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