dm: factor out max_io_len_target_boundary
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / linux / i2c.h
blob38dd4025aa4e47b9da99570e7f60ea72003ba600
1 /* ------------------------------------------------------------------------- */
2 /* */
3 /* i2c.h - definitions for the i2c-bus interface */
4 /* */
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> */
26 #ifndef _LINUX_I2C_H
27 #define _LINUX_I2C_H
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 */
39 extern struct bus_type i2c_bus_type;
41 /* --- General options ------------------------------------------------ */
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;
51 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
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.
59 extern int i2c_master_send(struct i2c_client *client, const char *buf,
60 int count);
61 extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
63 /* Transfer num messages.
65 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
66 int num);
68 /* This is the very generalized SMBus access routine. You probably do not
69 want to use this, though; one of the functions below may be much easier,
70 and probably just as fast.
71 Note that we use i2c_adapter here, because you do not need a specific
72 smbus adapter to call this function. */
73 extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
74 unsigned short flags, char read_write, u8 command,
75 int size, union i2c_smbus_data *data);
77 /* Now follow the 'nice' access routines. These also document the calling
78 conventions of i2c_smbus_xfer. */
80 extern s32 i2c_smbus_read_byte(struct i2c_client *client);
81 extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value);
82 extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);
83 extern s32 i2c_smbus_write_byte_data(struct i2c_client *client,
84 u8 command, u8 value);
85 extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
86 extern s32 i2c_smbus_write_word_data(struct i2c_client *client,
87 u8 command, u16 value);
88 /* Returns the number of read bytes */
89 extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
90 u8 command, u8 *values);
91 extern s32 i2c_smbus_write_block_data(struct i2c_client *client,
92 u8 command, u8 length, const u8 *values);
93 /* Returns the number of read bytes */
94 extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client,
95 u8 command, u8 length, u8 *values);
96 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client,
97 u8 command, u8 length,
98 const u8 *values);
99 #endif /* I2C */
102 * struct i2c_driver - represent an I2C device driver
103 * @class: What kind of i2c device we instantiate (for detect)
104 * @attach_adapter: Callback for bus addition (for legacy drivers)
105 * @detach_adapter: Callback for bus removal (for legacy drivers)
106 * @probe: Callback for device binding
107 * @remove: Callback for device unbinding
108 * @shutdown: Callback for device shutdown
109 * @suspend: Callback for device suspend
110 * @resume: Callback for device resume
111 * @alert: Alert callback, for example for the SMBus alert protocol
112 * @command: Callback for bus-wide signaling (optional)
113 * @driver: Device driver model driver
114 * @id_table: List of I2C devices supported by this driver
115 * @detect: Callback for device detection
116 * @address_list: The I2C addresses to probe (for detect)
117 * @clients: List of detected clients we created (for i2c-core use only)
119 * The driver.owner field should be set to the module owner of this driver.
120 * The driver.name field should be set to the name of this driver.
122 * For automatic device detection, both @detect and @address_data must
123 * be defined. @class should also be set, otherwise only devices forced
124 * with module parameters will be created. The detect function must
125 * fill at least the name field of the i2c_board_info structure it is
126 * handed upon successful detection, and possibly also the flags field.
128 * If @detect is missing, the driver will still work fine for enumerated
129 * devices. Detected devices simply won't be supported. This is expected
130 * for the many I2C/SMBus devices which can't be detected reliably, and
131 * the ones which can always be enumerated in practice.
133 * The i2c_client structure which is handed to the @detect callback is
134 * not a real i2c_client. It is initialized just enough so that you can
135 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
136 * else with it. In particular, calling dev_dbg and friends on it is
137 * not allowed.
139 struct i2c_driver {
140 unsigned int class;
142 /* Notifies the driver that a new bus has appeared or is about to be
143 * removed. You should avoid using this if you can, it will probably
144 * be removed in a near future.
146 int (*attach_adapter)(struct i2c_adapter *);
147 int (*detach_adapter)(struct i2c_adapter *);
149 /* Standard driver model interfaces */
150 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
151 int (*remove)(struct i2c_client *);
153 /* driver model interfaces that don't relate to enumeration */
154 void (*shutdown)(struct i2c_client *);
155 int (*suspend)(struct i2c_client *, pm_message_t mesg);
156 int (*resume)(struct i2c_client *);
158 /* Alert callback, for example for the SMBus alert protocol.
159 * The format and meaning of the data value depends on the protocol.
