]> bbs.cooldavid.org Git - net-next-2.6.git/blame - include/linux/i2c.h
i2c: Drop unused I2C_CLASS_TV flags
[net-next-2.6.git] / include / linux / i2c.h
CommitLineData
1da177e4 1/* ------------------------------------------------------------------------- */
438d6c2c 2/* */
1da177e4 3/* i2c.h - definitions for the i2c-bus interface */
438d6c2c 4/* */
1da177e4
LT
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
a1b9298e 23/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
1da177e4
LT
24 Frodo Looijaard <frodol@dds.nl> */
25
1da177e4
LT
26#ifndef _LINUX_I2C_H
27#define _LINUX_I2C_H
28
1da177e4 29#include <linux/types.h>
438d6c2c 30#ifdef __KERNEL__
a1b9298e 31#include <linux/module.h>
1da177e4 32#include <linux/i2c-id.h>
a9d1b24d 33#include <linux/mod_devicetable.h>
1da177e4 34#include <linux/device.h> /* for struct device */
4e57b681 35#include <linux/sched.h> /* for completion */
5c085d36 36#include <linux/mutex.h>
d12d42f7 37#include <linux/of.h> /* for struct device_node */
1da177e4 38
e9ca9eb9 39extern struct bus_type i2c_bus_type;
0826374b 40extern struct device_type i2c_adapter_type;
e9ca9eb9 41
1da177e4
LT
42/* --- General options ------------------------------------------------ */
43
44struct i2c_msg;
45struct i2c_algorithm;
46struct i2c_adapter;
47struct i2c_client;
48struct i2c_driver;
1da177e4 49union i2c_smbus_data;
4735c98f 50struct i2c_board_info;
1da177e4 51
23af8400 52#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1da177e4
LT
53/*
54 * The master routines are the ones normally used to transmit data to devices
438d6c2c
DB
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
1da177e4 57 * transmit an arbitrary number of messages without interruption.
0c43ea54 58 * @count must be be less than 64k since msg.len is u16.
1da177e4 59 */
3ae70dee
JD
60extern int i2c_master_send(struct i2c_client *client, const char *buf,
61 int count);
62extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
1da177e4
LT
63
64/* Transfer num messages.
65 */
3ae70dee
JD
66extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
67 int num);
1da177e4
LT
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,
438d6c2c 71 and probably just as fast.
1da177e4
LT
72 Note that we use i2c_adapter here, because you do not need a specific
73 smbus adapter to call this function. */
3ae70dee
JD
74extern 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);
1da177e4
LT
77
78/* Now follow the 'nice' access routines. These also document the calling
ae7193f7 79 conventions of i2c_smbus_xfer. */
1da177e4 80
3ae70dee
JD
81extern s32 i2c_smbus_read_byte(struct i2c_client *client);
82extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value);
83extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);
84extern s32 i2c_smbus_write_byte_data(struct i2c_client *client,
85 u8 command, u8 value);
86extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
87extern s32 i2c_smbus_write_word_data(struct i2c_client *client,
88 u8 command, u16 value);
b86a1bc8
JD
89/* Returns the number of read bytes */
90extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
91 u8 command, u8 *values);
3ae70dee
JD
92extern s32 i2c_smbus_write_block_data(struct i2c_client *client,
93 u8 command, u8 length, const u8 *values);
31ec5bc5 94/* Returns the number of read bytes */
3ae70dee 95extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client,
4b2643d7 96 u8 command, u8 length, u8 *values);
3ae70dee 97extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client,
21bbd691 98 u8 command, u8 length,
46f5ed75 99 const u8 *values);
23af8400 100#endif /* I2C */
1da177e4 101
4735c98f
JD
102/**
103 * struct i2c_driver - represent an I2C device driver
104 * @class: What kind of i2c device we instantiate (for detect)
96e21e4f
JD
105 * @attach_adapter: Callback for bus addition (for legacy drivers)
106 * @detach_adapter: Callback for bus removal (for legacy drivers)
729d6dd5
JD
107 * @probe: Callback for device binding
108 * @remove: Callback for device unbinding
96e21e4f
JD
109 * @shutdown: Callback for device shutdown
110 * @suspend: Callback for device suspend
111 * @resume: Callback for device resume
72d2e9f9 112 * @alert: Alert callback, for example for the SMBus alert protocol
96e21e4f
JD
113 * @command: Callback for bus-wide signaling (optional)
114 * @driver: Device driver model driver
115 * @id_table: List of I2C devices supported by this driver
4735c98f 116 * @detect: Callback for device detection
c3813d6a 117 * @address_list: The I2C addresses to probe (for detect)
4735c98f 118 * @clients: List of detected clients we created (for i2c-core use only)
35d8b2e6
LR
119 *
120 * The driver.owner field should be set to the module owner of this driver.
