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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
Jean Delvare5694f8a2012-03-26 21:47:19 +020020 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
21 MA 02110-1301 USA. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070022/* ------------------------------------------------------------------------- */
23
David Woodhousea1b92982006-04-25 14:14:52 +010024/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 Frodo Looijaard <frodol@dds.nl> */
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#ifndef _LINUX_I2C_H
27#define _LINUX_I2C_H
28
Greg Kroah-Hartmana9d1b242005-10-22 00:23:27 +020029#include <linux/mod_devicetable.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/device.h> /* for struct device */
Tim Schmielau4e57b682005-10-30 15:03:48 -080031#include <linux/sched.h> /* for completion */
Ingo Molnar5c085d32006-01-18 23:16:04 +010032#include <linux/mutex.h>
Grant Likelyd12d42f2010-04-13 16:12:28 -070033#include <linux/of.h> /* for struct device_node */
Jonathan Cameron06a67842011-10-30 13:47:25 +010034#include <linux/swab.h> /* for swab16 */
David Howells607ca462012-10-13 10:46:48 +010035#include <uapi/linux/i2c.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
Jon Smirle9ca9eb2008-07-14 22:38:35 +020037extern struct bus_type i2c_bus_type;
Michael Lawnick08263742010-08-11 18:21:02 +020038extern struct device_type i2c_adapter_type;
Jon Smirle9ca9eb2008-07-14 22:38:35 +020039
Linus Torvalds1da177e2005-04-16 15:20:36 -070040/* --- General options ------------------------------------------------ */
41
42struct i2c_msg;
43struct i2c_algorithm;
44struct i2c_adapter;
45struct i2c_client;
46struct i2c_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -070047union i2c_smbus_data;
Jean Delvare4735c982008-07-14 22:38:36 +020048struct i2c_board_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Paul Gortmakerde477252011-05-26 13:46:22 -040050struct module;
51
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 Delvare0cc43a12011-01-10 22:11:23 +010060extern int i2c_master_send(const struct i2c_client *client, const char *buf,
Jean Delvare3ae70de2008-10-22 20:21:32 +020061 int count);
Jean Delvare0cc43a12011-01-10 22:11:23 +010062extern int i2c_master_recv(const struct i2c_client *client, char *buf,
63 int count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65/* Transfer num messages.
66 */
Jean Delvare3ae70de2008-10-22 20:21:32 +020067extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
68 int num);
Jean Delvareb37d2a32012-06-29 07:47:19 -030069/* Unlocked flavor */
70extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
71 int num);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
73/* This is the very generalized SMBus access routine. You probably do not
74 want to use this, though; one of the functions below may be much easier,
David Brownell438d6c22006-12-10 21:21:31 +010075 and probably just as fast.
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 Note that we use i2c_adapter here, because you do not need a specific
77 smbus adapter to call this function. */
Jean Delvare3ae70de2008-10-22 20:21:32 +020078extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
79 unsigned short flags, char read_write, u8 command,
80 int size, union i2c_smbus_data *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
82/* Now follow the 'nice' access routines. These also document the calling
Jean Delvareae7193f2008-07-14 22:38:24 +020083 conventions of i2c_smbus_xfer. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
Jean Delvare0cc43a12011-01-10 22:11:23 +010085extern s32 i2c_smbus_read_byte(const struct i2c_client *client);
86extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
87extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client,
88 u8 command);
89extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client,
Jean Delvare3ae70de2008-10-22 20:21:32 +020090 u8 command, u8 value);
Jean Delvare0cc43a12011-01-10 22:11:23 +010091extern s32 i2c_smbus_read_word_data(const struct i2c_client *client,
