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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* ------------------------------------------------------------------------- */
David Brownell438d6c22006-12-10 21:21:31 +01002/* */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003/* i2c.h - definitions for the i2c-bus interface */
David Brownell438d6c22006-12-10 21:21:31 +01004/* */
Linus Torvalds1da177e2005-04-16 15:20:36 -07005/* ------------------------------------------------------------------------- */
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
David Woodhousea1b92982006-04-25 14:14:52 +010023/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
Linus Torvalds1da177e2005-04-16 15:20:36 -070024 Frodo Looijaard <frodol@dds.nl> */
25
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#ifndef _LINUX_I2C_H
27#define _LINUX_I2C_H
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/types.h>
David Brownell438d6c22006-12-10 21:21:31 +010030#ifdef __KERNEL__
David Woodhousea1b92982006-04-25 14:14:52 +010031#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/i2c-id.h>
Greg Kroah-Hartmana9d1b242005-10-22 00:23:27 +020033#include <linux/mod_devicetable.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/device.h> /* for struct device */
Tim Schmielau4e57b682005-10-30 15:03:48 -080035#include <linux/sched.h> /* for completion */
Ingo Molnar5c085d32006-01-18 23:16:04 +010036#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38/* --- General options ------------------------------------------------ */
39
40struct i2c_msg;
41struct i2c_algorithm;
42struct i2c_adapter;
43struct i2c_client;
44struct i2c_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -070045union i2c_smbus_data;
46
47/*
48 * The master routines are the ones normally used to transmit data to devices
David Brownell438d6c22006-12-10 21:21:31 +010049 * on a bus (or read from them). Apart from two basic transfer functions to
50 * transmit one message at a time, a more complex version can be used to
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 * transmit an arbitrary number of messages without interruption.
52 */
53extern int i2c_master_send(struct i2c_client *,const char* ,int);
54extern int i2c_master_recv(struct i2c_client *,char* ,int);
55
56/* Transfer num messages.
57 */
58extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
59
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61/* This is the very generalized SMBus access routine. You probably do not
62 want to use this, though; one of the functions below may be much easier,
David Brownell438d6c22006-12-10 21:21:31 +010063 and probably just as fast.
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 Note that we use i2c_adapter here, because you do not need a specific
65 smbus adapter to call this function. */
David Brownell438d6c22006-12-10 21:21:31 +010066extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 unsigned short flags,
68 char read_write, u8 command, int size,
69 union i2c_smbus_data * data);
70
71/* Now follow the 'nice' access routines. These also document the calling
72 conventions of smbus_access. */
73
74extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
75extern s32 i2c_smbus_read_byte(struct i2c_client * client);
76extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
77extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
78extern s32 i2c_smbus_write_byte_data(struct i2c_client * client,
79 u8 command, u8 value);
80extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
81extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
82 u8 command, u16 value);
Jean Delvareb86a1bc2007-05-01 23:26:34 +020083/* Returns the number of read bytes */
84extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
85 u8 command, u8 *values);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
87 u8 command, u8 length,
Krzysztof Halasa46f5ed72006-06-12 21:42:20 +020088 const u8 *values);
Jean Delvare31ec5bc2005-10-08 00:04:13 +020089/* Returns the number of read bytes */
Linus Torvalds1da177e2005-04-16 15:20:36 -070090extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
Jean Delvare4b2643d2007-07-12 14:12:29 +020091 u8 command, u8 length, u8 *values);
Jean Delvare21bbd692006-01-09 15:19:18 +110092extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
93 u8 command, u8 length,
Krzysztof Halasa46f5ed72006-06-12 21:42:20 +020094 const u8 *values);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96/*
97 * A driver is capable of handling one or more physical devices present on
98 * I2C adapters. This information is used to inform the driver of adapter
99 * events.
Laurent Riffard35d8b2e2005-11-26 20:34:05 +0100100 *
101 * The driver.owner field should be set to the module owner of this driver.
