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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 |
38 | extern struct bus_type i2c_bus_type; |
39 | ||
1da177e4 LT |
40 | /* --- General options ------------------------------------------------ */ |
41 | ||
42 | struct i2c_msg; | |
43 | struct i2c_algorithm; | |
44 | struct i2c_adapter; | |
45 | struct i2c_client; | |
46 | struct i2c_driver; | |
1da177e4 | 47 | union i2c_smbus_data; |
4735c98f | 48 | struct i2c_board_info; |
1da177e4 | 49 | |
23af8400 | 50 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 LT |
51 | /* |
52 | * The master routines are the ones normally used to transmit data to devices | |
438d6c2c DB |
53 | * on a bus (or read from them). Apart from two basic transfer functions to |
54 | * transmit one message at a time, a more complex version can be used to | |
1da177e4 | 55 | * transmit an arbitrary number of messages without interruption. |
0c43ea54 | 56 | * @count must be be less than 64k since msg.len is u16. |
1da177e4 | 57 | */ |
3ae70dee JD |
58 | extern int i2c_master_send(struct i2c_client *client, const char *buf, |
59 | int count); | |
60 | extern int i2c_master_recv(struct i2c_client *client, char *buf, int count); | |
1da177e4 LT |
61 | |
62 | /* Transfer num messages. | |
63 | */ | |
3ae70dee JD |
64 | extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, |
65 | int num); | |
1da177e4 LT |
66 | |
67 | /* This is the very generalized SMBus access routine. You probably do not | |
68 | want to use this, though; one of the functions below may be much easier, | |
438d6c2c | 69 | and probably just as fast. |
1da177e4 LT |
70 | Note that we use i2c_adapter here, because you do not need a specific |
71 | smbus adapter to call this function. */ | |
3ae70dee JD |
72 | extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, |
73 | unsigned short flags, char read_write, u8 command, | |
74 | int size, union i2c_smbus_data *data); | |
1da177e4 LT |
75 | |
76 | /* Now follow the 'nice' access routines. These also document the calling | |
ae7193f7 | 77 | conventions of i2c_smbus_xfer. */ |
1da177e4 | 78 | |
3ae70dee JD |
79 | extern s32 i2c_smbus_read_byte(struct i2c_client *client); |
80 | extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value); | |
81 | extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command); | |
82 | extern s32 i2c_smbus_write_byte_data(struct i2c_client *client, | |
83 | u8 command, u8 value); | |
84 | extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command); | |
85 | extern s32 i2c_smbus_write_word_data(struct i2c_client *client, | |
86 | u8 command, u16 value); | |
b86a1bc8 JD |
87 | /* Returns the number of read bytes */ |
88 | extern s32 i2c_smbus_read_block_data(struct i2c_client *client, | |
89 | u8 command, u8 *values); | |
3ae70dee JD |
90 | extern s32 i2c_smbus_write_block_data(struct i2c_client *client, |
91 | u8 command, u8 length, const u8 *values); | |
31ec5bc5 | 92 | /* Returns the number of read bytes */ |
3ae70dee | 93 | extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, |
4b2643d7 | 94 | u8 command, u8 length, u8 *values); |
3ae70dee | 95 | extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, |
21bbd691 | 96 | u8 command, u8 length, |
46f5ed75 | 97 | const u8 *values); |
23af8400 | 98 | #endif /* I2C */ |
1da177e4 | 99 | |
4735c98f JD |
100 | /** |
101 | * struct i2c_driver - represent an I2C device driver | |
102 | * @class: What kind of i2c device we instantiate (for detect) | |
96e21e4f JD |
103 | * @attach_adapter: Callback for bus addition (for legacy drivers) |
104 | * @detach_adapter: Callback for bus removal (for legacy drivers) | |
729d6dd5 JD |
105 | * @probe: Callback for device binding |
106 | * @remove: Callback for device unbinding | |
96e21e4f JD |
107 | * @shutdown: Callback for device shutdown |
108 | * @suspend: Callback for device suspend | |
109 | * @resume: Callback for device resume | |