92 u8 command);
93extern s32 i2c_smbus_write_word_data(const struct i2c_client *client,
Jean Delvare3ae70de2008-10-22 20:21:32 +020094 u8 command, u16 value);
Jonathan Cameron06a67842011-10-30 13:47:25 +010095
96static inline s32
97i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command)
98{
99 s32 value = i2c_smbus_read_word_data(client, command);
100
101 return (value < 0) ? value : swab16(value);
102}
103
104static inline s32
105i2c_smbus_write_word_swapped(const struct i2c_client *client,
106 u8 command, u16 value)
107{
108 return i2c_smbus_write_word_data(client, command, swab16(value));
109}
110
Jean Delvareb86a1bc2007-05-01 23:26:34 +0200111/* Returns the number of read bytes */
Jean Delvare0cc43a12011-01-10 22:11:23 +0100112extern s32 i2c_smbus_read_block_data(const struct i2c_client *client,
Jean Delvareb86a1bc2007-05-01 23:26:34 +0200113 u8 command, u8 *values);
Jean Delvare0cc43a12011-01-10 22:11:23 +0100114extern s32 i2c_smbus_write_block_data(const struct i2c_client *client,
Jean Delvare3ae70de2008-10-22 20:21:32 +0200115 u8 command, u8 length, const u8 *values);
Jean Delvare31ec5bc2005-10-08 00:04:13 +0200116/* Returns the number of read bytes */
Jean Delvare0cc43a12011-01-10 22:11:23 +0100117extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client,
Jean Delvare4b2643d2007-07-12 14:12:29 +0200118 u8 command, u8 length, u8 *values);
Jean Delvare0cc43a12011-01-10 22:11:23 +0100119extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client,
Jean Delvare21bbd692006-01-09 15:19:18 +1100120 u8 command, u8 length,
Krzysztof Halasa46f5ed72006-06-12 21:42:20 +0200121 const u8 *values);
Jean Delvare23af8402009-06-19 16:58:20 +0200122#endif /* I2C */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123
Jean Delvare4735c982008-07-14 22:38:36 +0200124/**
125 * struct i2c_driver - represent an I2C device driver
126 * @class: What kind of i2c device we instantiate (for detect)
Jean Delvarefe6fc252011-03-20 14:50:53 +0100127 * @attach_adapter: Callback for bus addition (deprecated)
Jean Delvare729d6dd2009-06-19 16:58:18 +0200128 * @probe: Callback for device binding
129 * @remove: Callback for device unbinding
Jean Delvare96e21e42008-08-28 08:33:23 +0200130 * @shutdown: Callback for device shutdown
131 * @suspend: Callback for device suspend
132 * @resume: Callback for device resume
Randy Dunlap72d2e9f2010-08-09 16:37:16 -0700133 * @alert: Alert callback, for example for the SMBus alert protocol
Jean Delvare96e21e42008-08-28 08:33:23 +0200134 * @command: Callback for bus-wide signaling (optional)
135 * @driver: Device driver model driver
136 * @id_table: List of I2C devices supported by this driver
Jean Delvare4735c982008-07-14 22:38:36 +0200137 * @detect: Callback for device detection
Jean Delvarec3813d62009-12-14 21:17:25 +0100138 * @address_list: The I2C addresses to probe (for detect)
Jean Delvare4735c982008-07-14 22:38:36 +0200139 * @clients: List of detected clients we created (for i2c-core use only)
Laurent Riffard35d8b2e2005-11-26 20:34:05 +0100140 *
141 * The driver.owner field should be set to the module owner of this driver.
142 * The driver.name field should be set to the name of this driver.
Jean Delvare4735c982008-07-14 22:38:36 +0200143 *
Vivien Didelot0ec13862012-10-05 22:23:54 +0200144 * For automatic device detection, both @detect and @address_list must
Jean Delvare4735c982008-07-14 22:38:36 +0200145 * be defined. @class should also be set, otherwise only devices forced
146 * with module parameters will be created. The detect function must
147 * fill at least the name field of the i2c_board_info structure it is
148 * handed upon successful detection, and possibly also the flags field.
149 *
150 * If @detect is missing, the driver will still work fine for enumerated
151 * devices. Detected devices simply won't be supported. This is expected
152 * for the many I2C/SMBus devices which can't be detected reliably, and
153 * the ones which can always be enumerated in practice.