160 * For the SMBus alert protocol, there is a single bit of data passed
161 * as the alert response's low bit ("event flag").
163 void (*alert)(struct i2c_client *, unsigned int data);
165 /* a ioctl like command that can be used to perform specific functions
166 * with the device.
168 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
170 struct device_driver driver;
171 const struct i2c_device_id *id_table;
173 /* Device detection callback for automatic device creation */
174 int (*detect)(struct i2c_client *, struct i2c_board_info *);
175 const unsigned short *address_list;
176 struct list_head clients;
178 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
181 * struct i2c_client - represent an I2C slave device
182 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
183 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
184 * @addr: Address used on the I2C bus connected to the parent adapter.
185 * @name: Indicates the type of the device, usually a chip name that's
186 * generic enough to hide second-sourcing and compatible revisions.
187 * @adapter: manages the bus segment hosting this I2C device
188 * @driver: device's driver, hence pointer to access routines
189 * @dev: Driver model device node for the slave.
190 * @irq: indicates the IRQ generated by this device (if any)
191 * @detected: member of an i2c_driver.clients list or i2c-core's
192 * userspace_devices list
194 * An i2c_client identifies a single device (i.e. chip) connected to an
195 * i2c bus. The behaviour exposed to Linux is defined by the driver
196 * managing the device.
198 struct i2c_client {
199 unsigned short flags; /* div., see below */
200 unsigned short addr; /* chip address - NOTE: 7bit */
201 /* addresses are stored in the */
202 /* _LOWER_ 7 bits */
203 char name[I2C_NAME_SIZE];
204 struct i2c_adapter *adapter; /* the adapter we sit on */
205 struct i2c_driver *driver; /* and our access routines */
206 struct device dev; /* the device structure */
207 int irq; /* irq issued by device */
208 struct list_head detected;
210 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
212 extern struct i2c_client *i2c_verify_client(struct device *dev);
214 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
216 struct device * const dev = container_of(kobj, struct device, kobj);
217 return to_i2c_client(dev);
220 static inline void *i2c_get_clientdata(const struct i2c_client *dev)
222 return dev_get_drvdata(&dev->dev);
225 static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
227 dev_set_drvdata(&dev->dev, data);
231 * struct i2c_board_info - template for device creation
232 * @type: chip type, to initialize i2c_client.name
233 * @flags: to initialize i2c_client.flags
234 * @addr: stored in i2c_client.addr
235 * @platform_data: stored in i2c_client.dev.platform_data
236 * @archdata: copied into i2c_client.dev.archdata
237 * @of_node: pointer to OpenFirmware device node
238 * @irq: stored in i2c_client.irq
240 * I2C doesn't actually support hardware probing, although controllers and
241 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
242 * a device at a given address. Drivers commonly need more information than
243 * that, such as chip type, configuration, associated IRQ, and so on.
245 * i2c_board_info is used to build tables of information listing I2C devices
246 * that are present. This information is used to grow the driver model tree.
247 * For mainboards this is done statically using i2c_register_board_info();
248 * bus numbers identify adapters that aren't yet available. For add-on boards,
249 * i2c_new_device() does this dynamically with the adapter already known.
251 struct i2c_board_info {
252 char type[I2C_NAME_SIZE];
253 unsigned short flags;
254 unsigned short addr;
255 void *platform_data;
256 struct dev_archdata *archdata;
257 #ifdef CONFIG_OF
258 struct device_node *of_node;
259 #endif
260 int irq;
264 * I2C_BOARD_INFO - macro used to list an i2c device and its address
265 * @dev_type: identifies the device type
266 * @dev_addr: the device's address on the bus.
268 * This macro initializes essential fields of a struct i2c_board_info,
269 * declaring what has been provided on a particular board. Optional
270 * fields (such as associated irq, or device-specific platform_data)
271 * are provided using conventional syntax.
273 #define I2C_BOARD_INFO(dev_type, dev_addr) \
274 .type = dev_type, .addr = (dev_addr)
277 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
278 /* Add-on boards should register/unregister their devices; e.g. a board
279 * with integrated I2C, a config eeprom, sensors, and a codec that's
280 * used in conjunction with the primary hardware.
282 extern struct i2c_client *
283 i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
285 /* If you don't know the exact address of an I2C device, use this variant
286 * instead, which can probe for device presence in a list of possible
287 * addresses.
289 extern struct i2c_client *
290 i2c_new_probed_device(struct i2c_adapter *adap,
291 struct i2c_board_info *info,
292 unsigned short const *addr_list);
294 /* For devices that use several addresses, use i2c_new_dummy() to make
295 * client handles for the extra addresses.