110 | * @command: Callback for bus-wide signaling (optional) | |
111 | * @driver: Device driver model driver | |
112 | * @id_table: List of I2C devices supported by this driver | |
4735c98f | 113 | * @detect: Callback for device detection |
c3813d6a | 114 | * @address_list: The I2C addresses to probe (for detect) |
4735c98f | 115 | * @clients: List of detected clients we created (for i2c-core use only) |
35d8b2e6 LR |
116 | * |
117 | * The driver.owner field should be set to the module owner of this driver. | |
118 | * The driver.name field should be set to the name of this driver. | |
4735c98f JD |
119 | * |
120 | * For automatic device detection, both @detect and @address_data must | |
121 | * be defined. @class should also be set, otherwise only devices forced | |
122 | * with module parameters will be created. The detect function must | |
123 | * fill at least the name field of the i2c_board_info structure it is | |
124 | * handed upon successful detection, and possibly also the flags field. | |
125 | * | |
126 | * If @detect is missing, the driver will still work fine for enumerated | |
127 | * devices. Detected devices simply won't be supported. This is expected | |
128 | * for the many I2C/SMBus devices which can't be detected reliably, and | |
129 | * the ones which can always be enumerated in practice. | |
130 | * | |
131 | * The i2c_client structure which is handed to the @detect callback is | |
132 | * not a real i2c_client. It is initialized just enough so that you can | |
133 | * call i2c_smbus_read_byte_data and friends on it. Don't do anything | |
134 | * else with it. In particular, calling dev_dbg and friends on it is | |
135 | * not allowed. | |
1da177e4 | 136 | */ |
1da177e4 | 137 | struct i2c_driver { |
1da177e4 | 138 | unsigned int class; |
1da177e4 | 139 | |
729d6dd5 JD |
140 | /* Notifies the driver that a new bus has appeared or is about to be |
141 | * removed. You should avoid using this if you can, it will probably | |
142 | * be removed in a near future. | |
1da177e4 LT |
143 | */ |
144 | int (*attach_adapter)(struct i2c_adapter *); | |
145 | int (*detach_adapter)(struct i2c_adapter *); | |
146 | ||
729d6dd5 | 147 | /* Standard driver model interfaces */ |
d2653e92 | 148 | int (*probe)(struct i2c_client *, const struct i2c_device_id *); |
a1d9e6e4 | 149 | int (*remove)(struct i2c_client *); |
7b4fbc50 | 150 | |
f37dd80a DB |
151 | /* driver model interfaces that don't relate to enumeration */ |
152 | void (*shutdown)(struct i2c_client *); | |
153 | int (*suspend)(struct i2c_client *, pm_message_t mesg); | |
154 | int (*resume)(struct i2c_client *); | |
155 | ||
b5527a77 JD |
156 | /* Alert callback, for example for the SMBus alert protocol. |
157 | * The format and meaning of the data value depends on the protocol. | |
158 | * For the SMBus alert protocol, there is a single bit of data passed | |
159 | * as the alert response's low bit ("event flag"). | |
160 | */ | |
161 | void (*alert)(struct i2c_client *, unsigned int data); | |
162 | ||
1da177e4 LT |
163 | /* a ioctl like command that can be used to perform specific functions |
164 | * with the device. | |
165 | */ | |
3ae70dee | 166 | int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); |
1da177e4 LT |
167 | |
168 | struct device_driver driver; | |
d2653e92 | 169 | const struct i2c_device_id *id_table; |
4735c98f JD |
170 | |
171 | /* Device detection callback for automatic device creation */ | |
310ec792 | 172 | int (*detect)(struct i2c_client *, struct i2c_board_info *); |
c3813d6a | 173 | const unsigned short *address_list; |
4735c98f | 174 | struct list_head clients; |
1da177e4 LT |
175 | }; |
176 | #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) | |
177 | ||
2096b956 DB |
178 | /** |
179 | * struct i2c_client - represent an I2C slave device | |
d64f73be DB |
180 | * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address; |
181 | * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking | |
2096b956 DB |
182 | * @addr: Address used on the I2C bus connected to the parent adapter. |
183 | * @name: Indicates the type of the device, usually a chip name that's | |
184 | * generic enough to hide second-sourcing and compatible revisions. | |
d64f73be | 185 | * @adapter: manages the bus segment hosting this I2C device |
aa3481d5 | 186 | * @driver: device's driver, hence pointer to access routines |
2096b956 | 187 | * @dev: Driver model device node for the slave. |
d64f73be | 188 | * @irq: indicates the IRQ generated by this device (if any) |
99cd8e25 JD |
189 | * @detected: member of an i2c_driver.clients list or i2c-core's |
190 | * userspace_devices list | |
2096b956 DB |
191 | * |
192 | * An i2c_client identifies a single device (i.e. chip) connected to an | |
d64f73be DB |
193 | * i2c bus. The behaviour exposed to Linux is defined by the driver |
194 | * managing the device. | |
1da177e4 LT |
195 | */ |
196 | struct i2c_client { | |
2096b956 | 197 | unsigned short flags; /* div., see below */ |
438d6c2c | 198 | unsigned short addr; /* chip address - NOTE: 7bit */ |
1da177e4 | 199 | /* addresses are stored in the */ |
5071860a | 200 | /* _LOWER_ 7 bits */ |
2096b956 | 201 | char name[I2C_NAME_SIZE]; |
1da177e4 LT |
202 | struct i2c_adapter *adapter; /* the adapter we sit on */ |
203 | struct i2c_driver *driver; /* and our access routines */ | |
1da177e4 | 204 | struct device dev; /* the device structure */ |
8e29da9e | 205 | int irq; /* irq issued by device */ |
4735c98f | 206 | struct list_head detected; |
1da177e4 LT |
207 | }; |
208 | #define to_i2c_client(d) container_of(d, struct i2c_client, dev) | |
209 | ||
9b766b81 DB |
210 | extern struct i2c_client *i2c_verify_client(struct device *dev); |
211 | ||
a61fc683 | 212 | static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) |
213 | { | |
d75d53cd MH |
214 | struct device * const dev = container_of(kobj, struct device, kobj); |
215 | return to_i2c_client(dev); | |
a61fc683 | 216 | } |
217 | ||
7d1d8999 | 218 | static inline void *i2c_get_clientdata(const struct i2c_client *dev) |
1da177e4 | 219 | { |
3ae70dee | 220 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
221 | } |
222 | ||
3ae70dee | 223 | static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) |
1da177e4 | 224 | { |
3ae70dee | 225 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
226 | } |
227 | ||
9c1600ed DB |
228 | /** |
229 | * struct i2c_board_info - template for device creation | |
eb8a7908 | 230 | * @type: chip type, to initialize i2c_client.name |
9c1600ed DB |
231 | * @flags: to initialize i2c_client.flags |
232 | * @addr: stored in i2c_client.addr | |
233 | * @platform_data: stored in i2c_client.dev.platform_data | |
11f1f2af | 234 | * @archdata: copied into i2c_client.dev.archdata |
9c1600ed | 235 | * @irq: stored in i2c_client.irq |
d64f73be | 236 | * |
9c1600ed DB |
237 | * I2C doesn't actually support hardware probing, although controllers and |
238 | * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's | |
239 | * a device at a given address. Drivers commonly need more information than | |
240 | * that, such as chip type, configuration, associated IRQ, and so on. | |
241 | * | |
242 | * i2c_board_info is used to build tables of information listing I2C devices | |
729d6dd5 JD |
243 | * that are present. This information is used to grow the driver model tree. |
244 | * For mainboards this is done statically using i2c_register_board_info(); | |
245 | * bus numbers identify adapters that aren't yet available. For add-on boards, | |
246 | * i2c_new_device() does this dynamically with the adapter already known. | |
9c1600ed DB |
247 | */ |
248 | struct i2c_board_info { | |
9c1600ed DB |
249 | char type[I2C_NAME_SIZE]; |
250 | unsigned short flags; | |
251 | unsigned short addr; | |
252 | void *platform_data; | |
11f1f2af | 253 | struct dev_archdata *archdata; |
9c1600ed DB |
254 | int irq; |
