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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 <kmalkki@cc.hut.fi> and 24 Frodo Looijaard <frodol@dds.nl> */ 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#include <linux/of.h> /* for struct device_node */ 38 39extern struct bus_type i2c_bus_type; 40extern struct device_type i2c_adapter_type; 41 42/* --- General options ------------------------------------------------ */ 43 44struct i2c_msg; 45struct i2c_algorithm; 46struct i2c_adapter; 47struct i2c_client; 48struct i2c_driver; 49union i2c_smbus_data; 50struct i2c_board_info; 51 52#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 53/* 54 * The master routines are the ones normally used to transmit data to devices 55 * on a bus (or read from them). Apart from two basic transfer functions to 56 * transmit one message at a time, a more complex version can be used to 57 * transmit an arbitrary number of messages without interruption. 58 * @count must be be less than 64k since msg.len is u16. 59 */ 60extern int i2c_master_send(const struct i2c_client *client, const char *buf, 61 int count); 62extern int i2c_master_recv(const struct i2c_client *client, char *buf, 63 int count); 64 65/* Transfer num messages. 66 */ 67extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 68 int num); 69 70/* This is the very generalized SMBus access routine. You probably do not 71 want to use this, though; one of the functions below may be much easier, 72 and probably just as fast. 73 Note that we use i2c_adapter here, because you do not need a specific 74 smbus adapter to call this function. */ 75extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 76 unsigned short flags, char read_write, u8 command, 77 int size, union i2c_smbus_data *data); 78 79/* Now follow the 'nice' access routines. These also document the calling 80 conventions of i2c_smbus_xfer. */ 81 82extern s32 i2c_smbus_read_byte(const struct i2c_client *client); 83extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); 84extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client, 85 u8 command); 86extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client, 87 u8 command, u8 value); 88extern s32 i2c_smbus_read_word_data(const struct i2c_client *client, 89 u8 command); 90extern s32 i2c_smbus_write_word_data(const struct i2c_client *client, 91 u8 command, u16 value); 92/* Returns the number of read bytes */ 93extern s32 i2c_smbus_read_block_data(const struct i2c_client *client, 94 u8 command, u8 *values); 95extern s32 i2c_smbus_write_block_data(const struct i2c_client *client, 96 u8 command, u8 length, const u8 *values); 97/* Returns the number of read bytes */ 98extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, 99 u8 command, u8 length, u8 *values); 100extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, 101 u8 command, u8 length, 102 const u8 *values); 103#endif /* I2C */ 104 105/** 106 * struct i2c_driver - represent an I2C device driver 107 * @class: What kind of i2c device we instantiate (for detect) 108 * @attach_adapter: Callback for bus addition (for legacy drivers) 109 * @detach_adapter: Callback for bus removal (for legacy drivers) 110 * @probe: Callback for device binding 111 * @remove: Callback for device unbinding 112 * @shutdown: Callback for device shutdown 113 * @suspend: Callback for device suspend 114 * @resume: Callback for device resume 115 * @alert: Alert callback, for example for the SMBus alert protocol 116 * @command: Callback for bus-wide signaling (optional) 117 * @driver: Device driver model driver 118 * @id_table: List of I2C devices supported by this driver 119 * @detect: Callback for device detection 120 * @address_list: The I2C addresses to probe (for detect) 121 * @clients: List of detected clients we created (for i2c-core use only) 122 * 123 * The driver.owner field should be set to the module owner of this driver. 124 * The driver.name field should be set to the name of this driver. 125 * 126 * For automatic device detection, both @detect and @address_data must 127 * be defined. @class should also be set, otherwise only devices forced 128 * with module parameters will be created. The detect function must 129 * fill at least the name field of the i2c_board_info structure it is 130 * handed upon successful detection, and possibly also the flags field. 131 * 132 * If @detect is missing, the driver will still work fine for enumerated 133 * devices. Detected devices simply won't be supported. This is expected 134 * for the many I2C/SMBus devices which can't be detected reliably, and 135 * the ones which can always be enumerated in practice. 