i2c.h 23 KB

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  1. /* ------------------------------------------------------------------------- */
  2. /* */
  3. /* i2c.h - definitions for the i2c-bus interface */
  4. /* */
  5. /* ------------------------------------------------------------------------- */
  6. /* Copyright (C) 1995-2000 Simon G. Vogl
  7. This program is free software; you can redistribute it and/or modify
  8. it under the terms of the GNU General Public License as published by
  9. the Free Software Foundation; either version 2 of the License, or
  10. (at your option) any later version.
  11. This program is distributed in the hope that it will be useful,
  12. but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. GNU General Public License for more details.
  15. You should have received a copy of the GNU General Public License
  16. along with this program; if not, write to the Free Software
  17. Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
  18. /* ------------------------------------------------------------------------- */
  19. /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
  20. Frodo Looijaard <frodol@dds.nl> */
  21. #ifndef _LINUX_I2C_H
  22. #define _LINUX_I2C_H
  23. #include <linux/types.h>
  24. #ifdef __KERNEL__
  25. #include <linux/module.h>
  26. #include <linux/mod_devicetable.h>
  27. #include <linux/device.h> /* for struct device */
  28. #include <linux/sched.h> /* for completion */
  29. #include <linux/mutex.h>
  30. #include <linux/of.h> /* for struct device_node */
  31. #include <linux/swab.h> /* for swab16 */
  32. extern struct bus_type i2c_bus_type;
  33. extern struct device_type i2c_adapter_type;
  34. /* --- General options ------------------------------------------------ */
  35. struct i2c_msg;
  36. struct i2c_algorithm;
  37. struct i2c_adapter;
  38. struct i2c_client;
  39. struct i2c_driver;
  40. union i2c_smbus_data;
  41. struct i2c_board_info;
  42. #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
  43. /*
  44. * The master routines are the ones normally used to transmit data to devices
  45. * on a bus (or read from them). Apart from two basic transfer functions to
  46. * transmit one message at a time, a more complex version can be used to
  47. * transmit an arbitrary number of messages without interruption.
  48. * @count must be be less than 64k since msg.len is u16.
  49. */
  50. extern int i2c_master_send(const struct i2c_client *client, const char *buf,
  51. int count);
  52. extern int i2c_master_recv(const struct i2c_client *client, char *buf,
  53. int count);
  54. /* Transfer num messages.
  55. */
  56. extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
  57. int num);
  58. /* This is the very generalized SMBus access routine. You probably do not
  59. want to use this, though; one of the functions below may be much easier,
  60. and probably just as fast.
  61. Note that we use i2c_adapter here, because you do not need a specific
  62. smbus adapter to call this function. */
  63. extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
  64. unsigned short flags, char read_write, u8 command,
  65. int size, union i2c_smbus_data *data);
  66. /* Now follow the 'nice' access routines. These also document the calling
  67. conventions of i2c_smbus_xfer. */
  68. extern s32 i2c_smbus_read_byte(const struct i2c_client *client);
  69. extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
  70. extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client,
  71. u8 command);
  72. extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client,
  73. u8 command, u8 value);
  74. extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
  75. u8 command);
  76. extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
  77. u8 command, u16 value);
  78. static inline s32
  79. i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command)
  80. {
  81. s32 value = i2c_smbus_read_word_data(client, command);
  82. return (value < 0) ? value : swab16(value);
  83. }
  84. static inline s32
  85. i2c_smbus_write_word_swapped(const struct i2c_client *client,
  86. u8 command, u16 value)
  87. {
  88. return i2c_smbus_write_word_data(client, command, swab16(value));
  89. }
  90. /* Returns the number of read bytes */
  91. extern s32 i2c_smbus_read_block_data(const struct i2c_client *client,
  92. u8 command, u8 *values);
  93. extern s32 i2c_smbus_write_block_data(const struct i2c_client *client,
  94. u8 command, u8 length, const u8 *values);
  95. /* Returns the number of read bytes */
  96. extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client,
  97. u8 command, u8 length, u8 *values);
  98. extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client,
  99. u8 command, u8 length,
  100. const u8 *values);
  101. #endif /* I2C */
  102. /**
  103. * struct i2c_driver - represent an I2C device driver
  104. * @class: What kind of i2c device we instantiate (for detect)
  105. * @attach_adapter: Callback for bus addition (deprecated)
  106. * @detach_adapter: Callback for bus removal (deprecated)
  107. * @probe: Callback for device binding
  108. * @remove: Callback for device unbinding
  109. * @shutdown: Callback for device shutdown
  110. * @suspend: Callback for device suspend
  111. * @resume: Callback for device resume
  112. * @alert: Alert callback, for example for the SMBus alert protocol
  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
  116. * @detect: Callback for device detection
  117. * @address_list: The I2C addresses to probe (for detect)
  118. * @clients: List of detected clients we created (for i2c-core use only)
  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.