297 extern struct i2c_client *
298 i2c_new_dummy(struct i2c_adapter *adap, u16 address);
300 extern void i2c_unregister_device(struct i2c_client *);
301 #endif /* I2C */
303 /* Mainboard arch_initcall() code should register all its I2C devices.
304 * This is done at arch_initcall time, before declaring any i2c adapters.
305 * Modules for add-on boards must use other calls.
307 #ifdef CONFIG_I2C_BOARDINFO
308 extern int
309 i2c_register_board_info(int busnum, struct i2c_board_info const *info,
310 unsigned n);
311 #else
312 static inline int
313 i2c_register_board_info(int busnum, struct i2c_board_info const *info,
314 unsigned n)
316 return 0;
318 #endif /* I2C_BOARDINFO */
321 * The following structs are for those who like to implement new bus drivers:
322 * i2c_algorithm is the interface to a class of hardware solutions which can
323 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
324 * to name two of the most common.
326 struct i2c_algorithm {
327 /* If an adapter algorithm can't do I2C-level access, set master_xfer
328 to NULL. If an adapter algorithm can do SMBus access, set
329 smbus_xfer. If set to NULL, the SMBus protocol is simulated
330 using common I2C messages */
331 /* master_xfer should return the number of messages successfully
332 processed, or a negative value on error */
333 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
334 int num);
335 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
336 unsigned short flags, char read_write,
337 u8 command, int size, union i2c_smbus_data *data);
339 /* To determine what the adapter supports */
340 u32 (*functionality) (struct i2c_adapter *);
344 * i2c_adapter is the structure used to identify a physical i2c bus along
345 * with the access algorithms necessary to access it.
347 struct i2c_adapter {
348 struct module *owner;
349 unsigned int id;
350 unsigned int class; /* classes to allow probing for */
351 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
352 void *algo_data;
354 /* data fields that are valid for all devices */
355 struct rt_mutex bus_lock;
357 int timeout; /* in jiffies */
358 int retries;
359 struct device dev; /* the adapter device */
361 int nr;
362 char name[48];
363 struct completion dev_released;
365 struct list_head userspace_clients;
367 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
369 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
371 return dev_get_drvdata(&dev->dev);
374 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
376 dev_set_drvdata(&dev->dev, data);
380 * i2c_lock_adapter - Prevent access to an I2C bus segment
381 * @adapter: Target I2C bus segment
383 static inline void i2c_lock_adapter(struct i2c_adapter *adapter)
385 rt_mutex_lock(&adapter->bus_lock);
389 * i2c_unlock_adapter - Reauthorize access to an I2C bus segment
390 * @adapter: Target I2C bus segment
392 static inline void i2c_unlock_adapter(struct i2c_adapter *adapter)
394 rt_mutex_unlock(&adapter->bus_lock);
397 /*flags for the client struct: */
398 #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
399 #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
400 /* Must equal I2C_M_TEN below */
401 #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
403 /* i2c adapter classes (bitmask) */
404 #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
405 #define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
406 #define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
407 #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
408 #define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
410 /* Internal numbers to terminate lists */
411 #define I2C_CLIENT_END 0xfffeU
413 /* The numbers to use to set I2C bus address */
414 #define ANY_I2C_BUS 0xffff
416 /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
417 #define I2C_ADDRS(addr, addrs...) \
418 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
421 /* ----- functions exported by i2c.o */
423 /* administration...
425 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
426 extern int i2c_add_adapter(struct i2c_adapter *);
427 extern int i2c_del_adapter(struct i2c_adapter *);
428 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
430 extern int i2c_register_driver(struct module *, struct i2c_driver *);
431 extern void i2c_del_driver(struct i2c_driver *);
433 static inline int i2c_add_driver(struct i2c_driver *driver)
435 return i2c_register_driver(THIS_MODULE, driver);
438 extern struct i2c_client *i2c_use_client(struct i2c_client *client);
439 extern void i2c_release_client(struct i2c_client *client);
441 /* call the i2c_client->command() of all attached clients with
442 * the given arguments */
443 extern void i2c_clients_command(struct i2c_adapter *adap,
444 unsigned int cmd, void *arg);
446 extern struct i2c_adapter *i2c_get_adapter(int id);
447 extern void i2c_put_adapter(struct i2c_adapter *adap);
450 /* Return the functionality mask */
451 static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
453 return adap->algo->functionality(adap);
456 /* Return 1 if adapter supports everything we need, 0 if not. */
457 static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
459 return (func & i2c_get_functionality(adap)) == func;
462 /* Return the adapter number for a specific adapter */
463 static inline int i2c_adapter_id(struct i2c_adapter *adap)
465 return adap->nr;
467 #endif /* I2C */
468 #endif /* __KERNEL__ */
471 * struct i2c_msg - an I2C transaction segment beginning with START
472 * @addr: Slave address, either seven or ten bits. When this is a ten
473 * bit address, I2C_M_TEN must be set in @flags and the adapter
474 * must support I2C_FUNC_10BIT_ADDR.