102 * The driver.name field should be set to the name of this driver.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 */
104
105struct i2c_driver {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 int id;
107 unsigned int class;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
109 /* Notifies the driver that a new bus has appeared. This routine
110 * can be used by the driver to test if the bus meets its conditions
David Brownell438d6c22006-12-10 21:21:31 +0100111 * & seek for the presence of the chip(s) it supports. If found, it
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 * registers the client(s) that are on the bus to the i2c admin. via
David Brownell7b4fbc52007-05-01 23:26:30 +0200113 * i2c_attach_client. (LEGACY I2C DRIVERS ONLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 */
115 int (*attach_adapter)(struct i2c_adapter *);
116 int (*detach_adapter)(struct i2c_adapter *);
117
David Brownell438d6c22006-12-10 21:21:31 +0100118 /* tells the driver that a client is about to be deleted & gives it
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 * the chance to remove its private data. Also, if the client struct
120 * has been dynamically allocated by the driver in the function above,
David Brownell7b4fbc52007-05-01 23:26:30 +0200121 * it must be freed here. (LEGACY I2C DRIVERS ONLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 */
123 int (*detach_client)(struct i2c_client *);
David Brownellf37dd802007-02-13 22:09:00 +0100124
David Brownell7b4fbc52007-05-01 23:26:30 +0200125 /* Standard driver model interfaces, for "new style" i2c drivers.
126 * With the driver model, device enumeration is NEVER done by drivers;
127 * it's done by infrastructure. (NEW STYLE DRIVERS ONLY)
128 */
129 int (*probe)(struct i2c_client *);
David Brownella1d9e6e2007-05-01 23:26:30 +0200130 int (*remove)(struct i2c_client *);
David Brownell7b4fbc52007-05-01 23:26:30 +0200131
David Brownellf37dd802007-02-13 22:09:00 +0100132 /* driver model interfaces that don't relate to enumeration */
133 void (*shutdown)(struct i2c_client *);
134 int (*suspend)(struct i2c_client *, pm_message_t mesg);
135 int (*resume)(struct i2c_client *);
136
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 /* a ioctl like command that can be used to perform specific functions
138 * with the device.
139 */
140 int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
141
142 struct device_driver driver;
143 struct list_head list;
144};
145#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
146
David Brownell2096b952007-05-01 23:26:28 +0200147#define I2C_NAME_SIZE 20
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148
David Brownell2096b952007-05-01 23:26:28 +0200149/**
150 * struct i2c_client - represent an I2C slave device
David Brownelld64f73b2007-07-12 14:12:28 +0200151 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
152 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
David Brownell2096b952007-05-01 23:26:28 +0200153 * @addr: Address used on the I2C bus connected to the parent adapter.
154 * @name: Indicates the type of the device, usually a chip name that's
155 * generic enough to hide second-sourcing and compatible revisions.
David Brownelld64f73b2007-07-12 14:12:28 +0200156 * @adapter: manages the bus segment hosting this I2C device
Randy Dunlapaa3481d2007-07-31 00:39:02 -0700157 * @driver: device's driver, hence pointer to access routines
158 * @usage_count: counts current number of users of this client
David Brownell2096b952007-05-01 23:26:28 +0200159 * @dev: Driver model device node for the slave.
David Brownelld64f73b2007-07-12 14:12:28 +0200160 * @irq: indicates the IRQ generated by this device (if any)
David Brownell7b4fbc52007-05-01 23:26:30 +0200161 * @driver_name: Identifies new-style driver used with this device; also
162 * used as the module name for hotplug/coldplug modprobe support.
