include/net/nfc/digital.h

   1 /*
   2  * NFC Digital Protocol stack
   3  * Copyright (c) 2013, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  */
  15
  16 #ifndef __NFC_DIGITAL_H
  17 #define __NFC_DIGITAL_H
  18
  19 #include <linux/skbuff.h>
  20 #include <net/nfc/nfc.h>
  21
  22 /**
  23  * Configuration types for in_configure_hw and tg_configure_hw.
  24  */
  25 enum {
  26         NFC_DIGITAL_CONFIG_RF_TECH = 0,
  27         NFC_DIGITAL_CONFIG_FRAMING,
  28 };
  29
  30 /**
  31  * RF technology values passed as param argument to in_configure_hw and
  32  * tg_configure_hw for NFC_DIGITAL_CONFIG_RF_TECH configuration type.
  33  */
  34 enum {
  35         NFC_DIGITAL_RF_TECH_106A = 0,
  36         NFC_DIGITAL_RF_TECH_212F,
  37         NFC_DIGITAL_RF_TECH_424F,
  38         NFC_DIGITAL_RF_TECH_ISO15693,
  39         NFC_DIGITAL_RF_TECH_106B,
  40
  41         NFC_DIGITAL_RF_TECH_LAST,
  42 };
  43
  44 /**
  45  * Framing configuration passed as param argument to in_configure_hw and
  46  * tg_configure_hw for NFC_DIGITAL_CONFIG_FRAMING configuration type.
  47  */
  48 enum {
  49         NFC_DIGITAL_FRAMING_NFCA_SHORT = 0,
  50         NFC_DIGITAL_FRAMING_NFCA_STANDARD,
  51         NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A,
  52         NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE,
  53
  54         NFC_DIGITAL_FRAMING_NFCA_T1T,
  55         NFC_DIGITAL_FRAMING_NFCA_T2T,
  56         NFC_DIGITAL_FRAMING_NFCA_T4T,
  57         NFC_DIGITAL_FRAMING_NFCA_NFC_DEP,
  58
  59         NFC_DIGITAL_FRAMING_NFCF,
  60         NFC_DIGITAL_FRAMING_NFCF_T3T,
  61         NFC_DIGITAL_FRAMING_NFCF_NFC_DEP,
  62         NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED,
  63
  64         NFC_DIGITAL_FRAMING_ISO15693_INVENTORY,
  65         NFC_DIGITAL_FRAMING_ISO15693_T5T,
  66
  67         NFC_DIGITAL_FRAMING_NFCB,
  68         NFC_DIGITAL_FRAMING_NFCB_T4T,
  69
  70         NFC_DIGITAL_FRAMING_LAST,
  71 };
  72
  73 #define DIGITAL_MDAA_NFCID1_SIZE 3
  74
  75 struct digital_tg_mdaa_params {
  76         u16 sens_res;
  77         u8 nfcid1[DIGITAL_MDAA_NFCID1_SIZE];
  78         u8 sel_res;
  79
  80         u8 nfcid2[NFC_NFCID2_MAXSIZE];
  81         u16 sc;
  82 };
  83
  84 struct nfc_digital_dev;
  85
  86 /**
  87  * nfc_digital_cmd_complete_t - Definition of command result callback
  88  *
  89  * @ddev: nfc_digital_device ref
  90  * @arg: user data
  91  * @resp: response data
  92  *
  93  * resp pointer can be an error code and will be checked with IS_ERR() macro.
  94  * The callback is responsible for freeing resp sk_buff.
  95  */
  96 typedef void (*nfc_digital_cmd_complete_t)(struct nfc_digital_dev *ddev,
  97                                            void *arg, struct sk_buff *resp);
  98
  99 /**
 100  * Device side NFC Digital operations
 101  *
 102  * Initiator mode:
 103  * @in_configure_hw: Hardware configuration for RF technology and communication
 104  *      framing in initiator mode. This is a synchronous function.
 105  * @in_send_cmd: Initiator mode data exchange using RF technology and framing
 106  *      previously set with in_configure_hw. The peer response is returned
 107  *      through callback cb. If an io error occurs or the peer didn't reply
 108  *      within the specified timeout (ms), the error code is passed back through
 109  *      the resp pointer. This is an asynchronous function.
 110  *
 111  * Target mode: Only NFC-DEP protocol is supported in target mode.
 112  * @tg_configure_hw: Hardware configuration for RF technology and communication
 113  *      framing in target mode. This is a synchronous function.
 114  * @tg_send_cmd: Target mode data exchange using RF technology and framing
 115  *      previously set with tg_configure_hw. The peer next command is returned
 116  *      through callback cb. If an io error occurs or the peer didn't reply
 117  *      within the specified timeout (ms), the error code is passed back through
 118  *      the resp pointer. This is an asynchronous function.
 119  * @tg_listen: Put the device in listen mode waiting for data from the peer
 120  *      device. This is an asynchronous function.
 121  * @tg_listen_mdaa: If supported, put the device in automatic listen mode with
 122  *      mode detection and automatic anti-collision. In this mode, the device
 123  *      automatically detects the RF technology and executes the anti-collision
 124  *      detection using the command responses specified in mdaa_params. The
 125  *      mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF
 126  *      tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns
 127  *      the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF
 128  *      tech by analyzing the SoD of the frame containing the ATR_REQ command.
 129  *      This is an asynchronous function.
