xref: /openbmc/linux/include/net/nfc/digital.h (revision d2999e1b)
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 
53 	NFC_DIGITAL_FRAMING_NFCA_T1T,
54 	NFC_DIGITAL_FRAMING_NFCA_T2T,
55 	NFC_DIGITAL_FRAMING_NFCA_T4T,
56 	NFC_DIGITAL_FRAMING_NFCA_NFC_DEP,
57 
58 	NFC_DIGITAL_FRAMING_NFCF,
59 	NFC_DIGITAL_FRAMING_NFCF_T3T,
60 	NFC_DIGITAL_FRAMING_NFCF_NFC_DEP,
61 	NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED,
62 
63 	NFC_DIGITAL_FRAMING_ISO15693_INVENTORY,
64 	NFC_DIGITAL_FRAMING_ISO15693_T5T,
65 
66 	NFC_DIGITAL_FRAMING_NFCB,
67 	NFC_DIGITAL_FRAMING_NFCB_T4T,
68 
69 	NFC_DIGITAL_FRAMING_LAST,
70 };
71 
72 #define DIGITAL_MDAA_NFCID1_SIZE 3
73 
74 struct digital_tg_mdaa_params {
75 	u16 sens_res;
76 	u8 nfcid1[DIGITAL_MDAA_NFCID1_SIZE];
77 	u8 sel_res;
78 
79 	u8 nfcid2[NFC_NFCID2_MAXSIZE];
80 	u16 sc;
81 };
82 
83 struct nfc_digital_dev;
84 
85 /**
86  * nfc_digital_cmd_complete_t - Definition of command result callback
87  *
88  * @ddev: nfc_digital_device ref
89  * @arg: user data
90  * @resp: response data
91  *
92  * resp pointer can be an error code and will be checked with IS_ERR() macro.
93  * The callback is responsible for freeing resp sk_buff.
94  */
95 typedef void (*nfc_digital_cmd_complete_t)(struct nfc_digital_dev *ddev,
96 					   void *arg, struct sk_buff *resp);
97 
98 /**
99  * Device side NFC Digital operations
100  *
101  * Initiator mode:
102  * @in_configure_hw: Hardware configuration for RF technology and communication
103  *	framing in initiator mode. This is a synchronous function.
104  * @in_send_cmd: Initiator mode data exchange using RF technology and framing
105  *	previously set with in_configure_hw. The peer response is returned
106  *	through callback cb. If an io error occurs or the peer didn't reply
107  *	within the specified timeout (ms), the error code is passed back through
108  *	the resp pointer. This is an asynchronous function.
109  *
110  * Target mode: Only NFC-DEP protocol is supported in target mode.
111  * @tg_configure_hw: Hardware configuration for RF technology and communication
112  *	framing in target mode. This is a synchronous function.
113  * @tg_send_cmd: Target mode data exchange using RF technology and framing
114  *	previously set with tg_configure_hw. The peer next command is returned
115  *	through callback cb. If an io error occurs or the peer didn't reply
116  *	within the specified timeout (ms), the error code is passed back through
117  *	the resp pointer. This is an asynchronous function.
118  * @tg_listen: Put the device in listen mode waiting for data from the peer
119  *	device. This is an asynchronous function.
120  * @tg_listen_mdaa: If supported, put the device in automatic listen mode with
121  *	mode detection and automatic anti-collision. In this mode, the device
122  *	automatically detects the RF technology and executes the anti-collision
123  *	detection using the command responses specified in mdaa_params. The
124  *	mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF
125  *	tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns
126  *	the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF
127  *	tech by analyzing the SoD of the frame containing the ATR_REQ command.
128  *	This is an asynchronous function.
129  *
130  * @switch_rf: Turns device radio on or off. The stack does not call explicitly
131  *	switch_rf to turn the radio on. A call to in|tg_configure_hw must turn
132  *	the device radio on.
133  * @abort_cmd: Discard the last sent command.
134  *
135  * Notes: Asynchronous functions have a timeout parameter. It is the driver
136  *	responsibility to call the digital stack back through the
137  *	nfc_digital_cmd_complete_t callback when no RF respsonse has been
138  *	received within the specified time (in milliseconds). In that case the
139  *	driver must set the resp sk_buff to ERR_PTR(-ETIMEDOUT).
140  *	Since the digital stack serializes commands to be sent, it's mandatory
141  *	for the driver to handle the timeout correctly. Otherwise the stack
142  *	would not be able to send new commands, waiting for the reply of the
143  *	current one.
144  */
145 struct nfc_digital_ops {
146 	int (*in_configure_hw)(struct nfc_digital_dev *ddev, int type,
147 			       int param);
148 	int (*in_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
149 			   u16 timeout, nfc_digital_cmd_complete_t cb,
150 			   void *arg);
151 
152 	int (*tg_configure_hw)(struct nfc_digital_dev *ddev, int type,
153 			       int param);
154 	int (*tg_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
155 			   u16 timeout, nfc_digital_cmd_complete_t cb,
156 			   void *arg);
157 	int (*tg_listen)(struct nfc_digital_dev *ddev, u16 timeout,
158 			 nfc_digital_cmd_complete_t cb, void *arg);
159 	int (*tg_listen_mdaa)(struct nfc_digital_dev *ddev,
160 			      struct digital_tg_mdaa_params *mdaa_params,
161 			      u16 timeout, nfc_digital_cmd_complete_t cb,
162 			      void *arg);
163 
164 	int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
165 	void (*abort_cmd)(struct nfc_digital_dev *ddev);
166 };
167 
168 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX	6 /* 106A, 212F, and 424F in & tg */
169 
170 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
171 
172 struct digital_poll_tech {
173 	u8 rf_tech;
174 	digital_poll_t poll_func;
175 };
176 
177 /**
178  * Driver capabilities - bit mask made of the following values
179  *
180  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
181  *	mode.
182  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
183  *	mode.
184  */
185 #define NFC_DIGITAL_DRV_CAPS_IN_CRC	0x0001
186 #define NFC_DIGITAL_DRV_CAPS_TG_CRC	0x0002
187 
188 struct nfc_digital_dev {
189 	struct nfc_dev *nfc_dev;
190 	struct nfc_digital_ops *ops;
191 
192 	u32 protocols;
193 
194 	int tx_headroom;
195 	int tx_tailroom;
196 
197 	u32 driver_capabilities;
198 	void *driver_data;
199 
200 	struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
201 	u8 poll_tech_count;
202 	u8 poll_tech_index;
203 	struct mutex poll_lock;
204 
205 	struct work_struct cmd_work;
206 	struct work_struct cmd_complete_work;
207 	struct list_head cmd_queue;
208 	struct mutex cmd_lock;
209 
210 	struct work_struct poll_work;
211 
212 	u8 curr_protocol;
213 	u8 curr_rf_tech;
214 	u8 curr_nfc_dep_pni;
215 
216 	u16 target_fsc;
217 
218 	int (*skb_check_crc)(struct sk_buff *skb);
219 	void (*skb_add_crc)(struct sk_buff *skb);
220 };
221 
222 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
223 						    __u32 supported_protocols,
224 						    __u32 driver_capabilities,
225 						    int tx_headroom,
226 						    int tx_tailroom);
227 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
228 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
229 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
230 
231 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
232 					      struct device *dev)
233 {
234 	nfc_set_parent_dev(ndev->nfc_dev, dev);
235 }
236 
237 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
238 					   void *data)
239 {
240 	dev->driver_data = data;
241 }
242 
243 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
244 {
245 	return dev->driver_data;
246 }
247 
248 #endif /* __NFC_DIGITAL_H */
249