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/mod_devicetable.h>
  33 #include <linux/device.h>       /* for struct device */
  34 #include <linux/sched.h>        /* for completion */
  35 #include <linux/mutex.h>
  36 #include <linux/of.h>           /* for struct device_node */
  37 #include <linux/swab.h>         /* for swab16 */
  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(const struct i2c_client *client, const char *buf,
  61                            int count);
  62 extern int i2c_master_recv(const struct i2c_client *client, char *buf,
  63                            int count);
  64
  65 /* Transfer num messages.
  66  */
  67 extern 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. */
  75 extern 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
  82 extern s32 i2c_smbus_read_byte(const struct i2c_client *client);
  83 extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
  84 extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client,
  85                                     u8 command);
  86 extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client,
  87                                      u8 command, u8 value);
  88 extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
  89                                     u8 command);
  90 extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
  91                                      u8 command, u16 value);
  92
  93 static inline s32
  94 i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command)
  95 {
  96         s32 value = i2c_smbus_read_word_data(client, command);
  97
  98         return (value < 0) ? value : swab16(value);
  99 }
 100
 101 static inline s32
 102 i2c_smbus_write_word_swapped(const struct i2c_client *client,
 103                              u8 command, u16 value)
 104 {
 105         return i2c_smbus_write_word_data(client, command, swab16(value));
 106 }
 107
 108 /* Returns the number of read bytes */
 109 extern s32 i2c_smbus_read_block_data(const struct i2c_client *client,
 110                                      u8 command, u8 *values);
 111 extern s32 i2c_smbus_write_block_data(const struct i2c_client *client,
 112                                       u8 command, u8 length, const u8 *values);
 113 /* Returns the number of read bytes */
 114 extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client,
 115                                          u8 command, u8 length, u8 *values);
 116 extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client,
 117                                           u8 command, u8 length,
 118                                           const u8 *values);
 119 #endif /* I2C */
 120
 121 /**
 122  * struct i2c_driver - represent an I2C device driver
 123  * @class: What kind of i2c device we instantiate (for detect)
 124  * @attach_adapter: Callback for bus addition (deprecated)
 125  * @detach_adapter: Callback for bus removal (deprecated)
 126  * @probe: Callback for device binding
 127  * @remove: Callback for device unbinding
 128  * @shutdown: Callback for device shutdown
 129  * @suspend: Callback for device suspend
 130  * @resume: Callback for device resume
 131  * @alert: Alert callback, for example for the SMBus alert protocol
 132  * @command: Callback for bus-wide signaling (optional)
 133  * @driver: Device driver model driver
 134  * @id_table: List of I2C devices supported by this driver
 135  * @detect: Callback for device detection
 136  * @address_list: The I2C addresses to probe (for detect)
 137  * @clients: List of detected clients we created (for i2c-core use only)
 138  *
 139  * The driver.owner field should be set to the module owner of this driver.
 140  * The driver.name field should be set to the name of this driver.
 141  *
 142  * For automatic device detection, both @detect and @address_data must
 143  * be defined. @class should also be set, otherwise only devices forced
 144  * with module parameters will be created. The detect function must
 145  * fill at least the name field of the i2c_board_info structure it is
 146  * handed upon successful detection, and possibly also the flags field.
 147  *
 148  * If @detect is missing, the driver will still work fine for enumerated
 149  * devices. Detected devices simply won't be supported. This is expected
 150  * for the many I2C/SMBus devices which can't be detected reliably, and
 151  * the ones which can always be enumerated in practice.
 152  *
 153  * The i2c_client structure which is handed to the @detect callback is
 154  * not a real i2c_client. It is initialized just enough so that you can
 155  * call i2c_smbus_read_byte_data and friends on it. Don't do anything
 156  * else with it. In particular, calling dev_dbg and friends on it is
 157  * not allowed.