154 *
155 * The i2c_client structure which is handed to the @detect callback is
156 * not a real i2c_client. It is initialized just enough so that you can
157 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
158 * else with it. In particular, calling dev_dbg and friends on it is
159 * not allowed.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161struct i2c_driver {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 unsigned int class;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
Lars-Peter Clausen19baba42013-03-09 08:16:44 +0000164 /* Notifies the driver that a new bus has appeared. You should avoid
165 * using this, it will be removed in a near future.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 */
Jean Delvarefe6fc252011-03-20 14:50:53 +0100167 int (*attach_adapter)(struct i2c_adapter *) __deprecated;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168
Jean Delvare729d6dd2009-06-19 16:58:18 +0200169 /* Standard driver model interfaces */
Jean Delvared2653e92008-04-29 23:11:39 +0200170 int (*probe)(struct i2c_client *, const struct i2c_device_id *);
David Brownella1d9e6e2007-05-01 23:26:30 +0200171 int (*remove)(struct i2c_client *);
David Brownell7b4fbc52007-05-01 23:26:30 +0200172
David Brownellf37dd802007-02-13 22:09:00 +0100173 /* driver model interfaces that don't relate to enumeration */
174 void (*shutdown)(struct i2c_client *);
175 int (*suspend)(struct i2c_client *, pm_message_t mesg);
176 int (*resume)(struct i2c_client *);
177
Jean Delvareb5527a72010-03-02 12:23:42 +0100178 /* Alert callback, for example for the SMBus alert protocol.
179 * The format and meaning of the data value depends on the protocol.
180 * For the SMBus alert protocol, there is a single bit of data passed
181 * as the alert response's low bit ("event flag").
182 */
183 void (*alert)(struct i2c_client *, unsigned int data);
184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 /* a ioctl like command that can be used to perform specific functions
186 * with the device.
187 */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200188 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189
190 struct device_driver driver;
Jean Delvared2653e92008-04-29 23:11:39 +0200191 const struct i2c_device_id *id_table;
Jean Delvare4735c982008-07-14 22:38:36 +0200192
193 /* Device detection callback for automatic device creation */
Jean Delvare310ec792009-12-14 21:17:23 +0100194 int (*detect)(struct i2c_client *, struct i2c_board_info *);
Jean Delvarec3813d62009-12-14 21:17:25 +0100195 const unsigned short *address_list;
Jean Delvare4735c982008-07-14 22:38:36 +0200196 struct list_head clients;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197};
198#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
199
David Brownell2096b952007-05-01 23:26:28 +0200200/**
201 * struct i2c_client - represent an I2C slave device
David Brownelld64f73b2007-07-12 14:12:28 +0200202 * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address;
203 * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking
David Brownell2096b952007-05-01 23:26:28 +0200204 * @addr: Address used on the I2C bus connected to the parent adapter.
205 * @name: Indicates the type of the device, usually a chip name that's
206 * generic enough to hide second-sourcing and compatible revisions.
David Brownelld64f73b2007-07-12 14:12:28 +0200207 * @adapter: manages the bus segment hosting this I2C device
Randy Dunlapaa3481d2007-07-31 00:39:02 -0700208 * @driver: device's driver, hence pointer to access routines
David Brownell2096b952007-05-01 23:26:28 +0200209 * @dev: Driver model device node for the slave.
David Brownelld64f73b2007-07-12 14:12:28 +0200210 * @irq: indicates the IRQ generated by this device (if any)
Jean Delvare99cd8e22009-06-19 16:58:20 +0200211 * @detected: member of an i2c_driver.clients list or i2c-core's
212 * userspace_devices list
David Brownell2096b952007-05-01 23:26:28 +0200213 *
214 * An i2c_client identifies a single device (i.e. chip) connected to an
David Brownelld64f73b2007-07-12 14:12:28 +0200215 * i2c bus. The behaviour exposed to Linux is defined by the driver
216 * managing the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 */
218struct i2c_client {
David Brownell2096b952007-05-01 23:26:28 +0200219 unsigned short flags; /* div., see below */
David Brownell438d6c22006-12-10 21:21:31 +0100220 unsigned short addr; /* chip address - NOTE: 7bit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 /* addresses are stored in the */
Jean Delvare50718602005-07-20 00:02:32 +0200222 /* _LOWER_ 7 bits */
David Brownell2096b952007-05-01 23:26:28 +0200223 char name[I2C_NAME_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 struct i2c_adapter *adapter; /* the adapter we sit on */
