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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>
Grant Likelyd12d42f2010-04-13 16:12:28 -070037#include <linux/of.h> /* for struct device_node */
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
Jon Smirle9ca9eb2008-07-14 22:38:35 +020039extern struct bus_type i2c_bus_type;
Michael Lawnick08263742010-08-11 18:21:02 +020040extern struct device_type i2c_adapter_type;
Jon Smirle9ca9eb2008-07-14 22:38:35 +020041
Linus Torvalds1da177e2005-04-16 15:20:36 -070042/* --- General options ------------------------------------------------ */
43
44struct i2c_msg;
45struct i2c_algorithm;
46struct i2c_adapter;
47struct i2c_client;
48struct i2c_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049union i2c_smbus_data;
Jean Delvare4735c982008-07-14 22:38:36 +020050struct i2c_board_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Jean Delvare23af8402009-06-19 16:58:20 +020052#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070053/*
54 * The master routines are the ones normally used to transmit data to devices
David Brownell438d6c22006-12-10 21:21:31 +010055 * on a bus (or read from them). Apart from two basic transfer functions to
56 * transmit one message at a time, a more complex version can be used to
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 * transmit an arbitrary number of messages without interruption.
Zhangfei Gao0c43ea52010-03-02 12:23:49 +010058 * @count must be be less than 64k since msg.len is u16.
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 */
Jean Delvare3ae70de2008-10-22 20:21:32 +020060extern int i2c_master_send(struct i2c_client *client, const char *buf,
61 int count);
62extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
64/* Transfer num messages.
65 */
Jean Delvare3ae70de2008-10-22 20:21:32 +020066extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
67 int num);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69/* This is the very generalized SMBus access routine. You probably do not
70 want to use this, though; one of the functions below may be much easier,
David Brownell438d6c22006-12-10 21:21:31 +010071 and probably just as fast.
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 Note that we use i2c_adapter here, because you do not need a specific
73 smbus adapter to call this function. */
Jean Delvare3ae70de2008-10-22 20:21:32 +020074extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
75 unsigned short flags, char read_write, u8 command,
76 int size, union i2c_smbus_data *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78/* Now follow the 'nice' access routines. These also document the calling
Jean Delvareae7193f2008-07-14 22:38:24 +020079 conventions of i2c_smbus_xfer. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070080
Jean Delvare3ae70de2008-10-22 20:21:32 +020081extern s32 i2c_smbus_read_byte(struct i2c_client *client);
82extern s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value);
83extern s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);
84extern s32 i2c_smbus_write_byte_data(struct i2c_client *client,
85 u8 command, u8 value);
86extern s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command);
87extern s32 i2c_smbus_write_word_data(struct i2c_client *client,
88 u8 command, u16 value);
Jean Delvareb86a1bc2007-05-01 23:26:34 +020089/* Returns the number of read bytes */
90extern s32 i2c_smbus_read_block_data(struct i2c_client *client,
91 u8 command, u8 *values);
Jean Delvare3ae70de2008-10-22 20:21:32 +020092extern s32 i2c_smbus_write_block_data(struct i2c_client *client,
93 u8 command, u8 length, const u8 *values);
Jean Delvare31ec5bc2005-10-08 00:04:13 +020094/* Returns the number of read bytes */
Jean Delvare3ae70de2008-10-22 20:21:32 +020095extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client,
Jean Delvare4b2643d2007-07-12 14:12:29 +020096 u8 command, u8 length, u8 *values);
Jean Delvare3ae70de2008-10-22 20:21:32 +020097extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client,
Jean Delvare21bbd692006-01-09 15:19:18 +110098 u8 command, u8 length,
Krzysztof Halasa46f5ed72006-06-12 21:42:20 +020099 const u8 *values);
Jean Delvare23af8402009-06-19 16:58:20 +0200100#endif /* I2C */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Jean Delvare4735c982008-07-14 22:38:36 +0200102/**
103 * struct i2c_driver - represent an I2C device driver
104 * @class: What kind of i2c device we instantiate (for detect)
Jean Delvare96e21e42008-08-28 08:33:23 +0200105 * @attach_adapter: Callback for bus addition (for legacy drivers)
106 * @detach_adapter: Callback for bus removal (for legacy drivers)
Jean Delvare729d6dd2009-06-19 16:58:18 +0200107 * @probe: Callback for device binding
108 * @remove: Callback for device unbinding
Jean Delvare96e21e42008-08-28 08:33:23 +0200109 * @shutdown: Callback for device shutdown
110 * @suspend: Callback for device suspend
111 * @resume: Callback for device resume
Randy Dunlap72d2e9f2010-08-09 16:37:16 -0700112 * @alert: Alert callback, for example for the SMBus alert protocol
Jean Delvare96e21e42008-08-28 08:33:23 +0200113 * @command: Callback for bus-wide signaling (optional)
114 * @driver: Device driver model driver
115 * @id_table: List of I2C devices supported by this driver
Jean Delvare4735c982008-07-14 22:38:36 +0200116 * @detect: Callback for device detection
Jean Delvarec3813d62009-12-14 21:17:25 +0100117 * @address_list: The I2C addresses to probe (for detect)
Jean Delvare4735c982008-07-14 22:38:36 +0200118 * @clients: List of detected clients we created (for i2c-core use only)
Laurent Riffard35d8b2e2005-11-26 20:34:05 +0100119 *
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.