 158  */
 159 struct i2c_driver {
 160         unsigned int class;
 161
 162         /* Notifies the driver that a new bus has appeared or is about to be
 163          * removed. You should avoid using this, it will be removed in a
 164          * near future.
 165          */
 166         int (*attach_adapter)(struct i2c_adapter *) __deprecated;
 167         int (*detach_adapter)(struct i2c_adapter *) __deprecated;
 168
 169         /* Standard driver model interfaces */
 170         int (*probe)(struct i2c_client *, const struct i2c_device_id *);
 171         int (*remove)(struct i2c_client *);
 172
 173         /* driver model interfaces that don't relate to enumeration  */
 174         void (*shutdown)(struct i2c_client *);
 175         int (*suspend)(struct i2c_client *, pm_message_t mesg);
 176         int (*resume)(struct i2c_client *);
 177
 178         /* Alert callback, for example for the SMBus alert protocol.
 179          * The format and meaning of the data value depends on the protocol.
 180          * For the SMBus alert protocol, there is a single bit of data passed
 181          * as the alert response's low bit ("event flag").
 182          */
 183         void (*alert)(struct i2c_client *, unsigned int data);
 184
 185         /* a ioctl like command that can be used to perform specific functions
 186          * with the device.
 187          */
 188         int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
 189
 190         struct device_driver driver;
 191         const struct i2c_device_id *id_table;
 192
 193         /* Device detection callback for automatic device creation */
 194         int (*detect)(struct i2c_client *, struct i2c_board_info *);
 195         const unsigned short *address_list;
 196         struct list_head clients;
 197 };
 198 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
 199
 200 /**
 201  * struct i2c_client - represent an I2C slave device
 202  * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
 203  *      I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
 204  * @addr: Address used on the I2C bus connected to the parent adapter.
 205  * @name: Indicates the type of the device, usually a chip name that's
 206  *      generic enough to hide second-sourcing and compatible revisions.
 207  * @adapter: manages the bus segment hosting this I2C device
 208  * @driver: device's driver, hence pointer to access routines
 209  * @dev: Driver model device node for the slave.
 210  * @irq: indicates the IRQ generated by this device (if any)
 211  * @detected: member of an i2c_driver.clients list or i2c-core's
 212  *      userspace_devices list
 213  *
 214  * An i2c_client identifies a single device (i.e. chip) connected to an
 215  * i2c bus. The behaviour exposed to Linux is defined by the driver
 216  * managing the device.
 217  */
 218 struct i2c_client {
 219         unsigned short flags;           /* div., see below              */
 220         unsigned short addr;            /* chip address - NOTE: 7bit    */
 221                                         /* addresses are stored in the  */
 222                                         /* _LOWER_ 7 bits               */
 223         char name[I2C_NAME_SIZE];
 224         struct i2c_adapter *adapter;    /* the adapter we sit on        */
 225         struct i2c_driver *driver;      /* and our access routines      */
 226         struct device dev;              /* the device structure         */
 227         int irq;                        /* irq issued by device         */
 228         struct list_head detected;
 229 };
 230 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
 231
 232 extern struct i2c_client *i2c_verify_client(struct device *dev);
 233
 234 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
 235 {
 236         struct device * const dev = container_of(kobj, struct device, kobj);
 237         return to_i2c_client(dev);
 238 }
 239
 240 static inline void *i2c_get_clientdata(const struct i2c_client *dev)
 241 {
 242         return dev_get_drvdata(&dev->dev);
 243 }
 244
 245 static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
 246 {
 247         dev_set_drvdata(&dev->dev, data);
 248 }
 249
 250 /**
 251  * struct i2c_board_info - template for device creation
 252  * @type: chip type, to initialize i2c_client.name
 253  * @flags: to initialize i2c_client.flags
 254  * @addr: stored in i2c_client.addr
 255  * @platform_data: stored in i2c_client.dev.platform_data
 256  * @archdata: copied into i2c_client.dev.archdata
 257  * @of_node: pointer to OpenFirmware device node
 258  * @irq: stored in i2c_client.irq
 259  *
 260  * I2C doesn't actually support hardware probing, although controllers and
 261  * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
 262  * a device at a given address.  Drivers commonly need more information than
 263  * that, such as chip type, configuration, associated IRQ, and so on.