Randy Dunlapaa3481d2007-07-31 00:39:02 -0700163 * @list: list of active/busy clients
164 * @released: used to synchronize client releases & detaches and references
David Brownell2096b952007-05-01 23:26:28 +0200165 *
166 * An i2c_client identifies a single device (i.e. chip) connected to an
David Brownelld64f73b2007-07-12 14:12:28 +0200167 * i2c bus. The behaviour exposed to Linux is defined by the driver
168 * managing the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 */
170struct i2c_client {
David Brownell2096b952007-05-01 23:26:28 +0200171 unsigned short flags; /* div., see below */
David Brownell438d6c22006-12-10 21:21:31 +0100172 unsigned short addr; /* chip address - NOTE: 7bit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 /* addresses are stored in the */
Jean Delvare50718602005-07-20 00:02:32 +0200174 /* _LOWER_ 7 bits */
David Brownell2096b952007-05-01 23:26:28 +0200175 char name[I2C_NAME_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 struct i2c_adapter *adapter; /* the adapter we sit on */
177 struct i2c_driver *driver; /* and our access routines */
178 int usage_count; /* How many accesses currently */
179 /* to the client */
180 struct device dev; /* the device structure */
David Brownell9c1600e2007-05-01 23:26:31 +0200181 int irq; /* irq issued by device (or -1) */
David Brownell7b4fbc52007-05-01 23:26:30 +0200182 char driver_name[KOBJ_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 struct list_head list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 struct completion released;
185};
186#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
187
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500188static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
189{
Mark M. Hoffmand75d53c2007-07-12 14:12:28 +0200190 struct device * const dev = container_of(kobj, struct device, kobj);
191 return to_i2c_client(dev);
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500192}
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194static inline void *i2c_get_clientdata (struct i2c_client *dev)
195{
196 return dev_get_drvdata (&dev->dev);
197}
198
199static inline void i2c_set_clientdata (struct i2c_client *dev, void *data)
200{
201 dev_set_drvdata (&dev->dev, data);
202}
203
David Brownell9c1600e2007-05-01 23:26:31 +0200204/**
205 * struct i2c_board_info - template for device creation
206 * @driver_name: identifies the driver to be bound to the device
207 * @type: optional chip type information, to initialize i2c_client.name
208 * @flags: to initialize i2c_client.flags
209 * @addr: stored in i2c_client.addr
210 * @platform_data: stored in i2c_client.dev.platform_data
211 * @irq: stored in i2c_client.irq
David Brownelld64f73b2007-07-12 14:12:28 +0200212 *
David Brownell9c1600e2007-05-01 23:26:31 +0200213 * I2C doesn't actually support hardware probing, although controllers and
214 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
215 * a device at a given address. Drivers commonly need more information than
216 * that, such as chip type, configuration, associated IRQ, and so on.
217 *
218 * i2c_board_info is used to build tables of information listing I2C devices
219 * that are present. This information is used to grow the driver model tree
220 * for "new style" I2C drivers. For mainboards this is done statically using
David Brownelld64f73b2007-07-12 14:12:28 +0200221 * i2c_register_board_info(); bus numbers identify adapters that aren't
David Brownell9c1600e2007-05-01 23:26:31 +0200222 * yet available. For add-on boards, i2c_new_device() does this dynamically
223 * with the adapter already known.
224 */
225struct i2c_board_info {
226 char driver_name[KOBJ_NAME_LEN];
227 char type[I2C_NAME_SIZE];
228 unsigned short flags;
229 unsigned short addr;
230 void *platform_data;
231 int irq;
232};
233
234/**
235 * I2C_BOARD_INFO - macro used to list an i2c device and its driver
236 * @driver: identifies the driver to use with the device
237 * @dev_addr: the device's address on the bus.
238 *
239 * This macro initializes essential fields of a struct i2c_board_info,
240 * declaring what has been provided on a particular board. Optional
241 * fields (such as the chip type, its associated irq, or device-specific
242 * platform_data) are provided using conventional syntax.