121 * The driver.name field should be set to the name of this driver.
4735c98f
JD
122 *
123 * For automatic device detection, both @detect and @address_data must
124 * be defined. @class should also be set, otherwise only devices forced
125 * with module parameters will be created. The detect function must
126 * fill at least the name field of the i2c_board_info structure it is
127 * handed upon successful detection, and possibly also the flags field.
128 *
129 * If @detect is missing, the driver will still work fine for enumerated
130 * devices. Detected devices simply won't be supported. This is expected
131 * for the many I2C/SMBus devices which can't be detected reliably, and
132 * the ones which can always be enumerated in practice.
133 *
134 * The i2c_client structure which is handed to the @detect callback is
135 * not a real i2c_client. It is initialized just enough so that you can
136 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
137 * else with it. In particular, calling dev_dbg and friends on it is
138 * not allowed.
1da177e4 139 */
1da177e4 140struct i2c_driver {
1da177e4 141 unsigned int class;
1da177e4 142
729d6dd5
JD
143 /* Notifies the driver that a new bus has appeared or is about to be
144 * removed. You should avoid using this if you can, it will probably
145 * be removed in a near future.
1da177e4
LT
146 */
147 int (*attach_adapter)(struct i2c_adapter *);
148 int (*detach_adapter)(struct i2c_adapter *);
149
729d6dd5 150 /* Standard driver model interfaces */
d2653e92 151 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
a1d9e6e4 152 int (*remove)(struct i2c_client *);
7b4fbc50 153
f37dd80a
DB
154 /* driver model interfaces that don't relate to enumeration */
155 void (*shutdown)(struct i2c_client *);
156 int (*suspend)(struct i2c_client *, pm_message_t mesg);
157 int (*resume)(struct i2c_client *);
158
b5527a77
JD
159 /* Alert callback, for example for the SMBus alert protocol.
160 * The format and meaning of the data value depends on the protocol.
161 * For the SMBus alert protocol, there is a single bit of data passed
162 * as the alert response's low bit ("event flag").
163 */
164 void (*alert)(struct i2c_client *, unsigned int data);
165
1da177e4
LT
166 /* a ioctl like command that can be used to perform specific functions
167 * with the device.
168 */
3ae70dee 169 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
1da177e4
LT
170
171 struct device_driver driver;
d2653e92 172 const struct i2c_device_id *id_table;
4735c98f
JD
173
174 /* Device detection callback for automatic device creation */
310ec792 175 int (*detect)(struct i2c_client *, struct i2c_board_info *);
c3813d6a 176 const unsigned short *address_list;
4735c98f 177 struct list_head clients;
1da177e4
LT
178};
179#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
180
2096b956
DB
181/**
182 * struct i2c_client - represent an I2C slave device
d64f73be
DB
183 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
184 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
2096b956
DB
185 * @addr: Address used on the I2C bus connected to the parent adapter.