475 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
476 * provided unless the adapter exported the relevant I2C_FUNC_*
477 * flags through i2c_check_functionality().
478 * @len: Number of data bytes in @buf being read from or written to the
479 * I2C slave address. For read transactions where I2C_M_RECV_LEN
480 * is set, the caller guarantees that this buffer can hold up to
481 * 32 bytes in addition to the initial length byte sent by the
482 * slave (plus, if used, the SMBus PEC); and this value will be
483 * incremented by the number of block data bytes received.
484 * @buf: The buffer into which data is read, or from which it's written.
486 * An i2c_msg is the low level representation of one segment of an I2C
487 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
488 * to userspace from i2c-dev, and to I2C adapter drivers through the
489 * @i2c_adapter.@master_xfer() method.
491 * Except when I2C "protocol mangling" is used, all I2C adapters implement
492 * the standard rules for I2C transactions. Each transaction begins with a
493 * START. That is followed by the slave address, and a bit encoding read
494 * versus write. Then follow all the data bytes, possibly including a byte
495 * with SMBus PEC. The transfer terminates with a NAK, or when all those
496 * bytes have been transferred and ACKed. If this is the last message in a
497 * group, it is followed by a STOP. Otherwise it is followed by the next
498 * @i2c_msg transaction segment, beginning with a (repeated) START.
500 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
501 * passing certain @flags may have changed those standard protocol behaviors.
502 * Those flags are only for use with broken/nonconforming slaves, and with
503 * adapters which are known to support the specific mangling options they
504 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
506 struct i2c_msg {
507 __u16 addr; /* slave address */
508 __u16 flags;
509 #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
510 #define I2C_M_RD 0x0001 /* read data, from slave to master */
511 #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
512 #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
513 #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
514 #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
515 #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
516 __u16 len; /* msg length */
517 __u8 *buf; /* pointer to msg data */
520 /* To determine what functionality is present */
522 #define I2C_FUNC_I2C 0x00000001
523 #define I2C_FUNC_10BIT_ADDR 0x00000002
524 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
525 #define I2C_FUNC_SMBUS_PEC 0x00000008
526 #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
527 #define I2C_FUNC_SMBUS_QUICK 0x00010000
528 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
529 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
530 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
531 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
532 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
533 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
534 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
535 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
536 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
537 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
538 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
540 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
541 I2C_FUNC_SMBUS_WRITE_BYTE)
542 #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
543 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
544 #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
545 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
546 #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
547 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
548 #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
549 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
551 #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
552 I2C_FUNC_SMBUS_BYTE | \
553 I2C_FUNC_SMBUS_BYTE_DATA | \
554 I2C_FUNC_SMBUS_WORD_DATA | \
555 I2C_FUNC_SMBUS_PROC_CALL | \
556 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
557 I2C_FUNC_SMBUS_I2C_BLOCK | \
558 I2C_FUNC_SMBUS_PEC)
561 * Data for SMBus Messages
563 #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
564 union i2c_smbus_data {
565 __u8 byte;
566 __u16 word;
567 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
568 /* and one more for user-space compatibility */
571 /* i2c_smbus_xfer read or write markers */
572 #define I2C_SMBUS_READ 1
573 #define I2C_SMBUS_WRITE 0
575 /* SMBus transaction types (size parameter in the above functions)
576 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
577 #define I2C_SMBUS_QUICK 0
578 #define I2C_SMBUS_BYTE 1
579 #define I2C_SMBUS_BYTE_DATA 2
580 #define I2C_SMBUS_WORD_DATA 3
581 #define I2C_SMBUS_PROC_CALL 4
582 #define I2C_SMBUS_BLOCK_DATA 5
583 #define I2C_SMBUS_I2C_BLOCK_BROKEN 6
584 #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
585 #define I2C_SMBUS_I2C_BLOCK_DATA 8
587 #endif /* _LINUX_I2C_H */