1 /* ------------------------------------------------------------------------- */ 2 /* */ 3 /* i2c.h - definitions for the i2c-bus interface */ 4 /* */ 5 /* ------------------------------------------------------------------------- */ 6 /* Copyright (C) 1995-2000 Simon G. Vogl 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ 21 /* ------------------------------------------------------------------------- */ 22 23 /* With some changes from Kyösti Mälkki <[email protected]> and 24 Frodo Looijaard <[email protected]> */ 25 26 #ifndef _LINUX_I2C_H 27 #define _LINUX_I2C_H 28 29 #include <linux/types.h> 30 #ifdef __KERNEL__ 31 #include <linux/module.h> 32 #include <linux/i2c-id.h> 33 #include <linux/mod_devicetable.h> 34 #include <linux/device.h> /* for struct device */ 35 #include <linux/sched.h> /* for completion */ 36 #include <linux/mutex.h> 37 38 extern struct bus_type i2c_bus_type; 39 40 /* --- General options ------------------------------------------------ */ 41 42 struct i2c_msg; 43 struct i2c_algorithm; 44 struct i2c_adapter; 45 struct i2c_client; 46 struct i2c_driver; 47 union i2c_smbus_data; 48 struct i2c_board_info; 49 50 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 51 /* 52 * The master routines are the ones normally used to transmit data to devices 53 * on a bus (or read from them). Apart from two basic transfer functions to 54 * transmit one message at a time, a more complex version can be used to 55 * transmit an arbitrary number of messages without interruption. 56 * @count must be be less than 64k since msg.len is u16. 57 */ 58 extern int i2c_master_send(struct i2c_client *client, const char *buf, 59 int count); 60 extern int i2c_master_recv(struct i2c_client *client, char *buf, int count); 61 62 /* Transfer num messages. 63 */ 64 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 65 int num); 66 67 /* This is the very generalized SMBus access routine. You probably do not 68 want to use this, though; one of the functions below may be much easier, 69 and probably just as fast. 70 Note that we use i2c_adapter here, because you do not need a specific 71 smbus adapter to call this function. */ 72 extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 73 unsigned short flags, char read_write, u8 command, 74 int size, union i2c_smbus_data *data); 75 76 /* Now follow the 'nice' access routines. These also document the calling 77 conventions of i2c_smbus_xfer. */ 78 79 extern s32 i2c_smbus_read_byte(struct i2c_client *client); 80 extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value); 81 extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command); 82 extern s32 i2c_smbus_write_byte_data(struct i2c_client *client, 83 u8 command, u8 value); 84 extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command); 85 extern s32 i2c_smbus_write_word_data(struct i2c_client *client, 86 u8 command, u16 value); 87 /* Returns the number of read bytes */ 88 extern s32 i2c_smbus_read_block_data(struct i2c_client *client, 89 u8 command, u8 *values); 90 extern s32 i2c_smbus_write_block_data(struct i2c_client *client, 91 u8 command, u8 length, const u8 *values); 92 /* Returns the number of read bytes */ 93 extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, 94 u8 command, u8 length, u8 *values); 95 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, 96 u8 command, u8 length, 97 const u8 *values); 98 #endif /* I2C */ 99 100 /** 101 * struct i2c_driver - represent an I2C device driver 102 * @class: What kind of i2c device we instantiate (for detect) 103 * @attach_adapter: Callback for bus addition (for legacy drivers) 104 * @detach_adapter: Callback for bus removal (for legacy drivers) 105 * @probe: Callback for device binding 106 * @remove: Callback for device unbinding 107 * @shutdown: Callback for device shutdown 108 * @suspend: Callback for device suspend 109 * @resume: Callback for device resume 110 * @command: Callback for bus-wide signaling (optional) 111 * @driver: Device driver model driver 112 * @id_table: List of I2C devices supported by this driver 113 * @detect: Callback for device detection 114 * @address_list: The I2C addresses to probe (for detect) 115 * @clients: List of detected clients we created (for i2c-core use only) 116 * 117 * The driver.owner field should be set to the module owner of this driver. 118 * The driver.name field should be set to the name of this driver. 