Jean Delvare4735c982008-07-14 22:38:36 +0200122 *
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.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140struct i2c_driver {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 unsigned int class;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Jean Delvare729d6dd2009-06-19 16:58:18 +0200143 /* Notifies the driver that a new bus has appeared or is about to be
144 * removed. You should avoid using this if you can, it will probably
145 * be removed in a near future.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 */
147 int (*attach_adapter)(struct i2c_adapter *);
148 int (*detach_adapter)(struct i2c_adapter *);
149
Jean Delvare729d6dd2009-06-19 16:58:18 +0200150 /* Standard driver model interfaces */
Jean Delvared2653e92008-04-29 23:11:39 +0200151 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
David Brownella1d9e6e2007-05-01 23:26:30 +0200152 int (*remove)(struct i2c_client *);
David Brownell7b4fbc52007-05-01 23:26:30 +0200153
David Brownellf37dd802007-02-13 22:09:00 +0100154 /* driver model interfaces that don't relate to enumeration */
155 void (*shutdown)(struct i2c_client *);
156 int (*suspend)(struct i2c_client *, pm_message_t mesg);
157 int (*resume)(struct i2c_client *);
158
Jean Delvareb5527a72010-03-02 12:23:42 +0100159 /* Alert callback, for example for the SMBus alert protocol.
160 * The format and meaning of the data value depends on the protocol.
161 * For the SMBus alert protocol, there is a single bit of data passed
162 * as the alert response's low bit ("event flag").
163 */
164 void (*alert)(struct i2c_client *, unsigned int data);
165
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 /* a ioctl like command that can be used to perform specific functions
167 * with the device.
168 */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200169 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
171 struct device_driver driver;
Jean Delvared2653e92008-04-29 23:11:39 +0200172 const struct i2c_device_id *id_table;
Jean Delvare4735c982008-07-14 22:38:36 +0200173
174 /* Device detection callback for automatic device creation */
Jean Delvare310ec792009-12-14 21:17:23 +0100175 int (*detect)(struct i2c_client *, struct i2c_board_info *);
Jean Delvarec3813d62009-12-14 21:17:25 +0100176 const unsigned short *address_list;
Jean Delvare4735c982008-07-14 22:38:36 +0200177 struct list_head clients;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178};
179#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
180
David Brownell2096b952007-05-01 23:26:28 +0200181/**
182 * struct i2c_client - represent an I2C slave device
David Brownelld64f73b2007-07-12 14:12:28 +0200183 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
184 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
David Brownell2096b952007-05-01 23:26:28 +0200185 * @addr: Address used on the I2C bus connected to the parent adapter.
186 * @name: Indicates the type of the device, usually a chip name that's
187 * generic enough to hide second-sourcing and compatible revisions.
David Brownelld64f73b2007-07-12 14:12:28 +0200188 * @adapter: manages the bus segment hosting this I2C device
Randy Dunlapaa3481d2007-07-31 00:39:02 -0700189 * @driver: device's driver, hence pointer to access routines
David Brownell2096b952007-05-01 23:26:28 +0200190 * @dev: Driver model device node for the slave.
