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i2c: Clean up <linux/i2c.h>
[linux-2.6-block.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>
1da177e4 37
e9ca9eb9
JS		 38extern struct bus_type i2c_bus_type;
39
1da177e4
LT		 40/* --- General options ------------------------------------------------ */
41
42struct i2c_msg;
43struct i2c_algorithm;
44struct i2c_adapter;
45struct i2c_client;
46struct i2c_driver;
1da177e4 47union i2c_smbus_data;
4735c98f 48struct i2c_board_info;
1da177e4
LT		 49
50/*
51 * The master routines are the ones normally used to transmit data to devices
438d6c2c
DB		 52 * on a bus (or read from them). Apart from two basic transfer functions to
53 * transmit one message at a time, a more complex version can be used to
1da177e4
LT		 54 * transmit an arbitrary number of messages without interruption.
55 */
3ae70dee
JD		 56extern int i2c_master_send(struct i2c_client *client, const char *buf,
57 int count);
58extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
1da177e4
LT		 59
60/* Transfer num messages.
61 */
3ae70dee
JD		 62extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
63 int num);
1da177e4
LT		 64
65/* This is the very generalized SMBus access routine. You probably do not
66 want to use this, though; one of the functions below may be much easier,
438d6c2c 67 and probably just as fast.
1da177e4
LT		 68 Note that we use i2c_adapter here, because you do not need a specific
69 smbus adapter to call this function. */
3ae70dee
JD		 70extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
71 unsigned short flags, char read_write, u8 command,
72 int size, union i2c_smbus_data *data);
1da177e4
LT		 73
74/* Now follow the 'nice' access routines. These also document the calling
ae7193f7 75 conventions of i2c_smbus_xfer. */
1da177e4 76
3ae70dee
JD		 77extern s32 i2c_smbus_read_byte(struct i2c_client *client);
78extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value);
79extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);
80extern s32 i2c_smbus_write_byte_data(struct i2c_client *client,
81 u8 command, u8 value);
82extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
83extern s32 i2c_smbus_write_word_data(struct i2c_client *client,
84 u8 command, u16 value);
b86a1bc8
JD		 85/* Returns the number of read bytes */
86extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
87 u8 command, u8 *values);
3ae70dee
JD		 88extern s32 i2c_smbus_write_block_data(struct i2c_client *client,
89 u8 command, u8 length, const u8 *values);
31ec5bc5 90/* Returns the number of read bytes */
3ae70dee 91extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client,
4b2643d7 92 u8 command, u8 length, u8 *values);
3ae70dee 93extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client,
21bbd691 94 u8 command, u8 length,
46f5ed75 95 const u8 *values);
1da177e4 96
4735c98f
JD		 97/**
98 * struct i2c_driver - represent an I2C device driver
96e21e4f 99 * @id: Unique driver ID (optional)
4735c98f 100 * @class: What kind of i2c device we instantiate (for detect)
96e21e4f
JD		 101 * @attach_adapter: Callback for bus addition (for legacy drivers)
102 * @detach_adapter: Callback for bus removal (for legacy drivers)
103 * @detach_client: Callback for device removal (for legacy drivers)
104 * @probe: Callback for device binding (new-style drivers)
105 * @remove: Callback for device unbinding (new-style drivers)
106 * @shutdown: Callback for device shutdown
107 * @suspend: Callback for device suspend
108 * @resume: Callback for device resume
109 * @command: Callback for bus-wide signaling (optional)
110 * @driver: Device driver model driver
111 * @id_table: List of I2C devices supported by this driver
4735c98f
JD		 112 * @detect: Callback for device detection
113 * @address_data: The I2C addresses to probe, ignore or force (for detect)
114 * @clients: List of detected clients we created (for i2c-core use only)
35d8b2e6
LR		 115 *
116 * The driver.owner field should be set to the module owner of this driver.
117 * The driver.name field should be set to the name of this driver.
4735c98f
JD		 118 *
119 * For automatic device detection, both @detect and @address_data must
120 * be defined. @class should also be set, otherwise only devices forced
121 * with module parameters will be created. The detect function must
122 * fill at least the name field of the i2c_board_info structure it is
123 * handed upon successful detection, and possibly also the flags field.