119 * 120 * For automatic device detection, both @detect and @address_data must 121 * be defined. @class should also be set, otherwise only devices forced 122 * with module parameters will be created. The detect function must 123 * fill at least the name field of the i2c_board_info structure it is 124 * handed upon successful detection, and possibly also the flags field. 125 * 126 * If @detect is missing, the driver will still work fine for enumerated 127 * devices. Detected devices simply won't be supported. This is expected 128 * for the many I2C/SMBus devices which can't be detected reliably, and 129 * the ones which can always be enumerated in practice. 130 * 131 * The i2c_client structure which is handed to the @detect callback is 132 * not a real i2c_client. It is initialized just enough so that you can 133 * call i2c_smbus_read_byte_data and friends on it. Don't do anything 134 * else with it. In particular, calling dev_dbg and friends on it is 135 * not allowed. 136 */ 137 struct i2c_driver { 138 unsigned int class; 139 140 /* Notifies the driver that a new bus has appeared or is about to be 141 * removed. You should avoid using this if you can, it will probably 142 * be removed in a near future. 143 */ 144 int (*attach_adapter)(struct i2c_adapter *); 145 int (*detach_adapter)(struct i2c_adapter *); 146 147 /* Standard driver model interfaces */ 148 int (*probe)(struct i2c_client *, const struct i2c_device_id *); 149 int (*remove)(struct i2c_client *); 150 151 /* driver model interfaces that don't relate to enumeration */ 152 void (*shutdown)(struct i2c_client *); 153 int (*suspend)(struct i2c_client *, pm_message_t mesg); 154 int (*resume)(struct i2c_client *); 155 156 /* Alert callback, for example for the SMBus alert protocol. 157 * The format and meaning of the data value depends on the protocol. 158 * For the SMBus alert protocol, there is a single bit of data passed 159 * as the alert response's low bit ("event flag"). 160 */ 161 void (*alert)(struct i2c_client *, unsigned int data); 162 163 /* a ioctl like command that can be used to perform specific functions 164 * with the device. 165 */ 166 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); 167 168 struct device_driver driver; 169 const struct i2c_device_id *id_table; 170 171 /* Device detection callback for automatic device creation */ 172 int (*detect)(struct i2c_client *, struct i2c_board_info *); 173 const unsigned short *address_list; 174 struct list_head clients; 175 }; 176 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) 177 178 /** 179 * struct i2c_client - represent an I2C slave device 180 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address; 181 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking 182 * @addr: Address used on the I2C bus connected to the parent adapter. 183 * @name: Indicates the type of the device, usually a chip name that's 184 * generic enough to hide second-sourcing and compatible revisions. 185 * @adapter: manages the bus segment hosting this I2C device 186 * @driver: device's driver, hence pointer to access routines 187 * @dev: Driver model device node for the slave. 188 * @irq: indicates the IRQ generated by this device (if any) 189 * @detected: member of an i2c_driver.clients list or i2c-core's 190 * userspace_devices list 191 * 192 * An i2c_client identifies a single device (i.e. chip) connected to an 193 * i2c bus. The behaviour exposed to Linux is defined by the driver 194 * managing the device. 195 */ 196 struct i2c_client { 197 unsigned short flags; /* div., see below */ 198 unsigned short addr; /* chip address - NOTE: 7bit */ 199 /* addresses are stored in the */ 200 /* _LOWER_ 7 bits */ 201 char name[I2C_NAME_SIZE]; 202 struct i2c_adapter *adapter; /* the adapter we sit on */ 203 struct i2c_driver *driver; /* and our access routines */ 204 struct device dev; /* the device structure */ 205 int irq; /* irq issued by device */ 206 struct list_head detected; 207 }; 208 #define to_i2c_client(d) container_of(d, struct i2c_client, dev) 209 210 extern struct i2c_client *i2c_verify_client(struct device *dev); 211 212 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) 213 { 214 struct device * const dev = container_of(kobj, struct device, kobj); 215 return to_i2c_client(dev); 216 } 217 218 static inline void *i2c_get_clientdata(const struct i2c_client *dev) 219 { 220 return dev_get_drvdata(&dev->dev); 221 } 222 223 static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) 224 { 225 dev_set_drvdata(&dev->dev, data); 226 } 227 228 /** 229 * struct i2c_board_info - template for device creation 230 * @type: chip type, to initialize i2c_client.name 231 * @flags: to initialize i2c_client.flags 232 * @addr: stored in i2c_client.addr 233 * @platform_data: stored in i2c_client.dev.platform_data 234 * @archdata: copied into i2c_client.dev.archdata 235 * @irq: stored in i2c_client.irq 236 * 237 * I2C doesn't actually support hardware probing, although controllers and 238 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's 239 * a device at a given address. Drivers commonly need more information than 240 * that, such as chip type, configuration, associated IRQ, and so on. 241 * 242 * i2c_board_info is used to build tables of information listing I2C devices 243 * that are present. This information is used to grow the driver model tree. 244 * For mainboards this is done statically using i2c_register_board_info(); 245 * bus numbers identify adapters that aren't yet available. For add-on boards, 246 * i2c_new_device() does this dynamically with the adapter already known. 247 */ 248 struct i2c_board_info { 249 char type[I2C_NAME_SIZE]; 250 unsigned short flags; 251 unsigned short addr; 252 void *platform_data; 253 struct dev_archdata *archdata; 254 int irq; 255 }; 256 257 /** 258 * I2C_BOARD_INFO - macro used to list an i2c device and its address 259 * @dev_type: identifies the device type 260 * @dev_addr: the device's address on the bus. 261 * 262 * This macro initializes essential fields of a struct i2c_board_info, 263 * declaring what has been provided on a particular board. Optional 264 * fields (such as associated irq, or device-specific platform_data) 265 * are provided using conventional syntax. 266 */ 267 #define I2C_BOARD_INFO(dev_type, dev_addr) \ 268 .type = dev_type, .addr = (dev_addr) 269 270 271 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 272 /* Add-on boards should register/unregister their devices; e.g. a board 273 * with integrated I2C, a config eeprom, sensors, and a codec that's 274 * used in conjunction with the primary hardware. 275 */ 276 extern struct i2c_client * 277 i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info); 278 279 /* If you don't know the exact address of an I2C device, use this variant 280 * instead, which can probe for device presence in a list of possible 281 * addresses. 282 */ 283 extern struct i2c_client * 284 i2c_new_probed_device(struct i2c_adapter *adap, 285 struct i2c_board_info *info, 286 unsigned short const *addr_list); 287 288 /* For devices that use several addresses, use i2c_new_dummy() to make 289 * client handles for the extra addresses. 290 */ 291 extern struct i2c_client * 292 i2c_new_dummy(struct i2c_adapter *adap, u16 address); 293 294 extern void i2c_unregister_device(struct i2c_client *); 295 #endif /* I2C */ 296 297 /* Mainboard arch_initcall() code should register all its I2C devices. 298 * This is done at arch_initcall time, before declaring any i2c adapters. 299 * Modules for add-on boards must use other calls. 300 */ 301 #ifdef CONFIG_I2C_BOARDINFO 302 extern int 303 i2c_register_board_info(int busnum, struct i2c_board_info const *info, 304 unsigned n); 305 #else 306 static inline int 307 i2c_register_board_info(int busnum, struct i2c_board_info const *info, 308 unsigned n) 309 { 310 return 0; 311 } 312 #endif /* I2C_BOARDINFO */ 313 314 /* 315 * The following structs are for those who like to implement new bus drivers: 316 * i2c_algorithm is the interface to a class of hardware solutions which can 317 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 318 * to name two of the most common. 319 */ 320 struct i2c_algorithm { 321 /* If an adapter algorithm can't do I2C-level access, set master_xfer 322 to NULL. If an adapter algorithm can do SMBus access, set 323 smbus_xfer. If set to NULL, the SMBus protocol is simulated 324 using common I2C messages */ 325 /* master_xfer should return the number of messages successfully 326 processed, or a negative value on error */ 327 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, 328 int num); 329 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, 330 unsigned short flags, char read_write, 331 u8 command, int size, union i2c_smbus_data *data); 332 333 /* To determine what the adapter supports */ 334 u32 (*functionality) (struct i2c_adapter *); 335 }; 336 337 /* 338 * i2c_adapter is the structure used to identify a physical i2c bus along 339 * with the access algorithms necessary to access it. 340 */ 341 struct i2c_adapter { 342 struct module *owner; 343 unsigned int id; 344 unsigned int class; /* classes to allow probing for */ 345 const struct i2c_algorithm *algo; /* the algorithm to access the bus */ 346 void *algo_data; 347 348 /* data fields