 130  * @tg_listen_md: If supported, put the device in automatic listen mode with
 131  *      mode detection but without automatic anti-collision. In this mode, the
 132  *      device automatically detects the RF technology.  What the actual
 133  *      RF technology is can be retrieved by calling @tg_get_rf_tech.
 134  *      The digital stack will then perform the appropriate anti-collision
 135  *      sequence.  This is an asynchronous function.
 136  * @tg_get_rf_tech: Required when @tg_listen_md is supported, unused otherwise.
 137  *      Return the RF Technology that was detected by the @tg_listen_md call.
 138  *      This is a synchronous function.
 139  *
 140  * @switch_rf: Turns device radio on or off. The stack does not call explicitly
 141  *      switch_rf to turn the radio on. A call to in|tg_configure_hw must turn
 142  *      the device radio on.
 143  * @abort_cmd: Discard the last sent command.
 144  *
 145  * Notes: Asynchronous functions have a timeout parameter. It is the driver
 146  *      responsibility to call the digital stack back through the
 147  *      nfc_digital_cmd_complete_t callback when no RF respsonse has been
 148  *      received within the specified time (in milliseconds). In that case the
 149  *      driver must set the resp sk_buff to ERR_PTR(-ETIMEDOUT).
 150  *      Since the digital stack serializes commands to be sent, it's mandatory
 151  *      for the driver to handle the timeout correctly. Otherwise the stack
 152  *      would not be able to send new commands, waiting for the reply of the
 153  *      current one.
 154  */
 155 struct nfc_digital_ops {
 156         int (*in_configure_hw)(struct nfc_digital_dev *ddev, int type,
 157                                int param);
 158         int (*in_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 159                            u16 timeout, nfc_digital_cmd_complete_t cb,
 160                            void *arg);
 161
 162         int (*tg_configure_hw)(struct nfc_digital_dev *ddev, int type,
 163                                int param);
 164         int (*tg_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 165                            u16 timeout, nfc_digital_cmd_complete_t cb,
 166                            void *arg);
 167         int (*tg_listen)(struct nfc_digital_dev *ddev, u16 timeout,
 168                          nfc_digital_cmd_complete_t cb, void *arg);
 169         int (*tg_listen_mdaa)(struct nfc_digital_dev *ddev,
 170                               struct digital_tg_mdaa_params *mdaa_params,
 171                               u16 timeout, nfc_digital_cmd_complete_t cb,
 172                               void *arg);
 173         int (*tg_listen_md)(struct nfc_digital_dev *ddev, u16 timeout,
 174                             nfc_digital_cmd_complete_t cb, void *arg);
 175         int (*tg_get_rf_tech)(struct nfc_digital_dev *ddev, u8 *rf_tech);
 176
 177         int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
 178         void (*abort_cmd)(struct nfc_digital_dev *ddev);
 179 };
 180
 181 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX 6 /* 106A, 212F, and 424F in & tg */
 182
 183 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
 184
 185 struct digital_poll_tech {
 186         u8 rf_tech;
 187         digital_poll_t poll_func;
 188 };
 189
 190 /**
 191  * Driver capabilities - bit mask made of the following values
 192  *
 193  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
 194  *      mode.
 195  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
 196  *      mode.
 197  */
 198 #define NFC_DIGITAL_DRV_CAPS_IN_CRC     0x0001
 199 #define NFC_DIGITAL_DRV_CAPS_TG_CRC     0x0002
 200
 201 struct nfc_digital_dev {
 202         struct nfc_dev *nfc_dev;
 203         struct nfc_digital_ops *ops;
 204
 205         u32 protocols;
 206
 207         int tx_headroom;
 208         int tx_tailroom;
 209
 210         u32 driver_capabilities;
 211         void *driver_data;
 212
 213         struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
 214         u8 poll_tech_count;
 215         u8 poll_tech_index;
 216         struct mutex poll_lock;
 217
 218         struct work_struct cmd_work;
 219         struct work_struct cmd_complete_work;
 220         struct list_head cmd_queue;
 221         struct mutex cmd_lock;
 222
 223         struct delayed_work poll_work;
 224
 225         u8 curr_protocol;
 226         u8 curr_rf_tech;
 227         u8 curr_nfc_dep_pni;
 228         u8 did;
 229         u16 dep_rwt;
 230
 231         u8 local_payload_max;
 232         u8 remote_payload_max;
 233
 234         struct sk_buff *chaining_skb;
 235         struct digital_data_exch *data_exch;
 236
 237         int atn_count;
 238         int nack_count;
 239
 240         struct sk_buff *saved_skb;
 241
 242         u16 target_fsc;
 243
 244         int (*skb_check_crc)(struct sk_buff *skb);
 245         void (*skb_add_crc)(struct sk_buff *skb);
 246 };
 247
 248 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
 249                                                     __u32 supported_protocols,
 250                                                     __u32 driver_capabilities,
 251                                                     int tx_headroom,
 252                                                     int tx_tailroom);
 253 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
 254 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
 255 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
 256
 257 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
 258                                               struct device *dev)
 259 {
 260         nfc_set_parent_dev(ndev->nfc_dev, dev);
 261 }
 262
 263 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
 264                                            void *data)
 265 {
 266         dev->driver_data = data;
 267 }
 268
 269 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
 270 {
 271         return dev->driver_data;
 272 }
 273
 274 #endif /* __NFC_DIGITAL_H */