nfc.h revision 84d35492b145cebc000f8fd72818eb25b8e65c04
1/* 2 * Copyright (C) 2011, 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ANDROID_NFC_HAL_INTERFACE_H 18#define ANDROID_NFC_HAL_INTERFACE_H 19 20#include <stdint.h> 21#include <strings.h> 22#include <sys/cdefs.h> 23#include <sys/types.h> 24 25#include <hardware/hardware.h> 26 27__BEGIN_DECLS 28 29 30/* NFC device HAL for NCI-based NFC controllers. 31 * 32 * This HAL allows NCI silicon vendors to make use 33 * of the core NCI stack in Android for their own silicon. 34 * 35 * The responibilities of the NCI HAL implementation 36 * are as follows: 37 * 38 * - Implement the transport to the NFC controller 39 * - Implement each of the HAL methods specified below as applicable to their silicon 40 * - Pass up received NCI messages from the controller to the stack 41 * 42 * A simplified timeline of NCI HAL method calls: 43 * 1) Core NCI stack calls open() 44 * 2) Core NCI stack executes CORE_RESET and CORE_INIT through calls to write() 45 * 3) Core NCI stack calls core_initialized() to allow HAL to do post-init configuration 46 * 4) Core NCI stack calls pre_discover() to allow HAL to prepare for RF discovery 47 * 5) Core NCI stack starts discovery through calls to write() 48 * 6) Core NCI stack stops discovery through calls to write() (e.g. screen turns off) 49 * 7) Core NCI stack calls pre_discover() to prepare for RF discovery (e.g. screen turned back on) 50 * 8) Core NCI stack starts discovery through calls to write() 51 * ... 52 * ... 53 * 9) Core NCI stack calls close() 54 */ 55#define NFC_NCI_HARDWARE_MODULE_ID "nfc_nci" 56#define NFC_NCI_CONTROLLER "nci" 57 58/* 59 * nfc_nci_module_t should contain module-specific parameters 60 */ 61typedef struct nfc_nci_module_t { 62 struct hw_module_t common; 63} nfc_nci_module_t; 64 65/* 66 * HAL events that can be passed back to the stack 67 */ 68typedef uint8_t nfc_event_t; 69 70enum { 71 HAL_NFC_OPEN_CPLT_EVT = 0x00, 72 HAL_NFC_CLOSE_CPLT_EVT = 0x01, 73 HAL_NFC_POST_INIT_CPLT_EVT = 0x02, 74 HAL_NFC_PRE_DISCOVER_CPLT_EVT = 0x03, 75 HAL_NFC_REQUEST_CONTROL_EVT = 0x04, 76 HAL_NFC_RELEASE_CONTROL_EVT = 0x05, 77 HAL_NFC_ERROR_EVT = 0x06 78}; 79 80/* 81 * Allowed status return values for each of the HAL methods 82 */ 83typedef uint8_t nfc_status_t; 84 85enum { 86 HAL_NFC_STATUS_OK = 0x00, 87 HAL_NFC_STATUS_FAILED = 0x01, 88 HAL_NFC_STATUS_ERR_TRANSPORT = 0x02, 89 HAL_NFC_STATUS_ERR_CMD_TIMEOUT = 0x03, 90 HAL_NFC_STATUS_REFUSED = 0x04 91}; 92 93/* 94 * The callback passed in from the NFC stack that the HAL 95 * can use to pass events back to the stack. 96 */ 97typedef void (nfc_stack_callback_t) (nfc_event_t event, nfc_status_t event_status); 98 99/* 100 * The callback passed in from the NFC stack that the HAL 101 * can use to pass incomming data to the stack. 102 */ 103typedef void (nfc_stack_data_callback_t) (uint16_t data_len, uint8_t* p_data); 104 105/* nfc_nci_device_t starts with a hw_device_t struct, 106 * followed by device-specific methods and members. 107 * 108 * All methods in the NCI HAL are asynchronous. 109 */ 110typedef struct nfc_nci_device { 111 struct hw_device_t common; 112 /* 113 * (*open)() Opens the NFC controller device and performs initialization. 114 * This may include patch download and other vendor-specific initialization. 115 * 116 * If open completes successfully, the controller should be ready to perform 117 * NCI initialization - ie accept CORE_RESET and subsequent commands through 118 * the write() call. 119 * 120 * If open() returns 0, the NCI stack will wait for a HAL_NFC_OPEN_CPLT_EVT 121 * before continuing. 122 * 123 * If open() returns any other value, the NCI stack will stop. 124 * 125 */ 126 int (*open)(const struct nfc_nci_device *p_dev, nfc_stack_callback_t *p_cback, 127 nfc_stack_data_callback_t *p_data_cback); 128 129 /* 130 * (*write)() Performs an NCI write. 131 * 132 * This method may queue writes and return immediately. The only 133 * requirement is that the writes are executed in order. 134 */ 135 int (*write)(const struct nfc_nci_device *p_dev, uint16_t data_len, const uint8_t *p_data); 136 137 /* 138 * (*core_initialized)() is called after the CORE_INIT_RSP is received from the NFCC. 139 * At this time, the HAL can do any chip-specific configuration. 140 * 141 * If core_initialized() returns 0, the NCI stack will wait for a HAL_NFC_POST_INIT_CPLT_EVT 142 * before continuing. 143 * 144 * If core_initialized() returns any other value, the NCI stack will continue 145 * immediately. 