David Brownelld64f73b2007-07-12 14:12:28 +0200191 * @irq: indicates the IRQ generated by this device (if any)
Jean Delvare99cd8e22009-06-19 16:58:20 +0200192 * @detected: member of an i2c_driver.clients list or i2c-core's
193 * userspace_devices list
David Brownell2096b952007-05-01 23:26:28 +0200194 *
195 * An i2c_client identifies a single device (i.e. chip) connected to an
David Brownelld64f73b2007-07-12 14:12:28 +0200196 * i2c bus. The behaviour exposed to Linux is defined by the driver
197 * managing the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 */
199struct i2c_client {
David Brownell2096b952007-05-01 23:26:28 +0200200 unsigned short flags; /* div., see below */
David Brownell438d6c22006-12-10 21:21:31 +0100201 unsigned short addr; /* chip address - NOTE: 7bit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 /* addresses are stored in the */
Jean Delvare50718602005-07-20 00:02:32 +0200203 /* _LOWER_ 7 bits */
David Brownell2096b952007-05-01 23:26:28 +0200204 char name[I2C_NAME_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 struct i2c_adapter *adapter; /* the adapter we sit on */
206 struct i2c_driver *driver; /* and our access routines */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 struct device dev; /* the device structure */
Wolfram Sang8e29da92008-07-01 22:38:18 +0200208 int irq; /* irq issued by device */
Jean Delvare4735c982008-07-14 22:38:36 +0200209 struct list_head detected;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210};
211#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
212
David Brownell9b766b82008-01-27 18:14:51 +0100213extern struct i2c_client *i2c_verify_client(struct device *dev);
214
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500215static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
216{
Mark M. Hoffmand75d53c2007-07-12 14:12:28 +0200217 struct device * const dev = container_of(kobj, struct device, kobj);
218 return to_i2c_client(dev);
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500219}
220
Jean Delvare7d1d8992008-10-22 20:21:31 +0200221static inline void *i2c_get_clientdata(const struct i2c_client *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200223 return dev_get_drvdata(&dev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224}
225
Jean Delvare3ae70de2008-10-22 20:21:32 +0200226static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200228 dev_set_drvdata(&dev->dev, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229}
230
David Brownell9c1600e2007-05-01 23:26:31 +0200231/**
232 * struct i2c_board_info - template for device creation
Jean Delvareeb8a7902008-05-18 20:49:41 +0200233 * @type: chip type, to initialize i2c_client.name
David Brownell9c1600e2007-05-01 23:26:31 +0200234 * @flags: to initialize i2c_client.flags
235 * @addr: stored in i2c_client.addr
236 * @platform_data: stored in i2c_client.dev.platform_data
Anton Vorontsov11f1f2a2008-10-22 20:21:33 +0200237 * @archdata: copied into i2c_client.dev.archdata
Randy Dunlap72d2e9f2010-08-09 16:37:16 -0700238 * @of_node: pointer to OpenFirmware device node
David Brownell9c1600e2007-05-01 23:26:31 +0200239 * @irq: stored in i2c_client.irq
David Brownelld64f73b2007-07-12 14:12:28 +0200240 *
David Brownell9c1600e2007-05-01 23:26:31 +0200241 * I2C doesn't actually support hardware probing, although controllers and
242 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
243 * a device at a given address. Drivers commonly need more information than
244 * that, such as chip type, configuration, associated IRQ, and so on.
245 *
246 * i2c_board_info is used to build tables of information listing I2C devices
Jean Delvare729d6dd2009-06-19 16:58:18 +0200247 * that are present. This information is used to grow the driver model tree.
248 * For mainboards this is done statically using i2c_register_board_info();
249 * bus numbers identify adapters that aren't yet available. For add-on boards,
250 * i2c_new_device() does this dynamically with the adapter already known.