225 struct i2c_driver *driver; /* and our access routines */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 struct device dev; /* the device structure */
Wolfram Sang8e29da92008-07-01 22:38:18 +0200227 int irq; /* irq issued by device */
Jean Delvare4735c982008-07-14 22:38:36 +0200228 struct list_head detected;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229};
230#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
231
David Brownell9b766b82008-01-27 18:14:51 +0100232extern struct i2c_client *i2c_verify_client(struct device *dev);
Stephen Warren643dd092012-04-17 12:43:33 -0600233extern struct i2c_adapter *i2c_verify_adapter(struct device *dev);
David Brownell9b766b82008-01-27 18:14:51 +0100234
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500235static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
236{
Mark M. Hoffmand75d53c2007-07-12 14:12:28 +0200237 struct device * const dev = container_of(kobj, struct device, kobj);
238 return to_i2c_client(dev);
bgardner@wabtec.coma61fc682005-07-27 12:43:03 -0500239}
240
Jean Delvare7d1d8992008-10-22 20:21:31 +0200241static inline void *i2c_get_clientdata(const struct i2c_client *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200243 return dev_get_drvdata(&dev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244}
245
Jean Delvare3ae70de2008-10-22 20:21:32 +0200246static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200248 dev_set_drvdata(&dev->dev, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249}
250
David Brownell9c1600e2007-05-01 23:26:31 +0200251/**
252 * struct i2c_board_info - template for device creation
Jean Delvareeb8a7902008-05-18 20:49:41 +0200253 * @type: chip type, to initialize i2c_client.name
David Brownell9c1600e2007-05-01 23:26:31 +0200254 * @flags: to initialize i2c_client.flags
255 * @addr: stored in i2c_client.addr
256 * @platform_data: stored in i2c_client.dev.platform_data
Anton Vorontsov11f1f2a2008-10-22 20:21:33 +0200257 * @archdata: copied into i2c_client.dev.archdata
Randy Dunlap72d2e9f2010-08-09 16:37:16 -0700258 * @of_node: pointer to OpenFirmware device node
Mika Westerberg907ddf82012-11-23 12:23:40 +0100259 * @acpi_node: ACPI device node
David Brownell9c1600e2007-05-01 23:26:31 +0200260 * @irq: stored in i2c_client.irq
David Brownelld64f73b2007-07-12 14:12:28 +0200261 *
David Brownell9c1600e2007-05-01 23:26:31 +0200262 * I2C doesn't actually support hardware probing, although controllers and
263 * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's
264 * a device at a given address. Drivers commonly need more information than
265 * that, such as chip type, configuration, associated IRQ, and so on.
266 *
267 * i2c_board_info is used to build tables of information listing I2C devices
Jean Delvare729d6dd2009-06-19 16:58:18 +0200268 * that are present. This information is used to grow the driver model tree.
269 * For mainboards this is done statically using i2c_register_board_info();
270 * bus numbers identify adapters that aren't yet available. For add-on boards,
271 * i2c_new_device() does this dynamically with the adapter already known.
David Brownell9c1600e2007-05-01 23:26:31 +0200272 */
273struct i2c_board_info {
David Brownell9c1600e2007-05-01 23:26:31 +0200274 char type[I2C_NAME_SIZE];
275 unsigned short flags;
276 unsigned short addr;
277 void *platform_data;
Anton Vorontsov11f1f2a2008-10-22 20:21:33 +0200278 struct dev_archdata *archdata;
Grant Likelyd12d42f2010-04-13 16:12:28 -0700279 struct device_node *of_node;
Mika Westerberg907ddf82012-11-23 12:23:40 +0100280 struct acpi_dev_node acpi_node;
David Brownell9c1600e2007-05-01 23:26:31 +0200281 int irq;
282};
283
284/**
Jean Delvare3760f732008-04-29 23:11:40 +0200285 * I2C_BOARD_INFO - macro used to list an i2c device and its address
286 * @dev_type: identifies the device type
David Brownell9c1600e2007-05-01 23:26:31 +0200287 * @dev_addr: the device's address on the bus.
288 *
289 * This macro initializes essential fields of a struct i2c_board_info,
290 * declaring what has been provided on a particular board. Optional
Jean Delvare3760f732008-04-29 23:11:40 +0200291 * fields (such as associated irq, or device-specific platform_data)
292 * are provided using conventional syntax.
David Brownell9c1600e2007-05-01 23:26:31 +0200293 */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200294#define I2C_BOARD_INFO(dev_type, dev_addr) \
Ben Hutchingsc758e8c2009-04-13 17:02:14 +0200295 .type = dev_type, .addr = (dev_addr)
David Brownell9c1600e2007-05-01 23:26:31 +0200296
297
Jean Delvare23af8402009-06-19 16:58:20 +0200298#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
David Brownell9c1600e2007-05-01 23:26:31 +0200299/* Add-on boards should register/unregister their devices; e.g. a board
300 * with integrated I2C, a config eeprom, sensors, and a codec that's
301 * used in conjunction with the primary hardware.