255 | }; | |
256 | ||
257 | /** | |
3760f736 JD |
258 | * I2C_BOARD_INFO - macro used to list an i2c device and its address |
259 | * @dev_type: identifies the device type | |
9c1600ed DB |
260 | * @dev_addr: the device's address on the bus. |
261 | * | |
262 | * This macro initializes essential fields of a struct i2c_board_info, | |
263 | * declaring what has been provided on a particular board. Optional | |
3760f736 JD |
264 | * fields (such as associated irq, or device-specific platform_data) |
265 | * are provided using conventional syntax. | |
9c1600ed | 266 | */ |
3ae70dee | 267 | #define I2C_BOARD_INFO(dev_type, dev_addr) \ |
c758e8cf | 268 | .type = dev_type, .addr = (dev_addr) |
9c1600ed DB |
269 | |
270 | ||
23af8400 | 271 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
9c1600ed DB |
272 | /* Add-on boards should register/unregister their devices; e.g. a board |
273 | * with integrated I2C, a config eeprom, sensors, and a codec that's | |
274 | * used in conjunction with the primary hardware. | |
275 | */ | |
276 | extern struct i2c_client * | |
277 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info); | |
278 | ||
12b5053a JD |
279 | /* If you don't know the exact address of an I2C device, use this variant |
280 | * instead, which can probe for device presence in a list of possible | |
281 | * addresses. | |
282 | */ | |
283 | extern struct i2c_client * | |
284 | i2c_new_probed_device(struct i2c_adapter *adap, | |
285 | struct i2c_board_info *info, | |
286 | unsigned short const *addr_list); | |
287 | ||
e9f1373b DB |
288 | /* For devices that use several addresses, use i2c_new_dummy() to make |
289 | * client handles for the extra addresses. | |
290 | */ | |
291 | extern struct i2c_client * | |
60b129d7 | 292 | i2c_new_dummy(struct i2c_adapter *adap, u16 address); |
e9f1373b | 293 | |
9c1600ed | 294 | extern void i2c_unregister_device(struct i2c_client *); |
23af8400 | 295 | #endif /* I2C */ |
9c1600ed DB |
296 | |
297 | /* Mainboard arch_initcall() code should register all its I2C devices. | |
298 | * This is done at arch_initcall time, before declaring any i2c adapters. | |
299 | * Modules for add-on boards must use other calls. | |
300 | */ | |
26386763 | 301 | #ifdef CONFIG_I2C_BOARDINFO |
9c1600ed | 302 | extern int |
3ae70dee JD |
303 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
304 | unsigned n); | |
26386763 DB |
305 | #else |
306 | static inline int | |
3ae70dee JD |
307 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
308 | unsigned n) | |
26386763 DB |
309 | { |
310 | return 0; | |
311 | } | |
23af8400 | 312 | #endif /* I2C_BOARDINFO */ |
9c1600ed | 313 | |
1da177e4 LT |
314 | /* |
315 | * The following structs are for those who like to implement new bus drivers: | |
316 | * i2c_algorithm is the interface to a class of hardware solutions which can | |
317 | * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 | |
318 | * to name two of the most common. | |
319 | */ | |
320 | struct i2c_algorithm { | |
1da177e4 | 321 | /* If an adapter algorithm can't do I2C-level access, set master_xfer |
438d6c2c | 322 | to NULL. If an adapter algorithm can do SMBus access, set |
1da177e4 LT |
323 | smbus_xfer. If set to NULL, the SMBus protocol is simulated |
324 | using common I2C messages */ | |
8ced8eee JD |
325 | /* master_xfer should return the number of messages successfully |
326 | processed, or a negative value on error */ | |
3ae70dee JD |
327 | int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, |
328 | int num); | |
438d6c2c | 329 | int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, |
3ae70dee JD |
330 | unsigned short flags, char read_write, |
331 | u8 command, int size, union i2c_smbus_data *data); | |
1da177e4 | 332 | |
1da177e4 LT |
333 | /* To determine what the adapter supports */ |
334 | u32 (*functionality) (struct i2c_adapter *); | |
335 | }; | |
336 | ||
337 | /* | |
