include/net/nfc/digital.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * NFC Digital Protocol stack
   4  * Copyright (c) 2013, Intel Corporation.
   5  */
   6
   7 #ifndef __NFC_DIGITAL_H
   8 #define __NFC_DIGITAL_H
   9
  10 #include <linux/skbuff.h>
  11 #include <net/nfc/nfc.h>
  12
  13 /**
  14  * Configuration types for in_configure_hw and tg_configure_hw.
  15  */
  16 enum {
  17         NFC_DIGITAL_CONFIG_RF_TECH = 0,
  18         NFC_DIGITAL_CONFIG_FRAMING,
  19 };
  20
  21 /**
  22  * RF technology values passed as param argument to in_configure_hw and
  23  * tg_configure_hw for NFC_DIGITAL_CONFIG_RF_TECH configuration type.
  24  */
  25 enum {
  26         NFC_DIGITAL_RF_TECH_106A = 0,
  27         NFC_DIGITAL_RF_TECH_212F,
  28         NFC_DIGITAL_RF_TECH_424F,
  29         NFC_DIGITAL_RF_TECH_ISO15693,
  30         NFC_DIGITAL_RF_TECH_106B,
  31
  32         NFC_DIGITAL_RF_TECH_LAST,
  33 };
  34
  35 /**
  36  * Framing configuration passed as param argument to in_configure_hw and
  37  * tg_configure_hw for NFC_DIGITAL_CONFIG_FRAMING configuration type.
  38  */
  39 enum {
  40         NFC_DIGITAL_FRAMING_NFCA_SHORT = 0,
  41         NFC_DIGITAL_FRAMING_NFCA_STANDARD,
  42         NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A,
  43         NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE,
  44
  45         NFC_DIGITAL_FRAMING_NFCA_T1T,
  46         NFC_DIGITAL_FRAMING_NFCA_T2T,
  47         NFC_DIGITAL_FRAMING_NFCA_T4T,
  48         NFC_DIGITAL_FRAMING_NFCA_NFC_DEP,
  49
  50         NFC_DIGITAL_FRAMING_NFCF,
  51         NFC_DIGITAL_FRAMING_NFCF_T3T,
  52         NFC_DIGITAL_FRAMING_NFCF_NFC_DEP,
  53         NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED,
  54
  55         NFC_DIGITAL_FRAMING_ISO15693_INVENTORY,
  56         NFC_DIGITAL_FRAMING_ISO15693_T5T,
  57
  58         NFC_DIGITAL_FRAMING_NFCB,
  59         NFC_DIGITAL_FRAMING_NFCB_T4T,
  60
  61         NFC_DIGITAL_FRAMING_LAST,
  62 };
  63
  64 #define DIGITAL_MDAA_NFCID1_SIZE 3
  65
  66 struct digital_tg_mdaa_params {
  67         u16 sens_res;
  68         u8 nfcid1[DIGITAL_MDAA_NFCID1_SIZE];
  69         u8 sel_res;
  70
  71         u8 nfcid2[NFC_NFCID2_MAXSIZE];
  72         u16 sc;
  73 };
  74
  75 struct nfc_digital_dev;
  76
  77 /**
  78  * nfc_digital_cmd_complete_t - Definition of command result callback
  79  *
  80  * @ddev: nfc_digital_device ref
  81  * @arg: user data
  82  * @resp: response data
  83  *
  84  * resp pointer can be an error code and will be checked with IS_ERR() macro.
  85  * The callback is responsible for freeing resp sk_buff.
  86  */
  87 typedef void (*nfc_digital_cmd_complete_t)(struct nfc_digital_dev *ddev,
  88                                            void *arg, struct sk_buff *resp);
  89
  90 /**
  91  * Device side NFC Digital operations
  92  *
  93  * Initiator mode:
  94  * @in_configure_hw: Hardware configuration for RF technology and communication
  95  *      framing in initiator mode. This is a synchronous function.
  96  * @in_send_cmd: Initiator mode data exchange using RF technology and framing
  97  *      previously set with in_configure_hw. The peer response is returned
  98  *      through callback cb. If an io error occurs or the peer didn't reply
  99  *      within the specified timeout (ms), the error code is passed back through
 100  *      the resp pointer. This is an asynchronous function.
 101  *
 102  * Target mode: Only NFC-DEP protocol is supported in target mode.