243 */
244#define I2C_BOARD_INFO(driver,dev_addr) \
245 .driver_name = (driver), .addr = (dev_addr)
246
247
248/* Add-on boards should register/unregister their devices; e.g. a board
249 * with integrated I2C, a config eeprom, sensors, and a codec that's
250 * used in conjunction with the primary hardware.
251 */
252extern struct i2c_client *
253i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
254
Jean Delvare12b5053a2007-05-01 23:26:31 +0200255/* If you don't know the exact address of an I2C device, use this variant
256 * instead, which can probe for device presence in a list of possible
257 * addresses.
258 */
259extern struct i2c_client *
260i2c_new_probed_device(struct i2c_adapter *adap,
261 struct i2c_board_info *info,
262 unsigned short const *addr_list);
263
David Brownell9c1600e2007-05-01 23:26:31 +0200264extern void i2c_unregister_device(struct i2c_client *);
265
266/* Mainboard arch_initcall() code should register all its I2C devices.
267 * This is done at arch_initcall time, before declaring any i2c adapters.
268 * Modules for add-on boards must use other calls.
269 */
270extern int
271i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned n);
272
273
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274/*
275 * The following structs are for those who like to implement new bus drivers:
276 * i2c_algorithm is the interface to a class of hardware solutions which can
277 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
278 * to name two of the most common.
279 */
280struct i2c_algorithm {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 /* If an adapter algorithm can't do I2C-level access, set master_xfer
David Brownell438d6c22006-12-10 21:21:31 +0100282 to NULL. If an adapter algorithm can do SMBus access, set
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 smbus_xfer. If set to NULL, the SMBus protocol is simulated
284 using common I2C messages */
Jean Delvare8ced8ee2006-07-01 17:12:53 +0200285 /* master_xfer should return the number of messages successfully
286 processed, or a negative value on error */
David Brownell438d6c22006-12-10 21:21:31 +0100287 int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg *msgs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 int num);
David Brownell438d6c22006-12-10 21:21:31 +0100289 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 unsigned short flags, char read_write,
291 u8 command, int size, union i2c_smbus_data * data);
292
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 /* To determine what the adapter supports */
294 u32 (*functionality) (struct i2c_adapter *);
295};
296
297/*
298 * i2c_adapter is the structure used to identify a physical i2c bus along
299 * with the access algorithms necessary to access it.
300 */
301struct i2c_adapter {
302 struct module *owner;
Jean Delvare020789e2005-08-13 13:04:32 +0200303 unsigned int id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 unsigned int class;
David Brownellaf71ff62006-09-03 22:37:11 +0200305 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 void *algo_data;
307
308 /* --- administration stuff. */
309 int (*client_register)(struct i2c_client *);
310 int (*client_unregister)(struct i2c_client *);
311
312 /* data fields that are valid for all devices */
Jiri Kosina6ea23032006-12-10 21:21:30 +0100313 u8 level; /* nesting level for lockdep */
Ingo Molnar5c085d32006-01-18 23:16:04 +0100314 struct mutex bus_lock;
315 struct mutex clist_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
317 int timeout;
318 int retries;
319 struct device dev; /* the adapter device */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 int nr;
322 struct list_head clients;
323 struct list_head list;
David Brownell2096b952007-05-01 23:26:28 +0200324 char name[48];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 struct completion dev_released;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326};
David Brownellef2c83212007-05-01 23:26:28 +0200327#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328
329static inline void *i2c_get_adapdata (struct i2c_adapter *dev)
330{
331 return dev_get_drvdata (&dev->dev);
332}
333
334static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data)
335{
336 dev_set_drvdata (&dev->dev, data);
337}
338
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339/*flags for the client struct: */
David Brownell3bbb8352007-10-13 23:56:29 +0200340#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
341#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
342 /* Must equal I2C_M_TEN below */
343#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344
345/* i2c adapter classes (bitmask) */
346#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
347#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
348#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
349#define I2C_CLASS_DDC (1<<3) /* i2c-matroxfb ? */
350#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */
351#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */
352#define I2C_CLASS_SOUND (1<<6) /* sound devices */
353#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */
354
355/* i2c_client_address_data is the struct for holding default client
356 * addresses for a driver and for the parameters supplied on the
357 * command line
358 */
359struct i2c_client_address_data {
360 unsigned short *normal_i2c;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 unsigned short *probe;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 unsigned short *ignore;
Jean Delvare9fc6adf2005-07-31 21:20:43 +0200363 unsigned short **forces;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364};
365
366/* Internal numbers to terminate lists */
367#define I2C_CLIENT_END 0xfffeU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
369/* The numbers to use to set I2C bus address */
370#define ANY_I2C_BUS 0xffff
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371
372
373/* ----- functions exported by i2c.o */
374
375/* administration...
