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 */
 25enum {
 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 */
 34enum {
 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 */
 47enum {
 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
 70struct 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
 79struct 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 */
 91typedef 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 */
141struct 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
166typedef int (*digital_poll_t)(struct nfc_digital_dev *ddev, u8 rf_tech);
167
168struct 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
184struct 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
218struct 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);
223void nfc_digital_free_device(struct nfc_digital_dev *ndev);
224int nfc_digital_register_device(struct nfc_digital_dev *ndev);
225void nfc_digital_unregister_device(struct nfc_digital_dev *ndev);
226
227static 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
233static inline void nfc_digital_set_drvdata(struct nfc_digital_dev *dev,
234					   void *data)
235{
236	dev->driver_data = data;
237}
238
239static inline void *nfc_digital_get_drvdata(struct nfc_digital_dev *dev)
240{
241	return dev->driver_data;
242}
243
244#endif /* __NFC_DIGITAL_H */