136 * 137 * The i2c_client structure which is handed to the @detect callback is 138 * not a real i2c_client. It is initialized just enough so that you can 139 * call i2c_smbus_read_byte_data and friends on it. Don't do anything 140 * else with it. In particular, calling dev_dbg and friends on it is 141 * not allowed. 142 */ 143struct i2c_driver { 144 unsigned int class; 145 146 /* Notifies the driver that a new bus has appeared or is about to be 147 * removed. You should avoid using this if you can, it will probably 148 * be removed in a near future. 149 */ 150 int (*attach_adapter)(struct i2c_adapter *); 151 int (*detach_adapter)(struct i2c_adapter *); 152 153 /* Standard driver model interfaces */ 154 int (*probe)(struct i2c_client *, const struct i2c_device_id *); 155 int (*remove)(struct i2c_client *); 156 157 /* driver model interfaces that don't relate to enumeration */ 158 void (*shutdown)(struct i2c_client *); 159 int (*suspend)(struct i2c_client *, pm_message_t mesg); 160 int (*resume)(struct i2c_client *); 161 162 /* Alert callback, for example for the SMBus alert protocol. 163 * The format and meaning of the data value depends on the protocol. 164 * For the SMBus alert protocol, there is a single bit of data passed 165 * as the alert response's low bit ("event flag"). 166 */ 167 void (*alert)(struct i2c_client *, unsigned int data); 168 169 /* a ioctl like command that can be used to perform specific functions 170 * with the device. 171 */ 172 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); 173 174 struct device_driver driver; 175 const struct i2c_device_id *id_table; 176 177 /* Device detection callback for automatic device creation */ 178 int (*detect)(struct i2c_client *, struct i2c_board_info *); 179 const unsigned short *address_list; 180 struct list_head clients; 181}; 182#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) 183 184/** 185 * struct i2c_client - represent an I2C slave device 186 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address; 187 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking 188 * @addr: Address used on the I2C bus connected to the parent adapter. 189 * @name: Indicates the type of the device, usually a chip name that's 190 * generic enough to hide second-sourcing and compatible revisions. 191 * @adapter: manages the bus segment hosting this I2C device 192 * @driver: device's driver, hence pointer to access routines 193 * @dev: Driver model device node for the slave. 194 * @irq: indicates the IRQ generated by this device (if any) 195 * @detected: member of an i2c_driver.clients list or i2c-core's 196 * userspace_devices list 197 * 198 * An i2c_client identifies a single device (i.e. chip) connected to an 199 * i2c bus. The behaviour exposed to Linux is defined by the driver 200 * managing the device. 201 */ 202struct i2c_client { 203 unsigned short flags; /* div., see below */ 204 unsigned short addr; /* chip address - NOTE: 7bit */ 205 /* addresses are stored in the */ 206 /* _LOWER_ 7 bits */ 207 char name[I2C_NAME_SIZE]; 208 struct i2c_adapter *adapter; /* the adapter we sit on */ 209 struct i2c_driver *driver; /* and our access routines */ 210 struct device dev; /* the device structure */ 211 int irq; /* irq issued by device */ 212 struct list_head detected; 213}; 214#define to_i2c_client(d) container_of(d, struct i2c_client, dev) 215 216extern struct i2c_client *i2c_verify_client(struct device *dev); 217 218static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) 219{ 220 struct device * const dev = container_of(kobj, struct device, kobj); 221 return to_i2c_client(dev); 222} 223 224static inline void *i2c_get_clientdata(const struct i2c_client *dev) 225{ 226 return dev_get_drvdata(&dev->dev); 227} 228 229static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) 230{ 231 dev_set_drvdata(&dev->dev, data); 232} 233 234/** 235 * struct i2c_board_info - template for device creation 236 * @type: chip type, to initialize i2c_client.name 237 * @flags: to initialize i2c_client.flags 238 * @addr: stored in i2c_client.addr 239 * @platform_data: stored in i2c_client.dev.platform_data 240 * @archdata: copied into i2c_client.dev.archdata 241 * @of_node: pointer to OpenFirmware device node 242 * @irq: stored in i2c_client.irq 243 * 244 * I2C doesn't actually support hardware probing, although controllers and 245 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's 246 * a device at a given address. Drivers commonly need more information than 247 * that, such as chip type, configuration, associated IRQ, and so on. 248 * 249 * i2c_board_info is used to build tables of information listing I2C devices 250 * that are present. This information is used to grow the driver model tree. 251 * For mainboards this is done statically using i2c_register_board_info(); 252 * bus numbers identify adapters that aren't yet available. For add-on boards, 253 * i2c_new_device() does this dynamically with the adapter already known. 