376 */
377extern int i2c_add_adapter(struct i2c_adapter *);
378extern int i2c_del_adapter(struct i2c_adapter *);
David Brownell6e13e642007-05-01 23:26:31 +0200379extern int i2c_add_numbered_adapter(struct i2c_adapter *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800381extern int i2c_register_driver(struct module *, struct i2c_driver *);
Jean Delvareb3e82092007-05-01 23:26:32 +0200382extern void i2c_del_driver(struct i2c_driver *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800384static inline int i2c_add_driver(struct i2c_driver *driver)
385{
386 return i2c_register_driver(THIS_MODULE, driver);
387}
388
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389extern int i2c_attach_client(struct i2c_client *);
390extern int i2c_detach_client(struct i2c_client *);
391
Jean Delvare482c7882005-11-26 21:06:08 +0100392/* Should be used to make sure that client-struct is valid and that it
393 is okay to access the i2c-client.
Jean Delvarecf02df72005-11-26 21:03:41 +0100394 returns -ENODEV if client has gone in the meantime */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395extern int i2c_use_client(struct i2c_client *);
396extern int i2c_release_client(struct i2c_client *);
397
398/* call the i2c_client->command() of all attached clients with
399 * the given arguments */
400extern void i2c_clients_command(struct i2c_adapter *adap,
401 unsigned int cmd, void *arg);
402
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403/* Detect function. It iterates over all possible addresses itself.
404 * It will only call found_proc if some client is connected at the
405 * specific address (unless a 'force' matched);
406 */
David Brownell438d6c22006-12-10 21:21:31 +0100407extern int i2c_probe(struct i2c_adapter *adapter,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 struct i2c_client_address_data *address_data,
409 int (*found_proc) (struct i2c_adapter *, int, int));
410
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411extern struct i2c_adapter* i2c_get_adapter(int id);
412extern void i2c_put_adapter(struct i2c_adapter *adap);
413
414
415/* Return the functionality mask */
416static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
417{
418 return adap->algo->functionality(adap);
419}
420
421/* Return 1 if adapter supports everything we need, 0 if not. */
422static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
423{
424 return (func & i2c_get_functionality(adap)) == func;
425}
426
Jean Delvarecdcb1922005-07-28 23:09:40 +0200427/* Return id number for a specific adapter */
428static inline int i2c_adapter_id(struct i2c_adapter *adap)
429{
430 return adap->nr;
431}
David Woodhousea1b92982006-04-25 14:14:52 +0100432#endif /* __KERNEL__ */
Jean Delvarecdcb1922005-07-28 23:09:40 +0200433
David Brownella64ec072007-10-13 23:56:31 +0200434/**
435 * struct i2c_msg - an I2C transaction segment beginning with START
436 * @addr: Slave address, either seven or ten bits. When this is a ten
437 * bit address, I2C_M_TEN must be set in @flags and the adapter
438 * must support I2C_FUNC_10BIT_ADDR.
439 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
440 * provided unless the adapter exported the relevant I2C_FUNC_*
441 * flags through i2c_check_functionality().
