+ nfc_dbg("supported_rf_interfaces[0] 0x%x",
+ ndev->supported_rf_interfaces[0]);
+ nfc_dbg("supported_rf_interfaces[1] 0x%x",
+ ndev->supported_rf_interfaces[1]);
+ nfc_dbg("supported_rf_interfaces[2] 0x%x",
+ ndev->supported_rf_interfaces[2]);
+ nfc_dbg("supported_rf_interfaces[3] 0x%x",
+ ndev->supported_rf_interfaces[3]);
+ nfc_dbg("max_logical_connections %d",
+ ndev->max_logical_connections);
+ nfc_dbg("max_routing_table_size %d",
+ ndev->max_routing_table_size);
+ nfc_dbg("max_control_packet_payload_length %d",
+ ndev->max_control_packet_payload_length);
+ nfc_dbg("rf_sending_buffer_size %d",
+ ndev->rf_sending_buffer_size);
+ nfc_dbg("rf_receiving_buffer_size %d",
+ ndev->rf_receiving_buffer_size);
+ nfc_dbg("manufacturer_id 0x%x",
+ ndev->manufacturer_id);
+
+ nci_req_complete(ndev, rsp_1->status);
+}
+
+static void nci_core_conn_create_rsp_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ struct nci_core_conn_create_rsp *rsp = (void *) skb->data;
+
+ nfc_dbg("entry, status 0x%x", rsp->status);
+
+ if (rsp->status != NCI_STATUS_OK)
+ return;
+
+ ndev->max_pkt_payload_size = rsp->max_pkt_payload_size;
+ ndev->initial_num_credits = rsp->initial_num_credits;
+ ndev->conn_id = rsp->conn_id;
+
+ atomic_set(&ndev->credits_cnt, ndev->initial_num_credits);
+
+ nfc_dbg("max_pkt_payload_size %d", ndev->max_pkt_payload_size);
+ nfc_dbg("initial_num_credits %d", ndev->initial_num_credits);
+ nfc_dbg("conn_id %d", ndev->conn_id);
+}
+
+static void nci_rf_disc_map_rsp_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ __u8 status = skb->data[0];
+
+ nfc_dbg("entry, status 0x%x", status);
+
+ nci_req_complete(ndev, status);
+}
+
+static void nci_rf_disc_rsp_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ __u8 status = skb->data[0];
+
+ nfc_dbg("entry, status 0x%x", status);
+
+ if (status == NCI_STATUS_OK)
+ set_bit(NCI_DISCOVERY, &ndev->flags);
+
+ nci_req_complete(ndev, status);
+}
+
+static void nci_rf_deactivate_rsp_packet(struct nci_dev *ndev,
+ struct sk_buff *skb)
+{
+ __u8 status = skb->data[0];
+
+ nfc_dbg("entry, status 0x%x", status);
+
+ clear_bit(NCI_DISCOVERY, &ndev->flags);
+
+ nci_req_complete(ndev, status);
+}
+
+void nci_rsp_packet(struct nci_dev *ndev, struct sk_buff *skb)
+{
+ __u16 rsp_opcode = nci_opcode(skb->data);
+
+ /* we got a rsp, stop the cmd timer */
+ del_timer(&ndev->cmd_timer);
+
+ nfc_dbg("NCI RX: MT=rsp, PBF=%d, GID=0x%x, OID=0x%x, plen=%d",
+ nci_pbf(skb->data),
+ nci_opcode_gid(rsp_opcode),
+ nci_opcode_oid(rsp_opcode),
+ nci_plen(skb->data));
+
+ /* strip the nci control header */
+ skb_pull(skb, NCI_CTRL_HDR_SIZE);
+
+ switch (rsp_opcode) {
+ case NCI_OP_CORE_RESET_RSP:
+ nci_core_reset_rsp_packet(ndev, skb);
+ break;
+
+ case NCI_OP_CORE_INIT_RSP:
+ nci_core_init_rsp_packet(ndev, skb);
+ break;
+
+ case NCI_OP_CORE_CONN_CREATE_RSP:
+ nci_core_conn_create_rsp_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_DISCOVER_MAP_RSP:
+ nci_rf_disc_map_rsp_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_DISCOVER_RSP:
+ nci_rf_disc_rsp_packet(ndev, skb);
+ break;
+
+ case NCI_OP_RF_DEACTIVATE_RSP:
+ nci_rf_deactivate_rsp_packet(ndev, skb);
+ break;
+
+ default:
+ nfc_err("unknown rsp opcode 0x%x", rsp_opcode);
+ break;
+ }
+
+ kfree_skb(skb);
+
+ /* trigger the next cmd */
+ atomic_set(&ndev->cmd_cnt, 1);
+ if (!skb_queue_empty(&ndev->cmd_q))
+ tasklet_schedule(&ndev->cmd_task);
+}
--
1.7.0.4


