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
38 extern struct bus_type i2c_bus_type;
39 extern struct device_type i2c_adapter_type;
40
41 /* --- General options ------------------------------------------------ */
42
43 struct i2c_msg;
44 struct i2c_algorithm;
45 struct i2c_adapter;
46 struct i2c_client;
47 struct i2c_driver;
48 union i2c_smbus_data;
49 struct i2c_board_info;
50
51 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
52 /*
53 * The master routines are the ones normally used to transmit data to devices
54 * on a bus (or read from them). Apart from two basic transfer functions to
55 * transmit one message at a time, a more complex version can be used to
56 * transmit an arbitrary number of messages without interruption.
57 * @count must be be less than 64k since msg.len is u16.
58 */
59 extern int i2c_master_send(const struct i2c_client *client, const char *buf,
60 int count);
61 extern int i2c_master_recv(const struct i2c_client *client, char *buf,
62 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(const struct i2c_client *client);
82 extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
83 extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client,
84 u8 command);
85 extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client,
86 u8 command, u8 value);
87 extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
88 u8 command);
89 extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
90 u8 command, u16 value);
91 /* Returns the number of read bytes */
92 extern s32 i2c_smbus_read_block_data(const struct i2c_client *client,
93 u8 command, u8 *values);
94 extern s32 i2c_smbus_write_block_data(const struct i2c_client *client,
95 u8 command, u8 length, const u8 *values);
96 /* Returns the number of read bytes */
97 extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client,
98 u8 command, u8 length, u8 *values);
99 extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client,
100 u8 command, u8 length,
101 const u8 *values);
102 #endif /* I2C */
103
104 /**
105 * struct i2c_driver - represent an I2C device driver
106 * @class: What kind of i2c device we instantiate (for detect)
107 * @attach_adapter: Callback for bus addition (deprecated)
108 * @detach_adapter: Callback for bus removal (deprecated)
109 * @probe: Callback for device binding
110 * @remove: Callback for device unbinding
111 * @shutdown: Callback for device shutdown
112 * @suspend: Callback for device suspend
113 * @resume: Callback for device resume
114 * @alert: Alert callback, for example for the SMBus alert protocol
115 * @command: Callback for bus-wide signaling (optional)
116 * @driver: Device driver model driver
117 * @id_table: List of I2C devices supported by this driver
118 * @detect: Callback for device detection
119 * @address_list: The I2C addresses to probe (for detect)
120 * @clients: List of detected clients we created (for i2c-core use only)
121 *
122 * The driver.owner field should be set to the module owner of this driver.
123 * The driver.name field should be set to the name of this driver.
124 *
125 * For automatic device detection, both @detect and @address_data must
126 * be defined. @class should also be set, otherwise only devices forced
127 * with module parameters will be created. The detect function must
128 * fill at least the name field of the i2c_board_info structure it is
129 * handed upon successful detection, and possibly also the flags field.
130 *
131 * If @detect is missing, the driver will still work fine for enumerated
132 * devices. Detected devices simply won't be supported. This is expected
133 * for the many I2C/SMBus devices which can't be detected reliably, and
134 * the ones which can always be enumerated in practice.
135 *
136 * The i2c_client structure which is handed to the @detect callback is
137 * not a real i2c_client. It is initialized just enough so that you can
138 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
139 * else with it. In particular, calling dev_dbg and friends on it is
140 * not allowed.
141 */
142 struct i2c_driver {
143 unsigned int class;
144
145 /* Notifies the driver that a new bus has appeared or is about to be
146 * removed. You should avoid using this, it will be removed in a
147 * near future.
148 */
149 int (*attach_adapter)(struct i2c_adapter *) __deprecated;
150 int (*detach_adapter)(struct i2c_adapter *) __deprecated;
151
152 /* Standard driver model interfaces */
153 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
154 int (*remove)(struct i2c_client *);
155
156 /* driver model interfaces that don't relate to enumeration */
157 void (*shutdown)(struct i2c_client *);
158 int (*suspend)(struct i2c_client *, pm_message_t mesg);
159 int (*resume)(struct i2c_client *);
160
161 /* Alert callback, for example for the SMBus alert protocol.