186 * @name: Indicates the type of the device, usually a chip name that's
187 * generic enough to hide second-sourcing and compatible revisions.
d64f73be 188 * @adapter: manages the bus segment hosting this I2C device
aa3481d5 189 * @driver: device's driver, hence pointer to access routines
2096b956 190 * @dev: Driver model device node for the slave.
d64f73be 191 * @irq: indicates the IRQ generated by this device (if any)
99cd8e25
JD
192 * @detected: member of an i2c_driver.clients list or i2c-core's
193 * userspace_devices list
2096b956
DB
194 *
195 * An i2c_client identifies a single device (i.e. chip) connected to an
d64f73be
DB
196 * i2c bus. The behaviour exposed to Linux is defined by the driver
197 * managing the device.
1da177e4
LT
198 */
199struct i2c_client {
2096b956 200 unsigned short flags; /* div., see below */
438d6c2c 201 unsigned short addr; /* chip address - NOTE: 7bit */
1da177e4 202 /* addresses are stored in the */
5071860a 203 /* _LOWER_ 7 bits */
2096b956 204 char name[I2C_NAME_SIZE];
1da177e4
LT
205 struct i2c_adapter *adapter; /* the adapter we sit on */
206 struct i2c_driver *driver; /* and our access routines */
1da177e4 207 struct device dev; /* the device structure */
8e29da9e 208 int irq; /* irq issued by device */
4735c98f 209 struct list_head detected;
1da177e4
LT
210};
211#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
212
9b766b81
DB
213extern struct i2c_client *i2c_verify_client(struct device *dev);
214
a61fc683
BG
215static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
216{
d75d53cd
MH
217 struct device * const dev = container_of(kobj, struct device, kobj);
218 return to_i2c_client(dev);
a61fc683
BG
219}
220
7d1d8999 221static inline void *i2c_get_clientdata(const struct i2c_client *dev)
1da177e4 222{
3ae70dee 223 return dev_get_drvdata(&dev->dev);
1da177e4
LT
224}
225
3ae70dee 226static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
1da177e4 227{
3ae70dee 228 dev_set_drvdata(&dev->dev, data);
1da177e4
LT
229}
230
9c1600ed
DB
231/**
232 * struct i2c_board_info - template for device creation
eb8a7908 233 * @type: chip type, to initialize i2c_client.name
9c1600ed
DB
234 * @flags: to initialize i2c_client.flags
235 * @addr: stored in i2c_client.addr
236 * @platform_data: stored in i2c_client.dev.platform_data
11f1f2af 237 * @archdata: copied into i2c_client.dev.archdata
72d2e9f9 238 * @of_node: pointer to OpenFirmware device node
9c1600ed 239 * @irq: stored in i2c_client.irq
d64f73be 240 *
9c1600ed
DB
241 * I2C doesn't actually support hardware probing, although controllers and
242 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
243 * a device at a given address. Drivers commonly need more information than
244 * that, such as chip type, configuration, associated IRQ, and so on.
245 *
246 * i2c_board_info is used to build tables of information listing I2C devices
729d6dd5
JD
247 * that are present. This information is used to grow the driver model tree.
248 * For mainboards this is done statically using i2c_register_board_info();
249 * bus numbers identify adapters that aren't yet available. For add-on boards,
250 * i2c_new_device() does this dynamically with the adapter already known.
9c1600ed
DB
251 */
252struct i2c_board_info {
9c1600ed
DB
253 char type[I2C_NAME_SIZE];
254 unsigned short flags;
255 unsigned short addr;
256 void *platform_data;
11f1f2af 257 struct dev_archdata *archdata;
d12d42f7
GL
258#ifdef CONFIG_OF
259 struct device_node *of_node;
260#endif
9c1600ed
DB
261 int irq;
262};
263
264/**
3760f736
JD
265 * I2C_BOARD_INFO - macro used to list an i2c device and its address
266 * @dev_type: identifies the device type
9c1600ed
DB
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
3760f736
JD
271 * fields (such as associated irq, or device-specific platform_data)
272 * are provided using conventional syntax.