124 *
125 * If @detect is missing, the driver will still work fine for enumerated
126 * devices. Detected devices simply won't be supported. This is expected
127 * for the many I2C/SMBus devices which can't be detected reliably, and
128 * the ones which can always be enumerated in practice.
129 *
130 * The i2c_client structure which is handed to the @detect callback is
131 * not a real i2c_client. It is initialized just enough so that you can
132 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
133 * else with it. In particular, calling dev_dbg and friends on it is
134 * not allowed.
1da177e4 135 */
1da177e4 136struct i2c_driver {
1da177e4
LT		 137 int id;
138 unsigned int class;
1da177e4
LT		 139
140 /* Notifies the driver that a new bus has appeared. This routine
141 * can be used by the driver to test if the bus meets its conditions
438d6c2c 142 * & seek for the presence of the chip(s) it supports. If found, it
1da177e4 143 * registers the client(s) that are on the bus to the i2c admin. via
7b4fbc50 144 * i2c_attach_client. (LEGACY I2C DRIVERS ONLY)
1da177e4
LT		 145 */
146 int (*attach_adapter)(struct i2c_adapter *);
147 int (*detach_adapter)(struct i2c_adapter *);
148
438d6c2c 149 /* tells the driver that a client is about to be deleted & gives it
1da177e4
LT		 150 * the chance to remove its private data. Also, if the client struct
151 * has been dynamically allocated by the driver in the function above,
7b4fbc50 152 * it must be freed here. (LEGACY I2C DRIVERS ONLY)
1da177e4
LT		 153 */
154 int (*detach_client)(struct i2c_client *);
f37dd80a 155
7b4fbc50
DB		 156 /* Standard driver model interfaces, for "new style" i2c drivers.
157 * With the driver model, device enumeration is NEVER done by drivers;
158 * it's done by infrastructure. (NEW STYLE DRIVERS ONLY)
159 */
d2653e92 160 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
a1d9e6e4 161 int (*remove)(struct i2c_client *);
7b4fbc50 162
f37dd80a
DB		 163 /* driver model interfaces that don't relate to enumeration */
164 void (*shutdown)(struct i2c_client *);
165 int (*suspend)(struct i2c_client *, pm_message_t mesg);
166 int (*resume)(struct i2c_client *);
167
1da177e4
LT		 168 /* a ioctl like command that can be used to perform specific functions
169 * with the device.
170 */
3ae70dee 171 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
1da177e4
LT		 172
173 struct device_driver driver;
d2653e92 174 const struct i2c_device_id *id_table;
4735c98f
JD		 175
176 /* Device detection callback for automatic device creation */
177 int (*detect)(struct i2c_client *, int kind, struct i2c_board_info *);
178 const struct i2c_client_address_data *address_data;
179 struct list_head clients;
1da177e4
LT		 180};
181#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
182
2096b956
DB		 183/**
184 * struct i2c_client - represent an I2C slave device
d64f73be
DB		 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
2096b956
DB		 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.
d64f73be 190 * @adapter: manages the bus segment hosting this I2C device
aa3481d5 191 * @driver: device's driver, hence pointer to access routines
2096b956 192 * @dev: Driver model device node for the slave.
d64f73be 193 * @irq: indicates the IRQ generated by this device (if any)
9b766b81 194 * @list: list of active/busy clients (DEPRECATED)
4735c98f 195 * @detected: member of an i2c_driver.clients list
aa3481d5 196 * @released: used to synchronize client releases & detaches and references
2096b956
DB		 197 *
198 * An i2c_client identifies a single device (i.e. chip) connected to an
d64f73be
DB		 199 * i2c bus. The behaviour exposed to Linux is defined by the driver
200 * managing the device.
