xref: /openbmc/linux/include/net/nfc/digital.h (revision afb46f79)
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 
40 	NFC_DIGITAL_RF_TECH_LAST,
41 };
42 
43 /**
44  * Framing configuration passed as param argument to in_configure_hw and
45  * tg_configure_hw for NFC_DIGITAL_CONFIG_FRAMING configuration type.
46  */
47 enum {
48 	NFC_DIGITAL_FRAMING_NFCA_SHORT = 0,
49 	NFC_DIGITAL_FRAMING_NFCA_STANDARD,
50 	NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A,
51 
52 	NFC_DIGITAL_FRAMING_NFCA_T1T,
53 	NFC_DIGITAL_FRAMING_NFCA_T2T,
54 	NFC_DIGITAL_FRAMING_NFCA_T4T,
55 	NFC_DIGITAL_FRAMING_NFCA_NFC_DEP,
56 
57 	NFC_DIGITAL_FRAMING_NFCF,
58 	NFC_DIGITAL_FRAMING_NFCF_T3T,
59 	NFC_DIGITAL_FRAMING_NFCF_NFC_DEP,
60 	NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED,
61 
62 	NFC_DIGITAL_FRAMING_ISO15693_INVENTORY,
63 	NFC_DIGITAL_FRAMING_ISO15693_T5T,
64 
65 	NFC_DIGITAL_FRAMING_LAST,
66 };
67 
68 #define DIGITAL_MDAA_NFCID1_SIZE 3
69 
70 struct digital_tg_mdaa_params {
71 	u16 sens_res;
72 	u8 nfcid1[DIGITAL_MDAA_NFCID1_SIZE];
73 	u8 sel_res;
74 
75 	u8 nfcid2[NFC_NFCID2_MAXSIZE];
76 	u16 sc;
77 };
78 
79 struct nfc_digital_dev;
80 
81 /**
82  * nfc_digital_cmd_complete_t - Definition of command result callback
83  *
84  * @ddev: nfc_digital_device ref
85  * @arg: user data
86  * @resp: response data
87  *
88  * resp pointer can be an error code and will be checked with IS_ERR() macro.
89  * The callback is responsible for freeing resp sk_buff.
90  */
91 typedef void (*nfc_digital_cmd_complete_t)(struct nfc_digital_dev *ddev,
92 					   void *arg, struct sk_buff *resp);
93 
94 /**
95  * Device side NFC Digital operations
96  *
97  * Initiator mode:
98  * @in_configure_hw: Hardware configuration for RF technology and communication
99  *	framing in initiator mode. This is a synchronous function.
100  * @in_send_cmd: Initiator mode data exchange using RF technology and framing
101  *	previously set with in_configure_hw. The peer response is returned
102  *	through callback cb. If an io error occurs or the peer didn't reply
103  *	within the specified timeout (ms), the error code is passed back through
104  *	the resp pointer. This is an asynchronous function.
105  *
106  * Target mode: Only NFC-DEP protocol is supported in target mode.
107  * @tg_configure_hw: Hardware configuration for RF technology and communication
108  *	framing in target mode. This is a synchronous function.
109  * @tg_send_cmd: Target mode data exchange using RF technology and framing
110  *	previously set with tg_configure_hw. The peer next command is returned
111  *	through callback cb. If an io error occurs or the peer didn't reply
112  *	within the specified timeout (ms), the error code is passed back through
113  *	the resp pointer. This is an asynchronous function.
114  * @tg_listen: Put the device in listen mode waiting for data from the peer
115  *	device. This is an asynchronous function.
116  * @tg_listen_mdaa: If supported, put the device in automatic listen mode with
117  *	mode detection and automatic anti-collision. In this mode, the device
118  *	automatically detects the RF technology and executes the anti-collision
119  *	detection using the command responses specified in mdaa_params. The
120  *	mdaa_params structure contains SENS_RES, NFCID1, and SEL_RES for 106A RF
121  *	tech. NFCID2 and system code (sc) for 212F and 424F. The driver returns
122  *	the NFC-DEP ATR_REQ command through cb. The digital stack deducts the RF
123  *	tech by analyzing the SoD of the frame containing the ATR_REQ command.
124  *	This is an asynchronous function.
125  *
126  * @switch_rf: Turns device radio on or off. The stack does not call explicitly
127  *	switch_rf to turn the radio on. A call to in|tg_configure_hw must turn
128  *	the device radio on.
129  * @abort_cmd: Discard the last sent command.
