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
nfc_digital_set_parent_dev(struct nfc_digital_dev * ndev,struct device * dev)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
nfc_digital_set_drvdata(struct nfc_digital_dev * dev,void * data)263 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
264 void *data)
265 {
266 dev->driver_data = data;
267 }
268
nfc_digital_get_drvdata(struct nfc_digital_dev * dev)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 */
275