1da177e4
LT		 201 */
202struct i2c_client {
2096b956 203 unsigned short flags; /* div., see below */
438d6c2c 204 unsigned short addr; /* chip address - NOTE: 7bit */
1da177e4 205 /* addresses are stored in the */
5071860a 206 /* _LOWER_ 7 bits */
2096b956 207 char name[I2C_NAME_SIZE];
1da177e4
LT		 208 struct i2c_adapter *adapter; /* the adapter we sit on */
209 struct i2c_driver *driver; /* and our access routines */
1da177e4 210 struct device dev; /* the device structure */
8e29da9e 211 int irq; /* irq issued by device */
9b766b81 212 struct list_head list; /* DEPRECATED */
4735c98f 213 struct list_head detected;
1da177e4
LT		 214 struct completion released;
215};
216#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
217
9b766b81
DB		 218extern struct i2c_client *i2c_verify_client(struct device *dev);
219
a61fc683 220static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
221{
d75d53cd
MH		 222 struct device * const dev = container_of(kobj, struct device, kobj);
223 return to_i2c_client(dev);
a61fc683 224}
225
7d1d8999 226static inline void *i2c_get_clientdata(const struct i2c_client *dev)
1da177e4 227{
3ae70dee 228 return dev_get_drvdata(&dev->dev);
1da177e4
LT		 229}
230
3ae70dee 231static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
1da177e4 232{
3ae70dee 233 dev_set_drvdata(&dev->dev, data);
1da177e4
LT		 234}
235
9c1600ed
DB		 236/**
237 * struct i2c_board_info - template for device creation
eb8a7908 238 * @type: chip type, to initialize i2c_client.name
9c1600ed
DB		 239 * @flags: to initialize i2c_client.flags
240 * @addr: stored in i2c_client.addr
241 * @platform_data: stored in i2c_client.dev.platform_data
242 * @irq: stored in i2c_client.irq
d64f73be 243 *
9c1600ed
DB		 244 * I2C doesn't actually support hardware probing, although controllers and
245 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
246 * a device at a given address. Drivers commonly need more information than
247 * that, such as chip type, configuration, associated IRQ, and so on.
248 *
249 * i2c_board_info is used to build tables of information listing I2C devices
250 * that are present. This information is used to grow the driver model tree
251 * for "new style" I2C drivers. For mainboards this is done statically using
d64f73be 252 * i2c_register_board_info(); bus numbers identify adapters that aren't
9c1600ed
DB		 253 * yet available. For add-on boards, i2c_new_device() does this dynamically
254 * with the adapter already known.
255 */
256struct i2c_board_info {
9c1600ed
DB		 257 char type[I2C_NAME_SIZE];
258 unsigned short flags;
259 unsigned short addr;
260 void *platform_data;
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) \
3760f736 275 .type = (dev_type), .addr = (dev_addr)
9c1600ed
DB		 276
277
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.
281 */
282extern struct i2c_client *
283i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
284
12b5053a
JD		 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.
288 */
289extern struct i2c_client *
290i2c_new_probed_device(struct i2c_adapter *adap,
291 struct i2c_board_info *info,
292 unsigned short const *addr_list);
293
e9f1373b
DB		 294/* For devices that use several addresses, use i2c_new_dummy() to make
295 * client handles for the extra addresses.
296 */
297extern struct i2c_client *
60b129d7 298i2c_new_dummy(struct i2c_adapter *adap, u16 address);
e9f1373b 299
9c1600ed
DB		 300extern void i2c_unregister_device(struct i2c_client *);
301
302/* Mainboard arch_initcall() code should register all its I2C devices.
303 * This is done at arch_initcall time, before declaring any i2c adapters.
304 * Modules for add-on boards must use other calls.
305 */
26386763 306#ifdef CONFIG_I2C_BOARDINFO
9c1600ed 307extern int
3ae70dee
JD		 308i2c_register_board_info(int busnum, struct i2c_board_info const *info,
309 unsigned n);
26386763
DB		 310#else
311static inline int
3ae70dee
JD		 312i2c_register_board_info(int busnum, struct i2c_board_info const *info,
313 unsigned n)
26386763
DB		 314{
315 return 0;
316}
317#endif
9c1600ed 318
1da177e4
LT		 319/*
320 * The following structs are for those who like to implement new bus drivers:
321 * i2c_algorithm is the interface to a class of hardware solutions which can
322 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
323 * to name two of the most common.