 103  * @tg_configure_hw: Hardware configuration for RF technology and communication
 104  *      framing in target mode. This is a synchronous function.
 105  * @tg_send_cmd: Target mode data exchange using RF technology and framing
 106  *      previously set with tg_configure_hw. The peer next command 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  * @tg_listen: Put the device in listen mode waiting for data from the peer
 111  *      device. This is an asynchronous function.
 112  * @tg_listen_mdaa: If supported, put the device in automatic listen mode with
 113  *      mode detection and automatic anti-collision. In this mode, the device
 114  *      automatically detects the RF technology and executes the anti-collision
 115  *      detection using the command responses specified in mdaa_params. The
 116  *      mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF
 117  *      tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns
 118  *      the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF
 119  *      tech by analyzing the SoD of the frame containing the ATR_REQ command.
 120  *      This is an asynchronous function.
 121  * @tg_listen_md: If supported, put the device in automatic listen mode with
 122  *      mode detection but without automatic anti-collision. In this mode, the
 123  *      device automatically detects the RF technology.  What the actual
 124  *      RF technology is can be retrieved by calling @tg_get_rf_tech.
 125  *      The digital stack will then perform the appropriate anti-collision
 126  *      sequence.  This is an asynchronous function.
 127  * @tg_get_rf_tech: Required when @tg_listen_md is supported, unused otherwise.
 128  *      Return the RF Technology that was detected by the @tg_listen_md call.
 129  *      This is a synchronous 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         int (*tg_listen_md)(struct nfc_digital_dev *ddev, u16 timeout,
 165                             nfc_digital_cmd_complete_t cb, void *arg);
 166         int (*tg_get_rf_tech)(struct nfc_digital_dev *ddev, u8 *rf_tech);
 167
 168         int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
 169         void (*abort_cmd)(struct nfc_digital_dev *ddev);
 170 };
 171
 172 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX 6 /* 106A, 212F, and 424F in & tg */
 173
 174 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
 175
 176 struct digital_poll_tech {
 177         u8 rf_tech;
 178         digital_poll_t poll_func;
 179 };
 180
 181 /**
 182  * Driver capabilities - bit mask made of the following values
 183  *
 184  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
 185  *      mode.
 186  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
 187  *      mode.
 188  */
 189 #define NFC_DIGITAL_DRV_CAPS_IN_CRC     0x0001
 190 #define NFC_DIGITAL_DRV_CAPS_TG_CRC     0x0002
 191
 192 struct nfc_digital_dev {
 193         struct nfc_dev *nfc_dev;
 194         struct nfc_digital_ops *ops;
 195
 196         u32 protocols;
 197
 198         int tx_headroom;
 199         int tx_tailroom;
 200
 201         u32 driver_capabilities;
 202         void *driver_data;
 203
 204         struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
 205         u8 poll_tech_count;
 206         u8 poll_tech_index;
 207         struct mutex poll_lock;
 208
 209         struct work_struct cmd_work;
 210         struct work_struct cmd_complete_work;
 211         struct list_head cmd_queue;
 212         struct mutex cmd_lock;
 213
 214         struct delayed_work poll_work;
 215
 216         u8 curr_protocol;
 217         u8 curr_rf_tech;
 218         u8 curr_nfc_dep_pni;
 219         u8 did;
 220         u16 dep_rwt;
 221
 222         u8 local_payload_max;
 223         u8 remote_payload_max;
 224
 225         struct sk_buff *chaining_skb;
 226         struct digital_data_exch *data_exch;
 227
 228         int atn_count;
 229         int nack_count;
 230
 231         struct sk_buff *saved_skb;
 232
 233         u16 target_fsc;
 234
 235         int (*skb_check_crc)(struct sk_buff *skb);
 236         void (*skb_add_crc)(struct sk_buff *skb);
 237 };
 238
 239 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
 240                                                     __u32 supported_protocols,
 241                                                     __u32 driver_capabilities,
 242                                                     int tx_headroom,
 243                                                     int tx_tailroom);
 244 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
 245 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
 246 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
 247
 248 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
 249                                               struct device *dev)
 250 {
 251         nfc_set_parent_dev(ndev->nfc_dev, dev);
 252 }
 253
 254 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
 255                                            void *data)
 256 {
 257         dev->driver_data = data;
 258 }
 259
 260 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
 261 {
 262         return dev->driver_data;
 263 }
 264
 265 #endif /* __NFC_DIGITAL_H */