1 /* ------------------------------------------------------------------------- */
3 /* i2c.h - definitions for the i2c-bus interface */
5 /* ------------------------------------------------------------------------- */
6 /* Copyright (C) 1995-2000 Simon G. Vogl
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.
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.
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 /* ------------------------------------------------------------------------- */
23 /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
24 Frodo Looijaard <frodol@dds.nl> */
29 #include <linux/types.h>
31 #include <linux/mod_devicetable.h>
32 #include <linux/device.h> /* for struct device */
33 #include <linux/sched.h> /* for completion */
34 #include <linux/mutex.h>
35 #include <linux/of.h> /* for struct device_node */
36 #include <linux/swab.h> /* for swab16 */
38 extern struct bus_type i2c_bus_type
;
39 extern struct device_type i2c_adapter_type
;
41 /* --- General options ------------------------------------------------ */
49 struct i2c_board_info
;
53 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
55 * The master routines are the ones normally used to transmit data to devices
56 * on a bus (or read from them). Apart from two basic transfer functions to
57 * transmit one message at a time, a more complex version can be used to
58 * transmit an arbitrary number of messages without interruption.
59 * @count must be be less than 64k since msg.len is u16.
61 extern int i2c_master_send(const struct i2c_client
*client
, const char *buf
,
63 extern int i2c_master_recv(const struct i2c_client
*client
, char *buf
,
66 /* Transfer num messages.
68 extern int i2c_transfer(struct i2c_adapter
*adap
, struct i2c_msg
*msgs
,
71 /* This is the very generalized SMBus access routine. You probably do not
72 want to use this, though; one of the functions below may be much easier,
73 and probably just as fast.
74 Note that we use i2c_adapter here, because you do not need a specific
75 smbus adapter to call this function. */
76 extern s32
i2c_smbus_xfer(struct i2c_adapter
*adapter
, u16 addr
,
77 unsigned short flags
, char read_write
, u8 command
,
78 int size
, union i2c_smbus_data
*data
);
80 /* Now follow the 'nice' access routines. These also document the calling
81 conventions of i2c_smbus_xfer. */
83 extern s32
i2c_smbus_read_byte(const struct i2c_client
*client
);
84 extern s32
i2c_smbus_write_byte(const struct i2c_client
*client
, u8 value
);
85 extern s32
i2c_smbus_read_byte_data(const struct i2c_client
*client
,
87 extern s32
i2c_smbus_write_byte_data(const struct i2c_client
*client
,
88 u8 command
, u8 value
);
89 extern s32
i2c_smbus_read_word_data(const struct i2c_client
*client
,
91 extern s32
i2c_smbus_write_word_data(const struct i2c_client
*client
,
92 u8 command
, u16 value
);
95 i2c_smbus_read_word_swapped(const struct i2c_client
*client
, u8 command
)
97 s32 value
= i2c_smbus_read_word_data(client
, command
);
99 return (value
< 0) ? value
: swab16(value
);
103 i2c_smbus_write_word_swapped(const struct i2c_client
*client
,
104 u8 command
, u16 value
)
106 return i2c_smbus_write_word_data(client
, command
, swab16(value
));
109 /* Returns the number of read bytes */
110 extern s32
i2c_smbus_read_block_data(const struct i2c_client
*client
,
111 u8 command
, u8
*values
);
112 extern s32
i2c_smbus_write_block_data(const struct i2c_client
*client
,
113 u8 command
, u8 length
, const u8
*values
);
114 /* Returns the number of read bytes */
115 extern s32
i2c_smbus_read_i2c_block_data(const struct i2c_client
*client
,
116 u8 command
, u8 length
, u8
*values
);
117 extern s32
i2c_smbus_write_i2c_block_data(const struct i2c_client
*client
,
118 u8 command
, u8 length
,
123 * struct i2c_driver - represent an I2C device driver
124 * @class: What kind of i2c device we instantiate (for detect)
125 * @attach_adapter: Callback for bus addition (deprecated)
126 * @detach_adapter: Callback for bus removal (deprecated)
127 * @probe: Callback for device binding
128 * @remove: Callback for device unbinding
129 * @shutdown: Callback for device shutdown
130 * @suspend: Callback for device suspend
131 * @resume: Callback for device resume
132 * @alert: Alert callback, for example for the SMBus alert protocol
133 * @command: Callback for bus-wide signaling (optional)
134 * @driver: Device driver model driver
135 * @id_table: List of I2C devices supported by this driver
136 * @detect: Callback for device detection
137 * @address_list: The I2C addresses to probe (for detect)
138 * @clients: List of detected clients we created (for i2c-core use only)
140 * The driver.owner field should be set to the module owner of this driver.