324 */
325struct i2c_algorithm {
1da177e4 326 /* If an adapter algorithm can't do I2C-level access, set master_xfer
438d6c2c 327 to NULL. If an adapter algorithm can do SMBus access, set
1da177e4
LT		 328 smbus_xfer. If set to NULL, the SMBus protocol is simulated
329 using common I2C messages */
8ced8eee
JD		 330 /* master_xfer should return the number of messages successfully
331 processed, or a negative value on error */
3ae70dee
JD		 332 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
333 int num);
438d6c2c 334 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
3ae70dee
JD		 335 unsigned short flags, char read_write,
336 u8 command, int size, union i2c_smbus_data *data);
1da177e4 337
1da177e4
LT		 338 /* To determine what the adapter supports */
339 u32 (*functionality) (struct i2c_adapter *);
340};
341
342/*
343 * i2c_adapter is the structure used to identify a physical i2c bus along
344 * with the access algorithms necessary to access it.
345 */
346struct i2c_adapter {
347 struct module *owner;
020789e9 348 unsigned int id;
14f55f7a 349 unsigned int class; /* classes to allow probing for */
af71ff69 350 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
1da177e4
LT		 351 void *algo_data;
352
353 /* --- administration stuff. */
354 int (*client_register)(struct i2c_client *);
355 int (*client_unregister)(struct i2c_client *);
356
357 /* data fields that are valid for all devices */
6ea23039 358 u8 level; /* nesting level for lockdep */
5c085d36
IM		 359 struct mutex bus_lock;
360 struct mutex clist_lock;
1da177e4
LT		 361
362 int timeout;
363 int retries;
364 struct device dev; /* the adapter device */
1da177e4 365
1da177e4 366 int nr;
9b766b81 367 struct list_head clients; /* DEPRECATED */
2096b956 368 char name[48];
1da177e4 369 struct completion dev_released;
1da177e4 370};
ef2c8321 371#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
1da177e4 372
7d1d8999 373static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
1da177e4 374{
3ae70dee 375 return dev_get_drvdata(&dev->dev);
1da177e4
LT		 376}
377
3ae70dee 378static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
1da177e4 379{
3ae70dee 380 dev_set_drvdata(&dev->dev, data);
1da177e4
LT		 381}
382
1da177e4 383/*flags for the client struct: */
3bbb835d
DB		 384#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
385#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
386 /* Must equal I2C_M_TEN below */
387#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
1da177e4
LT		 388
389/* i2c adapter classes (bitmask) */
390#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
391#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
392#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
c1b6b4f2 393#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
1da177e4
LT		 394#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */
395#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */
396#define I2C_CLASS_SOUND (1<<6) /* sound devices */
3401b2ff 397#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
1da177e4
LT		 398#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */
399
400/* i2c_client_address_data is the struct for holding default client
401 * addresses for a driver and for the parameters supplied on the
402 * command line
403 */
404struct i2c_client_address_data {
bfb6df24
MH		 405 const unsigned short *normal_i2c;
406 const unsigned short *probe;
407 const unsigned short *ignore;
408 const unsigned short * const *forces;
1da177e4
LT		 409};
410
411/* Internal numbers to terminate lists */
412#define I2C_CLIENT_END 0xfffeU
1da177e4
LT		 413
414/* The numbers to use to set I2C bus address */
415#define ANY_I2C_BUS 0xffff
1da177e4
LT		 416
417
418/* ----- functions exported by i2c.o */
419
420/* administration...
421 */
422extern int i2c_add_adapter(struct i2c_adapter *);
423extern int i2c_del_adapter(struct i2c_adapter *);
6e13e641 424extern int i2c_add_numbered_adapter(struct i2c_adapter *);
1da177e4 425
de59cf9e 426extern int i2c_register_driver(struct module *, struct i2c_driver *);
b3e82096 427extern void i2c_del_driver(struct i2c_driver *);
1da177e4 428
de59cf9e
GKH		 429static inline int i2c_add_driver(struct i2c_driver *driver)
430{
431 return i2c_register_driver(THIS_MODULE, driver);
432}
433
1da177e4
LT		 434extern int i2c_attach_client(struct i2c_client *);
435extern int i2c_detach_client(struct i2c_client *);
436
e48d3319
JD		 437extern struct i2c_client *i2c_use_client(struct i2c_client *client);
438extern void i2c_release_client(struct i2c_client *client);
1da177e4
LT		 439
440/* call the i2c_client->command() of all attached clients with
441 * the given arguments */
442extern void i2c_clients_command(struct i2c_adapter *adap,
443 unsigned int cmd, void *arg);
444
1da177e4
LT		 445/* Detect function. It iterates over all possible addresses itself.