 264  *
 265  * i2c_board_info is used to build tables of information listing I2C devices
 266  * that are present.  This information is used to grow the driver model tree.
 267  * For mainboards this is done statically using i2c_register_board_info();
 268  * bus numbers identify adapters that aren't yet available.  For add-on boards,
 269  * i2c_new_device() does this dynamically with the adapter already known.
 270  */
 271 struct i2c_board_info {
 272         char            type[I2C_NAME_SIZE];
 273         unsigned short  flags;
 274         unsigned short  addr;
 275         void            *platform_data;
 276         struct dev_archdata     *archdata;
 277         struct device_node *of_node;
 278         int             irq;
 279 };
 280
 281 /**
 282  * I2C_BOARD_INFO - macro used to list an i2c device and its address
 283  * @dev_type: identifies the device type
 284  * @dev_addr: the device's address on the bus.
 285  *
 286  * This macro initializes essential fields of a struct i2c_board_info,
 287  * declaring what has been provided on a particular board.  Optional
 288  * fields (such as associated irq, or device-specific platform_data)
 289  * are provided using conventional syntax.
 290  */
 291 #define I2C_BOARD_INFO(dev_type, dev_addr) \
 292         .type = dev_type, .addr = (dev_addr)
 293
 294
 295 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 296 /* Add-on boards should register/unregister their devices; e.g. a board
 297  * with integrated I2C, a config eeprom, sensors, and a codec that's
 298  * used in conjunction with the primary hardware.
 299  */
 300 extern struct i2c_client *
 301 i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
 302
 303 /* If you don't know the exact address of an I2C device, use this variant
 304  * instead, which can probe for device presence in a list of possible
 305  * addresses. The "probe" callback function is optional. If it is provided,
 306  * it must return 1 on successful probe, 0 otherwise. If it is not provided,
 307  * a default probing method is used.
 308  */
 309 extern struct i2c_client *
 310 i2c_new_probed_device(struct i2c_adapter *adap,
 311                       struct i2c_board_info *info,
 312                       unsigned short const *addr_list,
 313                       int (*probe)(struct i2c_adapter *, unsigned short addr));
 314
 315 /* Common custom probe functions */
 316 extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
 317
 318 /* For devices that use several addresses, use i2c_new_dummy() to make
 319  * client handles for the extra addresses.
 320  */
 321 extern struct i2c_client *
 322 i2c_new_dummy(struct i2c_adapter *adap, u16 address);
 323
 324 extern void i2c_unregister_device(struct i2c_client *);
 325 #endif /* I2C */
 326
 327 /* Mainboard arch_initcall() code should register all its I2C devices.
 328  * This is done at arch_initcall time, before declaring any i2c adapters.
 329  * Modules for add-on boards must use other calls.
 330  */
 331 #ifdef CONFIG_I2C_BOARDINFO
 332 extern int
 333 i2c_register_board_info(int busnum, struct i2c_board_info const *info,
 334                         unsigned n);
 335 #else
 336 static inline int
 337 i2c_register_board_info(int busnum, struct i2c_board_info const *info,
 338                         unsigned n)
 339 {
 340         return 0;
 341 }
 342 #endif /* I2C_BOARDINFO */
 343
 344 /*
 345  * The following structs are for those who like to implement new bus drivers:
 346  * i2c_algorithm is the interface to a class of hardware solutions which can
 347  * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
 348  * to name two of the most common.