141 * The driver.name field should be set to the name of this driver.
143 * For automatic device detection, both @detect and @address_data must
144 * be defined. @class should also be set, otherwise only devices forced
145 * with module parameters will be created. The detect function must
146 * fill at least the name field of the i2c_board_info structure it is
147 * handed upon successful detection, and possibly also the flags field.
149 * If @detect is missing, the driver will still work fine for enumerated
150 * devices. Detected devices simply won't be supported. This is expected
151 * for the many I2C/SMBus devices which can't be detected reliably, and
152 * the ones which can always be enumerated in practice.
154 * The i2c_client structure which is handed to the @detect callback is
155 * not a real i2c_client. It is initialized just enough so that you can
156 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
157 * else with it. In particular, calling dev_dbg and friends on it is
163 /* Notifies the driver that a new bus has appeared or is about to be
164 * removed. You should avoid using this, it will be removed in a
167 int (*attach_adapter
)(struct i2c_adapter
*) __deprecated
;
168 int (*detach_adapter
)(struct i2c_adapter
*) __deprecated
;
170 /* Standard driver model interfaces */
171 int (*probe
)(struct i2c_client
*, const struct i2c_device_id
*);
172 int (*remove
)(struct i2c_client
*);
174 /* driver model interfaces that don't relate to enumeration */
175 void (*shutdown
)(struct i2c_client
*);
176 int (*suspend
)(struct i2c_client
*, pm_message_t mesg
);
177 int (*resume
)(struct i2c_client
*);
179 /* Alert callback, for example for the SMBus alert protocol.
180 * The format and meaning of the data value depends on the protocol.
181 * For the SMBus alert protocol, there is a single bit of data passed
182 * as the alert response's low bit ("event flag").
184 void (*alert
)(struct i2c_client
*, unsigned int data
);
186 /* a ioctl like command that can be used to perform specific functions
189 int (*command
)(struct i2c_client
*client
, unsigned int cmd
, void *arg
);
191 struct device_driver driver
;
192 const struct i2c_device_id
*id_table
;
194 /* Device detection callback for automatic device creation */
195 int (*detect
)(struct i2c_client
*, struct i2c_board_info
*);
196 const unsigned short *address_list
;
197 struct list_head clients
;
199 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
202 * struct i2c_client - represent an I2C slave device
203 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
204 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
205 * @addr: Address used on the I2C bus connected to the parent adapter.
206 * @name: Indicates the type of the device, usually a chip name that's
207 * generic enough to hide second-sourcing and compatible revisions.
208 * @adapter: manages the bus segment hosting this I2C device
209 * @driver: device's driver, hence pointer to access routines
210 * @dev: Driver model device node for the slave.
211 * @irq: indicates the IRQ generated by this device (if any)
212 * @detected: member of an i2c_driver.clients list or i2c-core's
213 * userspace_devices list
215 * An i2c_client identifies a single device (i.e. chip) connected to an
216 * i2c bus. The behaviour exposed to Linux is defined by the driver
217 * managing the device.