9c1600ed 273 */
3ae70dee 274#define I2C_BOARD_INFO(dev_type, dev_addr) \
c758e8cf 275 .type = dev_type, .addr = (dev_addr)
9c1600ed
DB
276
277
23af8400 278#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
9c1600ed
DB
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 */
283extern struct i2c_client *
284i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
285
12b5053a
JD
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
9a94241a
JD
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.
12b5053a
JD
291 */
292extern struct i2c_client *
293i2c_new_probed_device(struct i2c_adapter *adap,
294 struct i2c_board_info *info,
9a94241a
JD
295 unsigned short const *addr_list,
296 int (*probe)(struct i2c_adapter *, unsigned short addr));
12b5053a 297
d44f19d5
JD
298/* Common custom probe functions */
299extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
300
e9f1373b
DB
301/* For devices that use several addresses, use i2c_new_dummy() to make
302 * client handles for the extra addresses.
303 */
304extern struct i2c_client *
60b129d7 305i2c_new_dummy(struct i2c_adapter *adap, u16 address);
e9f1373b 306
9c1600ed 307extern void i2c_unregister_device(struct i2c_client *);
23af8400 308#endif /* I2C */
9c1600ed
DB
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 */
26386763 314#ifdef CONFIG_I2C_BOARDINFO
9c1600ed 315extern int
3ae70dee
JD
316i2c_register_board_info(int busnum, struct i2c_board_info const *info,
317 unsigned n);
26386763
DB
318#else
319static inline int
3ae70dee
JD
320i2c_register_board_info(int busnum, struct i2c_board_info const *info,
321 unsigned n)
26386763
DB
322{
323 return 0;
324}
23af8400 325#endif /* I2C_BOARDINFO */
9c1600ed 326
1da177e4
LT
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 */
333struct i2c_algorithm {
1da177e4 334 /* If an adapter algorithm can't do I2C-level access, set master_xfer
438d6c2c 335 to NULL. If an adapter algorithm can do SMBus access, set
1da177e4
LT
336 smbus_xfer. If set to NULL, the SMBus protocol is simulated
337 using common I2C messages */
8ced8eee
JD
338 /* master_xfer should return the number of messages successfully
339 processed, or a negative value on error */
3ae70dee
JD
340 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
341 int num);
438d6c2c 342 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
3ae70dee
JD
343 unsigned short flags, char read_write,
344 u8 command, int size, union i2c_smbus_data *data);
1da177e4 345
1da177e4
LT
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 */
354struct i2c_adapter {
355 struct module *owner;
020789e9 356 unsigned int id;
14f55f7a 357 unsigned int class; /* classes to allow probing for */
af71ff69 358 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
1da177e4
LT
359 void *algo_data;
360
1da177e4 361 /* data fields that are valid for all devices */
194684e5 362 struct rt_mutex bus_lock;
1da177e4 363
cd97f39b 364 int timeout; /* in jiffies */
1da177e4
LT
365 int retries;
366 struct device dev; /* the adapter device */
1da177e4 367
1da177e4 368 int nr;
2096b956 369 char name[48];
1da177e4 370 struct completion dev_released;
6629dcff 371
dafc50d1 372 struct mutex userspace_clients_lock;
6629dcff 373 struct list_head userspace_clients;
1da177e4 374};
ef2c8321 375#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
1da177e4 376
7d1d8999 377static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
1da177e4 378{
3ae70dee 379 return dev_get_drvdata(&dev->dev);
1da177e4
LT
380}
381
3ae70dee 382static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
1da177e4 383{
3ae70dee 384 dev_set_drvdata(&dev->dev, data);
1da177e4
LT
385}
386
97cc4d49
JD
387static inline struct i2c_adapter *
388i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
0826374b 389{
97cc4d49
JD
390 struct device *parent = adapter->dev.parent;
391
392 if (parent != NULL && parent->type == &i2c_adapter_type)
393 return to_i2c_adapter(parent);
394 else
395 return NULL;
0826374b
ML
396}
397
fe61e07e
JD
398/* Adapter locking functions, exported for shared pin cases */
399void i2c_lock_adapter(struct i2c_adapter *);
400void i2c_unlock_adapter(struct i2c_adapter *);
afa08974 401
1da177e4 402/*flags for the client struct: */
3bbb835d
DB
403#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
404#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
405 /* Must equal I2C_M_TEN below */
406#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
1da177e4
LT
407
408/* i2c adapter classes (bitmask) */
409#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
c1b6b4f2 410#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
3401b2ff 411#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
1da177e4 412
1da177e4
LT
413/* Internal numbers to terminate lists */
414#define I2C_CLIENT_END 0xfffeU
1da177e4
LT
415
416/* The numbers to use to set I2C bus address */
417#define ANY_I2C_BUS 0xffff
1da177e4 418
c7036673
HV
419/* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
420#define I2C_ADDRS(addr, addrs...) \
421 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
422
1da177e4
LT
423
424/* ----- functions exported by i2c.o */
425
426/* administration...