2011-08-18 16:11:32

by Samuel Ortiz

[permalink] [raw]
Subject: Re: [PATCH 3/4] NFC: Basic NFC NCI protocol implementation

Hi Ilan,

On Tue, 2011-08-16 at 19:36 +0200, Elias, Ilan wrote:
> The NFC Controller Interface (NCI) is a standard communication protocol between an NFC Controller (NFCC) and a Device Host (DH), defined by the NFC Forum.
>
> Signed-off-by: Ilan Elias <[email protected]>
> ---
> include/net/nfc/nci.h | 313 ++++++++++++++++++
> include/net/nfc/nci_core.h | 177 +++++++++++
> net/nfc/Kconfig | 2 +
> net/nfc/Makefile | 1 +
> net/nfc/nci/Kconfig | 10 +
> net/nfc/nci/Makefile | 7 +
> net/nfc/nci/nci_core.c | 750 ++++++++++++++++++++++++++++++++++++++++++++
> net/nfc/nci/nci_data.c | 252 +++++++++++++++
> net/nfc/nci/nci_lib.c | 94 ++++++
> net/nfc/nci/nci_ntf.c | 264 ++++++++++++++++
> net/nfc/nci/nci_rsp.c | 226 +++++++++++++
> 11 files changed, 2096 insertions(+), 0 deletions(-)
> create mode 100644 include/net/nfc/nci.h
> create mode 100644 include/net/nfc/nci_core.h
> create mode 100644 net/nfc/nci/Kconfig
> create mode 100644 net/nfc/nci/Makefile
> create mode 100644 net/nfc/nci/nci_core.c
> create mode 100644 net/nfc/nci/nci_data.c
> create mode 100644 net/nfc/nci/nci_lib.c
> create mode 100644 net/nfc/nci/nci_ntf.c
> create mode 100644 net/nfc/nci/nci_rsp.c
In general, I prefer the nci/core.c, nci/data.c, etc naming scheme as opposed to the more redundant one you're using here.

> +/* NCI Discovery Types */
> +#define NCI_DISCOVERY_TYPE_POLL_A_PASSIVE 0x00
Identation fix.


> +#define NCI_DISCOVERY_TYPE_POLL_B_PASSIVE 0x01
> +#define NCI_DISCOVERY_TYPE_POLL_F_PASSIVE 0x02
> +#define NCI_DISCOVERY_TYPE_POLL_A_ACTIVE 0x03
> +#define NCI_DISCOVERY_TYPE_POLL_F_ACTIVE 0x05
> +#define NCI_DISCOVERY_TYPE_WAKEUP_A_PASSIVE 0x06
> +#define NCI_DISCOVERY_TYPE_WAKEUP_B_PASSIVE 0x07
> +#define NCI_DISCOVERY_TYPE_WAKEUP_A_ACTIVE 0x09
> +#define NCI_DISCOVERY_TYPE_LISTEN_A_PASSIVE 0x80
> +#define NCI_DISCOVERY_TYPE_LISTEN_B_PASSIVE 0x81
> +#define NCI_DISCOVERY_TYPE_LISTEN_F_PASSIVE 0x82
> +#define NCI_DISCOVERY_TYPE_LISTEN_A_ACTIVE 0x83
> +#define NCI_DISCOVERY_TYPE_LISTEN_F_ACTIVE 0x85

> +#define NCI_MT_DATA_PKT 0x00
Ditto.

> +#define NCI_MT_CMD_PKT 0x01
> +#define NCI_MT_RSP_PKT 0x02
> +#define NCI_MT_NTF_PKT 0x03

> +/* Reserved for drivers usage */
> +#define NCI_SKB_RESERVE 4
Do we expect all drivers to need at most 4 bytes ?

> +#define nci_req_lock(ndev) mutex_lock(&ndev->req_lock)
> +#define nci_req_unlock(ndev) mutex_unlock(&ndev->req_lock)
This kind of abstraction doesn't bring much to the table. I'd prefer to
use the mutex API directly.



> +/* 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)
> +{
> + DECLARE_WAITQUEUE(wait, current);
> + int rc = 0;
> +
> + ndev->req_status = NCI_REQ_PEND;
> +
> + add_wait_queue(&ndev->req_wait_q, &wait);
> + set_current_state(TASK_INTERRUPTIBLE);
> +
> + req(ndev, opt);
> + schedule_timeout(timeout);
> +
> + remove_wait_queue(&ndev->req_wait_q, &wait);
> +
> + if (signal_pending(current))
> + return -EINTR;
> +
> + 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;
> + }
> +
> + ndev->req_status = ndev->req_result = 0;
> +
> + return rc;
> +}
So here, I wonder: Can't we just use simple completion and the
wait_for_completion_* APIs ? One completion structure per ndev and you
should be fine. Especially since you seem to be serializing (as
expected) the requests below.