 349  */
 350 struct i2c_algorithm {
 351         /* If an adapter algorithm can't do I2C-level access, set master_xfer
 352            to NULL. If an adapter algorithm can do SMBus access, set
 353            smbus_xfer. If set to NULL, the SMBus protocol is simulated
 354            using common I2C messages */
 355         /* master_xfer should return the number of messages successfully
 356            processed, or a negative value on error */
 357         int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
 358                            int num);
 359         int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
 360                            unsigned short flags, char read_write,
 361                            u8 command, int size, union i2c_smbus_data *data);
 362
 363         /* To determine what the adapter supports */
 364         u32 (*functionality) (struct i2c_adapter *);
 365 };
 366
 367 /*
 368  * i2c_adapter is the structure used to identify a physical i2c bus along
 369  * with the access algorithms necessary to access it.
 370  */
 371 struct i2c_adapter {
 372         struct module *owner;
 373         unsigned int class;               /* classes to allow probing for */
 374         const struct i2c_algorithm *algo; /* the algorithm to access the bus */
 375         void *algo_data;
 376
 377         /* data fields that are valid for all devices   */
 378         struct rt_mutex bus_lock;
 379
 380         int timeout;                    /* in jiffies */
 381         int retries;
 382         struct device dev;              /* the adapter device */
 383
 384         int nr;
 385         char name[48];
 386         struct completion dev_released;
 387
 388         struct mutex userspace_clients_lock;
 389         struct list_head userspace_clients;
 390 };
 391 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
 392
 393 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
 394 {
 395         return dev_get_drvdata(&dev->dev);
 396 }
 397
 398 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
 399 {
 400         dev_set_drvdata(&dev->dev, data);
 401 }
 402
 403 static inline struct i2c_adapter *
 404 i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
 405 {
 406         struct device *parent = adapter->dev.parent;
 407
 408         if (parent != NULL && parent->type == &i2c_adapter_type)
 409                 return to_i2c_adapter(parent);
 410         else
 411                 return NULL;
 412 }
 413
 414 int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
 415
 416 /* Adapter locking functions, exported for shared pin cases */
 417 void i2c_lock_adapter(struct i2c_adapter *);
 418 void i2c_unlock_adapter(struct i2c_adapter *);
 419
 420 /*flags for the client struct: */
 421 #define I2C_CLIENT_PEC  0x04            /* Use Packet Error Checking */
 422 #define I2C_CLIENT_TEN  0x10            /* we have a ten bit chip address */
 423                                         /* Must equal I2C_M_TEN below */
 424 #define I2C_CLIENT_WAKE 0x80            /* for board_info; true iff can wake */
 425
 426 /* i2c adapter classes (bitmask) */
 427 #define I2C_CLASS_HWMON         (1<<0)  /* lm_sensors, ... */
 428 #define I2C_CLASS_DDC           (1<<3)  /* DDC bus on graphics adapters */
 429 #define I2C_CLASS_SPD           (1<<7)  /* Memory modules */
 430
 431 /* Internal numbers to terminate lists */
 432 #define I2C_CLIENT_END          0xfffeU
 433
 434 /* The numbers to use to set I2C bus address */
 435 #define ANY_I2C_BUS             0xffff
 436
 437 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
 438 #define I2C_ADDRS(addr, addrs...) \
 439         ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
 440
 441
 442 /* ----- functions exported by i2c.o */
 443
 444 /* administration...