  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.
  139. */
  140. struct i2c_driver {
  141. 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, it will be removed in a
  144. * near future.
  145. */
  146. int (*attach_adapter)(struct i2c_adapter *) __deprecated;
  147. int (*detach_adapter)(struct i2c_adapter *) __deprecated;
  148. /* Standard driver model interfaces */
  149. int (*probe)(struct i2c_client *, const struct i2c_device_id *);
  150. int (*remove)(struct i2c_client *);
  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. /* Alert callback, for example for the SMBus alert protocol.
  156. * The format and meaning of the data value depends on the protocol.
  157. * For the SMBus alert protocol, there is a single bit of data passed
  158. * as the alert response's low bit ("event flag").
  159. */
  160. void (*alert)(struct i2c_client *, unsigned int data);
  161. /* a ioctl like command that can be used to perform specific functions
  162. * with the device.
  163. */
  164. int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
  165. struct device_driver driver;
  166. const struct i2c_device_id *id_table;
  167. /* Device detection callback for automatic device creation */
  168. int (*detect)(struct i2c_client *, struct i2c_board_info *);
  169. const unsigned short *address_list;
  170. struct list_head clients;
  171. };
  172. #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
  173. /**
  174. * struct i2c_client - represent an I2C slave device
  175. * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
  176. * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
  177. * @addr: Address used on the I2C bus connected to the parent adapter.
  178. * @name: Indicates the type of the device, usually a chip name that's
  179. * generic enough to hide second-sourcing and compatible revisions.
  180. * @adapter: manages the bus segment hosting this I2C device
  181. * @driver: device's driver, hence pointer to access routines
  182. * @dev: Driver model device node for the slave.
  183. * @irq: indicates the IRQ generated by this device (if any)
  184. * @detected: member of an i2c_driver.clients list or i2c-core's
  185. * userspace_devices list
  186. *
  187. * An i2c_client identifies a single device (i.e. chip) connected to an
  188. * i2c bus. The behaviour exposed to Linux is defined by the driver
  189. * managing the device.
  190. */
  191. struct i2c_client {
  192. unsigned short flags; /* div., see below */
  193. unsigned short addr; /* chip address - NOTE: 7bit */
  194. /* addresses are stored in the */
  195. /* _LOWER_ 7 bits */
  196. char name[I2C_NAME_SIZE];
  197. struct i2c_adapter *adapter; /* the adapter we sit on */
  198. struct i2c_driver *driver; /* and our access routines */
  199. struct device dev; /* the device structure */
  200. int irq; /* irq issued by device */
  201. struct list_head detected;
  202. };
  203. #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
  204. extern struct i2c_client *i2c_verify_client(struct device *dev);
  205. static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
  206. {
  207. struct device * const dev = container_of(kobj, struct device, kobj);
  208. return to_i2c_client(dev);
  209. }
  210. static inline void *i2c_get_clientdata(const struct i2c_client *dev)
  211. {
  212. return dev_get_drvdata(&dev->dev);
  213. }
  214. static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
  215. {
  216. dev_set_drvdata(&dev->dev, data);
  217. }
  218. /**
  219. * struct i2c_board_info - template for device creation
  220. * @type: chip type, to initialize i2c_client.name
  221. * @flags: to initialize i2c_client.flags
  222. * @addr: stored in i2c_client.addr
  223. * @platform_data: stored in i2c_client.dev.platform_data
  224. * @archdata: copied into i2c_client.dev.archdata
  225. * @of_node: pointer to OpenFirmware device node
  226. * @irq: stored in i2c_client.irq
  227. *
  228. * I2C doesn't actually support hardware probing, although controllers and
  229. * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
  230. * a device at a given address. Drivers commonly need more information than
  231. * that, such as chip type, configuration, associated IRQ, and so on.