> +/* 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;
> +
> + nfc_dbg("entry, opcode 0x%x, plen %d", opcode, plen);
> +
> + skb = nci_skb_alloc((NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
> + if (!skb) {
> + nfc_err("no memory for command");
> + 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);
> + tasklet_schedule(&ndev->cmd_task);
> +
> + return 0;
> +}
So I have 2 comments on this one:

1) Do we have a compelling reason for deferring the command queue
handling ? In which case can you queue a command while the previous one
is not completed yet ?
2) If we do, we certainly don't want a tasklet for that. Using a tasklet
puts some additional constraints on what we can call for it, the
tradeoff being a supposedly lower latency. I don't think we need it,
workqueues (for cmd, tx and rx) would be just fine.




> +/* Send NCI data */
> +int nci_send_data(struct nci_dev *ndev, __u8 conn_id, struct sk_buff *skb)
> +{
> + int rc = 0;
> +
> + nfc_dbg("entry, conn_id 0x%x, plen %d", conn_id, skb->len);
> +
> + /* check if the packet need to be fragmented */
> + if (skb->len <= ndev->max_pkt_payload_size) {
> + /* no need to fragment packet */
> +
> + /* reserve header space for nci and driver */
> + if (skb_cow_head(skb, (NCI_DATA_HDR_SIZE + NCI_SKB_RESERVE))) {
I think this kind of reallocations could be avoided with a couple
patches that I will post soon. We could basically tell the NFC core in
advance which head room we need.
See
http://git.kernel.org/?p=linux/kernel/git/sameo/nfc-2.6.git;a=commit;h=ba108daaec65f5d02daaf9084fa5f8f2375d0d92

Cheers,
Samuel.


2011-09-08 08:26:47

by Elias, Ilan

[permalink] [raw]
Subject: RE: [PATCH 3/4] NFC: Basic NFC NCI protocol implementation

Hi Samuel,

Thanks for your review.

> > include/net/nfc/nci.h | 313 ++++++++++++++++++
> > include/net/nfc/nci_core.h | 177 +++++++++++
> > net/nfc/Kconfig | 2 +
> > net/nfc/Makefile | 1 +
> > net/nfc/nci/Kconfig | 10 +
> > net/nfc/nci/Makefile | 7 +
> > net/nfc/nci/nci_core.c | 750
> ++++++++++++++++++++++++++++++++++++++++++++
> > net/nfc/nci/nci_data.c | 252 +++++++++++++++
> > net/nfc/nci/nci_lib.c | 94 ++++++
> > net/nfc/nci/nci_ntf.c | 264 ++++++++++++++++
> > net/nfc/nci/nci_rsp.c | 226 +++++++++++++
> > 11 files changed, 2096 insertions(+), 0 deletions(-)
> > create mode 100644 include/net/nfc/nci.h
> > create mode 100644 include/net/nfc/nci_core.h
> > create mode 100644 net/nfc/nci/Kconfig
> > create mode 100644 net/nfc/nci/Makefile
> > create mode 100644 net/nfc/nci/nci_core.c
> > create mode 100644 net/nfc/nci/nci_data.c
> > create mode 100644 net/nfc/nci/nci_lib.c
> > create mode 100644 net/nfc/nci/nci_ntf.c
> > create mode 100644 net/nfc/nci/nci_rsp.c
> In general, I prefer the nci/core.c, nci/data.c, etc naming
> scheme as opposed to the more redundant one you're using here.
OK, no problem.

>
> > +/* NCI Discovery Types */
> > +#define NCI_DISCOVERY_TYPE_POLL_A_PASSIVE 0x00
> Identation fix.
OK.

> > +#define NCI_DISCOVERY_TYPE_POLL_B_PASSIVE 0x01
> > +#define NCI_DISCOVERY_TYPE_POLL_F_PASSIVE 0x02
> > +#define NCI_DISCOVERY_TYPE_POLL_A_ACTIVE 0x03
> > +#define NCI_DISCOVERY_TYPE_POLL_F_ACTIVE 0x05
> > +#define NCI_DISCOVERY_TYPE_WAKEUP_A_PASSIVE 0x06
> > +#define NCI_DISCOVERY_TYPE_WAKEUP_B_PASSIVE 0x07
> > +#define NCI_DISCOVERY_TYPE_WAKEUP_A_ACTIVE 0x09
> > +#define NCI_DISCOVERY_TYPE_LISTEN_A_PASSIVE 0x80
> > +#define NCI_DISCOVERY_TYPE_LISTEN_B_PASSIVE 0x81
> > +#define NCI_DISCOVERY_TYPE_LISTEN_F_PASSIVE 0x82
> > +#define NCI_DISCOVERY_TYPE_LISTEN_A_ACTIVE 0x83
> > +#define NCI_DISCOVERY_TYPE_LISTEN_F_ACTIVE 0x85
>
> > +#define NCI_MT_DATA_PKT 0x00
> Ditto.
OK.