146 */ 147 int (*core_initialized)(const struct nfc_nci_device *p_dev, uint8_t* p_core_init_rsp_params); 148 149 /* 150 * (*pre_discover)() Is called every time before starting RF discovery. 151 * It is a good place to do vendor-specific configuration that must be 152 * performed every time RF discovery is about to be started. 153 * 154 * If pre_discover() returns 0, the NCI stack will wait for a HAL_NFC_PRE_DISCOVER_CPLT_EVT 155 * before continuing. 156 * 157 * If pre_discover() returns any other value, the NCI stack will start 158 * RF discovery immediately. 159 */ 160 int (*pre_discover)(const struct nfc_nci_device *p_dev); 161 162 /* 163 * (*close)() Closed the NFC controller. Should free all resources. 164 */ 165 int (*close)(const struct nfc_nci_device *p_dev); 166 167 /* 168 * (*control_granted)() Grant HAL the exclusive control to send NCI commands. 169 * Called in response to HAL_REQUEST_CONTROL_EVT. 170 * Must only be called when there are no NCI commands pending. 171 * HAL_RELEASE_CONTROL_EVT will notify when HAL no longer needs exclusive control. 172 */ 173 int (*control_granted)(const struct nfc_nci_device *p_dev); 174 175 /* 176 * (*power_cycle)() Restart controller by power cyle; 177 * HAL_OPEN_CPLT_EVT will notify when operation is complete. 178 */ 179 int (*power_cycle)(const struct nfc_nci_device *p_dev); 180} nfc_nci_device_t; 181 182/* 183 * Convenience methods that the NFC stack can use to open 184 * and close an NCI device 185 */ 186static inline int nfc_nci_open(const struct hw_module_t* module, 187 nfc_nci_device_t** dev) { 188 return module->methods->open(module, NFC_NCI_CONTROLLER, 189 (struct hw_device_t**) dev); 190} 191 192static inline int nfc_nci_close(nfc_nci_device_t* dev) { 193 return dev->common.close(&dev->common); 194} 195/* 196 * End NFC NCI HAL 197 */ 198 199/* 200 * This is a limited NFC HAL for NXP PN544-based devices. 201 * This HAL as Android is moving to 202 * an NCI-based NFC stack. 203 * 204 * All NCI-based NFC controllers should use the NFC-NCI 205 * HAL instead. 206 * Begin PN544 specific HAL 207 */ 208#define NFC_HARDWARE_MODULE_ID "nfc" 209 210#define NFC_PN544_CONTROLLER "pn544" 211 212typedef struct nfc_module_t { 213 /** 214 * Common methods of the NFC NXP PN544 module. This *must* be the first member of 215 * nfc_module_t as users of this structure will cast a hw_module_t to 216 * nfc_module_t pointer in contexts where it's known the hw_module_t references an 217 * nfc_module_t. 218 */ 219 struct hw_module_t common; 220} nfc_module_t; 221 222/* 223 * PN544 linktypes. 224 * UART 225 * I2C 226 * USB (uses UART DAL) 227 */ 228typedef enum { 229 PN544_LINK_TYPE_UART, 230 PN544_LINK_TYPE_I2C, 231 PN544_LINK_TYPE_USB, 232 PN544_LINK_TYPE_INVALID, 233} nfc_pn544_linktype; 234 235typedef struct { 236 /** 237 * Common methods of the NFC NXP PN544 device. This *must* be the first member of 238 * nfc_pn544_device_t as users of this structure will cast a hw_device_t to 239 * nfc_pn544_device_t pointer in contexts where it's known the hw_device_t references an 240 * nfc_pn544_device_t. 241 */ 242 struct hw_device_t common; 243 244 /* The number of EEPROM registers to write */ 245 uint32_t num_eeprom_settings; 246 247 /* The actual EEPROM settings 248 * For PN544, each EEPROM setting is a 4-byte entry, 249 * of the format [0x00, addr_msb, addr_lsb, value]. 250 */ 251 uint8_t* eeprom_settings; 252 253 /* The link type to which the PN544 is connected */ 254 nfc_pn544_linktype linktype; 255 256 /* The device node to which the PN544 is connected */ 257 const char* device_node; 258 259 /* On Crespo we had an I2C issue that would cause us to sometimes read 260 * the I2C slave address (0x57) over the bus. libnfc contains 261 * a hack to ignore this byte and try to read the length byte 262 * again. 263 * Set to 0 to disable the workaround, 1 to enable it. 264 */ 265 uint8_t enable_i2c_workaround; 266 /* I2C slave address. Multiple I2C addresses are 267 * possible for PN544 module. Configure address according to 268 * board design. 269 */ 270 uint8_t i2c_device_address; 271} nfc_pn544_device_t; 272 273static inline int nfc_pn544_open(const struct hw_module_t* module, 274 nfc_pn544_device_t** dev) { 275 return module->methods->open(module, NFC_PN544_CONTROLLER, 276 (struct hw_device_t**) dev); 277} 278 279static inline int nfc_pn544_close(nfc_pn544_device_t* dev) { 280 return dev->common.close(&dev->common); 281} 282/* 283 * End PN544 specific HAL 284 */ 285 286__END_DECLS 287 288#endif // ANDROID_NFC_HAL_INTERFACE_H 289