  232. *
  233. * i2c_board_info is used to build tables of information listing I2C devices
  234. * that are present. This information is used to grow the driver model tree.
  235. * For mainboards this is done statically using i2c_register_board_info();
  236. * bus numbers identify adapters that aren't yet available. For add-on boards,
  237. * i2c_new_device() does this dynamically with the adapter already known.
  238. */
  239. struct i2c_board_info {
  240. char type[I2C_NAME_SIZE];
  241. unsigned short flags;
  242. unsigned short addr;
  243. void *platform_data;
  244. struct dev_archdata *archdata;
  245. struct device_node *of_node;
  246. int irq;
  247. };
  248. /**
  249. * I2C_BOARD_INFO - macro used to list an i2c device and its address
  250. * @dev_type: identifies the device type
  251. * @dev_addr: the device's address on the bus.
  252. *
  253. * This macro initializes essential fields of a struct i2c_board_info,
  254. * declaring what has been provided on a particular board. Optional
  255. * fields (such as associated irq, or device-specific platform_data)
  256. * are provided using conventional syntax.
  257. */
  258. #define I2C_BOARD_INFO(dev_type, dev_addr) \
  259. .type = dev_type, .addr = (dev_addr)
  260. #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
  261. /* Add-on boards should register/unregister their devices; e.g. a board
  262. * with integrated I2C, a config eeprom, sensors, and a codec that's
  263. * used in conjunction with the primary hardware.
  264. */
  265. extern struct i2c_client *
  266. i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
  267. /* If you don't know the exact address of an I2C device, use this variant
  268. * instead, which can probe for device presence in a list of possible
  269. * addresses. The "probe" callback function is optional. If it is provided,
  270. * it must return 1 on successful probe, 0 otherwise. If it is not provided,
  271. * a default probing method is used.
  272. */
  273. extern struct i2c_client *
  274. i2c_new_probed_device(struct i2c_adapter *adap,
  275. struct i2c_board_info *info,
  276. unsigned short const *addr_list,
  277. int (*probe)(struct i2c_adapter *, unsigned short addr));
  278. /* Common custom probe functions */
  279. extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
  280. /* For devices that use several addresses, use i2c_new_dummy() to make
  281. * client handles for the extra addresses.
  282. */
  283. extern struct i2c_client *
  284. i2c_new_dummy(struct i2c_adapter *adap, u16 address);
  285. extern void i2c_unregister_device(struct i2c_client *);
  286. #endif /* I2C */
  287. /* Mainboard arch_initcall() code should register all its I2C devices.
  288. * This is done at arch_initcall time, before declaring any i2c adapters.
  289. * Modules for add-on boards must use other calls.
  290. */
  291. #ifdef CONFIG_I2C_BOARDINFO
  292. extern int
  293. i2c_register_board_info(int busnum, struct i2c_board_info const *info,
  294. unsigned n);
  295. #else
  296. static inline int
  297. i2c_register_board_info(int busnum, struct i2c_board_info const *info,
  298. unsigned n)
  299. {
  300. return 0;
  301. }
  302. #endif /* I2C_BOARDINFO */
  303. /*
  304. * The following structs are for those who like to implement new bus drivers:
  305. * i2c_algorithm is the interface to a class of hardware solutions which can
  306. * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
  307. * to name two of the most common.
  308. */
  309. struct i2c_algorithm {
  310. /* If an adapter algorithm can't do I2C-level access, set master_xfer
  311. to NULL. If an adapter algorithm can do SMBus access, set
  312. smbus_xfer. If set to NULL, the SMBus protocol is simulated
  313. using common I2C messages */
  314. /* master_xfer should return the number of messages successfully
  315. processed, or a negative value on error */
  316. int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
  317. int num);
  318. int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
  319. unsigned short flags, char read_write,
  320. u8 command, int size, union i2c_smbus_data *data);
  321. /* To determine what the adapter supports */
  322. u32 (*functionality) (struct i2c_adapter *);
  323. };
  324. /*
  325. * i2c_adapter is the structure used to identify a physical i2c bus along
  326. * with the access algorithms necessary to access it.
