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  *
 131  * @switch_rf: Turns device radio on or off. The stack does not call explicitly
 132  *      switch_rf to turn the radio on. A call to in|tg_configure_hw must turn
 133  *      the device radio on.
 134  * @abort_cmd: Discard the last sent command.
 135  *
 136  * Notes: Asynchronous functions have a timeout parameter. It is the driver
 137  *      responsibility to call the digital stack back through the
 138  *      nfc_digital_cmd_complete_t callback when no RF respsonse has been
 139  *      received within the specified time (in milliseconds). In that case the
 140  *      driver must set the resp sk_buff to ERR_PTR(-ETIMEDOUT).
 141  *      Since the digital stack serializes commands to be sent, it's mandatory
 142  *      for the driver to handle the timeout correctly. Otherwise the stack
 143  *      would not be able to send new commands, waiting for the reply of the
 144  *      current one.
 145  */
 146 struct nfc_digital_ops {
 147         int (*in_configure_hw)(struct nfc_digital_dev *ddev, int type,
 148                                int param);
 149         int (*in_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 150                            u16 timeout, nfc_digital_cmd_complete_t cb,
 151                            void *arg);
 152
 153         int (*tg_configure_hw)(struct nfc_digital_dev *ddev, int type,
 154                                int param);
 155         int (*tg_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 156                            u16 timeout, nfc_digital_cmd_complete_t cb,
 157                            void *arg);
 158         int (*tg_listen)(struct nfc_digital_dev *ddev, u16 timeout,
 159                          nfc_digital_cmd_complete_t cb, void *arg);
 160         int (*tg_listen_mdaa)(struct nfc_digital_dev *ddev,
 161                               struct digital_tg_mdaa_params *mdaa_params,
 162                               u16 timeout, nfc_digital_cmd_complete_t cb,
 163                               void *arg);
 164
 165         int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
 166         void (*abort_cmd)(struct nfc_digital_dev *ddev);
 167 };
 168
 169 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX 6 /* 106A, 212F, and 424F in & tg */
 170
 171 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
 172
 173 struct digital_poll_tech {
 174         u8 rf_tech;
 175         digital_poll_t poll_func;
 176 };
 177
 178 /**
 179  * Driver capabilities - bit mask made of the following values
 180  *
 181  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
 182  *      mode.
 183  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
 184  *      mode.
 185  */
 186 #define NFC_DIGITAL_DRV_CAPS_IN_CRC     0x0001
 187 #define NFC_DIGITAL_DRV_CAPS_TG_CRC     0x0002
 188
 189 struct nfc_digital_dev {
 190         struct nfc_dev *nfc_dev;
 191         struct nfc_digital_ops *ops;
 192
 193         u32 protocols;
 194
 195         int tx_headroom;
 196         int tx_tailroom;
 197
 198         u32 driver_capabilities;
 199         void *driver_data;
 200
 201         struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
 202         u8 poll_tech_count;
 203         u8 poll_tech_index;
 204         struct mutex poll_lock;
 205
 206         struct work_struct cmd_work;
 207         struct work_struct cmd_complete_work;
 208         struct list_head cmd_queue;
 209         struct mutex cmd_lock;
 210
 211         struct work_struct poll_work;
 212
 213         u8 curr_protocol;
 214         u8 curr_rf_tech;
 215         u8 curr_nfc_dep_pni;
 216
 217         u16 target_fsc;
 218
 219         int (*skb_check_crc)(struct sk_buff *skb);
 220         void (*skb_add_crc)(struct sk_buff *skb);
 221 };
 222
 223 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
 224                                                     __u32 supported_protocols,
 225                                                     __u32 driver_capabilities,
 226                                                     int tx_headroom,
 227                                                     int tx_tailroom);
 228 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
 229 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
 230 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
 231
 232 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
 233                                               struct device *dev)
 234 {
 235         nfc_set_parent_dev(ndev->nfc_dev, dev);
 236 }
 237
 238 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
 239                                            void *data)
 240 {
 241         dev->driver_data = data;
 242 }
 243
 244 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
 245 {
 246         return dev->driver_data;
 247 }
 248
 249 #endif /* __NFC_DIGITAL_H */