that are valid for all devices */ 349 struct rt_mutex bus_lock; 350 351 int timeout; /* in jiffies */ 352 int retries; 353 struct device dev; /* the adapter device */ 354 355 int nr; 356 char name[48]; 357 struct completion dev_released; 358 }; 359 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) 360 361 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) 362 { 363 return dev_get_drvdata(&dev->dev); 364 } 365 366 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) 367 { 368 dev_set_drvdata(&dev->dev, data); 369 } 370 371 /** 372 * i2c_lock_adapter - Prevent access to an I2C bus segment 373 * @adapter: Target I2C bus segment 374 */ 375 static inline void i2c_lock_adapter(struct i2c_adapter *adapter) 376 { 377 rt_mutex_lock(&adapter->bus_lock); 378 } 379 380 /** 381 * i2c_unlock_adapter - Reauthorize access to an I2C bus segment 382 * @adapter: Target I2C bus segment 383 */ 384 static inline void i2c_unlock_adapter(struct i2c_adapter *adapter) 385 { 386 rt_mutex_unlock(&adapter->bus_lock); 387 } 388 389 /*flags for the client struct: */ 390 #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ 391 #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ 392 /* Must equal I2C_M_TEN below */ 393 #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ 394 395 /* i2c adapter classes (bitmask) */ 396 #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ 397 #define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */ 398 #define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */ 399 #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ 400 #define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */ 401 402 /* Internal numbers to terminate lists */ 403 #define I2C_CLIENT_END 0xfffeU 404 405 /* The numbers to use to set I2C bus address */ 406 #define ANY_I2C_BUS 0xffff 407 408 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ 409 #define I2C_ADDRS(addr, addrs...) \ 410 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) 411 412 413 /* ----- functions exported by i2c.o */ 414 415 /* administration... 416 */ 417 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 418 extern int i2c_add_adapter(struct i2c_adapter *); 419 extern int i2c_del_adapter(struct i2c_adapter *); 420 extern int i2c_add_numbered_adapter(struct i2c_adapter *); 421 422 extern int i2c_register_driver(struct module *, struct i2c_driver *); 423 extern void i2c_del_driver(struct i2c_driver *); 424 425 static inline int i2c_add_driver(struct i2c_driver *driver) 426 { 427 return i2c_register_driver(THIS_MODULE, driver); 428 } 429 430 extern struct i2c_client *i2c_use_client(struct i2c_client *client); 431 extern void i2c_release_client(struct i2c_client *client); 432 433 /* call the i2c_client->command() of all attached clients with 434 * the given arguments */ 435 extern void i2c_clients_command(struct i2c_adapter *adap, 436 unsigned int cmd, void *arg); 437 438 extern struct i2c_adapter *i2c_get_adapter(int id); 439 extern void i2c_put_adapter(struct i2c_adapter *adap); 440 441 442 /* Return the functionality mask */ 443 static inline u32 i2c_get_functionality(struct i2c_adapter *adap) 444 { 445 return adap->algo->functionality(adap); 446 } 447 448 /* Return 1 if adapter supports everything we need, 0 if not. */ 449 static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) 450 { 451 return (func & i2c_get_functionality(adap)) == func; 452 } 453 454 /* Return the adapter number for a specific adapter */ 455 static inline int i2c_adapter_id(struct i2c_adapter *adap) 456 { 457 return adap->nr; 458 } 459 #endif /* I2C */ 460 #endif /* __KERNEL__ */ 461 462 /** 463 * struct i2c_msg - an I2C transaction segment beginning with START 464 * @addr: Slave address, either seven or ten bits. When this is a ten 465 * bit address, I2C_M_TEN must be set in @flags and the adapter 466 * must support I2C_FUNC_10BIT_ADDR. 467 * @flags: I2C_M_RD is handled by all adapters. No other flags may be 468 * provided unless the adapter exported the relevant I2C_FUNC_* 469 * flags through i2c_check_functionality(). 470 * @len: Number of data bytes in @buf being read from or written to the 471 * I2C slave address. For read transactions where I2C_M_RECV_LEN 472 * is set, the caller guarantees that this buffer can hold up to 473 * 32 bytes in addition to the initial length byte sent by the 474 * slave (plus, if used, the SMBus PEC); and this value will be 475 * incremented by the number of block data bytes received. 476 * @buf: The buffer into which data is read, or from which it's written. 