254 */ 255struct i2c_board_info { 256 char type[I2C_NAME_SIZE]; 257 unsigned short flags; 258 unsigned short addr; 259 void *platform_data; 260 struct dev_archdata *archdata; 261#ifdef CONFIG_OF 262 struct device_node *of_node; 263#endif 264 int irq; 265}; 266 267/** 268 * I2C_BOARD_INFO - macro used to list an i2c device and its address 269 * @dev_type: identifies the device type 270 * @dev_addr: the device's address on the bus. 271 * 272 * This macro initializes essential fields of a struct i2c_board_info, 273 * declaring what has been provided on a particular board. Optional 274 * fields (such as associated irq, or device-specific platform_data) 275 * are provided using conventional syntax. 276 */ 277#define I2C_BOARD_INFO(dev_type, dev_addr) \ 278 .type = dev_type, .addr = (dev_addr) 279 280 281#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 282/* Add-on boards should register/unregister their devices; e.g. a board 283 * with integrated I2C, a config eeprom, sensors, and a codec that's 284 * used in conjunction with the primary hardware. 285 */ 286extern struct i2c_client * 287i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info); 288 289/* If you don't know the exact address of an I2C device, use this variant 290 * instead, which can probe for device presence in a list of possible 291 * addresses. The "probe" callback function is optional. If it is provided, 292 * it must return 1 on successful probe, 0 otherwise. If it is not provided, 293 * a default probing method is used. 294 */ 295extern struct i2c_client * 296i2c_new_probed_device(struct i2c_adapter *adap, 297 struct i2c_board_info *info, 298 unsigned short const *addr_list, 299 int (*probe)(struct i2c_adapter *, unsigned short addr)); 300 301/* Common custom probe functions */ 302extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); 303 304/* For devices that use several addresses, use i2c_new_dummy() to make 305 * client handles for the extra addresses. 306 */ 307extern struct i2c_client * 308i2c_new_dummy(struct i2c_adapter *adap, u16 address); 309 310extern void i2c_unregister_device(struct i2c_client *); 311#endif /* I2C */ 312 313/* Mainboard arch_initcall() code should register all its I2C devices. 314 * This is done at arch_initcall time, before declaring any i2c adapters. 315 * Modules for add-on boards must use other calls. 316 */ 317#ifdef CONFIG_I2C_BOARDINFO 318extern int 319i2c_register_board_info(int busnum, struct i2c_board_info const *info, 320 unsigned n); 321#else 322static inline int 323i2c_register_board_info(int busnum, struct i2c_board_info const *info, 324 unsigned n) 325{ 326 return 0; 327} 328#endif /* I2C_BOARDINFO */ 329 330/* 331 * The following structs are for those who like to implement new bus drivers: 332 * i2c_algorithm is the interface to a class of hardware solutions which can 333 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 334 * to name two of the most common. 335 */ 336struct i2c_algorithm { 337 /* If an adapter algorithm can't do I2C-level access, set master_xfer 338 to NULL. If an adapter algorithm can do SMBus access, set 339 smbus_xfer. If set to NULL, the SMBus protocol is simulated 340 using common I2C messages */ 341 /* master_xfer should return the number of messages successfully 342 processed, or a negative value on error */ 343 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, 344 int num); 345 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, 346 unsigned short flags, char read_write, 347 u8 command, int size, union i2c_smbus_data *data); 348 349 /* To determine what the adapter supports */ 350 u32 (*functionality) (struct i2c_adapter *); 351}; 352 353/* 354 * i2c_adapter is the structure used to identify a physical i2c bus along 355 * with the access algorithms necessary to access it. 356 */ 357struct i2c_adapter { 358 struct module *owner; 359 unsigned int id __deprecated; 360 unsigned int class; /* classes to allow probing for */ 361 const struct i2c_algorithm *algo; /* the algorithm to access the bus */ 362 void *algo_data; 363 364 /* data fields that are valid for all devices */ 365 struct rt_mutex bus_lock; 366 367 int timeout; /* in jiffies */ 368 int retries; 369 struct device dev; /* the adapter device */ 370 371 int nr; 372 char name[48]; 373 struct completion dev_released; 374 375 struct mutex userspace_clients_lock; 376 struct list_head userspace_clients; 377}; 378#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) 379 380static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) 381{ 382 return dev_get_drvdata(&dev->dev); 383} 384 385static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) 386{ 387 dev_set_drvdata(&dev->dev, data); 388} 389 390static inline struct i2c_adapter * 391i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) 392{ 393 struct device *parent = adapter->dev.parent; 394 395 if (parent != NULL && parent->type == &i2c_adapter_type) 396 return to_i2c_adapter(parent); 397 else 398 return NULL; 399} 400 401/* Adapter locking functions, exported for shared pin cases */ 402void i2c_lock_adapter(struct i2c_adapter *); 403void i2c_unlock_adapter(struct i2c_adapter *); 404 405/*flags for the client struct: */ 406#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ 407#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ 408 /* Must equal I2C_M_TEN below */ 409#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ 410 411/* i2c adapter classes (bitmask) */ 412#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ 413#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ 414#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */ 415 416/* Internal numbers to terminate lists */ 417#define I2C_CLIENT_END 0xfffeU 418 419/* The numbers to use to set I2C bus address */ 420#define ANY_I2C_BUS 0xffff 421 422/* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ 423#define I2C_ADDRS(addr, addrs...) \ 424 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) 425 426 427/* ----- functions exported by i2c.o */ 428 429/* administration... 430 */ 431#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 432extern int i2c_add_adapter(struct i2c_adapter *); 433extern int i2c_del_adapter(struct i2c_adapter *); 434extern int i2c_add_numbered_adapter(struct i2c_adapter *); 435 436extern int i2c_register_driver(struct module *, struct i2c_driver *); 437extern void i2c_del_driver(struct i2c_driver *); 438 439static inline int i2c_add_driver(struct i2c_driver *driver) 440{ 441 return i2c_register_driver(THIS_MODULE, driver); 442} 443 444extern struct i2c_client *i2c_use_client(struct i2c_client *client); 445extern void i2c_release_client(struct i2c_client *client); 446 447/* call the i2c_client->command() of all attached clients with 448 * the given arguments */ 449extern void i2c_clients_command(struct i2c_adapter *adap, 450 unsigned int cmd, void *arg); 451 452extern struct i2c_adapter *i2c_get_adapter(int id); 453extern void i2c_put_adapter(struct i2c_adapter *adap); 454 455 456/* Return the functionality mask */ 457static inline u32 i2c_get_functionality(struct i2c_adapter *adap) 458{ 459 return adap->algo->functionality(adap); 460} 461 462/* Return 1 if adapter supports everything we need, 0 if not. */ 463static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) 464{ 465 return (func & i2c_get_functionality(adap)) == func; 466} 467 468/* Return the adapter number for a specific adapter */ 469static inline int i2c_adapter_id(struct i2c_adapter *adap) 470{ 471 return adap->nr; 472} 473#endif /* I2C */ 474#endif /* __KERNEL__ */ 475 476/** 477 * struct i2c_msg - an I2C transaction segment beginning with START 478 * @addr: Slave address, either seven or ten bits. When this is a ten 479 * bit address, I2C_M_TEN must be set in @flags and the adapter 480 * must support I2C_FUNC_10BIT_ADDR. 481 * @flags: I2C_M_RD is handled by all adapters. No other flags may be 482 * provided unless the adapter exported the relevant I2C_FUNC_* 483 * flags through i2c_check_functionality(). 484 * @len: Number of data bytes in @buf being read from or written to the 485 * I2C slave address. For read transactions where I2C_M_RECV_LEN 486 * is set, the caller guarantees that this buffer can hold up to 487 * 32 bytes in addition to the initial length byte sent by the 488 * slave (plus, if used, the SMBus PEC); and this value will be 489 * incremented by the number of block data bytes received. 490 * @buf: The buffer into which data is read, or from which it's written. 