David Brownell9c1600e2007-05-01 23:26:31 +0200251 */
252struct i2c_board_info {
David Brownell9c1600e2007-05-01 23:26:31 +0200253 char type[I2C_NAME_SIZE];
254 unsigned short flags;
255 unsigned short addr;
256 void *platform_data;
Anton Vorontsov11f1f2a2008-10-22 20:21:33 +0200257 struct dev_archdata *archdata;
Grant Likelyd12d42f2010-04-13 16:12:28 -0700258#ifdef CONFIG_OF
259 struct device_node *of_node;
260#endif
David Brownell9c1600e2007-05-01 23:26:31 +0200261 int irq;
262};
263
264/**
Jean Delvare3760f732008-04-29 23:11:40 +0200265 * I2C_BOARD_INFO - macro used to list an i2c device and its address
266 * @dev_type: identifies the device type
David Brownell9c1600e2007-05-01 23:26:31 +0200267 * @dev_addr: the device's address on the bus.
268 *
269 * This macro initializes essential fields of a struct i2c_board_info,
270 * declaring what has been provided on a particular board. Optional
Jean Delvare3760f732008-04-29 23:11:40 +0200271 * fields (such as associated irq, or device-specific platform_data)
272 * are provided using conventional syntax.
David Brownell9c1600e2007-05-01 23:26:31 +0200273 */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200274#define I2C_BOARD_INFO(dev_type, dev_addr) \
Ben Hutchingsc758e8c2009-04-13 17:02:14 +0200275 .type = dev_type, .addr = (dev_addr)
David Brownell9c1600e2007-05-01 23:26:31 +0200276
277
Jean Delvare23af8402009-06-19 16:58:20 +0200278#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
David Brownell9c1600e2007-05-01 23:26:31 +0200279/* Add-on boards should register/unregister their devices; e.g. a board
280 * with integrated I2C, a config eeprom, sensors, and a codec that's
281 * used in conjunction with the primary hardware.
282 */
283extern struct i2c_client *
284i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
285
Jean Delvare12b5053a2007-05-01 23:26:31 +0200286/* If you don't know the exact address of an I2C device, use this variant
287 * instead, which can probe for device presence in a list of possible
Jean Delvare9a942412010-08-11 18:20:56 +0200288 * addresses. The "probe" callback function is optional. If it is provided,
289 * it must return 1 on successful probe, 0 otherwise. If it is not provided,
290 * a default probing method is used.
Jean Delvare12b5053a2007-05-01 23:26:31 +0200291 */
292extern struct i2c_client *
293i2c_new_probed_device(struct i2c_adapter *adap,
294 struct i2c_board_info *info,
Jean Delvare9a942412010-08-11 18:20:56 +0200295 unsigned short const *addr_list,
296 int (*probe)(struct i2c_adapter *, unsigned short addr));
Jean Delvare12b5053a2007-05-01 23:26:31 +0200297
Jean Delvared44f19d2010-08-11 18:20:57 +0200298/* Common custom probe functions */
299extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
300
David Brownelle9f13732008-01-27 18:14:52 +0100301/* For devices that use several addresses, use i2c_new_dummy() to make
302 * client handles for the extra addresses.
303 */
304extern struct i2c_client *
Jean Delvare60b129d2008-05-11 20:37:06 +0200305i2c_new_dummy(struct i2c_adapter *adap, u16 address);
David Brownelle9f13732008-01-27 18:14:52 +0100306
David Brownell9c1600e2007-05-01 23:26:31 +0200307extern void i2c_unregister_device(struct i2c_client *);
Jean Delvare23af8402009-06-19 16:58:20 +0200308#endif /* I2C */
David Brownell9c1600e2007-05-01 23:26:31 +0200309
310/* Mainboard arch_initcall() code should register all its I2C devices.
311 * This is done at arch_initcall time, before declaring any i2c adapters.
312 * Modules for add-on boards must use other calls.