446 * It will only call found_proc if some client is connected at the
447 * specific address (unless a 'force' matched);
448 */
438d6c2c 449extern int i2c_probe(struct i2c_adapter *adapter,
bfb6df24 450 const struct i2c_client_address_data *address_data,
1da177e4
LT		 451 int (*found_proc) (struct i2c_adapter *, int, int));
452
3ae70dee 453extern struct i2c_adapter *i2c_get_adapter(int id);
1da177e4
LT		 454extern void i2c_put_adapter(struct i2c_adapter *adap);
455
456
457/* Return the functionality mask */
458static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
459{
460 return adap->algo->functionality(adap);
461}
462
463/* Return 1 if adapter supports everything we need, 0 if not. */
464static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
465{
466 return (func & i2c_get_functionality(adap)) == func;
467}
468
3ae70dee 469/* Return the adapter number for a specific adapter */
cdcb1921
JD		 470static inline int i2c_adapter_id(struct i2c_adapter *adap)
471{
472 return adap->nr;
473}
a1b9298e 474#endif /* __KERNEL__ */
cdcb1921 475
a64ec07d
DB		 476/**
477 * struct i2c_msg - an I2C transaction segment beginning with START
478 * @addr: Slave address, either seven or ten bits. When this is a ten
479 * bit address, I2C_M_TEN must be set in @flags and the adapter
480 * must support I2C_FUNC_10BIT_ADDR.
481 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
482 * provided unless the adapter exported the relevant I2C_FUNC_*
483 * flags through i2c_check_functionality().
484 * @len: Number of data bytes in @buf being read from or written to the
485 * I2C slave address. For read transactions where I2C_M_RECV_LEN
486 * is set, the caller guarantees that this buffer can hold up to
487 * 32 bytes in addition to the initial length byte sent by the
488 * slave (plus, if used, the SMBus PEC); and this value will be
489 * incremented by the number of block data bytes received.
490 * @buf: The buffer into which data is read, or from which it's written.
491 *
492 * An i2c_msg is the low level representation of one segment of an I2C
493 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
494 * to userspace from i2c-dev, and to I2C adapter drivers through the
495 * @i2c_adapter.@master_xfer() method.
496 *
497 * Except when I2C "protocol mangling" is used, all I2C adapters implement
498 * the standard rules for I2C transactions. Each transaction begins with a
499 * START. That is followed by the slave address, and a bit encoding read
500 * versus write. Then follow all the data bytes, possibly including a byte
501 * with SMBus PEC. The transfer terminates with a NAK, or when all those
502 * bytes have been transferred and ACKed. If this is the last message in a
503 * group, it is followed by a STOP. Otherwise it is followed by the next
504 * @i2c_msg transaction segment, beginning with a (repeated) START.
505 *
506 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
507 * passing certain @flags may have changed those standard protocol behaviors.