  327. */
  328. struct i2c_adapter {
  329. struct module *owner;
  330. unsigned int class; /* classes to allow probing for */
  331. const struct i2c_algorithm *algo; /* the algorithm to access the bus */
  332. void *algo_data;
  333. /* data fields that are valid for all devices */
  334. struct rt_mutex bus_lock;
  335. int timeout; /* in jiffies */
  336. int retries;
  337. struct device dev; /* the adapter device */
  338. int nr;
  339. char name[48];
  340. struct completion dev_released;
  341. struct mutex userspace_clients_lock;
  342. struct list_head userspace_clients;
  343. };
  344. #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
  345. static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
  346. {
  347. return dev_get_drvdata(&dev->dev);
  348. }
  349. static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
  350. {
  351. dev_set_drvdata(&dev->dev, data);
  352. }
  353. static inline struct i2c_adapter *
  354. i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
  355. {
  356. struct device *parent = adapter->dev.parent;
  357. if (parent != NULL && parent->type == &i2c_adapter_type)
  358. return to_i2c_adapter(parent);
  359. else
  360. return NULL;
  361. }
  362. int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
  363. /* Adapter locking functions, exported for shared pin cases */
  364. void i2c_lock_adapter(struct i2c_adapter *);
  365. void i2c_unlock_adapter(struct i2c_adapter *);
  366. /*flags for the client struct: */
  367. #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
  368. #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
  369. /* Must equal I2C_M_TEN below */
  370. #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
  371. /* i2c adapter classes (bitmask) */
  372. #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
  373. #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
  374. #define I2C_CLASS_SPD (1<<7) /* Memory modules */
  375. /* Internal numbers to terminate lists */
  376. #define I2C_CLIENT_END 0xfffeU
  377. /* The numbers to use to set I2C bus address */
  378. #define ANY_I2C_BUS 0xffff
  379. /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
  380. #define I2C_ADDRS(addr, addrs...) \
  381. ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
  382. /* ----- functions exported by i2c.o */
  383. /* administration...
  384. */
  385. #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
  386. extern int i2c_add_adapter(struct i2c_adapter *);
  387. extern int i2c_del_adapter(struct i2c_adapter *);
  388. extern int i2c_add_numbered_adapter(struct i2c_adapter *);
  389. extern int i2c_register_driver(struct module *, struct i2c_driver *);
  390. extern void i2c_del_driver(struct i2c_driver *);
  391. static inline int i2c_add_driver(struct i2c_driver *driver)
  392. {
  393. return i2c_register_driver(THIS_MODULE, driver);
  394. }
  395. extern struct i2c_client *i2c_use_client(struct i2c_client *client);
  396. extern void i2c_release_client(struct i2c_client *client);
  397. /* call the i2c_client->command() of all attached clients with
  398. * the given arguments */
  399. extern void i2c_clients_command(struct i2c_adapter *adap,
  400. unsigned int cmd, void *arg);
  401. extern struct i2c_adapter *i2c_get_adapter(int nr);
  402. extern void i2c_put_adapter(struct i2c_adapter *adap);
  403. /* Return the functionality mask */
  404. static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
  405. {
  406. return adap->algo->functionality(adap);
  407. }
  408. /* Return 1 if adapter supports everything we need, 0 if not. */
  409. static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
  410. {
  411. return (func & i2c_get_functionality(adap)) == func;
  412. }
  413. /* Return the adapter number for a specific adapter */
  414. static inline int i2c_adapter_id(struct i2c_adapter *adap)
  415. {
  416. return adap->nr;
  417. }
  418. #endif /* I2C */
  419. #endif /* __KERNEL__ */
  420. /**
  421. * struct i2c_msg - an I2C transaction segment beginning with START
  422. * @addr: Slave address, either seven or ten bits. When this is a ten
  423. * bit address, I2C_M_TEN must be set in @flags and the adapter
  424. * must support I2C_FUNC_10BIT_ADDR.
  425. * @flags: I2C_M_RD is handled by all adapters. No other flags may be
  426. * provided unless the adapter exported the relevant I2C_FUNC_*
  427. * flags through i2c_check_functionality().