442 * @len: Number of data bytes in @buf being read from or written to the
443 * I2C slave address. For read transactions where I2C_M_RECV_LEN
444 * is set, the caller guarantees that this buffer can hold up to
445 * 32 bytes in addition to the initial length byte sent by the
446 * slave (plus, if used, the SMBus PEC); and this value will be
447 * incremented by the number of block data bytes received.
448 * @buf: The buffer into which data is read, or from which it's written.
449 *
450 * An i2c_msg is the low level representation of one segment of an I2C
451 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
452 * to userspace from i2c-dev, and to I2C adapter drivers through the
453 * @i2c_adapter.@master_xfer() method.
454 *
455 * Except when I2C "protocol mangling" is used, all I2C adapters implement
456 * the standard rules for I2C transactions. Each transaction begins with a
457 * START. That is followed by the slave address, and a bit encoding read
458 * versus write. Then follow all the data bytes, possibly including a byte
459 * with SMBus PEC. The transfer terminates with a NAK, or when all those
460 * bytes have been transferred and ACKed. If this is the last message in a
461 * group, it is followed by a STOP. Otherwise it is followed by the next
462 * @i2c_msg transaction segment, beginning with a (repeated) START.
463 *
464 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
465 * passing certain @flags may have changed those standard protocol behaviors.
466 * Those flags are only for use with broken/nonconforming slaves, and with
467 * adapters which are known to support the specific mangling options they
468 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 */
470struct i2c_msg {
471 __u16 addr; /* slave address */
David Brownell438d6c22006-12-10 21:21:31 +0100472 __u16 flags;
David Brownella64ec072007-10-13 23:56:31 +0200473#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
474#define I2C_M_RD 0x0001 /* read data, from slave to master */
475#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
476#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
477#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
478#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
479#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
David Brownell438d6c22006-12-10 21:21:31 +0100480 __u16 len; /* msg length */
481 __u8 *buf; /* pointer to msg data */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482};
483
484/* To determine what functionality is present */
485
486#define I2C_FUNC_I2C 0x00000001
487#define I2C_FUNC_10BIT_ADDR 0x00000002
488#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART,..} */
David Brownell6662cbb2007-10-13 23:56:33 +0200489#define I2C_FUNC_SMBUS_PEC 0x00000008
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
David Brownell438d6c22006-12-10 21:21:31 +0100491#define I2C_FUNC_SMBUS_QUICK 0x00010000
492#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
493#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
494#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
495#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
496#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
497#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
498#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
499#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
500#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
502#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
503#define I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 0x10000000 /* I2C-like block xfer */
504#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2 0x20000000 /* w/ 2-byte reg. addr. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505
506#define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
507 I2C_FUNC_SMBUS_WRITE_BYTE)
508#define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
509 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
510#define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
511 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
512#define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
513 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
514#define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
515 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
516#define I2C_FUNC_SMBUS_I2C_BLOCK_2 (I2C_FUNC_SMBUS_READ_I2C_BLOCK_2 | \
517 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK_2)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518
519#define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
520 I2C_FUNC_SMBUS_BYTE | \
521 I2C_FUNC_SMBUS_BYTE_DATA | \
522 I2C_FUNC_SMBUS_WORD_DATA | \
523 I2C_FUNC_SMBUS_PROC_CALL | \
524 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
David Brownell6662cbb2007-10-13 23:56:33 +0200525 I2C_FUNC_SMBUS_I2C_BLOCK | \
