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 const 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(const 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
nfc_digital_set_parent_dev(struct nfc_digital_dev * ndev,struct device * dev)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
nfc_digital_set_drvdata(struct nfc_digital_dev * dev,void * data)254 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
255 void *data)
256 {
257 dev->driver_data = data;
258 }
259
nfc_digital_get_drvdata(struct nfc_digital_dev * dev)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 */
266