427 */
23af8400 428#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1da177e4
LT
429extern int i2c_add_adapter(struct i2c_adapter *);
430extern int i2c_del_adapter(struct i2c_adapter *);
6e13e641 431extern int i2c_add_numbered_adapter(struct i2c_adapter *);
1da177e4 432
de59cf9e 433extern int i2c_register_driver(struct module *, struct i2c_driver *);
b3e82096 434extern void i2c_del_driver(struct i2c_driver *);
1da177e4 435
de59cf9e
GKH
436static inline int i2c_add_driver(struct i2c_driver *driver)
437{
438 return i2c_register_driver(THIS_MODULE, driver);
439}
440
e48d3319
JD
441extern struct i2c_client *i2c_use_client(struct i2c_client *client);
442extern void i2c_release_client(struct i2c_client *client);
1da177e4
LT
443
444/* call the i2c_client->command() of all attached clients with
445 * the given arguments */
446extern void i2c_clients_command(struct i2c_adapter *adap,
447 unsigned int cmd, void *arg);
448
3ae70dee 449extern struct i2c_adapter *i2c_get_adapter(int id);
1da177e4
LT
450extern void i2c_put_adapter(struct i2c_adapter *adap);
451
452
453/* Return the functionality mask */
454static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
455{
456 return adap->algo->functionality(adap);
457}
458
459/* Return 1 if adapter supports everything we need, 0 if not. */
460static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
461{
462 return (func & i2c_get_functionality(adap)) == func;
463}
464
3ae70dee 465/* Return the adapter number for a specific adapter */
cdcb1921
JD
466static inline int i2c_adapter_id(struct i2c_adapter *adap)
467{
468 return adap->nr;
469}
23af8400 470#endif /* I2C */
a1b9298e 471#endif /* __KERNEL__ */
cdcb1921 472
a64ec07d
DB
473/**
474 * struct i2c_msg - an I2C transaction segment beginning with START
475 * @addr: Slave address, either seven or ten bits. When this is a ten
476 * bit address, I2C_M_TEN must be set in @flags and the adapter
477 * must support I2C_FUNC_10BIT_ADDR.
478 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
479 * provided unless the adapter exported the relevant I2C_FUNC_*
480 * flags through i2c_check_functionality().
481 * @len: Number of data bytes in @buf being read from or written to the
482 * I2C slave address. For read transactions where I2C_M_RECV_LEN
483 * is set, the caller guarantees that this buffer can hold up to
484 * 32 bytes in addition to the initial length byte sent by the
485 * slave (plus, if used, the SMBus PEC); and this value will be
486 * incremented by the number of block data bytes received.
487 * @buf: The buffer into which data is read, or from which it's written.