526 I2C_FUNC_SMBUS_PEC)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
David Brownell438d6c22006-12-10 21:21:31 +0100528/*
529 * Data for SMBus Messages
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 */
David Brownell438d6c22006-12-10 21:21:31 +0100531#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532union i2c_smbus_data {
533 __u8 byte;
534 __u16 word;
Hideki Iwamoto332bf922005-09-25 16:56:43 +0200535 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
Jean Delvare421ef472005-10-26 21:28:55 +0200536 /* and one more for user-space compatibility */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537};
538
539/* smbus_access read or write markers */
540#define I2C_SMBUS_READ 1
541#define I2C_SMBUS_WRITE 0
542
David Brownell438d6c22006-12-10 21:21:31 +0100543/* SMBus transaction types (size parameter in the above functions)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
545#define I2C_SMBUS_QUICK 0
546#define I2C_SMBUS_BYTE 1
David Brownell438d6c22006-12-10 21:21:31 +0100547#define I2C_SMBUS_BYTE_DATA 2
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548#define I2C_SMBUS_WORD_DATA 3
549#define I2C_SMBUS_PROC_CALL 4
550#define I2C_SMBUS_BLOCK_DATA 5
Jean Delvare4b2643d2007-07-12 14:12:29 +0200551#define I2C_SMBUS_I2C_BLOCK_BROKEN 6
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
Jean Delvare4b2643d2007-07-12 14:12:29 +0200553#define I2C_SMBUS_I2C_BLOCK_DATA 8
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554
555
David Woodhousea1b92982006-04-25 14:14:52 +0100556#ifdef __KERNEL__
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558/* These defines are used for probing i2c client addresses */
559/* The length of the option lists */
560#define I2C_CLIENT_MAX_OPTS 48
561
562/* Default fill of many variables */
563#define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
564 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
565 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
566 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
567 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
568 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
569 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
570 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
571 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
572 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
573 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
574 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
575 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
576 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
577 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
578 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}
579
580/* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
581 module header */
582
583#define I2C_CLIENT_MODULE_PARM(var,desc) \
584 static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
585 static unsigned int var##_num; \
586 module_param_array(var, short, &var##_num, 0); \
587 MODULE_PARM_DESC(var,desc)
588
Jean Delvaref4b50262005-07-31 21:49:03 +0200589#define I2C_CLIENT_MODULE_PARM_FORCE(name) \
590I2C_CLIENT_MODULE_PARM(force_##name, \
591 "List of adapter,address pairs which are " \
592 "unquestionably assumed to contain a `" \
593 # name "' chip")
594
595
596#define I2C_CLIENT_INSMOD_COMMON \
597I2C_CLIENT_MODULE_PARM(probe, "List of adapter,address pairs to scan " \
598 "additionally"); \
599I2C_CLIENT_MODULE_PARM(ignore, "List of adapter,address pairs not to " \
600 "scan"); \
601static struct i2c_client_address_data addr_data = { \
602 .normal_i2c = normal_i2c, \
603 .probe = probe, \
604 .ignore = ignore, \
605 .forces = forces, \
606}
607
608/* These are the ones you want to use in your own drivers. Pick the one
609 which matches the number of devices the driver differenciates between. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610#define I2C_CLIENT_INSMOD \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 I2C_CLIENT_MODULE_PARM(force, \
612 "List of adapter,address pairs to boldly assume " \
613 "to be present"); \
Jean Delvaref4b50262005-07-31 21:49:03 +0200614 static unsigned short *forces[] = { \
Jean Delvare9fc6adf2005-07-31 21:20:43 +0200615 force, \
616 NULL \
617 }; \
Jean Delvaref4b50262005-07-31 21:49:03 +0200618I2C_CLIENT_INSMOD_COMMON
619
620#define I2C_CLIENT_INSMOD_1(chip1) \
621enum chips { any_chip, chip1 }; \
622I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
623 "boldly assume to be present"); \
624I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
625static unsigned short *forces[] = { force, force_##chip1, NULL }; \
626I2C_CLIENT_INSMOD_COMMON
627
628#define I2C_CLIENT_INSMOD_2(chip1, chip2) \
629enum chips { any_chip, chip1, chip2 }; \
