xref: /linux/include/net/nfc/digital.h (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 
39 	NFC_DIGITAL_RF_TECH_LAST,
40 };
41 
42 /**
43  * Framing configuration passed as param argument to in_configure_hw and
44  * tg_configure_hw for NFC_DIGITAL_CONFIG_FRAMING configuration type.
45  */
46 enum {
47 	NFC_DIGITAL_FRAMING_NFCA_SHORT = 0,
48 	NFC_DIGITAL_FRAMING_NFCA_STANDARD,
49 	NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A,
50 
51 	NFC_DIGITAL_FRAMING_NFCA_T1T,
52 	NFC_DIGITAL_FRAMING_NFCA_T2T,
53 	NFC_DIGITAL_FRAMING_NFCA_NFC_DEP,
54 
55 	NFC_DIGITAL_FRAMING_NFCF,
56 	NFC_DIGITAL_FRAMING_NFCF_T3T,
57 	NFC_DIGITAL_FRAMING_NFCF_NFC_DEP,
58 	NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED,
59 
60 	NFC_DIGITAL_FRAMING_LAST,
61 };
62 
63 #define DIGITAL_MDAA_NFCID1_SIZE 3
64 
65 struct digital_tg_mdaa_params {
66 	u16 sens_res;
67 	u8 nfcid1[DIGITAL_MDAA_NFCID1_SIZE];
68 	u8 sel_res;
69 
70 	u8 nfcid2[NFC_NFCID2_MAXSIZE];
71 	u16 sc;
72 };
73 
74 struct nfc_digital_dev;
75 
76 /**
77  * nfc_digital_cmd_complete_t - Definition of command result callback
78  *
79  * @ddev: nfc_digital_device ref
80  * @arg: user data
81  * @resp: response data
82  *
83  * resp pointer can be an error code and will be checked with IS_ERR() macro.
84  * The callback is responsible for freeing resp sk_buff.
85  */
86 typedef void (*nfc_digital_cmd_complete_t)(struct nfc_digital_dev *ddev,
87 					   void *arg, struct sk_buff *resp);
88 
89 /**
90  * Device side NFC Digital operations
91  *
92  * Initiator mode:
93  * @in_configure_hw: Hardware configuration for RF technology and communication
94  *	framing in initiator mode. This is a synchronous function.
95  * @in_send_cmd: Initiator mode data exchange using RF technology and framing
96  *	previously set with in_configure_hw. The peer response is returned
97  *	through callback cb. If an io error occurs or the peer didn't reply
98  *	within the specified timeout (ms), the error code is passed back through
99  *	the resp pointer. This is an asynchronous function.
100  *
101  * Target mode: Only NFC-DEP protocol is supported in target mode.
102  * @tg_configure_hw: Hardware configuration for RF technology and communication
103  *	framing in target mode. This is a synchronous function.
104  * @tg_send_cmd: Target mode data exchange using RF technology and framing
105  *	previously set with tg_configure_hw. The peer next command 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  * @tg_listen: Put the device in listen mode waiting for data from the peer
110  *	device. This is an asynchronous function.
111  * @tg_listen_mdaa: If supported, put the device in automatic listen mode with
112  *	mode detection and automatic anti-collision. In this mode, the device
113  *	automatically detects the RF technology and executes the anti-collision
114  *	detection using the command responses specified in mdaa_params. The
115  *	mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF
116  *	tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns
117  *	the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF
118  *	tech by analyzing the SoD of the frame containing the ATR_REQ command.
119  *	This is an asynchronous function.
120  *
121  * @switch_rf: Turns device radio on or off. The stack does not call explicitly
122  *	switch_rf to turn the radio on. A call to in|tg_configure_hw must turn
123  *	the device radio on.
124  * @abort_cmd: Discard the last sent command.
125  */
126 struct nfc_digital_ops {
127 	int (*in_configure_hw)(struct nfc_digital_dev *ddev, int type,
128 			       int param);
129 	int (*in_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
130 			   u16 timeout, nfc_digital_cmd_complete_t cb,
131 			   void *arg);
132 
133 	int (*tg_configure_hw)(struct nfc_digital_dev *ddev, int type,
134 			       int param);
135 	int (*tg_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
136 			   u16 timeout, nfc_digital_cmd_complete_t cb,
137 			   void *arg);
138 	int (*tg_listen)(struct nfc_digital_dev *ddev, u16 timeout,
139 			 nfc_digital_cmd_complete_t cb, void *arg);
140 	int (*tg_listen_mdaa)(struct nfc_digital_dev *ddev,
141 			      struct digital_tg_mdaa_params *mdaa_params,
142 			      u16 timeout, nfc_digital_cmd_complete_t cb,
143 			      void *arg);
144 
145 	int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
146 	void (*abort_cmd)(struct nfc_digital_dev *ddev);
147 };
148 
149 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX	6 /* 106A, 212F, and 424F in & tg */
150 
151 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
152 
153 struct digital_poll_tech {
154 	u8 rf_tech;
155 	digital_poll_t poll_func;
156 };
157 
158 /**
159  * Driver capabilities - bit mask made of the following values
160  *
161  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
162  *	mode.
163  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
164  *	mode.
165  */
166 #define NFC_DIGITAL_DRV_CAPS_IN_CRC	0x0001
167 #define NFC_DIGITAL_DRV_CAPS_TG_CRC	0x0002
168 
169 struct nfc_digital_dev {
170 	struct nfc_dev *nfc_dev;
171 	struct nfc_digital_ops *ops;
172 
173 	u32 protocols;
174 
175 	int tx_headroom;
176 	int tx_tailroom;
177 
178 	u32 driver_capabilities;
179 	void *driver_data;
180 
181 	struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
182 	u8 poll_tech_count;
183 	u8 poll_tech_index;
184 	struct mutex poll_lock;
185 
186 	struct work_struct cmd_work;
187 	struct work_struct cmd_complete_work;
188 	struct list_head cmd_queue;
189 	struct mutex cmd_lock;
190 
191 	struct work_struct poll_work;
192 
193 	u8 curr_protocol;
194 	u8 curr_rf_tech;
195 	u8 curr_nfc_dep_pni;
196 
197 	int (*skb_check_crc)(struct sk_buff *skb);
198 	void (*skb_add_crc)(struct sk_buff *skb);
199 };
200 
201 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
202 						    __u32 supported_protocols,
203 						    __u32 driver_capabilities,
204 						    int tx_headroom,
205 						    int tx_tailroom);
206 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
207 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
208 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
209 
210 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
211 					      struct device *dev)
212 {
213 	nfc_set_parent_dev(ndev->nfc_dev, dev);
214 }
215 
216 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
217 					   void *data)
218 {
219 	dev->driver_data = data;
220 }
221 
222 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
223 {
224 	return dev->driver_data;
225 }
226 
227 #endif /* __NFC_DIGITAL_H */
228