220 unsigned short flags
; /* div., see below */
221 unsigned short addr
; /* chip address - NOTE: 7bit */
222 /* addresses are stored in the */
224 char name
[I2C_NAME_SIZE
];
225 struct i2c_adapter
*adapter
; /* the adapter we sit on */
226 struct i2c_driver
*driver
; /* and our access routines */
227 struct device dev
; /* the device structure */
228 int irq
; /* irq issued by device */
229 struct list_head detected
;
231 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
233 extern struct i2c_client
*i2c_verify_client(struct device
*dev
);
235 static inline struct i2c_client
*kobj_to_i2c_client(struct kobject
*kobj
)
237 struct device
* const dev
= container_of(kobj
, struct device
, kobj
);
238 return to_i2c_client(dev
);
241 static inline void *i2c_get_clientdata(const struct i2c_client
*dev
)
243 return dev_get_drvdata(&dev
->dev
);
246 static inline void i2c_set_clientdata(struct i2c_client
*dev
, void *data
)
248 dev_set_drvdata(&dev
->dev
, data
);
252 * struct i2c_board_info - template for device creation
253 * @type: chip type, to initialize i2c_client.name
254 * @flags: to initialize i2c_client.flags
255 * @addr: stored in i2c_client.addr
256 * @platform_data: stored in i2c_client.dev.platform_data
257 * @archdata: copied into i2c_client.dev.archdata
258 * @of_node: pointer to OpenFirmware device node
259 * @irq: stored in i2c_client.irq
261 * I2C doesn't actually support hardware probing, although controllers and
262 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
263 * a device at a given address. Drivers commonly need more information than
264 * that, such as chip type, configuration, associated IRQ, and so on.
266 * i2c_board_info is used to build tables of information listing I2C devices
267 * that are present. This information is used to grow the driver model tree.
268 * For mainboards this is done statically using i2c_register_board_info();
269 * bus numbers identify adapters that aren't yet available. For add-on boards,
270 * i2c_new_device() does this dynamically with the adapter already known.
272 struct i2c_board_info
{
273 char type
[I2C_NAME_SIZE
];
274 unsigned short flags
;
277 struct dev_archdata
*archdata
;
278 struct device_node
*of_node
;
283 * I2C_BOARD_INFO - macro used to list an i2c device and its address
284 * @dev_type: identifies the device type
285 * @dev_addr: the device's address on the bus.
287 * This macro initializes essential fields of a struct i2c_board_info,
288 * declaring what has been provided on a particular board. Optional
289 * fields (such as associated irq, or device-specific platform_data)
290 * are provided using conventional syntax.
292 #define I2C_BOARD_INFO(dev_type, dev_addr) \
293 .type = dev_type, .addr = (dev_addr)
296 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
297 /* Add-on boards should register/unregister their devices; e.g. a board
298 * with integrated I2C, a config eeprom, sensors, and a codec that's
299 * used in conjunction with the primary hardware.
301 extern struct i2c_client
*
302 i2c_new_device(struct i2c_adapter
*adap
, struct i2c_board_info
const *info
);
304 /* If you don't know the exact address of an I2C device, use this variant
305 * instead, which can probe for device presence in a list of possible
306 * addresses. The "probe" callback function is optional. If it is provided,
307 * it must return 1 on successful probe, 0 otherwise. If it is not provided,
308 * a default probing method is used.
310 extern struct i2c_client
*
311 i2c_new_probed_device(struct i2c_adapter
*adap
,
312 struct i2c_board_info
*info
,
313 unsigned short const *addr_list
,
314 int (*probe
)(struct i2c_adapter
*, unsigned short addr
));
316 /* Common custom probe functions */
317 extern int i2c_probe_func_quick_read(struct i2c_adapter
*, unsigned short addr
);
319 /* For devices that use several addresses, use i2c_new_dummy() to make
320 * client handles for the extra addresses.
322 extern struct i2c_client
*
323 i2c_new_dummy(struct i2c_adapter
*adap
, u16 address
);
325 extern void i2c_unregister_device(struct i2c_client
*);
328 /* Mainboard arch_initcall() code should register all its I2C devices.
329 * This is done at arch_initcall time, before declaring any i2c adapters.
330 * Modules for add-on boards must use other calls.
332 #ifdef CONFIG_I2C_BOARDINFO
334 i2c_register_board_info(int busnum
, struct i2c_board_info
const *info
,
338 i2c_register_board_info(int busnum
, struct i2c_board_info
const *info
,
343 #endif /* I2C_BOARDINFO */
346 * The following structs are for those who like to implement new bus drivers:
347 * i2c_algorithm is the interface to a class of hardware solutions which can
348 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
349 * to name two of the most common.