> > +#define NCI_MT_CMD_PKT 0x01
> > +#define NCI_MT_RSP_PKT 0x02
> > +#define NCI_MT_NTF_PKT 0x03
>
> > +/* Reserved for drivers usage */
> > +#define NCI_SKB_RESERVE 4
> Do we expect all drivers to need at most 4 bytes ?
I'll use the same mechanism you used in nfc_allocate_device, and pass the required
tx head and tail room for the drivers in nci_allocate_device.

> > +#define nci_req_lock(ndev) mutex_lock(&ndev->req_lock)
> > +#define nci_req_unlock(ndev)
> mutex_unlock(&ndev->req_lock)
> This kind of abstraction doesn't bring much to the table. I'd
> prefer to
> use the mutex API directly.
OK, no problem.

> > +/* 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)
> > +{
> > + DECLARE_WAITQUEUE(wait, current);
> > + int rc = 0;
> > +
> > + ndev->req_status = NCI_REQ_PEND;
> > +
> > + add_wait_queue(&ndev->req_wait_q, &wait);
> > + set_current_state(TASK_INTERRUPTIBLE);
> > +
> > + req(ndev, opt);
> > + schedule_timeout(timeout);
> > +
> > + remove_wait_queue(&ndev->req_wait_q, &wait);
> > +
> > + if (signal_pending(current))
> > + return -EINTR;
> > +
> > + 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;
> > + }
> > +
> > + ndev->req_status = ndev->req_result = 0;
> > +
> > + return rc;
> > +}
> So here, I wonder: Can't we just use simple completion and the
> wait_for_completion_* APIs ? One completion structure per ndev and you
> should be fine. Especially since you seem to be serializing (as
> expected) the requests below.
OK, I'll use completion mechanism instead of a wait queue.

> > +/* 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;
> > +
> > + nfc_dbg("entry, opcode 0x%x, plen %d", opcode, plen);
> > +
> > + skb = nci_skb_alloc((NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
> > + if (!skb) {
> > + nfc_err("no memory for command");
> > + 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);
> > + tasklet_schedule(&ndev->cmd_task);
> > +
> > + return 0;
> > +}
> So I have 2 comments on this one:
>
> 1) Do we have a compelling reason for deferring the command queue
> handling ? In which case can you queue a command while the
> previous one
> is not completed yet ?
We do, since we will need to send cmds from several possible contexts
(e.g. user context, RX context) and I don't want to delay other contexts
(e.g. RX context). In addition, I would prefer that sending cmd will always
run in the same context (e.g. the same tasklet or workqueue) in order to
simplify things.

We should be able to send several commands, while the first one is not
completed yet.
You can see an example in nci_core (nci_init_complete_req function),
where during init sequence we queue CORE_CONN_CREATE_CMD for creating
the static RF connection and RF_DISCOVER_MAP_CMD for setting the
mapping configurations.
Since this is just a preliminary implementation of the NCI, I'm certain we'll
have many more examples for queueing several commands together.

> 2) If we do, we certainly don't want a tasklet for that.
> Using a tasklet
> puts some additional constraints on what we can call for it, the
> tradeoff being a supposedly lower latency. I don't think we need it,
> workqueues (for cmd, tx and rx) would be just fine.
Sure, I can use workqueues for cmd/tx/rx instead of tasklets.

>
> > +/* Send NCI data */
> > +int nci_send_data(struct nci_dev *ndev, __u8 conn_id,
> struct sk_buff *skb)
> > +{
> > + int rc = 0;
> > +
> > + nfc_dbg("entry, conn_id 0x%x, plen %d", conn_id, skb->len);
> > +
> > + /* check if the packet need to be fragmented */
> > + if (skb->len <= ndev->max_pkt_payload_size) {
> > + /* no need to fragment packet */
> > +
> > + /* reserve header space for nci and driver */
> > + if (skb_cow_head(skb, (NCI_DATA_HDR_SIZE +
> NCI_SKB_RESERVE))) {
> I think this kind of reallocations could be avoided with a couple
> patches that I will post soon. We could basically tell the NFC core in
> advance which head room we need.
OK, I'll use the new mechanism you created.

Thanks & BR,
Ilan