630I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
631 "boldly assume to be present"); \
632I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
633I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
634static unsigned short *forces[] = { force, force_##chip1, \
635 force_##chip2, NULL }; \
636I2C_CLIENT_INSMOD_COMMON
637
638#define I2C_CLIENT_INSMOD_3(chip1, chip2, chip3) \
639enum chips { any_chip, chip1, chip2, chip3 }; \
640I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
641 "boldly assume to be present"); \
642I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
643I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
644I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
645static unsigned short *forces[] = { force, force_##chip1, \
646 force_##chip2, force_##chip3, \
647 NULL }; \
648I2C_CLIENT_INSMOD_COMMON
649
650#define I2C_CLIENT_INSMOD_4(chip1, chip2, chip3, chip4) \
651enum chips { any_chip, chip1, chip2, chip3, chip4 }; \
652I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
653 "boldly assume to be present"); \
654I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
655I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
656I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
657I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
658static unsigned short *forces[] = { force, force_##chip1, \
659 force_##chip2, force_##chip3, \
660 force_##chip4, NULL}; \
661I2C_CLIENT_INSMOD_COMMON
662
663#define I2C_CLIENT_INSMOD_5(chip1, chip2, chip3, chip4, chip5) \
664enum chips { any_chip, chip1, chip2, chip3, chip4, chip5 }; \
665I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
666 "boldly assume to be present"); \
667I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
668I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
669I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
670I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
671I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
672static unsigned short *forces[] = { force, force_##chip1, \
673 force_##chip2, force_##chip3, \
674 force_##chip4, force_##chip5, \
675 NULL }; \
676I2C_CLIENT_INSMOD_COMMON
677
678#define I2C_CLIENT_INSMOD_6(chip1, chip2, chip3, chip4, chip5, chip6) \
679enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6 }; \
680I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
681 "boldly assume to be present"); \
682I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
683I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
684I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
685I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
686I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
687I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
688static unsigned short *forces[] = { force, force_##chip1, \
689 force_##chip2, force_##chip3, \
690 force_##chip4, force_##chip5, \
691 force_##chip6, NULL }; \
692I2C_CLIENT_INSMOD_COMMON
693
694#define I2C_CLIENT_INSMOD_7(chip1, chip2, chip3, chip4, chip5, chip6, chip7) \
695enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
696 chip7 }; \
697I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
698 "boldly assume to be present"); \
699I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
700I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
701I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
702I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
703I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
704I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
705I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
706static unsigned short *forces[] = { force, force_##chip1, \
707 force_##chip2, force_##chip3, \
708 force_##chip4, force_##chip5, \
709 force_##chip6, force_##chip7, \
710 NULL }; \
711I2C_CLIENT_INSMOD_COMMON
712
713#define I2C_CLIENT_INSMOD_8(chip1, chip2, chip3, chip4, chip5, chip6, chip7, chip8) \
714enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \
715 chip7, chip8 }; \
716I2C_CLIENT_MODULE_PARM(force, "List of adapter,address pairs to " \
717 "boldly assume to be present"); \
718I2C_CLIENT_MODULE_PARM_FORCE(chip1); \
719I2C_CLIENT_MODULE_PARM_FORCE(chip2); \
720I2C_CLIENT_MODULE_PARM_FORCE(chip3); \
721I2C_CLIENT_MODULE_PARM_FORCE(chip4); \
722I2C_CLIENT_MODULE_PARM_FORCE(chip5); \
723I2C_CLIENT_MODULE_PARM_FORCE(chip6); \
724I2C_CLIENT_MODULE_PARM_FORCE(chip7); \
725I2C_CLIENT_MODULE_PARM_FORCE(chip8); \
726static unsigned short *forces[] = { force, force_##chip1, \
727 force_##chip2, force_##chip3, \
728 force_##chip4, force_##chip5, \
729 force_##chip6, force_##chip7, \
730 force_##chip8, NULL }; \
731I2C_CLIENT_INSMOD_COMMON
David Woodhousea1b92982006-04-25 14:14:52 +0100732#endif /* __KERNEL__ */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733#endif /* _LINUX_I2C_H */