338 | * i2c_adapter is the structure used to identify a physical i2c bus along | |
339 | * with the access algorithms necessary to access it. | |
340 | */ | |
341 | struct i2c_adapter { | |
342 | struct module *owner; | |
020789e9 | 343 | unsigned int id; |
14f55f7a | 344 | unsigned int class; /* classes to allow probing for */ |
af71ff69 | 345 | const struct i2c_algorithm *algo; /* the algorithm to access the bus */ |
1da177e4 LT |
346 | void *algo_data; |
347 | ||
1da177e4 | 348 | /* data fields that are valid for all devices */ |
194684e5 | 349 | struct rt_mutex bus_lock; |
1da177e4 | 350 | |
cd97f39b | 351 | int timeout; /* in jiffies */ |
1da177e4 LT |
352 | int retries; |
353 | struct device dev; /* the adapter device */ | |
1da177e4 | 354 | |
1da177e4 | 355 | int nr; |
2096b956 | 356 | char name[48]; |
1da177e4 | 357 | struct completion dev_released; |
1da177e4 | 358 | }; |
ef2c8321 | 359 | #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) |
1da177e4 | 360 | |
7d1d8999 | 361 | static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) |
1da177e4 | 362 | { |
3ae70dee | 363 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
364 | } |
365 | ||
3ae70dee | 366 | static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) |
1da177e4 | 367 | { |
3ae70dee | 368 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
369 | } |
370 | ||
afa08974 JD |
371 | /** |
372 | * i2c_lock_adapter - Prevent access to an I2C bus segment | |
373 | * @adapter: Target I2C bus segment | |
374 | */ | |
375 | static inline void i2c_lock_adapter(struct i2c_adapter *adapter) | |
376 | { | |
194684e5 | 377 | rt_mutex_lock(&adapter->bus_lock); |
afa08974 JD |
378 | } |
379 | ||
380 | /** | |
381 | * i2c_unlock_adapter - Reauthorize access to an I2C bus segment | |
382 | * @adapter: Target I2C bus segment | |
383 | */ | |
384 | static inline void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
385 | { | |
194684e5 | 386 | rt_mutex_unlock(&adapter->bus_lock); |
afa08974 JD |
387 | } |
388 | ||
1da177e4 | 389 | /*flags for the client struct: */ |
3bbb835d DB |
390 | #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ |
391 | #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ | |
392 | /* Must equal I2C_M_TEN below */ | |
393 | #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ | |
1da177e4 LT |
394 | |
395 | /* i2c adapter classes (bitmask) */ | |
396 | #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ | |
397 | #define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */ | |
398 | #define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */ | |
c1b6b4f2 | 399 | #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ |
3401b2ff | 400 | #define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */ |
1da177e4 | 401 | |
1da177e4 LT |
402 | /* Internal numbers to terminate lists */ |
403 | #define I2C_CLIENT_END 0xfffeU | |
1da177e4 LT |
404 | |
405 | /* The numbers to use to set I2C bus address */ | |
406 | #define ANY_I2C_BUS 0xffff | |
1da177e4 | 407 | |
c7036673 HV |
408 | /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ |
409 | #define I2C_ADDRS(addr, addrs...) \ | |
410 | ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) | |
411 | ||
1da177e4 LT |
412 | |
413 | /* ----- functions exported by i2c.o */ | |
414 | ||
415 | /* administration... | |
416 | */ | |
23af8400 | 417 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 LT |
418 | extern int i2c_add_adapter(struct i2c_adapter *); |
419 | extern int i2c_del_adapter(struct i2c_adapter *); | |
6e13e641 | 420 | extern int i2c_add_numbered_adapter(struct i2c_adapter *); |
1da177e4 | 421 | |
de59cf9e | 422 | extern int i2c_register_driver(struct module *, struct i2c_driver *); |
b3e82096 | 423 | extern void i2c_del_driver(struct i2c_driver *); |
1da177e4 | 424 | |
de59cf9e GKH |
425 | static inline int i2c_add_driver(struct i2c_driver *driver) |
426 | { | |
427 | return i2c_register_driver(THIS_MODULE, driver); | |
428 | } | |
429 | ||