302 */
303extern struct i2c_client *
304i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
305
Jean Delvare12b5053a2007-05-01 23:26:31 +0200306/* If you don't know the exact address of an I2C device, use this variant
307 * instead, which can probe for device presence in a list of possible
Jean Delvare9a942412010-08-11 18:20:56 +0200308 * addresses. The "probe" callback function is optional. If it is provided,
309 * it must return 1 on successful probe, 0 otherwise. If it is not provided,
310 * a default probing method is used.
Jean Delvare12b5053a2007-05-01 23:26:31 +0200311 */
312extern struct i2c_client *
313i2c_new_probed_device(struct i2c_adapter *adap,
314 struct i2c_board_info *info,
Jean Delvare9a942412010-08-11 18:20:56 +0200315 unsigned short const *addr_list,
316 int (*probe)(struct i2c_adapter *, unsigned short addr));
Jean Delvare12b5053a2007-05-01 23:26:31 +0200317
Jean Delvared44f19d2010-08-11 18:20:57 +0200318/* Common custom probe functions */
319extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
320
David Brownelle9f13732008-01-27 18:14:52 +0100321/* For devices that use several addresses, use i2c_new_dummy() to make
322 * client handles for the extra addresses.
323 */
324extern struct i2c_client *
Jean Delvare60b129d2008-05-11 20:37:06 +0200325i2c_new_dummy(struct i2c_adapter *adap, u16 address);
David Brownelle9f13732008-01-27 18:14:52 +0100326
David Brownell9c1600e2007-05-01 23:26:31 +0200327extern void i2c_unregister_device(struct i2c_client *);
Jean Delvare23af8402009-06-19 16:58:20 +0200328#endif /* I2C */
David Brownell9c1600e2007-05-01 23:26:31 +0200329
330/* Mainboard arch_initcall() code should register all its I2C devices.
331 * This is done at arch_initcall time, before declaring any i2c adapters.
332 * Modules for add-on boards must use other calls.
333 */
David Brownell26386762008-02-24 20:03:42 +0100334#ifdef CONFIG_I2C_BOARDINFO
David Brownell9c1600e2007-05-01 23:26:31 +0200335extern int
Jean Delvare3ae70de2008-10-22 20:21:32 +0200336i2c_register_board_info(int busnum, struct i2c_board_info const *info,
337 unsigned n);
David Brownell26386762008-02-24 20:03:42 +0100338#else
339static inline int
Jean Delvare3ae70de2008-10-22 20:21:32 +0200340i2c_register_board_info(int busnum, struct i2c_board_info const *info,
341 unsigned n)
David Brownell26386762008-02-24 20:03:42 +0100342{
343 return 0;
344}
Jean Delvare23af8402009-06-19 16:58:20 +0200345#endif /* I2C_BOARDINFO */
David Brownell9c1600e2007-05-01 23:26:31 +0200346
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347/*
348 * The following structs are for those who like to implement new bus drivers:
349 * i2c_algorithm is the interface to a class of hardware solutions which can
350 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
351 * to name two of the most common.
352 */
353struct i2c_algorithm {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 /* If an adapter algorithm can't do I2C-level access, set master_xfer
David Brownell438d6c22006-12-10 21:21:31 +0100355 to NULL. If an adapter algorithm can do SMBus access, set
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 smbus_xfer. If set to NULL, the SMBus protocol is simulated
357 using common I2C messages */
Jean Delvare8ced8ee2006-07-01 17:12:53 +0200358 /* master_xfer should return the number of messages successfully
359 processed, or a negative value on error */
Jean Delvare3ae70de2008-10-22 20:21:32 +0200360 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs,
361 int num);
David Brownell438d6c22006-12-10 21:21:31 +0100362 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
Jean Delvare3ae70de2008-10-22 20:21:32 +0200363 unsigned short flags, char read_write,
364 u8 command, int size, union i2c_smbus_data *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 /* To determine what the adapter supports */
367 u32 (*functionality) (struct i2c_adapter *);
368};
369
Viresh Kumar5f9296b2012-02-28 18:26:31 +0530370/**
371 * struct i2c_bus_recovery_info - I2C bus recovery information
372 * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or
373 * i2c_generic_scl_recovery() or i2c_generic_gpio_recovery().