 445  */
 446 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 447 extern int i2c_add_adapter(struct i2c_adapter *);
 448 extern int i2c_del_adapter(struct i2c_adapter *);
 449 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
 450
 451 extern int i2c_register_driver(struct module *, struct i2c_driver *);
 452 extern void i2c_del_driver(struct i2c_driver *);
 453
 454 static inline int i2c_add_driver(struct i2c_driver *driver)
 455 {
 456         return i2c_register_driver(THIS_MODULE, driver);
 457 }
 458
 459 extern struct i2c_client *i2c_use_client(struct i2c_client *client);
 460 extern void i2c_release_client(struct i2c_client *client);
 461
 462 /* call the i2c_client->command() of all attached clients with
 463  * the given arguments */
 464 extern void i2c_clients_command(struct i2c_adapter *adap,
 465                                 unsigned int cmd, void *arg);
 466
 467 extern struct i2c_adapter *i2c_get_adapter(int nr);
 468 extern void i2c_put_adapter(struct i2c_adapter *adap);
 469
 470
 471 /* Return the functionality mask */
 472 static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
 473 {
 474         return adap->algo->functionality(adap);
 475 }
 476
 477 /* Return 1 if adapter supports everything we need, 0 if not. */
 478 static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
 479 {
 480         return (func & i2c_get_functionality(adap)) == func;
 481 }
 482
 483 /* Return the adapter number for a specific adapter */
 484 static inline int i2c_adapter_id(struct i2c_adapter *adap)
 485 {
 486         return adap->nr;
 487 }
 488 #endif /* I2C */
 489 #endif /* __KERNEL__ */
 490
 491 /**
 492  * struct i2c_msg - an I2C transaction segment beginning with START
 493  * @addr: Slave address, either seven or ten bits.  When this is a ten
 494  *      bit address, I2C_M_TEN must be set in @flags and the adapter
 495  *      must support I2C_FUNC_10BIT_ADDR.
 496  * @flags: I2C_M_RD is handled by all adapters.  No other flags may be
 497  *      provided unless the adapter exported the relevant I2C_FUNC_*
 498  *      flags through i2c_check_functionality().
 499  * @len: Number of data bytes in @buf being read from or written to the
 500  *      I2C slave address.  For read transactions where I2C_M_RECV_LEN
 501  *      is set, the caller guarantees that this buffer can hold up to
 502  *      32 bytes in addition to the initial length byte sent by the
 503  *      slave (plus, if used, the SMBus PEC); and this value will be
 504  *      incremented by the number of block data bytes received.
 505  * @buf: The buffer into which data is read, or from which it's written.
 506  *
 507  * An i2c_msg is the low level representation of one segment of an I2C
 508  * transaction.  It is visible to drivers in the @i2c_transfer() procedure,
 509  * to userspace from i2c-dev, and to I2C adapter drivers through the
 510  * @i2c_adapter.@master_xfer() method.
 511  *
 512  * Except when I2C "protocol mangling" is used, all I2C adapters implement
 513  * the standard rules for I2C transactions.  Each transaction begins with a
 514  * START.  That is followed by the slave address, and a bit encoding read
 515  * versus write.  Then follow all the data bytes, possibly including a byte
 516  * with SMBus PEC.  The transfer terminates with a NAK, or when all those
 517  * bytes have been transferred and ACKed.  If this is the last message in a
 518  * group, it is followed by a STOP.  Otherwise it is followed by the next
 519  * @i2c_msg transaction segment, beginning with a (repeated) START.
 520  *
 521  * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
 522  * passing certain @flags may have changed those standard protocol behaviors.