508 * Those flags are only for use with broken/nonconforming slaves, and with
509 * adapters which are known to support the specific mangling options they
510 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
1da177e4
LT		 511 */
512struct i2c_msg {
513 __u16 addr; /* slave address */
438d6c2c 514 __u16 flags;
a64ec07d
DB		 515#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
516#define I2C_M_RD 0x0001 /* read data, from slave to master */
517#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
518#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
519#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
520#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
521#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
438d6c2c
DB		 522 __u16 len; /* msg length */
523 __u8 *buf; /* pointer to msg data */
1da177e4
LT		 524};
525
526/* To determine what functionality is present */
527
528#define I2C_FUNC_I2C 0x00000001
529#define I2C_FUNC_10BIT_ADDR 0x00000002
3ae70dee 530#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
6662cbb9 531#define I2C_FUNC_SMBUS_PEC 0x00000008
1da177e4 532#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
438d6c2c
DB		 533#define I2C_FUNC_SMBUS_QUICK 0x00010000
534#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
535#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
536#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
537#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
538#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
539#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
540#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
541#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
542#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
1da177e4
LT		 543#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
544#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
1da177e4 545
3ae70dee
JD		 546#define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
547 I2C_FUNC_SMBUS_WRITE_BYTE)
548#define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
549 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
550#define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
551 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
552#define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
553 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
554#define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
555 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
556
557#define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
558 I2C_FUNC_SMBUS_BYTE | \
559 I2C_FUNC_SMBUS_BYTE_DATA | \
560 I2C_FUNC_SMBUS_WORD_DATA | \
561 I2C_FUNC_SMBUS_PROC_CALL | \
562 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
563 I2C_FUNC_SMBUS_I2C_BLOCK | \
564 I2C_FUNC_SMBUS_PEC)
1da177e4 565
438d6c2c
DB		 566/*
567 * Data for SMBus Messages
1da177e4 568 */
438d6c2c 569#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
1da177e4
LT		 570union i2c_smbus_data {
571 __u8 byte;
572 __u16 word;
332bf92b 573 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
3ae70dee 574 /* and one more for user-space compatibility */
1da177e4
LT		 575};
576
ae7193f7 577/* i2c_smbus_xfer read or write markers */
1da177e4
LT		 578#define I2C_SMBUS_READ 1
579#define I2C_SMBUS_WRITE 0
580
438d6c2c 581/* SMBus transaction types (size parameter in the above functions)
1da177e4
LT		 582 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
583#define I2C_SMBUS_QUICK 0
584#define I2C_SMBUS_BYTE 1
438d6c2c 585#define I2C_SMBUS_BYTE_DATA 2
1da177e4
LT		 586#define I2C_SMBUS_WORD_DATA 3
587#define I2C_SMBUS_PROC_CALL 4
588#define I2C_SMBUS_BLOCK_DATA 5
4b2643d7 589#define I2C_SMBUS_I2C_BLOCK_BROKEN 6
1da177e4 590#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
4b2643d7 591#define I2C_SMBUS_I2C_BLOCK_DATA 8
1da177e4
LT		 592
593
a1b9298e 594#ifdef __KERNEL__
1da177e4 595
1da177e4
LT		 596/* These defines are used for probing i2c client addresses */
597/* The length of the option lists */
598#define I2C_CLIENT_MAX_OPTS 48
599
600/* Default fill of many variables */
601#define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
3ae70dee
JD		 602 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
603 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
604 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
605 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
606 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
607 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
608 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
609 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
610 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
611 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
612 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
613 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
614 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
615 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
616 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}
1da177e4
LT		 617
618/* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
619 module header */
620
621#define I2C_CLIENT_MODULE_PARM(var,desc) \
622 static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
623 static unsigned int var##_num; \
624 module_param_array(var, short, &var##_num, 0); \
3ae70dee 625 MODULE_PARM_DESC(var, desc)
1da177e4 626
f4b50261
JD		 627#define I2C_CLIENT_MODULE_PARM_FORCE(name) \
628I2C_CLIENT_MODULE_PARM(force_##name, \
629 "List of adapter,address pairs which are " \
630 "unquestionably assumed to contain a `" \
631 # name "' chip")
632
633
634#define I2C_CLIENT_INSMOD_COMMON \
635I2C_CLIENT_MODULE_PARM(probe, "List of adapter,address pairs to scan " \
636 "additionally"); \
637I2C_CLIENT_MODULE_PARM(ignore, "List of adapter,address pairs not to " \
638 "scan"); \
305183fc 639static const struct i2c_client_address_data addr_data = { \
f4b50261
JD		 640 .normal_i2c = normal_i2c, \