  428. * @len: Number of data bytes in @buf being read from or written to the
  429. * I2C slave address. For read transactions where I2C_M_RECV_LEN
  430. * is set, the caller guarantees that this buffer can hold up to
  431. * 32 bytes in addition to the initial length byte sent by the
  432. * slave (plus, if used, the SMBus PEC); and this value will be
  433. * incremented by the number of block data bytes received.
  434. * @buf: The buffer into which data is read, or from which it's written.
  435. *
  436. * An i2c_msg is the low level representation of one segment of an I2C
  437. * transaction. It is visible to drivers in the @i2c_transfer() procedure,
  438. * to userspace from i2c-dev, and to I2C adapter drivers through the
  439. * @i2c_adapter.@master_xfer() method.
  440. *
  441. * Except when I2C "protocol mangling" is used, all I2C adapters implement
  442. * the standard rules for I2C transactions. Each transaction begins with a
  443. * START. That is followed by the slave address, and a bit encoding read
  444. * versus write. Then follow all the data bytes, possibly including a byte
  445. * with SMBus PEC. The transfer terminates with a NAK, or when all those
  446. * bytes have been transferred and ACKed. If this is the last message in a
  447. * group, it is followed by a STOP. Otherwise it is followed by the next
  448. * @i2c_msg transaction segment, beginning with a (repeated) START.
  449. *
  450. * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
  451. * passing certain @flags may have changed those standard protocol behaviors.
  452. * Those flags are only for use with broken/nonconforming slaves, and with
  453. * adapters which are known to support the specific mangling options they
  454. * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
  455. */
  456. struct i2c_msg {
  457. __u16 addr; /* slave address */
  458. __u16 flags;
  459. #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
  460. #define I2C_M_RD 0x0001 /* read data, from slave to master */
  461. #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
  462. #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
  463. #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
  464. #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
  465. #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
  466. __u16 len; /* msg length */
  467. __u8 *buf; /* pointer to msg data */
  468. };
  469. /* To determine what functionality is present */
  470. #define I2C_FUNC_I2C 0x00000001
  471. #define I2C_FUNC_10BIT_ADDR 0x00000002
  472. #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
  473. #define I2C_FUNC_SMBUS_PEC 0x00000008
  474. #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
  475. #define I2C_FUNC_SMBUS_QUICK 0x00010000
  476. #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
  477. #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
  478. #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
  479. #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
  480. #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
  481. #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
  482. #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
  483. #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
  484. #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
  485. #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
  486. #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
  487. #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
  488. I2C_FUNC_SMBUS_WRITE_BYTE)
  489. #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
  490. I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
  491. #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
  492. I2C_FUNC_SMBUS_WRITE_WORD_DATA)
  493. #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
  494. I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
  495. #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
  496. I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
  497. #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
  498. I2C_FUNC_SMBUS_BYTE | \
  499. I2C_FUNC_SMBUS_BYTE_DATA | \
  500. I2C_FUNC_SMBUS_WORD_DATA | \
  501. I2C_FUNC_SMBUS_PROC_CALL | \
  502. I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
  503. I2C_FUNC_SMBUS_I2C_BLOCK | \
  504. I2C_FUNC_SMBUS_PEC)
  505. /*
  506. * Data for SMBus Messages
  507. */
  508. #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
  509. union i2c_smbus_data {
  510. __u8 byte;
  511. __u16 word;
  512. __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
  513. /* and one more for user-space compatibility */
  514. };
  515. /* i2c_smbus_xfer read or write markers */
  516. #define I2C_SMBUS_READ 1
  517. #define I2C_SMBUS_WRITE 0
  518. /* SMBus transaction types (size parameter in the above functions)
  519. Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
  520. #define I2C_SMBUS_QUICK 0
  521. #define I2C_SMBUS_BYTE 1
  522. #define I2C_SMBUS_BYTE_DATA 2
  523. #define I2C_SMBUS_WORD_DATA 3
  524. #define I2C_SMBUS_PROC_CALL 4
  525. #define I2C_SMBUS_BLOCK_DATA 5
  526. #define I2C_SMBUS_I2C_BLOCK_BROKEN 6
  527. #define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
  528. #define I2C_SMBUS_I2C_BLOCK_DATA 8
  529. #endif /* _LINUX_I2C_H */