477 * 478 * An i2c_msg is the low level representation of one segment of an I2C 479 * transaction. It is visible to drivers in the @i2c_transfer() procedure, 480 * to userspace from i2c-dev, and to I2C adapter drivers through the 481 * @i2c_adapter.@master_xfer() method. 482 * 483 * Except when I2C "protocol mangling" is used, all I2C adapters implement 484 * the standard rules for I2C transactions. Each transaction begins with a 485 * START. That is followed by the slave address, and a bit encoding read 486 * versus write. Then follow all the data bytes, possibly including a byte 487 * with SMBus PEC. The transfer terminates with a NAK, or when all those 488 * bytes have been transferred and ACKed. If this is the last message in a 489 * group, it is followed by a STOP. Otherwise it is followed by the next 490 * @i2c_msg transaction segment, beginning with a (repeated) START. 491 * 492 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then 493 * passing certain @flags may have changed those standard protocol behaviors. 494 * Those flags are only for use with broken/nonconforming slaves, and with 495 * adapters which are known to support the specific mangling options they 496 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR). 497 */ 498 struct i2c_msg { 499 __u16 addr; /* slave address */ 500 __u16 flags; 501 #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ 502 #define I2C_M_RD 0x0001 /* read data, from slave to master */ 503 #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 504 #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 505 #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 506 #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ 507 #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ 508 __u16 len; /* msg length */ 509 __u8 *buf; /* pointer to msg data */ 510 }; 511 512 /* To determine what functionality is present */ 513 514 #define I2C_FUNC_I2C 0x00000001 515 #define I2C_FUNC_10BIT_ADDR 0x00000002 516 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */ 517 #define I2C_FUNC_SMBUS_PEC 0x00000008 518 #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */ 519 #define I2C_FUNC_SMBUS_QUICK 0x00010000 520 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000 521 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000 522 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000 523 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000 524 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000 525 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000 526 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000 527 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000 528 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 529 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ 530 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ 531 532 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ 533 I2C_FUNC_SMBUS_WRITE_BYTE) 534 #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \ 535 I2C_FUNC_SMBUS_WRITE_BYTE_DATA) 536 #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \ 537 I2C_FUNC_SMBUS_WRITE_WORD_DATA) 538 #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \ 539 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) 540 #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \ 541 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK) 542 543 #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \ 544 I2C_FUNC_SMBUS_BYTE | \ 545 I2C_FUNC_SMBUS_BYTE_DATA | \ 546 I2C_FUNC_SMBUS_WORD_DATA | \ 547 I2C_FUNC_SMBUS_PROC_CALL | \ 548 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \ 549 I2C_FUNC_SMBUS_I2C_BLOCK | \ 550 I2C_FUNC_SMBUS_PEC) 551 552 /* 553 * Data for SMBus Messages 554 */ 555 #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */ 556 union i2c_smbus_data { 557 __u8 byte; 558 __u16 word; 559 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */ 560 /* and one more for user-space compatibility */ 561 }; 562 563 /* i2c_smbus_xfer read or write markers */ 564 #define I2C_SMBUS_READ 1 565 #define I2C_SMBUS_WRITE 0 566 567 /* SMBus transaction types (size parameter in the above functions) 568 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */ 569 #define I2C_SMBUS_QUICK 0 570 #define I2C_SMBUS_BYTE 1 571 #define I2C_SMBUS_BYTE_DATA 2 572 #define I2C_SMBUS_WORD_DATA 3 573 #define I2C_SMBUS_PROC_CALL 4 574 #define I2C_SMBUS_BLOCK_DATA 5 575 #define I2C_SMBUS_I2C_BLOCK_BROKEN 6 576 #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */ 577 #define I2C_SMBUS_I2C_BLOCK_DATA 8 578 579 #endif /* _LINUX_I2C_H */ 580