641 .probe = probe, \
642 .ignore = ignore, \
643 .forces = forces, \
644}
645
bfb6df24
MH		 646#define I2C_CLIENT_FORCE_TEXT \
647 "List of adapter,address pairs to boldly assume to be present"
648
f4b50261
JD		 649/* These are the ones you want to use in your own drivers. Pick the one
650 which matches the number of devices the driver differenciates between. */
bfb6df24
MH		 651#define I2C_CLIENT_INSMOD \
652I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
653static const unsigned short * const forces[] = { force, NULL }; \
f4b50261
JD		 654I2C_CLIENT_INSMOD_COMMON
655
656#define I2C_CLIENT_INSMOD_1(chip1) \
657enum chips { any_chip, chip1 }; \
bfb6df24 658I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261 659I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
bfb6df24
MH		 660static const unsigned short * const forces[] = { force, \
661 force_##chip1, NULL }; \
f4b50261
JD		 662I2C_CLIENT_INSMOD_COMMON
663
664#define I2C_CLIENT_INSMOD_2(chip1, chip2) \
665enum chips { any_chip, chip1, chip2 }; \
bfb6df24 666I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 667I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
668I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
bfb6df24
MH		 669static const unsigned short * const forces[] = { force, \
670 force_##chip1, force_##chip2, NULL }; \
f4b50261
JD		 671I2C_CLIENT_INSMOD_COMMON
672
673#define I2C_CLIENT_INSMOD_3(chip1, chip2, chip3) \
674enum chips { any_chip, chip1, chip2, chip3 }; \
bfb6df24 675I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 676I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
677I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
678I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
bfb6df24
MH		 679static const unsigned short * const forces[] = { force, \
680 force_##chip1, force_##chip2, force_##chip3, NULL }; \
f4b50261
JD		 681I2C_CLIENT_INSMOD_COMMON
682
683#define I2C_CLIENT_INSMOD_4(chip1, chip2, chip3, chip4) \
684enum chips { any_chip, chip1, chip2, chip3, chip4 }; \
bfb6df24 685I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 686I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
687I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
688I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
689I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
bfb6df24
MH		 690static const unsigned short * const forces[] = { force, \
691 force_##chip1, force_##chip2, force_##chip3, \
692 force_##chip4, NULL}; \
f4b50261
JD		 693I2C_CLIENT_INSMOD_COMMON
694
695#define I2C_CLIENT_INSMOD_5(chip1, chip2, chip3, chip4, chip5) \
696enum chips { any_chip, chip1, chip2, chip3, chip4, chip5 }; \
bfb6df24 697I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 698I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
699I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
700I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
701I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
702I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
bfb6df24
MH		 703static const unsigned short * const forces[] = { force, \
704 force_##chip1, force_##chip2, force_##chip3, \
705 force_##chip4, force_##chip5, NULL }; \
f4b50261
JD		 706I2C_CLIENT_INSMOD_COMMON
707
708#define I2C_CLIENT_INSMOD_6(chip1, chip2, chip3, chip4, chip5, chip6) \
709enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6 }; \
bfb6df24 710I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 711I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
712I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
713I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
714I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
715I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
716I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
bfb6df24
MH		 717static const unsigned short * const forces[] = { force, \
718 force_##chip1, force_##chip2, force_##chip3, \
719 force_##chip4, force_##chip5, force_##chip6, NULL }; \
f4b50261
JD		 720I2C_CLIENT_INSMOD_COMMON
721
722#define I2C_CLIENT_INSMOD_7(chip1, chip2, chip3, chip4, chip5, chip6, chip7) \
723enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
724 chip7 }; \
bfb6df24 725I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 726I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
727I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
728I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
729I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
730I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
731I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
732I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
bfb6df24
MH		 733static const unsigned short * const forces[] = { force, \
734 force_##chip1, force_##chip2, force_##chip3, \
735 force_##chip4, force_##chip5, force_##chip6, \
736 force_##chip7, NULL }; \
f4b50261
JD		 737I2C_CLIENT_INSMOD_COMMON
738
739#define I2C_CLIENT_INSMOD_8(chip1, chip2, chip3, chip4, chip5, chip6, chip7, chip8) \
740enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
741 chip7, chip8 }; \
bfb6df24 742I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \
f4b50261
JD		 743I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
744I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
745I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
746I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
747I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
748I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
749I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
750I2C_CLIENT_MODULE_PARM_FORCE(chip8); \
bfb6df24
MH		 751static const unsigned short * const forces[] = { force, \
752 force_##chip1, force_##chip2, force_##chip3, \
753 force_##chip4, force_##chip5, force_##chip6, \
754 force_##chip7, force_##chip8, NULL }; \
f4b50261 755I2C_CLIENT_INSMOD_COMMON
a1b9298e 756#endif /* __KERNEL__ */
1da177e4 757#endif /* _LINUX_I2C_H */
Linux 6.x block layer and io_uring tree(s)