130  *
131  * Notes: Asynchronous functions have a timeout parameter. It is the driver
132  *	responsibility to call the digital stack back through the
133  *	nfc_digital_cmd_complete_t callback when no RF respsonse has been
134  *	received within the specified time (in milliseconds). In that case the
135  *	driver must set the resp sk_buff to ERR_PTR(-ETIMEDOUT).
136  *	Since the digital stack serializes commands to be sent, it's mandatory
137  *	for the driver to handle the timeout correctly. Otherwise the stack
138  *	would not be able to send new commands, waiting for the reply of the
139  *	current one.
140  */
141 struct nfc_digital_ops {
142 	int (*in_configure_hw)(struct nfc_digital_dev *ddev, int type,
143 			       int param);
144 	int (*in_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
145 			   u16 timeout, nfc_digital_cmd_complete_t cb,
146 			   void *arg);
147 
148 	int (*tg_configure_hw)(struct nfc_digital_dev *ddev, int type,
149 			       int param);
150 	int (*tg_send_cmd)(struct nfc_digital_dev *ddev, struct sk_buff *skb,
151 			   u16 timeout, nfc_digital_cmd_complete_t cb,
152 			   void *arg);
153 	int (*tg_listen)(struct nfc_digital_dev *ddev, u16 timeout,
154 			 nfc_digital_cmd_complete_t cb, void *arg);
155 	int (*tg_listen_mdaa)(struct nfc_digital_dev *ddev,
156 			      struct digital_tg_mdaa_params *mdaa_params,
157 			      u16 timeout, nfc_digital_cmd_complete_t cb,
158 			      void *arg);
159 
160 	int (*switch_rf)(struct nfc_digital_dev *ddev, bool on);
161 	void (*abort_cmd)(struct nfc_digital_dev *ddev);
162 };
163 
164 #define NFC_DIGITAL_POLL_MODE_COUNT_MAX	6 /* 106A, 212F, and 424F in & tg */
165 
166 typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
167 
168 struct digital_poll_tech {
169 	u8 rf_tech;
170 	digital_poll_t poll_func;
171 };
172 
173 /**
174  * Driver capabilities - bit mask made of the following values
175  *
176  * @NFC_DIGITAL_DRV_CAPS_IN_CRC: The driver handles CRC calculation in initiator
177  *	mode.
178  * @NFC_DIGITAL_DRV_CAPS_TG_CRC: The driver handles CRC calculation in target
179  *	mode.
180  */
181 #define NFC_DIGITAL_DRV_CAPS_IN_CRC	0x0001
182 #define NFC_DIGITAL_DRV_CAPS_TG_CRC	0x0002
183 
184 struct nfc_digital_dev {
185 	struct nfc_dev *nfc_dev;
186 	struct nfc_digital_ops *ops;
187 
188 	u32 protocols;
189 
190 	int tx_headroom;
191 	int tx_tailroom;
192 
193 	u32 driver_capabilities;
194 	void *driver_data;
195 
196 	struct digital_poll_tech poll_techs[NFC_DIGITAL_POLL_MODE_COUNT_MAX];
197 	u8 poll_tech_count;
198 	u8 poll_tech_index;
199 	struct mutex poll_lock;
200 
201 	struct work_struct cmd_work;
202 	struct work_struct cmd_complete_work;
203 	struct list_head cmd_queue;
204 	struct mutex cmd_lock;
205 
206 	struct work_struct poll_work;
207 
208 	u8 curr_protocol;
209 	u8 curr_rf_tech;
210 	u8 curr_nfc_dep_pni;
211 
212 	u16 target_fsc;
213 
214 	int (*skb_check_crc)(struct sk_buff *skb);
215 	void (*skb_add_crc)(struct sk_buff *skb);
216 };
217 
218 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
219 						    __u32 supported_protocols,
220 						    __u32 driver_capabilities,
221 						    int tx_headroom,
222 						    int tx_tailroom);
223 void nfc_digital_free_device(struct nfc_digital_dev *ndev);
224 int nfc_digital_register_device(struct nfc_digital_dev *ndev);
225 void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
226 
227 static inline void nfc_digital_set_parent_dev(struct nfc_digital_dev *ndev,
228 					      struct device *dev)
229 {
230 	nfc_set_parent_dev(ndev->nfc_dev, dev);
231 }
232 
233 static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
234 					   void *data)
235 {
236 	dev->driver_data = data;
237 }
238 
239 static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
240 {
241 	return dev->driver_data;
242 }
243 
244 #endif /* __NFC_DIGITAL_H */
245