488 *
489 * An i2c_msg is the low level representation of one segment of an I2C
490 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
491 * to userspace from i2c-dev, and to I2C adapter drivers through the
492 * @i2c_adapter.@master_xfer() method.
493 *
494 * Except when I2C "protocol mangling" is used, all I2C adapters implement
495 * the standard rules for I2C transactions. Each transaction begins with a
496 * START. That is followed by the slave address, and a bit encoding read
497 * versus write. Then follow all the data bytes, possibly including a byte
498 * with SMBus PEC. The transfer terminates with a NAK, or when all those
499 * bytes have been transferred and ACKed. If this is the last message in a
500 * group, it is followed by a STOP. Otherwise it is followed by the next
501 * @i2c_msg transaction segment, beginning with a (repeated) START.
502 *
503 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
504 * passing certain @flags may have changed those standard protocol behaviors.
505 * Those flags are only for use with broken/nonconforming slaves, and with
506 * adapters which are known to support the specific mangling options they
507 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
1da177e4
LT
508 */
509struct i2c_msg {
510 __u16 addr; /* slave address */
438d6c2c 511 __u16 flags;
a64ec07d
DB
512#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
513#define I2C_M_RD 0x0001 /* read data, from slave to master */
514#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
515#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
516#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
517#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
518#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
438d6c2c
DB
519 __u16 len; /* msg length */
520 __u8 *buf; /* pointer to msg data */
1da177e4
LT
521};
522
523/* To determine what functionality is present */
524
525#define I2C_FUNC_I2C 0x00000001
526#define I2C_FUNC_10BIT_ADDR 0x00000002
3ae70dee 527#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
6662cbb9 528#define I2C_FUNC_SMBUS_PEC 0x00000008
1da177e4 529#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
438d6c2c
DB
530#define I2C_FUNC_SMBUS_QUICK 0x00010000
531#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
532#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
533#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
534#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
535#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
536#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
537#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
538#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
539#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
1da177e4
LT
540#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
541#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
1da177e4 542
3ae70dee
JD
543#define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
544 I2C_FUNC_SMBUS_WRITE_BYTE)
545#define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
546 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
547#define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
548 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
549#define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
550 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
551#define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
552 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
553
554#define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
555 I2C_FUNC_SMBUS_BYTE | \
556 I2C_FUNC_SMBUS_BYTE_DATA | \
557 I2C_FUNC_SMBUS_WORD_DATA | \
558 I2C_FUNC_SMBUS_PROC_CALL | \
559 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
560 I2C_FUNC_SMBUS_I2C_BLOCK | \
561 I2C_FUNC_SMBUS_PEC)
1da177e4 562
438d6c2c
DB
563/*
564 * Data for SMBus Messages
1da177e4 565 */
438d6c2c 566#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
1da177e4
LT
567union i2c_smbus_data {
568 __u8 byte;
569 __u16 word;
332bf92b 570 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
3ae70dee 571 /* and one more for user-space compatibility */
1da177e4
LT
572};
573
ae7193f7 574/* i2c_smbus_xfer read or write markers */
1da177e4
LT
575#define I2C_SMBUS_READ 1
576#define I2C_SMBUS_WRITE 0
577
438d6c2c 578/* SMBus transaction types (size parameter in the above functions)
1da177e4
LT
579 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
580#define I2C_SMBUS_QUICK 0
581#define I2C_SMBUS_BYTE 1
438d6c2c 582#define I2C_SMBUS_BYTE_DATA 2
1da177e4
LT
583#define I2C_SMBUS_WORD_DATA 3
584#define I2C_SMBUS_PROC_CALL 4
585#define I2C_SMBUS_BLOCK_DATA 5
4b2643d7 586#define I2C_SMBUS_I2C_BLOCK_BROKEN 6
1da177e4 587#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
4b2643d7 588#define I2C_SMBUS_I2C_BLOCK_DATA 8
1da177e4 589
1da177e4 590#endif /* _LINUX_I2C_H */