313 */
David Brownell26386762008-02-24 20:03:42 +0100314#ifdef CONFIG_I2C_BOARDINFO
David Brownell9c1600e2007-05-01 23:26:31 +0200315extern int
Jean Delvare3ae70de2008-10-22 20:21:32 +0200316i2c_register_board_info(int busnum, struct i2c_board_info const *info,
317 unsigned n);
David Brownell26386762008-02-24 20:03:42 +0100318#else
319static inline int
Jean Delvare3ae70de2008-10-22 20:21:32 +0200320i2c_register_board_info(int busnum, struct i2c_board_info const *info,
321 unsigned n)
David Brownell26386762008-02-24 20:03:42 +0100322{
323 return 0;
324}
Jean Delvare23af8402009-06-19 16:58:20 +0200325#endif /* I2C_BOARDINFO */
David Brownell9c1600e2007-05-01 23:26:31 +0200326
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327/*
328 * The following structs are for those who like to implement new bus drivers:
329 * i2c_algorithm is the interface to a class of hardware solutions which can
330 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
331 * to name two of the most common.
332 */
333struct i2c_algorithm {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 /* If an adapter algorithm can't do I2C-level access, set master_xfer
David Brownell438d6c22006-12-10 21:21:31 +0100335 to NULL. If an adapter algorithm can do SMBus access, set
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 smbus_xfer. If set to NULL, the SMBus protocol is simulated
337 using common I2C messages */
Jean Delvare8ced8ee2006-07-01 17:12:53 +0200338 /* master_xfer should return the number of messages successfully
339 processed, or a negative value on error */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200340 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
341 int num);
David Brownell438d6c22006-12-10 21:21:31 +0100342 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
Jean Delvare3ae70de2008-10-22 20:21:32 +0200343 unsigned short flags, char read_write,
344 u8 command, int size, union i2c_smbus_data *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 /* To determine what the adapter supports */
347 u32 (*functionality) (struct i2c_adapter *);
348};
349
350/*
351 * i2c_adapter is the structure used to identify a physical i2c bus along
352 * with the access algorithms necessary to access it.
353 */
354struct i2c_adapter {
355 struct module *owner;
Jean Delvare020789e2005-08-13 13:04:32 +0200356 unsigned int id;
Wolfram Sang14f55f72008-10-22 20:21:30 +0200357 unsigned int class; /* classes to allow probing for */
David Brownellaf71ff62006-09-03 22:37:11 +0200358 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 void *algo_data;
360
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 /* data fields that are valid for all devices */
Mika Kuoppala194684e2009-12-06 17:06:22 +0100362 struct rt_mutex bus_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363
Jean Delvarecd97f392009-02-24 19:19:49 +0100364 int timeout; /* in jiffies */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 int retries;
366 struct device dev; /* the adapter device */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 int nr;
David Brownell2096b952007-05-01 23:26:28 +0200369 char name[48];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 struct completion dev_released;
Jean Delvare6629dcf2010-05-04 11:09:28 +0200371
Jean Delvaredafc50d2010-08-11 18:21:01 +0200372 struct mutex userspace_clients_lock;
Jean Delvare6629dcf2010-05-04 11:09:28 +0200373 struct list_head userspace_clients;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374};
David Brownellef2c83212007-05-01 23:26:28 +0200375#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
Jean Delvare7d1d8992008-10-22 20:21:31 +0200377static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200379 return dev_get_drvdata(&dev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380}
381
Jean Delvare3ae70de2008-10-22 20:21:32 +0200382static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200384 dev_set_drvdata(&dev->dev, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385}
386
Michael Lawnick08263742010-08-11 18:21:02 +0200387static inline int i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
388{
389 return adapter->dev.parent != NULL
390 && adapter->dev.parent->bus == &i2c_bus_type
391 && adapter->dev.parent->type == &i2c_adapter_type;
392}
393
Jean Delvarefe61e072010-08-11 18:20:58 +0200394/* Adapter locking functions, exported for shared pin cases */
395void i2c_lock_adapter(struct i2c_adapter *);
396void i2c_unlock_adapter(struct i2c_adapter *);
Jean Delvareafa08972009-11-07 13:10:46 +0100397
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398/*flags for the client struct: */
David Brownell3bbb8352007-10-13 23:56:29 +0200399#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
400#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
401 /* Must equal I2C_M_TEN below */
402#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
404/* i2c adapter classes (bitmask) */
405#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
406#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
407#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
Jean Delvarec1b6b4f2008-07-14 22:38:28 +0200408#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
Jean Delvare3401b2f2008-07-14 22:38:29 +0200409#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411/* Internal numbers to terminate lists */
412#define I2C_CLIENT_END 0xfffeU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413
414/* The numbers to use to set I2C bus address */
415#define ANY_I2C_BUS 0xffff
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
Hans Verkuilc7036672009-06-19 16:58:21 +0200417/* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
418#define I2C_ADDRS(addr, addrs...) \
419 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
420
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
422/* ----- functions exported by i2c.o */
423
424/* administration...