374 * @get_scl: This gets current value of SCL line. Mandatory for generic SCL
375 * recovery. Used internally for generic GPIO recovery.
376 * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used
377 * internally for generic GPIO recovery.
378 * @get_sda: This gets current value of SDA line. Optional for generic SCL
379 * recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO
380 * recovery.
381 * @prepare_recovery: This will be called before starting recovery. Platform may
382 * configure padmux here for SDA/SCL line or something else they want.
383 * @unprepare_recovery: This will be called after completing recovery. Platform
384 * may configure padmux here for SDA/SCL line or something else they want.
385 * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery.
386 * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery.
387 */
388struct i2c_bus_recovery_info {
389 int (*recover_bus)(struct i2c_adapter *);
390
391 int (*get_scl)(struct i2c_adapter *);
392 void (*set_scl)(struct i2c_adapter *, int val);
393 int (*get_sda)(struct i2c_adapter *);
394
395 void (*prepare_recovery)(struct i2c_bus_recovery_info *bri);
396 void (*unprepare_recovery)(struct i2c_bus_recovery_info *bri);
397
398 /* gpio recovery */
399 int scl_gpio;
400 int sda_gpio;
401};
402
403int i2c_recover_bus(struct i2c_adapter *adap);
404
405/* Generic recovery routines */
406int i2c_generic_gpio_recovery(struct i2c_adapter *adap);
407int i2c_generic_scl_recovery(struct i2c_adapter *adap);
408
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409/*
410 * i2c_adapter is the structure used to identify a physical i2c bus along
411 * with the access algorithms necessary to access it.
412 */
413struct i2c_adapter {
414 struct module *owner;
Wolfram Sang14f55f72008-10-22 20:21:30 +0200415 unsigned int class; /* classes to allow probing for */
David Brownellaf71ff62006-09-03 22:37:11 +0200416 const struct i2c_algorithm *algo; /* the algorithm to access the bus */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417 void *algo_data;
418
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 /* data fields that are valid for all devices */
Mika Kuoppala194684e2009-12-06 17:06:22 +0100420 struct rt_mutex bus_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
Jean Delvarecd97f392009-02-24 19:19:49 +0100422 int timeout; /* in jiffies */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 int retries;
424 struct device dev; /* the adapter device */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 int nr;
David Brownell2096b952007-05-01 23:26:28 +0200427 char name[48];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 struct completion dev_released;
Jean Delvare6629dcf2010-05-04 11:09:28 +0200429
Jean Delvaredafc50d2010-08-11 18:21:01 +0200430 struct mutex userspace_clients_lock;
Jean Delvare6629dcf2010-05-04 11:09:28 +0200431 struct list_head userspace_clients;
Viresh Kumar5f9296b2012-02-28 18:26:31 +0530432
433 struct i2c_bus_recovery_info *bus_recovery_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434};
David Brownellef2c83212007-05-01 23:26:28 +0200435#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
Jean Delvare7d1d8992008-10-22 20:21:31 +0200437static inline void *i2c_get_adapdata(const struct i2c_adapter *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200439 return dev_get_drvdata(&dev->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440}
441
Jean Delvare3ae70de2008-10-22 20:21:32 +0200442static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443{
Jean Delvare3ae70de2008-10-22 20:21:32 +0200444 dev_set_drvdata(&dev->dev, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445}
446
Jean Delvare97cc4d42010-10-24 18:16:57 +0200447static inline struct i2c_adapter *
448i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
Michael Lawnick08263742010-08-11 18:21:02 +0200449{
Jean Delvare97cc4d42010-10-24 18:16:57 +0200450 struct device *parent = adapter->dev.parent;
451
452 if (parent != NULL && parent->type == &i2c_adapter_type)
453 return to_i2c_adapter(parent);
454 else
455 return NULL;
Michael Lawnick08263742010-08-11 18:21:02 +0200456}
457
Jean Delvare7ae31482011-03-20 14:50:52 +0100458int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
459
Jean Delvarefe61e072010-08-11 18:20:58 +0200460/* Adapter locking functions, exported for shared pin cases */
461void i2c_lock_adapter(struct i2c_adapter *);
462void i2c_unlock_adapter(struct i2c_adapter *);
Jean Delvareafa08972009-11-07 13:10:46 +0100463
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464/*flags for the client struct: */
David Brownell3bbb8352007-10-13 23:56:29 +0200465#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
466#define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */
467 /* Must equal I2C_M_TEN below */
468#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
Laurent Pinchartd47726c2012-07-24 14:13:59 +0200469#define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */
470 /* Must match I2C_M_STOP|IGNORE_NAK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471
472/* i2c adapter classes (bitmask) */
473#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
Jean Delvarec1b6b4f2008-07-14 22:38:28 +0200474#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
Jean Delvare774466a2011-05-25 20:43:32 +0200475#define I2C_CLASS_SPD (1<<7) /* Memory modules */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477/* Internal numbers to terminate lists */
478#define I2C_CLIENT_END 0xfffeU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
Hans Verkuilc7036672009-06-19 16:58:21 +0200480/* Construct an I2C_CLIENT_END-terminated array of i2c addresses */
481#define I2C_ADDRS(addr, addrs...) \
482 ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
483
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
485/* ----- functions exported by i2c.o */
486
487/* administration...