162 * The format and meaning of the data value depends on the protocol.
163 * For the SMBus alert protocol, there is a single bit of data passed
164 * as the alert response's low bit ("event flag").
165 */
166 void (*alert)(struct i2c_client *, unsigned int data);
167
168 /* a ioctl like command that can be used to perform specific functions
169 * with the device.
170 */
171 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
172
173 struct device_driver driver;
174 const struct i2c_device_id *id_table;
175
176 /* Device detection callback for automatic device creation */
177 int (*detect)(struct i2c_client *, struct i2c_board_info *);
178 const unsigned short *address_list;
179 struct list_head clients;
180 };
181 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
182
183 /**
184 * struct i2c_client - represent an I2C slave device
185 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
186 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
187 * @addr: Address used on the I2C bus connected to the parent adapter.
188 * @name: Indicates the type of the device, usually a chip name that's
189 * generic enough to hide second-sourcing and compatible revisions.
190 * @adapter: manages the bus segment hosting this I2C device
191 * @driver: device's driver, hence pointer to access routines
192 * @dev: Driver model device node for the slave.
193 * @irq: indicates the IRQ generated by this device (if any)
194 * @detected: member of an i2c_driver.clients list or i2c-core's
195 * userspace_devices list
196 *
197 * An i2c_client identifies a single device (i.e. chip) connected to an
198 * i2c bus. The behaviour exposed to Linux is defined by the driver
199 * managing the device.
200 */
201 struct i2c_client {
202 unsigned short flags; /* div., see below */
203 unsigned short addr; /* chip address - NOTE: 7bit */
204 /* addresses are stored in the */
205 /* _LOWER_ 7 bits */
206 char name[I2C_NAME_SIZE];
207 struct i2c_adapter *adapter; /* the adapter we sit on */
208 struct i2c_driver *driver; /* and our access routines */
209 struct device dev; /* the device structure */
210 int irq; /* irq issued by device */
211 struct list_head detected;
212 };
213 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
214
215 extern struct i2c_client *i2c_verify_client(struct device *dev);
216
kobj_to_i2c_client(struct kobject * kobj)217 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
218 {
219 struct device * const dev = container_of(kobj, struct device, kobj);
220 return to_i2c_client(dev);
221 }
222
i2c_get_clientdata(const struct i2c_client * dev)223 static inline void *i2c_get_clientdata(const struct i2c_client *dev)
224 {
225 return dev_get_drvdata(&dev->dev);
226 }
227
i2c_set_clientdata(struct i2c_client * dev,void * data)228 static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
229 {
230 dev_set_drvdata(&dev->dev, data);
231 }
232
233 /**
234 * struct i2c_board_info - template for device creation
235 * @type: chip type, to initialize i2c_client.name
236 * @flags: to initialize i2c_client.flags
237 * @addr: stored in i2c_client.addr
238 * @platform_data: stored in i2c_client.dev.platform_data
239 * @archdata: copied into i2c_client.dev.archdata
240 * @of_node: pointer to OpenFirmware device node
241 * @irq: stored in i2c_client.irq
242 *
243 * I2C doesn't actually support hardware probing, although controllers and
244 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
245 * a device at a given address. Drivers commonly need more information than
246 * that, such as chip type, configuration, associated IRQ, and so on.
247 *
248 * i2c_board_info is used to build tables of information listing I2C devices
249 * that are present. This information is used to grow the driver model tree.
250 * For mainboards this is done statically using i2c_register_board_info();
251 * bus numbers identify adapters that aren't yet available. For add-on boards,
252 * i2c_new_device() does this dynamically with the adapter already known.