351 struct i2c_algorithm
{
352 /* If an adapter algorithm can't do I2C-level access, set master_xfer
353 to NULL. If an adapter algorithm can do SMBus access, set
354 smbus_xfer. If set to NULL, the SMBus protocol is simulated
355 using common I2C messages */
356 /* master_xfer should return the number of messages successfully
357 processed, or a negative value on error */
358 int (*master_xfer
)(struct i2c_adapter
*adap
, struct i2c_msg
*msgs
,
360 int (*smbus_xfer
) (struct i2c_adapter
*adap
, u16 addr
,
361 unsigned short flags
, char read_write
,
362 u8 command
, int size
, union i2c_smbus_data
*data
);
364 /* To determine what the adapter supports */
365 u32 (*functionality
) (struct i2c_adapter
*);
369 * i2c_adapter is the structure used to identify a physical i2c bus along
370 * with the access algorithms necessary to access it.
373 struct module
*owner
;
374 unsigned int class; /* classes to allow probing for */
375 const struct i2c_algorithm
*algo
; /* the algorithm to access the bus */
378 /* data fields that are valid for all devices */
379 struct rt_mutex bus_lock
;
381 int timeout
; /* in jiffies */
383 struct device dev
; /* the adapter device */
387 struct completion dev_released
;
389 struct mutex userspace_clients_lock
;
390 struct list_head userspace_clients
;
392 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
394 static inline void *i2c_get_adapdata(const struct i2c_adapter
*dev
)
396 return dev_get_drvdata(&dev
->dev
);
399 static inline void i2c_set_adapdata(struct i2c_adapter
*dev
, void *data
)
401 dev_set_drvdata(&dev
->dev
, data
);
404 static inline struct i2c_adapter
*
405 i2c_parent_is_i2c_adapter(const struct i2c_adapter
*adapter
)
407 struct device
*parent
= adapter
->dev
.parent
;
409 if (parent
!= NULL
&& parent
->type
== &i2c_adapter_type
)
410 return to_i2c_adapter(parent
);
415 int i2c_for_each_dev(void *data
, int (*fn
)(struct device
*, void *));
417 /* Adapter locking functions, exported for shared pin cases */
418 void i2c_lock_adapter(struct i2c_adapter
*);
419 void i2c_unlock_adapter(struct i2c_adapter
*);
421 /*flags for the client struct: */
422 #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
423 #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
424 /* Must equal I2C_M_TEN below */
425 #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
427 /* i2c adapter classes (bitmask) */
428 #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
429 #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
430 #define I2C_CLASS_SPD (1<<7) /* Memory modules */
432 /* Internal numbers to terminate lists */
433 #define I2C_CLIENT_END 0xfffeU
435 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
436 #define I2C_ADDRS(addr, addrs...) \
437 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
440 /* ----- functions exported by i2c.o */
444 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
445 extern int i2c_add_adapter(struct i2c_adapter
*);
446 extern int i2c_del_adapter(struct i2c_adapter
*);
447 extern int i2c_add_numbered_adapter(struct i2c_adapter
*);
449 extern int i2c_register_driver(struct module
*, struct i2c_driver
*);
450 extern void i2c_del_driver(struct i2c_driver
*);
452 /* use a define to avoid include chaining to get THIS_MODULE */
453 #define i2c_add_driver(driver) \
454 i2c_register_driver(THIS_MODULE, driver)
456 extern struct i2c_client
*i2c_use_client(struct i2c_client
*client
);
457 extern void i2c_release_client(struct i2c_client
*client
);
459 /* call the i2c_client->command() of all attached clients with
460 * the given arguments */
461 extern void i2c_clients_command(struct i2c_adapter
*adap
,
462 unsigned int cmd
, void *arg
);
464 extern struct i2c_adapter
*i2c_get_adapter(int nr
);
465 extern void i2c_put_adapter(struct i2c_adapter
*adap
);
468 /* Return the functionality mask */
469 static inline u32
i2c_get_functionality(struct i2c_adapter
*adap
)
471 return adap
->algo
->functionality(adap
);
474 /* Return 1 if adapter supports everything we need, 0 if not. */
475 static inline int i2c_check_functionality(struct i2c_adapter
*adap
, u32 func
)
477 return (func
& i2c_get_functionality(adap
)) == func
;
480 /* Return the adapter number for a specific adapter */
481 static inline int i2c_adapter_id(struct i2c_adapter
*adap
)
486 #endif /* __KERNEL__ */
489 * struct i2c_msg - an I2C transaction segment beginning with START
490 * @addr: Slave address, either seven or ten bits. When this is a ten
491 * bit address, I2C_M_TEN must be set in @flags and the adapter
492 * must support I2C_FUNC_10BIT_ADDR.