488 */
Jean Delvare23af8402009-06-19 16:58:20 +0200489#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490extern int i2c_add_adapter(struct i2c_adapter *);
Lars-Peter Clausen71546302013-03-09 08:16:47 +0000491extern void i2c_del_adapter(struct i2c_adapter *);
David Brownell6e13e642007-05-01 23:26:31 +0200492extern int i2c_add_numbered_adapter(struct i2c_adapter *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800494extern int i2c_register_driver(struct module *, struct i2c_driver *);
Jean Delvareb3e82092007-05-01 23:26:32 +0200495extern void i2c_del_driver(struct i2c_driver *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496
Paul Gortmakereb5589a2011-05-27 09:02:11 -0400497/* use a define to avoid include chaining to get THIS_MODULE */
498#define i2c_add_driver(driver) \
499 i2c_register_driver(THIS_MODULE, driver)
Greg Kroah-Hartmande59cf92005-12-06 15:33:15 -0800500
Jean Delvaree48d3312008-01-27 18:14:48 +0100501extern struct i2c_client *i2c_use_client(struct i2c_client *client);
502extern void i2c_release_client(struct i2c_client *client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503
504/* call the i2c_client->command() of all attached clients with
505 * the given arguments */
506extern void i2c_clients_command(struct i2c_adapter *adap,
507 unsigned int cmd, void *arg);
508
Jean Delvared735b342011-03-20 14:50:52 +0100509extern struct i2c_adapter *i2c_get_adapter(int nr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510extern void i2c_put_adapter(struct i2c_adapter *adap);
511
512
513/* Return the functionality mask */
514static inline u32 i2c_get_functionality(struct i2c_adapter *adap)
515{
516 return adap->algo->functionality(adap);
517}
518
519/* Return 1 if adapter supports everything we need, 0 if not. */
520static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func)
521{
522 return (func & i2c_get_functionality(adap)) == func;
523}
524
Jean Delvare3ae70de2008-10-22 20:21:32 +0200525/* Return the adapter number for a specific adapter */
Jean Delvarecdcb1922005-07-28 23:09:40 +0200526static inline int i2c_adapter_id(struct i2c_adapter *adap)
527{
528 return adap->nr;
529}
Lars-Peter Clausen7c927842011-11-16 10:13:36 +0100530
531/**
532 * module_i2c_driver() - Helper macro for registering a I2C driver
533 * @__i2c_driver: i2c_driver struct
534 *
535 * Helper macro for I2C drivers which do not do anything special in module
536 * init/exit. This eliminates a lot of boilerplate. Each module may only
537 * use this macro once, and calling it replaces module_init() and module_exit()
538 */
539#define module_i2c_driver(__i2c_driver) \
540 module_driver(__i2c_driver, i2c_add_driver, \
541 i2c_del_driver)
542
Jean Delvare23af8402009-06-19 16:58:20 +0200543#endif /* I2C */
Mika Westerberg907ddf82012-11-23 12:23:40 +0100544
545#if IS_ENABLED(CONFIG_ACPI_I2C)
546extern void acpi_i2c_register_devices(struct i2c_adapter *adap);
547#else
548static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {}
549#endif
550
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551#endif /* _LINUX_I2C_H */