include/linux/i2c.h

   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
  39 extern struct bus_type i2c_bus_type;
  40 extern struct device_type i2c_adapter_type;
  41
  42 /* --- General options ------------------------------------------------ */
  43
  44 struct i2c_msg;
  45 struct i2c_algorithm;
  46 struct i2c_adapter;
  47 struct i2c_client;
  48 struct i2c_driver;
  49 union i2c_smbus_data;
  50 struct 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  */
  60 extern int i2c_master_send(struct i2c_client *client, const char *buf,
  61                            int count);
  62 extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
  63
  64 /* Transfer num messages.
  65  */
  66 extern 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. */
  74 extern 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
  81 extern s32 i2c_smbus_read_byte(struct i2c_client *client);
  82 extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value);
  83 extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);
  84 extern s32 i2c_smbus_write_byte_data(struct i2c_client *client,
  85                                      u8 command, u8 value);
  86 extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
  87 extern s32 i2c_smbus_write_word_data(struct i2c_client *client,
  88                                      u8 command, u16 value);
  89 /* Returns the number of read bytes */
  90 extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
  91                                      u8 command, u8 *values);
  92 extern 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 */
  95 extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client,
  96                                          u8 command, u8 length, u8 *values);
  97 extern 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  */
 140 struct 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  */
 199 struct 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
 213 extern struct i2c_client *i2c_verify_client(struct device *dev);
 214
 215 static 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
 221 static inline void *i2c_get_clientdata(const struct i2c_client *dev)
 222 {
 223         return dev_get_drvdata(&dev->dev);
 224 }
 225
 226 static 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  */
 252 struct 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  */
 283 extern struct i2c_client *
 284 i2c_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  */
 292 extern struct i2c_client *
 293 i2c_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 */
 299 extern 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  */
 304 extern struct i2c_client *
 305 i2c_new_dummy(struct i2c_adapter *adap, u16 address);
 306
 307 extern 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
 315 extern int
 316 i2c_register_board_info(int busnum, struct i2c_board_info const *info,
 317                         unsigned n);
 318 #else
 319 static inline int
 320 i2c_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  */
 333 struct 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  */
 354 struct i2c_adapter {
 355         struct module *owner;
 356         unsigned int id;
 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
 377 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
 378 {
 379         return dev_get_drvdata(&dev->dev);
 380 }
 381
 382 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
 383 {
 384         dev_set_drvdata(&dev->dev, data);
 385 }
 386
 387 static inline struct i2c_adapter *
 388 i2c_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 */
 399 void i2c_lock_adapter(struct i2c_adapter *);
 400 void 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)
 429 extern int i2c_add_adapter(struct i2c_adapter *);
 430 extern int i2c_del_adapter(struct i2c_adapter *);
 431 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
 432
 433 extern int i2c_register_driver(struct module *, struct i2c_driver *);
 434 extern void i2c_del_driver(struct i2c_driver *);
 435
 436 static inline int i2c_add_driver(struct i2c_driver *driver)
 437 {
 438         return i2c_register_driver(THIS_MODULE, driver);
 439 }
 440
 441 extern struct i2c_client *i2c_use_client(struct i2c_client *client);
 442 extern void i2c_release_client(struct i2c_client *client);
 443
 444 /* call the i2c_client->command() of all attached clients with
 445  * the given arguments */
 446 extern void i2c_clients_command(struct i2c_adapter *adap,
 447                                 unsigned int cmd, void *arg);
 448
 449 extern struct i2c_adapter *i2c_get_adapter(int id);
 450 extern void i2c_put_adapter(struct i2c_adapter *adap);
 451
 452
 453 /* Return the functionality mask */
 454 static 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. */
 460 static 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 */
 466 static 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  */
 509 struct 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 */
 567 union 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 */