 523  * Those flags are only for use with broken/nonconforming slaves, and with
 524  * adapters which are known to support the specific mangling options they
 525  * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
 526  */
 527 struct i2c_msg {
 528         __u16 addr;     /* slave address                        */
 529         __u16 flags;
 530 #define I2C_M_TEN               0x0010  /* this is a ten bit chip address */
 531 #define I2C_M_RD                0x0001  /* read data, from slave to master */
 532 #define I2C_M_NOSTART           0x4000  /* if I2C_FUNC_PROTOCOL_MANGLING */
 533 #define I2C_M_REV_DIR_ADDR      0x2000  /* if I2C_FUNC_PROTOCOL_MANGLING */
 534 #define I2C_M_IGNORE_NAK        0x1000  /* if I2C_FUNC_PROTOCOL_MANGLING */
 535 #define I2C_M_NO_RD_ACK         0x0800  /* if I2C_FUNC_PROTOCOL_MANGLING */
 536 #define I2C_M_RECV_LEN          0x0400  /* length will be first received byte */
 537         __u16 len;              /* msg length                           */
 538         __u8 *buf;              /* pointer to msg data                  */
 539 };
 540
 541 /* To determine what functionality is present */
 542
 543 #define I2C_FUNC_I2C                    0x00000001
 544 #define I2C_FUNC_10BIT_ADDR             0x00000002
 545 #define I2C_FUNC_PROTOCOL_MANGLING      0x00000004 /* I2C_M_NOSTART etc. */
 546 #define I2C_FUNC_SMBUS_PEC              0x00000008
 547 #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL  0x00008000 /* SMBus 2.0 */
 548 #define I2C_FUNC_SMBUS_QUICK            0x00010000
 549 #define I2C_FUNC_SMBUS_READ_BYTE        0x00020000
 550 #define I2C_FUNC_SMBUS_WRITE_BYTE       0x00040000
 551 #define I2C_FUNC_SMBUS_READ_BYTE_DATA   0x00080000
 552 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA  0x00100000
 553 #define I2C_FUNC_SMBUS_READ_WORD_DATA   0x00200000
 554 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA  0x00400000
 555 #define I2C_FUNC_SMBUS_PROC_CALL        0x00800000
 556 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA  0x01000000
 557 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
 558 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK   0x04000000 /* I2C-like block xfer  */
 559 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK  0x08000000 /* w/ 1-byte reg. addr. */
 560
 561 #define I2C_FUNC_SMBUS_BYTE             (I2C_FUNC_SMBUS_READ_BYTE | \
 562                                          I2C_FUNC_SMBUS_WRITE_BYTE)
 563 #define I2C_FUNC_SMBUS_BYTE_DATA        (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
 564                                          I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
 565 #define I2C_FUNC_SMBUS_WORD_DATA        (I2C_FUNC_SMBUS_READ_WORD_DATA | \
 566                                          I2C_FUNC_SMBUS_WRITE_WORD_DATA)
 567 #define I2C_FUNC_SMBUS_BLOCK_DATA       (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
 568                                          I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
 569 #define I2C_FUNC_SMBUS_I2C_BLOCK        (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
 570                                          I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
 571
 572 #define I2C_FUNC_SMBUS_EMUL             (I2C_FUNC_SMBUS_QUICK | \
 573                                          I2C_FUNC_SMBUS_BYTE | \
 574                                          I2C_FUNC_SMBUS_BYTE_DATA | \
 575                                          I2C_FUNC_SMBUS_WORD_DATA | \
 576                                          I2C_FUNC_SMBUS_PROC_CALL | \
 577                                          I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
 578                                          I2C_FUNC_SMBUS_I2C_BLOCK | \
 579                                          I2C_FUNC_SMBUS_PEC)
 580
 581 /*
 582  * Data for SMBus Messages
 583  */
 584 #define I2C_SMBUS_BLOCK_MAX     32      /* As specified in SMBus standard */
 585 union i2c_smbus_data {
 586         __u8 byte;
 587         __u16 word;
 588         __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
 589                                /* and one more for user-space compatibility */
 590 };
 591
 592 /* i2c_smbus_xfer read or write markers */
 593 #define I2C_SMBUS_READ  1
 594 #define I2C_SMBUS_WRITE 0
 595
 596 /* SMBus transaction types (size parameter in the above functions)
 597    Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
 598 #define I2C_SMBUS_QUICK             0
 599 #define I2C_SMBUS_BYTE              1
 600 #define I2C_SMBUS_BYTE_DATA         2
 601 #define I2C_SMBUS_WORD_DATA         3
 602 #define I2C_SMBUS_PROC_CALL         4
 603 #define I2C_SMBUS_BLOCK_DATA        5
 604 #define I2C_SMBUS_I2C_BLOCK_BROKEN  6
 605 #define I2C_SMBUS_BLOCK_PROC_CALL   7           /* SMBus 2.0 */
 606 #define I2C_SMBUS_I2C_BLOCK_DATA    8
 607
 608 #endif /* _LINUX_I2C_H */