425 */
Jean Delvare23af8402009-06-19 16:58:20 +0200426#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427extern int i2c_add_adapter(struct i2c_adapter *);
428extern int i2c_del_adapter(struct i2c_adapter *);
David Brownell6e13e642007-05-01 23:26:31 +0200429extern int i2c_add_numbered_adapter(struct i2c_adapter *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800431extern int i2c_register_driver(struct module *, struct i2c_driver *);
Jean Delvareb3e82092007-05-01 23:26:32 +0200432extern void i2c_del_driver(struct i2c_driver *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800434static inline int i2c_add_driver(struct i2c_driver *driver)
435{
436 return i2c_register_driver(THIS_MODULE, driver);
437}
438
Jean Delvaree48d3312008-01-27 18:14:48 +0100439extern struct i2c_client *i2c_use_client(struct i2c_client *client);
440extern void i2c_release_client(struct i2c_client *client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441
442/* call the i2c_client->command() of all attached clients with
443 * the given arguments */
444extern void i2c_clients_command(struct i2c_adapter *adap,
445 unsigned int cmd, void *arg);
446
Jean Delvare3ae70de2008-10-22 20:21:32 +0200447extern struct i2c_adapter *i2c_get_adapter(int id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448extern void i2c_put_adapter(struct i2c_adapter *adap);
449
450
451/* Return the functionality mask */
452static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
453{
454 return adap->algo->functionality(adap);
455}
456
457/* Return 1 if adapter supports everything we need, 0 if not. */
458static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
459{
460 return (func & i2c_get_functionality(adap)) == func;
461}
462
Jean Delvare3ae70de2008-10-22 20:21:32 +0200463/* Return the adapter number for a specific adapter */
Jean Delvarecdcb1922005-07-28 23:09:40 +0200464static inline int i2c_adapter_id(struct i2c_adapter *adap)
465{
466 return adap->nr;
467}
Jean Delvare23af8402009-06-19 16:58:20 +0200468#endif /* I2C */
David Woodhousea1b92982006-04-25 14:14:52 +0100469#endif /* __KERNEL__ */
Jean Delvarecdcb1922005-07-28 23:09:40 +0200470
David Brownella64ec072007-10-13 23:56:31 +0200471/**
472 * struct i2c_msg - an I2C transaction segment beginning with START
473 * @addr: Slave address, either seven or ten bits. When this is a ten
474 * bit address, I2C_M_TEN must be set in @flags and the adapter
475 * must support I2C_FUNC_10BIT_ADDR.
476 * @flags: I2C_M_RD is handled by all adapters. No other flags may be
477 * provided unless the adapter exported the relevant I2C_FUNC_*
478 * flags through i2c_check_functionality().
479 * @len: Number of data bytes in @buf being read from or written to the
480 * I2C slave address. For read transactions where I2C_M_RECV_LEN
481 * is set, the caller guarantees that this buffer can hold up to
482 * 32 bytes in addition to the initial length byte sent by the
483 * slave (plus, if used, the SMBus PEC); and this value will be
484 * incremented by the number of block data bytes received.
485 * @buf: The buffer into which data is read, or from which it's written.
486 *
487 * An i2c_msg is the low level representation of one segment of an I2C
488 * transaction. It is visible to drivers in the @i2c_transfer() procedure,
489 * to userspace from i2c-dev, and to I2C adapter drivers through the
490 * @i2c_adapter.@master_xfer() method.
491 *
492 * Except when I2C "protocol mangling" is used, all I2C adapters implement
493 * the standard rules for I2C transactions. Each transaction begins with a
494 * START. That is followed by the slave address, and a bit encoding read
495 * versus write. Then follow all the data bytes, possibly including a byte
496 * with SMBus PEC. The transfer terminates with a NAK, or when all those
497 * bytes have been transferred and ACKed. If this is the last message in a
498 * group, it is followed by a STOP. Otherwise it is followed by the next
499 * @i2c_msg transaction segment, beginning with a (repeated) START.