e48d3319 JD |
430 | extern struct i2c_client *i2c_use_client(struct i2c_client *client); |
431 | extern void i2c_release_client(struct i2c_client *client); | |
1da177e4 LT |
432 | |
433 | /* call the i2c_client->command() of all attached clients with | |
434 | * the given arguments */ | |
435 | extern void i2c_clients_command(struct i2c_adapter *adap, | |
436 | unsigned int cmd, void *arg); | |
437 | ||
3ae70dee | 438 | extern struct i2c_adapter *i2c_get_adapter(int id); |
1da177e4 LT |
439 | extern void i2c_put_adapter(struct i2c_adapter *adap); |
440 | ||
441 | ||
442 | /* Return the functionality mask */ | |
443 | static inline u32 i2c_get_functionality(struct i2c_adapter *adap) | |
444 | { | |
445 | return adap->algo->functionality(adap); | |
446 | } | |
447 | ||
448 | /* Return 1 if adapter supports everything we need, 0 if not. */ | |
449 | static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) | |
450 | { | |
451 | return (func & i2c_get_functionality(adap)) == func; | |
452 | } | |
453 | ||
3ae70dee | 454 | /* Return the adapter number for a specific adapter */ |
cdcb1921 JD |
455 | static inline int i2c_adapter_id(struct i2c_adapter *adap) |
456 | { | |
457 | return adap->nr; | |
458 | } | |
23af8400 | 459 | #endif /* I2C */ |
a1b9298e | 460 | #endif /* __KERNEL__ */ |
cdcb1921 | 461 | |
a64ec07d DB |
462 | /** |
463 | * struct i2c_msg - an I2C transaction segment beginning with START | |
464 | * @addr: Slave address, either seven or ten bits. When this is a ten | |
465 | * bit address, I2C_M_TEN must be set in @flags and the adapter | |
466 | * must support I2C_FUNC_10BIT_ADDR. | |
467 | * @flags: I2C_M_RD is handled by all adapters. No other flags may be | |
468 | * provided unless the adapter exported the relevant I2C_FUNC_* | |
469 | * flags through i2c_check_functionality(). | |
470 | * @len: Number of data bytes in @buf being read from or written to the | |
471 | * I2C slave address. For read transactions where I2C_M_RECV_LEN | |
472 | * is set, the caller guarantees that this buffer can hold up to | |
473 | * 32 bytes in addition to the initial length byte sent by the | |
474 | * slave (plus, if used, the SMBus PEC); and this value will be | |
475 | * incremented by the number of block data bytes received. | |
476 | * @buf: The buffer into which data is read, or from which it's written. | |
477 | * | |
478 | * An i2c_msg is the low level representation of one segment of an I2C | |
479 | * transaction. It is visible to drivers in the @i2c_transfer() procedure, | |
480 | * to userspace from i2c-dev, and to I2C adapter drivers through the | |
481 | * @i2c_adapter.@master_xfer() method. | |
482 | * | |
483 | * Except when I2C "protocol mangling" is used, all I2C adapters implement | |
484 | * the standard rules for I2C transactions. Each transaction begins with a | |
485 | * START. That is followed by the slave address, and a bit encoding read | |
486 | * versus write. Then follow all the data bytes, possibly including a byte | |
487 | * with SMBus PEC. The transfer terminates with a NAK, or when all those | |
488 | * bytes have been transferred and ACKed. If this is the last message in a | |
489 | * group, it is followed by a STOP. Otherwise it is followed by the next | |
490 | * @i2c_msg transaction segment, beginning with a (repeated) START. | |
491 | * | |
492 | * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then | |
493 | * passing certain @flags may have changed those standard protocol behaviors. | |
494 | * Those flags are only for use with broken/nonconforming slaves, and with | |
495 | * adapters which are known to support the specific mangling options they | |
496 | * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR). | |
1da177e4 LT |
497 | */ |
498 | struct i2c_msg { | |
499 | __u16 addr; /* slave address */ | |
438d6c2c | 500 | __u16 flags; |
a64ec07d DB |
501 | #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ |
502 | #define I2C_M_RD 0x0001 /* read data, from slave to master */ | |
503 | #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */ | |
504 | #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ | |
505 | #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ | |
506 | #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ | |
507 | #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ | |
438d6c2c DB |
508 | __u16 len; /* msg length */ |
509 | __u8 *buf; /* pointer to msg data */ | |
1da177e4 LT |
510 | }; |
511 | ||
512 | /* To determine what functionality is present */ | |
513 | ||
514 | #define I2C_FUNC_I2C 0x00000001 | |
515 | #define I2C_FUNC_10BIT_ADDR 0x00000002 | |
3ae70dee | 516 | #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */ |
6662cbb9 | 517 | #define I2C_FUNC_SMBUS_PEC 0x00000008 |
1da177e4 | 518 | #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */ |
438d6c2c DB |
519 | #define I2C_FUNC_SMBUS_QUICK 0x00010000 |
520 | #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000 | |
521 | #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000 | |
522 | #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000 | |
523 | #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000 | |
524 | #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000 | |
525 | #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000 | |
526 | #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000 | |
527 | #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000 | |
528 | #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 | |
1da177e4 LT |
529 | #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ |
530 | #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ | |
1da177e4 | 531 | |
3ae70dee JD |
532 | #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ |
533 | I2C_FUNC_SMBUS_WRITE_BYTE) | |
534 | #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \ | |
535 | I2C_FUNC_SMBUS_WRITE_BYTE_DATA) | |
536 | #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \ | |
537 | I2C_FUNC_SMBUS_WRITE_WORD_DATA) | |
538 | #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \ | |
539 | I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) | |
540 | #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \ | |
541 | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK) | |
542 | ||
543 | #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \ | |
544 | I2C_FUNC_SMBUS_BYTE | \ | |
545 | I2C_FUNC_SMBUS_BYTE_DATA | \ | |
546 | I2C_FUNC_SMBUS_WORD_DATA | \ | |
547 | I2C_FUNC_SMBUS_PROC_CALL | \ | |
548 | I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \ | |
549 | I2C_FUNC_SMBUS_I2C_BLOCK | \ | |
550 | I2C_FUNC_SMBUS_PEC) | |
1da177e4 | 551 | |
438d6c2c DB |
552 | /* |
553 | * Data for SMBus Messages | |
1da177e4 | 554 | */ |
438d6c2c | 555 | #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */ |
1da177e4 LT |
556 | union i2c_smbus_data { |
557 | __u8 byte; | |
558 | __u16 word; | |
332bf92b | 559 | __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */ |
3ae70dee | 560 | /* and one more for user-space compatibility */ |
1da177e4 LT |
561 | }; |
562 | ||
ae7193f7 | 563 | /* i2c_smbus_xfer read or write markers */ |
1da177e4 LT |
564 | #define I2C_SMBUS_READ 1 |
565 | #define I2C_SMBUS_WRITE 0 | |
566 | ||
438d6c2c | 567 | /* SMBus transaction types (size parameter in the above functions) |
1da177e4 LT |
568 | Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */ |
569 | #define I2C_SMBUS_QUICK 0 | |
570 | #define I2C_SMBUS_BYTE 1 | |
438d6c2c | 571 | #define I2C_SMBUS_BYTE_DATA 2 |
1da177e4 LT |
572 | #define I2C_SMBUS_WORD_DATA 3 |
573 | #define I2C_SMBUS_PROC_CALL 4 | |
574 | #define I2C_SMBUS_BLOCK_DATA 5 | |
4b2643d7 | 575 | #define I2C_SMBUS_I2C_BLOCK_BROKEN 6 |
1da177e4 | 576 | #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */ |
4b2643d7 | 577 | #define I2C_SMBUS_I2C_BLOCK_DATA 8 |
1da177e4 | 578 | |
1da177e4 | 579 | #endif /* _LINUX_I2C_H */ |