253 */
254 struct i2c_board_info {
255 char type[I2C_NAME_SIZE];
256 unsigned short flags;
257 unsigned short addr;
258 void *platform_data;
259 struct dev_archdata *archdata;
260 struct device_node *of_node;
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
i2c_register_board_info(int busnum,struct i2c_board_info const * info,unsigned n)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 class; /* classes to allow probing for */
357 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
358 void *algo_data;
359
360 /* data fields that are valid for all devices */
361 struct rt_mutex bus_lock;
362
363 int timeout; /* in jiffies */
364 int retries;
365 struct device dev; /* the adapter device */
366
367 int nr;
368 char name[48];
369 struct completion dev_released;
370
371 struct mutex userspace_clients_lock;
372 struct list_head userspace_clients;
373 };
374 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
375
i2c_get_adapdata(const struct i2c_adapter * dev)376 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
377 {
378 return dev_get_drvdata(&dev->dev);
379 }
380
i2c_set_adapdata(struct i2c_adapter * dev,void * data)381 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
382 {
383 dev_set_drvdata(&dev->dev, data);
384 }
385
386 static inline struct i2c_adapter *
i2c_parent_is_i2c_adapter(const struct i2c_adapter * adapter)387 i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
388 {
389 struct device *parent = adapter->dev.parent;
390
391 if (parent != NULL && parent->type == &i2c_adapter_type)
392 return to_i2c_adapter(parent);
393 else
394 return NULL;
395 }
396
397 int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
398
399 /* Adapter locking functions, exported for shared pin cases */
400 void i2c_lock_adapter(struct i2c_adapter *);
401 void i2c_unlock_adapter(struct i2c_adapter *);
402
403 /*flags for the client struct: */
404 #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
405 #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
406 /* Must equal I2C_M_TEN below */
407 #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
408
409 /* i2c adapter classes (bitmask) */
410 #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
411 #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
412 #define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
413
414 /* Internal numbers to terminate lists */
415 #define I2C_CLIENT_END 0xfffeU
416
417 /* The numbers to use to set I2C bus address */
418 #define ANY_I2C_BUS 0xffff
419
420 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
421 #define I2C_ADDRS(addr, addrs...) \
422 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
423
424
425 /* ----- functions exported by i2c.o */
426
427 /* administration...
428 */
429 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
430 extern int i2c_add_adapter(struct i2c_adapter *);
431 extern int i2c_del_adapter(struct i2c_adapter *);
432 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
433
434 extern int i2c_register_driver(struct module *, struct i2c_driver *);
435 extern void i2c_del_driver(struct i2c_driver *);
436
i2c_add_driver(struct i2c_driver * driver)437 static inline int i2c_add_driver(struct i2c_driver *driver)
438 {
439 return i2c_register_driver(THIS_MODULE, driver);
440 }
441
442 extern struct i2c_client *i2c_use_client(struct i2c_client *client);
443 extern void i2c_release_client(struct i2c_client *client);
444
445 /* call the i2c_client->command() of all attached clients with
446 * the given arguments */
447 extern void i2c_clients_command(struct i2c_adapter *adap,
448 unsigned int cmd, void *arg);
449
450 extern struct i2c_adapter *i2c_get_adapter(int nr);
451 extern void i2c_put_adapter(struct i2c_adapter *adap);
452
453
454 /* Return the functionality mask */
i2c_get_functionality(struct i2c_adapter * adap)455 static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
456 {
457 return adap->algo->functionality(adap);
458 }
459
460 /* Return 1 if adapter supports everything we need, 0 if not. */
i2c_check_functionality(struct i2c_adapter * adap,u32 func)461 static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
462 {
463 return (func & i2c_get_functionality(adap)) == func;
464 }
465
466 /* Return the adapter number for a specific adapter */
i2c_adapter_id(struct i2c_adapter * adap)467 static inline int i2c_adapter_id(struct i2c_adapter *adap)
468 {
469 return adap->nr;
470 }
471 #endif /* I2C */
472 #endif /* __KERNEL__ */
473
474 /**
475 * struct i2c_msg - an I2C transaction segment beginning with START
476 * @addr: Slave address, either seven or ten bits. When this is a ten
477 * bit address, I2C_M_TEN must be set in @flags and the adapter
478 * must support I2C_FUNC_10BIT_ADDR.