500 *
501 * Alternatively, when the adapter supports I2C_FUNC_PROTOCOL_MANGLING then
502 * passing certain @flags may have changed those standard protocol behaviors.
503 * Those flags are only for use with broken/nonconforming slaves, and with
504 * adapters which are known to support the specific mangling options they
505 * need (one or more of IGNORE_NAK, NO_RD_ACK, NOSTART, and REV_DIR_ADDR).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 */
507struct i2c_msg {
508 __u16 addr; /* slave address */
David Brownell438d6c22006-12-10 21:21:31 +0100509 __u16 flags;
David Brownella64ec072007-10-13 23:56:31 +0200510#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
511#define I2C_M_RD 0x0001 /* read data, from slave to master */
512#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
513#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
514#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
515#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
516#define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
David Brownell438d6c22006-12-10 21:21:31 +0100517 __u16 len; /* msg length */
518 __u8 *buf; /* pointer to msg data */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519};
520
521/* To determine what functionality is present */
522
523#define I2C_FUNC_I2C 0x00000001
524#define I2C_FUNC_10BIT_ADDR 0x00000002
Jean Delvare3ae70de2008-10-22 20:21:32 +0200525#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_NOSTART etc. */
David Brownell6662cbb2007-10-13 23:56:33 +0200526#define I2C_FUNC_SMBUS_PEC 0x00000008
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
David Brownell438d6c22006-12-10 21:21:31 +0100528#define I2C_FUNC_SMBUS_QUICK 0x00010000
529#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
530#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
531#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
532#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
533#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
534#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
535#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
536#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
537#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */
539#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540
Jean Delvare3ae70de2008-10-22 20:21:32 +0200541#define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
542 I2C_FUNC_SMBUS_WRITE_BYTE)
543#define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
544 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
545#define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
546 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
547#define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
548 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
549#define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
550 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551
Jean Delvare3ae70de2008-10-22 20:21:32 +0200552#define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
553 I2C_FUNC_SMBUS_BYTE | \
554 I2C_FUNC_SMBUS_BYTE_DATA | \
555 I2C_FUNC_SMBUS_WORD_DATA | \
556 I2C_FUNC_SMBUS_PROC_CALL | \
557 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
558 I2C_FUNC_SMBUS_I2C_BLOCK | \
559 I2C_FUNC_SMBUS_PEC)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560
David Brownell438d6c22006-12-10 21:21:31 +0100561/*
562 * Data for SMBus Messages
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 */
David Brownell438d6c22006-12-10 21:21:31 +0100564#define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565union i2c_smbus_data {
566 __u8 byte;
567 __u16 word;
Hideki Iwamoto332bf922005-09-25 16:56:43 +0200568 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200569 /* and one more for user-space compatibility */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570};
571
Jean Delvareae7193f2008-07-14 22:38:24 +0200572/* i2c_smbus_xfer read or write markers */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573#define I2C_SMBUS_READ 1
574#define I2C_SMBUS_WRITE 0
575
David Brownell438d6c22006-12-10 21:21:31 +0100576/* SMBus transaction types (size parameter in the above functions)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
578#define I2C_SMBUS_QUICK 0
579#define I2C_SMBUS_BYTE 1
David Brownell438d6c22006-12-10 21:21:31 +0100580#define I2C_SMBUS_BYTE_DATA 2
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581#define I2C_SMBUS_WORD_DATA 3
582#define I2C_SMBUS_PROC_CALL 4
583#define I2C_SMBUS_BLOCK_DATA 5
Jean Delvare4b2643d2007-07-12 14:12:29 +0200584#define I2C_SMBUS_I2C_BLOCK_BROKEN 6
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585#define I2C_SMBUS_BLOCK_PROC_CALL 7 /* SMBus 2.0 */
Jean Delvare4b2643d2007-07-12 14:12:29 +0200586#define I2C_SMBUS_I2C_BLOCK_DATA 8
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588#endif /* _LINUX_I2C_H */