493 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
494 * provided unless the adapter exported the relevant I2C_FUNC_*
495 * flags through i2c_check_functionality().
496 * @len: Number of data bytes in @buf being read from or written to the
497 * I2C slave address. For read transactions where I2C_M_RECV_LEN
498 * is set, the caller guarantees that this buffer can hold up to
499 * 32 bytes in addition to the initial length byte sent by the
500 * slave (plus, if used, the SMBus PEC); and this value will be
501 * incremented by the number of block data bytes received.
502 * @buf: The buffer into which data is read, or from which it's written.
504 * An i2c_msg is the low level representation of one segment of an I2C
505 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
506 * to userspace from i2c-dev, and to I2C adapter drivers through the
507 * @i2c_adapter.@master_xfer() method.
509 * Except when I2C "protocol mangling" is used, all I2C adapters implement
510 * the standard rules for I2C transactions. Each transaction begins with a
511 * START. That is followed by the slave address, and a bit encoding read
512 * versus write. Then follow all the data bytes, possibly including a byte
513 * with SMBus PEC. The transfer terminates with a NAK, or when all those
514 * bytes have been transferred and ACKed. If this is the last message in a
515 * group, it is followed by a STOP. Otherwise it is followed by the next
516 * @i2c_msg transaction segment, beginning with a (repeated) START.
518 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
519 * passing certain @flags may have changed those standard protocol behaviors.
520 * Those flags are only for use with broken/nonconforming slaves, and with
521 * adapters which are known to support the specific mangling options they
522 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
525 __u16 addr
; /* slave address */
527 #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
528 #define I2C_M_RD 0x0001 /* read data, from slave to master */
529 #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
530 #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
531 #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
532 #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
533 #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
534 __u16 len
; /* msg length */
535 __u8
*buf
; /* pointer to msg data */
538 /* To determine what functionality is present */
540 #define I2C_FUNC_I2C 0x00000001
541 #define I2C_FUNC_10BIT_ADDR 0x00000002
542 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
543 #define I2C_FUNC_SMBUS_PEC 0x00000008
544 #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
545 #define I2C_FUNC_SMBUS_QUICK 0x00010000
546 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
547 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
548 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
549 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
550 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
551 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
552 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
553 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
554 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
555 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
556 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
558 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
559 I2C_FUNC_SMBUS_WRITE_BYTE)
560 #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
561 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
562 #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
563 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
564 #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
565 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
566 #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
567 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
569 #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
570 I2C_FUNC_SMBUS_BYTE | \
571 I2C_FUNC_SMBUS_BYTE_DATA | \
572 I2C_FUNC_SMBUS_WORD_DATA | \
573 I2C_FUNC_SMBUS_PROC_CALL | \
574 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
575 I2C_FUNC_SMBUS_I2C_BLOCK | \
579 * Data for SMBus Messages
581 #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
582 union i2c_smbus_data
{
585 __u8 block
[I2C_SMBUS_BLOCK_MAX
+ 2]; /* block[0] is used for length */
586 /* and one more for user-space compatibility */
589 /* i2c_smbus_xfer read or write markers */
590 #define I2C_SMBUS_READ 1
591 #define I2C_SMBUS_WRITE 0
593 /* SMBus transaction types (size parameter in the above functions)
594 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
595 #define I2C_SMBUS_QUICK 0
596 #define I2C_SMBUS_BYTE 1
597 #define I2C_SMBUS_BYTE_DATA 2
598 #define I2C_SMBUS_WORD_DATA 3
599 #define I2C_SMBUS_PROC_CALL 4
600 #define I2C_SMBUS_BLOCK_DATA 5
601 #define I2C_SMBUS_I2C_BLOCK_BROKEN 6
602 #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
603 #define I2C_SMBUS_I2C_BLOCK_DATA 8
605 #endif /* _LINUX_I2C_H */