479 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
480 * provided unless the adapter exported the relevant I2C_FUNC_*
481 * flags through i2c_check_functionality().
482 * @len: Number of data bytes in @buf being read from or written to the
483 * I2C slave address. For read transactions where I2C_M_RECV_LEN
484 * is set, the caller guarantees that this buffer can hold up to
485 * 32 bytes in addition to the initial length byte sent by the
486 * slave (plus, if used, the SMBus PEC); and this value will be
487 * incremented by the number of block data bytes received.
488 * @buf: The buffer into which data is read, or from which it's written.
489 *
490 * An i2c_msg is the low level representation of one segment of an I2C
491 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
492 * to userspace from i2c-dev, and to I2C adapter drivers through the
493 * @i2c_adapter.@master_xfer() method.
494 *
495 * Except when I2C "protocol mangling" is used, all I2C adapters implement
496 * the standard rules for I2C transactions. Each transaction begins with a
497 * START. That is followed by the slave address, and a bit encoding read
498 * versus write. Then follow all the data bytes, possibly including a byte
499 * with SMBus PEC. The transfer terminates with a NAK, or when all those
500 * bytes have been transferred and ACKed. If this is the last message in a
501 * group, it is followed by a STOP. Otherwise it is followed by the next
502 * @i2c_msg transaction segment, beginning with a (repeated) START.
503 *
504 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
505 * passing certain @flags may have changed those standard protocol behaviors.
506 * Those flags are only for use with broken/nonconforming slaves, and with
507 * adapters which are known to support the specific mangling options they
508 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
509 */
510 struct i2c_msg {
511 __u16 addr; /* slave address */
512 __u16 flags;
513 #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
514 #define I2C_M_RD 0x0001 /* read data, from slave to master */
515 #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
516 #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
517 #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
518 #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
519 #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
520 __u16 len; /* msg length */
521 __u8 *buf; /* pointer to msg data */
522 };
523
524 /* To determine what functionality is present */
525
526 #define I2C_FUNC_I2C 0x00000001
527 #define I2C_FUNC_10BIT_ADDR 0x00000002
528 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
529 #define I2C_FUNC_SMBUS_PEC 0x00000008
530 #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
531 #define I2C_FUNC_SMBUS_QUICK 0x00010000
532 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
533 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
534 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
535 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
536 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
537 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
538 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
539 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
540 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
541 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
542 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
543
544 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
545 I2C_FUNC_SMBUS_WRITE_BYTE)
546 #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
547 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
548 #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
549 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
550 #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
551 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
552 #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
553 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
554
555 #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
556 I2C_FUNC_SMBUS_BYTE | \
557 I2C_FUNC_SMBUS_BYTE_DATA | \
558 I2C_FUNC_SMBUS_WORD_DATA | \
559 I2C_FUNC_SMBUS_PROC_CALL | \
560 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
561 I2C_FUNC_SMBUS_I2C_BLOCK | \
562 I2C_FUNC_SMBUS_PEC)
563
564 /*
565 * Data for SMBus Messages
566 */
567 #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
568 union i2c_smbus_data {
569 __u8 byte;
570 __u16 word;
571 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
572 /* and one more for user-space compatibility */
573 };
574
575 /* i2c_smbus_xfer read or write markers */
576 #define I2C_SMBUS_READ 1
577 #define I2C_SMBUS_WRITE 0
578
579 /* SMBus transaction types (size parameter in the above functions)
580 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
581 #define I2C_SMBUS_QUICK 0
582 #define I2C_SMBUS_BYTE 1
583 #define I2C_SMBUS_BYTE_DATA 2
584 #define I2C_SMBUS_WORD_DATA 3
585 #define I2C_SMBUS_PROC_CALL 4
586 #define I2C_SMBUS_BLOCK_DATA 5
587 #define I2C_SMBUS_I2C_BLOCK_BROKEN 6
588 #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
589 #define I2C_SMBUS_I2C_BLOCK_DATA 8
590
591 #endif /* _LINUX_I2C_H */
592