491 * 492 * An i2c_msg is the low level representation of one segment of an I2C 493 * transaction. It is visible to drivers in the @i2c_transfer() procedure, 494 * to userspace from i2c-dev, and to I2C adapter drivers through the 495 * @i2c_adapter.@master_xfer() method. 496 * 497 * Except when I2C "protocol mangling" is used, all I2C adapters implement 498 * the standard rules for I2C transactions. Each transaction begins with a 499 * START. That is followed by the slave address, and a bit encoding read 500 * versus write. Then follow all the data bytes, possibly including a byte 501 * with SMBus PEC. The transfer terminates with a NAK, or when all those 502 * bytes have been transferred and ACKed. If this is the last message in a 503 * group, it is followed by a STOP. Otherwise it is followed by the next 504 * @i2c_msg transaction segment, beginning with a (repeated) START. 505 * 506 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then 507 * passing certain @flags may have changed those standard protocol behaviors. 508 * Those flags are only for use with broken/nonconforming slaves, and with 509 * adapters which are known to support the specific mangling options they 510 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR). 511 */ 512struct i2c_msg { 513 __u16 addr; /* slave address */ 514 __u16 flags; 515#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ 516#define I2C_M_RD 0x0001 /* read data, from slave to master */ 517#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 518#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 519#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ 520#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ 521#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ 522 __u16 len; /* msg length */ 523 __u8 *buf; /* pointer to msg data */ 524}; 525 526/* To determine what functionality is present */ 527 528#define I2C_FUNC_I2C 0x00000001 529#define I2C_FUNC_10BIT_ADDR 0x00000002 530#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */ 531#define I2C_FUNC_SMBUS_PEC 0x00000008 532#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */ 533#define I2C_FUNC_SMBUS_QUICK 0x00010000 534#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000 535#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000 536#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000 537#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000 538#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000 539#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000 540#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000 541#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000 542#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 543#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ 544#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ 545 546#define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ 547 I2C_FUNC_SMBUS_WRITE_BYTE) 548#define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \ 549 I2C_FUNC_SMBUS_WRITE_BYTE_DATA) 550#define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \ 551 I2C_FUNC_SMBUS_WRITE_WORD_DATA) 552#define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \ 553 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) 554#define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \ 555 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK) 556 557#define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \ 558 I2C_FUNC_SMBUS_BYTE | \ 559 I2C_FUNC_SMBUS_BYTE_DATA | \ 560 I2C_FUNC_SMBUS_WORD_DATA | \ 561 I2C_FUNC_SMBUS_PROC_CALL | \ 562 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \ 563 I2C_FUNC_SMBUS_I2C_BLOCK | \ 564 I2C_FUNC_SMBUS_PEC) 565 566/* 567 * Data for SMBus Messages 568 */ 569#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */ 570union i2c_smbus_data { 571 __u8 byte; 572 __u16 word; 573 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */ 574 /* and one more for user-space compatibility */ 575}; 576 577/* i2c_smbus_xfer read or write markers */ 578#define I2C_SMBUS_READ 1 579#define I2C_SMBUS_WRITE 0 580 581/* SMBus transaction types (size parameter in the above functions) 582 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */ 583#define I2C_SMBUS_QUICK 0 584#define I2C_SMBUS_BYTE 1 585#define I2C_SMBUS_BYTE_DATA 2 586#define I2C_SMBUS_WORD_DATA 3 587#define I2C_SMBUS_PROC_CALL 4 588#define I2C_SMBUS_BLOCK_DATA 5 589#define I2C_SMBUS_I2C_BLOCK_BROKEN 6 590#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */ 591#define I2C_SMBUS_I2C_BLOCK_DATA 8 592 593#endif /* _LINUX_I2C_H */